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Faculty Biographies
William Y. Arms
Professor
wya@cs.cornell.edu
D.Phil. University of Sussex U.K., 1973
My research interests concentrate on web information
systems, digital libraries and electronic publishing. These fields integrate
methods from many disciplines, so that the work ranges from technical
topics, such as distributed computing and information representation,
to the economic and social aspects of change. My book Digital Libraries
was published by the MIT Press in winter 2000. This year we received a
major grant to integrate many separate projects into the NSF's new digital
library for science, mathematics, engineering and technology education.
This is likely to be the largest and most heterogeneous digital library
yet attempted. Cornell's multidisciplinary team combines computer science,
librarian and user interfaces design expertise. One of my principal interests
is the change in scientific publication as online materials replace printed
journals as the primary means of creating, storing, and distributing research
information. I have recently completed a period as chair of the ACM Publications
Board, am a member of the MIT Press Management Board, and am a member
of a strategic planning committee of the American Physical Society. As
part of the NSF-funded Prism project, I am working with the Library of
Congress to develop methods for long-term preservation of materials on
the Web.
University Activities
Chair, Provost's Advisory Committee on Distance Education. Director, eCornell.
Member of the Faculty Senate, the Faculty Advisory Board on Information
Technology, and the University Library Board.
Professional Activities
Publications Board, Association for Computing Machinery.
National Research Council study Issues for Science and Engineering Researchers
in the Digital Age.
MIT Press, member of the Management Board and editor of the series on
Digital Libraries and Electronic Publishing.
Lectures
The Impact of the Internet on Research Universities. National Science
Foundation (April 13, 2001).
The National Science Digital Library Program. Coalition for Networked
Information (April 9, 2001).
Quality Control in Scholarly Publishing. What are the Alternatives to
Peer Review? Keynote, workshop on the
Open Archives initiative and peer review
journals in Europe, Geneva (March 22 - 24, 2001).
Minerva: The Web Preservation Project. Library of Congress (February 2,
2001).
Strategies for Collecting and Preserving Open Access Materials on the
Web. Federal Library and Information
Center Committee, Washington D.C. (December
7, 2000).
The Web as an Open Access Digital Library. Closing address, 2000 Kyoto
International Conference on Digital
Libraries: Research and Practice, Kyoto,
Japan (November 15, 2000).
Open Access to Digital Libraries. Must Research Libraries be Expensive?
Keynote address, European
Conference on Digital Libraries, ECDL2000,
Lisbon, Portugal (September 18, 2000).
Publications
"Uniform Resource Names: Handles, PURLs, and Digital Object Identifiers."
Communication of the ACM,
44(5):68 (May, 2001).
"Collecting and Preserving the Web: The Minerva Prototype."
RLG DigiNews 5(2) (April2001). With Roger
Adkins, Cassy Ammen, and Allene Hayes.
(http://www.rlg.org/preserv/diginews/diginews5-2.html#feature1)
"An Architecture for Reference Linking." Technical Report TR
2000-1820,Computer Science Department,
Cornell University (October, 2000). With
Donna Bergmark, and Carl Lagoze.
"Automated Digital Libraries. How Effectively can Computers be used
for the Skilled Tasks of Professional
Librarianship?" D-Lib Magazine
6(7/8)(July/August, 2000).
(http://www.dlib.org/dlib/july00/arms/07arms.html
)
"Economic Models for Open-access Publishing." IMP(March,2000).(http://www.cisp.org/imp/march_2000
/03_00arms.htm). Digital Libraries. MIT Press, ISBN 0-262-01180-8,
2000.
Graeme Bailey
Professor
bailey@cs.cornell.edu
Ph.D. University of Birmingham U.K., 1977
Originally working in low-dimensional topology and
combinatorial group theory, through an odd mixture of circumstances I
have become actively involved in research in mathematics and medicine.
One of two ongoing research projects in this area is the modeling of lung
inflation, together with a research group at the Class One Trauma Center
at Upstate Medical Univ., Syracuse, NY. This is in the early stages of
a program to extend to various pathologies affecting elasticity and aimed
towards effective clinical treatments. The group, now having made some
significant advances in answering questions that had remained unsolved
for over 30 years, is now in the process of trying to obtain reliable
mathematical models. This involves building computer simulations of dynamic
packing results under constrained perturbations and deformations. The
other project is in understanding deformations of trans membrane proteins
used in cell-signaling processes. This is a carefully constrained version
of the protein-folding problems that have been exciting the mathematical
biology community in recent years; the application of a topological viewpoint
in collaborating with molecular pharmacologists and structural biologists
has already yielded some intriguing insights.
Honors/Awards
Kenneth A. Goldman '71 Excellence in Teaching Award, 2000.
University Activities
Adjunct Professor; Mathematics.
Member, Fellowship Selection Committees: Rhodes, Marshall, Churchill,
and Fulbright.
Member, WCHI-Development and Transition Committee.
Member, Donlon Fellows Development.
Member, Master of Engineering Committee.
Member, Cornell
EMS.
Faculty Advisor, Judo Club.
Kenneth P. Birman
Professor
ken@cs.cornell.edu
http://www.cs.cornell.edu/ken/
Ph.D. University of California, Berkeley, 1981
My research is concerned with reliability and security
in modern networked environments. This work has three broad themes. Our
main focus is on a new system called "Spinglass" (http://www.cs.cornell.edu/Info/Projects/Spinglass
). The idea is to explore a class of reliable multicast protocols that
are extremely scalable and provide unusually stable throughput under stress.
We believe that stable throughput is a common requirement in demanding
critical settings, but few reliable protocols have this property. By scalability,
we mean that a system which works with ten computers should also be usable
with ten thousand of them. Spinglass involves two subprojects. One, called
Astrolabe, is concerned with a new way to represent data in a network.
Astrolabe is like a network-wide database in which each computer or component
contributes a live tuple. As data change, Astrolabe propagates the updates.
The system uses a form of dynamically materialized view to continuously
compute summaries of th epicture of the network as a whole. This results
in a powerful new tool for distributed monitoring, management, control,
and live collaboration. Robbert van Renesse is the leader on this work,
and we're collaborating with Al Demers and Johannes Gehrke on aspects
related to databases and data mining. The second big part of Spinglass
is concerned with reliable multicast. We've developed a scalable multicast
protocol that gives probabilistic consistency guarantees, and we are finding
ways to apply this in practical settings. Graduate students looking at
these questions include Indranil Gupta, who is developing algorithms that
make direct use of probabilistic guarantees; Rimon Barr, who is looking
at adapting these tools for mobile networks; and Ranveer Chandra and Venugopalen
Ramasubramanian, who areinvestigating ad-hoc mobile networking. Kate Jenkins
and Ken Hopkinson are looking at applications that arise when using these
protocols in real-world settings arising from the restructuring of the
electric power grid.
Our third big activity is joint work with
Bob Constable's Nuprl project, and involves the use of formal methods
to prove properties of reliable communication protocols, such as those
used in Isis, Horus, and Ensemble.
Our project is funded primarily by DARPA, with some additional funding
from the Electric Power Research Institute and Microsoft Research. The
project is directed by myself, R. van Renesse, and W. Vogels. R. Bhoedjang
is visiting as a post-doc for a few years, and developing Intrusion Detection
software to make use of Astrolabe.
Honors
Stephen '57 and Marilyn Miles Excellence in Teaching Award, 2000.
University Activities
Committees: Founding Committee for Faculty of Computing and Information
Science; University Conflicts of Interest; Chairman of the Responsible
Conduct of Research Committee, Engineering College Policy Committee; IP
Advisory Council for the Cornell Research Foundation.
Lectures
Next Generation Internet: Unsafe at any Speed?
-. Keynote Speaker: ISDCS '01 (April, 2001).
-. University of Rochester (November, 2000).
-. IBM T.J. Watson Research Center (March, 2000).
-. Keynote: Middleware 2000.
Publications
"Technology Requirements for Virtual Overlay Networks." IEEE
Systems, Man and Cybernetics: Special issue
on Information Assurance (March, 2001).
"Next Generation Internet: Unsafe at Any Speed?" IEEE Computer,
Special issue on Infrastructure Protection
(Fall, 2000).
"Technology Challenges for Virtual Overlay Networks." IEEE
Systems, Man, and Cybernetics Information
Assurance and Security Workshop,
West Point, New York (June 6-7, 2000).
"Optimized Group Rekey for Group Communications Systems." Networked
and Distributed Systems Security
2000, San Diego, California. (V). Extended
version available as Cornell University, Computer Science TR99-
1764. With Ohad Rodeh, and Danny Dolev.
"A Dynamic Light-weight Group Service." Journal of Parallel
and Distributed Computing 60:1449-1479 (2000).
With Luis Rodrigues, Katherine Guo, and Paulo
Verissimo.
"A Gossip Protocol for Subgroup Multicast." International
Workshop on Applied Reliable Group
Communication (WARGC 2001), Phoenix,
AZ (April, 2001). With Kate Jenkins.
"Providing Efficient, Robust Error Recovery through Randomization."
International Workshop on Applied
Reliable Group Communication (WARGC 2001), Phoenix,
AZ (April, 2001). With Zhen Xiao.
"Anonymous Gossip: Improving Multicast Reliability in Ad-hoc Networks."
International Conference on
Distributed Computing systems (ICDCS 2001), Phoenix,
AZ (April, 2001). With Ranveer Chandra and Vanogupalen Ramasubramanian.
"A Randomized Error Recovery Algorithm for Reliable Multicast."
IEEE Infocom 2001 AK (April, 2001). With
Zhen Xiao.
"Using Epidemic Techniques for Building Ultra-scalable Reliable Communications
Systems." Workshop on
New Visions for Large-scale Networks: Research
and Applications, Vienna, VA (March, 2001). With
Werner Vogels, and Robbert van Renesse.
"Optimizing Buffer Management for Reliable Multicast." Submitted
to the 2nd Annual Workshop on Networked
Group Communication (NGC 2000), Palo Alto, CA
(November 8-10, 2000). With Zhen Xiao, and Robbert van
Renesse.
"Throughput Stability of Reliable Multicast Protocols." ADVIS'
2000, Dokuz Eylul University, Izmir, Turkey
(October 25-27, 2000). With Oznur Ozkasap.
"A Probabilistically Correct Election Protocol for Large Groups."
DISC 2000, Toledo, Spain (October 4-6,
2000). With Indranil Gupta, and Robbert van Renesse.
Publications-Landmark
"Bimodal Multicast." ACM Transactions on Computer Systems 17(2):41-88
(May, 1999). With M. Hayden, O.
Ozkasap, Z. Xiao, M. Budiu, and Y. Minsky.
"A Probabilistically Correct Leadership Election Protocol for Large
Groups." DISC-2000, Nov 2000, Toledo
Spain. With I. Gupta and R. van Renesse.
Martin Burtscher
Assistant
Professor
Member of the School of Electrical
and Computer Engineering and the Graduate Field of Computer Science
burtscher@csl.cornell.edu
http://www.csl.cornell.edu/~burtscher/
Ph.D. University of Colorado at Boulder, 2000
My
research interests are high-performance micro-processor architecture,
instruction-level parallelism, and compiler optimizations. In particular,
I am exploring hardware- and software-based value prediction, data compression,
and latency reduction techniques.
The constantly widening speed gap between CPUs
and memory is becoming more and more of a performance-limiting factor.
In fact, current high-end microprocessors already spend a substantial
amount of time waiting for memory accesses. To speed up program execution,
the CPU needs to process useful instructions while waiting for the memory.
One way of providing a processor with useful work is to predict what it
will have to do next. Many commodity microprocessors already contain branch
predictors to boost their performance, and it is likely that more predictors
will be needed to meet the continuing demand for ever-faster CPUs. Designing,
evaluating, and improving such predictors is an important focus of my
research.
Ongoing projects include locating novel domains that can benefit from
prediction, adding compiler support to aid and simplify the prediction
hardware, devising means to reduce predictor sizes and power consumption
without compromising performance, discovering as-of-yet unobserved patterns
to build new predictors, and using value- prediction techniques to enhance
branch-prediction accuracy and data-compression rates.
Lectures
Designing a High-performance Load-value Predictor. Hewlett-Packard Company
(December, 2000).
The Evolution of a High-performance Load-value Predictor. Lockheed Martin
Corporation (November, 2000).
The Design of a High-performance Load Value Predictor. Compaq Computer
Corporation (October, 2000).
Hybridizing and Coalescing Load-value Predictors. International Conference
on Computer Design (September,
2000).
Predictability and Exploitability of Load Values. Microsoft Research (June,
2000).
Publications
"Hybridizing and Coalescing Load-value Predictors." International
Conference on Computer Design, Austin, TX
(September, 2000) :81-92. With B. Zorn.
"Exploring Last n Value Prediction." International Conference
on Parallel Architectures and Compilation
Techniques, Paris, France (October, 1999):66-76.
With B. Zorn.
"Prediction Outcome History-based Confidence Estimation for Load-value
Prediction." Journal of Instruction-
level Parallelism1 (May 1999). http://www.jilp.org/vol1/
With B. Zorn.
Claire Cardie
Associate Professor
cardie@cs.cornell.edu
http://www.cs.cornell.edu/home/cardie/
Ph.D. University of Massachusetts
Amherst, 1994
My
primary research areas are Natural Language Processing (NLP) and Machine
Learning (ML) where we focus on developing corpus-based techniques for
understanding and extracting information from natural language texts.
In particular, my group investigates the use of machine learning techniques
as tools for guiding natural language system development and for exploring
the mechanisms that underlie language understanding. Our work encompasses
three related areas: (1) machine learning of natural language, (2) the
use of corpus-based NLP techniques to aid information retrieval (IR) and
summarization systems, and (3) the design of user-trainable NLP systems
that can efficiently and reliably extract the important information from
a document.
In the past year or so we have made progress on both the natural language
processing and machine learning aspects of our research. First, we have
extended our approach to partial parsing of natural language texts to
operate effectively in a weakly supervised learning framework. The original
approach, developed with graduate students Scott Mardis and David Pierce,
combines corpus-based grammar induction with a very simple pattern-matching
algorithm and an optional constituent verification step. In evaluations
on a number of large-scale partial parsing tasks involving on-line text,
the approach produces partial parsers that are both fast and accurate.
Unfortunately, however, large amounts of expensive,
human-annotated data are required for training. In new work with David
Pierce, we investigate the use of weakly supervised learning algorithms
for partial parsing that require only a small set of labeled training
instances. In particular, we examine the learning behavior of co-training,
a weakly supervised learning paradigm in which the redundancy of the learning
task is captured by training two classifiers using separate views of the
same data. This enables bootstrapping from a small set of labeled training
data via a large set of unlabeled data. For noun phrase bracketing, we
find that co-training reduces by 36 percent the difference in error between
co-trained classifiers and fully supervised classifiers trained on a labeled
version of all available data. However, degradation in the quality of
the bootstrapped data arises as an obstacle to further improvement. To
address this, we propose a moderately supervised variant of co-training
in which a human corrects the mistakes made during automatic labeling.
Our analysis suggests that corrected co-training and similar moderately
supervised methods may help co-training scale to other natural language
learning tasks that typically require large amounts of training data.
In a joint project with CoGenTex Inc. and the University of Montreal,
we have begun to extend existing corpus-based learning algorithms for
information extraction to acquire a broader set of extraction patterns.
We have implemented a new learning algorithm, Autoslog-XML, that can extract
linguistic entities beyond just noun phrases. Autoslog-XML is a semi-supervised
algorithm for locating useful extraction patterns from unrestricted text.
The learned extraction patterns have been employed to support domain-specific
multi-document summarization in the natural disasters domain. We have
also begun to investigate the application of the extraction pattern learning
algorithm for Korean texts. Graduate students Vincent Ng and Kiri Wagstaff
are part of this joint research effort.
The techniques described above can, in turn, be
used to support a number of practical, end-to-end text-processing tasks
in addition to multi-document summarization. For example, we are using
the corpus-based partial-parsing techniques as the primary linguistic
component in a new system for general-knowledge question answering. The
system combines techniques for standard information retrieval, query-dependent
text summarization, and shallow syntactic and semantic sentence analysis.
In a series of experiments, we examined the role of each statistical and
linguistic knowledge source in the question-answering system and find
that even very weak linguistic knowledge can offer substantial improvements
over purely IR-based techniques for question answering, especially when
smoothly integrated with statistical preferences computed by the IR subsystems.
Finally, in machine learning research with Kiri
Wagstaff, we are investigating the use of prior knowledge in the form
of user-supplied constraints to improve the performance of clustering
algorithms.
University Activities
College Scholar Advisor.
College Scholar Committee Chair.
Independent Major Advisor.
Cognitive Studies Concentration Advisor.
Member: Faculty of Computing and Information Founders; Faculty of Computing
and Information Working Group for Information Science; Faculty of Computing
and Information Working Group for Crosscutting Education Programs; Independent
Major Advisory Board; Provost's Advisory Group of Women in Science and
Engineering; Cognitive Studies Steering Committee; Computer Science Department
Ph.D. admissions committee; Department of Computer Science space committee;
Cognitive Studies Selection Committees for Summer Fellowships, for Continuing
Fellowships, and for Incoming Fellowships.
Professional Activities
Secretary: North American Association for Computational Linguistics (2000-2001).
Secretary: SIGNLL, Association for Computational Linguistics special interest
group on Natural Language
Learning (1999-2001).
Editorial Board: Machine Learning (1999-2001), Semantic Web Journal.
Action Editor: Journal of Machine Learning Research (2000-2002).
Program co-chair: Fourth Computational Natural Language Learning Workshop
(CoNLL 2000).
Member: DARPA/NSF Question and Answering Roadmap Committee; DARPA/NSF
Summarization Roadmap
Committee; DARPA Translingual Information Detection,
Extraction, and Summarization (TIDES) Evaluation Committee.
Program Committees
Eighteenth International Conference on Machine Learning (ICML) (2001).
Seventeenth International Joint Conference on Artificial Intelligence
(IJCAI) (2001).
First International Conference on Knowledge Capture (K-CAP) (2001).
39th Annual Meeting of the Association for Computational Linguistics (2001).
Second Meeting of the North American Chapter of the Association for Computational
Linguistics (2001).
Fifth Computational Natural Language Learning Workshop (CoNLL) (2001).
Area Chair: The 24th Annual International ACM SIGIR Conference on Research
and Development in Information
Retrieval (2001).
Reviewer: Special issue of Computational Linguistics on anaphora resolution.
Executive Board: SIGDAT, Special Interest Group of ACL for Linguistic
Data and Corpus-based approaches to
NLP.
NSF Review Panel: Knowledge and Cognitive Systems (2000); Human-Computer
Interaction (2001).
Lectures
Noun Phrase Co-reference for Information Extraction. Logic and AI Seminar,
University of Maryland (April,
2001).
Machine Learning for Information Extraction from Unrestricted Text. Alan
Perlis Symposium, Yale University
(April, 2001).
Rapidly Portable Translingual Information Extraction and Interactive Multi-document
Summarization. DARPA
TIDES Meeting (February, 2001).
Overview of Cornell University Projects in Natural Language Understanding.
America On-line (December, 2000).
Publications
"Limitations of Co-training for Natural Language Learning from Large
Datasets." Proceedings of the 2001
Conference on Empirical Methods in Natural Language
Processing (EMNLP-2001), 1-9. Association for
Computational Linguistics (2001). With David
Pierce.
"Multi-document Summarization via Information Extraction." Proceedings
of the First International Conference
on Human Language Technology Research (2001).
With Michael White, Tanya Korelsky, Vincent Ng, David
Pierce, and Kiri Wagstaff.
"Issues, Tasks and Program Structures to Roadmap Research in Question
& Answering" (Q&A). DARPA/NSF
(2000). With J. Burger, V. Chaudhri, R. Gaizauskas,
S. Harabagiu, D. Israel, C. Jacquemin, C. Lin, S.
Maiorano, G. Miller, D. Moldovan, B. Ogden, J.
Prager, E. Riloff, A. Singhal, R. Shrihari, T. Strzalkowski,
E. Voorhees, and R. Weischedel.
"Using Clustering and SuperConcepts within SMART: TREC 6." Information
Processing and Management
36(1):109-131 (2000). With C. Buckley, M. Mitra,
and J. Walz.
"A Cognitive Bias Approach to Feature Selection and Weighting for
Case-based Learners." Machine Learning
41:85-116 (2000).
"Examining the Role of Statistical and Linguistic Knowledge Sources
in a General-knowledge Question-
answering System." Proceedings of the Sixth
Applied Natural Language Processing Conference (ANLP-
2000), 180-187. Association for Computational
Linguistics / Morgan Kaufmann (2000). With V. Ng, D.
Pierce, and C. Buckley.
"Clustering with Instance-level Constraints." Proceedings of
the Seventeenth International Conference on
Machine Learning, 1103-1110. Morgan Kaufmann
(2000). With Kiri Wagstaff.
Integrating Case-based Learning and Cognitive Biases for Machine Learning
of Natural Language." Journal of
Experimental and Theoretical Artificial Intelligence
11:297-337 (1999).
"The Role of Lexicalization and Pruning for Base Noun Phrase Grammars."
Proceedings of the Sixteenth
National Conference on Artificial Intelligence,
423-430. AAAI Press / MIT Press (1999). With David Pierce.
"Noun Phrase Co-reference as Clustering." Proceedings of the
Joint Conference on Empirical Methods in
Natural Language Processing and Very Large Corpora,
82-89. Association for Computational Linguistics
(1999). With Kiri Wagstaff.
Error-driven Pruning of Treebank Grammars for Base Noun Phrase Identification."
Proceedings of the Annual
Conference of the Association for Computational
Linguistics and COLING-98, 218-224. Association for
Computational Linguistics (1998). With David
Pierce.
"Empirical Methods in Information Extraction." AI Magazine
18(4):65-79 (1997).
[On sabbatic leave
2001-2002]
L. Paul Chew
Senior Research Associate
chew@s.cornell.edu
http://www.cs.cornell.edu/Info/People/chew/chew.html
My
primary interest is in geometric algorithms with an emphasis on practical
applications. These practical applications have included placement, motion
planning, shape comparison, vision, sensing, mesh generation, molecular
matching, and protein shape-comparison.
In recent work on protein shape, Klara Kedem and
I have developed a new kind of "consensus shape" for protein
families. This is an analog of the consensus string that is sometimes
used for multiple alignment of proteins. The idea is based, in part, on
our previous work on the Unit-vector Root Mean Square (URMS) distance
for protein shapes. The consensus shape is a pseudo-protein with useful
properties. It is a pseudo-protein because it fails to have certain characteristics
of real proteins. In particular, for the consensus shape, the spacing
between successive alpha carbons is variable, with small distances in
regions where the members of the protein family exhibit significant variation
and large distances (up to the standard spacing of four angstroms) in
regions where the family members agree. Despite this nonprotein-like characteristic,
the consensus shape does preserve structural information. If all members
of a protein family exhibit a geometric relationship between corresponding
alpha carbons then that relationship is preserved in the consensus shape.
In particular, distances and angles that are consistent across family
members are preserved. Thus, the consensus shape provides a compact summary
of the significant strucutural information for a family. We are exploring
the use of the consensus shape (1) as a tool for improved protein threading
for use in protein structure prediction and (2) as a tool for automating
the division of proteins into families and subfamilies.
My work on mesh generation has been motivated
by the finite element method for finding approximate solutions to partial
differential equations. The first step of this method is to create a mesh,
i.e. to divide the given problem region into simple shapes called elements
(usually triangles or quadrilaterals in 2D, tetrahedra or hexahedra in
3D). A number of algorithms have been developed to automate this process,
but most of them don't guarantee the quality of the resulting mesh (e.g.,
a triangle may cross a region boundary or there may be some flat triangles,
leading to poor error bounds). I developed efficient techniques for producing
meshes of guaranteed quality for problems in the plane and for curved
surfaces. The triangles produced are close to equilateral in shape; all
region boundaries are respected; and the user can control the element
density, producing small elements in "interesting" regions and
large elements elsewhere.
I extended this work to produce tetrahedral meshes
for three-dimensional problems. The major difficulty here is to avoid
producing "slivers": tetrahedra with nicely shaped faces but
with near-zero volume. I showed that slivers can be avoided by choosing
each new mesh point randomly within a small specified volume. The randomness
helps; a good mesh point-one that does not form any slivers-can be found
in constant expected time.
This work is being used in a large, multi-disciplinary
project: developing adaptive software for field-driven simulations. In
particular, we focus on computational fracture mechanics and reactive,
multiphase fluid flows. Our goal is to develop principles for building
software systems that can adapt to changing conditions. These conditions
include changes in the desired physics (e.g. we may need to change our
physics model when we discover that vibration is significant), changes
in the desired algorithms (e.g. we may change our solution technique depending
on how quickly we are converging toward a solution), and changes in the
computing environment (e.g. additional processors may become available
or we may lose processors due to processor failure). Other Cornell researchers
working on this project are Keshav Pingali, Steve Vavasis, Paul Stodghill,
and Tony Ingraffea (Civil Engineering), along with participants at Mississippi
State University, Ohio State University, Clark-Atlanta University, and
the College of William & Mary.
Professional Activities
Associate Editor: Pattern Recognition: the Journal of the Pattern Recognition
Society.
Referee: Journal of the Association for Computing Machinery, SIAM Journal
on Scientific Computing.
Publications
"Parallel FEM Simulation of Crack Propagation-challenges, Status,
and Perspectives." Proceedings of Irregular
2000 (2000). With B. Carter, C.S. Chen, G. Heber,
A.R. Ingraffea, R. Krause, C. Myers, P.A. Wawrzynek,
K. Pingali, P. Stodghill, S. Vavasis, N. Chrisochoides,
D. Nave, and G.R. Gao.
"Fast Detection of Common Geometric Substructure in Proteins."
Journal of Computational Biology 6(3):313-
325 (1999). With D. Huttenlocher, K. Kedem, and
J. Kleinberg.
"Unit-vector RMS (URMS) as a Tool to Analyze Molecular Dynamics Trajectories."
Proteins: Structure,
Function and Genetics 37, 554-564 (1999). With
K. Kedem and R. Elber.
Tom Coleman
Professor
Director, Cornell Theory Center
Director, Financial Industry Solutions Center (FISC)
Our
research is concerned with the design and understanding of practical and
efficient numerical algorithms for continuous optimization problems. Our
primary emphasis is the development of algorithms for large-scale optimization,
especially as applied to the area of computational finance.
With colleagues Yuying Li, Peter Mansfield, Arun
Verma, and Shirish Chinchalkar, we are developing a variety of tools and
methods for computational finance in the areas of portfolio management
and options pricing (and hedging). Several Ph.D. students in the Center
for Applied Mathematics are also involved in this work: Cristina Patron,
Yohan Kim, and Changhong He. Yohan Kim completed his Ph.D. dissertation
in May, 2001: Estimation of Smooth Volatility Functions in Option Pricing
Models.
University Activities
Director: Cornell Theory Center.
Director: Financial Industry Solutions Center (55 Broad Street, NYC).
Member: Engineering Dean Search Committee; Cornell Task Force on Genomics;
Program Committee for the Center for Applied Mathematics.
Professional Activities
Chair: SIAM Activity Group on Optimization.
Co-organizer: The 11th Annual Derivatives Securities Conference, New York
(April 27-28).
Organizer: FISC Spring 2000 Workshop Series.
Program Committee: Automatic Differentiation 2000, INRIA, France.
Member: Advisory Board, Brookhaven Center for Data Intensive Computing;
Scientific Program Committee.
Member: Organizing committee for the thematic year at the Fields Institute:
Numerical and Computational
Challenges in Science and Engineering (2001-2002).
Organizer: Proposal for an IMA Special Year on Optimization, Minneapolis,
MN (2002-2003); Seventh SIAM
Conference on Optimization, Toronto, Ontario
(2002).
Editorial Board: Applied Mathematics Letters; SIAM Journal of Scientific
Computing; Computational
Optimization and Applications, Comm. on Applied
Non-linear Analysis, Mathematical Modeling and
Scientific Computing.
Referee/Reviewer: Mathematical Programming; Computational Optimization
and Applications; SIAM Journal of
Optimization; SIAM Journal of Scientific Computing;
Department of Energy, NSF.
Lectures
Dynamic Hedging and a Deterministic Local Implied Volatility Function.
Eleventh Annual Derivatives
Conference, New York (April 28, 2001).
RISK 2001 Europe, Paris France (April 10-11, 2001).
Introduction to Computational Finance in Matlab: A 1-day workshop at FISC-Japan,
Tokyo (March 22, 2001).
A Newton Method for Option Valuation. U. Singapore, Singapore (December
12, 2000).
-. City University of Hong Kong, Hong Kong (December 22, 2000).
Publications
"ADMIT?1: Automatic Differentiation and MATLAB Interface Toolbox."
ACM Transactions on Mathematical
Software 22:150-175 (2000). With Arun Verma.
"Efficiency Improvements for Pricing American Options with a Stochastic
Mesh: Parallel Implementation."
Financial Engineering News, 1-2 (December, 2000).
With Thanos Avranidis, Yuriy Zinchenko, and Arun
Verma.
[On sabbatic leave 2001-2002]
Bob Constable
Professor
Dean for Computing and Information Science
rc@cs.cornell.edu
http://www.cs.cornell.edu/home/rc/
Ph.D. University of Wisconsin-Madison, 1968
We
have been building a system that we call a logical programming environment
(LPE). It provides substantial automation in the design, coding, verification,
and evolution of large software systems. Generally an LPE will integrate
programming languages and logics. In our case we integrate the ML programming
language and a programming logic based on type theory. Reasoning about
ML programs is founded on type theoretic semantics for ML. The LPE also
integrates a compiler and a theorem prover. We use the latest version
of Nuprl as the prover.
Over the past year we have deployed our prototype
LPE to support the Ensemble group communication system that Ken Birman,
Robbert van Renesse, and their students have built. The LPE provides automatic
code transformations that improve performance in a way that is guaranteed
not to introduce errors. The LPE also supports the design and coding of
new adaptive protocols that are part of the Spinglass project.
The Nuprl 5 system is a major re-implementation
of Nuprl 4; its design is based on communicating processes that synchronize
around a logical database that we call "the Library." The Library
stores definitions, theorems, conjectures, proofs, algorithms, proof tactics,
and commentary that is linked to the formal mathematics. We released the
first version of Nuprl 5 last summer, with a debut at CADE in June involving
the whole design and implementation team (Stuart Allen, Rich Eaton, Christoph
Kreitz, Lori Lorigo, and me). Nuprl 5 supports multiple proof engines
and multiple editors. It also integrates an automatic theorem prover,
called the JProver, built by C. Kreitz, Jens Otten, and Stephan Schmitt.
The Library includes over ten thousand theorems.
Many of these are used in system verification, but a large number are
from general mathematics. These general theorems are a valuable resource.
We are funded by ONR to further develop and explore the concept of a formal
digital library of formal constructive mathematics built around these
theorems. We will generalize our mechanisms to allow many users to contribute
to the Library using other theorem provers such as ACL2, HOL and PVS.
We are also working on a more experimental LPE
called MetaPRL, which started with Jason Hickey's thesis and now involves
many people but especially Aleksey Nogin and Alexsey Kopylov. This system
is built entirely in OCaml and supports OCaml as its programming language.
It is coded for efficiency as well as modularity, and at some tasks it
is over two orders of magnitude faster than Nuprl 5. It also supports
multiple programming logics. Nuprl 5 and MetaPRL share mathematics libraries.
The two theorem provers are used in a variety
of other projects as well, including the creation of formal courseware
by S. Allen, the translation of formal proofs into natural language by
Amanda Holland-Minkley, the automatic analysis of the computational complexity
of higher-order programs by Ralph Benzinger, and efficient reflection
being designed and implemented by Eli Barzilay. We follow the work of
Greg Morrisett and his students on new ML compilers and on typed assembly
language. We plan to use the LPE to broadly support research on language-based
security in the department and at the new Information Assurance Institute,
including the work of Dexter Kozen, Andrew Myers, and Fred Schneider.
University Activities
Dean: Computing and Information Science.
Committees: Applied Math Policy; Cognitive Studies Executive Committee;
Theory Center Executive Committee.
Professional Activities
Advisory Council: Princeton University Department of Computer Science.
Editor: Journal of Logic and Computation; Formal Methods in
System Design; Journal of Symbolic
Computation.
Director: NATO Summer School, Marktoberdorf, Germany.
General Committee Member: LICS.
Lectures
How Computers Think. Dean's Forum, Faculty of Natural Sciences, Ben-Gurion
University (June, 2001).
Formal Complexity Classes: An Approach to Automating Computational Complexity
Analysis. Cornell
University (May, 2001). With Ralph Benzinger.
How Nuprl Reasons. University of Delaware (May, 2001).
Taking a MEGABYTE: Cornell in the Information Age. University of Delaware
(May, 2001).
How Nuprl Reasons. Yale University (February, 2001).
Taking a MEGABYTE: Cornell in the Information Age. Cornell University
(February, 2001).
Representing the Faculty of Computing and Information. Cornell University
(September, 2000).
How Computers Think. Cornell University (September, 2000).
Computer Science: Achievements and Challenges Circa 2000. Cornell University
(March, 2000).
Publications
"An Experiment in Formal Design Using Meta-properties. In Proceedings
of DARPA Information Survivability
Conference and Exposition II (DISCEX 2001), IEEE
Computer Society Press (June, 2001). With C. Kreitz,
M. Bickford, and R. van Renesse.
"Protocol Switching: Exploiting Meta-properties." In Proceedings
of the International Workshop on Applied
Reliable Group Communication (WARGC 2001) (April,
2001). IEEE Computer Society Press. With C.
Kreitz, X. Liu, R. van Renesse, and M. Bickford.
"Computational Complexity and Induction for Partial Computable Functions
in Type Theory." In Reflections: A
Collection of Essays in Honor of Solomon Feferman,
Association for Symbolic Logic (2001). With K. Crary.
"Constructively Formalizing Automata." In Proof, Language
and Interaction: Essays in Honour of Robin Milner,
MIT Press, 213-238 (2000). With P.B. Jackson,
P. Naumov, and J. Uribe.
"Nuprl's Class Theory and its Applications." In Foundations
of Secure Computation, F.L. Bauer and R.
Steinbruggen, editors. IOS Press, 91-115 (2000).
"Types in Logic, Mathematics and Programming." In Handbook
of Proof Theory, S. R. Buss, editor. Elsevier
Science B. V., 684-785 (1998).
"The Structure of Nuprl's Type Theory." In Logic of Computation,
Springer-Verlag, (1997).
Implementing Mathematics with the Nuprl Development System. Prentice-Hall
(1986). With S. Allen, et. al.
Alan Demers
Professor
ademers@cs.cornell.edu
Ph.D. Princeton University, 1975
My
current research concerns aspects of weakly-consistent data replication
in databases and distributed systems. With Ken Birman, Robbert van Renesse,
Johannes Gehrke, and others, I am studying randomized "gossip protocols."
Such protocols are highly fault-tolerant and, when properly designed,
extremely scalable as well. We are studying convergence properties of
several flat and hierarchal versions of the basic protocols tailored to
specific application requirements.
My particular focus is approximate evaluation
of aggregate queries in such a system. We are studying age distributions
of gossiped data in order to prove probabilistic bounds on the quality
of aggregate query results. Alternatively, we can use this approach to
bound the latency required to probabilistically guarantee a client-specified
degree of consistency.
We are considering classes of "resource location"
or "anomaly detection" problems, in which query results are
site-specific and depend on distance and subsumption. Such problems can
have efficient and highly scalable solutions using gossip partner choice
distributions based on the distance between sites.
Finally, we are studying graph constructions for
which flooding or deterministic gossip partner choices can be used, leading
to reduced overhead while still retaining most of the desirable properties
of randomized gossip.
The above is related to my previous work on the
Clearinghouse and Bayou projects at Xerox PARC. I am also doing work supported
by Oracle on asynchronous update-anywhere replication in a more traditional
database setting. This involves algorithms for scheduling/reordering update
propagation between sites to improve throughput while preserving eventual
consistency and bounded inconsistency during propagation.
Recent Papers
"Logarithmic Harary Graphs." ICDCS International Workshop on
Applied Reliable Group Communication,
Phoenix, Arizona (April, 2001). With K. Jenkins.
"Spatial Gossip and Resource Location Protocols." Proceedings
of the 33d ACM Symposium on Theory of
Computing, Crete (July, 2001). With D. Kempe,
and J. Kleinberg.
Ron Elber
Professor
ron@cs.cornell.edu
http://www.cs.cornell.edu/ron/old_webpage-ron/index_ron.html
Ph.D. Hebrew University, Jerusalem, 1984
My
research is in the field of Computational Molecular Biology. We develop
computer algorithms to study sequences, structures, dynamics, and function
of proteins and apply these methods to a variety of biological problems.
Our techniques are implemented in the systems MOIL and LOOPP, available
on the web http://www.tc.cornell.edu/CBIO.
My current research directions include: mean field
approaches for global optimization and structure prediction (Locally Enhanced
Sampling). Structures are often determined by an optimization of an energy
function. I introduced mean field approaches that modify the target function
and make it more accessible to global optimization. We have applied these
techniques to determine conformations of short peptides and to refine
low-resolution structures of proteins. These approaches are implemented
into MOIL.
We are also working on development of folding
potentials using linear programming. An ideal folding potential assigns
the lowest energy to the correct three-dimensional structure of a protein.
All other structures must have higher energies. The design of folding
potentials relies on considerable human intuition and many trials and
errors. I developed an automated protocol that "learns" and
improves the quality of the current potential energy. We used this protocol
to prove that the widely used pairwise interactionmodel cannot recognize
exactly correct protein folds. Based on these studies, a novel threading
algorithm was designed and implemented in the program LOOPP. In a threading
algorithm a sequence is matched with a structure. In a recent article
in Science, we published an intriguing application of this program. We
suggested an evolutionary link between a gene that controls the size of
the tomato fruit and a protein that participates in controlling cell growth
and division. Malfunction of this protein causes cancer in humans (joint
work with Steve Tanksley's group).
Another project concerns extending the time scale
of simulations. One of the striking observations in dynamics of biological
molecules is the extremely large time scale they covered. Initiation by
light absorption of biochemical processes is very rapid (femtoseconds),
while protein folding is slow (milliseconds to minutes). Current simulation
approaches (Molecular Dynamics (MD)) are restricted to nanoseconds (10-9
seconds). I developed a stochastic path integral formulation that provides
a numerically stable trajectory for almost any arbitrary time step. We
apply the new algorithm to study activation of proteins (the R->T transitions
in hemoglobin, microseconds) and to protein folding (folding of C peptide,
tens of nanoseconds). The method provides systematic approximations to
the dynamics and is more efficient than MD by orders of magnitude. It
is available in MOIL.
Professional Activities
Acting head: NIH resource for parallel computing at the Cornell Theory
Center.
Committees: Statistical and Computational Genomics Committee; Computational
Biology Committee for the collaborative efforts at Cornell, Rockefeller,
and Sloan Kettering Institutes; Cornell Life Science Advisory Board;
Planning Committee for Life Science and Technology
Building; Theory Center committee.
National Committees: NIH study sections; NSF study section; Reviewer for
the State of Texas; Chair:
workshop on protein dynamics, Telluride (August,
2001).
Lectures
Protein Recognition by Threading. DIMACS, Rutgers (March, 2001).
Parallel Computations of Trajectories. SIAM (March, 2001).
Long Time Dynamics of Proteins. University of Pennsylvania (February,
2001).
Long Time Dynamics and Protein Recognition by Threading. IBM Watson (February,
2001).
Long Time Dynamics of Biomolecules. Florida State, Computational Biophysics
(January, 2001).
Protein Recognition by Threading. CUNY (December, 2000).
Protein Recognition by Threading. University of Maryland (October, 2000).
Long Time Dynamics of Biomolecules. NYU (October, 2000), M3.
Publications
"Protein Recognition by Sequence-to-structure Fitness: Bridging Efficiency
and Capacity of Threading Models."
Submitted to Advances in Chemical Physics, by
invitation. With Jaroslaw Meller.
"The Enzymatic Circularization of a Malto-octaose Linear Chain Studied
by Stochastic Reaction Path
Calculations on Cyclodextrin Glycosyltransferase."
Proteins, Structure, Function and Genetics 43:327-335 (2001). With Joost
C.M. Uitdehaag, Bart A. van der Veen, Lubbert Dijkhuizen, and Bauke W.
Dijkstra.
"Cloning, Transgenic Expression and Function of fw2.2: a Quantitative
Trait Locus Key to the Evolution of
Tomato Fruit." Science 289:85-88 (2000).
With A. Frary, C. Nesbitt, A. Frary, S. Grandillo, E. van der
Knaap, B. Cong, J. Liu, J. Meller, K.B. Alpert,
and S.D. Tanksley.
"Distance Dependent Pair Potential for Protein Folding: Results from
Linear Optimization." Proteins, Structure,
Function and Genetics 41:40-46 (2000). With D.
Tobi.
"Probing the Role of the Local Propensity in Peptide Turn Formation."
International Journal of Quantum
Chemistry 80:1125-1128 (2000). With D. Mohanty,
and D. Thirumalai.
Geri Gay
Professor
FCI,
Joint with Communications
gkg1@cornell.edu
http://www.comm.cornell.edu/faculty/gay.html
Ph.D. Cornell University, 1985
Iam
the director of the Human Computer Interaction Group (HCI Group) and a
professor of communication at Cornell University. The HCI Group is a research
and development group whose members design and research the use of computer-mediated
learning environments. My research interests focus on cognitive and social
issues for the design and use of interactive communication technologies.
Past research has explored navigation issues, knowledge management, mental
models and metaphors, knowledge representations, collaborative work and
learning, and system design.
I have received funding for my research
and design projects from the National Science Foundation (NSF), the National
Endowment for the Humanities (NEH), the Mellon Foundation, Intel, Microsoft,
IBM, Getty, and several private donors. I teach courses in interactive
multimedia design and research, computer-mediated communication, human-computer
interaction, and the social design of communication systems.
Honors/Awards
NYS Chancellor's Award for Excellence 2001.
Innovative Teaching Award 2000.
Current Projects
NASA and AT&T Advanced Technology for Learning projects.
Intel Museum Context Aware Computing Project.
Intel and NSF studies on the use of wireless computing, covered in Chronicle
of Higher Education, USA Today,
Newsweek, The New York Times, Globe and
Mail, and NPR.
Lectures
American Educational Research Association, International Communication
Association; ACM Multimedia; Japanese Private University Association.
Publications
Articles in Journal of Computer-Mediated Communication; Journal of
Research on Computing in Education; Journal of Educational Technology;
Journal of Educational Computing Research; Journal of Educational Psychology;
International Journal of HCI; ACM Digital Libraries; Journal of Information
Technologies.
Johannes Gehrke
Assistant Professor
johannes@cs.cornell.edu
http://www.cs.cornell.edu/johannes/
Ph.D.
University of Wisconsin-Madison, 1999
My
primary research interest is in the development of new data mining and
database technology. My group is currently involved in three projects:
The Himalaya
Data Mining Project, the Cougar
Sensor Database System, and the Amazon
Stream Processing Project.
In the Himalaya Data Mining Project we develop
new data mining functionality, and we work on techniques to make the resulting
data mining models more understandable to the user. As an example, consider
classification trees, a data mining model that is supported in nearly
all commercial data mining suites. In recent research we have shown that
a large class of classification tree construction algorithms is biased
(including most algorithms used in commercial tools), thus, users could
draw incorrect conclusions from the resulting "incorrect" classification
tree. Our methods can provably eliminate this bias from any existing split
selection method. Other recent results include the fastest published algorithm
for mining long market baskets, and new methods for mining long sequential
patterns.
The widespread deployment of sensors and
mobile devices is transforming our physical environment into a computing
platform. There is now computing power on every device, and emerging networking
techniques ensure that devices are interconnected and accessible from
local or wide-area networks. This is a distributed database system of
unprecedented scale. In the Cougar Sensor DatabaseSystem, we develop database
technology for tasking, mining, and monitoring such a large number of
distributed data sources. We have implemented the first generation of
the Cougar Device Database System, where we leverage the processing power
on the devices to push query processing directly to the data sources.
Different query processing strategies allow us to balance resource usage,
accuracy, and speed of query answers. Our current research focuses on
distributed and fault tolerant query processing and meta-data management.
In many applications, for example in intrusion detection, sensor networks,
and network management, data arrive in streams, and the large volume of
such high-speed data streams makes storage and offline processing of the
data infeasible. In the Amazon Stream Processing Project, we are developing
query processing techniques for long running queries over infinite data
streams. The main difficulty here is the new model of computation: Instead
of being able to re-read data many times and to perform expensive offline
computation on a static dataset, we need to compute query answers and
maintain summary statistics in an online fashion. Our recent results include
computation of correlated aggregates and quantiles over data streams.
Honors/Awards
IBM Faculty Development Award (2000, 2001).
James and Mary Tien Excellence in Teaching Award (2001).
University Activities
Member: Space Committee, Department of Computer Science; Faculty Search
Committee, School of
Operations Research and Industrial Engineering;
faculty Search Committee, The Computational and
Statistical Genomics Trust.
Profesional Activities
Program Committees:
Twenty-sixth International Conference on Very Large Databases (VLDB),
Cairo, Egypt (September, 2000).
Demonstrations Committee.
Seventeenth IEEE International Conference on Data Engineering (ICDE 2001),
Heidelberg, Germany (April,
2001).
Fourth International Workshop on Parallel and Distributed Data Mining.
Workshop held in conjunction with the
15th International Parallel and Distributed
Processing Symposium, San Francisco, CA (April, 2001).
Twentieth ACM SIGMOD Conference (SIGMOD 2001), Santa Barbara, CA (May,
2001).
ACM SIGMOD Workshop on Research Issues in Data Mining and Knowledge Discovery
(DMKD 2001) held in
cooperation with SIGMOD 2001. Santa Barbara,
CA (May, 2001). Workshop Co-chair.
Eighteenth International Conference on Machine Learning (ICML 2001), Williams
College, MA (June, 2001). Sixth ACM SIGKDD Conference (KDD 2001), San
Jose, CA (August, 2001).
Twelfth International Conference on Software Engineering and Knowledge
Engineering, Chicago, IL (July, 2000).
Sixth ACM SIGKDD International Conference on Knowledge Discovery and Data
Mining (KDD 2000). Boston,
MA (August, 2000).
Editorial Boards:
Knowledge and Information Systems.
Journal of Database Management.
Lectures
An Introduction to Data Mining. Air Force Research Laboratory, Rome, NY
(September 12, 2000).
An Overview of Modern Data Mining Technology. Workshop at the Financial
Industry Solutions Center (FISC)
New York (November 8, 2000).
The Infrastructure of Electronic Commerce. Lectures on Database Technology
and Data Mining. Johnson
Graduate School of Management, Cornell
University (January, 2001).
Honest Classification Trees. IBM Watson Research Center, Yorktown, NY
(March, 2001).
Panel Manager for "Storage-A Crowded Place?" Panel at the 2001
Leadership in the Technology Marketplace
Symposium, Cornell Johnson Graduate School
of Management, Ithaca (April, 2001).
Querying the Physical World. DARPA Sensor Information Technology PI Meeting.
St. Petersburg, FL (April,
2001).
Mining Very Large Databases. Invited talk at the 33rd Symposium on the
Interface of Computing Science and
Statistics, Costa Mesa, CA (June, 2001).
Publications
"RAINFOREST - A Framework for Fast Decision Tree Construction of
Large Datasets. In Data Mining and
Knowledge Discovery 4(2/3):27-162 (July,
2000). With Raghu Ramakrishnan, and Venkatesh Ganti.
"Querying the Physical World." In IEEE Personal Communications,
special issue on Smart Spaces and
Environments (October, 2000). With Philippe
Bonnet, and Praveen Seshadri.
"Towards Sensor Database Systems." In Proceedings of the Second
International Conference on Mobile Data
Management, Hong Kong, China (January,
2001). With Philippe Bonnet, and Praveen Seshadri.
"DEMON: Mining and Monitoring Evolving Data." In IEEE Transactions
on Knowledge and Data Engineering 13(1):50-63
(January/February 2001). With Venkatesh Ganti, and Raghu Ramakrishnan.
"MAFIA: A Maximal Frequent Itemset Algorithm for Transactional Databases."
In Proceedings of the 17th
International Conference on Data Engineering,
Heidelberg, Germany (April, 2001). With Doug Burdick, and
Manuel Calimlim.
"On Computing Correlated Aggregates Over Continual Data Streams."
In Proceedings of the 2001 ACM
SIGMOD International Conference on Management
of Data, Santa Barbara, CA (May, 2001). With Flip
Korn, and Divesh Srivastava.
"Query Optimization In Compressed Database Systems." In Proceedings
of the 2001 ACM SIGMOD
International Conference on Management
of Data, Santa Barbara, CA (May, 2001). With Zhiyuan Chen,
and Flip Korn.
"Bias Correction in Classification Tree Construction." In Proceedings
of the Seventeenth International
Conference on Machine Learning (ICML 2001),
Williams College, MA (June, 2001). With Alin Dobra.
Carla Gomes
Research Associate
Director, Intelligent Information Systems Institute (IISI)
gomes@cs.cornell.edu
http://www.cs.cornell.edu/gomes
Ph.D. University of Edinburgh, 1993
My
research interests are centered around the integration of methods from
artificial intelligence and operations research for solving hard combinatorial
problems. I consider applications in areas ranging from combinatorial
design, planning and scheduling, reasoning, multi-agent systems, and machine
learning. Recently, I have focused on randomized search techniques. In
this work, I study so-called heavy-tailed distributions that characterize
complete randomized search methods. A promising way of exploiting heavy-tailed
behavior is by combining a suite of search methods into a portfolio, running
on a distributed compute cluster. It can be shown that such portfolios
dramatically reduce the expected overall computational cost, thereby allowing
us to solve large, previously unsolved combinatorial problems. Another
recent research direction (joint work with groups at the University of
Washington and Microsoft Research) involves the use of machine learning
techniques and Bayesian models to develop effective adaptive algorithmic
strategies given bounded computational resources.
I also established and direct the newly formed Intelligent Information
Systems Institute (IISI) at Cornell. The mission of the institute is to
foster research in computation and data intensive methods for intelligent
decision making systems. See www.cis.cornell.edu/iisi.
Professional Activities
Director, Intelligent Information Systems Institute (IISI).
Guest Editor, Journal of Knowledge Engineering Review, Cambridge
Press.
Guest Editor, Artificial Intelligence Journal.
Editorial Board, Journal of Knowledge Engineering Review.
Editorial Board, International Journal AI Tools (IJAIT).
Co-chair, AAAI Symposium on Uncertainty in Computation, Boston, MA (2001).
Co-chair, AAAI Workshop on Leveraging Probability and Uncertainty in Computation,
AAAI (2000).
Member, Advisory Committee International Scientists, Ministry of Science
and Technology, Portuguese Government, Presidency of European Union (2000).
Member, Program Committee, SAT, Boston, MA (2001).
External Examiner, Ph.D. Thesis of Ramon Bejar, Univ. of Leida, Barcelona,
Spain.
Reviewer for 7th Int. Joint Conference on Artificial Intelligence (IJCAI);
Journal of Automated Reasoning; Journal
of Artificial Intelligence Research; Constraints: An International
Journal; Discrete Applied Mathematics.
Lectures
Structure, Duality, and Randomization: Common Themes in AI and OR.
-. Broad Area Colloquium, Stanford University, Stanford, CA (November,
2000).
-. AI Seminar, SRI, Palo Alto, CA (November, 2000).
-. Research Seminar, NASA/Ames, Mountain View, CA (November, 2000).
-. Colloquium, Univ. of Lisbon, Lisbon, Portugal (March, 2001).
Survey of Information Retrieval and Knowledge Representation, 3 lectures
at AFRL/IF, Rome, NY (November,
2000).
Vision and Directions for the Intelligent Information System Institute,
AFRL/IF, Rome, NY (February, 2001).
Impact of Structure on Complexity. MURI /AFOSR meeting on Coop. Control
of Distributed Autonomous
Vehicles in Adversarial Environments, UCLA,
Los Angeles, CA (May, 2001).
Structure and Complexity in the Virtual Transportation Company. Meeting
on Taskable Agent Software Kit,
DARPA, Sante Fe, NM (April, 2001).
Controlling Computational Cost. Meeting on Autonomous Negotiation Teams,
DARPA, Lake Tahoe, CA (May,
2001).
Publications
"On the Intersection of AI and OR." Journal of Knowledge
Engineering Review 16(1) (2001).
"Algorithm Portfolios." Artificial Intelligence Journal
126(2001). With B. Selman.
"A Bayesian Approach to Tackling Hard Computational Problems."
Proc. 17th Conf. on Uncertainty and
Artificial Intelligence (UAI-2001), Seattle,
WA (2001). With E. Horvitz, Y. Ruan, H. Kautz, B. Selman, and M.
Chickering.
"Balance and Filtering in Structured Satisfiable Problems. Proc.
17th Intl. Conf. on Artificial Intelligence (IJCAI-
2001), Seattle, WA (2001). With H. Kautz,
Y. Ruan, D. Achlioptas, B. Selman, and M. Stickel.
"Extending the Reach of SAT with Many-valued Logics." Electronic
Notes in Discrete Mathematics 9, Elsevier
Science Publ. (2001). With R. Bejar, A.
Cabiscol, C. Fernandez, and F. Manya.
"An Application of Randomization and Restarts in Proof Planning."
Proc. of the 6th European Conference on
Planning (ECP-01), Toledo, Spain (2001).
With A. Meier, and E.Melis.
"Extending the Reach of Proof Planning by Randomization and Restart
Techniques." Future Directions in
Automated Reasoning, IJCAR Workshop,
Siena, Italy (2001). With A. Meier and E. Melis.
"Generating Hard Feasible Schedules. Proc. of the 6th European Conference
on Planning (ECP-01), Toledo,
Spain (2001). With J. Argelich, R. Bejar,
A. Cabiscol, C. Fernandez, and F. Manya.
"Heavy-tailed Behavior and Randomization in Proof Planning. Model-based
Validation of Intelligence, AAAI
2001 Spring Symposium Series, Stanford,
CA (2001). With A. Meier and E. Melis.
"Distribute Constraint Satisfaction in a Wireless Sensor Tracking
System. Proc. Workshop on Distributed
Constraint Reasoning (CONS-2), IJCAI-2001,
Seattle (2001). With R. Bejar, B. Krishnamachari, and B.
Selman.
"Heavy-tailed Phenomena in Satisfiability and Constraint Satisfaction
Problems. Journal of Automated
Reasoning 24(1/2):67-100 (2000). With
B. Selman, N. Crato, and Henry Kautz). Results featured in
Science News (2000).
"Artificial Intelligence and Operations Research: Challenges and
Opportunities in Planning and Scheduling and
Operations Research. Journal of Knowledge
Engineering Review 15(1) (2000).
Donald Greenberg
Professor and Member of the FCI,
the Johnson School of Management,
the Department of Architecture, and the
Graduate Field of Computer Science
dpg@graphics.cornell.edu
http://www.graphics.cornell.edu/people/director.html
Ph.D. Cornell University, 1968
Iam
one of the pioneers in the emerging field of computer graphics, having
served as a leading researcher and teacher in the field since 1965. My
research is primarily concerned with physically based image synthesis
and with applying graphic techniques to a variety of disciplines. My specialties
include color science, parallel processing, and realistic image generation.
My application work now focuses on medical imaging, architectural design,
perception, digital photography, and real-time photorealistic image generation.
Consistent with the interdisciplinary nature
of the field of computer graphics, I am a member of Cornell's faculty
in Johnson Graduate School of Management, the Department of Computer Science,
and the Department of Architecture. In recent years I have taught courses
in computer graphics, computer-aided architectural design, digital photography,
and disruptive technologies.
I was the founding director of the NSF Science
and Technology Center for Computer Graphics and Scientific Visualization,
now in its eleventh year. I am the director of the Program of Computer
Graphics and former director of the Computer-aided Design Instructional
Facility at Cornell.
I have published more than 200 articles
on computer graphics, and many of my students have been highly recognized
in the field, including several who have received the SIGGRAPH Achievement
Award and others who have received Hollywood Oscars.
In 1987, I received the ACM Steven Coons
Award, the highest honor in the field, for my outstanding creative contributions
in computer graphics. I also received the National Computer Graphics Association
Academic Award in 1989. In 1997 I received the ASCA Creative Research
Award in Architecture. An honorary doctoral degree from New Jersey Institute
of Technology was presented to me in 1999.
Professional Activities
Member: National Academy of Engineering.
Fellow: ACM and International Association of Medical and Biological Engineering.
Lectures
Disruptive Histories of Our Future. Cornell JGSM Reunion 2001, Cornell
University (June 9, 2001).
Art & Design for Living. Cornell University, Parents Visit (April
20, 2001).
Virtual Environments of the 21st Century. Cornell Association of Professors
Emeriti, Cornell University (April
19, 2001).
Rendering History & Progress. STC Lecture, Program of Computer Graphics,
Cornell University (April 17,
2001).
The Real Challenge for Architecture in a Virtual World. Architecture Department,
University of Virginia,
Charlottesville, VA (April 5, 2001).
Rendering. EAG 2001, Boston, MA (April 3, 2001).
Working Today on Tomorrow's Design Software. SOM Lecture Series, NY (February
15, 2001).
B-schools: A Case History of Our Future. MBA Leadership 2001 Conference,
New Orleans, Louisiana (January
25, 2001).
Distance Learning. Cornell Club of Eastern Florida, Delray Beach, FL (December
6, 2000).
Great Ideas for Computer Science. Lecture, ComS 150, Computer Science,
Cornell University (October 18,
2000).
Technology & Design Practices. Real-time Workshop on Technology and
Design Practice, Program of
Computer Graphics, Cornell University (October
8, 2000).
Tomorrow's Internet and Design Software. Proceedings: Emerging Information
Technologies for Facilities, NAS,
FCC, Washington D.C. (October 20, 2000).
How Do We Prepare Our Students for the Future? Architecture Summer School:
Architecture Department,
Cornell University (July 12, 2000).
Publications
"Spatiotemporal Sensitivity and Visual Attention For Efficient Rendering
of Dynamic Environments." ACM
Transactions on Graphics (2001). With Hector
(Yang-Li) Yee, and Sumanta N. Pattanaik.
"Field Trip to Ithaca, N.Y.: Autodesk Development Team Refining Sketching
Advantages of Architectural
Studio." Design Architecture.com (June
4, 2001). With Wendy Talarico.
"Lighting the Way: A Conversation with Don Greenberg of Cornell's
Program in Computer Graphics." Cadence
Web (http://www.cadenceweb.com/features/interviews/greenberg.html),
1-2 (2001).
"Tomorrow's Internet and Design Software." Symposium: Emerging
Information Technologies for Facilities,
NAS, FCC, Washington D.C. (October 20,
2000).
"Once and Future Graphics Pioneer." Architecture Week
(18):1-7 (September, 2000). With B. J. Novitski.
"Time-dependent Visual Adaptation for Realistic Image Display."
Computer Graphics Proceedings, Annual
Conference Series, ACM SIGGRAPH, 47-53(July,
2000). With Sumanta N. Pattanaik, Jack Tumblin, and Hector Yee.
"Toward a Psychophysically Based Light Reflection Model for Image
Synthesis." Computer Graphics Proceedings, Annual Conference Series
ACM SIGGRAPH, 55-64 (July, 2000). With Fabio Pellacini, and James A. Ferwerda.
"A Lab Ahead of its Time: Cornell Graphics Lab Sets High Standards."
Architectural Record, 198-204 (June, 2000). With B. J. Novitski, and Moreno
A. Piccolotto.
"Approximate Visibility for Illumination Computations using Point
Clouds." Program of Computer Graphics Technical Report, Cornell University
(June 1, 2000). With Philip M. Dutre, and Parag Tole.
"A System for 3D Conceptual Modeling for Architectural Design."
Program of Computer Graphics Technical Report, Cornell University (January
3, 2000). With Moreno Piccolotto, Sebastian Fernandez, Kavita Bala, and
Michael Malone.
"Interactive Direct Lighting in Dynamic Scenes." Program of
Computer Graphics Technical Report, Cornell University (January 2, 2000).
With Sebastian Fernandez, Kavita Bala, and Moreno Piccolotto.
Zygmunt Haas
Associate Professor
Member of the School of Electrical and Computer Engineering
and the Graduate Field of Computer Science
haas@cs.cornell.edu
http://www.ee.cornell.edu/$\sim$haas/wnl.htm
Ph.D. Stanford University
My
research is in the area of mobile and wireless systems and networks. Selected
examples of the projects that are conducted in my Wireless Network Laboratory
(WNL) are: ad-hoc networks (routing, medium access control, security,
etc.), quality of service, cross-layer protocol design, mobile web access,
multicasting, and mobility management.
Memberships
Professional Societies: IEEE Communications Society; IEEE Vehicular Technology;
Association for Computing Machinery (ACM); Special Interest Group on Mobile
Communications (SIGMOBILE).
Awards/Honors
Michael Tien '72 Award, Cornell College of Engineering, Excellence in
Teaching Award (September, 2000).
University Activities
Member, Ad-hoc Tenure Promotion Review Committee, Computer Science Department,
Cornell University;
Computing Policy Committee (CPC), College
of Engineering, Cornell University.
EE Policy Committee, School of Electrical and Computer Engineering, Cornell
University (2000).
Member of the Committee on "Bits On Our Minds 2001 (BOOM '01).
Professional Activities
Editorial Board: IEEE Transactions on Networking.
Editorial Board: IEEE Communications Magazine.
Organizer and chair of the session on "Outrageous Opinions"
at MobiHoc '01, The ACM Symposium on Mobile
Ad-hoc Networking & Computing, Long
Beach, CA (October 4-5, 2001).
Member: IASTED (The International Association of Science and Technology
for Development) Technical
Committee on Telecommunication.
Member:ACM Mobicom Steering Committee.
Chair of the
IEEE Technical Committee on Personal Communications (TCPC).
Vice-chair of the IEEE Technical Committee on Personal Communications
(TCPC).
Editorial Board of the journal Wireless Communications and Mobile Computing,
John Wiley & Sons.
Guest Editor: Wireless Personal Communication Journal, special
issue on Multimedia Network Protocols and
Enabling Radio Technologies.
Editorial Board: ACM/Baltzer Wireless Networks.
Editorial Board: Journal of High Speed Networks.
Program Committee: IEEE Symposium on Ad-hoc Wireless Networks (SAWN),
in conjunction with IEEE
GLOBECOM 2001, San Antonio, TX (November
25-29, 2001).
Program Committee member and session chair, Milcom'01, McLean, VA (October
28-31, 2001).
Committee member: Wireless Communications and Networking Conference 2002
(WCNC'02), Orlando, FL
(March 18-21, 2002).
Program Committee: European Wireless 2002, Next Generation Wireless Networks:
Technologies, Protocols,
Services and Applications, Florence, Italy
(February 26-28, 2002).
Program Committee: 11th IEEE Workshop on Local and Metropolitan Area Networks,
Boulder, CO (May 18,
2001).
Program Committee: IEEE Wireless Networks and Mobile Computing Workshop,
Phoenix, AZ (April 16-19, 2001).
Program Committee: ACM/IEEE MobiCom'2000, Boston, MA (August 6-11, 2000).
Program Committee: First IEEE Workshop on Mobile Ad HOC Networking and
Computing Workshop
(MobiHOC), Boston, MA (August 11-12, 2000).
NSF reviewer and panelist.
Lectures
Research in the Wireless Networks Laboratory at Cornell. Department of
Electrical Engineering, Columbia
University (April 23, 2001).
Research in the Wireless Networks Laboratory at Cornell. Communication
Systems Department, Swiss
Federal Institute of Technology Lausanne
(EPFL) (December 11, 2000).
Publications
"The Zone Routing Protocol: A Hybrid Framework for Routing in Ad-hoc
Networks." Ad-hoc Networks, Charlie
Perkins, editor. Addison Wesley (2001).
With M. R. Pearlman.
"A Communication Infrastructure for Smart Environments - A Position
Article." IEEE Personal Communications
Magazine, special issue on "Networking
the Physical World," 6-10 (October , 2000).
"Predictive Distance-based Mobility Management for PCS Networks."
2000 Cornell Summer Workshop on
Information Theory (Bergerfest), Ithaca,
NY (August 18-19, 2000). And B. Liang.
"On the Impact of Alternate Path Routing for Load Balancing in Mobile
Ad-hoc Networks." First Annual
IEEE/ACM Workshop on Mobile Ad-hoc Networking
& Computing, MobiHOC'2000, Boston, MA (August
11, 200). With M. R. Pearlman, P. Scholander,
and S. S. Tabrizi.
"A Decision-theoretic Approach to Resource Allocation in Wireless
Multimedia Networks." Fourth International
Workshop on Discrete Algorithms and Methods
for Mobile Computing, DIALM 2000, Boston, MA (August
11, 2000). And J. Y. Halpern, L. Li, and
S. B. Wicker.
"Securing Ad-hoc Networks." IEEE Network Magazine 13(6)
(November/December 1999) With L. Zhou.
"Determining the Optimal Configuration for the Zone Routing Protocol."
IEEE Journal on Selected Areas in
Communications (JSAC), issue on Ad-hoc
Networks 17(8):1395-1414 (August, 1999). And M. R.
Pearlman.
"The Dynamic Packet Reservation Multiple Access Scheme for Multimedia
Traffic." ACM/Baltzer Mobile
Networks Applications 4:87-99 (1999). With
D. A. Dyson.
"Ad-hoc Location Management using Quorum Systems." IEEE Transactions
on Networking, ACM/IEEE
Transactions on Networking (April, 1999).
And B. Liang.
"The Multiply-detected Macrodiversity Scheme for Wireless Cellular
Systems." IEEE Transactions on
Vehicular Technology 47(2) (May, 1998).
And C-P. Li.
New Patent Applications
"ITAMAR - Independent Tree Ad-hoc Multicast Routing." Cornell
Research Foundation, Application number: D-
2823 - Haas. And M. S. Sajama.
"COCA: A Secure Distributed On-line Certification Authority."
Cornell Research Foundation, Application
number: D-2732A - Haas. With F. Schneider,
L. Zhou, and R. van Renesse.
"Adaptive Power Control in Wireless Ad-hoc Networks." Cornell
Research Foundation, Application number: D-
2507 - Haas. And Miguel Sanchez.
"Routing and Mobility Management Protocols for Ad-hoc Networks."
Cornell Research Foundation, Application
number: D-2191 - Haas.
Joseph Halpern
Professor, and Co-director:
Cognitive Studies Program
halpern@cs.cornell.edu
http://www.cs.cornell.edu/home/halpern/
Ph.D. Harvard University, 1981
My research is concerned with representing and reasoning about knowledge
and uncertainty in multi-agent systems. The work uses tools from logic
(particularly modal logic and the idea of possible-worlds semantics),
probability theory, distributed systems, game theory, and AI, and I like
to think that it contributes to our understanding of each of these areas
as well.
Some themes of my current research include:
(1) applying ideas of decision theory to constructing algorithms in asynchronous
distributed systems, database systems, and wireless systems, (2) providing
foundations for useful qualitative notions of decision theory, (3) reasoning
about security.
Honors
Guggenheim Fellowship (for 2001-02).
Fulbright Fellowship (for 2001-02).
University Activities
Co-director: Cognitive Studies Program.
Chair, Admissions Committee, Department of Computer Science.
Professional Activities
Fellow, American Association of Artificial Intelligence.
Editor-in-chief: Journal of the ACM (as of May, 1997).
Consulting Editor: Chicago Journal of Computer Science.
Editorial board: Artificial Intelligence Journal; Information
and Computation; Journal of Logic and Computation.
Member: ACM Publications Board.
Chairman: ACM Preprint Repository.
Coordinator: CoRR (Computing Research Repository).
Member: LICS (IEEE Conference on Logic in Computer Science) Advisory Board.
President of Board of Directors: Corporation for Theoretical Aspects of
Reasoning About Knowledge.
Program Chair, 16th Annual IEEE Symposium on Logic in Computer Science
(2001).
Program Committee Member and Conference Chair, 8th Conference on Theoretical
Aspects of Rationality and
Knowledge (2001).
Lectures
A Computer Scientist Looks at Game Theory.
-. Invited talk, Games 2000, Bilbao, Spain (July, 2000).
-.Invited talk, 4th Conference on Logic and Foundations of Game and Decision
Theory, Torino, Italy (July,
2000).
Plausibility Measures and Default Reasoning. Amsterdam University (May,
2001).
Plausibility Measures: a General Approach for Representing Uncertainty
Northwestern University (May, 2001).
Complexity, Logic, and Computation: A Symposium in Honor of Albert Meyer,
Boston, MA (June, 2001).
Publications
"Axiomatizing Causal Reasoning." Journal of AI Research
12:317-337 (2000).
"A Note on Knowledge-based Programs and Specifications." Distributed
Computing 13(3):145-153 (2000).
"First-order Conditional Logic Revisited." ACM Transactions
on Computational Logic 1(2):175-207 (2000). With
N. Friedman and D. Koller.
"Multi-agent Only Knowing." Journal of Logic and Computation
11(1):41-70 (2001). With G. Lakemeyer.
"A Logic for SDSI's Linked Local Named Spaces." Journal of
Computer Security 9(1,2):47-74 (2001). With R.
van der Meyden.
"A Decision-theoretic Approach to Reliable Message Delivery. Distributed
Computing 14:1-16 (2001). With F.
Chu.
"A Decision-theoretic Approach to Resource Allocation in Wireless
Multimedia Networks." Proceedings of Dial
M for Mobility, 86-95 (2000). With Z. Haas,
L. Li, and S. B. Wicker.
"Conditional Plausibility Measures and Bayesian Networks." Proceedings
of the Sixteenth Conference on
Uncertainty in AI, 247-255 (2000).
"Minimum-energy Mobile Wireless Networks Revisited." Proceedings
of the IEEE Conference on
Communications (2001). With L. Li.
"A Logical Reconstruction of SPKI." Proceedings of the 14th
IEEE Computer Security Foundations Workshop
(2001). With R. van der Meyden.
"Review of 'Probability and Conditionals: Belief Revision and Rational
Decisions.'" Journal of Philosophical
Logic 100(2):277-281 (2000).
"The Unusual Effectiveness of Logic in Computer Science." Bulletin
of Symbolic Logic 7(2):213-236 (2001).
With R. Harper, N. Immerman, P. G. Kolaitis,
M. Y. Vardi, and V. Vianu.
"Editorial: An Author's Bill of Rights and Responsibilities."
Journal of the ACM 47(5):828-825 (2000).
"CoRR: A Computing Research Repository (with commentary)." ACM
Journal of Computer Documentation
24(2):41-48 (2000).
Landmark Publications
Reasoning About Knowledge. MIT Press (1995). With R. Fagin, Y.
Moses, and M. Y. Vardi.
"Knowledge and Common Knowledge in a Distributed Environment."
Journal of the ACM 37(3):549-587 (1990).
With Y. Moses. Awarded Godel Prize in 1997.
"Belief, Awareness, and Limited Reasoning." Artificial Intelligence
34:39-76 (1988). With R. Fagin. Conference
version winner of MIT Press Publisher's
Prize as best paper of the 9th International Joint Conference on
Artificial Intelligence (1985).
"An Analysis of First-order Logics of Probability." Artificial
Intelligence 46:311-350 (1990). Conference version
winner of Publisher's Prize as best paper
of the 11th International Joint Conference on Artificial Intelligence
(1989).
"Plausibility Measures and Default Reasoning." Proceedings of
the Thirteenth National Conference on Artificial
Intelligence, 1297-1304 (1996). To appear
in the Journal of the ACM . With N. Friedman. Commended for
its excellence by the Committee on the
"IGPL/FoLLI Prize for the Best Idea of the Year 1996."
Juris Hartmanis
Walter R. Read Professor of Engineering
Turing Award Winner
jh@cs.cornell.edu
Ph.D. California Institute of Technology, 1955
The strategic goal
of my research is to contribute to the development of a comprehensive
theory of computational complexity. Computational complexity, the study
of the quantitative laws that govern computation, is an essential part
of the science base needed to guide, harness, and exploit the explosively
growing computer technology. My current research interests focus on understanding
the computational complexity of chaotic systems and the classification
of undecidable problems in complexity theory.
Awards
Recipient of the Grand Medal of the Latvian Academy of Sciences (Lielo
Medalu) (2001).
Professional Activities
Member: National Academy of Engineering.
Foreign Member: Latvian Academy of Sciences.
Fellow: American Academy of Arts and Sciences; New York State Academy
of Sciences; AAAS.
Editor: Springer-Verlag Lecture Notes in Computer Science; Journal
of Computer and Systems Sciences; Fundamenta Informaticae.
Advisory Board: EATCS Monographs in Theoretical Computer Science; Springer-Verlag;
International Journal
of Foundations of Computing.
Member: DIMACS External Advisory Committee.
Member: Santa Fe Institute Science Board.
Member: Santa Fe Institute Science Steering Committee.
Member: University of Cincinnati Computing Program Review Committee (November
1-3, 2000).
University Activities
Chair: Engineering College Nominating Committee.
Member: FCI Founders Committee.
Lectures
Goedel, Undecidability and Automata Theory, Half Century of Automata Theory.
University of Western Ontario
(July 26, 2000).
Four lectures at Jyvaskyle University, Finland, (August 10-11, 2000).
-. Undecidability and Incompleteness Results in Theory of Computing
-. Succinctness and Minimality of Automata Description
-. Search for Limits of Feasible Computations
-. On the Complexity and Shape of Mathematical Proofs
Computational Complexity and Mathematical Proofs, University of Saarbruecken,
Germany (August 30, 2000).
What can Computational Complexity Theory Say about Mathematics?
-. Iowa State University (October 23, 2000).
-. Cray Lecture Series, University of Minnesota (October 30, 2000).
Publications
"Computational Complexity and Mathematical Proofs." Informatics-
10 Years Back, 10 Years Ahead.
Reinhard Wilhelm, editor. Springer-Verlag
LNCS 2000, 251-256 (2001).
Mark Heinrich
Assistant Professor
Member of the School of Electrical and Computer Engineering
and the Graduate Field of Computer Science
heinrich@csl.cornell.edu
http://www.csl.cornell.edu/~heinrich/
Ph.D. Stanford University, 1998
My research is concerned
with the design of active memory and I/O systems for next-generation servers
and data-intensive computing. This work has focused on extending the cache
coherence mechanism in modern servers to implement active memory operations-computation
performed in the memory system on behalf of the microprocessor to speed
up overall execution time. Coupled with this work is the exploration of
the effect of new networking technologies (i.e. InfiniBand) on next-generation
servers and the integration of active memory and I/O techniques with this
networking technology. We have also shown that active memory machines
and hardware cache-coherent distributed shared-memory (DSM) machines need
much the same support, and, in fact, that by building our single-node
active memory system we can also support a multiprocessor version of the
machine that we call active memory clusters. Active memory clusters can
achieve hardware DSM performance at the low cost of clusters.
In my work on Active I/O systems I am developing
a smart InfiniBand switch (which can also be used in active memory clusters)
that can support either normal or intelligent I/O devices, and offload
computation from the microprocessor to minimize latency and reduce bandwidth
requirements in the I/O system. This work also involves innovative operating
system restructuring, including the filesystem and the network stack.
The operating system in active I/O systems must be partitioned between
the microprocessor and the active I/O devices. Our own operating system,
SplitOS, is joint work between our research group and groups at Rutgers
and Princeton.
In work on scalable cache coherence protocols,
I am working on issues of fairness and robustness in scalable distributed
shared-memory (DSM) machines. In addition, I am looking at the quantitative
impact of many coherence protocol techniques by evaluating each technique
on a flexible DSM prototype. Together with Martin Burtscher, I am also
exploring predictive techniques in cache coherence protocols to minimize
latency.
Awards/Honors
Michael Tien '72 Excellence in Teaching Award (2000-2001).
IEEE Teacher of the Year Award (1999-2000).
NSF Faculty Early Career Development Award (2000-2004).
University Activities
Member: Intelligent Information Systems Institute; ECE Curriculum and
Standards Committee; ECE Long-
Range Recruiting Committee; ECE Experimental
Systems Recruiting Committee; ECE Circuits & MEMS
Recruiting Committee; CURIE Summer Program
for Women in Engineering; Fields of Electrical
Engineering, Computer Science.
Professional Activities
Publicity Chair: International Symposium on High-performance Computer
Architecture (PCA) (January, 2001).
Panelist: Mathematics, Information, and Computational Sciences Division
within the Office of Advanced
Scientific Computing Research in the Office
of Science at the U.S. Department of Energy (DOE) (April,
2001).
Program Committee: Workshop on Caching, Coherence, and Consistency (WC3),
held in conjunction with the
ACM Conference on Supercomputing (June,
2001).
Program Committee: International Conference on Parallel Architectures
and Compilation Techniques (PACT)
(September, 2001).
Lectures
Flash Forward: Better, Faster, Cooler. Cornell University Silicon Valley
Event, hosted by Hunter Rawlings, San
Mateo, CA (April, 2001).
Providing Hardware DSM Performance at Software DSM Cost. Seminar, University
of Rochester (April, 2001).
Hardware DSM Performance at Software DSM Cost. Air Force Research Laboratory,
Rome, NY (March, 2001).
A Case for Asynchronous Active Memories. ISCA Workshop on Solving the
Memory Wall (June, 2000).
Publications
"FLASH vs. (Simulated) FLASH: Closing the Simulation Loop."
In Proceedings of the 9th International
Conference on Architectural Support for
Programming Languages and Operating Systems (ASPLOS), 49-
58 (November, 2000). With J. Gibson, R.
Kunz, D. Ofelt, M. Horowitz, and J. Hennessy.
"Using Meta-level Compilation to Check FLASH Protocol Code."
In Proceedings of the 9th International
Conference on Architectural Support for
Programming Languages and Operating Systems (ASPLOS), 59-
70 (November, 2000). With A. Chou, B. Chelf,
and D. Engler.
"A Case for Asynchronous Active Memories." In Proceedings of
the ISCA Workshop on Solving the Memory
Wall (June, 2000). With R. Manohar.
Sheila Hemami
Associate Professor
Member of the School of Electrical and Computer Engineering
and the Graduate Field of Computer Science
hemami@cs.cornell.edu
http://www.ece.cornell.edu/people/faculty/faculty_list.shtml#shei
Ph.D. Stanford University, 1994
The emerging information
superhighway provides an example of the flexibility required of image
and video compression and transmission techniques. Varying network capacities,
differences in viewing devices, and a broad spectrum of user needs suggest
the desirability of coding techniques that can efficiently span large
quality and bandwidth ranges. Additionally, coded data must be robust
to errors and loss of varying degrees across multiple network segments.
For practicality, algorithms must be inexpensive to implement, in either
hardware or software. My research interests broadly concern such communication
of visual information. Particular topics of interest include multirate
video coding and transmission, compression specific to packet networks
and other lossy networks, and psychovisual considerations.
University Activities
College of Engineering Committee of Faculty Women.
Society of Women Engineers Faculty Advisor.
EE Curriculum and Standards Committee.
Peoplesoft Lab Oversight Committee.
EE General Recruiting Committee.
Summer presentation to students in "Inventing an Information Society"
(July, 2000).
Professional Activities
Reviewer, IEEE Trans. Signal Processing; IEEE Trans. Image Processing,
IEEE Trans. Circuits and Systems for Video Technology; IEEE Communications
Letters; IEEE ICIP 2001.
Associate Editor, IEEE Trans. Signal Processing.
Awards/Honors
HKN C. Holmes MacDonald Outstanding Teaching Award.
Michael Tien '72 Cornell College of Engineering Teaching Award.
Fulbright Distinguished Lecturer, State of Morocco (2001).
Publications
"Perceptual Quantization for Wavelet-based Image Coding." Proc.
IEEE Int. Conf. on Image Processing,
Vancouver, B.C. (September, 2000). With
M. G. Ramos.
"Subjective Quality Evaluation of Low Bit Rate Video." Proc.
Human Vision and Electronic Imaging 2001, San
Jose, CA (January, 2001). With M. A. Masry,
W. Osberger, and A. M. Rohaly.
"Generalized Rate-distortion Optimizations for Motion-compensated
Video Coding." IEEE Trans. Circuits &
Systems for Video Tech. (September, 2000).
With Yan Yang.
"Perceptually-based Robust Image Transmission over Wireless Channels."
Proc. IEEE Int. Conf. on Image
Processing, Vancouver, B.C. (September,
2000). With M. E. Buckley, M. G. Ramos, and S. B. Wicker.
"Robust Data Hiding using Psychovisual Thresholding." Proc.
IEEE Int. Conf. on Image Processing,
Vancouver, BC, Canada (September, 2000).
With M. A. Masry, and M. G. Ramos.
John Hopcroft
Joseph Silbert Dean of Engineering
Turing Award Winner
Professor
jeh17@cornell.edu
http://www.cs.cornell.edu/jeh
Ph.D. Stanford University, 1964
Since
January 1994, I have been the Joseph Silbert Dean of the College of Engineering.
Upon completion of my term as dean, which ends on June 30, 2001, I plan
to return to research in the Department of Computer Science at Cornell.
My research will center on the study of information capture and access.
I have also been involved in the theoretical aspects of computing, especially
analysis of algorithms, formal languages, automata theory, and graph algorithms.
I have coauthored four books on formal languages and algorithms with Jeffrey
D. Ullman and Alfred V. Aho.
I was formerly the associate dean for college
affairs and the Joseph C. Ford Professor of Computer Science. After receiving
an M.S. (1962) and Ph.D. (1964) in electrical engineering from Stanford
University, I spent three years on the faculty of Princeton University.
In 1967, I joined the Cornell faculty, was named professor in 1972 and
served as chairman of the Department of Computer Science from 1987 to
1992. I am an undergraduate alumnus of Seattle University, and was honored
with a Doctor of Humanities Degree, Honoris Causa, in 1990.
Professional Activities
National Academy of Engineering.
Scientific Advisory Committee for The David and Lucile Packard Foundation;
John Von Neumann Medal Selection Committee for the Institute of Electrical
and Electronics Engineers, Inc.
(IEEE);
School of Engineering Advisory Committee, Hong Kong University of Science
and Technology;
National Advisory Committee on Informatics Engineering, National College
of Industrial Relations (Ireland).
Fellow: American Academy of Arts and Sciences; American Academy for the
Advancement of Science; Institute of Electrical and Electronics Engineers
(IEEE); (Charter) ACM.
Associate Editor (and Editor): Journal of Computer and System Sciences.
Editor (and Member, Executive Committee): Algorithmica.
Associate Editor: Information Sciences.
Editor: International Journal of Computational Geometry and Applications.
Klara Kedem
Professor
kedem@cs.cornell.edu
http://www.cs.cornell.edu/kedem
Ph.D. Tel Aviv University, 1989
My
research area is Computational Geometry with applications to problems
in computer vision and bio-information. The attempt to deal with practical
problems (like shape comparison) by investigating their geometric nature,
yields a better theoretical understanding of the problems and provides
sound and efficient algorithms. Among the theoretical problems I work
on are problems in geometric optimization, such as covering a set of points
by a given number of shapes and facility location. I have investigated
the minimum Hausdorff distance as a tool for measuring shape resemblance
between images.
Many practical problems in the area of shape comparison
seek a fully automated solution. The robustness of the minimum Hausdorff
distance lends itself to such problems. In the last two years I have looked
into shape comparison problems in three dimensions. Such problems arise
in many life-science disciplines. In computational molecular biology I
have come up with a new metric, the URMS, to measure substructure resemblance
between proteins. This measure has been implemented and further applied
to the analysis of molecular dynamics. It proves superior to previously
used measures. With the department of life sciences at Ben Gurion University,
I have been looking at dendrite shape comparison and classification. Here
we applied a three dimensional Hausdorff distance for the problem and
are in the midst of devising new measures.
Professional Activities
Chair of the Computer Science Department, Ben-Gurion University of the
Negev, Israel.
Editorial board: Pattern Recognition Society Journal.
Guest editor of Computational Geometry: Theory and Applications.
Workshop program committee: Workshop on Algorithmic Engineering (WAE 01)
BRICS, University of Aarhus,
Denmark (August 28-31, 2001).
Reviewer: Israeli-U.S. Bi-national Science Foundation; The Academia -
Ministry of Science, Israel; Pattern Recognition Journal; International
Journal of Computational Geometry and Applications.
Grants:
LSRT Consortium, "Optimal Layout Design of Large Scale Satellite
Telephony Systems in Rural Regions"
(2000-2001).
Israeli Defense Ministry, "BGU Bioinformatics Center for the Interpretation
of the Human Genome" (2001-2002).
Publications
"Optimal Facility Location under Various Distance Functions."
Accepted for publication in International Journal
of Computational Geometry and Applications.
With S. Bespametnik, M. Segal and A. Tamir.
"Improved Algorithms for Placing Undesirable Facilities." Accepted
for publication in Computers and Operations Research. With M. J.
Katz, and M. Segal.
Jon Kleinberg
Associate Professor
kleinber@cs.cornell.edu
http://www.cs.cornell.edu/home/kleinber/
Ph.D. MIT, 1996
My research is concerned with algorithms that exploit
the combinatorial structure of networks and information.
The information we deal with is taking on
an increasingly networked structure; the World Wide Web serves as perhaps
the most compelling example of this phenomenon. One direction I have pursued,
motivated by this issue, is the development of algorithms that analyze
the link structure of the Web to identify high-quality information resources
- hubs and authorities relevant to broad topics. A second direction is
the development of graph models that can provide insight into the structure
of large networks. I have been studying an algorithmic framework in which
to frame questions about certain 'small-world' properties of networks;
and with Duncan Callaway, John Hopcroft, Mark Newman, and Steve Strogatz,
I have recently looked at models of random graphs that evolve over time.
A third line of research has been concerned with designing algorithms
that facilitate the rapid spread of information in a network; with David
Kempe and Al Demers, I have worked on the design of randomized 'gossip'
protocols that provide efficient, decentralized mechanisms for such tasks.
Discrete optimization provides a collection
of powerful techniques for approaching problems in this area; in particular,
balancing constraints imposed by many individuals leads to a range of
interesting new problems. With Christos Papadimitriou and Prabhakar Raghavan,
I have been studying an optimization-based framework for clustering and
data mining in which one has access to data from a large population; we
consider the extent to which designing effective algorithms can be balanced
with concerns about the privacy of each individual's data. With Amit Kumar,
I have been looking at resource allocation problems with multiple users;
since each user wants as much of the resource as possible, there are many
competing objectives, and it is natural to seek the 'fairest' solution.
Finally, many of the core problems in computational
biology require algorithms for analysis of large volumes of data; such
data is being generated at an accelerating pace by experimental studies
of genomes and proteins across a wide range of species. With Debra Goldberg,
Susan McCouch, and David Liben-Nowell, I have been investigating mathematical
and computational approaches to the analysis of evolutionary relationships
among species at the genomic level and the connection between this type
of analysis and the problem of comparative mapping. I have also developed
algorithms for relating sequence information to protein structure, and
with Ron Elber I am continuing to look at approaches to this issue based
on threading methods.
Awards
National Academy of Sciences Award for Initiatives in Research (2001).
David and Lucile Packard Foundation Fellowship (1999-2004).
ONR Young Investigator Award (1999-2002).
NSF Faculty Early Career Development Award(1997-2001).
Alfred P. Sloan Research Fellowship (1997-1999).
University Activities
Member: Cornell Faculty of Computing and Information (FCI) Founders.
Professional Activities
Member: National Academies Computer Science and Telecommunications Board
study on Fundamentals of
Computer Science.
Program Committees: IEEE Symposium on Foundations of Computer Science,
2001; International World Wide
Web Conference (2001); ACM International
Conference on Knowledge Discovery and Data Mining (2001); Workshop on
Algorithms and Data Structures (2001); Workshop on Randomization and Approximation
Techniques in Computer Science (2001).
Lecturer: Lipari Summer School on On-line Algorithms (2000).
NSF Review Panel member.
Lectures
Information Networks: Models and Algorithms.
-. America Online (December, 2000).
-. Packard Fellowship Annual Meeting (September, 2000).
-. Santa Fe Institute Workshop on Complex Interactive Networks (August,
2000).
Small-World Phenomena and the Dynamics of Information.
-. Workshop in Honor of Allan Borodin's 60th Birthday (June, 2001).
-. Snowbird Learning Workshop (April, 2001).
Structure and Content in World-Wide Web Search. Invited plenary lecture
at the Meeting of the North American Chapter of the Association for Computational
Linguistics (June, 2001).
Detecting a Network Failure. IEEE Symposium on Foundations of Computer
Science (November, 2000).
On-Line Algorithms for Routing and Search. Lipari Summer School (July,
2000).
Publications
"Spatial Gossip and Resource Location Protocols." Proc. 33rd
ACM Symposium on Theory of Computing
(2001). With D. Kempe and A. Demers.
"Provisioning a Virtual Private Network: A Network Design Problem
for Multicommodity Flow." Proc. 33rd ACM
Symposium on Theory of Computing (2001).With
A. Gupta, A. Kumar, R. Rastogi, and B. Yener.
"On the Value of Private Information." Proc. 8th Conf. on Theoretical
Aspects of Rationality and Knowledge
(2001). With C. Papadimitriou, and P. Raghavan.
"Adversarial Queuing Theory." Journal of the ACM 48(1):13-38
(2001). With A. Borodin, P. Raghavan, M.
Sudan, and D. Williamson.
"Universal-stability Results and Performance Bounds for Greedy Contention-resolution
Protocols." Journal of
the ACM 48(1):39-69 (2001). With
D. M. Andrews, B. Awerbuch, A. Fernandez, F. T. Leighton, and Z. Liu.
"Navigation in a Small World." Nature 406:845 (2000).
"Detecting a Network Failure." Proc. 41st IEEE Symposium on
Foundations of Computer Science, 231-239
(2000).
"Fairness Measures for Resource Allocation." Proc. 41st IEEE
Symposium on Foundations of Computer
Science, 75-85 (2000). With A. Kumar.
"Algorithms for Constructing Comparative Maps." Comparative
Genomics: Empirical and Analytical
Approaches to Gene Order Dynamics, Map
Alignment and the Evolution of Gene Families (David Sankoff
and Joseph H. Nadeau, editors), 243-261
(2000). With D. Goldberg and S. McCouch.
"The Syntenic Diameter of the Space of N-chromosome Genomes."
Comparative Genomics: Empirical and
Analytical Approaches to Gene Order Dynamics,
Map Alignment and the Evolution of Gene Families
(David Sankoff and Joseph H. Nadeau, editors),
185-198 (2000). With D. Liben-Nowell.
"Allocating Bandwidth for Bursty Connections." SIAM J. Computing
30(1):191-217 (2000). With Y. Rabani, and
E. Tardos.
"Node-disjoint Paths on the Mesh, and a New Trade-off in VLSI Layout."
SIAM J. Computing 29(4):1321-1333
(2000). With A. Aggarwal, and D. Williamson.
"Approximation Algorithms for Classification Problems with Pairwise
Relationships: Metric Labeling and
Markov Random Fields." Proc. 40th
IEEE Symposium on Foundations of Computer Science, 14-23 (1999).
With E. Tardos.
"Efficient Algorithms for Protein Sequence Design and the Analysis
of Certain Evolutionary Fitness
Landscapes." Journal of Computational
Biology 6(3-4):387-404 (1999).
"Authoritative Sources in a Hyperlinked Environment." Journal
of the ACM 46(5): 604-632 (September,1999).
Dexter Kozen
Joseph Newton Pew, Jr.
Professor of Engineering
kozen@cs.cornell.edu
http://www.cs.cornell.edu/kozen/
Ph.D. Cornell University, 1977
My research interests include the theory of computational
complexity, especially complexity of decision problems in logic and algebra,
program logic and semantics, and computational algebra. Recent work includes
new polynomial-time algorithms for type inference in type systems with
subtypes and recursive types; algorithms solving systems of set constraints
as used in program analysis; a unification algorithm for set constraints
and a new constraint logic programming language based on set constraints;
development of the theory of rational spaces and their relationship to
set constraints; an algorithm for decomposition of algebraic functions;
a new polynomial-time algorithm for resolution of singularities of plane
curves; efficient algorithms for optimal transmission of encoded video
data; optimality results for digital interleavers; and expressiveness,
complexity and completeness results for Kleene algebras with tests. Recently
I have begun to investigate algorithms for efficient code certification
and the application of Kleene algebra with tests to the verification of
compiler optimizations.
Honors
Class of 1960 Scholar, Williams College.
Stephen and Margery Russell Distinguished Teaching Award, College of Arts
and Sciences, Cornell.
University Activities
Member: Undergraduate Admissions Committee, College of Engineering; University
Arbitration Panel.
Faculty Advisor: Cornell Men's Rugby Football Club; Johnson Graduate School
of Management Rugby Football
Club; Cornell Women's Rugby Football Club.
Professional Activities
Program Committee Member: Foundations of Software Science and Computation
Structure; Mathematical
Foundations of Computer Science.
Editorial Board Member: Journal of Relational Methods in Computer Science;
Theory of Computing Systems.
Supervisory Board: Centre for Basic Research in Computer Science (BRICS),
Aarhus University; Goedel Prize
Committee.
Lectures
Language-based Security. Department of Computer Science, Dartmouth College,
Hanover, NH (March, 2000).
On the Completeness of Propositional Hoare Logic. RelMiCS 5 Conference,
Quebec City, Canada (January,
2000).
A Computer Scientist's View of Admissible Sets. Tarski Centenary Conference,
Warsaw, Poland (May, 2001).
Publications
"Certification of Compiler Optimizations using Kleene Algebra with
Tests." In Proc. 1st Int. Conf. Computational
Logic (CL2000), v. 1861 of Lecture Notes
in Artificial Intelligence, J. Lloyd, V. Dahl, U. Furbach, M. Kerber,
K.-K. Lau, C. Palamidessi, L. M. Pereira,
Y. Sagiv, and P. J. Stuckey, editors, London, Springer-Verlag,
568-582 (July 2000).
"On the Completeness of Propositional Hoare Logic." Proc. of
the 5th International Seminar Relational
Methods in Computer Science (RelMiCS 2000),
195-202 (January, 2000). With J. Tiuryn.
"On Hoare Logic and Kleene Algebra with Tests." Trans. Computational
Logic 1(1):60-76 (July, 2000).
"A Note on the Complexity of Propositional Hoare Logic." Trans.
Computational Logic 1(1):171-174 (July,
2000). With E. Cohen.
Dynamic Logic. MIT Press, Cambridge, MA (2000). With D. Harel and
J. Tiuryn.
"Myhill-Nerode Relations on Automatic Systems and the Completeness
of Kleene Algebra." In Proc. 18th
Symp. Theoretical Aspects of Computer Science,
A. Ferreira and H. Reichel, editors. Dresden, Germany
(February, 2001). Lecture Notes in Computer
Science, v. 2010, Springer-Verlag, 27-38.
"Intuitionistic Linear Logic and Partial Correctness." Proc.
16th Symp. Logic in Computer Science. IEEE
(June, 2001) With J. Tiuryn.
Dean Krafft
Senior Research Associate
Director of Computing Facilities
dean@cs.cornell.edu
http://www.cs.cornell.edu/home/dean
Ph.D. Cornell University, 1981
Iserve both as a researcher and an administrator
in the Department of Computer Science at Cornell. In my guise as an administrator,
I manage the Computing Facilities Support group and worry about a number
of issues including computer security, networking, and building web services.
Most recently, as part of the Nomad research project (http://www.nomad.cornell.edu),
I have been leading a campus-wide pilot of megabit-speed wireless LAN
technology. This will be rolled out by Cornell Information Technologies
as a Cornell campus service in the fall 2001.
On the research side, I am part of the Cornell
Digital Libraries Research Group (CDLRG - http://www.cs.cornell.edu/cdlrg).
A major focus of our effort is on interoperability issues for digital
libraries. As part of that broader thrust, I am a Co-principal Investigator
on the NSF-funded National Science Digital Library Project at Cornell
(http://www.SiteForScience.org).
My own particular interests focus on ensuring the availability in the
digital world of pre-digital published and manuscript materials, as well
as related issues on copyright, the public domain, and public access to
older and out-of-print materials.
Cristoph Kreitz
Senior Research Associate
kreitz@cs.cornell.edu
http://www.cs.cornell.edu/home/kreitz
Ph.D. FernUniversitaet Hagen, 1984
My primary research interest is the application of automated deduction
to the design, verification, and optimization of software systems. My
current research aims at developing a Logical Programming Environment
for the construction of reliable and efficient distributed systems. In
collaboration with the Nuprl and Ensemble research groups, I have built
semantics-based tools for the automatic optimization of protocol stacks
in the Ensemble group communication system. More recently, Robbert van
Renesse, Mark Bickford and I have developed a generic switching protocol
for the construction of adaptive systems and proved it correct with the
Nuprl proof development system. For this purpose, we introduced the concept
of meta-properties and used them to characterize communication properties
that can be preserved by switching. We also identified switching invariants
that an implementation of the switching protocol must satisfy in order
to work correctly. The verification efforts revealed a variety of implicit
assumptions that are usually made when designing communication systems
and uncovered minor design errors that would otherwise have made their
way into the implementation.
I am also interested in the development
of automatic proof procedures for classical and non-classical logics.
Together with former students from the Technical University of Darmstadt,
I work on proof search methods based on matrix-characterizations of logical
validity, a very compact representation of the search space. We have developed
a uniform proof search procedure for classical logic, intuitionistic logic,
various modal logics, fragments of linear logic, and for inductive specification
proofs. We have also developed a uniform algorithm for transforming the
machine-found matrix proofs into sequent proofs. In the past year, we
implemented JProver, a first-order intuitionistic theorem prover that
creates sequent-style proof objects, and connected it as external proof
engine to the interactive proof assistants Nuprl and MetaPRL. The combination
of these systems gives a user the full expressive power of the proof assistant
when dealing with complex proofs and verifications, while at the same
time taking advantage of well-understood and efficient proof techniques
for subproblems that only depend on first-order reasoning.
Professional Activities
Program Committee: IJCAR Workshop on Verification (2001).
Referee: Handbook of Automated Reasoning; Journal of Symbolic Computation;
Journal of Functional Programming.
Lectures
The NuPRL Open Logical Environment. Scottish Theorem Proving Meeting,
St. Andrews, Scotland (July,
2000).
Matrix-based Inductive Theorem Proving, International Conference TABLEAUX-2000,
St. Andrews, Scotland
(July, 2000).
Building Reliable, High-performance Communication Systems from Components.
Technical University of
Darmstadt, Germany (July, 2000).
A Logical Programming Environment for Communication Systems. University
of Potsdam, Germany
(December, 2000).
Protocol Optimization in Ensemble/Spinglass. DARPA FTN PI Meeting, St.
Petersburgh, (January, 2001).
Advances in Logical Programming Environments. DARPA PCES PI meeting, San
Diego (February, 2001).
An Open Logical Programming Environment,.DARPA PCES PI meeting, St. Louis
(May, 2001).
Formal Design of Reliable Software Systems. DARPA Information Survivability
Conference and Exposition II,
Anaheim (June, 2001).
Formal Design and Verification: Challenges and Prospects. Invited talk,
workshop on verification, International
Joint Conference on Automated Reasoning,
Siena, Italy (June, 2001).
Publications
"J. Prover: Integrating Connection-based Theorem Proving into Interactive
Proof Assistants." Proc. International
Joint Conference on Automated Reasoning,
LNAI, Springer (June 2001). With S. Schmitt, L. Lorigo, and A.
Nogin.
"An Experiment in Formal Design using Meta-properties." Proc.
DARPA Information Survivability Conference
and Exposition II (DISCEX 2001), IEEE Computer
Society Press (June 2001). With M. Bickford, R. van
Renesse, and R. Constable.
"Protocol Switching: Exploiting Meta-properties." Proc. International
Workshop on Applied Reliable Group
Communication (WARGC 2001), IEEE Computer
Society Press (April 2001). With X. Liu, R. van Renesse,
M. Bickford, and R. Constable.
"A Uniform Procedure for Converting Matrix Proofs into Sequent-style
Systems." Journal of Information and
Computation 162 (1-2):226-254 (2000).
With S. Schmitt.
"Matrix-based Inductive Theorem Proving." Proc. International
Conference TABLEAUX-2000, LNAI 1847,
Springer (July 2000). With B. Pientka.
Carl Lagoze
Digital Library Scientist
lagoze@cs.cornell.edu
http://www.cs.cornell.edu/lagoze/lagoze.html
MSE Wang Institute
Our group investigates the policies, organization, and architecture of
distributed information spaces. The Web, and the massive amount of content
that it makes available to us in our daily lives, provides the backdrop
for our work. The goal of our research is to understand and prototype
the services and organizational structures that we can build on top of
this global information base in order to increase its functionality, integrity,
and ease of use. We undertake this research with the recognition that
any proposed solutions must balance the economy and speed of automated
solutions against the often-irreplaceable expertise that comes from human
intervention.
Within this context we examine a number
of research areas: Architectures for storage of and access to the multiple
forms of digital content. Policies and enforcement mechanisms that facilitate
the preservation and secure management of distributed content. The role
of metadata, in its many forms, in the management of digital content.
Protocols for federating information across distributed repositories and
services. Architectures and services for interlinking amongst document
references and citations.
We
work in close collaboration with other researchers in the Cornell, national
and international library, computer science, and Internet communities.
Our research model is highly applied: building standards and systems and
supporting the deployment of them to our collaborators in the global information
community. This research model has produced Dienst, an architecture and
protocol for creating distributed document repositories and services,
the Open Archives Initiative Metadata Harvesting Protocol that provides
access to metadata in a variety of forms, and theFEDORA digital object
model for managing access to highly variable digital content.
Professional Activities
Member: Dublin Core Metadata Initiative Advisory Council; Executive Committee,
Open Archives initiative.
Program Committee: JCDL 2001; ECDL 2001; 10th International World Wide
Web Conference.
Lectures
Business Unusual: How Event-awareness May Breathe Life into the Catalog.
Bicentennial Conference on
Bibliographic Control in the New Millennium.
Library of Congress, Washington DC (November, 2000).
IFLA/DELOS/NSF Workshop: Standards and Metadata. EVA 2000 Moscow (November,
2000).
The Open Archives Initiative. Open Archives Initiative Open Days, Washington
DC (January, 2001) and Berlin
(February, 2001).
Metadata Musings. University of Virginia (April, 2001).
Publications
"The Open Archives Initiative: Building A Low-barrier Interoperability
Framework." Joint Conference on Digital
Libraries 2001, Roanoke, VA (September,
2001). With H. Van de Sompel.
"Combining RDF and XML Schemas to Enhance Interoperability Among
Metadata Application Profiles." In 10th
International World Wide Web Conference,
Hong Kong (May 2001). With J. Hunter.
"Keeping Dublin Core Simple: Cross-domain Discovery or Resource Description."
D-Lib Magazine (January,
2001).
"Business Unusual; How 'Event Awareness' May Breathe Life into the
Catalog." In Bicentennial Conference on
Bibliographic Control in the New Millennium,
Library of Congress, Washington DC (November, 2000).
"An Event-aware Model for Metadata Interoperability. In ECDL 2000,
Lisbon (September, 2000). With J. Hunter,
and D. Brickley.
"Policy-enforcing, Policy-carrying Digital Objects." In Fourth
European Conference on Research and Advanced
Technology for Digital Libraries, Lisbon
(September, 2000). With S. Payette.
Lillian Lee
Assistant Professor
llee@cs.cornell.edu
http://www.cs.cornell.edu/home/llee
Ph.D. Harvard University, 1997
The ultimate goal of natural language processing
is to enable computers to use human language as a communication medium
both robustly and gracefully. However, because of the subtleties of human
language, this goal cannot be achieved without access to large quantities
of high-quality linguistic and domain knowledge. A major focus of my research
is the development of "knowledge-lean" methods to overcome this
knowledge acquisition bottleneck: I am investigating techniques that allow
a system to automatically learn the requisite information directly from
text.
Recent work continues to explore the use
of distributional similarity as a powerful tool for bootstrapping the
knowledge acquisition process. The underlying idea is quite intuitive:
information about an object can be gleaned from the objects that are similar
to it, where similarity can be computed from unannotated data alone. But
there are a multitude of ways to implement this idea; we are currently
investigating different similarity-based paradigms, both theoretically
and through experiments on large datasets.
Also, work with Rie Kubota Ando has analyzed
Latent Semantic Indexing, a commonly-used and highly influential information
retrieval technique that seeks to uncover hidden document relationships
without engaging in standard natural language processing. We have shown
that the performance of this algorithm can be tied to the uniformity of
the underlying topic-document distribution, and we have provided a new
algorithm that automatically compensates for distributional non-uniformity.
Professional Activities
Program Chair: 2001 Conference on Empirical Methods in Natural Language
Processing (EMNLP).
Area Chair (Corpus-based Natural Language Processing): Thirty-ninth Annual
Meeting of the Association for
Computational Linguistics (ACL).
Workshops Chair: Second Conference of the North American Chapter of the
Association for Computational
Linguistics (NAACL).
Editorial Board: Computational Linguistics (2000-2002).
Editorial Board: Machine Learning (2001-2004).
Program Committee: Second Conference of the North American Chapter of
the Association for Computational
Linguistics (NAACL) (2001).
Program Committee: Third Conference on Recent Advances in Natural Language
Processing (RANLP) (2001).
Co-organizer: Text Learning: Beyond Supervision, a workshop at the Seventeenth
International Joint
Conference on Artificial Intelligence (IJCAI).
Invited Participant: Institute for Mathematics and its Applications (IMA)
Workshop on Mathematical
Foundations of Natural Language Modeling
(2000).
Member: NSF review panel.
Technical coordinator: joint study agreement between Cornell University
and IBM Watson on text mining and
document management, 1999-present.
Affiliated faculty: Intelligent Information Systems Institute.
Referee: ACM Transactions on Information Systems.
University Activities
Department of Computer Science liaison to the Department of Linguistics.
Member: Women in Science and Engineering Advisory Group.
Member: Women in Science and Engineering Term Chair Award committee.
Reader: Arts and Sciences Undergraduate Admissions.
Member: Field of cognitive studies.
Affiliated faculty: Cornell Information Science program.
Lectures
Distributional Similarity: Models and Methods. Carnegie Mellon University
(August, 2000).
Weakly-supervised Statistical Segmentation of Japanese. WhizBang! Labs
(August, 2000).
Natural Language Technology (three-hour tutorial). Rome Air Force Lab,
Knowledge Representation and
Reasoning series (October, 2000).
Applications of EM Techniques. Institute for Mathematics and its Applications
workshop on Mathematical
Foundations of Natural Language Modeling
(November, 2000).
On the Effectiveness of the Skew Divergence for Statistical Language Analysis.
Eighth Meeting of Artificial
Intelligence and Statistics (January, 2001).
Distributional Similarity and the Skew Divergence. Highland Technologies
(April, 2001).
The Iterative Residual Rescaling Algorithm: An Analysis and Generalization
of Latent Semantic Indexing.
-. University of Maryland (April, 2001).
-. Columbia University (May, 2001).
Publications
"Iterative Residual Rescaling: An Analysis and Generalization of
LSI." Proceedings24th Annual International
Conference on Research and Development
in Information Retrieval (SIGIR) (2001). With Rie Kubota Ando.
"On the Effectiveness of the Skew Divergence for Statistical Language
Analysis." Proceedings Artificial
Intelligence and Statistics (2001).
"Mostly-unsupervised Statistical Segmentation of Japanese: Applications
to Kanji." Proceedings First
Conference of the North American Chapter
of the Association for Computational Linguistics (NAACL)
(2000). With Rie Kubota Ando.
"Measures of Distributional Similarity." Proceedings 37th Annual
Meeting of the Association for Computational
Linguistics (ACL) (1999).
"Similarity-based Models of Word Co-occurrence Probabilities."
Machine Learning 34 (1999). With Ido Dagan,
and Fernando Pereira.
"Fast Context-free Parsing Requires Fast Boolean Matrix Multiplication."
Proceedings 35th Annual Meeting of
the Association for Computational Linguistics
and 8th Conference of the European Chapter of the
Association for Computational Linguistics
(ACL/EACL) (1997).
"Distributional Clustering of English Words." Proceedings 31st
Annual Meeting of the Association for
Computational Linguistics (ACL)(1993).
With Fernando Pereira and Naftali Tishby.
Yuying Li
Senior Research Associate
yuying@cs.cornell.edu
http://www.cs.cornell.edu/home/yuying.html
Ph.D. Waterloo University, 1988
My general research interests include numerical
optimization and scientific computation. In addition, I am interested
in the application of optimization methods to medical, engineering, and
financial problems.
My current interests focus on solving nonlinear constrained problems for
which the gradient computation is expensive and inexact. These problems
arise from many financial application problems.
Lectures
Lung Nodule Segmentation Using Optimization. The Workshop on Mathematics
in Image Processing 2000,
The University of Hong Kong (December 14-16,
2000).
Reconstructing the Unknown Local Volatility Function. A special session
of mathematics/optimization for
finance at Optimization 2001, Aveiro, Portugal
(July 23-25, 2001).
Publications
"A Trust Region and Affine Scaling Interior Point Method for Nonconvex
Minimization with Linear Inequality
Constraints." Mathematical Programming
Series A, 88(1):1-32 (2000).
Rajit Manohar
Assistant Professor
Member of the School of Electrical and Computer Engineering
and the Graduate Field of Computer Science
rajit@csl.cornell.edu
http://vlsi.cornell.edu/~rajit/
Ph.D. California Institute of Technology, 1998
My research is concerned with the design of efficient
asynchronous computation structures in VLSI and the use of formal methods
to guarantee the correctness of such structures.
In work on formal methods, I have developed
a new way to analyze the correctness of a class of program transformations
commonly used in asynchronous VLSI synthesis. The technique "decompiles"
the circuit into a higher level programming language, and provides high-level
information about the effect of applying the transformation.
The amount of power required by a processor
is quickly becoming a design constraint. In work on energy-efficient computation,
I have developed a new adaptive number representation that significantly
reduces the amount of energy required during instruction execution in
a general-purpose processor.
The presence of precise exceptions in a
processor can complicate its design. In work with Mika Nystrom and Alain
J. Martin, I developed a simple, distributed implementation of an algorithm
that implements precise exceptions in asynchronous processors, along with
a proof of its correctness using program transformations. An instance
of this mechanism was used in the design of an asynchronous MIPS processor.
Awards/Honors
Sonny Yau '72 Excellence in Teaching Award (2001).
IEEE Teacher of the Year Award (2001).
NSF Faculty Early Career Development Award (2000-2004).
Tau Beta Pi and Cornell Society of Engineers Excellence in Teaching Award
(2000).
University Activities
Member: Graduate Admissions Committee.
Member: Fields of Electrical Engineering; Computer Science; Applied Math.
Professional Activities
Program Committee : IEEE/ACM Symposium on Advanced Research in Asynchronous
Circuits and Systems
(March, 2001).
Workgroup Organizer: NSF Workshop on Neuromorphic Engineering (July, 2000).
Lectures
Width-adaptive Data Word Architectures. 2001 Conference on Advanced Research
in VLSI (March, 2001).
An Analysis of Reshuffled Handshaking Expansions. IEEE/ACM Symposium on
Asynchronous Circuits and
Systems (March, 2001).
Low Energy Adaptive Processors. Computer Science Colloquium, Cornell University,
Ithaca NY (October,
2000).
A Case for Asynchronous Computer Architecture. ISCA Workshop on Complexity-effective
Design (June,
2000).
Publications
"Width-adaptive Data Word Architectures." Proc. 19th Conference
on Advanced Research in VLSI,112-129
(2001).
"Precise Exceptions in Asynchronous Processors." Proc. 19th
Conference on Advanced Research in VLSI,16-
28 (2001). With Mika Nystrom, and Alain
J. Martin.
"An Analysis of Reshuffled Handshaking Expansions." Proc. 7th
IEEE/ACM Symposium on Asynchronous
Circuits and Systems, 96-105 (2001).
"A Case for Asynchronous Computer Architecture." Proc. ISCA
Workshop on Complexity-effective Design
(2000).
"A Case for Asynchronous Active Memories." Proc. ISCA Workshop
on Solving the Memory Wall (2000). With
Mark Heinrich.
Greg Morrisett
Associate Professor
jgm@cs.cornell.edu
http://www.cs.cornell.edu/home/jgm/
Ph.D. Carnegie Mellon University, 1995
My
research interests are in the design, semantics, and implementation of
programming languages. I am particularly interested in exploring how language
technology can be used to build reliable, secure, and high-performance
systems software. The unifying thread for all my research is the application
of advanced semantic constructs in real-world applications.
Recently, I have concentrated on type systems
and logics for enforcing security properties in low-level code. One byproduct
of this research is the design of a type system called TAL (Typed
Assembly Language) for the Intel x86 architecture and a suite of tools
that can efficiently type check binary code. The TAL type system is sufficiently
expressive that we can efficiently compile a variety of high-level safe
languages, such as ML, Scheme, Safe-C, and Java, to type-correct assembly
code. This technology provides a means to safely extend systems such as
kernels, web browsers, or hand-helds without the overheads of a virtual
machine or just-in-time compiler. Recent work on TAL includes extending
the type system to provide enforcement of other security policies, such
as resource constraints, that are outside the scope of traditional type
systems. I am also studying how other language technologies, such as binary
rewriting and inlined reference monitors, can be combined with types and
logics to support a wider class of important security properties.
Another interest is in language, compiler,
and runtime support for application-specific memory management. Though
standard garbage collection techniques provide a safe and convenient programming
model, many systems applications cannot tolerate the overheads introduced
by a general-purpose collector. My research here focuses on a range of
topics from fast conservative garbage collectors to advanced type systems
for region-based memory management, to generalizations of linear type
systems. The goal in all of this work is to provide the programmer with
more control over memory management without sacrificing safety.
My other recent interests are in run-time
code generation and modal type systems, efficient data representation,
and rich forms of polymorphism. Many of these issues are being explored
in the context of Cyclone, a next-generation systems language that is
being developed jointly between researchers at Cornell and AT&T Laboratories.
Awards
Allen Newell Medal for Research Excellence (2001).
Ralph Watts Excellence in Teaching Award (2001).
Presidential Early Career Award for Scientists and Engineers (2000).
NSF Faculty Early Career Development Award (1999).
Sloan Fellow (1998).
University Activities
Ph.D. admissions committee (1998-2000).
ECE hiring committee (2000).
Professional Activities
Editor: Journal of Functional Programming.
Associate Editor: ACM Transactions on Programming Languages and Systems.
Member: IFIP Working Group 2.8 on Functional Programming.
Participant: INFOSEC Research Council Study Group on Malicious Code; DARPA
ISAT Study on Mobile
Code.
Program Committee: Symposium on Principles of Programming Languages (PoPL
2001); International
Conference on Functional Programming (ICFP
2000); Principles and Practice of Declarative Programming
(PPDP 2000); International Symposium on
Memory Management (ISMM 2000); Principles of Programming
Languages (PoPL 2002); Workshop on Semantics,
Applications, and Implementation of Program
Generation (SAIG 2001); Workshop on Multi-language
Infrastructure and Interoperability (BABEL 2001).
Lectures
Language-based Security. Danish Technical Institute (ITU), Copenhagen,
Denmark (June, 2001).
Towards Next Generation Low-level Languages. University of Minnesota,
Minneapolis, MN, (April, 2001);
Harvard University, Cambridge, MA (February,
2001).
Next-generation Low-level Languages. Workshop on Semantics, Program Analysis,
and Computing Environments for Memory Management, London, England (January,
2001).
Mobile Code Security: An Overview. TARA Review, Air Force Research Laboratory
(March, 2000).
The Role of Type Systems in Mobile Code Security. DARPA ISAT Study Group
on Mobile Code (January,
2000).
Mobile Code Security. Air Force Scientific Advisory Board (December, 1999).
Advanced Type Systems for Low-level Languages. OpenSIG Conference (October,
1999).
Why Languages and Compilers Matter. INFOSEC Research Council Study Group
on Malicious Code (October,
1999).
Publications
"Syntactic Type Abstraction." Transactions on Programming Languages
and Systems 22(6)1037-1080
(November, 2000). With D. Grossman, and
S. Zdancewic.
"Attacking Malicious Code: A Report to the INFOSEC Research Council."
IEEE Software 17(5)
(September/October, 2000) With G. McGraw.
"Alias Types for Recursive Data Structures." In ACM Workshop
on Types in Compilation, Montreal, Canada
(September, 2000). With D. Walker.
"Scalable Certification for Typed Assembly Language." In ACM
Workshop on Types in Compilation, Montreal, Canada (September, 2000).
With D. Grossman.
"Typed Memory Management via Static Capabilities." Transactions
on Programming Languages and Systems
22(4):701-771 (July, 2000). With D. Walker,
and K. Crary.
"Alias Types." European Symposium on Programming, Berlin, Germany
(March, 2000). With F. Smith, and D.
Walker.
"Type Structure for Low-level Programming Languages." 1999 International
Colloquium on Automata,
Languages, and Programming . With K. Crary.
"From System F to Typed Assembly Language." ACM Transactions
on Programming Languages and Systems
21(3):528-569 (May 1999). With D.
Walker, K. Crary, and N. Glew.
"Principals in Programming Languages: A Syntactic Proof Technique."
In the 1999 International Conference on
Functional Programming, Paris, France,
197-207 (September, 1999). With S. Zdancewic, and D.
Grossman.
Andrew Myers
Assistant Professor
andru@cs.cornell.edu
http://www.cs.cornell.edu/andru
Ph.D. Massachusetts Institute of Technology, 1999
Semantic information about programs and data, obtained
from the programming language level, provides leverage for addressing
difficult problems in computer systems. Programming language ideas can
be applied effectively to problems in security, systems, and databases.
I am particularly interested in using language-level information to improve
security guarantees, performance, and transparency for distributed systems
and mobile code.
One example of this approach is our current
work on the problem of protecting confidential data. Current trends are
making this problem both more important and more difficult. Computer systems
are nearly completely connected via the Internet, allowing software to
disseminate private information to almost any location. In addition, we
increasingly use untrusted software; for example, downloaded software
such as applets. Standard access-control mechanisms are inadequate because
they do not control information propagation.
Static information control is a promising
approach for confidentiality. Our programming language Jif
judiciously extends Java with privacy annotations that facilitate
static analysis of information flows within programs. We are applying
the Jif programming model to distributed systems, in which not only programs
but also hosts may be untrusted. Computations spanning a network require
a protocol for the communicating hosts; we can show through static analysis
of such a distributed program when its protocol releases unintended information
to untrusted hosts participating in the computation. To develop a theory
for the security of such programs in the presence of downgrading channels,
we have introduced the idea of 'robust declassification,' which captures
the idea that untrusted hosts are unable to exploit these channels.
Professional Activities
Program Committee Member: 2001 IEEE Symposium on Security and Privacy;
18th ACM Symposium on
Operating Systems Principles (SOSP).
Lectures
Protecting Confidentiality Against Untrusted Programs and Hosts. Mini-Workshop
on Mobile Objects/Code and
Security, University of Tokyo, Japan (October,
2000).
Enforcing Confidentiality in Low-level Programs. SDI/LCS SeminarFest,
Carnegie Mellon University, Pittsburgh,
PA (June, 2001).
Publications
"Robust Declassification." Proceedings of the 14th IEEE Computer
Security Foundations Workshop, Cape
Breton, Nova Scotia, Canada (June, 2001).
With Steve Zdancewic.
"Secure Information Flow and CPS." Proceedings of the 10th European
Symposium on Programming, Genova,
Italy (April, 2001). With Steve Zdancewic.
Anil Nerode
Professor
Member of the Department of Mathematics
and the Graduate Field of Computer Science
anil@math.cornell.edu
www.math.cornell.edu/~anil/
Ph.D. University of Chicago, 1956
A decade in the works, the book Automata Theory
and its Applications, by Bakhadyr Khoussainov and myself, was published
in February, 2001 by Birkhauser (ISBN 0-8176-4027-2). This book makes
available in one place material that is used all the time for decidability
results in computer science. The basic theme is the correspondence between
classes of automata and languages for finite automata, Buchi Automata,
Rabin automata and the corresponding games and strategies for those games.
It is suitable for a one semester graduate course or a two-semester undergraduate
course. "Constructive Concurrent Dynamic Logic," with Duminda
Wijesekera, was finished this year and will appear in the Annals of
Pure and Applied Logic shortly. This was a project also of 10 years
duration, primarily because of the number of cases involved in the intuitionistic
treatment, which fortunately decreased from 120 to about 50, for the completeness
theorem.
My principal project is a research monograph with engineer Wolf Kohn on
the use of Finsler manifolds we associate with distributed optimal control
problems throughout engineering to extract close-to-optimal controls in
the form of finite automata. We dubbed this area Hybrid Systems in 1991,
and many now work in it.
Kohn and I founded a research and development company, Hynomics, some
years ago, with venture capital, in Seattle, and it is about to release
to a client a prototype 25,000 agent distributed system for supply chain
management, entirely based on new mathematical-computer science technology.
Publications
Foreword to: Principles of Modeling and Asynchronous Distributed Simulation
of Complex Systems by S.
Ghosh, IEEE Press (2000).
Keshav Pingali
Professor
pingali@cs.cornell.edu
http://www.cs.cornell.edu/Info/Projects/Bernoulli
Ph.D. Massachusetts Institute of Technology, 1986
My research group works on programming languages
and compiler technology for program understanding, restructuring, and
optimization. Our goal is to develop the algorithms and tools that are
required to raise the level of abstraction at which people program computers,
freeing them from having to worry about low-level details of machine architectures,
memory hierarchies, etc.
Our current focus is making programs adapt
to hardware faults. This problem has been studied by the operating systems
community, but proposed solutions such as message logging have a large
run-time overhead. We are developing program analysis and transformation
techniques to reduce this run-time overhead by exploiting information
about program behavior that can be deduced at compile-time. We plan to
deploy these techniques in the Adaptive Software Project, which is a multi-year,
multi-institutional project funded by the NSF as part of its Information
Technology Research (ITR) initiative.
We have continued our work on technology
for optimizing the performance of programs running on machines with deep
memory hierarchies. A recent break-through was the invention of fractal
symbolic analysis, which is a powerful program analysis technique that
permits compilers to restructure complicated programs far beyond the reach
of conventional compilers that use dependence analysis. Traditional symbolic
analysis is powerful but it is intractable for most programs. To circumvent
this problem, fractal symbolic analysis analyzes a program and its transformed
version by repeatedly simplifying these programs until symbolic analysis
becomes tractable, ensuring that equality of simplified programs is sufficient
to guarantee equality of the original programs. We have shown that this
approach is adequate for restructuring codes like LU factorization with
pivoting, which have not yielded to previous techniques in the literature.
The fractal approach to analysis is likely to prove useful for proving
other program properties.
We are continuing our work on next-generation
generic programming techniques. In our approach, algorithm implementors
use a different API than data structure designers, and the gap between
these APIs is bridged by a compiler. One view of this approach is that
it exploits restructuring compiler technology to perform a novel kind
of template instantiation. We are demonstrating the usefulness of this
new technology by deploying it in a system that generates efficient sparse
codes from high-level algorithms and specifications of sparse matrix formats.
These ongoing projects build on our earlier
work on restructuring compilation technology. Our group implemented one
of the first compilers that generated code for distributed memory machines,
starting from sequential shared memory programs. We introduced techniques
called runtime resolution and owner-computes rule, which have now become
standard in the area. Our work on linear loop transformations for enhancing
parallelism and locality has been incorporated by Hewlett-Packard into
its entire compiler product line. We also developed fast algorithms for
program analysis problems such as computing the control dependence relation,
the static single assignment form of a program, and dataflow analyses.
Many of these algorithms have been incorporated into commercial and research
compilers.
University Activities
Member: Cornell Theory Center Advisory Committee.
Professional Activities
Program Committee: ACM Symposium on Programming Languages Design and Implementation
(PLDI '01);
International Conference on Supercomputing
(ICS '01); EuroPar '01, Supercomputing 2001; HiPC 2001.
Consultant: Grammatech Inc.
Referee/Reviewer: ACM TOPLAS; IEEE Trans. Computers; Journal of Parallel
and Distributed Computing;
Journal of Supercomputing; IEEE Computer;
Software Practice and Experience;
Editorial Board: Int. Journal of Parallel Programming; and Discrete
Mathematics and Theoretical Computer
Science.
Lectures
Crash Recovery for Long-running Scientific Applications. IBM T. J. Watson
Research Center, Yorktown
Heights, NY (April, 2001).
Fractal Symbolic Analysis. Indian Institute of Technology, Kanpur (January,
2001).
Automatic Synthesis of Locality Enhancing Transformations for Imperfectly-nested
Loop Nests. IBM T.J.
Watson Research Center, Yorktown Heights,
NY (November, 2000).
Synchronization on Blue Gene. IBM T.J. Watson Research Center, Yorktown
Heights, NY (October, 2000).
Publications
"Tiling Imperfectly-nested Loop Nests." Supercomputing 2000.
With Nawaaz Ahmed, and Nikolay Mateev.
"Automatic Generation of Block-recursive Codes." EUROPAR 2000,
125-134. With N. Ahmed.
"Left-looking to Right-looking and Vice Versa: An Application of
Fractal Symbolic Analysis to Linear Algebra
Code Restructuring." EUROPAR 2000,
155-164. With N. Mateev, and V. Menon.
"A Framework for Sparse Matrix Code Synthesis from High-level Specifications."
Supercomputing 2000. With
Nawaaz Ahmed, Nikolay Mateev, and Paul
Stodghill.
"Landing CG on EARTH: A Case Study of Fine-grained Multithreading
on an Evolutionary Path." Super-
computing 2000. With Kevin B. Theobald,
Gagan Agrawal, Rishi Kumar, Gerd Heber, Guang R.Gao, and
Paul Stodghill.
Robbert van Renesse
Senior Research Associate
rvr@cs.cornell.edu
http://www.cs.cornell.edu/home/rvr/
Ph.D. Vrije University, Amsterdam, 1989
I am currently interested
in locating and aggregating data in a scalable manner. In the Astrolabe
system, we construct a hierarchical distributed database. Only the leaves
are writable. The internal nodes are generated at run-time using aggregation
dictated by SQL queries that are installed on-the-fly. All internal communication
is done using a peer-to-peer epidemic protocol. Astrolabe incorporates
an hierarchical public key infrastructure for security.
My other interests include applying formal
methods to systems problems and networking support for peer-to-peer applications.
Professional Activities
Vice-president, Research: Reliable Network Solutions, Inc.
Technical Consultant to FAST.
Publications
"Scalable Fault-tolerant Aggregation in Large Process Groups."
International Conference on Dependable
Systems and Networks, Goteborg, Sweden
(July, 2001). With Indranil Gupta, and Kenneth P. Birman.
"Spinglass, Scalable and Secure Communication Tools for Mission-critical
Computing." DARPA Information
Survivability Conference and Exposition
II (DISCEX 2001), IEEE Computer Society Press (June, 2001).
With Ken Birman and Werner Vogels.
"Protocol Switching: Exploiting Meta Properties." International
Workshop on Applied Reliable Group
Communication at the International Conference
on Distributed Computing Systems (ICDCS), Phoenix, AZ
(April, 2001). With Xioming Liu, Mark Bickford,
Cristoph Kreitz, and Robert Constable.
Mats Rooth
Professor
FCI, Joint with Linguistics
mr29@cornell.edu
Ph.D. University of Massachusetts, 1995
Over the past several
years, in collaboration with several colleagues, I have been developing
an approach to research and applications in linguistics and computational
linguistics that combines theoretical-linguistic formalisms, knowledge,
and problem statements with numerical modeling and parameter estimation
techniques. We have developed and implemented a grammatical formalism
known as head-lexicalized probabilistic context free grammar and have
employed it in large-scale experiments on German and English concerned
with learning lexical information from text corpora. The methods have
the status of a basic language technology, which can be applied in numerous
ways in research and applications. My own interests relate mainly to scientific
research in linguistics, particularly syntax, semantics and lexical semantics.
The work aims to devolop an experimental
paradigm for work in linguistics in which lingustic events are observed
in large text corpora using a robust parser and used to develop and test
theories. Linguistic theory is placed in contact with observations on
a massive scale using mixed numerical/symbolic comptutational models,
and much relevant knowledge is learned from data using numerical optimization
algorithms.
The linguistic representations assumed in this work are those of linguistic
theory, for instance grammars, labeled trees and structured lexical entries.
In the numerical modeling component, grammars and the lexicon are given
a probabilistic interpretation, as defining a parameterized family of
probability distributions. Many problems can then be solved using probabilistic
optimization algorithms. For instance, inducing a lexicon from a text
corpus amounts to maximizing a certain polynomial.
I also work on the semantics of human languages,
using logical and denotational-semantic techniques. Currently, I am investigating
connections between the syntax and semantics of elliptical constructions
and the semantics and phonology of intonation.
University Activities
Administration of Computational Linguistics Lab.
Graduate Admissions Committee.
Phonetics Search Committee.
Founders' Committee, Faculty of Computing and Information.
Social Sciences Advisory Council.
Professional Activities
2000 Workshop on Language Engineering, Johns Hopkins University. (Five-week
workshop in which a reading
comprehension prototype was implemented).
Editorial board: Natural Language Semantics.
Lectures
Parse Forest Computation of Expected Governors. Colloquium presentation,
University of Sussex (January,
2001).
Inducing a Semantically Annotated Lexicon. Symposium From Signals to Structured
Communication, Cornell
University (May 4 and 5, 2001).
Empty Domain Effects for Presuppositional and Non-presuppositional Determiners.
Conference on
Presupposition, Stuttgart (September, 2000).
Publications
"Parse Forest Computation of Expected Governors." Proceedings
of the 39th Annual Meeting of the
Association for Computational Linguistics
(2001). With Helmut Schmid.
"Inducing a Semantically Annotated Lexicon via EM-based Clustering."
Proceedings of the 37th Annual
Meeting of the Association for Computational
Linguistics (1999). With Stefan Riezler, Detlef Prescher,
Glenn Carroll, and Franz Beil.
"Inside-outside Estimation of a Lexicalized PCFG for German."
Proceedings of the 37th Annual Meeting of the
Association for Computational Linguistics
(1999). With Franz Beil, Glenn Carroll, Detlef Prescher, and
Stefan Riezler.
"Valence Induction with a Head-lexicalized PCFG." Proceedings
of the 3rd Conference on Empirical Methods
in Natural Language Processing (1998).
"On the Interface Principles for Intonational Focus." Proceedings
of the 6th Conference on Semantics and
Linguistic Theory (1996). With Glenn Carroll.
Fred B. Schneider
Professor
Director, Information Assurance Institute
fbs@cs.cornell.edu
http://www.cs.cornell.edu/People/fbs/
Ph.D. SUNY Stonybrook, 1978
Research this past
year continued into techniques to support the construction of concurrent
and distributed systems for high-integrity, mission-critical settings.
Security and fault-tolerance are of paramount concern here.
Inlined reference monitors (IRMs) remain
a promising approach for enforcing security policies, especially the fine-grained
policies needed when the Principle of Least Privilege is employed to protect
against hostile mobile code. This past year, we concentrated on putting
the approach into practice. Cornell's Digital Library Project is looking
to PSLang/PoET for imposing rights management and preservation policies
on digital objects in their repository; we have prototyped a "digital
university" to understand the enforcement issues there. And we started
investigating the deployment of IRMs in the Windows operating system.
Our investigations into interactions between
security and fault-tolerance (joint work with Lidong Zhou and Robbert
van Renesse) also continued. We have deployed COCA, our replicated certification
authority, to four sites on the Internet and made detailed performance
measurements. The system supports on-line revalidation of name-key bindings
and is designed to resist a broad collection of denial of service attacks.
University Activities
Sabbatical leave (2000-2001).
Founders Committee, Faculty of Computing and Information.
Engineering College Teaching Awards Committee.
Professional Activities
Director: AFRL/Cornell Information Assurance
Institute.
Editor: Distributed Computing; Information Processing Letters; High
Integrity Systems; Annals of Software Engineering; ACM Computing Surveys.
Co-managing Editor: Texts and Monographs in Computer Science, Springer-Verlag.
Chairman: International Review of UK Computer Science Research.
Program committee: NORDSEC 2000 Fifth Nordic Workshop on Secure IT Systems-Encouraging
Co
-operation; 3rd Information Survivability
Workshop (ISW-2000); Information/System Survivability Workshop
2001; 2001 Usenix Security Symposium; 2000
PODC Influential Paper Award.
Industrial Advisory Committees: JavaSoft Security Advisory Committee;
deCode Genetics Security Advisory
Board; Eweb University.Com Board of Advisors;
JXTA Technical Advisory Council; CIGITAL Technical
Advisory Board; Fast Search and Transfer
Technical Advisory Board.
Other Advisory Committees: MITRE Corporation, Research and Technology
committee of the Board of
Directors; UK Dependability Interdisciplinary
Research Collaboration (DIRC), Steering Committee.
IFIP Working Group 2.3 (Programming Methodology).
Honors
Fellow, American Association for Advancement of Science (1992).
Fellow, Association for Computing Machinary (1994).
Professor-at-large, University of Tromsoe, Tromsoe, Norway (1996-2004).
Daniel M. Lazar Excellence in Teaching Award (2000).
Lectures
The Case for Language Based Security. Invited Lecture. Informatics-10
Years Back, 10 Years Ahead.
Saarland University, Saarbruken, Germany
(August, 2000).
In-lined Reference Monitors. Microsoft Research. Redmond, Washington (October,
2000).
Radio Interview, "All Things Considered" (October 27, 2000).
The Case for Language Based Security. IFIP wg2.3. Santa Cruz,
CA (January, 2001).
The Design and Deployment of COCA. Distinguished lecture series. SUNY
Stony Brook. Stony Brook, NY
(February, 2001).
Fast P2P Possibilities. Tysil, Norway (February, 2001).
The Design and Deployment of COCA. Department of Computer Science. University
of Tromso. Tromso,
Norway (February, 2001).
The Case for Language Based Security. Keynote Address, ACM Southeast Conference
2001, Athens, GA
(March, 2001).
The Design and Deployment of COCA. Department of Computer Science. University
of Texas, Austin, TX
(March, 2001).
The Case for Language Based Security. IBM Corporation Hawthorne, NY (April,
2001).
The Design and Deployment of COCA. AFOSR Principal Investigators Meeting.
Ithaca, NY (May, 2001).
-. Information Assurance Institute Seminar
Series. AFRL/IF Rome Research Site, Rome, New York (June,
2001).
The Case for Language Based Security. AFCEA Conference. Hamilton, NY (June,
2001).
Escaping the Ivy Tower: Transitioning Technology from a University. AFCEA
Conference. Hamilton, NY (June,
2001).
Publications
"Enforceable Security Policies." ACM Transactions on Information
and System Security 3(1):30-50 (February,
2000).
"Formalizations of Substitutions of Equals for Equals." Millennial
Perspectives in Computer Science,
Proceedings of the 1999 Oxford-Microsoft
Symposium in honour of Professor Sir Antony Hoare, (Davies,
Roscoe, and Woodcock, editors) Palgrave
Publishers, Hampshire, England, 119-132 (November, 2000).
With David Gries.
"Editorial: Time for Change." Distributed Computing 13(4):187
(November, 2000).
"A Language-based Approach to Security. " Informatics- 10
Years Back, 10 Years Ahead. Lecture Notes in
Computer Science 2000 (Reinhard Wilhelm,
editor), Springer Verlag, Heidelberg, 86-101, (2000). And Greg
Morrisett, Robert Harper.
David Schwartz
Assistant Professor
dis@cs.cornell.edu
http://www.cs.cornell.edu/dis/
Ph.D. State University of New York at Buffalo, 1999
My main area of research is in computational mechanics. My recent work
focuses on applying mathematical techniques of deterministic uncertainty
to enhance methods of structural engineering analysis. I am applying one
such technique, called Interval Analysis, which adapts traditional numerical
operations by replacing numbers with intervals that model uncertain values.
This set-based form of structural analysis uses discrete mathematics to
perform types of parametric studies, that traditional techniques cannot.
However, the interval approach introduces numerical inaccuracies in solutions
that map to infeasible structural behaviors. A major goal of this research
involves improving the quality of the interval-based solutions to reduce
these inaccuracies to produce a technique suitable for design engineers.
This year I restructured the introductory
programming courses to update the technology and problem-solving tools
being taught. For the first time, students were introduced to Maple in
CS99, a preliminary course in programming that provides experience to
students before they take other courses. MATLAB has also received greater
focus in a new introductory programming course, CS100M. It has generated
quite a bit of excitement from students and other universities because
of the equal focus on both MATLAB and Java to help teach programming using
problems of computational science. I have also been coordinating the Computer
Science Department's "short courses," which are 1-credit courses
taught by Ph.D. students. These courses focus on teaching computer languages
and help the student instructors gain teaching experience. The instructors
turn to me for advice on curriculum development, teaching methods, and
navigating university policies. I have created a new short course, CS214:
Advanced UNIX Tools, which will be taught for the first time in the next
academic year.
Continuing my work from spring 2000, colleagues
in the College of Engineering and I converted the pilot CS100 Academic
Excellence Workshop (AEW) into a full-fledged program that runs in conjunction
with CS100M. We continued to pilot AEWs for CS100J, which is the more
traditional programming course. The AEW fosters cooperative learning,
where students work in teams to solve challenging problems in a non-competitive
environment. Students have responded enthusiastically, so we began designing
a new lab in spring 2001 to expand our capacity, especially to help the
CS100J pilot grow. Since AEWs tend to entice students, especially women
and minorities, we will be tracking engineering and computer science enrollments
in the next academic year to measure the effectiveness of our AEW program
in increasing diversity in the sciences. I look forward to working on
the CS AEW with Daisy Fan, whom I recruited into the department.
University Activities
Faculty Advisor: Association of Computer Science Undergraduates.
Coordinator: Academic Excellence Workshop (AEW) for CS100 program.
Coordinator: departmental short-course advice and instruction.
Member: Student Experience Committee.
Member: Computing Policy Committee.
Professional Activities
Textbook Reviewer: McGraw-Hill.
Lectures
The Inexperienced Educator's Guide To Managing A Large Hierarchical Staff.
Emerging Technologies for Industry and Education, Annual Meeting of the
St. Lawrence Section, American Society Engineering Education (March, 2001).
Bart Selman
Associate Professor
selman@cs.cornell.edu
http://www.cs.cornell.edu/home/selman
Ph.D. University of Toronto, 1991
The focus of my research
is on computation intensive methods in artificial intelligence, in particular
fast general reasoning, search, and planning techniques. I also investigate
the various sources of complexity in hard computational problems. In this
work, I explore connections between computer science, artificial intelligence,
and statistical physics. In addition, I study issues in problem representation,
including the robustness of encodings, abstraction, compilation, and approximation
methods. These issues are critical to the successful application of reasoning
and search methods in realistic domains. In terms of applications, I consider
challenge problems from planning, knowledge representation, multi-agent
systems, and machine learning. Our planning system, Black Box, developed
jointly with Henry Kautz of the University of Washington, is one of the
fastest general purpose planning systems. Finally, in recent projects,
I am exploring connections between machine learning methods and reasoning
and planning techniques. In joint work with groups at the University of
Washington and Microsoft Research, I study the use of Bayesian machine
learning techniques for dynamic adaptive control of computational resources.
Awards
Fellow: American Association for Artificial Intelligence.
Alfred P. Sloan Research Fellowship (1999-2001).
NSF Faculty Early Career Development Award (1998-2002).
University Activities
Chair: Bits On Our Minds Science Fair.
Coordinator of the AI Seminar Series.
Cognitive Studies Undergraduate Committee.
Member: Fields of Cognitive Studies and Applied Mathematics.
Professional Activities
Executive Council: American Association for Artificial Intelligence.
Editorial Board: Constraints: An International Journal; Annals of Mathematics;
and Artificial Intelligence.
Advisory Board: Journal of Artificial Intelligence Research (JAIR).
Guest Editor: Theoretical Computer Science; Discrete Applied Mathematics;
Electronic Notes in Discrete
Mathematics; and Annals of Mathematics
and Artificial Intelligence.
Organizer and program co-chair: SAT-2001: Workshop on Theory and Applications
of Satisfiability Testing.
Program committee: AAI-2000 Workshop on Leveraging Probability and Uncertainty
in Computation; 17th Intl.
Conf. on Artificial Intelligence (IJCAI-2001);
AAAI-2001 Symposium on Uncertainty in Computation.Referee/Reviewer: Artificial
Intelligence Journal (AIJ); JACM Constraints: An International Journal;
Journal of Artificial Intelligence Research (JAIR); NSF Journal of Automated
Reasoning; Theoretical Computer Science; Science.
Lectures
Insights from Statistical Physics into Computational Complexity. Colloquium,
California Institute of Technology
(Caltech), Pasadena, CA (October, 2000).
Survey of Artificial Intelligence and Knowledge Representation. Six lectures
at AFRL/IF, Rome, NY
(October/November, 2000).
Understanding Complexity: Recent Developments and Directions. Colloquium,
University of Minnesota,
Computer Science, Minneapolis, MN (October,
2000).
Principled Analysis and Synthesis of Agent Systems. Meeting on Taskable
Agent Software Kit, DARPA,
Charlotte, NC (October, 2000).
Challenge Problems for Propositional Reasoning and Search. Distinguished
Lecture Series, 7th Annual
Knowledge Representation and Reasoning
Lecture, York University, York, UK (November, 2000).
Understanding Complexity: Recent Developments and Directions. Colloquium,
Leeds University, Leeds, UK
(November, 2000).
Controlling Complexity: Structured Problems and Backbone Variables. Meeting
on Autonomous Negotiation
Teams, DARPA, Charlotte, NC (November,
2000).
Satisfiability Testing: Recent Developments and Challenge Problems Plenary
Lecture, AAAI Spring
Symposium on Answer Set Programming,
Palo Alto, CA (March, 2001).
Publications
"A Bayesian Approach to Tackling Hard Computational Problems."
Proc. 17th Conf. on Uncertainty and
Artificial Intelligence (UAI-2001), Seattle,
WA (2001). With E. Horvitz, Y. Ruan, C. Gomes, H. Kautz, and
M. Chickering.
"Balance and Filtering in Structured Satisfiable Problems."
Proc. 17th Intl. Conf. on Artificial Intelligence
( IJCAI-2001), Seattle, WA (2001). With
H. Kautz, Y. Ruan, D. Achlioptas, C. Gomes, and M. Stickel.
"Algorithm Portfolios." Artificial Intelligence Journal
126 (2001). With C. Gomes.
"Distribute Constraint Satisfaction in a Wireless Sensor Tracking
System." Proc. Workshop on Distributed
Constraint Reasoning (CONS-2), IJCAI-2001, Seattle (2001). With R. Bejar,
C. Gomes, and B. Krishnamachari.
"Analysis of Random Noise and Random Walk Algorithms." Principles
and Practice of Constraint Programming (CP 2000). Lecture Notes in
Computer Science 894:278-290 (2000). With B. Krishnamachari, Xi Xie, and
S. Wicker.
"Compute Intensive Methods in Artificial Intelligence." Annals
of Mathematics and Artificial Intelligence 28(1) (2000).
"Heavy-tailed Phenomena in Satisfiability and Constraint Satisfaction
Problems." Journal of Automated Reasoning 24(1/2):67-100 (2000).
With C. Gomes, N. Crato, and Henry Kautz.
David Shmoys
Professor and Member of the School of Operations Research
and the
Graduate Field of Computer Science
shmoys@cs.cornell.edu
http://www.cs.cornell.edu/home/shmoys/shmoys.html
Ph.D. University of California, Berkeley, 1984
The primary focus
of my research is on the design and analysis of efficient algorithms for
discrete optimization problems, and in particular, on approximation algorithms
for NP-hard problems.
Computational complexity theory provides
a mathematical foundation for the intractability of many computational
problems by proving that all NP-complete problems are equally hard. However,
in practice, real-world inputs for some NP-hard optimization problems
are straightforward to solve, whereas for others, even quite modestly
sized inputs are beyond the limits of the most sophisticated methods.
Analogously, from a theoretical perspective, for some NP-hard optimization
problems it is possible to efficiently compute solutions that are guaranteed
to be arbitrarily close to optimal, whereas for others, computing even
a crude approximation to the optimum is also NP-hard. In fact, the extent
to which such approximation algorithms exist for a problem provides a
surprisingly accurate theoretical yardstick for its actual computational
difficulty.
Our work has been motivated by the fact
that certain linear programming relaxations have been shown to provide
extremely good lower bounds on typical data. We provided a theoretical
understanding of the strength of these bounds by designing algorithms
that "round" the fractional solutions to these linear programs
to nearby integer solutions without degrading the quality of the solution
too much. We have been investigating a variety of clustering problems,
and in joint work with Moses Charikar, Sudipto Guha, and Eva Tardos, we
have obtained the first constant factor approximation algorithm for the
k-median problem. We have also obtained improved approximation algorithms
for the uncapacitated facility location problem (in joint work with Fabian
Chudak) and for a variety of more general multi-level facility location
problems (in joint work with Karen Aardal and F. Chudak, and with Nathan
Edwards). For the former problem, not only is the theoretical performance
of our algorithm surprisingly good, but it is more effective in practice
than all previously known heuristic procedures for this problem. We have
also been investigating the application of some of these rounding methods
to problems arising in computational genomics, in joint work with Dan
Brown and the group in plant sciences at Cornell, working under Steve
Tanksley. The resulting software for computing genetic linkage maps has
already seen widespread application within the genomics community.
University Activities
Member: Search Committee for Dean of the Graduate School.
Member: Genomics Task Force.
Member: FCI Working Group on Computational Biology.
Member: FCI Working Group on Computational Science.
Professional Activities
Editor-in-chief: SIAM Journal on Discrete Mathematics.
Editor: SIAM Journal on Computing.
Co-editor: SIAM/MPS Series on Optimization.
Associate Editor: Mathematics of Operations Research; Mathematical Programming;
Journal of Scheduling.
Guest Editor: J. `of Algorithms (Special issue devoted to selected papers
of the 11th Annual Symposium on Discrete Algorithms).
Lectures
Approximation Algorithms for Facility Location Problems.
-. Invited plenary lecture. CO 2000, Greenwich (July, 2000).
-. Invited plenary lecture. CONF 2000, Saarbrucken, Germany, September
2000.
A Constant-factor Approximation Algorithm for the K-median Problem. International
Symposium on Mathematical Programming, Atlanta, GA (August, 2000).
Selective Mapping: A Strategy for Optimizing the Construction of High-density
Linkage Maps.
-. Tri-Institutional Workshop on Computational Biology, Cornell ( September,
2000).
-. NIH Symposium - From Genes to Proteins and to Biological Function:
Computational Approaches, Cornell (October, 2000).
Publications
"Selective Mapping: A Strategy for Optimizing the Construction of
High-density Linkage Maps." Genetics 155:407-420
(2000). With T. J. Vision, D. G. Brown, R. T. Durrett, and S. D. Tanksley.
"Approximation Algorithms for Facility Location Problems." In:
Approximation Algorithms for Combinatorial Optimization, K. Jansen
and S. Khuller, editors, APPROX 2000, Lecture Notes in Computer Science
1913:27-33, Springer, Berlin (2000).
Landmark Publications
"Using Dual Approximation Algorithms for Scheduling Problems: Theoretical
and Practical Results." J. Assoc. Comput. Mach. 34:144-162
(1987). With D.S. Hochbaum.
"An Approximation Algorithm for the Generalized Assignment Problem."
Math. Programming 62:461-474 (1993). With E. Tardos.
"Approximation Algorithms for Fractional Packing and Covering Problems."
Math. Oper. Res. 20, 257-301 (1995). With S.A. Plotkin and E. Tardos.
"Scheduling to Minimize the Average Completion Time: On-line and
Off-line Approximation Algorithms." Math. Oper. Res. 22:513-544
(1997). With L. A. Hall, A. S. Schulz, and J. Wein.
"A Constant-factor Approximation Algorithm for the K-median Problem."
Proceedings of the 31st Annual ACM Symposium on Theory of Computing, 1-10
(1999). With M. Charikar, S. Guha, and E. Tardos.
E. Gun Sirer
Assistant Professor
egs@cornell.edu
http://www.cs.cornell.edu/People/egs/
Ph.D. University of Washington, 2001
I am broadly interested
in the design and implementation of distributed operating systems for
modern networks.
My main focus is on operating system support
for ad-hoc mobile networks. Ad-hoc networking is a newly emerging computing
paradigm where disparate, mobile hosts form temporary alliances to accomplish
certain tasks. They naturally arise in many real-world settings including
disaster relief operations, smart vehicles, and distributed sensor networks.
Such ad-hoc settings, characterized by constant change and limited resources,
require a high degree of adaptability and resource awareness from applications.
Current state of the art, however, requires all such functionality to
be manually encoded by the application programmer.
We are currently building an operating system,
called MagnetOS,
that provides automatic and transparent distribution of ad-hoc networking
applications. MagnetOS makes an entire ad-hoc network appear as a single
Java virtual machine to applications. By transparently migrating application
components from node to node, MagnetOS can increase system longevity,
reduce application delays, and decrease bandwidth consumption, even in
the presence of conflicting applications. Consequently, MagnetOS simplifies
application design, increases application portability by obviating error-prone
manual coding, and achieves an efficient placement of application components
within the network that adapt to changes in resource availability and
connectivity.
In conjunction with MagnetOS, we are examining
the design of secure, energy efficient operating systems for small, embedded
computers. Newly emerging smart cards, which are capable of downloading
and executing arbitrary code, are becoming part of our critical infrastructure
as they are being deployed in financial and telecommunications networks.
We are looking at different strategies for testing their security, as
well as evaluating code verification techniques for such severely resource-constrained
systems.
A third research direction looks at distributed
systems at the opposite end of the spectrum; namely, the high-performance
clusters that make up web sites. We are developing techniques for formally
specifying and reasoning about the interfaces they expose to the rest
of the network, as well as techniques for enforcing a security policy
uniformly across a web site.
Lectures
Distributed Virtual Machines: A New System Architecture for Networked
Computers (March-May, 2000).
A New System Architecture for Ubiquitous Computing. EGSA Graduate Engineering
Social Seminar Series (March, 2001).
Publications
"Comprehensive Synchronization Elimination for Java." Science
of Computer Programming, special issue on
Static Analysis (April, 2001). With Jonathan
Aldrich, Craig Chambers, and Susan Eggers.
"Design and Implementation of a Distributed Virtual Machine for Networked
Computers. Proceedings of the
Seventeenth Symposium on Operating Systems
Principles, 202-216, Kiawah Island, SC (December, 1999).
With Robert Grimm, Arthur J. Gregory, and Brian N. Bershad.
"Extensibility, Safety and Performance in the SPIN Operating System.
Proceedings of the Fifteenth
Symposium on Operating Systems Principles,
267-284, Copper Mountain, CO (December, 1995). With
Brian N. Bershad, Stefan Savage, Przemyslaw
Pardyak, Marc Fiuczynski, David Becker, Craig Chambers,
and Susan Eggers.
Evan Speight
Assistant Professor
Member of the School of Electrical and Computer Engineering
and the Graduate Field of Computer Science
espeight@csl.cornell.edu
http://www.ds-csl.cornell.edu/~espeight/
Ph.D. Rice University, 1998
My research centers around different aspects of distributed computing.
In particular, my three areas of focus are software runtime systems for
distributed computing platforms, improving the performance of commodity
cluster-based shared memory systems, and providing location-independent
data access through the concept of affinity directed mobility.
My work in software distributed system
runtime development has resulted in the dissemination of the Brazos system
to over 100 registered users worldwide. Brazos is a high performance parallel
programming environment distinguished by its use of multithreading, selective
multicast, a software-only implementation of scope consistency, and several
adaptive runtime performance tuning mechanisms. Brazos supports both shared
memory and message passing programming styles, and provides very efficient
mechanisms for thread migration and checkpoint/recovery. Currently, my
research on parallel programming runtime systems includes the development
a version of the Message Passing Interface (MPI) that provides thread
migration between nodes in a cluster for load balancing, fault tolerance,
and higher performance.
The emergence of ubiquitous communication
infrastructure and high performance, low power computing resources challenges
us to explore a better alternative to the current fragmentation of data,
applications, and devices that many users are faced with today. The Bifrost
location independent computing project seeks to provide a flexible and
comprehensive information access environment. The function of Bifrost
is to provide location and device independent access to data. Data in
Bifrost encompasses both information and the applications used to manipulate
that information. Bifrost uses affinity between data, and between users
and data, to make decisions about when and where to move data. We refer
to this approach as affinity directed mobility.
The core research issues of the project
are mobility management (how we move data and threads to support user
and device mobility), data management (how we represent, access, update,
and protect information), and application management (how we provide system-wide
access to application data). In contrast to previous approaches to mobile
data management that employ hoarding in anticipation of disconnection,
Bifrost anticipates "connection elsewhere" instead of disconnection.
Our rationale for this "almost always connected" approach is
as follows: We project that in 3-5 years, the situation will exist in
which users will be able to be in an "always connected" state,
connected almost anytime and anywhere that they choose. Wireless access
points (e.g., 802.11, infrared, and Bluetooth) will be common, even ubiquitous,
in nearly every home and public place, as they are today in many situations
including coffee shops, airports, and office buildings. Additionally,
services such as Infared and Bluetooth will allow connection to the Internet
in nearly any setting from almost anywhere. In this situation, the problem
of how a user can have unilateral access to any piece of remote personal
data, regardless of device or location, becomes increasingly important.
Thus Bifrost seeks to provide a common data access model, and exploring
the design space while providing a rich set of tools for the manipulation
and sharing of personal data is a core focus of the proposed research.
University or Professional
Activities
Member: ECE Curriculum and Standard Committee.
Member: Faculty Advisory Board on Information Technologies.
Reviewer: Transactions of Parallel and Distributed Computing.
Lectures
WSDLite: A Lightweight Alternative to Windows Sockets Direct Path. Fourth
Windows Symposium, Seattle, WA (August, 2000).
Efficient Parallel Computing on Multiprocessor Clusters. EE Colloquium,
Cornell University (March, 2000).
Publications
"WSDLite: A Lightweight Alternative to Windows Sockets Direct Path."
Proceedings of the 4th Usenix
Windows Symposium (August, 2000). With
John Bennett, and Hazim Abdel-Shafi.
"Efficient User-level Thread Migration and Checkpointing on Windows
NT Clusters." In Proceedings of the 3rd
Usenix Windows NT Symposium (July, 1999).
With Hazim Abdel-Shafi and John Bennett.
"Realizing the Performance Potential of the Virtual Interface Architecture."
Proceedings of the International
Conference on Super computing (ICS) (June,
1999). With John Bennett.
Paul Stodghill
Research Associate
stodghil@cs.cornell.edu
http://www.cs.cornell.edu/stodghil/
Ph.D. Cornell University, 1997
My research interest
is in program transformations and program synthesis for computational
science applications.
Increasingly, the frontiers of science are
being explored using computer simulation and modeling. Creating these
scientific applications poses a number of difficulties for computational
scientists. First, these applications are often very complex and may contain
hundreds of thousands, and even millions of lines of code. Furthermore,
these applications are intended to run on the most advanced, high performance
supercomputers. I am interested in developing software that helps to reduce
the development cost of these applications. One way to do this is to raise
the level of abstraction of programming languages and software libraries
in order to bring them closer to the programmer's natural domain of discourse.
In order to do this, specialized compilers and other program transformation
systems are required in order to transform these abstractions into efficient
executable programs.
An example of this is the work that I have
done on sparse compilers with Keshav Pingali and his students. Matrix
computations, such as those that perform linear algebra operations, are
very naturally expressed using Fortran or Matlab style loops and arrays.
However, many matrices that arise in scientific applications are sparse,
which means that they consist almost entirely (>99%) of zero values.
Modifying matrix algorithms to use special-purpose sparse matrix data
structures is a complicated and error-prone process. We have developed
software that allows the programmer to express their matrix computations
and sparse matrix data structures separately and in their most natural
representation. Then, we use program transformations to combine the algorithms
and data structures into a single, efficient executable.
Another area in which I am working is that
of fault-tolerance for scientific applications. Very few scientific applications
would be considered "mission-critical," but many do run for
very long periods of time (e.g., for weeks or months) or in environments
in which failures are likely to occur (e.g., the desktop workstations
within a department). We are currently investigating a number of different
approaches for providing fault-tolerance for scientific applications,
but one thing is already clear: different applications running on different
computers call for different fault-tolerance solutions. A programmer would
certainly like to have their application run in many different computing
environments, but interfacing with a number of fault-tolerant systems
is not usually realistic. In order to provide a single interface from
the programmer's point of view, we are investigating a number of implementation
techniques involving software library and program transformation technology.
This work is being done as part of a project on Adaptive Software with
researchers from other departments here at Cornell, Mississippi State
University, the College of William and Mary, and other institutions.
Apart from my core research agenda, I have
worked closely with computational scientists in order to develop novel,
high-performance, scientific applications. Apart from being interesting
in its own right, this work has given me insight into scientific programming
that I have found extremely valuable in my research on program transformations.
The most important project that I have been involved with was the Crack
Propagation for Teraflop Computers (CPTC) project, whose goal was to develop
fracture mechanics software that incorporated a number of recent advances
in numerical analysis and computational geometry and which delivered very
high performance on teraflop-scale computers. Other researches who worked
on this project include, Keshav Pingali, Steve Vavasis, Paul Chew, the
Cornell FractureGroup headed by Tony Ingraffea (Civil Engineering), Gao
Guong-Rong (ECE, University of Delaware) and Nikos Chrisochoides (CS,
College of William and Mary).
Lectures
Next-generation Generic Programming and its Application to Sparse Matrix
Computations. ACM International
Conference on Supercomputing, Sante Fe,
NM (May, 2000).
Parallel FEM Simulation of Crack Propagation on the AC3 Velocity Cluster.
ACM Second Workshop on
Cluster Cluster-Based Computing, Sante
Fe, NM (May, 2000).
Crack Propagation on Teraflop Computers. AC3 Meeting, Cornell University
(June, 2000).
Publications
"A Framework for Sparse Matrix Code Synthesis from High-level Specifications."
In Supercomputing 2000,
Dallas, TX (November 4-11, 2000). With
N. Ahmed, N. Mateev, and K. Pingali.
"Landing CG on EARTH: A Case Study of Fine-gained Multithreading
on an Evolutionary Path." In Supercomputing 2000, Dallas, TX (November
4-11, 2000). With K. Theobald, G. Agrawal, R. Kumar, G. Heber,
G. Gao, and K. Pingali.
"Next-generation Generic Programming and its Application to Sparse
Matrix Computations." In International
Conference on Supercomputing, 2000. With
N. Mateev, K. Pingali, and V. Kotlyar.
"Parallel FEM Simulation of Crack Propagation on the AC3 Velocity
Cluster." In The Second Workshop on
Cluster Cluster-Based Computing, 2000.
With G. Coulouris, G. Heber, D. Lifka, K. Pingali , D. Schneider,
P. Wawrzynek, and J. Zollweg.
"Parallel FEM Simulation of Crack Propagation - Challenges, Status,
and Perspectives." Irregular 2000. With
B. Carter, et al.
Eva Tardos
Professor
eva@cs.cornell.edu
http://www.cs.cornell.edu/home/eva/eva.html
Ph.D. Eotvos University, Hungary, 1984
My research interest
focuses on the design and analysis of efficient methods for combinatorial
optimization problems and their applications to various fields. I am mostly
working on problems that involve graphs or networks.
One general area of my research is designing
fast algorithms that provide provably close-to-optimal results for NP-hard
problems. Although research on polynomial time approximation algorithms
started in the1970s soon after the discovery of NP-completeness, it has
truly blossomed only in the past decade. Amazing progress has occurred
both in our ability to design approximation algorithms, and in proving
limits to approximability. Over the last years I have been working on
different approximation algorithms on various basic combinatorial problems.
I have worked on algorithms for various cut problems, and clustering type
problems. These problems are motivated by applications arising in vision,
networking and clustering.
I am also working on the interface of algorithms
and game theory. Approximation algorithms provide a tool for understanding
issues in game theory, such as evaluating and designing multi-agent games.
Such games underlie many phenomena in networking. In joint work with Tim
Roughgarden, I worked on understanding the quality of routing obtained
if separate agents each make selfish routing decisions in a global network.
Our goal is to understand the tradeoffs between introducing a global control
mechanism, and the loss in quality obtained by letting each agent make
selfish decisions. We use a model where each link in a network has a delay
that is an arbitrary monotone and continuous function of the amount of
flow on the link. We compare the quality of such a Nash equilibrium with
a globally planned optimal routing whose goal is to minimize the sum of
all delays. In the case of linear delay functions, we show that the global
optimum can be at most a factor of four-thirds better than the Nash equilibrium.
For more general delay functions, the value of the global optimum can
be arbitrarily better than the Nash equilibrium even when the delay functions
are rather simple. On the other hand, we show that for any monotone and
continuous delay function the cost of a Nash equilibrium is at most as
much as the optimal for the case in which each agent has to send twice
as much flow. Roughly speaking, this shows that one can eliminate the
need for introducing a global control mechanism at the cost of designing
a network that can support twice as much flow.
Awards
Fellow: American Academy of Arts and Sciences (2001).
Fellow: ACM (1998).
Faculty of the Year: Association of Computer Science Undergraduates.
University Activities
Director of Graduate Studies: Computer Science Department, Cornell University
Member: Fields of Operations Research and Applied Mathematics
Member: FACTA, Faculty Advisory Committee on Tenure and Appointment.
Member: WISE, Advisory group on Women in Science and Engineering.
Professional Activities
DIMACS External Advisory Board member, since 1996.
Co-organizer: DIMACS special year on Computational Intractability in1999-2001.
Area editor for Discrete Optimization: Mathematics of Operations Research.
Editor: SIAM Journal of Computer Science; Chicago Journal of Theoretical
Computer Science; Combinatorica; Journal of Interconnection Networks.
Program committee: International Workshop on Randomization and Approximation
Techniques in Computer
Science (APPROX), 2000; ACM-SIAM Symposium
on Discrete Algorithms (SODA) 2001; ACM
Symposium on the Theory of Computing (STOC)
2001.
Lectures
A Classification Problem Related to Multi-way Cuts. International Symposium
on Mathematical Programming,
Atlanta GA (August, 2000).
How Bad is Selfish Routing?
-. International Symposium on Mathematical Programming, Atlanta GA (August,
2000).
-. Cornell University, Department of Mathematics, VIGRE Interdisciplinary
Colloquium (September, 2001).
-. Cornell University, Computer Science Department, Distinguished Lecture
Series (October, 2000).
-. 41st Annual IEEE Symposium on the Foundations of Computer Science,
Redondo Beach, CA (November,
2000).
-. University of Southern California, Computer Science Department, Distinguished
Lecture Series (November, 2000).
Flow-based Algorithms for Some Metric Labeling Problems. International
Symposium on Mathematical
Programming, Atlanta GA (August, 2000).
A Constant-factor Approximation Algorithm for the K-median Problem. International
Symposium on
Mathematical Programming, Atlanta GA (August,
2000).
Classification with Pair-wise Relationships (invited talk). Horizons in
Combinatorics, A Conference on Graph
Theory, Vanderbilt, TN (May, 2001).
Sequence of four lectures on Approximation Algorithms. DONET summer school
on Integer and Combinatorial
Optimization, Utrecht, Netherlands (June,
2001).
Publications
"How Bad is Selfish Routing?" Proceedings of the 41st Annual
IEEE Symposium on the Foundations of
Computer Science (October, 2000). With
Tim Roughgarden.
"Allocating Bandwidth for Bursty Connection." SIAM Journal on
Computing 30(1):191-217 (February, 2001).
With Jon Kleinberg, and Yuval Rabani.
Landmark Publications
"Approximation Algorithms for Classification Problems with Pair-wise
Relationships: Metric Partitioning and
Markov Random Fields." In the Proceedings
of the 40th Annual IEEE Symposium on the Foundations of
Computer Science, 14-23 (November, 1999).
With Jon Kleinberg.
"A Constant-factor Approximation Algorithm for the K-median Problem.
In the Proceedings of the 31st Annual
ACM Symposium on the Theory of Computing,
1-10 (May, 1999). With Moses Charikar, Sudipto Guha,
and David Shmoys.
"The Quickest Transshipment Problem." Mathematics of Operations
Research 36-62 (February, 2000). With
Bruce Hoppe.
Fast Approximation Algorithms for Multicommodity Flow Problems. Journal
of Computer and System Sciences
50:228-243 (1995). With Tom Leighton, Fillia
Makedon, Serge Plotkin, Cliff Stein, and Spyros Tragoudas.
"A Strongly Polynomial Algorithm for the Minimum Cost Circulation
Problem." Combinatorica 5:247-255
(1985).
Tim Teitelbaum
Associate Professor
tt@cs.cornell.edu
http://www.cs.cornell.edu/Info/People/tt/Tim_Teitelbaum.html
Ph.D. Carnegie Mellon University, 1975
My research is concerned
with the use of fine-grain dependence graphs for specification, development,
and analysis of software and hardware systems. The objective is a new
generation of tools that provide precise and complete information about
the structure of complex systems. I am working to improve the performance
and functionality of generic dependence-graph technology, and I am also
exploring the use of the technology in various application domains.
Dependence-graph technology can be used
in a program understanding system, where the graphs may include forward
and backward links between each assignment statement and possible uses
of the values stored by that assignment. Pointer analysis can be used
so that indirect loads and stores through pointers are taken into account,
as well as indirect function calls. Dataflow analysis can be used so that
links between unrelated assignments and uses are excluded. Operations
that highlight forward and backward slices show the impact of a given
statement on the rest of the program (forward slicing) and the impact
of the rest of a program on a given statement (backward slicing). Operations
that highlight paths between nodes in the dependence graph (chops) show
ways in which the program points are interdependent (or independent).
Uses of slicing and chopping include software development, maintenance
and re-engineering of legacy code, test-data generation, security-assurance
and safety-assurance inspection, and semantic interference checking in
configuration management systems.
I am working with Ph.D. student Lyn Millett,
who is studying program dependence-graphs and slicing of concurrent programs.
[On leave spring
2001.]
Professional Activities
Co-founder and Chairman: GrammaTech, Inc.
Member: Science and Technology Study Group, Infosec Research Council (October
1999-May 2000).
Lectures
Static-semantic analysis based on dependence graphs. SPAWAR, San Diego,
CA (August, 1999).
-. Hewlett-Packard, Rancho Bernardo, CA (October, 1999).
Publications
"Issues in Slicing Promela and its Applications to Model Checking,
Protocol Understanding, and Simulation."
International Journal on Software Tools
for Technology Transfer 2(4):343-349 (2000). With L. Millett.
"Program Slicing of Hardware Description Languages." In 10th
IFIP WG10.5 Advanced Research Working
Conference on Correct Hardware Design and
Verification Methods (CHARM '99), Bad Herrenalb, Germany
(September, 1999). With E.M. Clarke, M.
Fujita, P.S. Rajan, T. Reps, and S. Shankar.
"A Case for Channel Analysis: Slicing Promela." Proceedings
of the International Symposium on Software
Engineering for Parallel and Distributed
Systems, Los Angeles, CA, 52-61 (May, 1999). With L. Millett.
Herbert Van de
Sompel
Assistant Professor
herbertv@cs.cornell.edu
http://www.cs.cornell.edu/people/herbertv/
Ph.D. Ghent University, 2000
During the academic year 2000/2001, I focused on furthering my work in
two areas of digital library research that I initiated in 1999: the Open
Archives Initiative and open reference linking (OpenURL).
With the Open Archives Initiative, important
progress was made through a generalization of the metadata harvesting
specifications that were released as the Santa Fe Convention in early
2000. Those specifications were only applicable to preprint-related metadata,
but nevertheless attracted the interest from communities outside of the
preprint realm. It was decided to revise the specification in depth, in
order to extend its applicability to metadata in general. The revision
process took 5 months. In that timeframe, a meeting was organized to discuss
issues involved in the generalization; several versions of a new protocol
document were compiled; an alpha-testing group consisting of 14 international
parties was assembled with the aim of testing and refining those versions.
In January 2001, the Metadata Harvesting Protocol of the Open Archives
Initiative was publicly released at a meeting in Washington DC. Carl Lagoze
(Cornell University CS) and I were appointed Executives of the Open Archives
Initiative, overseeing and coordinating the technical activities of the
Initiative. The Digital Library Federation and the Coalition for Networked
Information provide support for those activities. The Metadata Harvesting
protocol attracts broad international attention, and several funding agencies
explicitly or implicitly call for proposals that build on the protocol.
Important progress was also made in the
realm of the open reference-linking track of my work. With Patrick Hochstenbach
(Ghent University) and Oren Beit-Arie (Ex Libris USA), I had publicly
released a draft OpenURL specification in January 2000. The OpenURL specification
enables open reference linking by:
Allowing one to reference a scholarly object-as well as elements that
describe the context in which the reference is provided-in a consistent
way as name=value pairs on an HTTP GET or POST URL.
Allowing for the transfer of that reference-as well as of the contextual
elements-to a linking server.
In December 2001, I filed for standardization
of the OpenURL with NISO. Soon thereafter, the standardization request
was granted, and a formal standardization committee was formed. Meanwhile,
the draft OpenURL specification has already gained broad acceptance in
the scholarly information industry, with leading companies such as ISI,
EBSCO, Swets, SilverPlatter, etc. supporting it in their production systems.
Also, an important OpenURL-based prototype was set up with DOI/CrossRef
to demonstrate the feasibility of open reference linking based on DOIs.
Professional Activities
Member: Steering Committee, Open Archives Initiative.
Executive: Open Archives Initiative.
Technical Committee: Open Archives Initiative.
Research Advisory Board: OCLC.
NISO Committee AX (OpenURL standardization)
Co-organizer: Open Archives Initiative Meeting, Washington DC (January,
2001).
Workshop on the Open Archives Initiative and peer-review journals in Europe,
Geneva (March, 2001).
Lectures
Interconnecting Distributed Scholarly Information Resources in a Context
Sensitive Manner. Invited half-day
workshop, Access 2000 conference, St. John's,
Newfoundland, Canada (September, 2000).
The SFX Framework, the OpenURL and the Open Archives Initiative. Invited
presentation, SLA Global 2000
conference, Brighton UK (October, 2000).
Invited presentation in the session "Digital Libraries and their
Role in Knowledge Dissemination and Creation."
ASIS 2000 Conference, Chicago IL
(November, 2000).
Invited presentation in the session "Electronic Pre-print Initiatives:
A Discussion on Comparative, Historical and
Emerging Trends". At the ASIS 2000
Conference, Chicago IL (November, 2000).
The Roof is on Fire. Closing keynote at the fall 2000 meeting of the Coalition
for Networked Information. San
Antonio, TX (December, 2000).
The Open Archives Initiative. Keynote at the Workshop on the Open Archives
Initiative and peer-review journals
in Europe, Geneva (March, 2001).
The Open Archives Initiative and Scholarly Communication. Invited presentation,
IATUL Conference, Delft (May,
2001).
Publications
The Open Archives Protocol for Metadata Harvesting, Herbert Van
de Sompel and Carl Lagoze, editors
(January, 2001). http://www.openarchives.org/OAI/openarchivesprotocol.htm.
"The Open Archives Initiative: Building a Low-barrier Interoperability
Framework." JCDL2001 (2001). With C.
Lagoze. http://www.cs.cornell.edu/lagoze/papers/oai-jcdl.pdf.
"Open Linking in the Scholarly Information Environment using the
OpenURL Framework." D-Lib Magazine
7(3)(March, 2001). With Oren Beit-Arie.
http://www.dlib.org/dlib/march01/vandesompel/03vandesompel.htm.
"Generalizing the OpenURL Framework beyond References to Scholarly
Works." D-Lib Magazine
7(7/8)(July/August, 2001). With Oren Beit-Arie.
Charles Van Loan
Professor and Chair
Department of Computer Science
cv@cs.cornell.edu
http://ww.cs.cornell.edu/cv/
Ph.D. University of Michigan, Ann Arbor, 1973
I continue to work
in the computational multilinear algebra area. This includes factorization
approaches to various fast transforms, Kronecker product preconditioners,
and Kronecker-constrained least squares problems.
This past year Adam Florence and I perfected
our implementation of the fast Gauss transform (FGT) of Greengard and
Strain. We also developed effective methods for total least squares and
weighted least squares when the data matrix is a Kronecker product.
Applied Mathematics student Carla Martin
and I completed work on a solver for linear systems of the form (A-qI)x
= b where A is the product of upper triangular matrices. Our method is
an order of magnitude faster than the best of previous techniques.
University of Professional
Activities
Chair: Department of Computer Science.
Director of Undergraduate Studies: Department of Computer Science.
Member: FCI Founders.
Member: Core Curriculum Governing Board (Engineering).
Lectures
The Ubiquitous Kronecker Product. Invited Lecture, SIAM Linear Algebra
Meeting, Raleigh NC (October, 2000).
Publications
"The Ubiquitous Kronecker Product." Journal of Computational
and Applied Mathematics 123:85-100 (2000).
"GEMM-based Level 3 BLAS: Algorithms for the Model Implementations."
ACM Transactions on Mathematical
Software 24:268-302 (1999). With P.
Ling and B. Kagstrom.
Computational Frameworks for the Fast Fourier Transform, 273pp.,
SIAM Publications, Philadelphia, PA.
(1992).
Matrix Computations, 3d ed., 694pp, Johns Hopkins University Press,
Baltimore, MD (1996). With G.H. Golub.
Introduction to Scientific Computation: A Matrix-vector Approach Using
Matlab, 2d Ed., 365pp, Prentice-Hall,
Upper Saddle River, NJ (1999).
Steve Vavasis
Associate Professor
vavasis@cs.cornell.edu
http://www.cs.cornell.edu/home/vavasis
Ph.D. Stanford University, 1989
As computer hardware becomes more powerful, there is a corresponding growth
in the demand for more efficient algorithms to solve large-scale scientific
problems. My research is on the design and analysis of such algorithms.
Two Ph.D. students, V. Howle and G. Jonsson (both of the Center for Applied
Mathematics), completed their Ph.D.s working with me during the past year.
Howle's thesis was on algorithms for modeling and simulation of AC electric
power networks. Utility companies are interested in modeling the behavior
of the network in the presence of a fault (closed circuit breaker). The
governing equations, called the "swing equations," are nonlinear
differential algebraic equations for the rotor angles of the generators
in the system. We developed new, more accurate algorithms for the swing
equations by solving a linear algebraic subproblem (complex-weighted least
squares) more accurately. Work on geometry in scientific computing continues.
Jonsson's thesis considers the problem of robust intersection of parametric
patches with rays and planes. This problem arises in geometric modeling
and mesh generation. Our results show that the problem can be solved accurately
by transforming it to a generalized eigenvalue computation using the theory
of resultants and other algebraic techniques.
Four new students have begun to work with
me on other problems in scientific computing. We are looking at the following
topics: the effect of domain shape on solution to boundary value problems,
nonlinear diffusion equations, mesh generation for moving objects such
as a heart, and the protein model-fitting problem of x-ray crystallography.
University Activities
Member: Graduate admissions committee, Applied Mathematics.
Graduate admissions committee, Computer Science.
Faculty Senate.
University Hearing Board.
BOOM 2001 Vice-chair.
Professional Activities
Editorial Boards: Journal of Global Optimization; SIAM Journal Matrix
Analysis and Applications; SIAM
Review; Math. Program.
Vice-chair: SIAM Activity Group on Linear Algebra.
Referee: SIAM J. Optimization, SIAM J. Matrix An. App., Linear Alg.
App., Computational Geometry Theory and App.; Math. Progr.; International
Meshing Roundtable; J. Complexity.; NSF Panelist, Numeric,
Symbolic and Geometric Computing Program.
Lectures
Sparse Matrices and Automatic Differentiation in Semidefinite Programming,
International Conference on
Advances in Convex Analysis and Global
Optimization, Samos, Greece (June 6, 2000).
-. 17th International Symposium on Mathematical Programming, Atlanta,
GA (August 7, 2000).
Publications
"Quality Mesh Generation in Higher Dimensions." SIAM J. Comput.
29:1334-1370 (2000). With S. A. Mitchell.
"Accurate Solution of Weighted Least Squares by Iterative Methods."
SIAM J. Matrix An. App. 22:1153-1174
(2001). With E. Y. Bobrovnikova.
Werner Vogels
Research Associate
vogels@cs.cornell.edu
http://www.cs.cornell.edu/vogels
Ingenieur Hogere Informatica
Haagse Hogeschool, 1989
My research explores
the impact of scale on reliable distributed systems. The main focus is
on the development of new network protocols and middleware, as well as
on novel strategies to structure applications and support systems.
In the context of the Spinglass project, I am collaborating with Ken Birman
and Robbert van Renesse on the development of a new generation of high-scalable
reliable network protocols based on the principles of epidemic information
dissemination. Although the research has already resulted in protocols
for reliable multicast and group membership and failure detection, there
are still many open questions such as the application of epidemic techniques
to congestion control for many-to-many multicast protocols.
In the Galaxy project, the focus is on the distributed systems needs of
enterprise cluster computing systems. In particular, I investigate the
scalability problems that arise in these systems and try to provide solutions
in a form that is directly applicable to current practical problems. Currently
I am looking at the scalable cluster problems from three angles: foremost
I try to address cluster management scaling problems by developing a framework
for managing complete cluster farms with many different styles of cluster
computing present in the farm. Secondly, I am investigating some of the
issues that arise when providing support for the development of complex
cluster aware applications. Most recently, I have started to address some
of the more complex cluster system structuring issues such as meta-clusters
and geographical distributed clusters.
I also remain active in the field of high-performance cluster communication.
In the past, I collaborated with Thorsten von Eicken on building high-performance
user-level network interfaces, which eventually resulted in the VIA industry
standard for user-level network interfaces. More recently, I have started
investigating the usage patterns of VIA based devices in large-scale clusters,
especially with respect to hot-spot control and high-performance flow
control.
PROFESSIONAL ACTIVITIES
Steering Committee: Usenix Windows Systems Symposium.
Program Committee: Usenix 4th Windows Systems Symposium, IEEE International
Conference on Cluster Computing-Cluster 2000; 2001 IEEE Symposium on Applications
and the Internet; International SRDS Workshop on Dependable System Middleware
and Group Communication; Usenix 6th Conference on Object Oriented Tools
and Systems (Program Committee); IEEE 2nd Workshop on Internet Applications-WIAPP'01;
IFIP/ACM International Conference on Distributed Systems Platforms - Middleware
2001.
Program Chair: Distributed Systems Track of 2001IEEE Symposium on Applications
and the Internet.
General Chair: IEEE 2nd Workshop on Internet Applications-WIAPP'01.
LECTURES
Cluster Computing Made Easy: New Tools for Scalable Servers and Services."
Invited Lecture, Annual meeting of Advanced Cluster Computing Consortium
(June 2, 2000).
PUBLICATIONS
"Spinglass, Scalable and Secure Communication Tools for Mission-critical
Computing." Proceeedings of the 2001 DARPA Information Survivability
Conference and Exhibition - II (June, 2001). With K. Birman, and R. van
Renesse.
"Using Epidemic Techniques for Building Ultra-scalable Reliable Communication
Systems." Proceedings of the Large Scale Networking Workshop: Research
and Practice, Vienna, VA (March, 2001). With K. Birman and R. van Renesse.
"An Overview of the Galaxy Management Framework for Scalable Enterprise
Cluster Computing." Proceedings of the IEEE International Conference
on Cluster Computing: Cluster-2000, Chemnitz, Germany (December, 2000).
With D. Dumitriu.
"Tree-saturation in the AC3 Velocity Cluster Interconnect."
Proceedings of the 8th conference on Hot Interconnects, Stanford, CA (August,
2000). With D. Follett, J. Hsieh, D. Lifka, and D. Stern.
Golan Yona
Assistant Professor
golan@cs.cornell.edu
http://www.cs.cornell.edu/golan
Ph.D. Hebrew University, Jerusalem, 1999
My research focuses on computational molecular biology, with an emphasis
on developing tools and methodologies for large-scale analysis of protein
sequences and structures.
The goal of my research is to explore high-order
organization within the space of all proteins and obtain a global view
(a "road map") of the protein space. We hope that the global
view will yield valuable insights about the nature and function of new
genes and will lead to the discovery of high-level properties and principles
in the protein space.
This interdisciplinary research is rooted
in two different disciplines: computer science and molecular biology.
Being on the borderline between the two disciplines, this study is related
to fields of intensive research in both. It incorporates study and development
of methods for metric embedding, unsupervised learning techniques, efficient
graph algorithms and parallel applications, and efficient database management.
On the computational biology side, it is involved with development of
new algorithms and approaches for protein comparison, statistical models
of protein families and study of the mapping from sequences to structures.
A great emphasis is on developing novel machine-learning based techniques,
both in the context of the study of the protein space and as general-purpose
tools.
My study so far has resulted in two large
databases that are being used by biologists to study new genes: ProtoMap:
this database and its interactive web sites (http://protomap.cornell.edu
and http://protomap.stanford.edu)
are based on a graph-theoretic approach for the large-scale organization
of protein sequences. The site offers an automatic hierarchical classification
of all known protein sequences. It is a useful resource for the analysis
of known as well as new protein sequences and for the study of relationships
between protein families.
BioSpace: This database and its web sites
(http://biospace.cornell.edu
and http://biospace.stanford.edu)
are based on a new unified framework for sequence and structure analysis.
The result of this analysis is a preliminary global map of the protein
space. The sites also provide all-atom three-dimensional models for over
160,000 proteins.
Awards
Burroughs-Welcome Fellowship from the Program in Mathematics and Molecular
Biology (PMMB) (1998-
2000).
Noted for excellency in teaching, Faculty of Mathematics and Natural Sciences,
Hebrew University, Jerusalem,
Israel (1998 ).
Faculty of Mathematics and Natural Sciences Research award, Hebrew University,
Jerusalem, Israel (1998).
Jewish National KKL Foundation Research award (1996).
Intel-Dean Prize (1996).
Lectures
Towards a Complete Map of the Protein Space based on a Unified Sequence
and Structure Analysis of all
Known Proteins. NIH Symposium: From Genes
to Proteins to Biological Function, Ithaca, NY (October,
2000).
Towards a Complete Map of the Protein Space based on a Unified Sequence
and Structure Analysis of all
Known Proteins. The Eighth International
Conference on Intelligent Systems for Molecular Biology (ISMB),
San Diego, CA (August, 2000).
A Unified Sequence-structure Classification of Protein Sequences: Combining
Sequence and Structure in a
Map of the Protein Space. Fourth Annual
International Conference on Computational Molecular Biology
(RECOMB), Tokyo, Japan (April, 2000).
A Unified Sequence-structure Classification of Protein Sequences: Combining
Sequence and Structure in a
Map of the Protein Space. Quantitative
Challenges in the Post-genomic Sequence Era, San Diego, CA
(January, 2000).
Methodologies for Target Selection in Structural Genomics. Innovative
Computational Applications, San
Francisco, CA (October, 1999).
Modeling Protein Families using Probabilistic Suffix Trees. Third Annual
International Conference on
Computational Molecular Biology (RECOMB),
Lyon, France (April, 1999).
A Map of the Protein Space-An Automatic Hierarchical Classification of
all Known Proteins. The Sixth
International Conference on Intelligent
Systems for Molecular Biology (ISMB), Montreal, Canada
(June,1998).
Publications
"Within the Twilight Zone: A Sensitive Profile-profile Comparison
Tool based on Information Theory." Journal of
Molecular Biology (2001). With M. Levitt.
"Variations on Probabilistic Suffix Trees: Statistical Modeling and
Prediction of Protein Families.
Bioinformatics 17:23-43 (2001).
With G. Bejerano.
"Towards a Complete Map of the Protein Space based on a Unified Sequence
and Structure Analysis of All
Known Proteins. In the Proceedings of ISMB
2000, 395-406, AAAI Press. With M. Levitt.
"A New Nonparametric Pairwise Clustering Algorithm based on Iterative
Estimation of Distance Profiles.
Machine Learning (2001). With S.
Dubnov, R. El-Yaniv, Y. Gdalyahu, E. Schneidman, and N. Tishby.
"Methodologies for Target Selection in Structural Genomics. Progress
in Biophysical and Molecular Biology
73:297-320 (2000). With M. Linial.
"A Unified Sequence-structure Classification of Protein Sequences:
Combining Sequence and Structure in a
Map of the Protein Space. Proceedings of
RECOMB 2000, 308-317, ACM press. With M. Levitt.
"Comparison of Protein Sequences and Practical Database Searching.
In BioInformatics: Sequence, Structure,
and Databanks, edited by D. Higgins and
W. Taylor. Oxford University Press (2000). With S. Brenner.
Landmark Publications
"ProtoMap: Automatic Classification of Protein Sequences, a Hierarchy
of Protein Families, and Local Maps of
the Protein Space. Proteins: Structure,
Function and Genetics 37:360-378 (1999). With N. Linial, and M.
Linial.
"Global Self-organization of All Known Protein Sequences Reveals
Inherent Biological Signatures. Journal of
Molecular Biology 268:539-556 (1997).
With M. Linial, N, Linial, and N. Tishby.
Ramin Zabih
Associate professor
rdz@cornell.edu
http://www.cs.cornell.edu/rdz/
Ph.D. Stanford University, 1994
My research interests
lie in computer vision and in medical imaging. I have worked on a variety
of problems in early vision, including motion and stereo; many of these
problems can be solved very accurately using algorithms based on graph
cuts. In the last year I have been doing research on medical imaging in
the Radiology Department at Cornell Medical School, where I have focused
on improving the quality of MRIs. I have also investigated a number of
applications of computer vision, including new methods for content-based
access to databases of images, and have also developed some simple computer
vision techniques to automate program debugging at Microsoft.
Lectures
Fast Approximate Energy Minimization via Graph Cuts. University of Washington
CS Colloquium (January,
2001).
Publications
"Visual Correspondence with Occlusions via Graph Cuts." Proc.
International Conference on Computer Vision
(ICCV) (July, 2001). With Vladimir Kolmogorov.
"An Efficient Real-time Navigator Algorithm: Motion Organized Simultaneous
Acquisition with Interactive
Control (MOSAIC)." Proc. IEEE Conference
on Medical Imaging and Augmented Reality, Hong Kong
(June, 2001). With Vladimir Kolmogorov,
Yi Wang, Richard Watts, and Martin Prince.
"Exact Voxel Occupancy with Graph Cuts." Proc. IEEE Conference
on Computer Vision and Pattern
Recognition (CVPR) (2000). With Dan Snow,
and Paul Viola.
Landmark Publications
"Color-spatial Indexing and Applications." International
Journal of Computer Vision 35(3) (1999). With Jing
Huang, S. Ravi Kumar, Mandar Mitra, and
Wei-Jing Zhu.
"Fast Approximate Energy Minimization via Graph Cuts." Proc.
International Conference on Computer Vision
(ICCV) (1999). With Yuri Boykov, and Olga
Veksler.
"Markov Random Fields with Efficient Approximations." Proc.
IEEE Conference on Computer Vision and
Pattern Recognition (CVPR) (1998). With
Yuri Boykov, and Olga Veksler.
"A Variable Window Approach to Early Vision." IEEE Transactions
on Pattern Analysis and Machine
Intelligence 20(12) (1998). With Yuri Boykov,
and Olga Veksler.
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