CSP Seminar Abstracts

(see schedule for a list of talks)

 

Spring 2000

2:10-3:00, Thursdays

353 Durham

 

3/30/00

CSP Talk Canceled

Go to Distinguish Lecture

 

RICHARD M. KARP

 

THURSDAY - MARCH 30, 2000

Lecture:        2:00 p.m. - 3:00 p.m.

Reception:      3:00 p.m. - 4:00 p.m.

MOLECULAR BIOLOGY BLDG. ROOM 1414

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Sponsored by:  Cargill and Miller Lecture Funds

 

Abstract

 

A fundamental problem in molecular biology is to determine how genes and

proteins work in concert to control the functioning of living cells. This

talk will be a survey of algorithmic approaches to this problem, drawn from

the fields of combinatorial optimization, statistics, machine learning,

dynamical systems and stochastic simulation.

Proteins are the active elements that perform cellular functions. Proteins

are manufactured by transcribing genes into mRNA and then translating mRNA

into protein. The rates at which specific transcription and translation

processes take place depend on the environment of the cell and on the

abundances and spatial distribution of different species of mRNA and

protein. Thus the cell can be viewed as a complex feedback control system.

The DNA microarray is a recently developed tool capable of measuring the

transcription rates of thousands of genes in a single experiment. Technology

is being developed to measure large numbers of protein abundances in a

single experiment. Such high-throughput experimental tools will give a

panoramic view of the state of a tissue or collection of cells. By measuring

transcription one can distinguish normal tissue from neoplastic tissue, or

cells treated with a drug from untreated cells. By measuring the effects of

artificially inducing or inhibiting the transcription of particular genes

one can explore the structure of genetic regulation.

This talk will be concerned with the acquisition and interpretation of large

scale gene expression data. We will discuss algorithms for clustering or

classifying tissues on the basis of their gene expression patterns, as well

as algorithms to efficiently learn the structure of genetic regulatory

networks on the basis of judiciously chosen experiments.

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Richard M. Karp was born in Boston, Massachusetts in 1935 and was educated

at the Boston Latin School and Harvard University, where he received the

Ph.D. in Applied Mathematics in 1959. From 1959 to 1968 he was a member of

the Mathematical Sciences Department at the IBM Thomas J. Watson Research

Center. From 1968 to 1994 he was a Professor of Computer Science,

Mathematics and Operations Research at the University of California,

Berkeley. From 1988 to 1995 he was also associated with the International

Computer Science Institute (ICSI) in Berkeley. In 1995 he became a Professor

of Computer Science and Engineering and an Adjunct Professor of Molecular

Biotechnology at the University of Washington. This summer he will return to

Berkeley as a University Professor. His principal appointment will be in

Computer Science, and he will also hold appointments in Mathematics and

Bioengineering. In addition, he will again be a research scientist at ICSI.

The unifying theme in Karp's work has been the study of combinatorial

algorithms. His most significant work is the 1972 paper ``Reducibility Among

Combinatorial Problems,'' which shows that many of the most commonly studied

combinatorial problems are disguised versions of a single underlying

problem, and thus are all of essentially the same computational complexity.

Much of his subsequent work has concerned the development of parallel

algorithms, the probabilistic analysis of combinatorial optimization

problems, and the construction of randomized algorithms for combinatorial

problems. His current research is concerned with strategies for sequencing

the human genome, the physical mapping of large DNA molecules, the analysis

of gene expression data, and other combinatorial problems arising in

molecular biology.

Karp has received the U.S. National Medal of Science, the Harvey Prize

(Technion), the Turing Award (ACM), the Centennial Medal (Harvard

University) the Fulkerson Prize(AMS and Math. Programming Society), the von

Neumann Theory Prize(ORSA-TIMS), the Lanchester Prize (ORSA) the von Neumann

Lectureship (SIAM) and the Distinguished Teaching Award (Berkeley). He is a

member of the National Academy of Sciences, the National Academy of

Engineering and the American Philosophical Society, as well as a Fellow of

the American Academy of Arts and Sciences. He holds four honorary degrees.

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3/23

Intrusion Detection: An Audit Trial Method

Bin Shao

 

Abstract

 

As modern computer networks are vulnerable to malicious activities such as

unauthorized access to private data, denial of service, and unauthorized

intrusions, intrusion detection methods are becoming more important. There

are generally two branches in intrusion detection methods: recognize known

attacks and detect new intrusions. Knowledge bases are required to compare

the intrusion signatures with the stored patterns for the first method, in

order to adapt to new attacks, learning methods must be applied to update

the tendency and performance of the system. In this project, an neural

network is constructed as the system base architecture, an reinforcement

learning method is employed as training algorithm and a sliding window is

used to adapt to new changes. This system is currently being developed to

detect system performance anomalies.

 

 

3/2

A Hybrid Neural Network / Nearest Neighbor Modeling Approach

Craig Carmichael

 

Abstract

Artificial Neural Networks have been shown to be capable of modeling a large class of problems, usually resulting in good generalization. Nearest neighbor algorithms, however, still outperform ANNs on some modeling problems. Presented is an approach to combine the strengths of both methods into a single algorithm, called the neural neighbors algorithm (NNA). Preliminary work suggests that a hybrid approach can outperform either one in terms of generalization, on at least a subclass of problems. The NNA method is currently being developed to automatically find the optimal balance of the two approaches for any given data set. This should increase the scope of the method's usefulness across a wider range of modeling problems.

 

2/24

Dynammic Node Architecutre: An Information

Theoretic Approach

Varma Dantuluri

 

Abstract

 

Typically Artificial Neural Network training schemes require

network size to be set before learning is initiated. The learning

speed and generalization characteristics of ANNs are, however, dependent

on this pretraining selection of the network architecture. The training

and generalization viability of a specific network can, therefore, only

be evaluated posttraining. This work presents an Information Theoretic

method that alleviates this predicament by building the appropriate

network architecture dynamically during the training process. The

method, called Dynammic Node Architecture Learning (DNAL), eliminates

the need to select network size before training.

 

2/17

Modeling of Wideband CDMA Draft Specifications

Hemlata Ahir

 

Code Division Multiple Access (CDMA) is a technique in which the separation between users is acheived by orthogonality among the user codes. It involves spread spectrum modulation of the information signal resulting in a substantially increased bandwidth as compared to the information bandwidth itself. This basic principle with its numerous advantages has been adopted in CDMA systems such as IS-95 which has been accepted as a standard for second generation mobile systems. The keypoints of the IS-95 system will be discussed in this seminar. Also, a brief introduction to the third generation systems based on Wideband CDMA (WCDMA) will be provided followed by a discussion of modeling it based upon its draft specifications for the purposes of further research.

 

 

 

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Last updated March 30, 2000