Select a calendar:
Filter September Events by Event Type:
SUNMONTUEWEDTHUFRISAT
Conferences, Lectures, & Seminars
Events for September
-
Correlation Coefficients among Some Statistics Used for Signal Detection
Thu, Sep 07, 2006 @ 03:30 PM - 04:30 PM
Ming Hsieh Department of Electrical and Computer Engineering
Conferences, Lectures, & Seminars
SPEAKER: Prof. Jinsoo Bae, Sejong UniversityABSTRACT: In this talk, we address the derivation of joint distributions and correlation coefficients for seven pairs of statistics used commonly in a number of signal detection schemes. The upper and lower bounds of the correlation coefficients are obtained, and relationships among the correlation coefficients are derived. Explicit values of the correlation coefficients evaluated for some specific noise distributions are shown for easy reference.BIO: Jinsoo Bae graduated from Gyeong Gi High School of Science, Suwon, Korea, one year earlier than normal with an honor, in 1990. He received the B.S.E. (summa cum laude), M.S.E., and Ph.D. degrees in electrical engineering from Korea Advanced Institute of Science and Technology (KAIST) in 1993, 1995, and 1998, respectively. From January 1997 to December 1997, he was a Visiting Researcher with the Department of Electrical Engineering, the University of Tokyo, Tokyo, Japan. From January 1998 to February 2000, he was also with Accenture, Motorola Japan Ltd., and LG Telecom Ltd., before he joined the Department of Information and Communication Engineering, Sejong University, Seoul, Korea, in March 2000, where he is currently an Associate Professor. He has coauthored Advanced Theory of Signal Detection (Springer, 2002) and has published a number of papers on nonparametric signal detection. He is also a Senior Member of IEEE (Institute of Electrical and Electronics Engineers) and a Member of Korean Institute of Communication Sciences (KICS) and Institute of Electronics, Information, and Communication Engineers (IEICE). His research interests include signal detection theory and digital signal processing.HOST: Prof. Urbashi Mitra, ubli@usc.edu
Location: Hughes Aircraft Electrical Engineering Center (EEB) - -248
Audiences: Everyone Is Invited
Contact: Mayumi Thrasher
This event is open to all eligible individuals. USC Viterbi operates all of its activities consistent with the University's Notice of Non-Discrimination. Eligibility is not determined based on race, sex, ethnicity, sexual orientation, or any other prohibited factor. -
Some New Variance Reduction Ideas in Simulation
Tue, Sep 12, 2006 @ 03:30 PM - 04:30 PM
Ming Hsieh Department of Electrical and Computer Engineering
Conferences, Lectures, & Seminars
SPEAKER: Prof. Sheldon Ross, University of Southern CaliforniaABSTRACT: Building on the idea of stratified sampling we present an extension that is useful in analyzing simulation problems related to 1. systems having Poisson arrivals;2. monotone systems of Bernoulli data;3. systems of conditionally Poisson data;4. computing monotone functions of random numbersBIO: Sheldon M. Ross is a professor in the Department of Industrial Engineering and Operations Research at the University of
Southern California. He received his Ph.D. in statistics at Stanford University in 1968. He has published many technical
articles and textbooks in the areas of statistics and applied probability. Among his texts are A First Course in Probability,
Introduction to Probability Models, Stochastic Processes, and Introductory Statistics. Professor Ross is the founding and
continuing editor of the journal Probability in the Engineering and Informational Sciences. He is a Fellow of the Institute
of Mathematical Statistics, and a recipient of the Humboldt US Senior Scientist Award.
Author of: Statistical Aspects of Quality Control, Introduction to Stochastic Dynamic Programming, Probability Models for Computer Science, Introduction to Probability and Statistics for Engineers and Scientists,
Introduction to Probability Models,
Introductory Statistics,
Introduction to Probability Models, ISE, Simulation,
Introduction to Probability Models,
Student Solutions Manual for Introductory Statistics.Location: Hughes Aircraft Electrical Engineering Center (EEB) - 248
Audiences: Everyone Is Invited
Contact: Mayumi Thrasher
This event is open to all eligible individuals. USC Viterbi operates all of its activities consistent with the University's Notice of Non-Discrimination. Eligibility is not determined based on race, sex, ethnicity, sexual orientation, or any other prohibited factor. -
Reducing the Complexity of Graphical Models via Cycles
Tue, Sep 19, 2006 @ 03:30 PM - 04:30 PM
Ming Hsieh Department of Electrical and Computer Engineering
Conferences, Lectures, & Seminars
SPEAKER: Mr. Thomas R. Halford, Communication Sciences Institute, University of Southern CaliforniaABSTRACT: A decade ago, the introduction of turbo codes and iterative message passing algorithms revolutionized the theory and practice of coding. In the ensuing years, the coding theory community has become adept at designing codes from good graphical models - that is, models which imply low-complexity, near-optimal iterative message passing algorithms. Specifically, modern codes are constructed by connecting a large number of simple local codes together via a rich, random-like, cyclic interconnection network. A key observation from this work is that the introduction of cycles to graphical models can enable massive complexity reductions in model, and thus decoding, complexity.Whereas constructive graphical modeling problems (e.g. code design) have been widely addressed by the coding theory community, less is understood about the inverse problem of model extraction. Specifically, can good graphical models be obtained for existing algebraic codes, or more generally, for arbitrary systems? What tradeoffs exist between model complexity and cyclic topology for a given code? If good models can exist, how can they be obtained, or extracted? This talk presents a theoretical framework for the study of extractive graphical modeling problems. We first examine the limits of extraction by providing a characterization of the tradeoff between cyclic topology and complexity in graphical models for linear codes. Inasmuch as the cyclic topology of a graphical model is related to the performance of the decoding algorithms it implies, the bound presented in this talk provides insight into the limits of graphical model extraction. We then provide a formalization of extraction as optimization and describe some novel heuristics for both defining and solving this optimization problem. We conclude with a discussion of the importance of cyclic model extraction outside of coding.Bio: Thomas R. Halford received the B. A. Sc. degree in engineering physics from Simon Fraser University, Burnaby, B.C., Canada, in 2001. He is currently a doctoral candidate at the University of Southern California, Los Angeles, where his research focuses primarily on graphical models of codes. He spent the summer of 2005 visiting the Natural Language Processing Group at IBM T. J. Watson Research Center, Yorktown Heights, NY.Host: Prof. Keith M. Chugg, chugg@usc.edu
Location: Hughes Aircraft Electrical Engineering Center (EEB) - 248
Audiences: Everyone Is Invited
Contact: Mayumi Thrasher
This event is open to all eligible individuals. USC Viterbi operates all of its activities consistent with the University's Notice of Non-Discrimination. Eligibility is not determined based on race, sex, ethnicity, sexual orientation, or any other prohibited factor. -
Multiuser Detection in a Dynamic Environment
Wed, Sep 20, 2006 @ 10:30 AM - 11:30 AM
Ming Hsieh Department of Electrical and Computer Engineering
Conferences, Lectures, & Seminars
SPEAKER: Professor Ezio Biglieri, Universitat Pompeu Fabra, Barcelona, SpainABSTRACT: In mobile multiple-access communications, not only the location of active users, but also their number varies with time. In typical analyses, multiuser detection theory assumes that the number of active users is constant and known at the receiver, and coincides with the maximum number of users entitled to access the system. This assumption is often overly pessimistic, since many users might be inactive at any given time, and detection under the assumption of a number of users larger than the real one may impair performance. This talk describes a different, more general approach to the problem of identifying active users and estimating their parameters and data in a dynamic environment where users are continuously entering and leaving the system. The goal is to lay the foundation of multiuser detection theory in an environment where the number and the parameters of active users are unknown at the receiver, and in addition may change from one observation time to the next, following a known dynamic model. Using a mathematical tool known as Random Set Theory (which will be described), I shall show Bayesian-filter equations which describe the evolution with time of the a posteriori probability density of the unknown user parameters, and use this density to derive optimum detectors. Applications of the theory to the problem of neighbor discovery in wireless networks will also be briefly discussed.BIO: EZIO BIGLIERI received his training in Electrical Engineering from Politecnico di Torino (Italy), where he received his Dr. Engr. degree in 1967. He is presently with Universitat Pompeu Fabra, Barcelona, Spain; previously, he held professorships at Universita` di Napoli, Italy, Politecnico di Torino, Italy, and UCLA.In 1996--1997 he served as chairman of the IEEE Communications Society Awards Committee. In 1988, 1992, and 1996 he was elected to the Board of Governors of the IEEE Information Theory Society. In 1999 he was the President of the Society. He was the co-chairman of the IEEE 2000 International Symposium on Information Theory, Sorrento, Italy, and of ISITA 2004, Parma, Italy. He is a Distinguished Lecturer for the IEEE Information Theory Society and the IEEE Communications Society.From 1988 to 1991 he was an Editor of the IEEE Transactions on Communications, and from 1991 to 1994 an Associate Editor of the IEEE Transactions on Information Theory. From 1997 to 1999 he was an Editor of the IEEE Communications Letters, and its Editor-in-Chief from 2003 to 2005. From 1991 to 1997 he was an Editor of the European Transactions on Telecommunications, and its Editor in Chief from 1997 to 2001. Among other honors, in 2000 he received the IEEE Third-Millennium Medal, and the "IEEE Donald G. Fink Prize Paper Award." In 2001 he received the "IEEE Communications Society E. H. Armstrong Achievement Award." In 2004 he was presented the "Journal of Communications and Networks Best Paper Award."Host: Prof. Giuseppe Caire, caire@usc.edu
Location: Hedco Neurosciences Building (HNB) - 107
Audiences: Everyone Is Invited
Contact: Mayumi Thrasher
This event is open to all eligible individuals. USC Viterbi operates all of its activities consistent with the University's Notice of Non-Discrimination. Eligibility is not determined based on race, sex, ethnicity, sexual orientation, or any other prohibited factor. -
The Physical View of Computational Complexity
Fri, Sep 22, 2006 @ 11:00 AM - 12:00 PM
Ming Hsieh Department of Electrical and Computer Engineering
Conferences, Lectures, & Seminars
Dr. Allon Percus
Division of Computer, Computational and Statistical Sciences, LANL / Department of Mathematics, UCLAPhysicists define a phase transition as an abrupt change in microscopic order, such as the transition from a solid to a liquid. Many fundamental problems in computer science exhibit phase transitions as well. The classic example is satisfiability: given a set of logical constraints acting on Boolean variables, can one assign truth values to the variables so that all constraints are simultaneously satisfied? For randomly generated formulas with many variables, as one increases the number of constraints per variable, there is a threshold at which the answer goes abruptly from almost certainly yes to almost certainly no. Moreover, this phase transition is connected with algorithmic performance. Over a wide range of computational problems, the hardest instances to solve are those near the transition. I will discuss the role of phase transitions in random combinatorial problems,demonstrating how the physical view of the phase structure has transformed our understanding of average-case computational complexity and inspired new algorithmic approaches.Location: Hughes Aircraft Electrical Engineering Center (EEB) - 248
Audiences: Everyone Is Invited
Contact: Shane Goodoff
This event is open to all eligible individuals. USC Viterbi operates all of its activities consistent with the University's Notice of Non-Discrimination. Eligibility is not determined based on race, sex, ethnicity, sexual orientation, or any other prohibited factor. -
Finite-Length Optimization of Iterative Coding Systems Via Scaling
Fri, Sep 22, 2006 @ 11:00 AM - 12:00 PM
Ming Hsieh Department of Electrical and Computer Engineering
Conferences, Lectures, & Seminars
SPEAKER: Prof. Ruediger Urbanke, Swiss Federal Institute of TechnologyABSTRACT: The infinite-length performance of iterative coding systems is by now relatively well understood. Much less is known about the practical important case of finite-length codes. I will argue that a method called "finite-length scaling", which is based on relating the code performance of various lengths, is a useful tool for the analysis and optimization of real systems. This method has the advantage that it is in principle applicable in a fairly general setting.So far, however, the method has been worked out explicitly only for the case of transmission over the binary erasure channel and we are just about to understand the case of transmission over the binary symmetric channel under Gallager A decoding.I will describe what remains to be done and what we can expect to see as final result.[This is joint work with Abdelaziz Amraoui, Jeremie Ezri, and Andrea Montanari.]Bio: Ruediger L. Urbanke received his Diplomingenieur from the Vienna Institute of Technology in 1990 and his M.S. and Ph.D. in Electrical Engineering from Washington University in 1992 and 1995, respectively. From 1995-1999 he held a position at the Mathematics of Communications Department at Bell Labs. Since November 1999, he has been on the Faculty of the Swiss Federal Institute of Technology in Lausanne. He is a recipient of a Fulbright Scholarship and a co-recipient of the IEEE Transactions on Information Theory 2002 Best Paper Award. Since October 2000 he has been an Associate Editor of the IEEE Transactions on Information Theory.Host: Prof. Giuseppe Caire, caire@usc.edu
Location: Vivian Hall of Engineering (VHE) - 217
Audiences: Everyone Is Invited
Contact: Mayumi Thrasher
This event is open to all eligible individuals. USC Viterbi operates all of its activities consistent with the University's Notice of Non-Discrimination. Eligibility is not determined based on race, sex, ethnicity, sexual orientation, or any other prohibited factor. -
Chem-Bio Informatics Approaches to Drug Design by Dr. Rajni Garg
Fri, Sep 22, 2006 @ 01:00 PM - 02:00 PM
Ming Hsieh Department of Electrical and Computer Engineering
Conferences, Lectures, & Seminars
Computer assisted drug design techniques play a major role in lead optimization in drug discovery and development, which significantly reduces the time and cost. Chem.-bio informatics encompasses the design, organization, storage, management, retrieval, analysis, dissemination, visualization and use of chemical and biological information. Various tasks involved are data mining, molecular modeling (docking), defining quantitative structure-activity relationships (QSAR), pharmacophore mapping, structure/substructure searching etc. for predicting biological activity and other properties from chemical structure. Lately, many engineering approaches such as data mining, neural networks, pattern recognition, shape analysis and 3D graphics are being increasingly applied for multi-modality data analysis in order to understand the drug-receptor interaction. In the first part of the talk an introduction of QSAR, neural network, pharmacophore mapping and some of the molecular modeling techniques will be presented. The second half will focus on role of some of the emerging approaches in chem.-bio informatics and a few selected applications in HIV drug design and environmental toxicity will be presented.Bio:
Dr. Rajni Garg received the Ph.D. degree from Birla Institute of Technology and Science (BITS), Pilani, India in 1996. She joined Professor Corwin Hansch’s laboratory for her postdoctoral research in 1997. She is now a Research Professor in Chemistry and Bimolecular Science Department at Clarkson University, NY; and chemistry and Biochemistry Department at Cal State, San Marcos, CA. Her research interests are in the areas of computer-aided drug design, database development, data mining, chembioinformatics, and environmental toxicity prediction. Dr. Garg is a member of ACS, ISCB, AAAS and many other Societies. She received ACS Cycle of Excellence Award for most accessed article in Chem. Rev. in 2004. Currently, Dr. Garg is advising 3 graduate students research at Clarkson University (see website www.clarkson.edu/~rgarg). Students in her lab have received prestigious CCG Excellence Graduate Award (230th ACS National Meeting, 2005), Shipley Teaching Assistantship award (2005-2006), and CINF- Graduate Fellowship (231st ACS National Meeting, 2006) and summer internships in Pfizer, Wyeth etc. Dr. Garg is a co-author of 32 technical publications in international journals. She has presented her research in 37 national and international conferences as well as contributed two book chapters. Dr. Garg serves as expert reviewer for articles submitted in Mini-Reviews in Medicinal Chemistry, Current Medicinal Chemistry, Bioorganic Medicinal Chemistry, Bioorganic and Medicinal Chemistry Letters, Internet Electronic Journal of Molecular Design and Letters in Drug Design and Discovery.Host: Professor CC Jay Kuo, x04658, cckuo@sipi.usc.eduLocation: Grace Ford Salvatori Hall Of Letters, Arts & Sciences (GFS) - 116
Audiences: Everyone Is Invited
Contact: Gloria Halfacre
This event is open to all eligible individuals. USC Viterbi operates all of its activities consistent with the University's Notice of Non-Discrimination. Eligibility is not determined based on race, sex, ethnicity, sexual orientation, or any other prohibited factor. -
Analysis of Delay, Capacity, and Capacity Deficit in Multihop
Thu, Sep 28, 2006 @ 11:00 AM - 12:00 PM
Ming Hsieh Department of Electrical and Computer Engineering
Conferences, Lectures, & Seminars
Dr.Nabhendra Bisnik - Rensselaer Polytechnic InstituteMultihop wireless networks, such as wireless ad hoc, sensor, and mesh networks, have applications in a variety of fields like providing connectivity to communities, surveillance, monitoring, defense, etc. However scalability of such networks is marred by scarce bandwidth, broadcast nature of the wireless medium, and dynamic nature of network topology due to node mobility. In this talk we present analytical techniques for characterizing delay, capacity, and the capacity deficit caused by routing protocol overheads. We present a queuing theory approach to evaluate average end-to-end delay and maximum achievable per-node throughput in random access MAC based wireless ad hoc and mesh networks. The model takes into account the number of nodes, the random packet arrival process, the extent of locality of traffic, and the backoff and collision avoidance mechanisms of random access MAC. We model the random access multihop wireless networks as open G/G/1 queuing networks and use the diffusion approximation method for evaluating closed form expressions for average end to end delay. In order to characterize the impact of routing overheads on the actual capacity available to network users for transmitting data we present an information theoretic framework for analyzing the minimum routing overheadincurred by geographic routing in mobile ad hoc networks. We formulate the minimum routing overhead problem as a rate distortion problem and evaluate a lower bound on the minimum routing overhead incurred for routing packets with desired level of reliability. We characterize the effective transport capacity of ad hoc networks available to the users for transmitting data, after taking into account the minimum overheads that must be incurred for reliable routing. We also present results on the critical network size, above which the entire transport capacity of the network may be consumed by the routing overheads
Location: Frank R. Seaver Science Center (SSC) - 319
Audiences: Everyone Is Invited
Contact: Shane Goodoff
This event is open to all eligible individuals. USC Viterbi operates all of its activities consistent with the University's Notice of Non-Discrimination. Eligibility is not determined based on race, sex, ethnicity, sexual orientation, or any other prohibited factor.
