Select a calendar:
Filter November Events by Event Type:
SUNMONTUEWEDTHUFRISAT
Events for November 25, 2008
-
A Sequential Stochastic Security System Design Problem for Aviation Security
Tue, Nov 25, 2008 @ 10:00 AM - 11:00 AM
Daniel J. Epstein Department of Industrial and Systems Engineering
University Calendar
DANIEL J. EPSTEIN DEPARTMENT OF INDUSTRIAL AND SYSTEMS ENGINEERING SEMINAR"A Sequential Stochastic Security System Design Problem for Aviation Security"Dr. Sheldon H. JacobsonProfessor, Willett Faculty Scholar, Department of Computer Science, University of Illinois - UrbanaABSTRACT: Passenger screening is a critical component of aviation security systems. This paper introduces the sequential stochastic security design problem (SSSDP), which models passenger and carry-on baggage-screening operations in an aviation security system. SSSDP is formulated as a two-stage model, where in the first stage security devices are purchased subject to budget and space constraints, and in the second stage a policy determines how passengers that arrive at a security station are screened. Passengers are assumed to check in sequentially, with passenger risk levels determined by a prescreening system. The objective of SSSDP is to maximize the total security of all passenger-screening decisions over a fixed time period, given passenger risk levels and security device parameters. SSSDP is transformed into a deterministic integer program, and an optimal policy for screening passengers is obtained. Examples are provided to illustrate these results, using data extracted from the Official Airline Guide.TUESDAY, NOVEMBER 25, 2008, ANDRUS GERONTOLOGY BUILDING (GER) ROOM 309, 10:00 – 11:00 AMSPEAKER BIO: Sheldon H. Jacobson is a Professor, Willett Faculty Scholar, and Director of the Simulation and Optimization Laboratory in the Department of Computer Science at the University of Illinois. He has a B.Sc. and M.Sc. (both in Mathematics) from McGill University, and a M.S. and Ph.D. (both in Operations Research and Industrial Engineering) from Cornell University. His theoretical research interests include the stochastic analysis and design of heuristics for intractable discrete optimization problems. His applied research interests address problems in the areas of homeland security and health-care delivery systems. His research has been recognized with several awards, including the Aviation Security Research Award by Aviation Security International, the International Air Transport Association, and the Airports Council International (in 2002), a Best Paper Award in IIE Transactions Focused Issue on Operations Engineering (in 2003) and a Guggenheim Fellowship by the John Simon Guggenheim Memorial Foundation (in 2003). His research has been published in a wide spectrum of journals, and he has received research funding from several government agencies and industrial partners, including the National Science Foundation and the Air Force Office of Scientific Research.
Location: Ethel Percy Andrus Gerontology Center (GER) - 309
Audiences: Everyone Is Invited
Contact: Georgia Lum
-
Information Theoretic Approaches for Utilizing Packet Timings in Networks
Tue, Nov 25, 2008 @ 10:00 AM - 11:00 AM
Ming Hsieh Department of Electrical and Computer Engineering
Conferences, Lectures, & Seminars
SPEAKER: Todd P. Coleman
University of Illinois at Urbana-ChampaignAbstract: The use of network services and distributed applications is becoming more and more prevalent as time progresses. This motivates the desire to use advanced communication, control, and prediction strategies to enable these distributed applications - without perturbing the normal operation of networks. Recently, researchers and practitioners have begun espousing the use of the timing modality to afford new degrees of freedom. Here we discuss utilizing packet timings in networks in order to gather and convey information. We specifically speak to: (a) the development of sparse graph codes combined for communicating with packet timings across queuing timing channels that enables efficient reliable decoding at rates approaching fundamental limits, and (b) closed-form characterization of the rate-distortion function of a Poisson process with a queuing distortion measure. If time permits, we will show how the technique used in (b) enables a simple memoryless proof to the capacity of the celebrated "Bits through queues" channel model of Anantharam and Verdu and enables new converses to multiterminal timing channel information theoretic problems.Location: Hughes Aircraft Electrical Engineering Center (EEB) - 248
Audiences: Everyone Is Invited
Contact: Gerrielyn Ramos
-
Forget him (or her) and keep on moving: Making mobile social networks navigable
Tue, Nov 25, 2008 @ 11:00 AM
Thomas Lord Department of Computer Science
Conferences, Lectures, & Seminars
Speaker: Augustin Chaintreau, Thomson, Paris
Host: Prof. Ramesh GovindanAbstract:
A network is navigable if a simple decentralized scheme allows efficient routing (i.e. in a polylogarithmic number of steps). Previous works have shown that general classes of graphs can be made navigable by adding few links according to an appropriate distribution. However, for most of this graphs, navigability is sensitive to small deviations from this distribution. Moreover, it seems difficult for the nodes to manage such a link addition in a distributed way. In spite of some efforts, and evidence of the "small-world phenomenon" in social networks, no model currently proves the emergence of navigability from local dynamics.Here we prove that navigability emerges from nodes own mobility and memory. Inspired by emerging opportunistic mobile networks using human carried devices (a.k.a. Pocket switched networks), we model a network where nodes move (in our case, according to a random walk in dimension d), and may opportunistically create connections as they meet physically. Once established, these connections are randomly maintained or forgotten, based only their current age. We prove that this simple setting allows one to create navigable networks. We present a few applications of these techniques to design opportunistic spatial gossip, and discuss the upcoming challenges in relation with recent experiences on using social software for opportunistic mobile networks.(this is a joint work with Pierre Fraigniaud and Emmanuelle Lebhar, from CNRS-Universite Paris Diderot and CMM-Universidad de Chile)Location: Kaprielian Hall (KAP) - 163
Audiences: Everyone Is Invited
Contact: CS Colloquia
