Computer Science Seminar Series - Spring 2009
Time 3 - 4 PM

3/6/09 Dr. Shelley Zhang
Generalized Integrated Learning Architecture
UMass Dartmouth
DION 101
Florin Constantin
Reservations with costly cancellations in an online game-theoretic model
Harvard University
Dion 311 (2-3PM)
Kai Xing
Channel Resource Management in Multi-channel Wireless Networks
George Washington University DION 101
Satyajayant Misra
Relay Node Placement in Wireless Sensor Networks for Connectivity and Survivability
Arizona State University
DION 305 (2-3PM)
Simone Ludwig
Ontology-driven Service Discovery on the Web and Artificial Life Approaches on the Grid
University of Saskatchewan
DION 101
(10 -11AM)
Ken Lee
Z-SKY: An Efficient Skyline Query Processor based on Z-order
The Pennsylvania State University at University Park
DION 101
(3:45 -4:45PM)
4/24/09 Mengchu Zhou
Web Service Composition: A Petri Net Approach
New Jersey Institute of Technology (NJIT)
DION 101

Date: 3/06/09
Title: Generalized Integrated Learning Architecture
Abstract: In this talk we present an ensemble architecture for learning complex problem solving techniques from expert demonstration.
The key feature of our ``Generalized Integrated Learning Architecture" (GILA) is a set of integrated learning and reasoning (ILR) systems coordinated by a central meta-reasoning executive (MRE). Each ILR learns independently from the same training example and contributes
to problem-solving in concert with other ILRs as directed by the MRE. We describe the application of this novel learning and problem solving architecture to the domain of airspace management, where multiple requests for the use of airspace need to be reconciled and managed automatically.  Formal evaluations show that our system performs as well as or better than humans after learning from the same training data. Further, GILA outperforms any individual ILR run in isolation, thus demonstrating the power of the ensemble architecture for learning and problem solving.

: 3/10/09
Title: Reservations with costly cancellations in an online game-theoretic model
Abstract: We initiate the worst-case study of reservations (advance-booking), motivated by the lack of this feature from current sponsored search systems. We introduce a simple model for auctioning reservations, in which impatient, selfish, buyers with private values arrive sequentially and place a bid. With adversarial arrivals and values, any algorithm can perform arbitrarily worse than the offline optimum. We show the effectiveness of a novel, practical assumption: the seller can cancel at any time an earlier reservation, resulting in a utility loss to the reservation holder of a fraction of her value. Our main result is an online algorithm and pricing scheme with many desirable game-theoretic and optimization properties. Winners have an incentive to be honest. Bidding one's true value is never worse than any lower bid. Our mechanism's revenue is within a constant fraction of the a
posteriori revenue of the Vickrey-Clarke-Groves mechanism. Our mechanism's efficiency is within a constant fraction of the a posteriori optimally efficient solution. If efficiency also takes into account the utility losses of buyers whose reservation was canceled, our mechanism can match an upper bound on the competitive ratio of any deterministic online algorithm. Based on joint work with Jon Feldman, Muthu Muthukrishnan and Martin Pal.

Date: 3/13/09
Title: Channel Resource Management in Multi-channel Wireless Networks
Abstract: Multi-channel wireless networking is a key enabling technology in the next generation wireless networks. Through the usage of non-overlapping channel resources, users can communicate with each other simultaneously over different channels, and thus the network performance can be significantly improved by exploring concurrent transmissions. In such a multi-channel environment, a natural question is how to manage the channel resources. Relevant issues include channel assignment support for both unicast and local broadcast, interference mitigation, throughput optimization, switching delay, overhead reduction, etc. In this talk, I will first provide a brief overview of the background and design principles of channel resource management in multi-channel networking environments. Next, I will address the challenges stated above and introduce two channel resource management schemes, one for unicast and the other for local broadcast. I will show how interference-free communication can be achieved for both unicast and local broadcast under certain conditions, and how the channel management scheme can reach 100% throughput for unicast. Additionally, I will discuss some other related issues such as network scalability and connectivity. Lastly, I will talk about some future research directions for this work and how it fits into my overall research vision.

Date: 3/25/09
Title: Relay Node Placement in Wireless Sensor Networks for Connectivity and Survivability
Abstract: Wireless Sensor Networks (WSNs) have been projected as one of the popular networks of the future. Their infrastructureless nature, ease of deployment, and relative cost-effectiveness has made them suitable for applications in both the military and the civilian domains. Despite the inherent advantages of WSNs, there exist fundamental problems that need to be solved to expedite their adoption. One such area with extensive research potential is the design of algorithms for energy aware routing, improvement in lifetime, and survivability. To prolong network lifetime while meeting certain network specifications, such as connectivity and survivability, researchers have proposed to deploy in a WSN a small number of relay nodes (RNs) whose main function is to communicate the data from the sensor nodes (SNs) to the base stations (BSs). Problems in this area are studied under the theme of relay node placement.

This talk aims to provide a holistic view of the relay node placement problem. It presents the state of the art for some of the problems and the existing challenges. The talk deals with single and two-tiered wireless sensor networks, constrained and unconstrained relay node placement, and network design to satisfy connectivity and survivability constraints for the network. It concentrates on the problem of relay node placement in a single-tiered network setting, under constrained relay node deployment, for ensuring connectivity and survivability.

Date: 3/27/09
Title: Ontology-driven Service Discovery on the Web and Artificial Life Approaches on the Grid
Abstract: Two research projects will be presented during this talk. The first project addresses one essential requirement of service-oriented environments which is the ability to locate services of interest. As traditional approaches to service discovery have generally relied on simple syntax matches, the proposed approach is based on semantic descriptions stored in ontologies and reasoning capabilities which are applied to these semantic descriptions. The approach and the implementation of a prototype will be presented and discussed.

The second project addresses the problem of load balancing in a Grid environment. Prior work has addressed load balancing using a centralized approach, however, as this can lead to a single point of failure, distributed load balancing using ant colony and particle swarm approaches have been investigated. The two approaches are implemented in a simulation environment (GridSim) and different performance measures (e.g. makespan, load balancing level, etc.) are evaluated.

Date: 3/31/09
Title: Z-SKY: An Efficient Skyline Query Processor based on Z-order
Abstract: In decision support applications, we are often interested in finding
optimal data points from a large set of data points in a
multidimensional space. Recently, a skyline query has been proposed to
retrieve those optimal data points, as a subset of data points that are
not dominated by any other point in a database. A data point p is said
to dominate another point q if p is strictly better in at least one
dimension than q and p is not worse than q for all the remaining
dimensions. While data cardinality or dimensionality increases,
efficient evaluation of the skyline query is challenging. Observing a
strong connection between Z-order space filling curve (or Z-order curve
for short) and skyline processing strategies, we design Z-SKY, a query
processor that efficiently supports skyline query processing, skyline
result updates and several skyline query variants. At the core of Z-SKY
is a new index structure called ZBtree that indexes data points based on
Z-order curve, developed upon which a suite of innovative and efficient
algorithms. All of them are developed based on coherent ideas and
concepts. In this talk, a detailed skyline query analysis, the design of
Z-SKY as well as the performance evaluation will be presented.

Date: 4/24/09
Title: Web Service Composition: A Petri Net Approach
Abstract: Web service framework has evolved to become an important paradigm for distributed computing. When any single web service fails to accomplish service requestor’s multiple function requirements, multiple web services need to be dynamically configured together to form a web service composition. This work deals with automatic configuration of services under practical constraints. First, according to the customized or application-specific web service functional requirement, discover all the web services. Second, by analyzing function decomposition and function selection on the service interface information, build a complete service functional dependency configuration net based on Petri nets. Third, choose and compute the quality-of-service (QoS) attributes for the whole configuration. A transformation method is utilized to change non-linear aggregation functions to linear ones. Relative importance or value trade-offs of different attributes are represented through subjective preference or perception. Fourth, the QoS attribute value for each real web service is gained. An association algorithm translates and compiles QoS attributes. Finally, the linear programming problem is formulated and solved. The best configuration is found and sensitivity analysis is carried out. The concepts and developed algorithms can be readily put into industrial applications. This talk will cover some basic knowledge of Petri nets as a fundamentally important modeling tool for discrete event systems and their particular applications to modeling, analysis and composition of web services.

Computer Science Seminar Series - Fall 2008
Time 3 - 4PM

Elizabeth Winiarz, Science Librarian
Library Resources and Services for Computer and Information Science - How to Save Yourself A Lot of Time When Doing Research
UMD Library DION 101
Dr. Vinod Vokkarane
High-Speed Service-Oriented Optical Internet
UMass Dartmouth
DION 101
Dr. Iren Valova
Role Of Initialization In SOM Networks - Study Of Self-Similar Curve Topologies
UMass Dartmouth DION 101

Graduate Student Research Presentation
UMass Dartmouth DION 101
Dan Reddy
Software Assurance
DION 101

Date: 10/31/08
Title: High-Speed Service-Oriented Optical Internet
Abstract: Many emerging next-generation Internet applications, such as videoconferencing, multimedia distribution, and high-performance scientific computing, are characterized by high bandwidth requirements, single-source and multi-destination communication paradigms, strict QoS requirements with respect to delay and loss, and high reliability requirements.  In order to support these diverse requirements, emerging networks must be able to manage resources in a flexible manner. We present the latest research on next-generation service-oriented optical Internet architectures and protocols performed at UMass Dartmouth.  We will discuss new services provided at the optical layer and how it will be beneficial to next-generation Internet applications.  The talk will specifically discuss new algorithms and protocols for implementing manycast communication service and providing high-speed reliable communication service.
Speaker Bio: Dr. Vinod Vokkarane is the Assistant Professor of Computer and Information Science at the University of Massachusetts Dartmouth.  He is the Director of the Advanced Computer Networks Laboratory (ACN).  He received the B.E. degree with Honors in Computer Science and Engineering from the University of Mysore, India in 1999, the M.S. degree in Computer Science from the University of  Texas at Dallas in 2001, and the Ph.D. degree in Computer Science from the University of Texas at Dallas in 2004. Dr. Vokkarane's research interests include the design and analysis of architectures and protocols for next-generation optical and wireless networks.  He has been involved in the organization of several conferences and symposia on optical networking.  He has published over 40 research papers in refereed journals and conferences,  including a paper that received the Best Paper Award at IEEE GLOBECOM 2005. He is also a recipient of the Texas Telecommunication Engineering Consortium Fellowship 2002-03, and the University of Texas at Dallas Best Dissertation Award 2003-04.  Dr. Vokkarane is the co-author of a book, "Optical Burst Switched Networks," Springer, 2005.  Dr. Vokkarane has received research grants from National Science Foundation (NSF), United States Marines Corps (USMC), and regional networking companies.

Date: 11/21/08
Abstract: This work investigates the initialization process in SOM. This is of importance because of the issue of network linearity and, subsequently, the quality of the produced map. We discuss 1D classical SOM, i.e. the algorithm presented by Kohonen, and experiment with three different approaches to initialization - random, random with training or priming, and using self-similar curves to initially position the neurons. Our results show that, while the network will eventually untangle when random initialization is used, this will occur at the 100,000+ epoch. With priming or self-similar curves, the final, linear map is produced much earlier, i.e. 10,000th epoch at the most. The benefits of this are obvious with significantly reduced time to produce a usable map of the input space.

Date: 12/12/08
Title: Software Assurance
Abstract:  Software Assurance: As Customers (especially governments) buy Commercial Off the Shelf Software (COTS) what level of assurance should
they expect regarding how secure the software is as built and implemented ?  This session will provide an overview of what exists today and what trends are emerging related to software assurance from a government and industry perspective.  Included will be a discussion of how these trends could influence the Systems Engineering or IT skills needed in the field and new employment opportunities that may exist.
Speaker Bio: Dan Reddy is a Consulting Product Manager in the Product Security Office at EMC, a group that is charged with the continued driving of security improvements into EMC products. In his various roles within his 12 years at EMC he has been consulting with EMC Customers around product security issues and has been involved in numerous IT software development projects. Prior to joining EMC, Dan spent 15 years at New England Electric, a
major electric utility with nationally critical infrastructure where held a variety of IT and business roles including Manager of Technical Services in IT and Staff Assistant to the Chief Operating Officer. He also teaches Computer Science courses at Quinsigamond Community College in Massachusetts where has taught for over 30 years. He holds and M. Ed. in Computer Science from Worcester State College and a B.A. from Tufts University in Education.