Conferences, Lectures, & Seminars
Events for November
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CS Colloq: Matt Zucker
Tue, Nov 10, 2009 @ 04:00 PM - 05:50 PM
Thomas Lord Department of Computer Science
Conferences, Lectures, & Seminars
Title: Combining Planning and Optimization for Rough Terrain LocomotionAbstract:Motion planning for rough-terrain legged robots is a difficult task, not only due to the high dimensionality of robot configuration spaces, but also due to the variety of kinematic, dynamic, and collision constraints which need to be met at all times. While producing optimal walking behavior is desirable, searching the space of all posible robot motions remains intractible for non-trival robotic systems. In this talk, I describe a hierarchy of planning and optimization algorithms that decomposes the planning problem into a sequence of decisions which can be efficiently solved in order to produce real-time locomotion over rough terrain. My software architecture has been successfully used over the past year to guide the LittleDog quadruped robot over a variety of terrain types. Beyond this specific software architecture, I will also discuss the ways in which machine learning and optimization techniques can increase the speed and quality of motion planning algorithms, and highlight lessons learned on how to decompose a high-level planning task into a tractable set of sub-problems.Bio:Matt Zucker is a Ph.D. candidate at the Robotics Institute at Carnegie Mellon University, where he works on motion planning for high degree-of-freedom robotic platforms. His research focuses on leveraging numerical optimization and machine learning techniques in order to improve planning speed and quality. Before graduate school, Matt worked from 2000-2005 writing software for autonomous underwater vehicles at Bluefin Robotics Corporation in Cambridge, MA. He expects to graduate from the Robotics Institute in the summer of 2010.Host: Prof. Stefan Schaal
Location: Seaver Science Library (SSL) - 150
Audiences: Everyone Is Invited
Contact: CS Front Desk
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CS Colloq: Prof. Vishal Misra
Thu, Nov 12, 2009 @ 04:00 PM - 05:30 PM
Thomas Lord Department of Computer Science
Conferences, Lectures, & Seminars
Speaker: Prof. Vishal Misra, Columbia University Title: A Shapley Value approach to Internet EconomicsHost: Prof. Leana GolubchikAbstract:Internet service providers (ISPs) depend on one another to provide global network services. However, the profit-seeking nature of the ISPs leads to selfish behaviors that result in inefficiencies and disputes in the network. From a macroscopic view, this concern is at the heart of the Network Neutrality debate, which asks for an appropriate compensation structure that satisfies all types of ISPs and content providers.In this work, we design a profit-sharing mechanism based on the Shapley value originated from Coalition Game Theory. We derive closed-form profit solutions for structured ISP topologies and develop a dynamic programming procedure to calculate solutions for general topologies. Based on these solutions, we draw some implications on the bilateral settlements between ISPs. In practice, these results provide guidelines for ISPs to solve disputes and negotiate stable and incentive settlements and for governments to establish regulatory policies for the Internet industry.We then further extend the concept of Shapley Values to the scenario of Peer to Peer systems, where the Peers get compensated for reducing the cost of content distribution In general, the drawback of the Shapley Value mechanism is its computational complexity. We prove that this it is not the case for (very) large systems. As the number of peers receiving the service becomes large, the Shapley value received by each player approaches a hybrid fluid- atomic limit, leading to a simple closed form expression for any cost function, and simplifies even further in some scenarios of interest. We apply our technique to several scenarios for wired and wireless networks, proving that it leads to stable structure providing savings for bandwidth and energy costs.Bio:Vishal Misra is an Associate Professor in the Computer Science Department at Columbia University. He has received an NSF CAREER Award, a DoE CAREER Award and IBM Faculty Awards. His research emphasis is on mathematical modeling of computer systems, bridging the gap between practice and analysis. His recent work includes the areas of Internet economics, wireless, scheduling mechanisms and peer to peer systems. He has served as the guest editor for the Journal of Performance Evaluation, was TPC co-chair of Sigmetrics 2008, and serves on the editorial board of IEEE/ACM Transactions on Networking and Elsevir Journal of Performance Evaluation.
Location: Seaver Science Library (SSL) - 150
Audiences: Everyone Is Invited
Contact: CS Front Desk
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CS Colloq: Dr. Marco Papa
Thu, Nov 19, 2009 @ 04:00 PM - 05:00 PM
Thomas Lord Department of Computer Science
Conferences, Lectures, & Seminars
Title: The Radio for iPhone App ecosystem: A Case Study Speaker: Dr. Marco Papa (Intersect World LLC) Host: Prof. Ellis Horowitz Abstract:
With over 100,000 apps, 50,000 independent developers and two billion downloads, iPhone App development is one of the few job descriptions that have withstood the economy downturn. Many of the iPhone Apps make use of a number of Web Technologies: HTTP, HTML, XML, XSLT, JSON, CGI Perl, PHP, and Java. Using the Radio App for the iPhone as an example, this talk will provide a behind the scenes look at the role that these Web Technologies have had in helping develop, deliver, market, maintain and monitor one such application. Bio:
Marco Papa is currently Chief Technologist and Manager of Training and Research at the Los Angeles Superior Court, the largest Court system in the world. He is also a lecturer in Web Technologies at USC and the owner of Intersect World LLC, an IP consulting and iPhone development company. He received a BS in Electronic Engineering from the University of Bologna, Italy, and a Ph.D. in Computer Science from the University of Southern California. From 1994 to 2002 Dr. Papa held the positions of CTO at Luckman Interactive and CareerPath, and Vice President of Engineering at US Interactive and Xceed.
Location: Seaver Science Library (SSL) - 150
Audiences: Everyone Is Invited
Contact: CS Front Desk
