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September 3
Wednesday 1:30pm
369 Link Hall
Dr. Jin Li
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Title: Utility Maximization for P2P Applications and Its Application in Optimizing Multi-party Conferencing
Speaker: Dr. Jin Li, Microsoft Research
Abstract: Peer-to-Peer (P2P) applications are tremendously popular on today's Internet, and applications like file sharing perform well even with thousands or millions of peers. In the first part of the talk, we survey various infrastructure in the internet: the data
center, the CDN, and the end user. We show that P2P is an essential component to support massive data delivery in the Internet, such as IPTV.
In the second part of the talk, we investigate the problem of optimized P2P based multiparty video conference. We study the problem of utility maximization in P2P applications, in which aggregate application-specific utilities are maximized by running distributed algorithms on P2P nodes. Using recent discoveries in optimal tree structure for P2P content delivery, we develop a new formulation for multicast utility maximization problem.
This formulation is unique in the sense that it not only eliminates some mathematical difficulties as compared to previous formulations, but also leads to practical solutions. We develop Primal and Primal-dual distributed algorithms to maximize the aggregate utility. We prove that these algorithms converge to the optimal solution of the utility maximization problem exponentially fast. Furthermore, they can be implemented by utilizing only the end-to-end delay measurement between
P2P nodes. As such, it can be readily deployed on today's Internet. To support this claim, we have implemented the Primal-dual algorithm to design a peer-assisted multi-party conferencing system and evaluated its performance through actual experiments on a small scale test bed, as well as on the Internet.
Bio:
Dr. Jin Li is currently a principal researcher managing the communication system subgroup at Microsoft Research Redmond. He has worked in a diversified research field, ranging from audio/image/video compression, virtual environment and graphic compression, audio/video streaming, realtime audio/video conferencing, peer-to-peer content delivery, distributed storage, etc.. He received his Ph.D. in electrical engineering from Tsinghua University (Beijing, China) in 1994. From 1994 to 1996, he served as a Research Associate at the University of Southern California (USC). From 1996 to 1999, he was a member of the technical staff at the Sharp Laboratories of America (SLA), (Camas, WA), and represented the interests of SLA in the JPEG2000 and MPEG4 standardization efforts. He was a researcher/project leader at Microsoft Research Asia (Beijing, China) from 1999 to 2000.
Dr. Li has 90+ referred conference and journal papers. Dr. Li is an Area Editor for the Journal of Visual Communication and Image Representation (Academic Press) and Journal of P2P networking applications. He was an associate editor of IEEE Transactions on Multimedia. He is a senior member of IEEE. He was the recipient of the 1994 Ph.D. thesis award from
Tsinghua University and the 1998 Young Investigator Award from SPIE Visual Communication and Image Processing.
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September 17
Wednesday 1:30pm
369 Link Hall
Prof. Nader Engheta
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Title: Circuits with Light at the Nanoscale:
Metananocircuits and Metactronics
Speaker: Professor Nader Engheta, Nedwill Ramsey Professor University of Pennsylvania, Department of Electrical and Systems Engineering, Philadelphia, Pennsylvania
Abstract: Imagine circuit elements so small that you could fit many of them in a cell! What could you do with such optical nanocircuits? Would you be able to use them in wireless gadgets at nanoscales, like a “nanoradio”, that may connect our nanoworlds? Could these tiny optical nanocircuits be coupled with biological entities and thus provide nanoscale sensors? The fields of metamaterials and plasmonic optics may provide road maps for such futuristic nanocircuits and wireless nanosystems and sensors. We have been developing and investigating some of the fundamental concepts and key features of metaplasmonic structures, devices, and circuits. These components may be envisioned as a tapestry of nanostructures of sizes much smaller than the wavelengths of light. This field, for which I have coined the term metactronics, addresses metamaterial-inspired optical nanocircuits and systems (N. Engheta, Science, 317, 1698-1702, 2007). . In my group, a variety of ideas for nanocircuit functions, optical antennas and sensors for beam shaping and photonic wireless at the nanoscale, optical nanoscopy, nanospectrometer for molecular spectroscopy, cloaking of particles, nanotagging and barcodes based on these optical circuits are being studied. In this talk, I will give an overview of these studies, present insights into these findings, and forecast future ideas and road maps in these areas.
Bio: Nader Engheta is the H. Nedwill Ramsey Professor of Electrical and Systems Engineering, and Professor of Bioengineering, at the University of Pennsylvania. He received his B.S. degree in EE from the University of Tehran, and his M.S and Ph.D. degrees in EE from Caltech. Selected as one of the Scientific American Magazine 50 Leaders in Science and Technology in 2006 for developing the concept of optical lumped nanocircuits, he is a Guggenheim Fellow, an IEEE Third Millennium Medalist, IEEE Fellow, Optical Society of America Fellow, and the recipient of the 2008 George H. Heilmeier Award for Excellence in Research from UPenn, the Fulbright Naples Chair Award, NSF Presidential Young Investigator award, the UPS Foundation Distinguished Educator term Chair, and several teaching awards including the Christian F. and Mary R. Lindback Foundation Award and S. Reid Warren, Jr. Award. His current research activities span a broad range of areas including metamaterials and plasmonics, nanooptics and nanophotonics, biologically-inspired sensing and imaging, miniaturized antennas and nanoantennas, physics and reverse-engineering of polarization vision in nature, mathematics of fractional operators, and physics of fields and waves phenomena. He has given numerous keynote, invited, and plenary talks on these topics. He has co-edited the book entitled “Metamaterials: Physics and Engineering Explorations” by Wiley-IEEE Press, 2006.
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