February 2015 - talks - lists.cs.princeton.edu

Colloquium Speaker Simon Peter, Mon Feb 23, 12:30pm
by Nicole E. Wagenblast 17 Feb '15

17 Feb '15

Colloquium Speaker Simon Peter, University of Washington Monday, February 23, 12:30pm Computer Science 105 Building an Operating System for the Data Center Data centers run a range of important applications with ever increasing performance demands, from cloud and server computing to Big Data and eScience. However, the scaling of CPU frequency has stalled in recent years, leading to hardware architectures that no longer transparently scale software performance. Two trends stand out: 1) Instead of frequency, hardware architectures increase the number of CPU cores, leaving complex memory system performance and CPU scheduling tradeoffs exposed to software. 2) Network and storage I/O performance continues to improve, but without matching improvements in CPU frequency. Software thus faces ever increasing I/O efficiency demands. In my research, I address how operating systems (OSes) can handle these growing complexity and performance pressures to avoid becoming the limiting factor to performance. I first explain how current OS architecture is already inadequate to address these trends, limiting application performance. I then present how the OS can be redesigned to eliminate the performance limitations without compromising on existing features or application compatibility. I finish with an outlook on how these hardware trends affect software in the future and present ideas to address them. Simon is a postdoctoral research associate at the University of Washington, where he leads research in operating systems and networks. His postdoctoral advisors are Tom Anderson and Arvind Krishnamurthy. Simon received a Ph.D. in Computer Science from ETH Zurich in 2012 and an MSc in Computer Science from the Carl-von-Ossietzky University Oldenburg, Germany in 2006. Simon's research focus is on data center performance issues. For his work on the Arrakis high I/O performance operating system, he received the Jay Lepreau best paper award (2014) and the Madrona prize (2014). Previously, Simon has worked on the Barrelfish multicore operating system and conducted further award-winning systems research at various locations, including MSR Silicon Valley, MSR Cambridge, Intel Labs Germany, UC Riverside, and the NSF.

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Colloquium Speaker Morgan Dixon, Wed Feb 18, 12:30pm
by Nicole E. Wagenblast 17 Feb '15

17 Feb '15

Colloquium Speaker Morgan Dixon, University of Washington Wednesday, February 18, 12:30pm Computer Science 105 Unlocking Interaction via Pixel-Based Reverse Engineering User interface software has become a victim of its own success. Graphical event-driven systems are the dominant user interface for computational devices, realized via popular user interface toolkits. However, this success has induced a lock-in effect that demonstrably stifles innovation. For example, human-computer interaction researchers regularly propose new interaction techniques for desktop and mobile devices, enhancements for people with disabilities, better support for localization, and new collaboration facilities. However, these techniques rarely make it outside the laboratory because existing software tools cannot support them. Changing the ecosystem would require a mass adoption of new tools, and most of the applications we use today would need to be rewritten. I will describe an approach that unlocks existing graphical application without their source code and without their cooperation, making it possible to explore and deploy many promising ideas in the context of existing real-world interfaces. Prefab is a system that reverse-engineers graphical interfaces from raw pixels. I will show how Prefab can be used to augment user interfaces with a variety of techniques, including accessibility enhancements, improved input for touch screens, UI language translation, and end-user customization. Some of these enhancements were proposed in the literature over the last two decades, but prior to Prefab they had been considered nearly impossible to deploy in practice. Morgan Dixon is a PhD student in Computer Science & Engineering at the University of Washington working with James Fogarty. His research is centered around designing, building, and studying systems that make user interface software more flexible and extensible. He has also worked on novel interaction techniques for accessibility, dual-display mobile devices, health technologies, crossing-based interfaces, and data analysis tools. Morgan received a B.S. in Computer Science and Mathematics from the University of Maryland in 2008, and an M.S. from the University of Washington in 2010. His work on Prefab received a CHI Best Paper Award, and he was named a Microsoft Research PhD Fellow in 2011.

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Colloquium Speaker Walter Lasecki Today, 12:30pm
by Nicole E. Wagenblast 17 Feb '15

17 Feb '15

Colloquium Speaker Walter S. Lasecki , University of Rochester Tuesday, February 17, 2015 - 12:30pm Computer Science 105 Crowd-Agents: Creating Crowd-Powered Interactive Systems I create and deploy interactive systems that use a combination of human and machine intelligence to operate robustly in real-world settings. Unlike prior work in human computation, my “Crowd Agent” model allows crowds of people to support continuous real-time interactive systems that require ongoing context. For example, Chorus allows multi-session conversations with a virtual personal assistant; Scribe allows non-experts to caption speech in real time for deaf and hard of hearing users, where prior approaches were either not accurate enough, or required professionals with years of training; and Apparition allows designers to rapidly prototype new interactive interfaces from sketches in real time. In this talk, I will describe how computationally-mediated groups of people can solve problems that neither people nor computers can solve alone, and scaffold AI systems using the real-world data they collect. Walter S. Lasecki is a Computer Science Ph.D. candidate at the University of Rochester working with Jeffrey Bigham (CMU) and James Allen (Rochester). He creates interactive intelligent systems that are robust enough to be used in real-world settings by combining both human and machine intelligence to exceed the capabilities of either. Mr. Lasecki received a B.S. in Computer Science and Mathematics from Virginia Tech in 2010, and an M.S. from the University of Rochester in 2011. He was named a Microsoft Research Ph.D. Fellow in 2013, and has held visiting research positions at Stanford and Google[x]. Since 2013, he has been a Visiting Researcher at Carnegie Mellon University.

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Colloquium Speaker Walter Lasecki Tues Feb 17, 12:30pm
by Nicole E. Wagenblast 16 Feb '15

16 Feb '15

Colloquium Speaker Walter S. Lasecki , University of Rochester Tuesday, February 17, 2015 - 12:30pm Computer Science 105 Crowd-Agents: Creating Crowd-Powered Interactive Systems I create and deploy interactive systems that use a combination of human and machine intelligence to operate robustly in real-world settings. Unlike prior work in human computation, my “Crowd Agent” model allows crowds of people to support continuous real-time interactive systems that require ongoing context. For example, Chorus allows multi-session conversations with a virtual personal assistant; Scribe allows non-experts to caption speech in real time for deaf and hard of hearing users, where prior approaches were either not accurate enough, or required professionals with years of training; and Apparition allows designers to rapidly prototype new interactive interfaces from sketches in real time. In this talk, I will describe how computationally-mediated groups of people can solve problems that neither people nor computers can solve alone, and scaffold AI systems using the real-world data they collect. Walter S. Lasecki is a Computer Science Ph.D. candidate at the University of Rochester working with Jeffrey Bigham (CMU) and James Allen (Rochester). He creates interactive intelligent systems that are robust enough to be used in real-world settings by combining both human and machine intelligence to exceed the capabilities of either. Mr. Lasecki received a B.S. in Computer Science and Mathematics from Virginia Tech in 2010, and an M.S. from the University of Rochester in 2011. He was named a Microsoft Research Ph.D. Fellow in 2013, and has held visiting research positions at Stanford and Google[x]. Since 2013, he has been a Visiting Researcher at Carnegie Mellon University.

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Aleksey Boyko will present his FPO on Friday, February 20, 2015 at 11am in CS 302
by Nicki Gotsis 13 Feb '15

13 Feb '15

Aleksey Boyko will present his FPO on Friday, February 20, 2015 at 11am in CS 302. The members of his committee are below: Tom Funkhouser (advisor) Readers: Brian Kernighan and Szymon Rusinkiewicz Non Readers: Adam Finkelstein and Jianxiong Xiao A copy of his thesis, is available in Room 310. Everyone is invited to attend his talk.

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Colloquium Speaker Cynthia Dwork, Thurs Feb 19, 12:30pm
by Nicole E. Wagenblast 13 Feb '15

13 Feb '15

Colloquium Speaker Cynthia Dwork, Microsoft Research Thursday, February 19, 12:30pm Computer Science 105 Privacy in the Land of Plenty Privacy-preserving data analysis has a large literature that spans several disciplines. "Differential privacy" -- a notion tailored to situations in which data are plentiful -- has provided a theoretically sound and powerful framework, and given rise to an explosion of research. We will review the definition of differential privacy, describe some algorithmic contributions, and conclude with a surprising application. Cynthia Dwork, Distinguished Scientist at Microsoft Research, is renowned for placing privacy-preserving data analysis on a mathematically rigorous foundation. A cornerstone of this work is differential privacy, a strong privacy guarantee frequently permitting highly accurate data analysis. Dr. Dwork has also made seminal contributions in cryptography and distributed computing, and is a recipient of the Edsger W. Dijkstra Prize, recognizing some of her earliest work establishing the pillars on which every fault-tolerant system has been built for decades. She is a member of the National Academy of Sciences and the National Academy of Engineering, and a Fellow of the American Academy of Arts and Sciences.

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Colloquium Speaker Morgan Dixon, Wed Feb 18, 12:30pm
by Nicole E. Wagenblast 12 Feb '15

12 Feb '15

Colloquium Speaker Morgan Dixon, University of Washington Wednesday, February 18, 12:30pm Computer Science 105 Unlocking Interaction via Pixel-Based Reverse Engineering User interface software has become a victim of its own success. Graphical event-driven systems are the dominant user interface for computational devices, realized via popular user interface toolkits. However, this success has induced a lock-in effect that demonstrably stifles innovation. For example, human-computer interaction researchers regularly propose new interaction techniques for desktop and mobile devices, enhancements for people with disabilities, better support for localization, and new collaboration facilities. However, these techniques rarely make it outside the laboratory because existing software tools cannot support them. Changing the ecosystem would require a mass adoption of new tools, and most of the applications we use today would need to be rewritten. I will describe an approach that unlocks existing graphical application without their source code and without their cooperation, making it possible to explore and deploy many promising ideas in the context of existing real-world interfaces. Prefab is a system that reverse-engineers graphical interfaces from raw pixels. I will show how Prefab can be used to augment user interfaces with a variety of techniques, including accessibility enhancements, improved input for touch screens, UI language translation, and end-user customization. Some of these enhancements were proposed in the literature over the last two decades, but prior to Prefab they had been considered nearly impossible to deploy in practice. Morgan Dixon is a PhD student in Computer Science & Engineering at the University of Washington working with James Fogarty. His research is centered around designing, building, and studying systems that make user interface software more flexible and extensible. He has also worked on novel interaction techniques for accessibility, dual-display mobile devices, health technologies, crossing-based interfaces, and data analysis tools. Morgan received a B.S. in Computer Science and Mathematics from the University of Maryland in 2008, and an M.S. from the University of Washington in 2010. His work on Prefab received a CHI Best Paper Award, and he was named a Microsoft Research PhD Fellow in 2011.

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Fwd: EE Department Seminar - Guy Bresler, 2/19
by Jennifer Rexford 12 Feb '15

12 Feb '15

> > Speaker: > Dr. Guy Bresler > Title: > Learning statistical structure in data: efficient estimation of graphical models > Day: > Thursday, February 19, 2015 > > > Time: > 4:30 pm > Room: > B205, E-Quad > Host: > Prof. Emmanuel Abbe > > > > > > > > > Abstract: > Graphical models are a powerful framework used to succinctly represent high-dimensional distributions, and are at the core of modern large-scale statistical inference. The graph underlying such a distribution specifies interactions between the variables, and explicitly captures the computational aspect inherent to statistical tasks. For unstructured settings such as those found in social networks, biology, and finance, a central problem is to determine a good model from observed data. > > Learning graphical models from high-dimensional data is computationally challenging, and many different algorithms have been proposed over the years. Nevertheless, it is not clear what classes of models can be learned efficiently. In this talk we explore the problem from several angles and obtain a relatively unified view of what determines the computational complexity of learning graphical models. > > > Bio: > Guy Bresler is currently a postdoctoral associate at the Laboratory for Information and Decision Systems at MIT. His research interests are at the interface of computation, statistics, and information theory. He received his Ph.D. from the Dept. of Electrical Engineering and Computer Sciences at UC Berkeley, and his B.S. in electrical and computer engineering and M.S. in mathematics from the Univ. of Illinois at Urbana-Champaign. He has received several fellowships and awards including the NSF graduate research fellowship and a Vodafone Foundation fellowship. > >

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Colloquium Speaker Peter Bailis, Today, 12:30pm
by Nicole E. Wagenblast 12 Feb '15

12 Feb '15

Colloquium Speaker Peter Bailis, UC Berkeley Thursday February 12, 12:30pm Computer Science 105 Coordination Avoidance in Distributed Databases The rise of Internet-scale geo-replicated services has led to considerable upheaval in the design of modern data management systems. Namely, given the availability, latency, and throughput penalties associated with classic mechanisms such as serializable transactions, a broad class of systems (e.g., "NoSQL") has sought weaker alternatives that reduce the use of expensive coordination during system operation, often at the cost of application integrity. When can we safely forego the cost of this expensive coordination, and when must we pay the price? In this talk, I will discuss the potential for coordination avoidance -- the use of as little coordination as possible while still ensuring application integrity -- in several modern data-intensive domains. Specifically, I will demonstrate how to leverage the semantic requirements of applications in data serving, transaction processing, and statistical analytics to enable more efficient distributed algorithms and system designs. The prototype systems I have built demonstrate order-of-magnitude speedups compared to their traditional, coordinated counterparts on a variety of tasks, including referential integrity and index maintenance, transaction execution under common isolation models, and asynchronous convex optimization. I will also discuss our experiences studying and optimizing a range of open source applications and systems, which exhibit similar results. Peter Bailis is a Ph.D. candidate at UC Berkeley working in databases and distributed systems. As part of his dissertation work, he has studied and built high performance distributed data management systems for large scale transaction processing, data serving, and statistical analytics in the AMPLab and BOOM projects under the advisement of Joseph M. Hellerstein, Ali Ghodsi, and Ion Stoica. He is the recipient of the NSF Graduate Research Fellowship, the Berkeley Fellowship for Graduate Study, and best-of-conference citations for research appearing in both SIGMOD and VLDB. He received his A.B. in Computer Science from Harvard College in 2011, where he also received the CRA Outstanding Undergraduate Researcher Award.

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Colloquium Speaker Walter Lasecki Tues Feb 17, 12:30pm
by Nicole E. Wagenblast 11 Feb '15

11 Feb '15

Colloquium Speaker Walter S. Lasecki , University of Rochester Tuesday, February 17, 2015 - 12:30pm Computer Science 105 Crowd-Agents: Creating Crowd-Powered Interactive Systems I create and deploy interactive systems that use a combination of human and machine intelligence to operate robustly in real-world settings. Unlike prior work in human computation, my “Crowd Agent” model allows crowds of people to support continuous real-time interactive systems that require ongoing context. For example, Chorus allows multi-session conversations with a virtual personal assistant; Scribe allows non-experts to caption speech in real time for deaf and hard of hearing users, where prior approaches were either not accurate enough, or required professionals with years of training; and Apparition allows designers to rapidly prototype new interactive interfaces from sketches in real time. In this talk, I will describe how computationally-mediated groups of people can solve problems that neither people nor computers can solve alone, and scaffold AI systems using the real-world data they collect. Walter S. Lasecki is a Computer Science Ph.D. candidate at the University of Rochester working with Jeffrey Bigham (CMU) and James Allen (Rochester). He creates interactive intelligent systems that are robust enough to be used in real-world settings by combining both human and machine intelligence to exceed the capabilities of either. Mr. Lasecki received a B.S. in Computer Science and Mathematics from Virginia Tech in 2010, and an M.S. from the University of Rochester in 2011. He was named a Microsoft Research Ph.D. Fellow in 2013, and has held visiting research positions at Stanford and Google[x]. Since 2013, he has been a Visiting Researcher at Carnegie Mellon University.

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