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Events Calendar

Events for February 24, 2014

  • Epstein ISE Department Seminar

    Mon, Feb 24, 2014 @ 03:00 AM - 04:00 PM

    Daniel J. Epstein Department of Industrial and Systems Engineering

    Conferences, Lectures, & Seminars

    Speaker: Dr. John Gunnar Carlsson, Assistant Professor, Department of Industrial and Systems Engineering, University of Minnesota

    Abstract: Geography is a natural factor that must be explicitly considered in many problems in operations research, such as facility location, vehicle routing, and network design. Scientifically speaking, one of the major difficulties that geographic resource allocation problems pose is their interdisciplinary nature; in order to determine an optimal solution to such a problem, one must combine tools from a variety of disciplines, such as mathematical optimization, computational geometry, geometric probability theory, and geospatial analysis. In this talk, we show how to apply these tools to solve two fundamental logistical problems: the first is a high-level analysis of a hub-and-spoke network design problem, and the second is a districting problem in which the goal is to partition a geographic territory so as to balance the workloads of a collection of service facilities or vehicles.

    MONDAY, FEBRUARY 24, 2014
    3:00 - 4:00 PM

    Biography: John Gunnar Carlsson is an assistant professor in the Department of Industrial and Systems Engineering at the University of Minnesota. He received a Ph.D. in computational mathematics from ICME in Stanford University in 2009 and an A.B. in mathematics and music from Harvard College in 2005. He is the recipient of the 2013 INFORMS Computing Society (ICS) Prize, the 2014 Air Force Young Investigator Prize, the 2012 DARPA Young Faculty Award, and the 2010 INFORMS Interactive Session Prize. His research is supported by DARPA, the Office of Naval Research, the Air Force Office of Scientific Research, the National Science Foundation, the Minnesota Department of Transportation (MnDOT), and the Boeing Company, and has appeared in Operations Research, Scientific Reports, Transportation Science, the INFORMS Journal on Computing, and the ACM Transactions on Algorithms.

    Host: Daniel J. Epstein Department of Industrial and Systems Engineering

    More Information: Seminar-Carlsson.doc

    Location: Room 206

    Audiences: Everyone Is Invited

    Posted By: Georgia Lum

  • CS Colloquium: David Chu (Microsoft Research) - Surmounting two challenges of cloud gaming for mobile devices: network latency and server multi-tenancy

    Mon, Feb 24, 2014 @ 11:00 AM - 12:00 PM

    Computer Science

    Conferences, Lectures, & Seminars

    Speaker: David Chu, Microsoft Research

    Talk Title: Surmounting two challenges of cloud gaming for mobile devices: network latency and server multi-tenancy

    Series: CS Colloquium

    Abstract: Gaming on mobile devices is very popular. Cloud gaming such as Sony PlayStation's Now -- where remote servers perform game execution and rendering on behalf of thin clients that simply send input and display output frames -- appears to be well-suited for mobile devices, promising any device the ability to play any game any time. However, cloud gaming must confront network latency and server multi-tenancy. This talk introduces these two challenges, and our two respective solutions, DeLorean and DeeJay.

    For latency, wireless network round trip times (RTTs) often exceed thresholds above which gamers find responsiveness acceptable. We present DeLorean, a speculative execution system for mobile cloud gaming that is able to mask latency. DeLorean produces speculative rendered frames of future possible outcomes, delivering them to the client one entire RTT ahead of time; clients perceive little latency. To achieve this, DeLorean combines: 1) future input prediction; 2) state space subsampling and time shifting; 3) misprediction compensation; and 4) bandwidth compression. This work is a collaboration with the University of Michigan.

    For multi-tenancy, a single server must carefully schedule the GPU across multiple game instances that each have their own real-time latency and throughput requirements. Moreover, it must gracefully handle overload when more clients join than anticipated. We are in the process of building DeeJay, a system that 1) schedules GPU-bound jobs with latency and throughput constraints, and that 2) minimally degrades visual game quality upon system overload.

    To evaluate both DeLorean and DeeJay, we use two high quality, commercially-released games: a twitch-based first person shooter, Doom3, and a role playing game, Fable3.

    Biography: David Chu is a researcher at Microsoft Research in Redmond where he works on mobile systems with an emphasis on mobile gaming. He is also interested in sensing and context for the mobile OS. His work has appeared in The Verge, Engadget and Wired. David received his Ph.D. and M.S. from the University of California, Berkeley, and his B.S. from the University of Virginia.

    Host: Ramesh Govindan

    Location: SAL 222

    Audiences: Everyone Is Invited

    Posted By: Assistant to CS chair

  • Seminars in Biomedical Engineering

    Mon, Feb 24, 2014 @ 12:30 PM - 01:50 PM

    Biomedical Engineering

    Conferences, Lectures, & Seminars

    Speaker: Yuguo Lei, Ph.D., Postdoctoral CIRM Scholar, Postdoctoral Fellow, the David Schaffer Laboratory Department of Chemical Engineering, Bioengineering, and Helen Wills Neuroscience Institute, University of California, Berkeley

    Talk Title: Building Scalable 3D Culture Systems for the Cost-effective Production of Clinical Grade Cells from Human Pluripotent Stem Cells

    Abstract: Building Scalable 3D Culture Systems for the Cost-effective Production of Clinical Grade Cells from Human Pluripotent Stem Cells

    Human pluripotent stem cells (hPSCs), including human embryonic stem cells (hESCs) and induced pluripotent stem cells (iPSCs), have the capacities for indefinite in vitro expansion and differentiation into presumably all cell types in the human body. They therefore represent highly promising cell sources for numerous biomedical applications, such as cell therapy, tissue engineering, drug discovery and toxicity testing. These applications require large numbers of cells of high quality and purity. For instance, ~105 surviving dopaminergic (DA) neurons, ~109 cardiomyocytes, or ~109 β cells are required to treat a patient with Parkinson�s disease (PD), myocardial infarction (MI), or type I diabetes respectively. Analogously, ~1010 hepatocytes are needed for an artificial human liver, and ~1010 cells may be required to screen a million compound library. Considering the large patient populations with degenerative diseases, as well as the millions of chemical/peptide/nucleotide compounds that can be screened against many cell types, massive numbers of hPSCs are thus needed. It is becoming clear that the current 2D-based cell culture systems are incapable of producing sufficient cells with high quality. An attractive approach for scaling up cell production is to move the cell culture from 2D to 3D, and accordingly several 3D suspension systems have been probed for hPSCs production, specifically cell aggregates, cells on microcarriers, and cells in alginate microencapsulates. While these approaches have some attractive aspects, they also highlight significant challenges for 3D hPSC culture including: i) the use of components from human or animal tissue (such as Matrigel, serum, BSA), which limits reproducibility and scalability as well as poses risks for pathogen and immunogen transfer that are problematic for GMP cell production; ii) substantial cell agglomeration that can lead to differentiation and/or death; iii) shear force in agitated cultures that can compromise cell viability; iv) modest cell expansion rates and low cell yields per volume and v) unclear potential for long term serial expansion.

    In this presentation, I will introduce a 3D culture system that utilizes a thermoreversible hydrogel as matrix for versatile and multi-scale hPSC culture. With this simple, defined, scalable, GMP compliant system and protocol that are free of animal derived products, we achieved long-term, high rates of expansion (~20-fold per passage over 5 days, 1072-fold over 280 days, and ~2.0x107 cells/ml gel yield), and high level maintenance of pluripotency (~95%) for multiple hESC and hiPSC lines, all of which offer considerable improvements over the current approaches. Based on this system, we then developed a defined bioprocess for the scalable production of DA neurons from hPSCs for treating PD. We made a small molecule cocktail that can efficiently convert hPSCs into DA progenitors in the 3D hydrogel with a yield of ~8x107 DA progenitors/ml hydrogel and ~80-fold expansion by the end of a 15-day derivation. These cells could survive, mature and function in vivo. I will also present data on using these cells to treat PD in a rodent model. This versatile culture system has the potential to resolve a major challenge that is currently limiting the applications of hPSCs.

    Biography: Dr. Yuguo Lei received his B.S. in chemistry from Peking University in Beijing, China and his M.S. in polymer science at Hong Kong University of Science and Technology, Hong Kong. He then went to UCLA for a M.S. in pharmacology and Ph.D. in chemical engineering before doing his postdoctoral research at UC Berkeley.

    His research interests are to resolve some unsolved human health problems with hPSC-based products. He develops new technologies to address significant challenges that limit the advancement of hPSC-derived cells or products from the benchtop to the bedside. To achieve this goal, he pursues fundamental advances at the intersection of biomaterial design, molecular, cellular and tissue engineering as well as hPSC biology. The resulting technologies are useful for drug discovery, tissue engineering and cell therapies, and Dr. Lei is applying them to treat a number of degenerative diseases, with a focus on the central nervous system.

    Host: David D'Argenio

    Location: 132

    Audiences: Everyone Is Invited

    Posted By: Mischalgrace Diasanta

  • PhD Defense - Sumita Barahmand

    Mon, Feb 24, 2014 @ 01:00 PM - 02:00 PM

    Computer Science

    University Calendar

    Title: Benchmarking Interactive Social Networking Actions

    PhD Candidate: Sumita Barahmand

    Defense Committee: Shahram Ghandeharizadeh (Chair), Ramesh Govindan, Nenad Medvidović and Bhaskar Krishnamachari (Outside Member)

    Date: Monday, February 24, 2014

    Time: 1:00 PM

    Location: EEB 248

    Social networking sites such as Google+, Facebook, Twitter and LinkedIn, are cloud service providers for person to person communications. There are different approaches to building these sites ranging from SQL to NoSQL and NewSQL, Cache Augmented SQL, graph databases and others. Some provide a tabular representation of data while others offer alternative models that scale out. Some may sacrifice strict ACID (Atomicity, Consistency, Isolation, Durability) properties and opt for BASE (Basically Available, Soft-state, Eventual consistency) to enhance performance. Independent of a qualitative discussion of these approaches and their merits, a key question is how do these systems compare with one another quantitatively? This dissertation investigates the viability of a benchmark to address this question.

    Our primary contribution is the design and implementation of a novel benchmark for interactive social networking actions named BG. BG's design decisions are as follows: First, it rates the performance of a system for processing interactive social networking actions by computing two values: Socialites and Social Action Rating (SoAR) using a pre-specified SLA. An example SLA may require 95\% of issued requests to observe a response time faster than 100 milliseconds. Second, BG elevates the amount of unpredictable data produced by a solution to a first class metric, including it as a key component of the SLA (similar to the average response time) and quantifying it as a part of the benchmarking process. It also computes the freshness confidence to characterize the behavior of a weak consistency technique. Third, BG's generated workload is characterized by reads and writes of a very small amount of data from big data. Fourth, BG is a modular, extensible framework that is agnostic to its underlying data store. Fifth, BG employs a logical partitioning of data to scale both vertically and horizontally to thousands of nodes. This is essential for evaluating scalable installations consisting of thousands of nodes. Finally, BG includes a visualization tool to empower an evaluator to monitor an in-progress benchmark and identify bottlenecks.

    BG's possible use cases are diverse. One may use BG to compare and contrast various data stores with one another, characterize tradeoffs associated with alternative physical representations of data, or quantify the behavior of a data store in the presence of various failures (either CP or AP of the CAP theorem) among the others. This dissertation demonstrates use of BG in two contexts. First, to rate an industrial strength relational database management system and a document store, quantifying their performance tradeoffs. This analysis includes the use of a middle tier cache (memcached) and its impact on the performance of each system. Second, to gain insight into alternative design decisions for implementing a social action by characterizing their behavior with different social graphs and system loads. BG's proposed framework is quite novel and opens several new research directions that benefit the systems research community.

    Location: Hughes Aircraft Electrical Engineering Center (EEB) - 248

    Audiences: Everyone Is Invited

    Posted By: Lizsl De Leon

  • Alexander V. Terekhov: Constructing space: how a naive agent can learn spatial relationships by observing sensorimotor contingencies

    Mon, Feb 24, 2014 @ 01:00 PM - 02:30 PM

    Computer Science

    Conferences, Lectures, & Seminars

    Speaker: Alexander V. Terekhov, Laboratory of Psychology of Perception, Paris Descartes University (Paris 5).

    Talk Title: Constructing space: how a naive agent can learn spatial relationships by observing sensorimotor contingencies

    Series: CS Colloquium

    Abstract: The brain sitting inside its bony cavity sends and receives myriads of sensory inputs and outputs. A problem that must be solved either in ontogeny or phylogeny is how to extract the particular characteristics within this "blooming buzzing confusion" that signal the existence and nature of physical space, with structured objects immersed in it, among them the agent's body. The idea that spatial knowledge must be extracted from the sensorimotor flow in order to underlie perception has been considered by a number of thinkers, including Helmholtz, Poincare, Nicod, Gibson, etc. However, little work has considered how this could actually be done by organisms without a priori knowledge of the nature of their sensors and effectors. Here we show how an agent with arbitrary sensors will naturally discover spatial knowledge from the undifferentiated sensorimotor flow. The method first involves tabulating sensorimotor contingencies, that is, the laws linking sensory and motor variables. Second, further laws are created linking these sensorimotor contingencies together. The method works without any prior knowledge about the structure of the agent's sensors, body, or of the world. We show that the extracted laws endow the agent with basic spatial knowledge, manifesting itself through perceptual shape constancy and the ability to do path integration. We further show that the ability of the agent to learn all spatial dimensions depends on the ability to move in all these dimensions, rather than on possessing a sensor that has that dimensionality. This latter result suggests, for example, that three dimensional space can be learned in spite of the fact that the retinas are two-dimensional. We conclude by showing how the acquired spatial knowledge paves the way to building the notion of object.

    Host: Michael Arbib

    Location: HNB 100

    Audiences: Everyone Is Invited

    Posted By: Assistant to CS chair

  • Engineering, Neuroscience & Health (ENR)

    Mon, Feb 24, 2014 @ 04:00 PM - 05:00 PM

    Biomedical Engineering

    Conferences, Lectures, & Seminars

    Speaker: Paola Cesari, University of Verona, Verona, Italy

    Talk Title: Action observation and action imagination: from pathology to the excellent sport performance

    Series: Engineering, Neuroscience & Health (ENH Seminars)

    Biography: http://www.dsnm.univr.it/?ent=persona&id=1611
    Host: Francisco Valero-Cuevas

    More Info: Refreshments will be served from 3.30 to 4 pm.

    Webcast: http://capture.usc.edu/Mediasite/Catalog/Full/946350f1ca8440e7b867e16adba01e4e21/?state=xJE9EJIqlAdw4AAliKf

    Location: Center For Health Professions (CHP) - 147

    WebCast Link: http://capture.usc.edu/Mediasite/Catalog/Full/946350f1ca8440e7b867e16adba01e4e21/?state=xJE9EJIqlAdw4AAliKfp

    Audiences: Everyone Is Invited

    Posted By: Mischalgrace Diasanta

  • USC Investment Office Info Session

    Mon, Feb 24, 2014 @ 05:00 PM - 06:00 PM

    Viterbi School of Engineering Career Services

    Workshops & Infosessions

    Interested in a part-time job or internship in the USC Investment Office? Want to learn more? Attend their Info Session in SGM 101 Monday, February 24, 5-6:00pm. All Viterbi undergrad levels and majors welcome!

    Location: Seeley G. Mudd Building (SGM) - 101

    Audiences: Undergrad

    Posted By: RTH 218 Viterbi Career Services