All Seminars
| Title: Computerized Image Analysis for Biomedical Translational Research |
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| Seminar: Computer Science |
| Speaker: Jun Kong of Emory University |
| Contact: Li Xiong, lxiong@mathcs.emory.edu |
| Date: 2011-10-07 at 3:00PM |
| Venue: MSC W301 |
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| Abstract: Abstract: In biomedical research, availability of an increasing array of high-throughput and high-resolution instruments has given rise to large datasets of "omics" data - such as genomics, proteomics, metabolomics - and imaging data - such as radiology and microscopy imaging. These datasets provide highly detailed views of biological systems and functions. The Emory In Silico Brain Tumor Research Center (EISBTRC), a National Cancer Institute In Silico Research Center of Excellence, has focused on the analysis of Glioblastoma (GBM), a deadly form of brain cancer with a median survival of six months. We are now carrying out large-scale in silico experiments with pubic datasets for Glioblastoma (GBM) brain tumor research for a better understanding of the biological underpinnings that drive the rapid progression of this devastating disease.. In this talk, I will discuss our work on large-scale micro-anatomic feature extraction and integration with genomics and patient survival.\\ \\ Bio:\\ \\ Jun Kong is a research scientist in the Center for Comprehensive Informatics at Emory University. Dr. Kong received his Ph.D. degree in the Dept. of Electrical and Computer Engineering at Ohio State University in 2008. Dr. Kong's research interests include computer vision, statistical machine learning, and medical/microscopy image analysis. He developed Computer-aided Diagnosis (CAD) systems for analyzing a large volume of microscopy images of histologic specimens with intensive use of computer vision and pattern recognition techniques. |
| Title: Turan's problem for odd cycles in pseudorandom graphs |
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| Seminar: Combinatorics |
| Speaker: Mathias Schacht of University of Hamburg |
| Contact: Dwight Duffus, dwight@mathcs.emory.edu |
| Date: 2011-10-07 at 4:00PM |
| Venue: W306 |
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| Abstract: We consider the generalized extremal function $ex(G,F)$, defined to be the largest number of edges that an $F$-free subgraph of $G$ may have. Owing to the work of Mantel, Turan, Erd\"os and Stone this function is well understood for any graph F when $G$ is the complete graph $K_n$. Over the last two decades the problem was investigated and solved when $G$ is the binomial random graph {\bf G(n,p)}. For pseudorandom graphs $G$ only a few results are known. We will discuss recent progress for one of the simplest cases, when F is an odd cycle of fixed length. Roughly speaking, in joint work with Aigner-Horev and Han we obtained almost best possible conditions on the pseudorandom graph $G$ such that $ex(G,C_l)=(1/2+o(1)e(G)$ holds. |
| Title: A characterization of the polarity transform for reflectors |
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| Seminar: Analysis and Differential Geometry |
| Speaker: Anastasia Svishcheva of Emory University |
| Contact: Vladimir Oliker, oliker@mathcs.emory.edu |
| Date: 2011-10-04 at 4:00PM |
| Venue: MSC W301 |
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| Abstract: Convex reflectors arise as solutions to nonlinear second order elliptic partial differential equations (PDE's) of Monge-Amp\`{e}re type expressing conservation laws in geometrical optics. Previously it was shown by V. Oliker that this transform can be viewed as duality with respect to the form $Q(X,Y):=|X||Y|-\langle X, Y \rangle,~X, Y \in \mathbb{R}^{n+1}$. A natural and interesting geometric question is to find a minimal set of properties characterizing such duality transform between reflectors. I will speak about sufficient conditions for this transformation to be such duality. |
| Title: Math in Marriage: Don't Call the Lawyers Yet |
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| EUMMA Event: N/A |
| Speaker: Ron Gould of Emory University |
| Contact: Erin Nagle, erin@mathcs.emory.edu |
| Date: 2011-10-04 at 6:00PM |
| Venue: MSC W301 |
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| Abstract: |
| Title: Evaluating E-Discovery Search |
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| Colloquium: Computer Science |
| Speaker: Douglas W. Oard of University of Maryland |
| Contact: Eugene Agichtein, eugene@mathcs.emory.edu |
| Date: 2011-09-20 at 10:00AM |
| Venue: White Hall 208 |
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| Abstract: Civil litigation in this country relies on each side making relevant evidence available to the other, a process known as "discovery." The explosive growth of information in digital form has led to an increasing focus on how search technology can best be applied to balance costs and responsiveness in what has come to be known as "e-discovery". This is now a multi-billion dollar business, one in which new vendors are entering the market frequently, usually with impressive claims about the efficacy of their products or services. Courts, attorneys, and companies are actively looking to understand what should constitute best practice, both in the design of search technology and in how that technology is employed. In this talk I will provide an overview of the e-discovery process, and then I will use that background to motivate a discussion of which aspects of that process the TREC Legal Track is seeking to model. I will then spend most of the talk describing two novel aspects of evaluation design: (1) recall-focused evaluation in large collections, and (2) modeling an interactive process for "responsive review" with fairly high fidelity. Although I will draw on the results of participating teams to illustrate what we have learned, my principal focus will be on discussing what we presently understand to be the strengths and weaknesses of our evaluation designs.\\ \\ Bio:\\ Douglas Oard is a Professor at the University of Maryland, College Park, with joint appointments in the College of Information Studies and the Institute for Advanced Computer Studies, where he is the director of the Computational Linguistics and Information Processing Lab. Dr. Oard earned his Ph.D. in Electrical Engineering from the University of Maryland, and his research interests center around the use of emerging technologies to support information seeking by end users. His recent work has focused on interactive techniques for cross-language information retrieval, searching conversational media such as speech and email, evaluation design for e-discovery in the TREC Legal Track, and support for sense-making in large digital archival collections. Additional information is available at http://terpconnect.umd.edu/~oard/. |
| Title: Nonnegative Polynomials and Sums of Squares |
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| Seminar: Algebra and Number Theory |
| Speaker: Greg Blehkerman of Georgia Tech |
| Contact: Vicki Powers, vicki@mathcs.emory.edu |
| Date: 2011-09-20 at 3:00PM |
| Venue: MSC E406 |
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| Abstract: A multivariate real polynomial $p$ is nonnegative if $p(x)$ is at least $0$ for all $x \in \mathbb{R}^n$. I will review the history and motivation behind the problem of representing nonnegative polynomials as sums of squares. Such representations are of interest for both theoretical and practical computational reasons. However, much about the relationship between nonnegative polynomials and sums of squares remains unknown. I will present some recent results which establish links between nonnegative polynomials, sums of squares and classical algebraic geometry. In the smallest cases where there exist nonnegative polynomials that are not sums of squares I will describe a complete classification of the differences between these sets. |
| Title: A solution to a problem of determining the sides of a lens |
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| Seminar: Analysis and Differential Geometry |
| Speaker: Hasan Palta of Emory University |
| Contact: Vladimir Oliker, oliker@mathcs.emory.edu |
| Date: 2011-09-20 at 4:00PM |
| Venue: MSC W301 |
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| Abstract: Suppose that a beam of light with the positive vertical direction $\bf{k}$ is crossing a domain $\Omega$ in the horizontal plane $z=0$ with some intensity $I\in L^1(\bar{\Omega})$ and is refracted at both sides of a lens in such a way that the final direction is also $\bf{k}$ and that the beam illuminates a set $T_d$ in the plane $z=d$ with intensity $L\in L^1(\bar{T}_d)$. Let $n_1$ and $n_2$ be the refractive indices of the ambient environment and of the lens, respectively. Such a construction generates a mapping $P:\Omega\to T$ where $T$ is the orthogonal projection of the domain $T_d$ onto $z=0$. We consider the inverse problem of recovering the two sides $z\in C(\bar{\Omega})$ and $w\in C(\bar{T})$ of the lens for given domains $\Omega$ and $T_d$ and the corresponding intensities $I$ and $L$. In analytic formulation, this problem requires a solution to a nonlinear partial differential equation of Monge-Amp\`{e}re type. In this talk, we present a different approach to this problem, describe an algorithm giving approximate solutions using general properties of geometric optics and give some examples. |
| Title: Improving Question-Answering Using Human-Machine Synergies |
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| Seminar: Computer Science |
| Speaker: Ryen White of Microsoft |
| Contact: Eugene Agichtein, eugene@mathcs.emory.edu |
| Date: 2011-09-09 at 3:00PM |
| Venue: MSC W301 |
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| Abstract: Question-and-answer (Q and A) has received significant recent attention with the success of IBM Watson on the quiz show Jeopardy!. Machine-based Q and A is promising, but the technology is some way from rivaling the abilities of humans, even in seemingly rudimentary tasks such as question comprehension and clarification dialog. In this talk, I will argue that by leveraging human-machine synergies, we can create powerful mediated Q and A systems that can overcome the limitations of machine-only solutions, while also meeting basic human desires for interaction with others. Specifically, I will: (1) describe our work on developing IM-an-Expert, a synergistic Q and A system recently shipped by Microsoft Lync; (2) present findings from two studies: one investigating the effect of community size and contact rate on the effectiveness of real-time social Q and A, and another examining the value of predicting outcomes at various points of the question lifecycle, and; (3) provide insights and lessons learned from our deployment of real-time Q and A technology within Microsoft and beyond.\\ \\ Bio:\\ \\ Ryen W. White is a researcher in the Context, Learning, and User Experience for Search (CLUES) Group at Microsoft Research, Redmond. His research interests lie in understanding search interaction and in developing tools to help people search more effectively. He received his Ph.D. in Interactive Information Retrieval from the Department of Computing Science, University of Glasgow, United Kingdom, in 2004. Ryen has published over 100 conference papers and journal articles in Web search, log analysis, and user studies of search systems. He has received five best-paper awards, including two at the ACM SIGIR conference (2007,2010), one at the ACM SIGCHI conference (2011), and one in JASIST (2010). His doctoral research received the British Computer Society’s Distinguished Dissertation Award for the best Computer Science Ph.D. dissertation in the United Kingdom in 2004/2005. Ryen has co-organized numerous workshops on information seeking, in particular exploratory search, including an NSF-sponsored invitational workshop, and has guest co-edited special issues in these areas for a variety of outlets, including Communications of the ACM and IEEE Computer. Since 2008, he has co-organized the annual HCIR workshop. Ryen has served as area chair for many top conferences in information retrieval, and currently serves on the editorial board of ACM TOIS and the Information Retrieval Journal. In addition to academic impact, his research has been shipped in many Microsoft products, including Bing, Xbox, Internet Explorer, and Lync. |
| Title: Mock period functions, sesquiharmonic Maass forms, and non-critical values of L-functions |
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| Seminar: Algebra |
| Speaker: Kathrin Bringmann of University of Cologne |
| Contact: Zachary A. Kent, kent@mathcs.emory.edu |
| Date: 2011-09-06 at 3:00PM |
| Venue: MSC E406 |
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| Abstract: In this talk we view the generating functions of L-functions associated to cusp forms in the framework of automorphic forms. We prove that it can be interpreted as a "mock period function". Further, we show that non-critical values can be encoded into a "sesquiharmonic Maass form". Finally, we formulate and prove an Eichler-Shimura-type isomorphism for the space of mock period functions. |
| Title: Symmetric chain decompositions of quotients of partially ordered sets |
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| Seminar: Combinatorics |
| Speaker: Dwight Duffus of Emory University |
| Contact: Dwight Duffus, dwight@mathcs.emory.edu |
| Date: 2011-09-02 at 4:00PM |
| Venue: W306 |
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| Abstract: Given a subgroup G of the automorphism group of a partially ordered set P, the quotient P/G has as its elements the orbits in P under G with ordering induced by that of P. Canfield and Mason have suggested that for the Boolean lattice of all subsets of a finite set and any subgroup of its automorphism group, these quotients are symmetric chain orders. With Jeremy McKibben-Sanders and Kyle Thayer, we have shown this to be true in some special cases. |