Relations in algebraic complexity

Amir Yehudayoff

Thursday, 31.12.2009, 14:30

Room 337-8 Taub Bld.

On the Limits of Partial Compaction

Anna Bendersky

Wednesday, 30.12.2009, 14:00

Taub 601

Modern software employs dynamic memory allocation to support its memory needs. Allocation and de-allocation of memory create fragmentation: holes between the allocated objects in the memory may be too small to further satisfy future allocation. Fragmentation complicates memory allocation. Furthermore, fragmentation creates a space overhead sometimes making a program crash even though enough memory for allocation is available. Compaction defragments the memory by compacting all objects to the beginning of the memory. However, compaction is ...

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Bioinformatics Forum: Machine learning models for peptide fragmentation

Ari Frank (CS and Engineering, University of California, San Diego)

Wednesday, 30.12.2009, 13:30

Taub 401

Tandem mass spectrometry (MS/MS) has emerged as the tool of choice for high-throughput proteomics analysis. In a typical MS/MS experiment, a protein mixture sample is digested to peptides and is chromatographically separated. Homogenous sets of peptide molecules are then selected by the mass spectrometer and fragmented via collision induced dissociation. The outcome of this process is recorded as a mass spectrum, which is a list of fragment masses and their corresponding intensities. The algorithmic challenge ...

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Theory Seminar: Simple Affine Extractors using Dimension Expansion

Ariel Gabizon (Faculty of Mathematics and Computer Science The Weizmann Institute of Science)

Wednesday, 30.12.2009, 12:30

Taub 201

Let F be the finite field of q elements. An (n,k)-affine extractor is a coloring of F^n with 2 colors, such that every affine subspace of dimension at least k in F^n is colored in a balanced way. Roughly speaking, the problem of explicitly constructing affine extractors gets harder as the field size q gets smaller and easier as k gets larger. In this work, we construct affine extractors whenever q = \Omega( (n/k)^2), provided ...

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Pixel Club Seminar: Video SnapCut: Video Object Cutout in Real Life

Guillermo Sapiro (University of Minnesota)

Wednesday, 30.12.2009, 10:30

Room 337-8 Taub Bld.

We present Video SnapCut, a robust video object cutout system that significantly advances the state-of-the-art. In our system segmentation is achieved by the collaboration of a set of local classifiers, each adaptively integrating multiple local image features. We show how this segmentation paradigm naturally supports local user editing and propagates them across time. The object cutout system is completed with a novel coherent video matting technique. A comprehensive evaluation and comparison is presented, demonstrating the ...

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On the Roles of Computer Science in Systems Biology

Oded Maler

Tuesday, 29.12.2009, 14:30

Room 337-8 Taub Bld.

Pixel Club Seminar: Hyperaccurate Algebraic Fitting Algorithms without Iterations

Prof. Kenichi Kanatani (Computer Science, Okayama University, Okayama, Japan)

Tuesday, 29.12.2009, 11:30

EE Meyer Building 1061

Fitting an algebraic equation to observed data is one of the first steps of many computer vision applications. For example, we fit lines and curves to points in 2D and planes and surfaces in 3D. Computing computing the fundamental matrix or the homography matrix can also be viewed as fitting in a high-dimensional space. A naive way for this is the least squares, also known as ``algebraic distance minimization'', minimizing the sum of squares of ...

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Theory Seminar: The List- Chromatic Number of Graphs Defined on Euclidean Spaces

Peter Komjath (Eotvos University, Budapest)

Monday, 28.12.2009, 14:30

Amado 509

If D is a countable set of positive reals, let X_n(D) be the following graph: the vertices are the points of the n-dimensional Euclidean space, two points joined if their distance is in D. We determine the list-chromatic number of these graphs as much as possible

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DejaView - a Personal Virtual Computer Recorder

Oren Laadan

Monday, 28.12.2009, 11:00

Room 337-8 Taub Bld.

CGGC Seminar: Interpolatory subdivision of sets with applications to reconstruction, of objects from cross-sections

Shai Kels (School of mathematical sciences, Applied math, Tel Aviv Univ.)

Sunday, 27.12.2009, 13:00

Room 337-8 Taub Bld.

We introduce a new geometric definition of affine combinations of two compact subsets of R^n. The 4-point interpolatory subdivision schemes for points is adapted to sets, by first expressing the insertion rule in terms of repeated binary averages, and then replacing these affine combinations of pairs of points by the new affine combinations of sets. This subdivision scheme is applied to the reconstruction of multidimensional objects from cross-sections. We address the questions of convergence and ...

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Key Recovery Attacks of Practical Complexity on AES Variants With Up To 10 Rounds

Orr Dunkelman

Thursday, 24.12.2009, 14:30

Room 337-8 Taub Bld.

Haifux, Haifa Linux Club: Nested x86 Virtualization

Muli Ben-Yehuda (IBM Research - Haifa)

Monday, 21.12.2009, 18:30

Taub 6

Server virtualization has been widely adopted by the market, and the number of servers running virtual machines is increasing daily. As machine virtualization gains popularity, the hypervisor itself, along with its management stack, becomes a basic and required part of the system. The next natural evolution phase in the virtualization abstraction chain is to view the hypervisor as part of the user workload, and to be able to run multiple hypervisors inside virtual machines, each ...

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Bioinformatics Forum: Four-dimensional Realistic Modeling of Pancreatic Organogenesis

Yaki Setty (Computational Biology Group, Computational Science Laboratory Microsoft Research, Cambridge, UK)

Wednesday, 16.12.2009, 13:30

Taub 401

Biological systems are complex, involving feedbacks across numerous processes, mechanisms and objects. Experimental analysis, by its nature, rarely captures the behavior of the complete biological system as it divides the system into static interactions with reduced spatial dimensionality and minimal dynamics. To bridge the gap between experimental findings and the underlying system behavior, we formalize biological findings into mathematically and algorithmically rigorous specifications, which are then compiled into reactive models with an interactive animation. We ...

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Wikipedia-based Semantic Analysis

Shaul Markovitch

Tuesday, 15.12.2009, 14:30

Room 337-8 Taub Bld.

Pixel Club Seminar: Solving SVM and SVM+ with the method of conjugate directions

Dmitry Pechyony (NEC Labs and former CS department Ph.D. graduate)

Thursday, 10.12.2009, 14:30

Room 337-8 Taub Bld.

In learning with privileged information (Vapnik, 2006) the labeled training examples have two views, primary and secondary, and the test examples have only a primary view. The goal of the learner is to leverage the information from these two views in order to build an accurate classifier in the primary view. SVM+ algorithm, introduced by Vapnik, is a major tool for learning with privileged information. Recently Vapnik, Vashist and Pavlovich (2009) showed that by utilizing ...

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Phylogenetic Tree Reconstruction with Insertions and Deletions.

Avinatan Hassidim

Tuesday, 8.12.2009, 14:30

Room 337-8 Taub Bld.

Pixel Club Seminar: Comparative Study of Real-Time Graphics Architectures

Reuven Bakalash (Lucid Technology Ltd.)

Tuesday, 8.12.2009, 11:30

EE Meyer Building 1061

Comparative study of real-time graphics architectures The graphics industry is undergoing dramatic changes. A variety of new graphics pipeline topologies are now emerging, converging between GPUs and multicore-based graphics processors, both leaning on high parallelism and increasing flexibility. The GPUs, based on hardware graphics pipeline, are becoming more flexible by increased programmability, precision and performance, having improved load balance by hundreds of unified shaders, and new geometry and stream-output stages. The many-core graphics architecture, based ...

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Haifux, Haifa Linux Club: 0AD Game - FOSS Strategy Game

Aviv Sharon

Monday, 7.12.2009, 18:30

Taub 6

Aviv Sharon is a contributor to the game, mainly in the graphics area. In addition to the presentation of the game, we hope to establish a reasonably-fast IRC chat with a group of the leading developers of 0AD, on: #0ad on QuakeNet. The purpose of the chat is to refer questions to the leading developers. You are all invited to lurk on the channel, even if you miss the talk...

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Pixel Club Seminar: Using A-Contrario Framework for Object Recognition

Artiom Myaskouvskey (CS, Technion)

Monday, 7.12.2009, 14:30

Taub 601

We describe a new part based detection algorithm. The proposed algorithm uses an empirical model, based on data extracted from the test image to bound the probability that a model candidate arises from a noncategory-related image. The decision is adaptive and does not rely on parameters optimized for possibly unrelated non-category images. Finally, the decision process provides an bound on the number of false alarms in the image. We explain the a-contrario method, derive the ...

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Theory Seminar: Vector Representation
of Graph Domination

Noga Zewi (CS Technion)

Monday, 7.12.2009, 14:30

Amado 509

The famous Hall's marriage theorem from 1935 states that in a bipartite graph with sides M and W, there is a matching of M into W if and only if every subset A of M has at least |A| neighbors in W. A generalization of this theorem for r-partite hypergraphs was proved by Aharoni and Haxell in 2000, using topological methods. In 2005 Aharoni, Berger and Meshulam proved a stronger version of this theorem, using ...

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Pushing the Envelope of Abstraction-based Admissible Heuristics

Carmel Domshlak

Tuesday, 1.12.2009, 14:30

Room 337-8 Taub Bld.

Exact Learning from Random Walk

Iddo Bentov

Wednesday, 25.11.2009, 14:00

Taub 601

The well known learning models in Computational Learning Theory are either adversarial, meaning that the examples are arbitrarily selected by the teacher, or i.i.d., meaning that the teacher generates the examples independently and identically according to a certain distribution. However, it is also quite natural to study learning models in which the teacher generates the examples according to a stochastic process. A particularly simple and natural time-driven process is the random walk stochastic process. We ...

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Theory Seminar: An invariance principle for polytopes

Prahladh Harsha (TIFR, Mumbai, India)

Wednesday, 25.11.2009, 12:30

Taub 201

In this talk, I will talk about a new invariance principle for polytopes (intersection of halfspaces) and some applications of the same. Invariance Principle: Let X be randomly chosen from {−1,1}^n, and let Y be randomly chosen from a spherical Gaussian on R^n. For any polytope P formed by the intersection of k halfspaces, |Pr[X∈P]−Pr[Y∈P]|≤polylog(k)·∆, where ∆ is a parameter that is small for “regular” polytopes. A polytope is said to be regular if for ...

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Pixel Club Seminar: Quaternion Structural Similarity - a new Quality Index for Color Images

Amir Kolaman (EE & CE Ben Gurion)

Tuesday, 24.11.2009, 11:30

EE Meyer Building 1061

Full reference image Quality Index (QI) is an important tool for a cheap and fast assessment of image degradation by different algorithms. A short survey and comparison of recent gray-scale and color image QI is presented. We choose to divide degradation of images into two: luminance changes and saturation changes. From the comparison we see that, in the case of luminance changes, gray scale QI better correlates with Human Visual System (HVS) test results. On ...

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Business Artifacts: A New Foundation for Business Process Modeling

Richard Hull

Tuesday, 17.11.2009, 14:30

Room 337-8 Taub Bld.

Pixel Club Seminar: Geometry and Photometry of Imaging Through a Medium

Tali Treibitz (Electrical Engineering, Technion)

Wednesday, 11.11.2009, 11:30

EE Meyer Building 1061

Images taken through a medium may suffer from poor visibility and loss of contrast. Light passing through undergoes absorption and scattering. Wavelength dependent attenuation causes changes in color and brightness. In addition, light that is scattered back from the medium into the camera (backscatter) veils the object, degrading visibility and contrast. Low signal to noise ratio imposes resolution limits, even if there is no blur. Moreover, refraction between the medium and the camera (in air) ...

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Milestones in Multigrid

Irad Yavneh

Tuesday, 10.11.2009, 14:30

Room 337-8 Taub Bld.

Haifux, Haifa Linux Club: FOSS Philosophy

Orr Dunkelman (CS, Technion)

Monday, 9.11.2009, 18:30

Taub 6

More details

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Pixel Club Seminar: Compressive Imaging Techniques

Yair Rivenson (Electrical & Computer Engineering,
Ben-Gurion University)

Wednesday, 4.11.2009, 13:30

EE Meyer Building 1061

Compressive sensing is a relatively new theory that is based on the fact that many natural signals (or images) can be sparsely represented in some basis. The theory of compressive imaging is applied to directly capture a compressed version of an object's image. Here, we give an overview of different CI techniques, and focus on two that were developed in our group. While implementing conventional CS for imaging we have encountered some practical implementation issues, ...

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Theory Seminar: A groundshaking clash between algebraic and combinatorial geometry

Micha Sharir (Tel-Aviv University)

Wednesday, 4.11.2009, 13:30

Amado building 719

Almost a year ago, Larry Guth and Nets Hawk Katz have obtained the tight upper bound $O(n^{3/2})$ on the number of joints in a set of $n$ lines in 3-space, where a joint is a point incident to at least three non-coplanar lines, thus closing the lid on a problem that has been open for nearly 20 years. While this in itself is a significant development, the groundbreaking nature of their work is the proof ...

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Haifux, Haifa Linux Club: Development Tools

Eli Billauer and Tzafrir Rehan

Wednesday, 4.11.2009, 12:30

Taub 2

Progressing Databases

Gerhard Lakemeyer

Tuesday, 3.11.2009, 14:30

Room 337-8 Taub Bld.

Pixel Club Seminar:Visual Simultaneous Localization and Mapping using Inverse Scaling Parametrization and Uncertain Projective Geometry

Dr. Davide Migliore (CS, Politecnico di Milano)

Tuesday, 27.10.2009, 11:30

EE Meyer Building 1061

One of the principal goals of Computer Vision is to build artificial systems that are able to perceive and understand the world, obtaining information from images acquired by one or more cameras. The same objective, extended to generic sensors, can be found in Robotics, where autonomous robots require a complete knowledge of the environment to provide services and perform tasks as planning, obstacles avoidance or objects grasping. During this talk I will present a novel ...

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Haifux, Haifa Linux Club: Social and Cultural perspective on the Israeli FOSS community

Liora Shlomi (Haifa University)

Monday, 26.10.2009, 18:30

Taub 6

Haifux, Haifa Linux Club: Advanced GDb

David Khosid (Technion and Sandvine)

Monday, 21.9.2009, 18:30

Taub 6

In general, I will be sharing my discovery with you: When the debugging of modern software is required, basic GDB techniques are insufficient, but new techniques can be created from the nearly 160 commands available in GDB. "Modern software" refers to multi- threading, using STL and other libraries, IPC, signals and exception mechanisms. In this lecture, I will explain techniques for debugging large, modern software written in C++. The presentation will be accompanied by vivid ...

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Bioinformatics Forum: Mapping the Interaction Network of the ASPP Family

Hadar Benyamini and Assaf Friedler (The Institute of Chemistry, The Hebrew University of Jerusalem)

Monday, 14.9.2009, 13:00

Biology Auditorium, Technion

The ASPP family proteins have a key role in apoptosis regulation. ASPP1 and ASPP2 promote, while iASPP inhibits p53 mediated apoptosis. ASPP stands for _A_poptosis _S_timulating_P_rotein of _ p_53, as well as representing the domain constitution: _A_nkyrin repeats, _S_H3 and _P_roline rich containing _P_rotein. The ankyrin repeats and SH3 domains (Ank-SH3) mediate the interactions of the ASPP family members with major apoptosis regulators, including p53, Bcl-2 and NFκB. We studied the structure and interactions of ...

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Property Analysis and Automatic Detection of Aspect Categories

Yevgenia Alperina

Wednesday, 9.9.2009, 12:00

Taub 601

This work uses static data and control flow code analysis to aid in proving properties of systems with aspects. Some new categories of aspect advices (code segments) and introduced methods are defined, beyond the existing ones. The categories are chosen considering their effectiveness, in that they both provide real aid in verification of properties, and are automatically detectable using data and control flow. The theoretical part of the thesis investigates which linear temporal logic properties ...

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Haifux, Haifa Linux Club: Introduction to Qt4

Diego Iastrubni (KDE)

Monday, 7.9.2009, 18:30

Taub 6

Why do we need a cross-platform toolkit The qmake build system Strings, list + iterators in Qt4 signals+slots Basic GUI building The purpose of the lecture is not to teach Qt4, but to explain what is available in Qt4 and motivate you to sit on your behind and learn it.

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Pixel Club Seminar: The importance of phase in image processing

Nikolay Skarbnik

Tuesday, 1.9.2009, 11:30

EE Meyer Building 1061

Nikolay Skarbnik Department of Electrical Engineering The Technion Abstract: Signal's phase is a non-trivial quantity. It is therefore often ignored in favor of signal's magnitude. However, phase conveys more information regarding signal structure than magnitude does, especially in the case of images. It is therefore essential to use phase information in various signal/image processing schemes as well as in computer vision. This is true for global phase and, even more so, for local phase. The ...

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Haifux, Haifa Linux Club: FSF Compliance Lab

Yoni Rabkin (Free Software Foundation)

Monday, 31.8.2009, 18:30

Taub 6

We explain the "what", "who" and "how" of the Free Software Foundation GPL Compliance Lab. We go through five sample questions based on real questions the lab received and discuss their answers. We finish with a few words about GPL violations. The lecture is intended for the general audience interested in free software licensing and in particular the licenses published by the FSF.

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CGGC Seminar: Freeform Surfaces for Shape Control in Character Animation

Myung-Soo Kim (School of Computer Science and Engineering, Seoul National University, Seoul, Korea)

Sunday, 30.8.2009, 13:00

Taub 337

CGGC Seminar: Volume transportation for surfaces

Yaron Lipman (Princeton University, USA)

Thursday, 20.8.2009, 14:00

Taub 337

We present a method for automatic surface comparison and alignment based on principles from conformal geometry and optimal mass transportation. One application of the method is efficient calculation of point correspondences between surfaces. Another application is a novel distance definition between disc-type surfaces which forms a tractable alternative to the Gromov-Hausdorff distance. Joint work with I. Daubechies and T. Funkhouser.

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Theory Seminar: A log-space algorithm for planar graph isomorphism

Prajakta Nimbhorkar (The Institute of Mathematical Sciences)

Wednesday, 19.8.2009, 15:00

Room 337-8 Taub Bld.

Graph isomorphism is an important problem and has received lot of attention over several years. Its complexity is still open. There have been polynomial-time algorithms for several subclasses of graphs, including planar graphs. For isomorphism of some of these graph classes, the focus has been on determining the parallel complexity. The goal has been to show the isomorphism problem for various graph classes to be complete for some natural complexity class. For planar graph isomorphism, ...

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Haifux, Haifa Linux Club: Sockets in the Linux Kernel

Rami Rosen

Monday, 17.8.2009, 18:30

Taub 6

We will focus in this lecture about Linux Kernel sockets. Specifically, we will deal with the implementation the following sockets in the Linux kernel: UDP socket. Raw sockets. Unix Domain sockets. Netlink sockets. We will describe the mechanism of sending and receiveing packets with these types of kernel sockets, demonstrating it with short user space applications. We will also deal with Control Messages (aka "ancillary data") and demonstrate retrieving/setting data with Control Messages. We will ...

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Pixel Club Seminar: Relief Analysis and Extraction

Rony Zatzarinni (EE Technion)

Tuesday, 11.8.2009, 11:30

EE Meyer Building 1061

Relief Analysis and Extraction We present an approach for extracting relieves and details from relief surfaces. We consider a relief surface as a surface composed of two components: a base surface and a height function which is defined over this base. However, since the base surface is unknown, the decoupling of these components is a challenge. We show how to estimate a robust height function over the base, without explicitly extracting the base surface. This ...

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Bioinformatics Forum: Detecting Functional Overlapping Genes

Niv Sabath (Biology and Biochemistry, University of Houston, TX )

Monday, 27.7.2009, 10:30

2nd floor Miklat, Biology Build.

As far as protein-coding genes are concerned, there is a non-zero probability that at least one of the five possible overlapping sequences of any gene will contain an open-reading frame (ORF) of a length that may be suitable for coding a functional protein. It is, however, very difficult to determine whether or not such an ORF is functional. We developed a new method that employs evolutionary principles to identify functional overlapping genes based on the ...

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Haifux, Haifa Linux Club: Mesh networking; kernel, netlink and transport layer sockets

Rami Rosen

Sunday, 26.7.2009, 18:30

Taub 6

We will deal in this lecture with Mesh networking, kernel sockets, netlink/rtnelink sockets and transport layer sockets.

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Dimensionality Reduction for 3D Articulated Body Tracking and Human Action Analysis.

Leonid Raskin

Wednesday, 15.7.2009, 10:00

Taub 601

Tracking humans, understanding their actions and interpreting them are crucial to a great variety of applications. Tracking is used in automated surveillance, human-computer interface applications and in security applications. During the last decade extended research has been conducted on this subject. Analysis of human interactions is a complicated and challenging task for several reasons. First, the large number of body parts makes it hard to detect each part separately. Second, differences in things like clothing ...

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Dimensionality Reduction for 3D Articulated Body Tracking and Human Action Analysis.

Leonid Raskin

Wednesday, 15.7.2009, 10:00

Taub 601

Tracking humans, understanding their actions and interpreting them are crucial to a great variety of applications. Tracking is used in automated surveillance, human-computer interface applications and in security applications. During the last decade extended research has been conducted on this subject. Analysis of human interactions is a complicated and challenging task for several reasons. First, the large number of body parts makes it hard to detect each part separately. Second, differences in things like clothing ...

[Full version]

[Full version]

Dimensionality Reduction for 3D Articulated Body Tracking and Human Action Analysis.

Leonid Raskin

Wednesday, 15.7.2009, 10:00

Taub 601

Tracking humans, understanding their actions and interpreting them are crucial to a great variety of applications. Tracking is used in automated surveillance, human-computer interface applications and in security applications. During the last decade extended research has been conducted on this subject. Analysis of human interactions is a complicated and challenging task for several reasons. First, the large number of body parts makes it hard to detect each part separately. Second, differences in things like clothing ...

[Full version]

[Full version]

Dimensionality Reduction for 3D Articulated Body Tracking and Human Action Analysis.

Leonid Raskin

Wednesday, 15.7.2009, 10:00

Taub 601

[Full version]

Dimensionality Reduction for 3D Articulated Body Tracking and Human Action Analysis.

Leonid Raskin

Wednesday, 15.7.2009, 10:00

Taub 601

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Haifux, Haifa Linux Club: Google's Android: An Overview

Yoni Rabkin

Monday, 13.7.2009, 18:30

Taub 6

This lecture is an overview of developing applications for Google's Android. We start by introducing Android and its components, we look at the anatomy of an Android application, we show the basic components of Android application development including UI design and finally we say some things about the development environment. The lecture is for people with no prior knowledge of the Android system as it is only an overview.

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Bioinformatics Forum: Structural Sources of Robustness in Biochemical Reaction Networks

Guy Shinar (Uri Alon's Group, Molecular Cell Biology & Physics of Complex Systems, Weizmann Institute of Science)

Thursday, 9.7.2009, 13:30

Taub 601

Cell-to-cell and temporal variations in the concentrations of biomolecular components are inevitable. These variations in turn propagate along networks of chemical reactions to impart changes in the concentrations of still other species, such as phosphorylated transcription factors, that influence biological activity. Because excessive variations in the levels of certain active molecules might sometimes be deleterious to cell function, regulation systems have evolved that act to maintain concentrations within tight bounds. Although the mechanistic basis of ...

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Pixel Club Seminar: Semantically Linked Instructional Content

Alon Efrat

Tuesday, 30.6.2009

Taub 337

In this talk we will discuss the SLIC project developed at the University of Arizona and IBM Almaden Research center. The SLIC (Semantically Linked Instructional Content ) aims to assist students and scholars efficiently browse and seek segments of interest in educational videos of lectures and talks. In particular, it focuses on lectures that use slides, where the content of the slides file gives valuable hints as to how to break the video into meaningful ...

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Haifux, Haifa Linux Club: KSM and the art of memory mangement

Izik Eidus (Red Hat)

Monday, 29.6.2009, 18:30

Taub 6

KSM is a linux driver that allows dynamically sharing identical memory pages between one or more processes. Unlike traditional page sharing that is made at the allocation of the memory, ksm do it dynamically after the memory was created. Memory is periodically scanned; identical pages are identified and merged. The sharing is unnoticeable by the process that use this memory. (the shared pages are marked as readonly, and in case of write do_wp_page() take care ...

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Randomness - a computational perspective

Avi Wigderson - in memory of Shimon Even

Sunday, 28.6.2009, 16:30

Room 337-8 Taub Tentative Bld.

Theory Seminar: Balanced Allocations: Simplifications and Generalizations

Udi Wieder (Microsoft Research)

Wednesday, 24.6.2009, 15:00

Room 337-8 Taub Bld.

Say we place m balls sequentially into n bins, where each ball is placed by randomly selecting d bins and placing it in the least loaded of them. What is the load of the maximum bin when m>>n? It is well known that when d=1 the maximum load is m/n + \tildeO(sqrt(m/n)), whereas when d>=2 the maximum load is m/n + loglog n. Thus when more than one bin is sampled, the gap between maximum ...

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Pixel Club Seminar: Learning and Multiagent Reasoning for Autonomous Agents

Prof. Peter Stone (CS, The University of Texas at Austin, USA)

Sunday, 21.6.2009, 11:30

Room 337-8 Taub Bld.

One goal of Artificial Intelligence is to enable the creation of robust, fully autonomous agents that can coexist with us in the real world. Such agents will need to be able to learn, both in order to correct and circumvent their inevitable imperfections, and to keep up with a dynamically changing world. They will also need to be able to interact with one another, whether they share common goals, they pursue independent goals, or their ...

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Cluster-Based Computation of Relational Joins

Jeffrey D. Ullman

Thursday, 18.6.2009, 10:30

Room 337-8 Taub Bld.

Theory Seminar: Locally Testable Codes Require Redundant Testers

Michael Viderman (CS, Technion)

Wednesday, 17.6.2009, 15:00

Room 337-8 Taub Bld.

Locally testable codes (LTCs) are error-correcting codes for which membership, in the code, of a given word can be tested by examining it in very few locations. Most known constructions of locally testable codes are linear codes, and give error-correcting codes whose duals have (superlinearly) {\em many} small weight codewords. Examining this feature appears to be one of the promising approaches to proving limitation results for (i.e., upper bounds on the rate of) LTCs. Unfortunately ...

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2-Source Extractors Under Cryptographic Assumptions, and Cryptography with Defective Randomness.

Yael Tauman Kalai

Tuesday, 16.6.2009, 14:30

Room 337-8 Taub Bld.

Pixel Club Seminar: Compression of facial images using sparse and redundant representations and the K-SVD algorithm

Ori Bryt (EE, Technion)

Tuesday, 16.6.2009, 11:30

EE Meyer Building 1061

Compression of facial images using sparse and redundant representations and the K-SVD algorithm

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Haifux, Haifa Linux Club: Arduino - Open Source Hardware and a Viewport to Micro Manufacturing

Amy Chayun

Monday, 15.6.2009, 18:30

Taub 6

Arduino is an open source hardware platform. Since its launch it became much more than just a hobbyist playground. This presentation will introduce the Arduino platform, go over some of the messy details and explore its potential to the casual hacker. No electric engineering background is needed, some basic C knowledge is assumed.

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Theory Seminar: Identity Testing, Isolation and Lower Bounds

Partha Mukhopadhyay (CS, Technion)

Wednesday, 10.6.2009, 15:00

Taub 337

Using ideas from automata theory we design a new efficient (deterministic) identity test for the noncommutative polynomial identity testing problem. More precisely, given as input a noncommutative circuit C computing a polynomial of degree d in the noncommutative ring F{x_1,x_2,...,x_n} with at most t monomials, where the variables x_i are noncommuting, we give a deterministic polynomial identity test that checks if C=0 and runs in time polynomial in d, n, size(C), and t. Prior to ...

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Theory Seminar: Rank minimization via the gamma_2 norm

Troy Lee (Columbia University)

Sunday, 7.6.2009, 14:30

Room 337-8 Taub Bld.

In the affine rank minimization problem, the goal is to minimize the rank of a matrix subject to a set of affine constraints. This is in general an NP-hard problem. We study a convex relaxation of this problem where the rank objective function is replaced by the gamma_2 norm. The gamma_2 norm can be viewed as a weighted version of the trace norm and can be expressed as a semidefinite program. We show that, given ...

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Theory Seminar: Lower Bounds for Testing Triangle-freeness in Boolean functions

Arnab Bhattacharyya, (MIT)

Wednesday, 3.6.2009, 15:00

Room 337-8 Taub Bld.

Let f_{1},f_{2}, f_{3} : F_2^n -> {0,1} be three Boolean functions. We say a triple (x,y,x+y) is a triangle in the function triple (f_{1}, f_{2}, f_{3}) if f_{1}(x)=f_{2 (y)=f_{3}(x+y)= 1. (f_{1}, f_{2}, f_{3}) is said to be triangle-free if there is no triangle among the three functions. The distance between a function triple and triangle-free functions is the minimum fraction of the function values one needs to modify in order to make the function triple ...

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CGGC Seminar: Bezier and B-spline curves with knots in the complex plane

Ron Goldman (Computer Science, Rice University)

Wednesday, 3.6.2009, 11:00

Room 337-8 Taub Bld.

Haifux, Haifa Linux Club: Compiling Effectively for Cell with GCC

Revital Eres (IBM HRL)

Monday, 1.6.2009, 18:30

Taub 6

In this talk I describe several techniques that we developed to support the generation of high quality code for the Cell Broadband Engine, addressing some of its key challenges and advantages. The architecture of the Cell Broadband Engine developed jointly by Sony, Toshiba, and IBM, represents a new direction in processor design. In addition to a PowerPC-compatible Power Processor Element (PPE) the Cell architecture features an array of eight Synergistic Processor Elements (SPEs) supporting a ...

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Discrete Geometric Algorithms for Mesh Processing

Mirela Ben-Chen

Monday, 1.6.2009, 10:30

Taub 337

Geometric modeling deals with representing real objects in a virtual world. A popular geometric representation is the polygonal model. For many applications the need arises to improve the model while preserving its intrinsic geometric property, that it still describes the same "real" object. In this talk, we present a few applications, which although are quite different, use similar geometric concepts and mathematical machinery, the most noticeable being the notion of conformality as a change to ...

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Haifux, Haifa Linux Club: OpenCL Overview

Ofer Rosenberg (Intel)

Monday, 25.5.2009, 18:30

Taub 6

OpenCL is the first Cross-Architecture, Cross-OS, open standard for parallel computing on heterogeneous systems. It targets GPU's, CPU's, and other processing devices (like DSP's and Accelerators), providing a uniform programming model of the system. OpenCL is designed to support a wide range of usages, from GPGPU GFX usages (like Physics) to High Performance Computing. This introduction will present OpenCL Programming Model (platform, memory, compilation, etc.) & the OpenCL C Language (an extension of ANSI C).

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CGGC Seminar: An algorithm for computing Voronoi diagrams of general generators in general spaces

Daniel Reem (Mathematics, Technion)

Sunday, 24.5.2009, 13:00

Taub 401 (note special room)

Voronoi diagrams appear in many areas in science and technology and have diverse applications. Roughly speaking, they are a certain decomposition of a given space into cells, induced by a distance function and by a tuple of subsets called the generators or the sites. Voronoi diagrams have been the subject of extensive research during the last 35 years, and many algorithms for computing them have been published. However, these algorithms are for specific cases. They ...

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The Birth of Model Checking

Prof. Edmund Clarke

Thursday, 21.5.2009, 14:30

Room 337-8 Taub Bld.

Pixel Club Seminar: Puzzle-like Collage

Stas Goferman (EE, Technion)

Thursday, 21.5.2009, 11:30

EE Meyer Building 1061

Collages have been a common form of artistic expression since their first appearance in China around 200 BC. Recently, with the advance of digital cameras and digital image editing tools, collages have gained popularity also as a summarization tool. We propose an approach for automating collage construction, which is based on assembling exact cutouts of salient regions in a puzzle-like manner. We show that this approach produces collages that are informative, compact, and eye-pleasing. To ...

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Haifux, Haifa Linux Club: gdb - Customize it the Way You Want

Guy Keren

Monday, 18.5.2009, 18:30

Taub 601

gdb is one of the more powerful tools that you have as a programmer in the UNIX environment. This talk is an introduction to gdb and how to make it work for you. This is the second part of a 2-meetings set . In the 1st meeting we have covered everything up to the section titled 'Where Have My Source Files Gone?' in the slides. In the second meeting we'll go over the rest (writing ...

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Theory Seminar: Affine Dispersers from Subspace Polynomials

Eli Ben-Sasson (Computer Science, Technion)

Wednesday, 13.5.2009, 15:00

Room 337-8 Taub Bld.

An affine disperser over a field F for sources of dimension d is a function f: F^n -> F that is nonconstant (i.e., takes more than one value) on inputs coming from a d-dimensional affine subspace of F^n. Affine dispersers have been considered in the context of deterministic extraction of randomness from structured sources of imperfect randomness, and in particular, generalize the notion of dispersers for bit-fixing sources. Previously, explicit constructions of affine dispersers were ...

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Concurrent Non-commutative Boosted Transactions

Maurice Herlihy

Tuesday, 12.5.2009, 14:30

Room 337-8 Taub Bld.

Pixel Club Seminar: Illuminating Cameras

Srinivasa Narasimhan (Robotics Institute Carnegie Mellon University)

Tuesday, 12.5.2009, 11:30

EE Meyer Building 1061

Light sources and cameras are optical duals: sources emit light rays while the cameras capture them. This talk will argue that light sources can serve as better cameras in many applications, advancing the state of the art in computer vision. (a) By moving a light source instead of a camera, we show how to reconstruct highly intricate shapes like wreaths, corals and tree branches from hundreds of 'views'. (b) We leverage the 'illumination dithering' in ...

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Exo-leasing: Escrow Synchronization for Clients of Commodity Storage Servers

Liuba Shrira

Sunday, 10.5.2009, 14:30

Room 337-8 Taub Bld.

Bioinformatics Forum: Translation efficiency in human healthy and cancerous cells and the universal translation efficiency profile of proteins

Tamir Tuller (School of Computer Science & Department of Molecular Microbiology and Biotechnology, Tel-Aviv University)

Thursday, 7.5.2009, 13:30

Taub 601

Translation Efficiency (TE) is a basic process of favoring codons with higher levels of tRNAs. In this talk, I will survey three recent results that are related to studying TE from a computational/systems biological aspect: a) TE in humans is efficient: It is believed that in many unicellular organisms codon bias has evolved to optimize TE. Previous studies, however, have left the question of TE in humans an intriguingly open one. We perform the first ...

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Theory Seminar: List-decoding for Reed-Muller Codes

Shachar Lovett (Weizmann Institute of Science)

Wednesday, 6.5.2009, 15:00

Taub 337

The widely held belief that BQP strictly contains BPP raises fundamental questions: Upcoming generations of quantum computers might already be too large to be simulated classically. Is it possible to experimentally test that these systems perform as they should, if we cannot efficiently compute predictions for their behavior? Vazirani has asked [Vaz07]: If computing predictions for Quantum Mechanics requires exponential resources, is Quantum Mechanics a falsifiable theory? In cryptographic settings, an untrusted future company wants ...

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Scheduling of Wireless Networks

Magnus Halldorsson

Tuesday, 5.5.2009, 14:30

Room 337-8 Taub Bld.

Haifux, Linux Haifa Club: gdb in Greater Depth

Guy Keren

Monday, 4.5.2009, 18:30

Taub 6

Theory Seminar: Interactive Proofs For Quantum Computations

Elad Eban (Hebrew University)

Wednesday, 22.4.2009, 15:30

Taub 337

The widely held belief that BQP strictly contains BPP raises fundamental questions: Upcoming generations of quantum computers might already be too large to be simulated classically. Is it possible to experimentally test that these systems perform as they should, if we cannot efficiently compute predictions for their behavior? Vazirani has asked [Vaz07]: If computing predictions for Quantum Mechanics requires exponential resources, is Quantum Mechanics a falsifiable theory? In cryptographic settings, an untrusted future company wants ...

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Bioinformatics Forum: Alignment of Trees and Directed Acyclic Graphs in Computational Biology

Gabriel Valiente (Technical University of Catalonia, the University of the Balearic Islands, and the Centre for Genomic Regulation, Barcelona)

Wednesday, 22.4.2009, 13:30

Taub 701

Bioinformatics Forum: It is well known that the string edit distance and the alignment of strings coincide, while the alignment of trees differs from the tree edit distance. In this talk, we recall various constraints on directed acyclic graphs that allow for a unique (up to isomorphism) representation, called the path multiplicity representation, and present a new method for the alignment of trees and directed acyclic graphs that exploits the path multiplicity representation to produce ...

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Web Mining or The Wisdom of the Crowds

Ricardo Baeza-Yates

Thursday, 2.4.2009, 14:30

Room 337-8 Taub Bld.

Bioinformatics Forum: Evolutionary universals and the nature of genome evolution

Eugene V. Koonin (National Center for Biotechnology Information, NLM, NIH, USA)

Thursday, 2.4.2009, 13:30

Taub 601

Comparative genomics and systems biology reveal several surprising universals of genome evolution such as the distribution of evolution rates across genes, the distribution of paralogous gene family size, and connections between expression and evolution rate. The existence of these universals calls for simple, general models of evolutionary processes akin to those used in statistical physics (eg, birth and death processes), and at least in some cases, such models seem to explain the observed universal patterns. ...

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Pixel Club Seminar: The Norm-Product Algorithm: Convergent Message-Passing for LP-relaxation and Approximate Inference

Tamir Hazan (School of Engineering and Computer Science
The Hebrew University of Jerusalem)

Tuesday, 31.3.2009, 11:30

EE Meyer Building 1061

We derive a one-parameter local message-passing algorithm, called "norm-product", which covers both the tasks of computing approximate marginal probabilities and maximum a posteriori (MAP) assignment for general graphical models. A parameter $\epsilon$ controls a perturbation term of a "fractional entropy approximation" $\tilde H$ which includes Bethe, Tree-reweighted (TRW) and convex entropy approximations. When $\tilde H$ is the Bethe approximation, the settings $\epsilon=0$ and $\epsilon=1$ produce the max-product and sum-product algorithms, respectively. When $\tilde H$ is ...

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Haifux, Linux Haifa Club: OpenMp Usage

Orna Agmon Ben-Yehuda (CS, Technion)

Monday, 30.3.2009, 18:30

Taub 6

OpenMp is a standard for shared memory parallelization of Fortran and c/c++. gcc 4.2 implements this standard in the gomp library. In the previous lecture we have reviewed some of the basic constructs. In this talk we will discuss the way to approach the task of using openMP in legacy code, and address some common implementation dilemmas the programmer is bound to hit.

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Theory Seminar: 2-query PCP Composition

Prahladh Harsha (UT Austin & Technion)

Wednesday, 25.3.2009, 15:00

Taub 701

In a recent breakthrough, Moshkovitz and Raz [MR] proved that NP can be verified using two queries, sub-constant error, and nearly linear proof length. The main technical component of their result is a new composition theorem for certain specific 2-query PCPs. All earlier composition theorems suffered from incurring an additional query per composition. We abstract their proof and prove a generic 2-query PCP composition theorem with low error. More formally, we define a certain (natural) ...

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Bioinformatics Forum: Towards a cognitive robotic biologist: machine learning for automated image
analysis in systems biology

Leon Peshkin (Systems Biology, Harvard Medical School, MA, USA)

Wednesday, 25.3.2009, 14:30

Shelter room, Biology Department, Technion

Fluorescent microscopy imaging has become one of the main tools of biological research. Most wet labs collect Gigabytes of images every day. The resulting data is almost exclusively annotated and analyzed by hand. Such data contains a wealth of information potentially relevant to a variety of research questions. Yet, due to the labor-intensive nature of data analysis and huge volume, the precious data is discarded without a chance to realize its full scientific value. A ...

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Quantum channels and their multiple capacities

Charles H. Bennett

Tuesday, 24.3.2009, 14:30

Room 337-8 Taub Bld.

Pixel Club Seminar: Fast Mean Shift via KDE Reduction

Daniel Freedman (HP Labs)

Tuesday, 24.3.2009, 11:30

EE Meyer Building 1061

The Mean Shift procedure is a well established clustering technique that is widely used in imaging applications such as image and video segmentation, denoising, object tracking, texture classification, and others. However, the Mean Shift procedure has relatively high time complexity which is superlinear in the number of data points. In this paper we present a novel fast Mean Shift procedure which is based on the random sampling of the Kernel Density Estimate (KDE). We show ...

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Polynomial time algorithms for clustering and image segmentation problems

Dorit S. Hochbaum

Sunday, 22.3.2009, 14:30

Room 337-8 Taub Bld.

Bioinformatics Forum: Cell-Signaling Dynamics in Time and Space

Boris N. Kholodenko (Systems Biology Institute, University College Dublin, Ireland)

Thursday, 19.3.2009, 14:30

Taub 601

Extracellular information received by plasma membrane receptors is encoded into complex temporal and spatial patterns of phosphorylation and topological relocation of signaling proteins. Integration of this information by protein kinase cascades creates the spatio-temporal code that confers signaling specificity and leads to important decisions that determine cell’s fate. Aberrant processing of signalling information is a leading cause of many human diseases that range from developmental defects to cancer, chronic inflammatory syndromes and diabetes. We employ ...

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Theory Seminar: 3-Query Locally Decodable Codes of Subexponential Length

Klim Efremenko, Weizmann Institute

Wednesday, 18.3.2009, 18:30

Room 337-8 Taub Bld.

Locally Decodable Codes (LDC) allow one to decode any particular symbol of the input message by making a constant number of queries to a codeword, even if a constant fraction of the codeword is damaged. In a recent work ~\cite{Yekhanin08} Yekhanin constructs a $3$-query LDC with sub-exponential length of size $\exp(\exp(O(\frac{\log n}{\log\log n})))$. However, this construction requires a conjecture that there are infinitely many Mersenne primes. In this paper we give the first unconditional constant ...

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Translation validation: from Simulink to C.

Michael Riabzev

Wednesday, 18.3.2009, 14:00

Taub 601

Translation validation is a technique for formally establishing the semantic equivalence of a source and a target of a code generator/compiler. In this work we present a translation validation tool for the Real-Time Workshop code generator that receives as input Simulink models and generates optimized C code. The lecture will begin with a demonstration of the Simulink models format and automatically generated C code. It will then focus on the verification condition that is required ...

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Haifux, Linux Haifa Club: Introduction to openmp

Orna Agmon Ben-Yehuda (CS, Technion)

Monday, 16.3.2009, 18:30

Taub 6

Bioinformatics Forum: Using Computational Tools for Piecing Together Small Trees into the Large Tree of Life

Sagi Snir (Institute of Evolution, Haifa University)

Thursday, 12.3.2009, 13:30

Taub 601

Bioinformatics Forum: The reconstruction of evolutionary trees (also known as “phylogenies”) is central to many problems in Biology. With the massive amounts of molecular data being produced, attention has increasingly turned to phylogenetic analyses of larger datasets, containing several hundreds to several thousand nucleotide sequences. Accordingly, a new program, “Assembling the Tree of Life”, has set the goal of producing a highly accurate estimate of the evolutionary history of all life on earth. Key to ...

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Compressed Sensing Meets Information Theory

Dror Baron

Thursday, 5.3.2009, 14:30

Room 337-8 Taub Bld.

The Theory-Practice Interplay in Machine Learning - Emerging Theoretical Challenges

Shai Ben-David

Tuesday, 3.3.2009, 14:30

Room 337-8 Taub Bld.

Theory Seminar: New Direct Product Code Testers, and PCPs

Avi Wigderson (IAS)

Sunday, 1.3.2009, 11:30

TBA

The direct product code encodes the truth table of a function f:U-->R by a function f^k:U^k -->R^k, which lists the value of f in all k-tuples of inputs. We study its (approximate) proximity testing to this code in the "list decoding" regime. We give a 3-query tester for distance 1-exp(-k) (which is impossible with 2 queries). We also give a 2-query tester for distance 1-1/poly(k) for a derandomized version of this code (of polynomial rate). ...

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Haifux, Linux Haifa Club: Improving Linux Environment

Shahar Dag (CS, Techniono)

Thursday, 19.2.2009, 13:00

SSDL Laboratory, Taub Build., Floor 2

LINUX EVENT: We will discuss the ways to promote the use in Linux among students and to improve the SSDL service. Prof. Yossi Gil will give a talk titled: "How to avoid in Linux programming".

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Pixel Club Seminar: Removal of Turbulence Disturbance in a Movie Scene for Static and Moving Camera, Enabling Vision Applications

Tomer Avidor (Rafael)

Tuesday, 17.2.2009, 11:30

EE Meyer Building 1061

The common method of reconstructing a turbulence scene is through the creation of an artificial reference image. The reference image is usually obtained by averaging video through time. Using optical flow from that reference image to input images would give rise to such applications as: super-resolution, tracking and so forth. However this technique suffers from several drawbacks: the resulting artificial reference frame is blurred, so calculated optical-flow fields are not precise and inhibit the results ...

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Haifux, Linux Haifa Club: Wireless in Linux

Rami Rosen

Monday, 16.2.2009, 18:30

Taub 6

This lecture is a sequel to the Linux Kernel Networking lecture, Advanced Linux Kernel Networking - Neighboring Subsystem; IPSec and IPv6 in the Linux Kernel (Advanced Linux Kernel Networking). - Short history of Linux Wireless : fullmac and softmac. - Wireless Modes of operation: infrastructure mode, independent mode (IBSS), and more. - The Linux Wireless stack (mac80211). - MLME (the management layer). - MLME operations: scanning, association. - RFmon. (monitor mode) and sniffing. - short ...

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Theory Seminar: Rounding Parallel Repetitions of Unique Games

Enav Weinreb (CS, Technion)

Sunday, 15.2.2009, 12:00

Taub 601

We consider the following question: given a two-argument boolean function $f$, represented as an $N\times N$ binary matrix, how hard is to determine the (deterministic) communication complexity of $f$? We address two aspects of this question. On the computational side, we prove that, under appropriate cryptographic assumptions (such as the intractability of factoring), the deterministic communication complexity of $f$ is hard to approximate to within some constant. Under stronger (yet arguably reasonable) assumptions, we obtains ...

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[Full version]

Modeling and Simulation of Stochastic Natural Systems

Azi Lipshtat

Thursday, 12.2.2009, 14:30

Room 337-8 Taub Bld.

Pixel Club Seminar: Blind Separation of Time/Position Varying Mixtures

Ran Kaftory

Thursday, 12.2.2009, 11:30

EE Meyer Building 1061

We address the open engineering problem of blind separation of time/position varying mixtures. We show that there exists a large family of such mixtures that are separable without having prior information about the sources or the mixing system. Unlike studies concerned with instantaneous or convolutive mixtures, we relax the very-restrictive, widely-used, constraint of stationary in time and position, and deal with the more practical and difficult problem of a mixing system (medium) that is varying ...

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CGGC Seminar: An algorithm for the computation of the metric average of two simple polygons

Shay Kels (Mathematics, Tel Aviv University)

Sunday, 8.2.2009, 13:00

Taub 337

In this talk we present an algorithm that applies segment Voronoi diagrams and planar arrangements to the computation of the metric average of two simple polygons. The algorithm is relevant to approximation of set-valued functions. We describe the implementation of the algorithm and present a collection of computational examples. Based on the computational framework of the algorithm, the connectedness of the metric average of two simple polygons is studied. Finally, we extend the algorithm to ...

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Theory Seminar: Rounding Parallel Repetitions of Unique Games

Ishai Haviv (Tel Aviv University)

Sunday, 8.2.2009, 12:00

Taub 601

We show a connection between the semi-definite relaxation of unique games and their behavior under parallel repetition. Specifically, denoting by val(G) the value of a two-prover unique game G, and by sdpval(G) the value of a natural semi-definite program to approximate val(G), we prove that for every large enough $\ell$, if sdpval(G) is at least $1-\delta$, then the value of the $\ell$-times parallel repeated version of G is at least $sdpval(G)^{s \ell}$ where $s=O(\log(k/\delta))$ for ...

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Pixel Club Seminar: Geometry by Deflaring

Fima Koreban (EE, Technion)

Tuesday, 3.2.2009, 11:30

EE Meyer Building 1061

Stray light reflected by lens surfaces creates flare which affects the image. A pronounced form of this flare is aperture ghosting, where bright spots that resemble the shape of the lens aperture are overlayed on the image. This might disrupt image analysis. It occurs when a bright narrow source (usually the Sun) is in the vicinity of the field of view, though often the source may be outside the actual viewed field. This paper analyzes ...

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Haifux, Linux Haifa Club: Sifting a Haystack -- The Slashdot Back-End From a Naive User's Point of View

Tim Lord (Slashdot)

Monday, 2.2.2009, 18:30

Taub 6

I'll give an overview of the Slashdot editorial process, and demonstrate the back-end tools (all running on Linux, mostly written in Perl, with an increasingly Ajax-based user interface) that we use to organize hundreds of submissions each day to select the handful that we post to the page. I'll also explain some of the software-based methods we use to identify and avoid abusive users, and answer any questions that I can.

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CGGC Seminar: View-dependent texture projection mapping in urban scenes

Amit Ben-David (Industrial Engineering, Technion)

Sunday, 1.2.2009, 13:00

Taub 337

View-Dependent Texture Projection Mapping (VDTPM) is a technique used to render a photorealistic novel view of a scene based on a number of aerial photographs of the scene and an authentic 3D model of the scene. Unlike traditional texture mapping, where the texture is "pasted" on the 3D polygons, here the texture is placed on the object using texture projection. Texture projection is a technique which uses the camera model of the photograph to create ...

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Bioinformatics Forum: Towards Optimal Distance Functions for Stochastic Substitutions Models

Shlomo Moran (Computer Science, Technion)

Thursday, 29.1.2009, 14:30

Taub 601

Distance based reconstruction methods of phylogenetic trees are split into two independent parts: first, inter-species distances are inferred using some stochastic model of sequence evolution; then the inferred distances are used to construct a tree. Most research in this area focuses on the second task. This talk concentrates on the task of inter-species distance estimation, and provides a general characterization of distance functions for stochastic substitution models. Then it will be shown that by a ...

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[Full version]

Universal Kernel-Based Learning with Applications to Regular Languages

Aryeh Kontorovich POSTPONED FROM 20/1/09

Thursday, 29.1.2009, 14:30

Room 337-8 Taub Bld.

Theory Seminar: Unique Games with Entangled Provers are Easy

Oded Regev (Tel Aviv University)

Sunday, 25.1.2009, 12:00

Taub 601

We consider one-round games between a classical verifier and two provers who share entanglement. We show that when the constraints enforced by the verifier are `unique' constraints (i.e., permutations), the value of the game can be well approximated by a semidefinite program. Essentially the only algorithm known previously was for the special case of binary answers, as follows from the work of Tsirelson in 1980. Among other things, our result implies that the variant of ...

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[Full version]

Cryptography in Constant Parallel Time and its Applications

Benny Applebaum

Thursday, 22.1.2009, 14:30

Room 337-8 Taub Bld.

Haifux, Linux Haifa Club: Windows Refund HOWTO

Zvi Devir (Computer Science, Technion)

Monday, 19.1.2009, 18:30

Taub 6

Microsoft's End User License Agreement (EULA) allows customers to return unused copied of the Windows operation system to the manufacturer, for a refund or credit. Not surprisingly, the laptop manufacturers are not too happy with that, and they raise obstacles on customers who would like to get a refund. In this lecture I will talk about the first successful Windows Vista refund case in Israel.

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Content Identification

Yacov Yacobi

Sunday, 18.1.2009, 14:30

Room 337-8 Taub Bld.

CGGC Seminar: Algorithms for Heilbronn's triangle problem

Osnat Tal (Computer Science, Technion)

Sunday, 18.1.2009, 13:00

Room 337-8 Taub Bld.

The classic Heilbronn's triangle problem is to maximize the area of the smallest of the $\binom{n}{3}$ triangles determined by $n$ points in the unit square. One aspect of the problem is finding the optimal locations of the points. Another issue is finding lower and upper bounds on the smallest triangle's area in the optimal configuration(s) of points. With respect to the first aspect, mathematicians and computer scientists have worked in the last decades to find ...

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Theory Seminar: The inverse conjecture for the Gowers norm over finite fields

Tamar Ziegler (Mathematics, Technion)

Sunday, 18.1.2009, 12:00

Taub 601

The Gowers uniformity norms U_k measure a certain kind of psuedo randomness. For example, a function f on a finite (large) dimensional vector space V over a finite field F has small U_2 norm if and only if all its Fourier coefficients are small - i.e it has no significant correlation with linear phase functions. The content of the inverse conjecture for the Gowers norms is that a similar relation exists between the U_k norms ...

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An Online Multi-unit Auction for Perishable Goods with Unknown Supply

Sourav Chakraborty

Tuesday, 13.1.2009, 14:30

Room 337-8 Taub Bld.

Pixel Club Seminar: What is a Good Image Segment? A Unified Approach to Segment Extraction

Shai Bagon (The Weizmann Institute of Science)

Tuesday, 13.1.2009, 11:30

EE Meyer Building 1061

There is a huge diversity of definitions of "visually meaningful" image segments, ranging from simple uniformly colored segments, textured segments, through symmetric patterns, and up to complex semantically meaningful objects. This diversity has led to a wide range of different approaches for image segmentation. We present a single unified framework for addressing this problem - "Segmentation by Composition". We define a good image segment as one which can be easily composed using its own pieces, ...

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Event Processing - the next generation

Opher Etzion

Sunday, 11.1.2009, 14:30

Room 337-8 Taub Bld.

Theory Seminar: Finding Significant Fourier Transform Coefficients

Adi Akavia (IAS/DIMACS)

Sunday, 11.1.2009, 12:00

Room 337-8 Taub Bld.

Computing the Fourier transform is a basic building block used in numerous applications. For data intensive applications, even the O(N log N) running time of the Fast Fourier Transform (FFT) algorithm may be too slow, and sub-linear running time is necessary. Clearly, outputting the entire Fourier transform in sub-linear time is infeasible, nevertheless, in many applications it suffices to find only the \tau-significant Fourier transform coefficients, that is, the Fourier coefficients whose magnitude is at ...

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Preconditioners for Saddle Point Linear Systems

Chen Greif

Thursday, 8.1.2009, 14:30

Room 337-8 Taub Bld.

TODAY - Bioinformatics Forum: Reverse Ecology: From Large-Scale Analysis of Metabolic Networks, Growth Environments and
Seed Sets to Species Interaction and Metagenomics

Elhanan Borenstein (Stanford University & Santa Fe Institute)

Thursday, 8.1.2009, 13:30

Taub 601

The topology of metabolic networks may provide important insights not only into the metabolic capacity of species, but also into the habitats in which they evolved. In this talk I will present several analyses of metabolic networks and show how various ecological insights can be obtained from genomic-based data. I will first introduce various environmental and genetic factors that affect the structure of metabolic networks. I will then present the first large-scale computational reconstruction of ...

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Computing structural changes in proteins

Nurit Haspel

Tuesday, 6.1.2009, 14:30

Room 337-8 Taub Bld.

Pixel Club Seminar: Unsupervised organization of image collections: taxonomies and beyond

Evgeniy Bart (Computational Vision Lab, California Institute of Technology)

Tuesday, 6.1.2009, 11:30

EE Meyer Building 1061

Organizing images is crucial for dealing efficiently with large image collections. In this talk, I will explore approaches to such an organization and its benefits. I introduce a non-parametric Bayesian model called TAX (similar to NCRP), which can organize images into a tree-shaped taxonomy in an unsupervised manner. The main conclusions are: (a) images can be organized automatically, in a completely unsupervised manner; (b) this organization is intuitively appealing, and helps represent and interpret images ...

[Full version]

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Haifux, Linux Haifa Club: Supercomputing 2008

Orna Agmon

Monday, 5.1.2009, 18:30

Taub 6

Haifux, Linux Haifa Club: Linux Hardware

Cathy Malmrose

Sunday, 4.1.2009, 18:30

Taub 6

Building hardware to run a Linux distro used to be quite tricky, involving plenty of trial and error with components while filing bug reports in various places. In the last year, hardware has reached the point where it is easier to build a Linux system that just works. Cathy Malmrose, a Linux hardware builder from Berkeley, California, US will share what she has learned from various OEMs and will give a broad view of how ...

[Full version]

[Full version]

How To Scrub iPhone Blenders: Machine Learning Methods For Cleaning Up Noisy Data

Ron Bekkerman

Sunday, 4.1.2009, 14:30

Room 337-8 Taub Bld.

Theory Seminar: When and How Can Data be Efficiently Released with Privacy?

Guy Rothblum (M.I.T.)

Sunday, 4.1.2009, 12:00

Taub 6

We consider private data analysis in the setting in which a trusted and trustworthy curator, having obtained a large data set containing private information, releases to the public a "sanitization'' of the data set that simultaneously protects the privacy of the individual contributors of data and offers utility to the data analyst. We focus on the case where the process is non-interactive; once the sanitization has been released the original data and the curator play ...

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How to Solve it: New Techniques in Algebraic Cryptanalysis

Adi Shamir (The Weizmann Institute of Science)

Thursday, 1.1.2009, 14:30

Room 337-8 Taub Bld.

In this talk I will introduce a new kind of attack (called Cube Attack) on cryptographic schemes which can be represented by an (unknown) low degree polynomial with tweakable public variables such as a plaintext or IV and fixed secret variables such as a key. Its complexity is exponential in the degree but only polynomial in the key size, and it was successfully applied to several concrete cryptographic schemes. The talk will be self contained, ...

[Full version]

[Full version]

How to Solve it: New Techniques in Algebraic Cryptanalysis

Adi Shamir

Thursday, 1.1.2009, 14:30

Room 337-8 Taub Bld.