# Colloquia and Seminars

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Computer Science events calendar in HTTP ICS format for of Google calendars, and for Outlook.

## Upcoming Colloquia & Seminars

• ### Coding Theory: Vector Network Coding Based on Subspace Codes Outperforms Scalar Linear Network Coding

Speaker:
Antonia Wachter-Zeh (CS, Technion)
Date:
Sunday, 1.5.2016, 14:30
Place:
Taub 601

This talk considers vector network coding based on rank-metric codes and subspace codes. Our main result is that vector network coding can significantly reduce the required field size compared to scalar linear network coding in the same multicast network.

The achieved gap between the field size of scalar and vector network coding is in the order of $q^{(\ell-1)t^2/\ell}-q^t$, for any $q \geq 2$, where $t$ denotes the dimension of the vector solution, and the number of messages is $2 \ell$, ${\ell \geq 2}$. Previously, only a gap of constant size had been shown. This implies also the same gap between the field size in linear and non-linear scalar network coding for multicast networks. Similar results are given for any number of odd messages greater than two. The results are obtained by considering several multicast networks which are variations of the well-known combination network.

Joint work with Tuvi Etzion.

• ### CSpecial Talk: MST in Log-Star Rounds of Congested Clique

Speaker:
Merav Parter (MIT)
Date:
Tuesday, 3.5.2016, 10:30
Place:
Taub 301

We present a randomized algorithm that computes a Minimum Spanning Tree (MST) in O(log^* n) rounds, with high probability, in the Congested Clique model of distributed computing. In this model, the input is a graph on n nodes, initially each node knows only its incident edges, and per round each two nodes can exchange O(log n) bits.

Our key technical novelty is an O(log^* n) Graph Connectivity algorithm, the heart of which is a (recursive) forest growth method, based on a combination of two ideas: a sparsity-sensitive sketching aimed at sparse graphs and a random edge sampling aimed at dense graphs.

Our result improves significantly over the $O(\log \log \log n)$ algorithm of Hegeman et al. [PODC 2015] and the $O(\log \log n)$ algorithm of Lotker et al. [SPAA 2003; SICOMP 2005].

This join work with Mohsen Ghaffari, MIT, CSAIL.

Bio:
Merav Parter is a Postdoctoral Fellow at MIT hosted by Prof. Nancy Lynch. She received a Ph.D. degree in Computer Science from the Weizmann Institute of Science under the guidance of Prof. David Peleg. Her thesis “The Topology of Wireless Communication and Applications” won the first place Feder prize award for best student work in communication technology. Parter is a Rothschild and Fulbright Fellow. In the past, she was a Google European Fellow in Distributed Computing, 2012. Her research interests focus on two aspects of reliable communication: fault tolerant graph structures and wireless communication. She’s particularly intrigued with bridging the gap between Electrical Engineering and Theoretical Computer Science.

• ### Pixel Club: Point Registration via Efficient Convex Relaxation

Speaker:
Haggai Maron & Nadav Dym (Weizmann Institute of Science)
Date:
Tuesday, 3.5.2016, 11:30
Place:
EE Meyer Building 1061

We will discuss two related works:
1) "Point Registration via Efficient Convex Relaxation" Point cloud registration is a fundamental task in computer graphics, and more specifically, in rigid and non-rigid shape matching. The rigid shape matching problem can be formulated as the problem of simultaneously aligning and labeling two point clouds in 3D so that they are as similar as possible. We name this problem the Procrustes matching (PM) problem. The non-rigid shape matching problem can be formulated as a higher dimensional PM problem using the functional maps method. High dimensional PM problems are difficult non-convex problems which currently can only be solved locally using iterative closest point (ICP) algorithms or similar methods. Good initialization is crucial for obtaining a good solution.

We introduce a novel and efficient convex SDP (semidefinite programming) relaxation for the PM problem. The algorithm is guaranteed to return a correct global solution of the problem when matching two isometric shapes which are either asymmetric or bilaterally symmetric. We show our algorithm gives state of the art results on popular shape matching datasets. We also show that our algorithm gives state of the art results for anatomical classification of shapes. Finally we demonstrate the power of our method in aligning shape collections.

2) "Exact Recovery with Symmetries for Procrustes Matching" In this talk we analyze the PM semi-definite relaxation. We demonstrate some natural theoretical properties of the relaxation. We use the moment interpretation of [Lasserre, 2000] to show that for problems without noise and with (generic) input shapes which are asymmetric or bilaterally symmetric, the relaxation returns a correct solution of PM. For symmetric shapes, PM has multiple solutions. The non-convex set of optimal solutions of PM is strictly contained in the convex set of optimal solutions of PM-SDP, so that solutions of PM-SDP may not be solutions of PM. We deal with this by showing the solution set of PM to be the extreme points of the solution set of PM-SDP, and suggesting a random algorithm which returns a solution of PM with probability one, and returns the solutions of PM with equal probability. To the best of our knowledge there are no previous works on exact recovery in the presence of multiple solutions.

Joint work with Itay Kezurer, Shahar Kovalsky and Yaron Lipman.

• ### Pixel Club: Patch-Ordering as a regularization for Inverse Problems in Image Processing

Speaker:
Grisha Vaksman (Technion)
Date:
Tuesday, 3.5.2016, 12:30
Place:
EE Meyer Building 1061

In recent years much work has been devoted to the development of image processing algorithms using local patches. The main idea in this line of work is to impose a statistical prior on the patches of the desired image. An algorithm following this path extracts all possible patches with overlaps from the image, and operates on each separately. The more advanced algorithms exploit also interrelations between different patches in the reconstruction process.

In this work we further study the interrelations between patches, and harness it to propose a simple yet effective regularization for image restoration problems. Our approach builds on the classic Maximum A'posteriori probability (MAP) estimator, while using a novel permutation-based regularization term, following the work of Ram et. al. (2014). The permutation is obtained by a crude patch-ordering operation, and the prior employed within the MAP forces smoothness along the 1D pixel-path obtained. We demonstrate the success of the proposed scheme on a diverse set of problems: (i) severe Poisson image denoising, (ii) Gaussian image denoising, (iii) image deblurring, and (iv) single image super-resolution.

Note: the talk will be given in Hebrew.

• ### Welfare Maximization via Posted Prices

Speaker:
Michal Feldman - COLLOQUIUM LECTURE
Date:
Tuesday, 3.5.2016, 14:30
Place:
Room 337-8 Taub Bld.
http://www.cs.technion.ac.il/~colloq/20160503_14_30_Feldman.html
• ### ceClub: IoT-Enabled Community Care Provisioning for Sustainable Ageing-in-Place: A Singapore Example

Speaker:
Tan Hwee Pink (School of Information Systems, Singapore Management University)
Date:
Wednesday, 4.5.2016, 11:30
Place:
EE Meyer Building 861

In 2014, 12.4% of the population in Singapore were above 65 years of age and this is projected to increase to 19% by 2030. Among them, those living alone is likely to increase to 83,000 by 2030, up from 35,000 today. The ability to “age in place” - living where you have lived for years with reasonable quality of life, is especially important for the latter group. While Internet of Things (IoT)-enabled ambient intelligence environments that allow caregivers to remotely monitor a loved one’s activities 24/7 are emerging, most of the above systems are technology-centric, operate in silos and do not tie in with end-to-end care provisioning. Moreover, the elderly community exhibit huge variations in their living patterns and behaviour and a one-size-fits-all system will probably not work for all. In this presentation, I will talk about SHINESeniors, an SMU-initiated effort to tackle the above issues through the integration of ambient intelligence with care provisioning, and the personalization of such systems. This research project, supported by the Ministry of National Development and National Research Foundation under the Land and Liveability National Innovation Challenge (L2NIC) funding, is a collaborative effort with A*STAR, Eastern Health Alliance, a voluntary welfare organization, GoodLife!, Tata Consultancy Services, Ministry of Health, Housing and Development Board, and Urban Redevelopment Authority in Singapore.

Bio:
Dr. Hwee-Pink TAN currently leads a team of 10 technology and social science researchers to bring together Internet of Things technologies, and social-behavioural research to enable and sustain ageing-in-place, leading, in a broader sense, to intelligent and inclusive societies. Prior to joining SMU in March 2015, he spent 7 years at the Institute for Infocomm Research (I2R), A*STAR, where he was a Senior Scientist and concurrently the SERC Programme Manager for the A*STAR Sense and Sense-abilities Program. In this programme, he led a team of 30 full-time research scientists and engineers to design, pilot and evaluate architectures to support large scale and heterogeneous sensor systems to enable Smart City applications. In recognition of his contributions, he was awarded the I2R Role Model Award in 2012 and 2013, and the A*STAR Most Inspiring Mentor award, TALENT and Borderless Award in 2014. He graduated from the Technion, Israel Institute of Technology, Israel in August 2004 with a Ph.D. In December 2004, he was awarded the A*STAR International Postdoctoral Fellowship. From December 2004 to June 2006, he was a post-doctoral research at EURANDOM, Eindhoven University of Technology, The Netherlands. He was a research fellow with The Telecommunications Research Centre (CTVR), Trinity College Dublin, Ireland between July 2006 and March 2008. He is a Senior Member of the IEEE, has published more than 100 papers, has served on executive roles for various conferences on wireless sensor networks, and is an Area Editor of the Elsevier Journal of Computer Networks. He was Deputy Chair for the ITSC IoT Committee between July 2014 and March 2015. Lastly, he also recently co-founded and chairs the technology and innovation committee of the Stroke Support Station, a registered charity with a focused mission to help Stroke Survivors re-learn and enjoy active living for a better quality of life.

• ### Theory Seminar: The Possibilities and Limitations of Private Prediction Markets

Speaker:
Rachel Cummings (California Institute of Technology)
Date:
Wednesday, 4.5.2016, 12:30
Place:
Taub 201

Joint work with David Pennock and Jennifer Wortman Vaughan.

• ### Algebraic RAM

Speaker:
Evgenya Pergament, M.Sc. Thesis Seminar
Date:
Wednesday, 4.5.2016, 13:30
Place:
Taub 601
Prof. Eli Ben-Sasson

Due to the lack of computational power, many users don't perform the computation locally, rather outsource the computation to a remote server. This raises the problem of computational integrity. Using Probabilistically Checkable Proofs (PCP) the remote server can prove to the user (with high probability) that the computation was executed correctly. Although every language in NEXP is known to have a PCP system, previous works have not specified the process of converting instances of the bounded halting problem for random access machines (RAM) to instances of a "PCP friendly" NEXP complete language. This problem is highly relevant to the task of creating PCPs for practical problems. We define and describe a general method for representing bounded time RAM programs as instances of a NEXP complete "algebraic constraint satisfaction problem", that are PCP friendly.

• ### Interpreting the Ratio Criterion for Matching SIFT Descriptors

Speaker:
Avraham Kaplan, M.Sc. Thesis Seminar
Date:
Wednesday, 4.5.2016, 16:30
Place:
Taub 601
Prof. M. Lindenbaum and Dr. T. Avaraham

Matching keypoints by minimizing the Euclidean distance between their SIFT descriptors is an effective and extremely popular technique. Using the ratio between distances, as suggested by Lowe, is even more effective and leads to excellent matching accuracy. Probabilistic approaches that model the distribution of the distances were found effective as well. This work focuses, for the first time, on analyzing Lowe's ratio criterion using a probabilistic approach. We provide two alternative interpretations of this criterion, which show that it is not only an effective heuristic but can also be formally justified. The first interpretation shows that Lowe's ratio corresponds to a conditional probability that the match is incorrect. The second shows that the ratio corresponds to the Markov bound on this probability. The interpretations make it possible to slightly increase the effectiveness of the ratio criterion, and to obtain matching performance that exceeds all previous (non-learning based) results.

• ### Pixel Club: Visual Perception through Hyper Graphs

Speaker:
Nikos Paragios (CentraleSupelec, Inria, University of Paris-Saclay)
Date:
Thursday, 5.5.2016, 11:30
Place:
Room 337-8 Taub Bld.

Computational vision, visual computing and biomedical image analysis have made tremendous progress of the past decade. This is mostly due the development of efficient learning and inference algorithms which allow better and richer modeling of visual perception tasks. Hyper-Graph representations are among the most prominent tools to address such perception through the casting of perception as a graph optimization problem. In this talk, we briefly introduce the interest of such representations, discuss their strength and limitations, provide appropriate strategies for their inference learning and present their application to address a variety of problems of visual computing.

Bio:
Nikos Paragios is professor of Applied Mathematics and Computer Science and director of the Center for Visual Computing of CentraleSupelec. Prior to that he was professor/research scientist (2004-2005, 2011-2013)at the Ecole Nationale de Ponts et Chaussees, affiliated with Siemens Corporate Research (Princeton, NJ, 1999-2004) as a project manager, senior research scientist and research scientist. In 2002 he was an adjunct professor at Rutgers University and in 2004 at New York University. N. Paragios was a visiting professor at Yale (2007) and at University of Houston (2009). Professor Paragios is an IEEE Fellow, has co-edited four books, published more than two hundred papers in the most prestigious journals and conferences of medical imaging and computer vision (DBLP server), and holds twenty one US patents. His work has approx 15,750 citations according to Google Scholar and his H-number (03/2016) is 60. He is the Editor in Chief of the Computer Vision and Image Understanding Journal and serves as a member of the editorial board for the Medical Image Analysis Journal (MedIA) and the SIAM Journal in Imaging Sciences (SIIMS). He as served as an associate/area editor/member of the editorial board for the IEEE Transactions on Pattern Analysis and Machine Intelligence (PAMI), the Computer Vision and Image Understanding Journal (CVIU), the International Journal of Computer Vision (IJCV) and the Journal of Mathematical Imaging and Vision (JMIV) while he was one of the program chairs of the 11th European Conference in Computer Vision (ECCV'10, Heraklion, Crete) and serves regularly at the conference boards of the most prestigious events of his fields (ICCV, CVPR, ECCV, MICCAI). Professor Paragios is member of the scientific council of SAFRAN conglomerate.

• ### CGGC Seminar: Regularized Harmonic Map Flow: a Tool for Improvement of Maps between Shapes

Speaker:
Danielle Ezuz (CS, Technion)
Date:
Sunday, 8.5.2016, 13:30
Place:
Room 337-8 Taub Bld.

The problem of computing shape correspondence is a fundamental task in Computer Graphics. While recent methods produce semantically meaningful maps globally, the maps are distorted locally.

The harmonic map heat flow is a tool for local minimization of the Dirichlet energy, that measures the smoothness of a map. While the discrete harmonic map flow has been used, for example, to conformally map shapes to a sphere, when the target shape is arbitrary applying this flow can have a negative effect globally.

We suggest a regularization of this flow, using geodesic directions and additional extrinsic normals information, that produces smoother maps that remain globally meaningful.

This tool can be extremely beneficial for texture transfer and reducing distortion of ground-truth correspondence.

• ### The Finals - 2015-16 Amdocs Best Project Contest

Date:
Sunday, 8.5.2016, 14:30
Place:
CS Taub Auditorium 2

You are invited to the final stage of the 2015-16 Amdocs Best Project Contest. The competing teams will present and talk about their projects.

The event will take place on Sunday,May 8, 2015, 14:30-16:30, in Auditorium 2, CS Taub Building.

You are all invited to cheer, support and be exposed to outstanding projects.

• ### Unsupervised Ensemble Learning

Speaker:
Date:
Tuesday, 10.5.2016, 14:30
Place:
Room 337-8 Taub Bld.
• ### Secure Computation in Hostile Environments

Speaker:
Daniel Genkin, Ph.D. Thesis Seminar
Date:
Wednesday, 11.5.2016, 12:00
Place:
Taub 601
Prof. Yuval Ishai and Dr. Eran Tromer

The ubiquitous nature of computer systems means that they often operate in hostile environments where they are subjected to various attacks by adversarial parties. The purpose of such attacks varies, ranging from simply corrupting the system's behaviour to a complete extraction of otherwise-unavailable secret information. My research explores theoretical and practical aspects of designing computer systems which can securely operate in hostile environments. In the talk I will describe two aspects of my research: 1. The vulnerability of computer systems to side-channel attacks designed to extract externally-unavailable secret information. 2. The design of secure multiparty computation protocols which guarantee the security of distributed computations even in the presence on an active adversary. Our protocols are based novel techniques for designing circuits resilient to specific types of attacks, which might be of independent interest. The talk will include live and edible demonstrations.

• ### The 6th Annual International TCE Conference on 3D Visual Computing: Graphics, Geometry and Everything in Between.

Date:
Tuesday, 24.5.2016, 09:00
Place:
Churchill Auditorium, Technion, Haifa

The 6th annual international TCE conference (Tuesday-Wednesday, May 24-25, 2016) will focus on recent trends in 3D Visual Computing: Graphics, Geometry and everything in between.

Conference Chairs: Mirela Ben-Chen (CS Technion), Yoav Schechner (EE Technion)

With the advent of widespread consumer devices generating 3D data, as well as the recent advances in 3D printing, computing with 3D data has become a prominent ingredient in many fields in science and engineering. Having sound theoretical foundations for computational algorithms handling 3D data is therefore of great importance for devising robust, stable and efficient numerical methods. Topics will include Computer Graphics, Geometry Processing and Imaging, recently emerging algorithms for related 3D Visual Computing issues, and application challenges from both the industry and the academic arenas. A complete program and list of speakers will be available on our website. Confirmed speakers include:

· Marc Alex, TU Berlin, Germany
· Thomas Funkhouser, Princeton University
· Eitan Grinspun, Columbia University
· Michael Kazhdan, Johns Hopkins Universiy
· Niloy Mitra, UC London, UK
· Marc Pollefeys, ETH Zurich, Switzerland
· Helmut Pottmann, TU Wien, Austria
· Srinivasa Narasimhan, Carnegie Mellon University

Registration and more details about the conference and information on TCE.

• ### CS RESEARCH DAY 2016

Date:
Tuesday, 31.5.2016, 15:30
Place:
CS Taub

The Sixth CS Research Day for graduate studies will be held on Tuesday, May 31, 2016, between 15:30-17:30, at the lobby of the CS Taub Building.

Research Day events are opportunity for our graduate students to expose their researches using posters and presentations to CS faculty and all degrees students, Technion distinguished representatives and to high-ranking delegates from the hi-tech leading industry companies in Israel and abroad.

The participating researches will be on various topics: Theory of Computer Science, Systems, Artificial Intelligence and World Wide Web, Intelligent Systems and Scientific Computation, Bioinformatics.

Participating is free but requires preregistration.

More details and registration

• ### Intel@Technion Lectures: Game Changing Design

Speaker:
Shlomit Weiss (Intel)
Date:
Wednesday, 1.6.2016, 11:30
Place:
Room 337-8 Taub Bld.

produce design developed in through the years in many fronts and requirements. Today SOC products require aggressive targets in all fronts: frequency, performance, low cost, low power…… To address those new and growing requirement there needs to be a basic change in the design concept and solutions. Working in parallel convergence, parallel fronts and analyze tradeoffs together is the approach used to being the best SOC products to the market. This talk is describing the challenge and principals in applying the new approach.

Short bio:
Shlomit Weiss, VP Data Center Group – General Manager Silicon Development Networking Group, Intel. In her previous role Shlomit was GM of Client Products Development responsible design of all Client SOC products. In her role managed a cross site organization of about 650 people. Between the products designed and developed in the organization 6th generation “Core names Best processor Ever”. She is based in Intel Israel, has been at Intel since 1989, with a third of her time in different positions in the US. In her career at Intel Weiss has worked in various projects starting in validation, design, cluster manager, and architecture. Previously Weiss managed the architecture of the Intel® Core™ 2 Duo processor definition receiving an Intel Achievement Award, one of most prestigious Intel awards, for the architecture of that CPU. Weiss earned her master's degree cum laude in computer engineering from Technion in Haifa, Israel. In her limited free time, Shlomit enjoys traveling, folk dancing and spending time with her family.