סמינר המחלקה להנדסה ביו רפואית

08 במאי 2016, 14:00 
חדר 315 הבניין הרב תחומי  

Professor Ying Zhang

Division of embryonic biology

State Key Laboratory of Stem Cell and Reproductive Biology,

Institute of Zoology, Chinese Academy of Sciences,

Beijing, China

 

Molecular and biomechanical regulation of embryo distribution and location during pregnancy

 

 The distribution and location of intrauterine embryo site(s) show conserved patterns in most mammalian species (in humans the embryo tends to implant in the uterine fundus while in rodents, embryos evenly distribute along the uterine horns). These long-term evolved embryo location pattern bears great significance for disruption of these pattern have adverse effects on pregnancy outcome. In the past ten years, we used different mouse models to study the molecular regulation of embryo distribution and found adrenergic signaling, aquaporins, steroid hormones are actively involved in intrauterine embryo distribution. Now we are working on the biomechanical aspects of embryo distribution regulation.

מיד לאחר הרצאת האורח:

 עמית רוזנר -תלמיד המחלקה להנדסה ביו רפואית לתואר שני  ירצה בנושא:

 Termination of Atrial Spiral Wave Drivers by Induced Traction into Peripheral Non 1:1 Conducting Regions – A Numerical Study

Introduction: Atrial ablation has been recently utilized to treat atrial fibrillation (AF) by isolation or destruction of arrhythmia drivers. In chronic or persistent AF patients these drivers often consist of one or few rotors at unknown exact locations, and several ablation attempts are commonly conducted before arrhythmia activity is terminated. However, the irreversible damage done to the atrial tissue may lead to recurrence of AF within months or few years after the procedure. Here we propose an alternative strategy to terminate rotor activity by its attraction to a low-energy depolarizing probe and its traction into a peripheral non 1:1 conducting region.

Methods: The feasibility of the proposed method was numerically tested in 2D models of chronic AF human atrial tissue. Left-to-right gradients of either acetylcholine (ACh) or potassium conductance were employed to generate distinct regions of 1:1 and non 1:1 conduction, characterized by their dominant frequency (DF) ratios. Spiral waves were established in the 1:1 conducting region, and raster scanning pattern was employed using a stimulating probe to attract the spiral wave tip. The probe was then linearly moved towards the boundary between the two regions.

Results and conclusions: Successful attraction and anchoring of spiral waves to the probe was demonstrated for all scanning configurations when the probe was <8mm from the spiral wave tip. Maximal traction velocity without loss of anchoring increased in a non-linear, monotonic way with increasing values of ACh concentration. Success rate of spiral wave termination was over 90% for regional DF ratios of as low as 1:1.2 and 100% for ratios over 1:1.4. Given that normally much higher ratios are measured in physiological atrial tissues, we envision this technique to provide a feasible, safer alternative to ablation procedures performed in persistent AF patients.

העבודה נעשתה בהנחיית ד"ר שרון זלוצי'בר, המחלקה להנדסה ביו רפואית, אוניברסיטת תל אביב

ההרצאה תתקיים ביום ראשון 08.05.16, בשעה 14:00

 בבניין הרב תחומי , חדר 315 אוניברסיטת תל אביב

סמינר המחלקה להנדסה ביו רפואית

01 במאי 2016, 14:00 
חדר 315 הבניין הרב תחומי  

Assessment of breast density and bilateral asymmetry for risk stratification and early detection of breast cancer

Dr. Dror Lederman

Breast cancer is the second most common type of non-skin cancer and the fifth most common cause of cancer death. It has long been shown that early detection of breast cancer may increase the treatment options, survivability, and chance for full recovery. Therefore, methods for earlier detection of breast cancer and risk stratification have long been of great interest. Mammography has been widely used for this purpose, both for screening and diagnosis. However, mammography interpretation suffers from relatively low detection sensitivity and specificity, especially in younger women (i.e., less than 50 years old), due to the low prevalence of breast cancer and denser breast tissue. In order to cope with this problem, we have been developing a novel methodology for mammography interpretation, which assesses the level of mammographic asymmetry between bilateral breasts as a major risk and diagnostic factor. The bilateral mammographic asymmetry information is combined with unilateral mammographic tissue information, to yield a fused risk-probabilistic model. In this talk, I will introduce our ongoing research work in this field, and in particular the proposed framework and set of algorithms that we have been developing for this purpose. I will also present our work on tissue density estimation. Some experimental results will be presented alongside with a discussion on the challenges and trends in this field of research.

 

Dror Lederman received the B.Sc., M.Sc. and Ph.D. degrees in Electrical and Computers Engineering in 1998, 2003 and 2009, respectively, and the B.EMS. (Bachelor in Emergency Medicine) degree in 2005, all from Ben-Gurion University of the Negev, Beer Sheba, Israel. Between 2009 and 2011 he was a research fellow at the Imaging Research Division, Department of Radiology, University of Pittsburgh, Pittsburgh, PA, USA, where he was primarily involved in development of computer-aided diagnosis for breast cancer and lung computed tomography. Dr. Lederman is now a research scientist at Intel Corporation and a senior lecturer at the Holon Institute of Technology.

 

 

ההרצאה תתקיים ביום ראשון 01.05.16, בשעה 14:00

 בחדר 315, הבניין הרב תחומי, אוניברסיטת תל אביב

 

 

EE Seminar: MST in Log-Star Rounds of Congested Clique

~~ (The talk will be given in English)

Speaker:  Dr. Merav Parter
                         MIT

Sunday, May 1st, 2016
15:00 - 16:00
Room 011, Kitot Bldg., Faculty of Engineering

MST in Log-Star Rounds of Congested Clique

Abstract
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.

 

01 במאי 2016, 15:00 
חדר 011, בניין כיתות-חשמל  

השקת חברה, וזכיה בפרסים

13 אפריל 2016

א) ברכות לפרופ' דוד מנדלוביץ ולסטודנט שלו אריאל רז על השקת החברה "יוניספקטרל" (http://ramifeig.wix.com/unispec ) שהיא חברה ראשונה שיצאה מקרן מומנטום. כידוע לכם לפני כשנתיים הוקמה קרן מומנטום לתמיכה במחקרים בעלי פוטנציאל מסחרי. הקרן מממנת פרויקטים במרחב המעבדה של החוקר ובהיקפים משמעותיים של עד מיליון דולר. אפשר וכדאי להגיש בקשות בכל השנה דרך רמות. אם תרצו להתיעץ אפשר לפנות לדוד מנדלוביץ או לרמות.

 

ב) ברכות לסטודנט רועי רמז (סטודנט של עדי אריה מהנדסת חשמל)  ולסטודנט שגם אייל תאומי (סטודנט על יאיר שוקף מהנדסה מכנית) על זכייה במלגה היוקרתית מטעם פרס דן דוד בממד זמן העתיד, מדע הננו.

לצפיה בכל חדשות הפקולטה

 

סמינר מחלקתי - מרסלו בכר

12 במאי 2016, 14:00 
בניין וולפסון חדר 206  

רועי אנואר

ENTROPY BASED EXPLICIT MATRIX FACTORIZATION FOR RECOMMENDER SYSTEMSENTROPY BASED EXPLICIT MATRIX FACTORIZATION FOR RECOMMENDER SYSTEMS

 

12 באפריל 2016, 14:00 
בניין וולפסון חדר 206  

Abstract :

Matrix factorization is a popular method for modeling user and item behaviors in recommender systems. Matrix factorization is used to capture the item and user biases when building a recommendation model, thus representing the User-Item-Rating space in a compact form. One of the most known methods used for matrix factorization is SVD (Singular Value Decomposition). With SVD, the usage of matrix factorization results in a representation of the original user-item-rating matrix as a combination of latent (implicit) dimensions, which are perceived as the user interests and the item attributes. Understanding these dimensions and their translation to true user preferences is a difficult task. Our research focuses on non-latent (explicit) factorization of the user-item-rating matrix. We show that, given existing item attributes, we may build an explicit model describing the user preferences. Using this model we demonstrate how to predict ratings using explicit attributes from the data. To select the best attribute for our model, we utilize the realization based entropy approach and define two new measures: (1) the space entropy and (2) the consent entropy. Using a combination of these entropies, we may quantify the contribution of each non-latent attribute to our prediction model. Using the Movielens datasets, we compare our results to the known "SVD" model, and show how our explicit model yields similar results. 

17/4/16

You are invited to attend a lecture

By

 

Moran Assif

M.Sc. student under supervision of Prof. Yossi Rosenwaks

School of Electrical Engineering, Dept. of Physical Electronics

Tel Aviv University

 

Analysis and Applications of Multiple State

Electrostatically Formed Nanowire Transistors

 

Electrostatically formed nanowire (EFN)-based transistors have recently been suggested as a single device with multiplexer functionality. In these transistors multiple gates and multiple drains transistors, the conduction path between source to one of the drains is determined by the bias applied to the two junction-side gates. If a specific bias is applied to the side gates, the conduction band electrons between them are confined to a well-defined area forming a narrow channel—the EFN. By applying a nonsymmetric bias on the side gates, the lateral position of the EFN can be controlled.

We present a simulation analysis of the different states of the MSET device, applications, the transient time between them and the power exerted during each transition. The dependence of transition time between states and leakage currents in cutoff state on different geometry parameters is also presented.

A discussion on the usage of the MSET device in digital applications will be presented along with an analog application of an RF switch.

 

 

 

 

Sunday, April 17, 2016, at 14:00

Room 200, Wolfson Building (deans office)

17 באפריל 2016, 14:00 
Room #200 Wolfson build.  
17/4/16

 

13.4.16

You are invited to attend a lecture

By

 

Alex Henning

 

 

Ph.D. student of Professor Yossi Rosenwaks

Electrical Engineering, Physical Electronics Department

Tel Aviv University

 

 

Electrostatically-formed Nanowire based Gas Sensor

 

To date, there is no gas sensing technology that can be directly incorporated into mobile electronic devices. A miniature sensing platform is required that is sufficiently stable as well as highly sensitive and selective to gaseous analytes, and compatible with standard semiconductor technology. A sensing technology based on a planar multiple gate field-effect transistor, the electrostatically-formed nanowire (EFN) based device, was recently introduced by our group for protein detection in liquid. This EFN device is compatible with CMOS technology.

In this talk, we demonstrate the EFN device as a sensor for volatile organic compounds (VOCs) of concentrations down to several parts per million. We show that analyte detection can be controlled with the fringing electric field strength at the sensor surface by adjusting the voltages applied to the surrounding gates. In this way, the sensor response can be tuned and selectivity enhanced. Furthermore, we show by atomic force microscopy based techniques and I-V characteristics that The EFN shape and position can be controlled with the bias applied on the two junction gates and the back gate.

 

 

Wednesday, 13 April 2016, at 16:00

Room 206, Wolfson Mechanical Engineering Building

13 באפריל 2016, 16:00 
011 Kitot  
13.4.16

 

EE Seminar: Learning to see by listening

~~ (The talk will be given in English)

Speaker:   Prof. William T. Freeman
                        Massachusetts Institute of Technology and Google

Monday, May 23rd, 2016
15:00 - 16:00
Room 011, Kitot Bldg., Faculty of Engineering

Learning to see by listening

Abstract
Children may learn about the world by pushing, banging, and manipulating things, watching and listening as materials make their distinctive sounds-- dirt makes a thud; ceramic makes a clink. These sounds reveal physical properties of the objects, as well as the force and motion of the physical interaction. We've explored a toy version of such learning-through-interaction by recording audio and video while we hit many things with a drumstick.
We developed an algorithm the predict sounds from silent videos of the drumstick interactions. The algorithm uses a recurrent neural network to predict sound features from videos and then produces a waveform from these features with an example-based synthesis procedure. We demonstrate that the sounds generated by our model are realistic enough to fool participants in a "real or fake" psychophysical experiment, and that the task of predicting sounds allows our system to learn to visually distinguish different materials.
Joint work with: Andrew Owens, Phillip Isola, Josh McDermott, Antonio Torralba, Edward H. Adelson http://arxiv.org/abs/1512.08512 to appear in CVPR 2016

Bio: 
William T. Freeman is the Thomas and Gerd Perkins Professor of Electrical Engineering and Computer Science at MIT, and a member of the Computer Science and Artificial Intelligence Laboratory (CSAIL) there. He was the Associate Department Head from 2011 - 2014. His current research interests include machine learning applied to computer vision, Bayesian models of visual perception, and computational photography. He received outstanding paper awards at computer vision or machine learning conferences in 1997, 2006, 2009 and 2012, and test-of-time awards for papers from 1990 and 1995. Previous research topics include steerable filters and pyramids, orientation histograms, the generic viewpoint assumption, color constancy, computer vision for computer games, and belief propagation in networks with loops. He is active in the program or organizing committees of computer vision, graphics, and machine learning conferences. He was the program co-chair for ICCV 2005, and for CVPR 2013.

 

23 במאי 2016, 15:00 
חדר 011, בניין כיתות-חשמל  

EE Seminar: Shape Matching and Mapping using Semidefinite Programming

~~(The talk will be given in English)

Speaker:   Shahar Kovalsky
                      Department of Computer Science and Applied Mathematics, Weizmann Institute

Monday, May 9th, 2016
15:00 - 16:00
Room 011, Kitot Bldg., Faculty of Engineering

Shape Matching and Mapping using Semidefinite Programming

Abstract
Geometric problems - such as finding corresponding points over a collection of shapes, or computing shape deformation under geometric constraints - pose various computational challenges. I will show that despite the very different nature of these two highly non-convex problems, Semidefinite Programming (SDP) can be leveraged to provide a tight convex approximation in both cases. A different approach is used for each problem, demonstrating the versatility of SDP:
(i) For establishing point correspondences between shapes, we devise an SDP relaxation. I will show it is a hybrid of the popular spectral and doubly-stochastic relaxations, and is in fact tighter than both.
(ii) For the computation of piecewise-linear mappings, we introduce a family of maximal SDP restrictions. Solving a sequence of such SDPs enables the optimization of functionals and constraints expressed in terms of singular values, which naturally model various geometry processing problems.

Bio: 
Shahar Kovalsky is a PhD student in the department of Computer Science and Applied Math at the Weizmann Institute of Science, Israel. His main research interests are in numerical optimization, computer graphics and vision, and in particular, applications of convex optimization to geometry processing. Shahar holds a B.Sc. in Mathematics and B.Sc. and M.Sc. in Electrical Engineering from Ben-Gurion University.

 

09 במאי 2016, 15:00 
חדר 011, בניין כיתות-חשמל  

עמודים

אוניברסיטת תל אביב עושה כל מאמץ לכבד זכויות יוצרים. אם בבעלותך זכויות יוצרים בתכנים שנמצאים פה ו/או השימוש שנעשה בתכנים אלה לדעתך מפר זכויות
שנעשה בתכנים אלה לדעתך מפר זכויות נא לפנות בהקדם לכתובת שכאן >>