School of Mechanical Engineering Seminar
Wednesday, March 11, 2015 at 15:00
Wolfson Building of Mechanical Engineering, Room 206

Interface Capturing Finite Element Strategies for Fluids

Alvaro L.G.A. Coutinho

High Performance Computing Center and Department of Civil Engineering
COPPE/Federal University of Rio de Janeiro
PO Box 68506, Rio de Janeiro, RJ 21945-970, Brazil
 

The hydrodynamics of fluid mixtures is receiving more and more attention in many science and engineering applications. Within the techniques for dealing with front displacements and moving boundaries between fluids with different density and viscosity, interface capturing are very successful. Among then we may find sharp interface methods such as Volume-of-Fluid and Level Sets. Phase fields are a class of models in which a diffusive transition region is taken into account instead of a steep interface. In this talk, we review general interface capturing methods and their finite element formulation on a pure Eulerian framework. Examples of interest in engineering and science are given. We explore here particular features of the classic Allen–Cahn (AC) phase field model. We introduce a modified AC model exploring its similarities with residual-based discontinuity- capturing schemes, making the phase field equation dependent on its own residual. In this case, we solve the coupling between the incompressible viscous fluid flow and the phase field advective–diffusive–reactive transport to simulate the main processes in interface tension and buoyancy-driven problems. Bubble interaction problems are studied to show the effectiveness of the new AC model. Results suggest that the proposed model is less parameter dependent and possess better conservation properties.

Propel Your PR with Smart Strategies  –  an evening with Alan Weinkrantz – legendary Startup PR / Communications Strategist --- plus a panel of local PR experts

This is a joint event of IsraelStartupNetwork and Shiluvim

February 16^th20:45- 18:00  at the Engineering School, TAU.

להרשמה לחץ כאן

Cognitive Robotics on the Factory Floor

Dr. Erez Karpas – MIT

Abstract:

Current manufacturing robots are typically preprogrammed to perform one fixed task efficiently. This requires a long, expensive, setup in order to integrate into an assembly line, and means making changes in the assembly process is difficult as well. Cognitive robots, which are endowed with the ability to reason, allow for faster setup through high level programming, and added flexibility in the assembly process. In this talk, I will present recent work on how cognitive robots can work with a human, responding to the human's actions intelligently, and on how they can deal with novel situations by coming up with a new course of action through replanning.

Bio:

Erez Karpas is a post-doctoral fellow at the Model-based Embedded and Robotic Systems group at MIT's Computer Science and Artificial Intelligence Lab. His research interests include autonomous systems, automated planning, heuristic search, and machine learning. He received his Ph.D. from the Technion - Israel Institute of Technology in 2012, and his M.Sc. and B.Sc. from Ben-Gurion University.

ההרצאה תתקיים ביום שלישי 10/2/15, בשעה 14:00 בחדר 206, בנין וולפסון הנדסה, הפקולטה להנדסה, אוניברסיטת תל-אביב

Physical Electronics Dept. SEMINAR

***** Seminar *****

You are invited to attend a lecture

by

Nir Atzmon

(Msc. student under the supervision of Prof. Eshel Ben-Jacob and Prof. Avraham Gover)

School of Electrical Engineering, Tel-Aviv University, Tel-Aviv 69978, Israel

Real-Time feedback stimulator for investigating neuroplasticity in cultured networks

In-vitro neuronal cultures offer exciting possibilities for studying neuronal information coding and processing. A network level approach is necessary to fully understand information processing in the brain, as every function in the human brain employs correlated activities of large populations of neurons. It was shown that synaptic plasticity plays a crucial role in the synchronized behavior of the network, and therefore investigating neuroplasticity in cultured networks may yield new insight as to the functions of neuronal circuits in the brain. While much is known on the cellular mechanism underlying synaptic plasticity, making the leap from the cellular level to the network level is far from trivial.  Previous studies aimed at uncovering the dynamics governing network plasticity have used open-loop assays to study the response of neuronal networks to external stimulation by combining electrical stimulation of cultured networks on multi-electrode arrays, in conjunction with extracellular recording.

In this work we developed a closed-loop assay for investigating neuroplasticity in cultured networks. The assay makes use of a real-time feedback stimulator (RTFS) that responds to network activity within a few milliseconds and is both generic and easily modified to suit different experimental setups. In order to demonstrate the potential of such a system in the study of network plasticity, we used the RTFS to generate electrical stimulation to the network based on real-time detection of spontaneous burst patterns and were able to show a decrease in inter-burst correlation, indicating attenuation of the synchronized activity of the network. These findings imply that similar closed loop assays can be used in the study of network-level plasticity, and a generic system, such as the one presented here, can open up a wide range of research possibilities, for example in the study of epilepsy. 

Sunday, February 8, 2015, at 15:00

Room 011, EE- KITOT building