Technion – Israel Institute of Technology

About: Technion – Israel Institute of Technology is a education organization based out in Haifa, Israel. It is known for research contribution in the topics: Population & Upper and lower bounds. The organization has 31714 authors who have published 79377 publications receiving 2603976 citations. The organization is also known as: Technion Israel Institute of Technology & Ṭekhniyon, Makhon ṭekhnologi le-Yiśraʼel.

Selected topics in robust convex optimization

Abstract: Robust Optimization is a rapidly developing methodology for handling optimization problems affected by non-stochastic “uncertain-but- bounded” data perturbations. In this paper, we overview several selected topics in this popular area, specifically, (1) recent extensions of the basic concept of robust counterpart of an optimization problem with uncertain data, (2) tractability of robust counterparts, (3) links between RO and traditional chance constrained settings of problems with stochastic data, and (4) a novel generic application of the RO methodology in Robust Linear Control.

Public-key cryptography and password protocols

Abstract: We study protocols for strong authentication and key exchange in asymmetric scenarios where the authentication server possesses ~a pair of private and public keys while the client has only a weak human-memorizable password as its authentication key. We present and analyze several simple password authentication protocols in this scenario, and show that the security of these protocols can be formally proven based on standard cryptographic assumptions. Remarkably, our analysis shows optimal resistance to off-line password guessing attacks under the choice of suitable public key encryption functions. In addition to user authentication, we describe ways to enhance these protocols to provide two-way authentication, authenticated key exchange, defense against server's compromise, and user anonymity. We complement these results with a proof that strongly indicates that public key techniques are unavoidable for password protocols that resist off-line guessing attacks.As a further contribution, we introduce the notion of public passwords that enables the use of the above protocols in situations where the client's machine does not have the means to validate the server's public key. Public passwords serve as "hand-held certificates" that the user can carry without the need for specal computing devices.

Formation of helical beams by use of Pancharatnam-Berry phase optical elements.

Abstract: Spiral phase elements with topological charges based on space-variant Pancharatnam-Berry phase optical elements are presented Such elements can be achieved by use of continuous computer-generated space-variant subwavelength dielectric gratings We present a theoretical analysis and experimentally demonstrate spiral geometrical phases for infrared radiation at a wavelength of 106microm

Grid cells require excitatory drive from the hippocampus

Abstract: Previous evidence has suggested that hippocampal place fields in rodents arise from the summation of input from entorhinal grid cells. Here the authors show that perturbing excitatory backprojections from the hippocampus to the entorhinal cortex causes a gradual firing rate–dependent loss of grid pattern and an emergence of head-directional tuning in grid cells of the medial entorhinal cortex.