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Hardware architecture for supersingular isogeny diffie-hellman and key encapsulation using a fast montgomery multiplier
, Article IEEE Transactions on Circuits and Systems I: Regular Papers ; Volume 68, Issue 5 , 2021 , Pages 2042-2050 ; 15498328 (ISSN) ; Bayat Sarmadi, S ; Mosanaei Boorani, H ; Alivand, A ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2021
Abstract
Public key cryptography lies among the most important bases of security protocols. The classic instances of these cryptosystems are no longer secure when a large-scale quantum computer emerges. These cryptosystems must be replaced by post-quantum ones, such as isogeny-based cryptographic schemes. Supersingular isogeny Diffie-Hellman (SIDH) and key encapsulation (SIKE) are two of the most important such schemes. To improve the performance of these protocols, we have designed several modular multipliers. These multipliers have been implemented for all the prime fields used in SIKE round 3, on a Virtex-7 FPGA, showing a time and area-time product improvement of up to 60.1% and 64.5%,...
Evaluation of Effective Factors on The Mammographic Images Utilizing Monte Carlo Simulation
, M.Sc. Thesis Sharif University of Technology ; Sohrabpour, Mostafa (Supervisor)
Abstract
The Scattered radiation is the principal factor affecting the quality of the digital and screen-film mammography images. The contrast improvement factor and bucky factor which are also referred to as the benefit and risk of the anti-scattered grid cannot be properly assessed without a detailed knowledge of the scattered radiation. In this work the scatter to primary ratio has been calculated and an anti-scatter grid has been designed based on the reduction of the scattered radiation to reduce the patient dose to a minimum level and to improve the image quality simultaneously.The MCNPX 2.6.0 Monte Carlo code has been used to improve the geometry of the anti-scatter grid to both reduce the...
Design of linear anti-scatter grid geometry with optimum performance for screen-film and digital mammography systems
, Article Physics in Medicine and Biology ; Volume 60, Issue 15 , July , 2015 , Pages 5753-5765 ; 00319155 (ISSN) ; Sohrabpour, M ; Sharif University of Technology
Institute of Physics Publishing
2015
Abstract
A detailed 3D Monte Carlo simulation of the grid geometrical parameters in screen-film mammography (SFM) and digital mammography (DM) systems has been performed. A combination of IEC 60627:2013 international standard conditions and other more clinically relevant parameters were used for this simulation. Accuracy of our results has been benchmarked with previously published data and good agreement has been obtained. Calculations in a wide range of linear anti-scatter grid geometries have been carried out. The evaluated parameters for the SFM system were the Bucky factor (BF) and contrast improvement factor (CIF) and for the DM system it was signal differenceto- noise ratio improvement factor...
The effects of viscous dampers on the reliability of steel structures using a PIF index
, Article Proceedings of the Institution of Civil Engineers: Structures and Buildings ; Volume 172, Issue 4 , 2019 , Pages 289-300 ; 09650911 (ISSN) ; Bakhshi, A ; Sharif University of Technology
ICE Publishing
2019
Abstract
A new comparative performance measure based on a structure's seismic fragility curve is introduced. This factor, called the performance improvement factor (PIF), was used to compare the seismic performance and reliability of two structures. Using the PIF, the efficiency of viscous dampers on the behaviour of a weak mid-rise steel structure was investigated. A prototype five-span 12-storey steel frame was equipped with three patterns of viscous dampers and their seismic performance was studied. The distribution of dampers along the height of the structure was optimised in three hazard levels using a genetic algorithm and the structure was subjected to 12 ground motion records scaled to levels...