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mahmoudi--javad
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Cryptanalysis of Two Authenticated Encryption Schemes Pr∅st and NORX Introduced in CAESAR
, M.Sc. Thesis Sharif University of Technology ; Aref, Mohammad Reza (Supervisor) ; Mohajeri, Javad (Co-Advisor)
Abstract
The goal of authenticated encryption is to ensure confidentiality, integrity and authenti-cation of the messages simultaneously. The anouncement of CAESAR comptetition has attracted esearchers’ attention to this branch of symmetric cryptography, since 2014. 57 schemes have been introduced as the first round candidates of this competition, from which 29 where selected as second round candidates. Cryptanalysis of these schemes needs a lot of collective effort. In this thesis after describing preliminaries of authen- ticated encryption, general structure of the schemes and their reported cryptanalysis is reviewed. Then, the details of Pr∅st family of authenticated encryption, which is one of...
A fuzzy random minimum cost network flow programming problem [electronic resource]
, Article Journal of Industrial and Systems Engineering (JISE)-Iranian Institute of Industrial Engineering ; Article 3, Volume 6, Issue 1, Spring 2012, Page 34-47 ; Eshghi, Kourosh ; Sharif University of Technology
Abstract
In this paper, a fuzzy random minimum cost flow problem is presented. In this problem, cost parameters and decision variables are fuzzy random variables and fuzzy numbers respectively. The object of the problem is to find optimal flows of a capacitated network. Then, two algorithms are developed to solve the problem based on Er-expected value of fuzzy random variables and chance-constrained programming. Furthermore, the results of two algorithms will be compared. An illustrative example is also provided to clarify the concept
Special classes of mathematical programming models with fuzzy random variables [electronic resource]
, Article Journal of Intelligent and Fuzzy Systems, Published In: IOS Press ; Volume 19, Number 2, 2008 ; Nematian, Javad ; Sharif University of Technology
Abstract
In this paper, we will discuss two special classes of mathematical programming models with fuzzy random variables. In the first model, a linear programming problem with fuzzy decision variables and fuzzy random coefficients is introduced. Then an algorithm is developed to solve the model based on fuzzy optimization method and fuzzy ranking method. In the second model, a fuzzy random quadratic spanning tree problem is presented. Then the proposed problem is formulated and solved by using the scalar expected value of fuzzy random variables. Furthermore, illustrative numerical examples are also given to clarify the methods discussed in this paper
A special class of fuzzy integer programming model with all different constraints [electronic resource]
, Article Scientia Iranica ; Vol. 16, No. 1, pp. 1-10, 2009 ; Nematian, Javad ; Sharif University Of Technology
Abstract
In this paper, a fuzzy approach is applied to special classes of integer programming problems with all diierent constraints. In the rst model, a fuzzy integer programming model is developed to represent the all-diierent constraints in mathematical programming. In order to solve the proposed model, a new branching scheme for the Branch and Bound algorithm is also presented. In the second model, a special class of large-scale multi-objective fuzzy integer programming problems with all-diierent constraints is introduced. A solution method for the proposed model is also developed by using the decomposition technique, weighting method and Branch and Bound algorithm. An illustrative numerical...
Fuzzy random minimum cost network problem [electronic resource]
, Article Journal of Industrial and Systems Engineering ; Vol. 6, No. 1, pp 34-47, 2012 ; Eshghi, Kourosh ; Sharif University of Technology
Abstract
In this paper, a fuzzy random minimum cost flow problem is presented. In this problem, cost parameters and decision variables are fuzzy random variables and fuzzy numbers respectively. The object of the problem is to find optimal flows of a capacitated network. Then, two algorithms are developed to solve the problem based on Er-expected value of fuzzy random variables and chance-constrained programming. Furthermore, the results of two algorithms will be compared. An illustrative example is also provided to clarify the concept
Hyperbolic involutions and quadratic extensions
, Article Communications in Algebra ; Volume 39, Issue 1 , Jan , 2011 , Pages 125-132 ; 00927872 (ISSN) ; Sharif University of Technology
2011
Abstract
This is a variation on a theme of Bayer-Fluckiger, Shapiro, and Tignol related to hyperbolic involutions. More precisely, criteria for the hyperbolicity of involutions of quadratic extensions of simple algebras and involutions of the form σ ⊗ τ and σ ⊗ ρ, where σ is an involution of a central simple algebra A, τ is the nontrivial automorphism of a quadratic extension of the center of A, and ρ is an involution of a quaternion algebra are obtained
On hyperbolic clifford algebras with involution
, Article Algebra Colloquium ; Volume 20, Issue 2 , 2013 , Pages 251-260 ; 10053867 (ISSN) ; Sharif University of Technology
2013
Abstract
The aim of this article is to provide a characterization of quadratic forms of low dimension such that the canonical involutions of their Clifford algebras are hyperbolic
Orthogonal symmetries and Clifford algebras
, Article Proceedings of the Indian Academy of Sciences: Mathematical Sciences ; Volume 120, Issue 5 , November , 2010 , Pages 535-561 ; 02534142 (ISSN) ; Sharif University of Technology
2010
Abstract
Involutions of the Clifford algebra of a quadratic space induced by orthogonal symmetries are investigated
A quick proof of the 1, 2, 4, 8 theorem
, Article Expositiones Mathematicae ; Volume 33, Issue 3 , 2015 , Pages 375-377 ; 07230869 (ISSN) ; Sharif University of Technology
Elsevier GmbH
2015
Products of rotations by a given angle in the orthogonal group
, Article Bulletin of the Australian Mathematical Society ; 2017 , Pages 1-5 ; 00049727 (ISSN) ; Sharif University of Technology
2017
Abstract
For every rotation (Formula presented.) of the Euclidean space (Formula presented.) ((Formula presented.)), we find an upper bound for the number (Formula presented.) such that (Formula presented.) is a product of (Formula presented.) rotations by an angle (Formula presented.) ((Formula presented.)). We also find an upper bound for the number (Formula presented.) such that (Formula presented.) can be written as a product of (Formula presented.) full rotations by an angle (Formula presented.). © 2017 Australian Mathematical Publishing Association Inc
products of rotations by a given angle in the orthogonal group
, Article Bulletin of the Australian Mathematical Society ; Volume 97, Issue 2 , 2018 , Pages 308-312 ; 00049727 (ISSN) ; Sharif University of technology
Cambridge University Press
2018
Abstract
For every rotation of the Euclidean space ℝ(n≥3), we find an upper bound for the number such that is a product of rotations by an angle α( 0<≤π). We also find an upper bound for the number such that ρ can be written as a product of full rotations by an angle α. © 2017 Australian Mathematical Publishing Association Inc
A Geometric Interpretation of the Simplicity of SO(3)
, Article American Mathematical Monthly ; Volume 126, Issue 4 , 2019 , Pages 340-350 ; 00029890 (ISSN) ; Sharif University of Technology
Taylor and Francis Inc
2019
Abstract
This article aims to present a geometric interpretation of the simplicity of the rotation group of three-dimensional Euclidean space. Some historical remarks on the subject and an overview of a collection of different proofs of this result are also given
On normal subgroups of the unit group of a quaternion algebra over a pythagorean field
, Article Bulletin of the Iranian Mathematical Society ; Volume 46, Issue 1 , June , 2020 , Pages 253-262 ; Sharif University of Technology
Springer
2020
Abstract
We investigate the structure of normal subgroups of the unit group of a quaternion algebra over a pythagorean field. © 2019, Iranian Mathematical Society
Synthesis of a nanostructured MgH2–Ti alloy composite for hydrogen storage via combined vacuum arc remelting and mechanical alloying [electronic resource]
, Article Journal of Materials Letters ; 15 April 2011, Volume 65, Issue 7, Pages 1120–1122 ; Kaflou, A ; Simchi, A. (Abdolreza) ; Sharif University of Technology
Abstract
To improve the hydrogen kinetics of magnesium hydride, TiCr1.2Fe0.6 alloy was prepared by vacuum arc remelting (VAR) and the alloy was co-milled with MgH2 to process nanostructured MgH2–5 at.% TiCr1.2Fe0.6 powder. The hydrogen desorption properties of the composite powder were studied and compared with pure magnesium hydride. X-ray diffraction (XRD) analysis showed that the composite powder prepared by VAR/mechanical alloying (MA) procedure consisted of β-MgH2, γ-MgH2, bcc Ti–Cr–Fe alloy, and small amount of MgO. The average size of particles and their grain structure after 4 h MA were determined by a laser particle size analyzer and XRD method and found to be 194 nm and 11 nm, respectively....
Production of Uranium Dioxide Nano Powder With Hydrothermal Method in Supercritical Water Reactor
, M.Sc. Thesis Sharif University of Technology ; Outokesh, Mohammad (Supervisor) ; Ahmadi, Javad (Supervisor) ; Karimi Sabet, Javad (Co-Advisor)
Abstract
Hydrothermal supercritical method is one of the most suitable methods for metal oxide nano powder, ceramics and mineral catalyst synthesis. Metal oxides nanopowder in its pure or mixed form has wide potential application as chemical industrial catalyst, hot Superconductors, magnetic material, gas sensors and car catalyst convertors. One of the most important metal oxides aspects of application is uranium oxide as nuclear reactor fuel is used. In addition, UO2 is selective catalyst for converting methane to methanol process and Decomposition of organic Chlorine material. In Supercritical hydrothermal method done in high pressure reactor with critical to fluid, is new method for the...
The Effect of Protein Corona on Doxorubicin Release from the Magnetic Mesoporous Silica Nanoparticles and the Effect of Polyethylene Glycol Coating on drug Delivery System
, M.Sc. Thesis Sharif University of Technology ; Pourjavadi, Ali (Supervisor)
Abstract
The nanoparticles have been widely used in the field of physics, chemistry, electronics and mechanics because of their high surface area. One of their most important applications is in drug delivery systems as smart drug nanocarrier. Magnetic nanoparticles (including Fe2O3, Fe3O4) are the good candidates for this purpose. It is clear that, upon to entrance of nanoparticle into biological media (such as plasma), the surface of nanoparticles were covered by protein layers (protein corona). This layer is very stable and created new surface on the nanoparticles. The protein corona layer intracts with cellular receptors and determines the fate of nanoparticles. Protein corona covers the targeting...
Synthesis and Characterization of Cis-dioxomolybdenum(VI) Complex with an ONOtype Tridentate Schiff base Ligand and its Application as a Catalyst for Epoxidation of Olefinsin Water
, M.Sc. Thesis Sharif University of Technology ; Bagherzadeh, Mojtaba (Supervisor)
Abstract
New dioxomolybdenum(VI) complex has been synthesized by reacting N-hydroxyphenyl-[5-(triphenylphosphonium)methyl]salicylideneamine chloride (PPh3-H2sap) as a water soluble ligand and [MoO2(acac)2] in ethanolic solution. The water soluble ligand (PPh3-H2sap) was prepared by reaction of 2-aminophenol with (3-formyl-4-hydroxybenzyl)triphenylphosphonium chloride as a water solublesalicylaldehyde derivative. The resulting complex with the formula [MoO2(PPh3-H2sap)(EtOH)] which contains an ethanol molecule in sixth site of coordination, was characterized by elemental analyses, 1H NMR,31P NMR, IR and UV-Vis spectroscopic studies. This complex was tested as a catalyst for the homogeneous...
A genetic fuzzy expert system to optimize profit function
, Article Economic Computation and Economic Cybernetics Studies and Research ; Volume 8 , 2012 ; 0424267X (ISSN) ; Shavandi, H ; Sharif University of Technology
2012
Abstract
In this paper we develop a fuzzy system to obtain the demand based on input variables of price, warranty length and lead time of order delivery. We use linguistic terms to illustrate the situation of input and output variables and construct a fuzzy rule base. The fuzzy rule base is integrated with a genetic algorithm to construct a hybrid solution method. The best value of price, warranty length and lead time are obtained by maximizing the manufacturer profit. Finally a numerical example is presented to show the performance of proposed approach
Analyzing price, warranty length, and service capacity under a fuzzy environment: Genetic algorithm and fuzzy system
, Article Scientia Iranica ; Volume 20, Issue 3 , 2013 , Pages 975-982 ; 10263098 (ISSN) ; Shavandi, H ; Sharif University of Technology
2013
Abstract
In this article, we propose a bi-objective model for the pricing-queuing problem under a fuzzy environment. We consider two objectives: maximizing the profit function and minimizing the waiting time in queue. Imagine a firm which sells a product in a channel providing after sales services. The sales price and warranty length affect customer demand. We formulate the demand function as a fuzzy system considering the sales price and warranty length. The firm optimizes the sales price and warranty length, as well as waiting time, in the queue of after sales services, to maximize its revenues and minimize waiting time. To solve the derived model, we develop a hybrid solution method of a fuzzy...
Supply Chain Design of a Blood Banking System
, M.Sc. Thesis Sharif University of Technology ; Kourosh, Eshghi (Supervisor)
Abstract
This research is focused on inventory management of a blood banking system by assuming deterministic demand and supply with the objective function of minimizing the summation of shortage and wastage. In this research, two integer programming models are developed to solve the problem. In the first model, it is assumed that the blood groups are independent, but in the second one, the transactions between different blood groups are allowed, as it is in reality. Then, to be more efficient and practical, a dynamic heuristic algorithm is developed. In addition, we compared the solution of heuristic algorithm with the exact solutions derived from integer programming models. The data used in this...