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mahmoudi--amin
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Introducing a Simulation-Based Model to Improve the Design and Layout of Workstations Inside Airport Terminals in Iran
, M.Sc. Thesis Sharif University of Technology ; Alvanchi, Amin (Supervisor)
Abstract
The airport terminal is difficult to plan and design due to the different components and the intricate complexity of its parts. At the airport terminal, we face a queue system which simulation is always a good way to analyze. In addition, computer simulation using modern softwares with the capability to model different types of systems, including the airport terminal, while being less realistic than analytical models, is less costly than operational Exercise.In this study, a supportive approach for better and specific management of Iranian airport terminal buildings with discrete-event simulation is proposed, considering the need for managing the airport terminals building in the country and...
, M.Sc. Thesis Sharif University of Technology ; Alvanchi, Amin (Supervisor)
Abstract
Limited water resources in Iran have made dams an important part of the country’s infrastructure. As a result of the large number of in-progress and expected dam projects in the country, consideration of sustainability factors during planning, construction and operation phases of dam projects can create significant economical, social and environmental impacts in the long term. To come up with an inclusive sustainable development, new sustainability assessment approaches seek for sustainable development at the entire project’s life-cycle; they are looking for sustainable development at all design, construction, operation, maintenance and even demolition phases. In this research we have...
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....
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...
Vehicle Routing Problem with Environmental Considerations
, M.Sc. Thesis Sharif University of Technology ; Eshghi, Kourosh (Supervisor)
Abstract
Transportation services enable economic growth of countries and account as a major part of Gross National Product (GNP) but on the other hand have negative environmental impacts including Greenhouse Gas (GHG) emissions, noise pollution and toxic effects on the ecosystem such as acid rain. The traditional objective of distribution management is usually minimizing economic costs. Given the existing environmental problems, ecological and social effects of transportation should be considered in addition to the conventional economic costs. In this study, a special type of Vehicle Routing Problem (VRP) with a heterogeneous vehicle fleet that in which environmental and traffic considerations taken...
Simultanous Optimization of Water and Energ in Steel Production Based on Modified Superstructure
, M.Sc. Thesis Sharif University of Technology ; Saboohi, Yadollah (Supervisor)
Abstract
In a steel production plan primary resources entered the process are converted to high value products and byproducts. To this end, resources need to pass several consecutive process that require utility streams. One could not achieve the optimum operation of an industrial process unless they maximize the product and minimize the utility and waste. Therefore, it is important to consider the process stream integrated. The aim of this work is to find the optimum consumption of water and energy in a steel production and to calculate the potential reduction in water and energy resource destruction. Present work could be define a mathematical programing problem in which water users and all streams...
Peak Power Efficient Scheduling in Mixed-criticality Embedded Systems
, M.Sc. Thesis Sharif University of Technology ; Ejlali, Alireza (Supervisor)
Abstract
Due to the continuing progress in CMOS technology and increased number of cores within a chip, multiple components with different levels of criticality have been integrated into a common hardware platform. These systems with these characteristics are known as Mixed-Criticality Systems (MCS). Also, due to the migration towards multi-core systems, power consumption and specifically instantaneous power consumption is the main concern. To avoid the use of cooling technology, we need to reduce the instantaneous power consumption of the system. However, most existing approaches in MCS have paid attention to reliability guaranteed and energy minimization. Therefore, we consider a dynamic scheduling...
On the biological performance of graphene oxide-modified chitosan/polyvinyl pyrrolidone nanocomposite membranes: In vitro and in vivo effects of graphene oxide
, Article Materials Science and Engineering C ; Volume 70 , 2017 , Pages 121-131 ; 09284931 (ISSN) ; Simchi, A ; Sharif University of Technology
Elsevier Ltd
2017
Abstract
Nanofibrous structures that mimic the native extracellular matrix and promote cell adhesion have attracted considerable interest for biomedical applications. In this study, GO-modified nanofibrous biopolymers (GO) were prepared by electrospinning blended solutions of chitosan (80 vol%), polyvinyl pyrrolidone (15 vol%), polyethylene oxide (5 vol%) containing GO nanosheets (0–2 wt%). It is shown that GO nanosheets significantly change the conductivity and viscosity of highly concentrated chitosan solutions, so that ultrafine and uniform fibers with an average diameter of 60 nm are spinnable. The GO-reinforced nanofibers with controlled pore structure exhibit enhanced elastic modulus and...