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zamani-foroushani--javad
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A Survey and Practical Comparison of Top Techniques on Fault tolerant CPU Design
, M.Sc. Thesis Sharif University of Technology ; Tabandeh, Mahmoud (Supervisor)
Abstract
Confronting with cosmic rays in electronic parts of space systems, especially in processors and their peripherals, has always been noteworthy topic. By decreasing the aspects of transistors and their voltages, fault occurrence problem in digital integrated circuits not only has been increased in space systems, but also infects on mission critical systems that work at ground level. Since there are many reports about the effect of high energy particles, like neutrons which are present in earth atmosphere, in sub-100 nm digital circuits.In this thesis we are discussing about architecture level techniques for hardening processors against soft errors of radiation.It has been done for each part of...
A Novel Cloud Manufacturing Service Composition Model for Realizing the Supply Chain Resilience Structure
, M.Sc. Thesis Sharif University of Technology ; Haji, Alireza (Supervisor) ; Fatahi Valilai, Omid (Co-Supervisor)
Abstract
globalization has altered the structure of supply chains and the way they operate. These changes have mainly intensified by novel manufacturing models, especially cloud manufacturing, a service-oriented model in which manufacture’s capabilities and distributed resources are shared through a centralized management and control of CMfg platforms. Thus, cloud manufacturing has enabled service providers to reduce their costs and enhance production speed by creating virtual production lines. However; while being beneficial, cloud manufacturing models can introduce new challenges. One of the goals of cloud manufacturing models is to provide the access to value added services so that available...
Design, Static and Dynamic Analysis of Crossbeam of a Gantry Milling Machine
, M.Sc. Thesis Sharif University of Technology ; Movahhedy, Mohammad Reza (Supervisor) ; Akbari, Javad (Supervisor)
Abstract
Gantry milling machines are one of the types of machine tools that have vast application in various industries. Considering requirements such as quality and roughness of work pieces which are becoming restricted day after day, it is necessary that various parts of this machine have sufficient functionality and precision so that it can fulfill the quality requirements; and production of these expensive machines be cost-effective. One of the most important parts of a gantry milling machines is its crossbeam that undergoes deflections when exposed to applied forces during work conditions and can have undesirable effect on work piece precision. Therefore, the goal of this research is to design...
Ambient Vibrations Effect on Sensitive Equipment Using Passive and Active Control Method
, M.Sc. Thesis Sharif University of Technology ; Bakhshi, Ali (Supervisor)
Abstract
Today, with improvements in industries such as the sensitive equipment’ industries and the optics industries which need great precision for their optimum performance, the need for a vibration-free environment is felt more than ever. The main objective in this thesis is the effective reduction of the effects of ambient vibrations on points on an optical concrete table using active control. In this research, other than separating the table with the passive method, the reduction of vibrations with active control and the LQR algorithm is investigated. In order to study the dynamic characteristics of the table and to observe the active control process better and more carefully, finite element...
Fabrication of Fibrin Sheets for Tissue Regeneration
, M.Sc. Thesis Sharif University of Technology ; Abdekhodaie, Mohammad Jafar (Supervisor)
Abstract
The cornea is a transparent, avascular, multilayer, connective tissue. When the erosion process of these cells occur, where natural and quick restoration is expected, corneal disorders begin. Regeneration of corneal tissue, using a biocompatible method is a great point of interest. Nowadays, scaffold based on amniotic membrane is used as a basement membrane in the regeneration of corneal tissue. Lots of researches focused on using auto graft scaffold to decrease the inflammation and infection of an allografts and synthetic scaffolds, while overcoming amniotic membrane’s weak mechanical properties. The aim of this survey is to construct an appropriate scaffold from patient’s own blood to...
Design of Traffic Generator for Security Evaluation of Industrial Network
,
M.Sc. Thesis
Sharif University of Technology
;
Jahangir, Amir Hossein
(Supervisor)
Abstract
Today's modern industrial control systems (ICS) and SCADA infrastructures, use industrial networks to communicate with the sensors and actuators installed in the field. In recent years the increase in use of standard protocols in this networks, and also the connection of industrial networks to the internet introduced new challenges in the area of industrial network security. The difference in the property, size, and requirements of this networks in comparison to legacy computer networks have made the legacy security solutions such as firewalls and IDS to not have enough efficiency. Some researches work on implementing new solution to meet the requirements of industrial networks in the area...
Reaction-diffusion equations with polynomial drifts driven by fractional brownian motions
, Article Stochastic Analysis and Applications ; Volume 28, Issue 6 , Oct , 2010 , Pages 1020-1039 ; 07362994 (ISSN) ; Sharif University of Technology
2010
Abstract
A reaction-diffusion equation on [0, 1]d with the heat conductivity k > 0, a polynomial drift term and an additive noise, fractional in time with H > 1/2, and colored in space, is considered. We have shown the existence, uniqueness and uniform boundedness of solution with respect to k Also we show that if k tends to infinity, then the corresponding solutions of the equation converge to a process satisfying a stochastic ordinary differential equation
Solvent-free synthesis of 3-benzylpyrano[3,2-c]pyran/chromene-2,5-diones via tandem reaction of 4-hydroxy-6-methyl-pyran-2-one and 4-hydroxycoumarin with Baylis-Hillman adduct acetates
, Article Scientia Iranica ; Vol. 21, issue. 3 , 2014 , p. 735-741 ; 1026-3098 ; 2345-3605 ; Koushki Foroushani, B ; Lotfi Kalahroodi, E ; Sharif University of Technology
2014
Abstract
4-hydroxycoumarin 2a and 4-hydroxy-6-methyl-pyran-2-one 2b were applied in a one-pot reaction with Baylis-Hillman adduct acetates 1 to form novel 3-benzylpyrano [3, 2-c] pyran-2, 5-diones 3 in high yields (70-85%). The synthesized framework is available in many biologically active moieties. The reaction was carried out under different conditions to achieve optimum conditions. The results indicated that Et3N, as a base under solvent-free conditions, was optimum. The reaction procedure and purification method are mild and straightforward
Nickel ferrite nanoparticles: An efficient and reusable nanocatalyst for a neat, one-pot and four-component synthesis of pyrroles
, Article RSC Advances ; Volume 5, Issue 23 , Feb , 2015 , Pages 18092-18096 ; 20462069 (ISSN) ; Koushki Foroushani, B ; Rezvani, H. R ; Sharif University of Technology
Royal Society of Chemistry
2015
Abstract
In this study nickel ferrite magnetic nanoparticles were applied as an efficient and reusable catalyst in the four-component synthesis of substituted pyrroles under neat conditions. The reaction was conducted using various amounts of catalyst at different temperatures and finally, application of 5 mol% of catalyst at 100 °C was determined as the optimum reaction condition. Results showed that nickel ferrite nanoparticles could catalyze the reaction at relatively short times (3-4 h) with high to excellent yields (70-96%). The catalyst could be recovered easily using an external magnetic field and reused nine times without any significant activity lost
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
New method of determination for pressure and shear frictions in the ring rolling process as analytical function
, Article Journal of Solid Mechanics ; Vol. 6, issue. 3 , 2014 , pp. 322-333 ; ISSN: 20083505 ; Sharif University of Technology
2014
Abstract
Ring rolling is one of the most significant methods for producing rings with highly precise dimensions and superior qualities such as high strength uniformity, all accomplished without wasting any materials. In this article, we have achieved analytical formulas for calculating the pressure and shear friction over the contact arcs between the rollers and ring in the ring rolling process for the material in general nonlinear hardening property. We have also asserted the best mathematical model to predict friction for rolling processes. The method we use is based on calculating the analytical stress distribution. In other words, by using of Saint-Venan principal the stress components are...
Fast maximum power point tracking for PV arrays under partial shaded conditions
, Article 2016 18th European Conference on Power Electronics and Applications, EPE 2016 ECCE Europe25 October 2016, Article number 7695463 ; 2016 ; 9789075815245 (ISBN) ; Parniani, M ; Zarei, S. F ; Mohammadian Foroushani, H ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2016
Abstract
P-V characteristic of photovoltaic (PV) arrays under partially shaded conditions (PSC) has multiple peaks, and conventional maximum power point tracking (MPPT) algorithms may fail to track the global maximum power point (GMPP) because of their insufficient intelligence in discriminating the local and global peaks. This paper proposes a novel fast MPPT method to achieve GMPP of PV array under all PSCs. The proposed method reduces the number of required samples and increases the speed of GMPP tracking based on comprehensive study of I-V and P-V characteristics of PV array. Performance of the proposed method has been evaluated in simulations of different PSCs. Also, its performance has been...
Sparse array design for millimeter-wave imaging
, Article 2016 IEEE Antennas and Propagation Society International Symposium, APSURSI 2016 - Proceedings, 26 June 2016 through 1 July 2016 ; 2016 , Pages 1039-1040 ; 9781509028863 (ISBN) ; Fakharzadeh, M ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2016
Abstract
In this paper, the design of an efficient sparse array, used to reconstruct the image from millimeter-wave signals, is presented. The proposed array takes advantage of the sparsity concept of the image in the spatial Fourier domain to reduce the number of array elements such that the beam pattern of the designed array meets the desired beamwidth and sidelobe level. Simulation and measured results confirm the effectiveness of the proposed design on high-quality reconstruction of the image, while 85% reduction in the number of elements is achieved as well as the reduction in scan time and system complexity
A feature fusion based localized multiple kernel learning system for real world image classification
, Article Eurasip Journal on Image and Video Processing ; Volume 2017, Issue 1 , 2017 ; 16875176 (ISSN) ; Jamzad, M ; Sharif University of Technology
2017
Abstract
Real-world image classification, which aims to determine the semantic class of un-labeled images, is a challenging task. In this paper, we focus on two challenges of image classification and propose a method to address both of them simultaneously. The first challenge is that representing images by heterogeneous features, such as color, shape and texture, helps to provide better classification accuracy. The second challenge comes from dissimilarities in the visual appearance of images from the same class (intra class variance) and similarities between images from different classes (inter class relationship). In addition to these two challenges, we should note that the feature space of...
1.5-D sparse array for millimeter-wave imaging based on compressive sensing techniques
, Article IEEE Transactions on Antennas and Propagation ; Volume 66, Issue 4 , April , 2018 , Pages 2008-2015 ; 0018926X (ISSN) ; Fakharzadeh, M ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2018
Abstract
The goal of this paper is to reduce the antenna count in a millimeter (mm)-wave imaging system by proposing both hardware and software solutions. The concept of image sparsity in the transform domain is utilized to present the compressive sensing (CS) formulation for both mono-static and multistatic imaging at mm-wave frequencies. To reduce the complexity of the imaging system and reconstruction process, we introduce 1.5-D array structure, which is a random sparse array with orthogonal element locations. It is shown that the peak signal-to-noise ratio (PSNR) of the reconstructed image obtained by a 1.5-D array with 65% sparsity is very close to the PSNR of a uniform 2-D array for mono-static...
An efficient strategy to overproduce glutamic acid in Corynebacterium glutamicum fermentation
, Article Scientia Iranica ; Volume 8, Issue 3 , 2001 , Pages 203-206 ; 10263098 (ISSN) ; Roostaazad, R ; Sharif University of Technology
Sharif University of Technology
2001
Abstract
In this paper, effect of penicillin addition in enhancing the secretion of glutamic acid by Corynebacterium glutamicum was studied. The proper time of adding penicillin to maximize glutamic acid production was found to drift at repeated trials. In contrast, maximum acid productivity was obtained when penicillin was injected at a proper biomass concentration of about 7.7 gram dry weight per lit (gdw/l). Moreover, rate of consumption of sugar and ammonia through the course of glutamic acid fermentation was monitored. In production phase, these two rates were correlated properly with a ratio of 3.2:1 which is comparable to the theoretical stoichiometric value of 5:1. Therefore, through feeding...
Credit Risk Analysis of a Bank's Loan Portfolio
, M.Sc. Thesis Sharif University of Technology ; Zamani, Shiva (Supervisor)
Abstract
Risk management is one of the most important topics in banking. Risk management in banking is divided to several categories including credit risk. Credit risk is also divided to individual credit risk and portfolio credit risk. In Iran many of banks have worked on individual credit risk models, but few of them have worked on portfolio models because these models have developed only in recent years. In our project we present three categories of credit risk models and then analyze the data of a private bank in Iran with CreditPortfolioView model. In CreditPortfolioView model, macroeconomic parameters are used to analyze the correlated behavior of individuals as a benchmark in different...