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    Surveying Philosophical Arguments on "Origination of The Universe" based on the views of: W.L.Craig, Q.Smith and Allamah S.M.H Al-Tabatabaie

    , M.Sc. Thesis Sharif University of Technology Zare, Roozbeh (Author) ; Hosseini, Hassan (Supervisor)
    Abstract
    The problem of Origination of The Universe is one of the most important issues in the history of philosophy whether in western edition or in Islamic thought. The most problematic aspect of the Origination is Temporal Origination. From about 30 years ago as a result of the works of a famous American philosopher William Lane Craig, the debate between temporality and Eternity of the Universe became a fresh topic in western philosophy. In this research we want to survey the philosophical arguments for and against the temporality of the Universe based on the views of: W.L.Craig, Q.Smith and Allamah S.M.H Al-Tabatabaie.
     

    Design An Efficient Method for Solving Integer Programming by Lagrangian Relaxation

    , M.Sc. Thesis Sharif University of Technology Zare, Mahdi (Author) ; Eshghi, Kourosh (Supervisor)
    Abstract
    The subgradient method is one of the most favoriate methods to solve discrete optimization problems. The Easy Implementation and flexibility enbles us to solve a vast types of complicated combinatorial optimization problems. However, the algorithm can be improved by adjusting its parameters and steps.In present research, we present a heuristic structure to modify and improve the algorithm. Then, the proposed algorithm has tested on special classes of discrete optimization problems such as Generealized Assignment and Uncapacitated Warehouse location problems. The results show that the proposed algorithm can improve the efficiency of the classic form of subgradient method.The three main... 

    Preparation of Heterogeneous Catalysts by Immobilization of Molybdenum and Manganese-shiff Base Complexes into the Nanopores of Zeolite and SBA-15

    , Ph.D. Dissertation Sharif University of Technology Zare, Maryam (Author) ; Bagherzadeh, Mojtaba (Supervisor)
    Abstract
    This thesisconsiders new fundamental approaches to yield heterogeneous catalysts in to three sections. The first section described the immobilization of the molybdenum-Schiff base complexes in pores of SBA-15 in two different methodologies depending on the actual structure of the complexes., (i) stepwise formation of the complex by initial covalent anchoring of one of the components and consecutive solid phase synthesis consisting of the condensation of the other components of the salen complex (iii) one-step complex immobilization by covalent binding through the ligand.Based on the first methodology, we report the preparation of ordered mesoporous silica SBA-15 containing a molybdenum... 

    Influence of martensite volume fraction on impact properties of triple phase (TP) steels

    , Article Journal of Materials Engineering and Performance ; Volume 22, Issue 3 , 2013 , Pages 823-829 ; 10599495 (ISSN) Zare, A ; Ekrami, A ; Sharif University of Technology
    2013
    Abstract
    Ferrite-bainite-martensite triple phase (TP) microstructures with different volume fractions of martensite were obtained by changing heat treatment time during austempering at 300 C. Room temperature impact properties of TP steels with different martensite volume fractions (VM) were determined by means of Charpy impact testing. The effects of test temperature on impact properties were also investigated for two selected microstructures containing 0 (the DP steel) and 8.5 vol.% martensite. Test results showed reduction in toughness with increasing VM in TP steels. Fracture toughness values for the DP and TP steels with 8.5 vol.% martensite were obtained from correlation between fracture... 

    Effect of martensite volume fraction on work hardening behavior of triple phase (TP) steels

    , Article Materials Science and Engineering A ; Volume 528, Issue 13-14 , 2011 , Pages 4422-4426 ; 09215093 (ISSN) Zare, A ; Ekrami, A ; Sharif University of Technology
    2011
    Abstract
    The strain hardening behavior of AISI 4340 steel with dual phase (DP) and triple phase (TP) microstructures with constant ferrite volume fractions of 34% was investigated. The microstructures of specimens were analyzed using an optical microscope. The tensile flow behavior of all the samples was explained using Holloman equation. Results showed that in both DP and TP steels, work hardening takes place in two stages. The onset strain of second stage of work hardening and Holloman equation parameters (work hardening exponent and strength coefficient) in both stages were increased with the increase of martensite volume fraction in TP steels. At first stage of work hardening, ferrite phase... 

    Influence of martensite volume fraction on tensile properties of triple phase ferrite-bainite-martensite steels

    , Article Materials Science and Engineering A ; Volume 530, Issue 1 , 2011 , Pages 440-445 ; 09215093 (ISSN) Zare, A ; Ekrami, A ; Sharif University of Technology
    2011
    Abstract
    This paper presents the effect of martensite volume fraction (VM) on mechanical properties of AISI 4340 steel with ferrite-bainite-martensite microstructures. The steel bars were austenitized at 900°C for 1h followed by intercritical annealing at 740°C for 100min and quenching into a salt bath with temperature of 300°C and holding at different times to obtain triple phase (TP) microstructures with 34vol.% fraction ferrite and various martensite (or bainite) contents. Presence of three phases in adjacent to each other was confirmed by metallographic analysis and TEM studies. TEM observation also indicates higher density of dislocations within ferrite near martensite colonies compared to that... 

    6DOF Flight Dynamics Modeling of a Flexible Flapping wing using Unsteady Aerodynamics

    , Ph.D. Dissertation Sharif University of Technology Zare, Hadi (Author) ; Pourtakdoust, Hossein (Supervisor)
    Abstract
    A complete 6DOF flight dynamic model of an elastic flapping wing (EFW), integrated with unsteady aerodynamic theory is developed. In this respect, initially efficient high fidelity modules for EFW structural dynamics (SD) as well as unsteady aerodynamics loadings (UAL) to be coupled with its flight dynamics are prepared. A modal approach is followed to model structural dynamics of plain and 3D EFWs. This is in contrast with the Euler-Bernoulli beam theory that is mostly utilized for SD in the existing literature. In addition, due to the possibility of large wing deformations as well as the existence of non-linear displacement regime for realistic EFW flights, non-linear modal approaches such... 

    Investigation on Interfacial Reactions in Aluminium to Copper Resistance Spot Welding

    , M.Sc. Thesis Sharif University of Technology Zare, Mohammad (Author) ; Pouranvari, Majid (Supervisor)
    Abstract
    With the development of electrical engineering and the electrical industry, the use of copper and its alloys has grown tremendously. On the other hand, with development and modern industry, it will be difficult to meet the requirements such as high performance, cost reduction and weight reduction of the structure if only one metal material is used in the production of the desired component or structure. Aluminum can be used in combination with copper because of its properties such as high thermal and electrical conductivity. Al/Cu bonding is used in industries such as microelectronics, automobiles and batteries. This study has investigated parametrically the feasibility of uneven bonding of... 

    A Fast Algorithm for Shadow Generation with Low Distortion Based on Shadow Map Technique

    , M.Sc. Thesis Sharif University of Technology Zare, Ehsan (Author) ; Jamzad, Mansour (Supervisor)
    Abstract
    Shadows are one of the most important details in graphical images. There exist many shadow generation algorithms each of which suffers from some problems. High processing time and ill-shaped shadow borders, known as alasing, are some of such problems. In this paper, we propose a heuristic method based on standard shadow map technique, named rotated shadow maps, to generate excellent hard shadows. Our method uses some shadow maps which are generated from the same view but objects are slightly rotated around the center of view area. Rotated shadow maps can be considered as an independent hard shadow generation algorithm. Also it can be combined with other shadow map based approaches. Utilizing... 

    Design of viscous fluid passive structural control systems using pole assignment algorithm

    , Article Structural Control and Health Monitoring ; Vol. 21, issue. 7 , July , 2014 , p. 1084-1099 Zare, A. R ; Ahmadizadeh, M ; Sharif University of Technology
    2014
    Abstract
    A methodology is developed for the design of optimum viscous fluid passive energy dissipation systems using pole assignment active control algorithm. In this method, the procedure to assign the new structural poles is slightly modified such that the resulting structural properties (i.e., the optimum locations of system poles) can be achieved merely by modification of structural stiffness and addition of a passive control system. A combination of stiffness reduction and increase of damping is utilized to reduce both acceleration and displacement response. It is shown that the control systems designed using this method provide structural performances slightly better than or close to those of... 

    Design of passive viscous fluid control systems for nonlinear structures based on active control

    , Article Journal of Earthquake Engineering ; 2017 , Pages 1-22 ; 13632469 (ISSN) Zare, A. R ; Ahmadizadeh, M ; Sharif University of Technology
    2017
    Abstract
    A practical procedure is developed for the design of passive control systems using viscous fluid dampers for nonlinear structures. The design methodology takes advantage of the modification of the damping, strength, and stiffness properties of the structure to achieve the desired relative displacement and absolute acceleration response. For this purpose, a study of poles in the complex plane is used to determine the required changes in the dynamic properties of nonlinear structures. Furthermore, a relatively simple relation between the ductility demands of highly damped single- and multiple-degree-of-freedom (SDF and MDF respectively) systems is established to reduce the computational burden... 

    Modified sliding mode design of passive viscous fluid control systems for nonlinear structures

    , Article Engineering Structures ; Volume 162 , 1 May , 2018 , Pages 245-256 ; 01410296 (ISSN) Zare, A. R ; Ahmadizadeh, M ; Sharif University of Technology
    Elsevier Ltd  2018
    Abstract
    A strategy is developed for design of passive control systems for structures experiencing inelastic deformations during earthquake loading. Besides the addition of passive energy dissipation devices, the proposed method suggests the required changes to the stiffness and strength of the structure, to reduce the absolute acceleration and relative deformation responses simultaneously. For this purpose, the locations and amounts of modifications in stiffness, strength and damping are determined by a sliding mode control algorithm to consider the nonlinear behavior of the structure. Being originally designed for active control, the sliding mode algorithm is modified to facilitate the extraction... 

    Design of passive viscous fluid control systems for nonlinear structures based on active control

    , Article Journal of Earthquake Engineering ; Volume 23, Issue 6 , 2019 , Pages 1033-1054 ; 13632469 (ISSN) Zare, A. R ; Ahmadizadeh, M ; Sharif University of Technology
    Taylor and Francis Ltd  2019
    Abstract
    ABSTARCT: A practical procedure is developed for the design of passive control systems using viscous fluid dampers for nonlinear structures. The design methodology takes advantage of the modification of the damping, strength, and stiffness properties of the structure to achieve the desired relative displacement and absolute acceleration response. For this purpose, a study of poles in the complex plane is used to determine the required changes in the dynamic properties of nonlinear structures. Furthermore, a relatively simple relation between the ductility demands of highly damped single- and multiple-degree-of-freedom (SDF and MDF respectively) systems is established to reduce the... 

    Design of a HEV’s Controller Using Learning-based Methods

    , M.Sc. Thesis Sharif University of Technology Zare, Aramchehr (Author) ; Boroushaki, Mehrdad (Supervisor)
    Abstract
    Hybrid electric vehicles (HEV) are proving to be one of the most promising innovations in advanced transportation systems to reduce air pollution and fossil fuel consumption. EMS is one of the most vital aspects of the HEV powertrain system. This research aims to design an optimal EMS under the condition of meeting the goals of drivability control, fuel consumption reduction, and battery charge stability. The current EMS is based on the classical rule-based method derived from fuzzy logic, which guides to the suboptimal solution in episodic driving cycles. Previous experiences in implementing Reinforcement Learning (RL) suffer from late convergence, instability in tracking the driving... 

    Helical motion wound-rotor resolver

    , Article IEEE Sensors Journal ; Volume 22, Issue 10 , 2022 , Pages 9371-9377 ; 1530437X (ISSN) Zare, F ; Nasiri Gheidari, Z ; Sharif University of Technology
    Institute of Electrical and Electronics Engineers Inc  2022
    Abstract
    In this paper an integrated core, high reliability, linear-rotational resolver with a simple slotless configuration is proposed. The moving part of the proposed resolver has only one helical winding. While, its stator needs at least two individual windings to be able to determine the linear and angular position in simultaneous linear and rotational, helical, motions. Three different configurations are proposed for the stator's windings: (1) helical and horizontally skewed winding (2) helical and vertically skewed winding (3) horizontally and vertically skewed windings. The influence of the mentioned configurations is discussed in the terms of sensor's accuracy in independent and simultaneous... 

    Winding function model for predicting performance of 2-DOF wound rotor resolver

    , Article IEEE Transactions on Transportation Electrification ; Volume 8, Issue 2 , 2022 , Pages 2062-2069 ; 23327782 (ISSN) Zare, F ; Nasiri Gheidari, Z ; Sharif University of Technology
    Institute of Electrical and Electronics Engineers Inc  2022
    Abstract
    Two-degree-of-freedom (2-DOF) electrical machines require position sensors for their motion control. In comparison with using two independent sensors, using a 2-DOF sensor enhances the closed-loop control system's performance. However, due to the 3-D structure of the 2-DOF sensor, its performance evaluation needs 3-D analysis. Also, due to helical motion the accuracy deterioration of the sensor, under mechanical faults needs more attention. Although the finite element method (FEM) is the best way to simulate such sensors, most of the commercial packages for transient finite element simulations are not able to consider two separate motions simultaneously. Furthermore, FEM has a high... 

    Plasma actuator effects on the flow physics of dynamic stall for a vertical axis wind turbine

    , Article Physics of Fluids ; Volume 34, Issue 7 , 2022 ; 10706631 (ISSN) Zare Chavoshi, M ; Ebrahimi, A ; Sharif University of Technology
    American Institute of Physics Inc  2022
    Abstract
    Darrieus type vertical axis wind turbines have several advantages over other wind turbines for local electricity generation in urban environments. However, the main aerodynamic challenge is the negative impacts of the dynamic stall phenomenon on the turbine performance. This study numerically scrutinizes the effects of plasma actuators on the dynamic stall control and performance improvement of a Darrieus turbine. For this sake, unsteady Reynolds-averaged Navier-Stokes equations are solved using a pressure-based finite volume method. The Suzen-Hoang plasma actuator model is employed to calculate the body forces attributed to the plasma actuator. First, the dynamic stall characteristics of... 

    Improving the performance of helical motion resolver based on accurate modelling of longitudinal end effect

    , Article IET Electric Power Applications ; Volume 16, Issue 10 , 2022 , Pages 1212-1222 ; 17518660 (ISSN) Zare, F ; Nasiri Gheidari, Z ; Sharif University of Technology
    John Wiley and Sons Inc  2022
    Abstract
    Using multiple position sensors in the control system of Two-Degrees of Freedom (2-DOF) motors causes it more complicated than that of conventional 1-DOF ones. However, employing a 2-DOF position sensor in comparison with two independent sensors, reduces the complexity, mass and volume of the system. The common 2-DOF sensors are able to determine the position in linear, rotational, and helical motion. Yet, they suffer from accuracy reduction due to the longitudinal end effect. Therefore, analytical modelling and the relevant compensation methods are discussed. The accuracy of the model is approved by comparing its results with those of 3D time transient finite element method. Afterwards, the... 

    Investigating The Transformation Of Strain-Induced Martensite During Deformation and its Effect on the Wear Behavior of Austenitic Stainless Steel

    , M.Sc. Thesis Sharif University of Technology Zare, Mahdi (Author) ; Serajzadeh, Siamak (Supervisor)
    Abstract
    In austenitic stainless steel types 304 and 316, due to the instability of the austenite phase, the martensite phase is formed by plastic deformation below the Md temperature. In this research, the cold rolling of 304L austenitic stainless steel and the transformation of austenite to strain-induced martensite and its effect on mechanical properties, especially wear, were studied. In this way, the samples were rolled in two modes and four passes in each mode. In the first case, the samples were cooled between each pass in water as a cooling liquid, and in the second case, the samples were cooled in each pass without using water and by air. Next, tests such as hardness measurement, uniaxial... 

    The Effect of Altering the Electrolyte and Electrodes Composition on the Electrochemical Performance of Water In Salt Electrolytes in Calcium-Ion Batteries

    , M.Sc. Thesis Sharif University of Technology Zare, Bahar (Author) ; Sadrnezhad, Khatiboleslam (Supervisor)
    Abstract
    This current research has focused on investigating and enhancing the performance of calcium-ion aqueous batteries in two phases, beginning with the selection of calcium ion as the charge transfer agent. The first phase entails determining the appropriate composition and concentration of salt containing calcium ions in the electrolyte, as well as assessing the feasibility of adding a second component salt to aqueous electrolytes. After conducting investigations including conductometric tests, Raman spectroscopy, and drawing analysis diagrams depicting increased capacity in terms of voltage (dQ/dV vs. V), it was determined that the electrolyte consisting of water and calcium nitrate (Ca(NO3)2)...