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goodarzi--hamed
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An efficient tabu search algorithm for the single row facility location problem [electronic resource]
, Article European Journal Of Operational Research ; Vol. 205, No. 1, pp. 98-105 ; Eshghi, Kourosh ; Sharif University of Technology
Abstract
The general goal of the facility layout problem is to arrange a given number of facilities to minimize the total cost associated with the known or projected interactions between them. One of the special classes of the facility layout problem is the Single Row Facility Layout Problem (SRFLP), which consists of finding an optimal linear placement of rectangular facilities with varying dimensions on a straight line. This paper first presents and proves a theorem to find the optimal solution of a special case of SRFLP. The results obtained by this theorem prove to be very useful in reducing the computational efforts when a new algorithm based on tabu search for the SRFLP is proposed in this...
Sensitivity analysis of matching pennies game [electronic resource]
, Article Mathematical and Computer Modelling ; Volume 51, Issues 5–6, March 2010, Pages 722–735 ; Eshghi, Kourosh ; Sharif University of Technology
Abstract
In this paper, we have discussed the results of sensitivity analysis in a payoff matrix of the Matching Pennies game. After representing the game as a LP model, the sensitivity analysis of the elements of the payoff matrix is presented. The game value and the optimal strategies for different values of parameters are determined and compared
Task migration in mesh NOCs over virtual point-to-point connections
, Article 19th International Euromicro Conference on Parallel, Distributed, and Network-Based Processing, PDP 2011, Ayia Napa, 9 February 2011 through 11 February 2011 ; 2011 , Pages 463-469 ; 9780769543284 (ISBN) ; Sarbazi Azad, H ; Sharif University of Technology
2011
Abstract
Processor allocation in todays many core MPSoCs is a challenging task, especially since the order and requirements of incoming applications are unknown during design stage. To improve network performance, balance the workload across processing cores, or mitigate the effect of hot processing elements in thermal management methodologies, task migration is a method which has attracted much attention in recent years. Runtime task migration was first proposed in multicomputer with load balancing as the major objective. However, specific NoC properties such as limited amount of communication buffers, more sensitivity to implementation complexity, and tight latency and power consumption constraints...
The Static and Dynamic Relationship between Monetary and Multidimensional Poverty Approaches
, M.Sc. Thesis Sharif University of Technology ; Fatemi Ardestani, Farshad (Supervisor)
Abstract
The identification of the poor and the elimination of their poverty always has been the subject of discussion among researchers and policymakers. Today, most researchers consider poverty as a multidimensional phenomenon, and in addition to income indicator, it has indicators related to the level of knowledge, awareness, well-being and the health of individuals. The study of multidimensional poverty and the search for the discovery of its static and dynamic relationship with income-based poverty is the subject of this research. The analysis shows that both statically and dynamically, there is a substantial mismatch in the identification of the poor households according to these two...
Task migration in mesh NOCs over virtual point-to-point connections
, Article Proceedings - 19th International Euromicro Conference on Parallel, Distributed, and Network-Based Processing, PDP 2011 ; 2011 , p. 463-469 ; ISBN: 9780769543284 ; Sarbazi-Azad, H ; Sharif University of Technology
2011
Abstract
Processor allocation in todays many core MPSoCs is a challenging task, especially since the order and requirements of incoming applications are unknown during design stage. To improve network performance, balance the workload across processing cores, or mitigate the effect of hot processing elements in thermal management methodologies, task migration is a method which has attracted much attention in recent years. Runtime task migration was first proposed in multicomputer with load balancing as the major objective. However, specific NoC properties such as limited amount of communication buffers, more sensitivity to implementation complexity, and tight latency and power consumption constraints...
Propagation of SH Wave in Elastic Media with Cylindrical Inhomogeneity at Micro and Nano Scales by Couple Stress Theory
, M.Sc. Thesis Sharif University of Technology ; Mohammadi Shodja, Hossein (Supervisor)
Abstract
It is well known that the classical continuum theory does not consider size effect in predicting material’s behavior, however at the micro and nano scales, this effect is not negligible and the classical theory has deficiencies at these scales. To take into account the size effect, higher order continuum theories introduce new material constants into the formulation. One famous version of these theories is couple stress which is applied in this research. This theory considers size effect of inhomogeneity by employing Characteristic length of materials. Quasi-static couple stress and classical dynamic approaches do not include explicitly the size of the material unit cell in the formulation...
Evaluation of Performance and Power Consumption of the Task Migration Schemes in the Mesh NoC
, M.Sc. Thesis Sharif University of Technology ; Sarbazi Azad, Hamid (Supervisor)
Abstract
With the advance of the semiconductor technology, it has been feasible now to fabricate high performance multiprocessor systems-on-chips, containing tens and in the near future hundreds of processing cores. Meanwhile, the diminished technology feature size and high power consumption limit in using previous communication structures such as shared buses. Networks-on-Chip (NoC) have been introduced to obviate these constraints by providing high modularity, scalability and inherent parallelism. Design of these interconnect structures includes multiple tradeoffs between delays, throughput, energy consumption and silicon area requirements. So far, many mechanisms have been proposed to improve the...
Resistance spot welding of MS1200 martensitic advanced high strength steel: microstructure-properties relationship
, Article Journal of Manufacturing Processes ; Volume 31 , 2018 , Pages 867-874 ; 15266125 (ISSN) ; Sobhani, S ; Goodarzi, F ; Sharif University of Technology
Elsevier Ltd
2018
Abstract
This paper addresses the microstructure and tensile-shear mechanical performance of MS1200 Giga-grade martensitic advanced high strength steel resistance spot welds. The key phase transformations in MS1200 welds were lath martensite formation in the fusion zone (FZ) and upper-critical heat affected zone (HAZ), new ferrite formation in the inter-critical HAZ and martensite tempering in the sub-critical HAZ. The MS1200 welds were featured by a near matching hardness in the fusion zone and under-matching hardness in the heat affected zone (HAZ) compared to the base metal. At certain process window a complete nugget pullout and separation was observed with high post-necking tearing energy. The...
Design of Steam Turbine Control Valves Seat on Site Machinning Robot
, M.Sc. Thesis Sharif University of Technology ; Durali, Mohammad (Supervisor)
Abstract
Designing a part of an on site repair system for refurbishing steam turbine high pressure control valve has been done in this project. The main role of this control valve is to control the input flow to the turbine in different working condition . However, due to high temperature and pressure, the seat is exposed to erosion. R epairing this part in workshop requires great amount of time and cost, because the valve is a part of the turbine body and must be cut and rewelded to the turbine body. S o using an on-site repair method is highly needed. In addition, due to the limited visibility and access to the valve seat, and accurate...
Coordinated Strategy of Price-maker Renewable Generation and Thermal Units in Elrctricity Market
, M.Sc. Thesis Sharif University of Technology ; Ranjbar, Ali Mohammad (Supervisor)
Abstract
Wind energy, as a type of renewable energy resource, is clean and is rapidly growing globally. The intermittency in the production of wind energy is the most major obstacle for these producers in a competitive electricity market, to compete with thermal units. Most existing models in the literature mitigate the risk of wind power, by coordinating them with energy storages such as pumped storages power plant. Here, in this thesis, another risk mitigation approach is introduced which combines wind energy and natural gas power plant in an electricity market. In addition, as the penetration level of wind power grows, the wind power producers must be considered as a price-maker player which their...
Course Scheduling Problem in Sharif University of Technology
, M.Sc. Thesis Sharif University of Technology ; Salmasi, Naser (Supervisor)
Abstract
This study strives to solve the course scheduling problem based on the constraints in Sharif University. In course scheduling problem, first we need to assign each course to a professor (This is done according to professors’ preferences in Sharif University) then we assign each course to a classroom and a time slot subject to professors, classrooms and time constraints (For example no two courses can be assigned to the same classroom at the same time slot). If solved manually, the solving process will take several days and at best results in a feasible solution. The education department is responsible for scheduling 661courses in five days a week and assigning them to 56 classrooms...
Control of DFIG-Based Wind Generation to Improve Inter-area Oscillation Damping
, M.Sc. Thesis Sharif University of Technology ; Ranjbar, Ali Mohammad (Supervisor)
Abstract
Low-frequency oscillation damping in power system is main determinants of the stability of the system. According to increasing of wind farms with high penetration levels in the power system, participation and control of wind farms for increase damping inter area oscillations seems important. In this study a damping controller suggested for Doubly Fed Induction Generator (DFIG). Using this controller and only available local signal as input controller and combination of both active and reactive power modulation, can greatly increase damping inter area oscillations and stability of uncertainty and different working points. Using linear analysis system, identified modes oscillating system and...
Direct yaw moment controller design for vehicle dynamic control systems
, Article Proceedings of the IASTED International Conference on Modelling, Sumulation and Optimization, Banff, Alta., 2 July 2003 through 4 July 2003 ; 2003 , Pages 120-124 ; 0889863725 (ISBN) ; Naderkhani, B ; Esmailzadeh, E ; Sharif University of Technology
2003
Abstract
Direct yaw moment control (DYMC) is one of the most effective method that improves not only the directional stability of the vehicles but also their road handling and controllability to a great extent. In this method by developing a difference in the longitudinal force (often the braking force) on two sides of the vehicle, an external stabilizing yaw moment is applied to the vehicle. In this study, an optimal control law for DYMC is proposed. The control law is based on the yaw rate, the lateral velocity feedback, and the steering angle feedforward. Simulation results obtained indicate that considerable improvement in the vehicle dynamic behavior can be achieved when the optimal yaw moment...
Experimental and Simulation Study to Determine the Fracture Flow Functions in Two Phase Systems at Core Scale
, M.Sc. Thesis Sharif University of Technology ; Ghazanfari, Mohammad Hossein (Supervisor)
Abstract
Fractured reservoirs have allocated a significant portion of Iran's and the world's oil and gas reserves, underscoring the importance of predicting the performance of these reservoir types in the oil and gas industry. Predicting the performance of fractured reservoirs by professional reservoir simulators, especially in enhanced recovery conditions, requires precise information on fracture flow functions, which is often limited. These functions vary for each reservoir based on the distinct characteristics of the rock and fluid, and the only way to determine them is through appropriate laboratory experimentation and modeling of the results. Currently, in simulation models, the relative...
Optimal-Robust Control of Drug Delivery in Cancer Chemotherapy
, M.Sc. Thesis Sharif University of Technology ; Moradi, Hamed (Supervisor)
Abstract
Chemotherapy is a proven and effective systematic approach to treat various types of cancers. Despite its advantages, chemotherapy would kill healthy as well as cancer cells. To overcome this problem, different controlling strategies are implemented. This study aims to provide a medicine drug delivery schedule for chemotherapy (by designing a proper controlling system) based on the verifiable mathematical models. First, the dynamic model is analysed and stability points are reviewed. The selected model has five state variables and two inputs. In this study, the focus is on dynamic model analysis and obtaining an effective and appropriate treatment pattern by designing a proper controller. To...
Nonlinear Vibration Analysis of Non-Uniform Beam in two Lateral Directions by Multiple Scales Method: Application in Wind Turbine
, M.Sc. Thesis Sharif University of Technology ; Moradi, Hamed (Supervisor)
Abstract
Environmental issues and energy crisis have led the world attention to the renewable energies; especially wind power, since they have low cost and high reliability. One of the most challenging areas of studying for wind power is to increase the capacity of wind turbines. As a result, over the years, wind turbines have got progressively larger. Vibration is one of the problems that reduces the life and efficiency of wind turbines; and the growing size of the blades has worsen this problem due to the importance of nonlinear effects in large scale wind turbines. Researchers have been constantly working on this issue in order to make the wind turbines more efficient. In this research, a...
Robust Power Control of Wind Turbine with Smooth Switching between Operational Regions using a Two-mass Model
, M.Sc. Thesis Sharif University of Technology ; Moradi, Hamed (Supervisor)
Abstract
Wind turbines have been the subject of many researches in recent decades. Optimization and continuous improvement of these systems play a decisive role in the development and exploitation of wind farms. Wind turbines can be studied from several aspects such as structure, dynamics, aerodynamics, electricity and control. In this research, robust power control of the wind turbine has been studied with emphasis on accurate 2 DOF mechanical and aerodynamic modeling. Aerodynamic coefficients of the turbine have been calculated using the numerical methods and the effect of this numerical modeling has been studied in comparison with the analytical methods on the turbine power control. Several new...
Using Robust Control in Drug and Virus Scheduling in Chemovirotherapy Nonlinear Model
, M.Sc. Thesis Sharif University of Technology ; Moradi, Hamed (Supervisor)
Abstract
Best cancer treatment is the one which reduces the tumor density in minimum time and side effects, considering the input limitations. In this paper, tracking controller and robust controllers are designed to achieve the mentioned objectives, simultaneously. An ODE-based mathematical model of the human body under chemovirotherapy is selected, which includes the uninfected and infected tumor cells, free viruses, immune cells, and a chemotherapeutic drug. For tracking purposes, a servo controller based on the entire eigenstructure assignment (EESA) approach is applied to the model, continuously and discretely. For robust purposes H-infinity and D-K iteration approaches are implemented and...
Assessment of Seismic Retrofit Policies for Buildings
, M.Sc. Thesis Sharif University of Technology ; Kashani, Hamed (Supervisor)
Abstract
Occurrence of natural disasters such as earthquake could seriously damage most buildings especially those with insufficient resistance located in urban worn-out textures. In order to reduce unpleasant consequences of an earthquake, appropriate policies need to be considered to persuade the beneficiaries to follow retrofitting standards in the process of planning, designing, and construction of buildings. These policies shall be implemented through institutions in arbitrary or obligatory forms, by encouragement or penalty mechanisms. In order to consider these policies, first of all we need to identify the beneficiaries and their particulars. By studying and considering subjects discussed in...
Parametric study and computation of seismic performance factors of braced shear panels
, Article Scientia Iranica ; Volume 23, Issue 2 , 2016 , Pages 460-474 ; 10263098 (ISSN) ; Mofid, M ; Sharif University of Technology
Sharif University of Technology
2016
Abstract
By locating a steel shear panel on the intersection point of the X-braces, concentrically or eccentrically braced shear panel (CBFSP or EBFSP) is formed. In this paper, to perform parametric study, 1-story CBFSP and EBFSP models with span length greater or less than height are considered. Using linear static analyses, the effects of size and location of the shear panel on the lateral stiffness of the frame with respect to the moment resisting frame with the same member sections are investigated. Next, for 1- And 3-story models, maximum displacement, along with base shear, and the ratio between the dissipated energy and input energy are examined under 4 ground motion records. Behavior of the...