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samarghandi--h---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...
An efficient tabu algorithm for the single row facility layout problem
, Article European Journal of Operational Research ; Volume 205, Issue 1 , 2010 , Pages 98-105 ; 03772217 (ISSN) ; Eshghi, K ; Sharif University of Technology
2010
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...
An efficient tabu algorithm for solving the single row facility layoutproblem
, Article 2009 International Conference on Computers and Industrial Engineering, CIE 2009, 6 July 2009 through 9 July 2009, Troyes ; 2009 , Pages 482-488 ; 9781424441365 (ISBN) ; Eshghi, K ; Sharif University of Technology
2009
Abstract
Single-Row Facility Layout Problem (SRFLP) is a http://library.sharif.ir/web-manage/catalog/resource.do?method=edit&flowLastAction=view&id=447751special class of facilitylayout problems, consists of finding an optimal linear placement of rectangularfacilities with varying dimensions on a straight line. In this research, wefirst present a theorem to find the optimal solution of a special case of SRFLP.The results obtained by this theorem are very useful in reducing thecomputational efforts when, later on, a new algorithm based on tabu search ispresented for SRFLP. Computational results of the proposed algorithm onbenchmark problems show the efficiency of the algorithm compared to the...
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
A fast and reliable multi-sender algorithm for peer-to-peer networks
, Article Journal of Network and Computer Applications ; Volume 32, Issue 3 , May , 2009 , Pages 733–740 ; Sharif University of Technology
2009
Abstract
Due to special constraints in peer-to-peer (P2P) networks (such as bandwidth limitation) and because of their highly dynamic characteristics, a single node cannot provide a reliable multimedia stream to the receivers. Several multi-sender algorithms are proposed to reliably deliver a media stream to the receiver through the intrinsically unreliable P2P networks. Based on upload bandwidths and availability of peers as well as the bandwidths of the links connecting the senders and the receiver, PROMISE selects a set of active senders to maximize the expected bit-rate delivered to the receiver. By careful investigation of PROMISE, in this paper, we present why and how it deviates from finding...
Inclusion problems associated with thin fcc films: linkage between eigenstrain and inter-atomic potential
, Article Mechanics of Materials ; Volume 39, Issue 8 , 2007 , Pages 803-818 ; 01676636 (ISSN) ; Pahlevani, L ; Hamed, E ; Sharif University of Technology
2007
Abstract
Often, during fabrication of thin films on substrates, different types of defects may be introduced into the films. Recently, the determination of the elastic fields due to the self-assembly of quantum dots or strained islands in thin films has been of major concern. In the micromechanical studies, such strained islands are modeled by inclusions. This paper aims to develop a theory pertaining to the presence of nano-inclusions of various geometries within thin films having face centered cubic (fcc) structure. To this end, the notion of eigenstrain is combined with a many body inter-atomic potential suitable for fcc crystals. The interaction between atoms is modeled via Sutton-Chen (SC)...
Identification of external power system linear dynamic equivalents as MIMO feedback blocks for the study system
, Article International Journal of Emerging Electric Power Systems ; Volume 8, Issue 5 , 21 Nov. 2007 , 2007 ; 1553779X (ISSN) ; Ranjbar, A. M ; Lesani, H ; Radmanesh, H ; Sharif University of Technology
2007
Abstract
The necessity of dynamic equivalents for power system analysis has been well known since the expansion of large interconnected power networks, and has been discussed during the last decades. The present paper proposes a new method for constructing dynamic equivalents of power systems. In this method, at the first step the "study system" is modeled completely via a single machineinfinite bus modeling procedure. Then the "external system" is identified as a MIMO feedback block of this model in such a manner that can include dynamic effects of the latter on the behavior of the former. The method is successfully experimented on a part of the Iranian southern network. Copyright © 2007 The...
Separation of delamination modes in composite beams with symmetric delaminations
, Article Materials and Design ; Volume 27, Issue 10 , 2006 , Pages 900-910 ; 02613069 (ISSN) ; Nosier, A ; Farrahi, G. H ; Sharif University of Technology
Elsevier Ltd
2006
Abstract
Delaminated composite beam under general edge loading conditions is studied. Based on a technical engineering theory an analytical procedure for calculation of strain energy release rate and its separation into modes I and II of delamination is presented. By choosing a suitable displacement field based on second-order shear-thickness deformation theory and using the principle of minimum total potential energy, the equations of equilibrium are obtained along with the appropriate boundary conditions. The J integral and its definition for different modes of fracture is used for calculation of strain energy release rate and its separation into different modes. Double cantilever beam (DCB)...
Hot workability of ultrafine-grained aluminum alloy produced by severe plastic deformation of Al6063 powder and consolidation [electronic resource]
, Article Materials Science Forum ; Volume 667-669, 2011, Pages 979-984 ; Simchi, A. (Abdolreza) ; Seop Kim, Hyoung ; Sharif University of Technology
Abstract
Al6063 powder was subjected to severe plastic deformation via high-energy mechanical milling to prepare ultrafine-grained (UFG) aluminium alloy. Uniaxial compression test at various temperatures between 300 and 450 °C and strain rates between 0.01 and 1 s-1 was carried out to evaluate hot workability of the material. Microstructural studies were performed by EBSD and TEM. The average activation energy and strain rate sensitivity of the hot deformation process were determined to be 280 kJ mol-1 and 0.05, respectively. The deformation temperature and applied strain rate significantly affected the grain structure of UFG Al alloy. A finer grain structure was obtained at lower temperatures and...
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...
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...
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...
Modelling and Electromechanical Control of Variable Speed wind Turbine in Order to Gain Maximum Wind Power
, M.Sc. Thesis Sharif University of Technology ; Moradi, Hamed (Supervisor)
Abstract
In this research, the main purpose of the controller design is in the second region of operation of a wind turbine, which involves absorbing the maximum energy from the wind. WindPACT 1.5MW turbine has been investigated and the power coefficient of this turbine has been obtained using WT-PERF and FAST softwares. Simulations show that the results of both methods are well matched. Then, using ANFIS, a method for estimating the wind speed is derived from the data obtained by FAST. Inputs to the ANFIS system are the turbine aerodynamic power, rotor speed and blade pitch angle while the output of ANFIS system is the estimated wind speed. The maximum power coefficient of the wind turbine occurs...
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...
Laboratory Investigation of the Effects of Sodium Chloride Concentration on Soil Water Retention Curve and Volumetric behavior Using an Unsaturated Automatic Oedometer
, M.Sc. Thesis Sharif University of Technology ; Sadeghi, Hamed (Supervisor)
Abstract
Laboratory studies to investigate the effects of different saline concentrations (such as sodium chloride or calcium chloride) on the soil water retention behavior of clayey soils and their volumetric changes have received much attention recently. However, many previous studies have investigated these effects in only one path of the SWRC (wetting or drying path) and the effects of saline concentration on hydraulic hysteresis have not been considered. In addition, researchers have frequently studied these effects on SWRC on clay samples, and little research has been done on collapsible soils. Therefore, the most important purpose of this study is to investigate the effects of increasing...
Robust Optimal Control of Drug Delivery in Cancer Chemotherapy based on a New Realistic Dynamic Model of the Process
, M.Sc. Thesis Sharif University of Technology ; Moradi, Hamed (Supervisor)
Abstract
Today, cancer mortality is one of the most important problems, even considering the scientific advances that offer more effective solutions to treat some diseases, providing a way to prevent and treat this disease is one of the most important issues that engineers have considered. This is achieved by designing a controller to minimize the size of the cancer tumor population, increase healthy cells, optimize treatment time, and drug dose.To achieve this goal, pharmacokinetic, pharmacodynamic, tumor growth, and healthy cell growth models, and mathematical models for subsystems that affect tumor growth, such as the angiogenic system, have been studied to develop a single mathematical model. In...
Probabilistic Framework to Quantify the Resilience of Urban Gas Distribution Networks
, M.Sc. Thesis Sharif University of Technology ; Kashani, Hamed (Supervisor)
Abstract
This study proposes a probabilistic framework to quantify the seismic resilience of urban natural gas distribution networks. Infrastructure resilience is defined as the ability to maintain performance after a hazard or, in case of a loss of performance, return to the minimum desired level in the optimal time. The framework presented in this research is comprised of multiple interconnected probabilistic models. These models work in harmony to characterize the impact of the earthquake on various infrastructures such as the buildings and urban gas distribution network components, as well as the probable consequences of the earthquake. The post-earthquake recovery of the gas distribution network...
Machine Learning Models for Estimating House Prices
, M.Sc. Thesis Sharif University of Technology ; Kashani, Hamed (Supervisor)
Abstract
Optimal use of available resources for construction projects depends on proper decision-making on how to spend resources. Optimization of resource consumption should be done taking into account project revenue. In this regard, investors need a suitable mechanism to predict the selling price of the construction project and the resulting profit. Therefore, investors and stakeholders need a suitable model with the help of which they can make decisions such as choosing materials to guarantee the desired profit from the sale. This research will provide a framework for constructing models for estimating the price of residential units by considering some features of the building and some economic...