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hemmati-golsefidi--atefeh
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A robust optimization approach for the production-inventory-routing problem with simultaneous pickup and delivery
, Article Computers and Industrial Engineering ; Volume 143 , May , 2020 ; Akbari Jokar, M. R ; Sharif University of Technology
Elsevier Ltd
2020
Abstract
The production routing problem (PRP) merges the lot-sizing problem and the vehicle routing problem, two classical problems that have been the focus of comprehensive studies for over half a century. Solving the PRP is an effort to optimize decisions about the production, inventory, distribution, and routing in an integrated manner. In the literature of the recent decade, due to economic changes and regulatory issues, reverse logistics has become a focal point. Subsequently, the vehicle routing problem with simultaneous pickup and delivery (VRPSPD) has drawn more and more attention for its considerable effect on the reverse logistics problem. In addition, one of the major arguments in supply...
Integration of Production-inventory-routing Problem with Simultaneous Pickup and Delivery and Robust Optimization Approach
, M.Sc. Thesis Sharif University of Technology ; Akbari Jokar, Mohammad Reza (Supervisor)
Abstract
PRP is a combination of two classic problems. First one is the lot-sizing and the second one is vehicle’s routing which have been studied for more than fifty years. The prp is solved in attempt to jointly optimize production, inventory, distribution, routing decision and as a result, it is a inventory-routing problem as a whole. Despite the fact that prp involves a complex instructor, both universities and industries have been so eager to this problem since last decade. In this thesis an integrated assessment of PRP and various technics for solving the problem have been discussed. Moreover, taking into account the structure, hypothesis, and the constraints of the problem, a...
Survey and synthesis of zeolite adsorbents in Olefins and Paraffinssorption
, M.Sc. Thesis Sharif University of Technology ; Soltanieh, Mohammad (Supervisor)
Abstract
Olefin/ paraffin separation is one of the most important processes in the petrochemical industries.In the last decades, adsorption and membrane processes are a new technology considered significantly for this purpose. In order to synthesizeof zeolite powder (pure silica zeolite STT and CHA), raw materials were made by two methods and their HNMR spectrum was recorded and thenzeolite powder was synthesized. X ray diffraction(XRD) and scanning electron microscopy (SEM) images were taken,showing the same results as the refference structure.To consider synthesized zeolite powdersand olefin/ paraffin interactions, surface adsorption ofthose gases was accomplished on two zeolite powders. After...
Dynamics of Protein-Embedded Vesicles in Simple Shear Flow
, M.Sc. Thesis Sharif University of Technology ; Jalali, Mir Abbas (Supervisor) ; Khoshnood, Atefeh (Co-Advisor)
Abstract
Studying the dynamics of vesicles in simple shear flow is the first step to decipher the dynamics of cells in flows or the motion of vesicle-based nanoparticles in vessels for drug delivery. The deformation of vesicle in shear flow changes the permeability of its membrane and may lead to its rupture, both of which correlate with the transportation of vesicle cargos to their environment, especially important in drug delivery. The deformation of vesicles in shear flow not only depends on the physical properties of the whole system, such as temperature, but also on the mechanical properties of three media: vesicle membrane plus vesicle’s inner and outer fluid. The effect of the mechanical...
Oxidation of Sulfides and Olefins in the Presence of Nanocluster Polyoxotungstate–intercalated Layered Double Hydroxide Nanoparticles as a Catalyst
, M.Sc. Thesis Sharif University of Technology ; Bagherzadeh, Mojtaba (Supervisor)
Abstract
In this study, polyoxometalate (POM) intercalated in the layered double hydroxide (LDH) was synthesized by a selective ion-exchange method. For this purpose, the nanocluster [VW12O40]3- was immobilized on the Mg2+/A13+/Cl–LDH support. The heterogeneous catalyst was characterized by FT-IR, XRD, SEM and analysis of ICP. The LDH-POM was applied as a catalyst in efficient oxidation of sulfides to sulfoxides using UHP as oxidant and CH3OH/ CH¬2¬Cl¬2 ¬as a solvent at room temperature, as well as epoxidation of olefins using TBHP as an oxidants and C¬2H4Cl2 as a solvent in 84°C. This catalyst showed excellent catalytic activities for a substrate/catalyst ratio (200:1). For example, this catalytic...
Effects of Graphene Nanopores and Temperature on DNA Sequencing Using Molecular Dynamics
, M.Sc. Thesis Sharif University of Technology ; Meghdari, Ali (Supervisor) ; Khoshnood, Atefeh (Co-Advisor)
Abstract
Distinguishing the structure of DNA is of outmost importance in the medicine and agriculture industry nowadays. Various methods have been suggested so far; however, high costs, incorrect results, and time-taking process are among main defects of them. Scientists try to find new ways for recognizing DNA structure and system in order to overcome such problems. One of these new methods is absorbing and passing DNA through Nano-pores in an electrolyte solution under the influence of an electrical field. The basis of this method is the ionized currents which occur due to the passing of DNA through Nano-pores. Because each DNA base pairs can form a barrier corresponding to a unique measured value,...
Long Period Variable Stars in the Local Group Galaxies
, M.Sc. Thesis Sharif University of Technology ; Rahvar, Sohrab (Supervisor) ; Javadi, Atefeh (Co-Supervisor)
Abstract
In this thesis, the star formation history and evolution of IC 1613 dwarf galaxy and NGC 5128 giant elliptical galaxy has been studied. About IC 1613, our result shows that the star formation history of the galaxy is roughly constant in 5 Gyr ago and this support that the galaxy had been isolated at least in 5 Gyr ago. About NGC 5128, we can see that the star formation rate has suddenly increased in 700 Myr and 3.5 Gyr ago. This results in very good agreement with literature support that the galaxy has experienced some mergers with smaller gas rich galaxies
Study and Comparison the Incidence of Dutch Disease in Iranian Economy in Two Periods of Oil Shock
, M.Sc. Thesis Sharif University of Technology ; nili, Masoud (Supervisor) ; Madanizadeh, Ali (Supervisor)
Abstract
This paper studies and compares the effect of "Dutch disease" in Iranian economy in two periods of rising oil price (1973-1978) and (2004-2010). The study presents a DSGE model to analysis the behavior of economic variable in both periods and to address this question that whether or not policy maker has learning behavior. The model consists of households, final goods producers who divided in tradable goods and non-tradable goods sector and the government. I use calibration methods to estimate models parameters.Comparison of simulated results and the actual macroeconomic variables in Iran during 1338-1390 indicates that, first of all Dutch disease effect occur in both periods of oil shock so...
Ground Water Denitrification by Packed Bed Bioreactor With KMT Packing
, M.Sc. Thesis Sharif University of Technology ; Borghei, Mehdi (Supervisor)
Abstract
In this study biological denitrification method by moving bed biofilm reactor is investigated. The main advantage of MBBR reactor is due to their capacity for high removal rates and low operational problems such as clogging. Two MBBRs in series with 3 liter volume each, were designed in experimental set up and used in this research. Nitrification reactor worked under aerobic conditions and denitrification reactor operated under anaerobic conditions. Methanol was used as carbon source in the reactors throughout the study. Fifty percent of each reactor volume was occupied with KMT1 packing. To finding the optimum nitrate loading rate, the concentration of ammonium and nitrate were changed from...
Control of resistance spot welding using model predictive control
, Article 9th International Conference on Electrical and Electronics Engineering, 26 November 2015 through 28 November 2015 ; 2015 , Pages 864-868 ; 9786050107371 (ISBN) ; Haeri, M ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2015
Abstract
Nowadays, the need for industrial processes with sufficient accuracy, efficiency, and flexibility to compete world markets is inevitable. On the other hand, the advent of control techniques and increased computation power of CPUs allow implementation of complex controllers using optimization techniques to provide higher efficiency and economic productivity. Model predictive control refers to a wide range of optimization-based control methods applying explicit models to predict its prospective use. These methods of control compute control signal by minimizing the cost function so that the process output becomes very close to the optimal path. In this paper, we use a new model predictive...
Self-reconfiguration in highly available pervasive computing systems
, Article Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics), 23 June 2008 through 25 June 2008, Oslo ; Volume 5060 LNCS , 2008 , Pages 289-301 ; 03029743 (ISSN) ; 3540692940 (ISBN); 9783540692942 (ISBN) ; Jalili, R ; Sharif University of Technology
2008
Abstract
High availability of software systems is an essential requirement for pervasive computing environments. In such systems self-adaptation, using dynamic reconfiguration is also a key feature. However, dynamic reconfiguration potentially decreases the system availability by making parts of the system temporary frozen, especially during incomplete or faulty execution of the reconfiguration process. In this paper, we propose Assured Dynamic Reconfiguration Framework (ADRF), consisting of run-time analysis phases, assuring the desired correctness and completeness of dynamic reconfiguration process. We also specify factors that affect availability of reconfigurable software in pervasive computing...
Processing algorithm for a strapdown gyrocompass
, Article Scientia Iranica ; Volume 19, Issue 3 , 2012 , Pages 774-781 ; 10263098 (ISSN) ; Massoumnia, M. A ; Sharif University of Technology
2012
Abstract
The problem of gyrocompassing using inertial sensors, i.e., gyros and accelerometers, is addressed. North finding, with an order of accuracy of one arc-min, is not only required for the initial alignment of inertial navigation systems, but also has a critical role to play in the guidance and navigation of ships that navigate for long periods of time. In this work, after extracting the error model of an inertial navigation system and augmenting it with the error model of inertial sensors, a processing algorithm based on the Kalman filter is designed and simulated to process the navigation system velocity error, and to estimate and correct tilt and heading errors along with gyro drifts and...
Identification of Damage Type and Location in Reinforced Concrete Piers of Slab– Beam Bridges Using Numerical Methods
, M.Sc. Thesis Sharif University of Technology ; Ahmadizadeh, Mahdi (Supervisor)
Abstract
Bridges are among the crucial elements of transportation networks, and play an important role in facilitating emergency relief efforts following earthquakes. For this reason, it is emparative to monitor their damages to ensure about their performace in earthquakes. The structure of a bridge is divided into two parts, namely the superstructure and substructure. Due to the relatively high rigidity and strength of superstructures, most of structural damage is usually concentrated in substructures, which may ultimately affect the overall stability of the bridge. Therefore, assessing the level of damage in the substructure is of utmost concern. This research attempts to evaluate the damage in the...
Manipulation of Electronic Structure in Boron Nitride Nanosheets to Improve Catalytic and Photocatalytic Properties
, M.Sc. Thesis Sharif University of Technology ; Simchi, Abdolreza (Supervisor)
Abstract
The variety of 2D materials and their wide range of properties, as well as numerous methods to manipulate them, have made this class of materials among prominent candidates for the future of the energy industry. Among the means available to tailor nanomaterials performance for such applications, introducing dopants and the creation of heteroatom-doped structures are of great interest. In this study, mixtures of urea, boric acid, and graphene oxide, as cheap and available precursors, were used to synthesize C-doped h-BN nanosheets. After the implementation of TGA/DSC to select a suitable calcination temperature of 950 C°, the samples were successfully synthesized with relatively precise...
Evaluation of ascorbic acid-loaded calcium phosphate bone cements: Physical properties and in vitro release behavior
, Article Ceramics International ; Vol. 40, issue. 3 , April , 2014 , pp. 3961-3968 ; ISSN: 02728842 ; Hesaraki, S ; Nemati, A ; Sharif University of Technology
2014
Abstract
In this study, different concentrations of ascorbic acid (50, 100 and 200 μg/mL) were added to the liquid phase of a calcium phosphate cement (CPC). The cements were immersed in simulated body fluid (SBF) for different intervals and physical, physicochemical and mechanical properties of them were evaluated. The release of added ascorbic acid from CPCs into the SBF solution was also studied. From the results, both setting time and injectability of CPC decreased by adding ascorbic acid, however the compressive strength was sharply increased before soaking in SBF solution. But, the compressive strength values of all cements (with or without ascorbic acid) soaked in SBF solution for more than 7...
System modeling and optimization for islanded micro-grid using multi-cross learning-based chaotic differential evolution algorithm
, Article International Journal of Electrical Power and Energy Systems ; Vol. 56 , 2014 , pp. 349-360 ; ISSN: 01420615 ; Amjady, N ; Ehsan, M ; Sharif University of Technology
2014
Abstract
This paper presents a comprehensive operation model for micro-grids (MG) operating in the islanded mode. Various energy sources of a MG including diesel engine generator, micro-turbine, wind turbine and photovoltaic cell as well as battery storage and AC/DC rectifier/inverter are modeled in the proposed framework. Fuel costs, emission costs, and operation and maintenance (O&M) costs of these sources as well as their operating limits and characteristics are considered in the model. Furthermore, a new multi-cross learning-based chaotic differential evolution (MLCDE) algorithm is presented to solve the optimization problem of MG operation. The numerical results obtained from the proposed...
On the convergence of heterogeneous reinforcement learning private agents to nash equilibrium in a macroeconomic policy game
, Article Australian Journal of Basic and Applied Sciences ; Volume 5, Issue 7 , 2011 , Pages 491-499 ; 19918178 (ISSN) ; Nili, M ; Sadati, N ; Sharif University of Technology
2011
Abstract
A repeated inflation-unemployment game within the linear-quadratic frame-work of Barro and Gordon is studied assuming that the government would like to cheat optimally and the finite heterogeneous population of private agents attempts to learn the government's targets using a reinforcement learning algorithm. Private agents are heterogeneous in their initial expectations of inflation rate but are assumed to utilize an identical anticipatory reinforcement learning process, namely Q-learning. In our heterogeneous setting, the only way for the private agents to achieve a zero value for their loss function, is for all of them to correctly anticipate the Nash equilibrium. It is of particular...
Application of Worm-Like Micelles for Heavy Oil Recovery: Experimental and Modeling
, M.Sc. Thesis Sharif University of Technology ; Ghaznafari, Mohammad Hossein (Supervisor)
Abstract
Surfactants are widely used in enhancing oil recovery. But application of worm-like micelles which seem to be a perfect candidate for enhancing heavy oil recovery have been less studied despite their significant ability in reducing interfacial tension and their high viscosity. This research consists of three parts. In the first part, the kinetic and equilibrium adsorption of surfactant on reservoir rock is experimentally investigated, and its appropriate kinetic and equilibrium adsorption model is specified. According to the adsorption models, the pseudo second order kintic coefficient of adsorption is proved to have a linear relationship with concentration, so its value at different...
Reinforcement learning of heterogeneous private agents in a macroeconomic policy game
, Article Lecture Notes in Economics and Mathematical Systems ; Volume 645 , 2010 , Pages 215-226 ; 00758442 (ISSN) ; 9783642139468 (ISBN) ; Nili, M ; Sadati, N ; Sharif University of Technology
2010
Abstract
A repeated inflation-unemployment game within the linear-quadratic framework of Barro and Gordon is studied assuming that the government would like to cheat optimally and the finite heterogeneous population of private agents attempts to learn the government's targets using a reinforcement learning algorithm. Private agents are heterogeneous in their initial expectations of inflation rate but are assumed to utilize an identical anticipatory reinforcement learning process, namely Q-learning. In our heterogeneous setting, the only way for the private agents to achieve a zero value for their loss function, is for all of them to correctly anticipate the Nash equilibrium. It is of particular...
Towards a bounded-rationality model of multi-agent social learning in games
, Article 2010 10th International Conference on Intelligent Systems Design and Applications, ISDA'10, Cairo, 29 November 2010 through 1 December 2010 ; 2010 , Pages 142-148 ; 9781424481354 (ISBN) ; Sadati, N ; Nili, M ; Sharif University of Technology
2010
Abstract
This paper deals with the problem of multi-agent learning of a population of players, engaged in a repeated normal-form game. Assuming boundedly-rational agents, we propose a model of social learning based on trial and error, called "social reinforcement learning". This extension of well-known Q-learning algorithm, allows players within a population to communicate and share their experiences with each other. To illustrate the effectiveness of the proposed learning algorithm, a number of simulations on the benchmark game of "Battle of Sexes" has been carried out. Results show that supplementing communication to the classical form of Q-learning, significantly improves convergence speed towards...