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ghader-tootoonchi--alireza
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Residential Energy Hub Management using Reinforcement Learning Methods
, M.Sc. Thesis Sharif University of Technology ; Moeini Aghtaie, Moein (Supervisor)
Abstract
In recent years, various studies have been conducted focusing on the optimization and scheduling of energy hubs (EH). EH optimization is important because it tries to create synergy in the energy supply system by considering the relationships between energy carriers. For this purpose, various algorithms such as analytical methods (linear programming) and evolutionary and heuristic algorithms have been used. Also, recently, various studies have addressed the applications of reinforcement learning for energy hub management. In this study, a hybrid model for energy hub management has been developed by combining classical linear models (Known as white-box models) and reinforcement learning...
Intelligent timetable evaluation using fuzzy AHP
, Article Expert Systems with Applications ; Volume 38, Issue 4 , 2011 , Pages 3718-3723 ; 09574174 (ISSN) ; Kanani, A ; Tootoonchi, M ; Afzali, H. R ; Sharif University of Technology
2011
Abstract
There is a substantial body of empirical literature that establishes the benefits of customer satisfaction for enterprises. Among different available options to present our service, selecting the best choice in the customers' eyes is a vital decision. Developing appropriate passenger train schedules is counted as one of the major managerial concerns in transportation environment. Although different algorithms have been developed to create predictive schedules for a fleet of passenger trains using different performance indicators, selecting the best one embraces some ambiguities and uncertainties. That is because a one-dimensional objective function may not be sufficient for responding...
Modeling the behavior of contending opportunistic cognitive radios
, Article 2007 IEEE International Conference on Signal Processing and Communications, ICSPC 2007, Dubai, 14 November 2007 through 27 November 2007 ; 2007 , Pages 720-723 ; 9781424412365 (ISBN) ; Ashtiani, F ; Hassani, S. H ; Tootoonchi, P ; Sharif University of Technology
2007
Abstract
In this paper, we propose a new model to evaluate the behavior of cognitive radios (CRs). In this model, we consider a specific number of primary users having independent probabilistic on-off behavior. In addition, a specific number of opportunistic cognitive radios in saturation mode is assumed. We consider contention for CRs in order to occupy an inactive primary channel independently according to a simple MAC scheme. Our model is based on a closed BCMP state-dependent queueing network. We map contention of the CRs and the behavior of primary users on suitable parameters of the queueing network. By solving the network, we obtain the steady state behavior of CRs, then we find the efficient...
New mathematical modeling of temperature-based properties of ionic liquids mixture: Comparison between semi-empirical equation and equation of state
, Article Chemical Engineering Research and Design ; Volume 177 , 2022 , Pages 331-353 ; 02638762 (ISSN) ; Bagheri, H ; Ghazvini, M ; Ghader, S ; Sharif University of Technology
Institution of Chemical Engineers
2022
Abstract
Ionic liquids are a significant type of organic salts with attractive and superior physicochemical features for employing in a number of chemical processes. Ionic liquids include one large and asymmetric cationic or anionic functional group. The properties of cationic functional group are almost similar and it is main motivation of this study. In the present investigation, we extended various semi-empirical correlations to predict some temperature-based properties of ionic liquids mixture (IL-mixture). These properties are density, viscosity, surface tension and bubble point pressure. In the case of IL-mixture density, modified Rackett equation and Taylor equation with three scenarios,...
Preparation of Calcium Phosphate Alumina Nano Biocomposites
, M.Sc. Thesis Sharif University of Technology ; Nemati, Ali (Supervisor) ; Behnam, Ghader (Supervisor)
Abstract
The purpose of this study was aimed to evaluate the effect of Alumina on the sintering, phase development, mechanical properties and biocompatibility of fluoridated hyroxyapatite sintered via conventional furnace and microwave assisted oven. Green compacts having 30wt% Alumina nanoparticles were sintered without pressure at various temperatures (1000-1400°C) for one hour in conventional furnace. Phase composition, thermal behavior and morphological analyses were performed using X-ray diffraction (XRD), simultaneous thermogravimetry and differential thermal analysis (STA), and Scanning Electron Microscopy (SEM), respectively. With the increase in temperature and the Alumina content, severe...
Graph-based Word Embedding Using Deep Neural Networks
, M.Sc. Thesis Sharif University of Technology ; Soleymani Baghshah, Mahdieh (Supervisor)
Abstract
Regarding the ever-increasing usage of text generation and analysis in Natural Language Processing field, Language Modeling and Masked Language Modeling have been recently one of the most frequent tasks. Besides, many pretrained models such as BERT have been proposed due to the lack of rich datasets and computational resources among researchers. These models can be finetuned on other datasets in downstream tasks. Although these Transformer-based deep neural networks have performed perfectly in many problems, they still have some shortcomings in a few tasks.Furthermore, structured data like graphs have been recently used extensively in Natural Language Processing and researchers have taken...
Ionic liquid excess molar volume prediction: a conceptual comparison
, Article Journal of Molecular Liquids ; Volume 336 , 2021 ; 01677322 (ISSN) ; Karimi, N ; Dan, S ; Notej, B ; Ghader, S ; Sharif University of Technology
Elsevier B.V
2021
Abstract
In this study, the prediction of excess molar volume of ionic liquid + solvent binary system is described using modified two-parameter and three-parameter cubic equation of state (CEoS). The studied binary systems are consisted of 41 ionic liquids, 40 solvents and 5293 data point in the wide temperature range (278.15–353.15 K), ionic liquid mole fraction (0.0036–0.9920) and atmospheric pressure i.e. P = 1 bar. At the first step, the volume-translated parameter (c) was obtained based on three linear, distance function and exponential-type temperature-dependent cases and using experimental pure density. After that, and due to easy-to-use of c-parameter, various formula was presented based on...
Comparison of Different Supply Chain Financing (SCF)Methods and their Impact on Financial and Operational Productivity of Companies in the Vegetable Oil Supply Chain in Iran
, M.Sc. Thesis Sharif University of Technology ; Sepehri, Mehran (Supervisor) ; Hajizadeh, Iman (Co-Supervisor) ; Tootoonchi, Mahshid (Co-Supervisor)
Abstract
In the contemporary world, especially after the financial crisis, the importance of financial flow and working capital management for companies has become more important than ever. There have been various ways to meet the financial needs of companies in the past. Financing methods such as giving capital from investors and receiving loan, from the past, to new methods such as supply chain financing, which have been the major part of financing researches since 2005.Conversely, companies interact together to meet the needs of end customers and thus form a supply chain in which the product / service of each company, input and raw material of the company Forms the next. This chain of...
Sintering Improvement of Nano Hydroxyapatite Bodies by Magnesium Incorporation and Using Microwave Sintering
, M.Sc. Thesis Sharif University of Technology ; Sadrnejhad, Khatiboleslam (Supervisor) ; Behnam Ghader, Ali Asghar (Supervisor)
Abstract
Magnesium is one of most important elements in bio hedroxyapatite. Magnesium effects on all stages of bone growth metabolism. Also increases bone’s osteoblastic and osteoclastic activities. That’s why incorporation of Mg ions into hudroxyapatite structure has become one of interesting fields for bone implants production. In addition Mg can improve sintering and mechanical properties of HAp. Thet’s why in this investigation the effect of incorporated Mg into HAp structure has been studied. Three kinds of powders have been prepared to perform this study. Pure HAp nano powder produced via sol-gel method, Mg contain HAp nano powder produced via sol-gel method and a mixture of nano HAp and nano...
Preparation of Nanocomposite Membrane For H2S / CH4 Separation
, M.Sc. Thesis Sharif University of Technology ; Mousavi, Abbas (Supervisor) ; Khanbabaee, Ghader (Supervisor) ; Babana’lbandi, Ahmad (Co-Advisor)
Abstract
Due to the presence of carbon dioxide and hydrogen sulfide in natural gas outlet of wells, it cannot be sent directly to the municipal pipelines. This study was trying to be select and made membranes for separation of CO2 and H2S from methane. Permeability of methane and carbon dioxide gases through the polyurethane membranes were studied. For this purpose, two commercial polyurethane and synthesized polyurethane with different formulations of the compounds that have been studied so far in the literature were used. Synthesized polyurethane and nano-composite membranes were characterized by using Scanning Electron Microscopy (SEM), Differential Scanning Calorimetry (DSC) and Fourier Transfer...
Rcci Curvature for Metric-Measure Space via Optimal Transport
, M.Sc. Thesis Sharif University of Technology ; Bahraini, Alireza (Supervisor) ; Ranjbar Motlagh, Alireza (Co-Advisor)
Abstract
One of the important questions in mathematics is generalized. In case of metric spaces, one of the questions is: Can we extend notions of Riemannian geometry to arbitrary metric spaces smoothly? Ricci curvature is one of the most important concepts in differential geometry. Ricci curvature is defined for the Riemannian manifold and has many applications in mathematics and physics like Einstein’s equation in relativity theory. There is a good notion for a metric space having “sectional curvature bounded below by K” or “sectional curvature bounded above by K”, due to Alexandrov. Can we define the concept of Ricci curvature in metric space? A motivation for this question comes from Gromov’s...
, M.Sc. Thesis Sharif University of Technology ; Khaloo, Alireza (Supervisor)
Abstract
Seismic design codes reduce loads by using response modification factor. Because of the reserved strength in structural elements and capacity of structure to dissipate energy, structures can be designed for lower seismic loads. This factor has modified over time. In this thesis, the effect of the reduction in behavior factor on the response of two kinds of reinforced concrete systems were evaluated. Moment resisting frames and dual systems with different heights and regularity in plan, heve been design according to the behavior factor which is recommended in the 3rd edition of the Iranian codes of practice for seismic resistance design of buildings (Standard No. 2800). Drift and...
Prediction of Financial Markets Using Combination of Artificial Intelligence and Technical Analysis
, M.Sc. Thesis Sharif University of Technology ; Haji, Alireza (Supervisor)
Abstract
Generally, nowadays, machine learning methods are used in many different areas for their superiority over other methods of prediction. Although being a tough task, stock market prediction with machine learning approaches is being spread due to satisfying results published ever yday. Machine learning methods usually use varied kinds of data ,including structured data such as market data, technical indicators and some fundamental data as well as unstructured one entailing text and graph data in order to enhance their predictability capacity. In this thesis we aimed to find out more about the importance and the contribution of structured data in prediction and we tried to attain a framework...
, M.Sc. Thesis Sharif University of Technology ; Hajji, Alireza (Supervisor)
Abstract
This thesis presents an inventory control system which is based on Meta-heuristic Algorithms.In this thesis we will optimize the input values of our tree-echelon inventory model (keeping costs,stock worth,reorder costs,...) with these Algorithms. The presented method is able to determine the optimal stock level, costs of system and number of shipments in the system. The method is basically a decision support system (DES) and it is able to provide the order scheduling parameters of goods at operational level. The aim of the current research is to demonstrate that a Meta-heuristic algorithmis capable of solving complex inventory problems and with future improvements it is able to achieve...
The Ricci Flow with Applications to the Poincare and Calabi Conjectures
, M.Sc. Thesis Sharif University of Technology ; Bahreini, Alireza (Supervisor)
Abstract
Poincare conjecture is one of the rst eorts for classifying 3-manifolds that was stated in the begining of 20th century. Eorts for proving this conjecture continued for about 100 years and nally Perelman has solved it in 2003. He has used Ricci ow which has been invented by Richard Hamilton in the early 80's. In this thesis rst we will introduce Ricci ow and will state the results before Perelman such as short time and long time existence of solution. Then we will mention some applications of Ricci ow and will state an explanation of the proof of uniformization and Calabi conjecture by Ricci ow. After that we start the main part of the thesis. In this part we will montion one of the...
Feasibility And Study(CNG Cylinder Production Plant)
, M.Sc. Thesis Sharif University of Technology ; Haji, Alireza (Supervisor)
Abstract
Nowadays best using of fossil fuels sources of the country (and) importance of comparison against lack of capacity in petrol production make determined the programmers and the directors to foresee and design expanded programs of the goals, to use natural gas for car fuels. To reach fulfillment of these programs, the confirmed needs of the natural gas cylinders are improved and make it essential to invest on producing compressive natural gas cylinders. In this way economical and technical change researches has been done in order to construct on department to produce 200,000 compressive natural gas cylinders in a year during two sets.(shifts) According to the results of technical researches...
Synthesis, Characterization and Field Emission Study of Molybdenum Oxide (MoOx)Nanostructures
, M.Sc. Thesis Sharif University of Technology ; Moshfegh, Alireza (Supervisor)
Abstract
Different molybdenum oxide nano/micro structure thin films were synthesized by thermal evaporation method under various growth conditions such as deposition time, temperature and evaporation source-substrate distance. Molybdenum oxide nanostructures grown on Si(100) such as nanowalls, nanostars and nanowires were characterized with scanning electron microscopy (SEM), x-ray photoelectron spectroscopy (XPS), x-ray diffraction (XRD), atomic force microscopy (AFM) and high resolution transmission electron microscopy (HRTEM). Shape and type of nanostructures were determined with SEM, AFM and HRTEM analysis. XPS analysis showed that the synthesized nanostructures contained Mo6+, Mo5+, Mo4+ and...
Identification and Abnormal Condition Detection of a Cement Rotary Kiln
, M.Sc. Thesis Sharif University of Technology ; Fatehi, Alireza (Supervisor)
Abstract
One of the most important parts of a cement factory is the cement rotary kiln which plays a key role in quality and quantity of produced cement. In this part, the physical exertion and bilateral movement of air and materials, together with chemical reactions take place. Thus, this system has immensely complex and nonlinear dynamic equations. These equations have not worked out yet. Only in exceptional case; however, a large number of the involved parameters were crossed out and an approximation model was presented instead. This issue caused many problems for designing a cement rotary kiln controller. In this thesis, we employed a nonlinear system identification method for identification,...
Entanglement and Decoherence in Optomechanical Systems Coupled through Photothermal Effects
, Ph.D. Dissertation Sharif University of Technology ; Bahrampour, Alireza (Supervisor)
Abstract
Optomechanical systems have attracted considerable attention in the last decade. Such a raising prominence is mainly due to its capability in providing new insight into the quantum behavior of macroscopic objects and exploring the interface between quantum and classical mechanics. Alongside this fundamental quest, cavity optomechanics has many other benefits, ranging from very precise measurements on forces and positions to quantum information processing. In this thesis, we investigate quantum properties of such systems. Particularly, we study cooling of the mechanical resonator toward its ground state and the entanglement between this mechanical resonator and the cavity field. Cooling the...
Improvement in Reinforced Concrete Beam-Column Connections Behaviour using FRP Sheets
, M.Sc. Thesis Sharif University of Technology ; Khaloo, Alireza (Supervisor)
Abstract
Performance of reinforced concrete frames is highly dependent on detailing of the joint connections between its members, such as beams and columns. To have a good structural behavior, joints must show ductile behavior and designed based on the philosophy of strong column-weak beam. In the case of sever lacking ductility, strength or even rigidity of the connections, or having a weak column-strong beam, in the existing structures, there is a need for seismic upgrading of the connection. There are several ways for seismic upgrading of this type of connections.In the last decade Fiber Reinforced Polymer (FRP) widely has been used to strengthening the reinforced concrete (RC) members. Most of...