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ayatizadeh-tanha--maryam
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Total 94 records
Reaction Modeling of Mercaptan Conversion to H2S and Hydrocarbons over ZSM-5 Catalysts in Microreactor
, M.Sc. Thesis Sharif University of Technology ; Kazemeini, Mohammad (Supervisor)
Abstract
Microfluidic devices carry fluids in channels with the diameter in the scale of micrometers. Low consumption of raw materials, higher selectivity, enhancement of heat and mass transfer, and improved safety considerations are benefits of the application of microfluidic devices. In this venue, catalytic microreactors get high potential in the filed of the catalytic reaction. In recent years due to strict international environmental regulations, the sulfur content in fossil fuels should be at the minimum content. MEROX process is to most common route to remove mercaptan from the LPG dreams in the material gas refineries. However, in this process, the production of DiSulfid Oil (DSO) is a...
The Application of Fuzzy Customer Clustering Results in Distribution Fleet Assignment to Customer Demands Considering Sales and Distribution Simultaneously
, M.Sc. Thesis Sharif University of Technology ; Haji, Alireza (Supervisor)Airport Capacity Determination by Fuzzy Logic
, M.Sc. Thesis Sharif University of Technology ; Malaek, Mohammad Bagher (Supervisor)
Abstract
An automatic air traffic controller system is designed in this research. The major goal is to aid the human controller in decision making at real air traffic control situations. The air traffic system is modeled by queuing theory. Since respond rapidity is very important in air traffic control, so the fuzzy logic is utilized to construct a rule-base. This rule-base determines optimum policies while considering the operational matters, minimum separation distance requirements, air traffic controller techniques, and work-load. This project is an initial design for air traffic automation system which considers scheduling optimality as well as delay reduction. The case study is done on Denver...
3d Design of a Microfluidic Chip for Anticancer Drugs Screening
, M.Sc. Thesis Sharif University of Technology ; Mashayekhan, Shohreh (Supervisor) ; Saadatmand, Maryam (Supervisor)
Abstract
Nowadays, advanced and inexpensive pre-clinical methods for investigating the effects of anti-cancer drugs are expanding. One of the latest three-dimensional laboratory modeling for evaluating the effects of drugs is the use of tumor-on-chip technology, which actually models the physiological system of the body through three-dimensional scaffolds, multicellular cultures, and shaped vascular systems. In this study, three-dimensional culture of cancer cells was performed in the form of spheroids. A chip of U-shaped microstructures with and without gaps was used to trap cells and form cancer spheroids. We simulated the simultaneous effect of drug and oxygen concentration distribution inside the...
Providing a Model for Formulation of Technological Strategy in the Field of Hybrid & Electric Vehicles in Iran Khodro Car Maker Company
, M.Sc. Thesis Sharif University of Technology ; Arasti, Mohammad Reza (Supervisor)
Abstract
Companies are facing increasingly faster pace of technological evolution. Running a business with a large supply chain without considering the technological changes in the environment might provoke a difficult situation and result in competitive disadvantage. The field of hybrid and electric vehicles has developed a lot in the last decade in the world and the technologies of this field are developing in a dynamic circumstance. Iran Khodro, as the largest automaker in Iran, cannot be indifferent to this reality. Despite the huge oil and gas resources in the country, is it necessary to develop hybrid and electric vehicles in Iran? This is the main question we are trying to answer in the first...
Numerical simulation of vortex-induced vibration of a smooth circular cylinder at the subcritical regime
, Article Proceedings of the Institution of Mechanical Engineers Part M: Journal of Engineering for the Maritime Environment ; Volume 236, Issue 4 , 2022 , Pages 916-937 ; 14750902 (ISSN) ; Nemati Kourabbasloo, N ; Mohtat, P ; Tanha, A ; Sharif University of Technology
SAGE Publications Ltd
2022
Abstract
The present paper focuses on the simulation of vortex-induced vibration (VIV) of a rigid, smooth circular cylinder with elastic supports subject to a cross-flow at the subcritical regime of Reynolds number, 30,000
Model Checking of Stochastic Activity Networks
, M.Sc. Thesis Sharif University of Technology ; Movaghar, Ali (Supervisor)
Abstract
Modeling and performance evaluation of the real time distributed systems is a significant problem. Stochastic activity network is one of the high level models used for this purpose. This network is an extension of generalized stochastic Petri net which is more powerful and flexible than other Petri net extensions. Checking the satisfiability of properties such as performance, dependability and user's expected properties is considerable in these models. Thus, using the approaches and generating modeling and model checking tools with the mentioned purpose is attractive. A model checker automatically checks the correctness of the system behaviors as properties against the model by getting the...
Fabrication of Thick Scaffold with Microfluidic Channels by Bioprinter
, M.Sc. Thesis Sharif University of Technology ; Saadatmand, Maryam (Supervisor)
Abstract
Cardiovascular diseases are among the leading causes of death worldwide. For instance, in 2015, almost 31% of the world’s mortality rate was due to these causes. One of these diseases is cardiac coronary vessels’ occlusion which leads to the insufficient blood supply to the heart tissue and cardiomyocytes death after Myocardial Infarction (MI). After MI, a hierarchy of events in the heart tissue changes heart muscle and forms cardiac fibrosis. This fibrotic tissue does not have the native one’s properties and function, so it will cause cardiac arrest and patient death. Therefore, it is obvious that vascular network plays a crucial role in the heart function. The importance of cardiac...
Robust Estimation and Control of a Planet Lander
, M.Sc. Thesis Sharif University of Technology ; Kiani, Maryam (Supervisor)
Abstract
This study has focused on the important problem of landing on a planet as an important current and future space mission. In this regard, dynamics modeling and integrated state estimation and control problems have been investigated in different views. To this aim, first a novel concurrent representation for translational and rotational kinematics has been developed based on the extension of modified Rodrigues parameters to dual space. This parameter set, called dual modified Rodrigues parameters (DMRP), is then utilized to establish an integrated roto-translational dynamic. The proposed DMRP-based kinematics and dynamics have been verified via comparison to traditional methods of...
Optimal Control of Unknown Interconnected Systems via Distributed Learning
, M.Sc. Thesis Sharif University of Technology ; Babazadeh, Maryam (Supervisor)
Abstract
This thesis addresses the problem of optimal distributed control of unknown interconnected systems. In order to deal with this problem, a data-driven learning framework for finding the optimal centralized and the suboptimal distributed controllers has been developed via convex optimization.First of all, the linear quadratic regulation (LQR) problem is formulated into a nonconvex optimization problem. Using Lagrangian duality theories, a semidefinite program is then developed that requires information about the system dynamics. It is shown that the optimal solution to this problem is independent of the initial conditions and represents the Q-function, an important concept in reinforcement...
Utilizing Gaussian Processes to Learn Dynamics of Unknown Torques Acting on a Spacecraft
, M.Sc. Thesis Sharif University of Technology ; Kiani, Maryam (Supervisor)
Abstract
Accurate and fast attitude estimation of a rigid body plays an essential role in the performance of a vehicle’s control system, especially aerospace vehicles. Ample works have been done to increase the accuracy and speed of the attitude estimation process, but all have been developed according to a model-based approach. This approach assumes that the torques acting on the body have a known dynamical model that is used for the attitude estimation. The purpose of the present research is to estimate the attitude via a model-free approach, i. e. dynamics of the torques acting on the body are no longer assumed to be known, and its learning is the next step. Thus, the problem formulation of this...
Stabilization and Pole-Placement by Structurally-Constrained Controllers: A Graph-Theoretic Approach
, M.Sc. Thesis Sharif University of Technology ; Babazadeh, Maryam (Supervisor)
Abstract
This thesis presents a new approach to design structural output feedback controllers with stabilization and pole-placement at desired points on the S plane. It is assumed that the linear time-invariant system has no fixed mode corresponding to the specified control structure, outside the desired region of the closed-loop poles, such that the structural controller design problem is theoretically feasible. To this end, the structural output controller design problem is first transformed into a structurally equivalent problem based on the solution of a set of discrete linear programs. Then, by using the resultant structure, a new method is proposed for designing static and dynamic control loops...
Fabrication the Hydrogel Microfibers Using Bioprinter with Application in Cardiovascular Model
, M.Sc. Thesis Sharif University of Technology ; Saadatmand, Maryam (Supervisor)
Abstract
Cardiovascular disease (CVD) currently remains a considerable challenge for clinical treatments. CVDs account for N17.5 million deaths per year and will predictably increase to 23.6 million by 2030. The main purpose is to create human model systems to study the effect of disease mutations or drug treatment on the heart. In addition, engineered cardiac tissues are considered promising candidates to be transplanted to improve the function of diseased hearts. For engineered active tissues/organs, 3D bioprinting can fabricate complex tissue architecture with a spatiotemporal distribution of bioactive substances (cells, growth factors, and others) to better guide tissue regeneration. However,...
Design of Microfluidic Chip for 3D Cell Culture
, M.Sc. Thesis Sharif University of Technology ; Saadatmand, Maryam (Supervisor)
Abstract
Understanding biological systems requires extensive knowledge of individual parameters, and to study the processes of cell differentiation and cell behavior, a suitable environment must be created with the physiological conditions of the human body. For this purpose, with the knowledge of microfluidics, a microenvironment can be provided to study the behavior of cells on a small scale. The use of bone tissue model microfluidic chips is an alternative and new method in which it is possible to study the behavior of cells to differentiate into bone and to examine the toxicity of drugs, which in itself can help in the effective and successful treatment of these cases show. Therefore, in this...
Optimal Energy Trading in a Smart Grid Based on Extremum-seeking Algorithm
, M.Sc. Thesis Sharif University of Technology ; Babazadeh, Maryam (Supervisor)
Abstract
Prevalent deployment of Distributed Energy Resources(DERs) in the demand side of electrical energy grids has several advantages such as greenhouse gases emission reduction, mitigation of power losses in the distribution grids and abatement of the dependency on the wholesale generation companies. At the same time, it paves the way for the advent of local interactive energy trading frameworks. In the following thesis, a distributed data-driven algorithm is developed for market-clearing in a community-based local energy market. The social welfare maximization is considered as the objective of the energy trading. The production and demand of electricity are the decision variables of sellers and...
Navigation and Control of a Free-Flying Satellite for Cargo Transportation and Placement in Intra-Vehicular Environment
, M.Sc. Thesis Sharif University of Technology ; Kiani, Maryam (Supervisor)
Abstract
The main topic of this research is the navigation and control of a free-flying satellite with a robot manipulator while transferring and placing cargo on a space station. After connecting the cargo module, astronauts and robots need to deliver the available loads to the desired modules in a space station. Capturing an object or cargo is a critical issue studied extensively so far. However, delivery and placing of the cargo at the target point have not been investigated yet, to the best of the author’s knowledge; hence, this is a primary motivation for conducting the proposed research. After capturing the payload, the position and attitude of the manipulator with respect to the station’s...
Fixed-Time Consensus Control of Unknown Multi-Agent Systems Based on Distributed Reinforcement Learning
, M.Sc. Thesis Sharif University of Technology ; Babazadeh, Maryam (Supervisor)
Abstract
This thesis introduces a distributed backstepping control strategy based on reinforcement learning to achieve fixed-time consensus in high-order nonlinear multi-agent systems. Each agent, whether a leader or a follower, is modeled using a strict feedback approach, incorporating uncertainties as unknown nonlinear functions and disturbance signals across all state variables. The communication network among agents can be either directed or undirected, with a fixed topology. Each follower employs a control law derived from actor-critic networks, utilizing only the outputs from neighboring agents. The proposed method combines virtual and actual backstepping control laws, formulated from two key...
Employing humanoid robots for teaching english language in Iranian junior high-schools [electronic resource]
, Article International Journal of Humanoid Robotics ; Vol. 11, No. 3 (2014) 1450022 ; Meghdari, Ali ; Ghazisaedy, Maryam ; Sharif University of Technology
Abstract
This paper presents the effect of robotics assisted language learning (RALL) on the vocabulary learning and retention of Iranian English as foreign language (EFL) junior high school students in Tehran, Iran. After taking a vocabulary pre-test, 46 beginner level female students at the age of 12, studying in their first year of junior-high participated in two groups of RALL (30 students) and non-RALL (16 students) in this study. The textbook used was the English book (Prospect-1) devised by the Iranian Ministry of Education for 7th graders, and the vocabulary taught and tested (pre-test and post-test) were taken from this book. Moreover, the treatment given by a teacher accompanied by a...
An Approximation Method for Reliability Analysis of Standby Systems
, M.Sc. Thesis Sharif University of Technology ; Eshraghniaye Jahromi, Abdolhamid (Supervisor)
Abstract
Analyzing reliability of large cold-standby systems has been a complicated and time-consuming task, especially for systems with components having non-exponential time-to-failure distributions. In this research, an approximation model, which is based on the central limit theorem, is presented for the reliability analysis of binary cold-standby systems whit non-identical components. The proposed model can estimate the reliability of large cold-standby systems with binary-state components having arbitrary time-to-failure distributions in an efficient and easy way. The accuracy and efficiency of the proposed method are illustrated using several different types of distributions, such as...
Implementation of absolute quantification in small-animal SPECT imaging: Phantom and animal studies
, Article Journal of Applied Clinical Medical Physics ; Volume 18, Issue 4 , 2017 , Pages 215-223 ; 15269914 (ISSN) ; Vosoughi, N ; Tanha, K ; Assadi, M ; Ghafarian, P ; Rahmim, A ; Ay, M. R
John Wiley and Sons Ltd
2017
Abstract
Purpose: Presence of photon attenuation severely challenges quantitative accuracy in single-photon emission computed tomography (SPECT) imaging. Subsequently, various attenuation correction methods have been developed to compensate for this degradation. The present study aims to implement an attenuation correction method and then to evaluate quantification accuracy of attenuation correction in small-animal SPECT imaging. Methods: Images were reconstructed using an iterative reconstruction method based on the maximum-likelihood expectation maximization (MLEM) algorithm including resolution recovery. This was implemented in our designed dedicated small-animal SPECT (HiReSPECT) system. For...