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    FPGA-based Fault Injection for Evaluating the Fault Tolerance of Embedded Processors

    , M.Sc. Thesis Sharif University of Technology Mohammadi, Abbas (Author) ; Ejlali, Alireza (Supervisor)
    Abstract
    One the most important issues in most of embedded systems is reliability and fault tolerance.Ensure of correct operation and evaluate reliability and fault tolerance of embedded proces-sors as a critical part of embedded systems, would be necessary. Fault injection is one themostly used methods for evaluating those features. Using FPGA devices is a good alterna-tive for time consuming simulation-based fault injection method because of their speed. But,there are some critical issues in FPGA-based fault injection methods which are controllabil-ity and observability. In addition to need for efficient and applicable observation and controlmechanism to handle fault injection experiments, a... 

    Investigation of Weak Measurement in Quantum Key Distribution

    , M.Sc. Thesis Sharif University of Technology Mohammadi, Shadi (Author) ; Alireza Bahrampour (Supervisor)
    Abstract
    Quantum key distribution is one of the practical quantum information technologies in labo- ratories with existing equipments.In quantum key distribution protocols, the main challenge is the secrecy of key distribution. One of the new methods of quantum channel error esti- mation is the use of weak measurement. In this thesis, after introducing the main quantum key distribution protocols, we introduce weak measurement and sequential weak measure- ment concepts: the weak measurement methods are exployed to obtain the phase difference between two polarizations with high accuratly. It is also used for in line monitoring and error estimation parameters in some quantum key distribution protocols.... 

    Schaefer–Krasnoselskii Fixed Point Theorems Using a Usual Measure of Weak Noncompactness

    , M.Sc. Thesis Sharif University of Technology Mohammadi, Sajjad (Author) ; Ranjbar Motlagh, Alireza (Supervisor)
    Abstract
    In this thesis, we present some extension of Burton and Kirk fixed point theorem for the sum of two nonlinear operators, which one of them is compact and the other one is strict contraction; and we investigate the existence of fixed point where these two operators don’t need to be weakly continuous. Next, we will check the necessity of some conditions, like being strict contraction or compactness, in some specific Banach spaces, such as reflective spaces or Banach spaces equipped with uniformly convex norm.Finally, we analysis the existence of the solution for integral equations in L1 space by using the expressed theorems  

    Experimental Study of the Effect of Divergence Angle on the Efficiency of Conical Nozzle in a Laboratory Solid Rocket Motor

    , M.Sc. Thesis Sharif University of Technology Karimi, Farhad (Author) ; Farahani, Mohammad (Supervisor) ; Mohammadi, Alireza (Co-Supervisor)
    Abstract
    Most propulsion systems use nozzles to increase the velocity of exhaust gas. Therefore, the efficiency of nozzles is important. Losses due to geometry and physical phenomena inside the nozzle define this efficiency. The length and divergence angle of the nozzle, the throat diameter, the Reynolds number, and the specifications and the combinations of fuel have a direct impact on these losses. Solid propellant rockets are widely used and today optimization of rockets is most noticeable. On the other hand, in different phases of design and optimization, empirical experiments are necessary, which are costly in real dimensions. The use of laboratory motors with specific considerations decrease... 

    Conceptual Design of a Solid Propellant Nanolauncher

    , M.Sc. Thesis Sharif University of Technology Ghadiri, Sajjad (Author) ; Farahani, Mohammad (Supervisor) ; Mohammadi, Alireza (Co-Supervisor)
    Abstract
    Nanolaunchers are launch vehicles capable of carring light payloads (under 50 kg) to Low Earth orbit and received much attention in the few past years. Launching the nanosatellites grown about 30 times from 2008 to 2017. Since this category of launch vehicles has fewer developing costs and lower thechnology level, they fit developing space technology in our country. Conversely, the demand of high propellant mass fraction and specific impulse may be a serious difficulty to attain this technology.The only operating nanolauncher in the world is SS-520-5 which belongs to Japan and is a three-stage solid propellant launcher. The goal of this project is also the conceptual design and feasiblity... 

    Experimental Study of Acceleration Effect on Combustion Chamber Pressure Field

    , M.Sc. Thesis Sharif University of Technology Goodarz, Masood (Author) ; Farahani, Mohammad (Supervisor) ; Mohammadi, Alireza (Co-Supervisor)
    Abstract
    This thesis is conducted to study acceleration effect on the burning rate augmentation of a solid propellant. A centrifugal experimental setup is designed to obtain a uniform acceleration field. An internal burning tube is used as grain, so acceleration vector is always perpendicular to burning surface of propellant. Inner radius of tube is small, so the magnitude of acceleration increases as the grain burns back. The pressure of combustion chamber was changed from 30 bar to 80 bar by changing the nozzle throat and the magnitude of acceleration changed from 2g to 60g by changing the rotational speed of SRM. Burning time of all tests was below 2 sec. due to small web of the grain. Pressure of... 

    Photocatalytic Degradation of Pharmaceutical Pollutants using Composites Derived from Layered Double Hydroxides and Metal-Organic Frameworks

    , M.Sc. Thesis Sharif University of Technology Hosseini, Ali (Author) ; Kazemeini, Mohammad (Supervisor) ; Khorasheh, Farhad (Supervisor) ; mohammadi, Alireza (Co-Supervisor)
    Abstract
    The aim of this study is to remove pharmaceutical pollutants through a photocatalytic approach. A layered double hydroxide (LDH) structure was synthesized with the assistance of a metal-organic framework (MOF). Initially, MIL-101(Cr) was synthesized using trivalent chromium ions and subsequently transformed into a layered double hydroxide structure with divalent nickel ions. To further enhance this process, MIL-88(Fe) was prepared using trivalent iron ions, composited with MIL-101(Cr), and then converted into an LDH structure using divalent nickel ions. The resulting photocatalytic composite was fully characterized, and its efficiency in degrading the pharmaceutical compound meropenem was... 

    The Investigation of the Effectiveness of Engine Oil Filter Particle Analysis in Enhancing the Efficiency of Diesel Engine Condition Monitoring Programs

    , M.Sc. Thesis Sharif University of Technology Samaeinejad, Saman (Author) ; Behzad, Mehdi (Supervisor) ; Masoodi, Alireza (Supervisor) ; Mohammadi, Somayeh (Co-Supervisor)
    Abstract
    Over the years, as machines have been invented, their maintenance and repair have consistently been regarded as critical concerns. Oil analysis techniques are an effective method for monitoring the condition of mechanical equipment. Since filters in these devices continually absorb and remove a significant portion of particles from the lubricant, the selection of appropriate filters is crucial. While filters positively affect machine performance, they can also negatively impact oil condition monitoring. To mitigate this negative effect and improve the predictive accuracy of equipment health monitoring, oil filter analysis was conducted. In this research, analytical ferrography tests were... 

    Rcci Curvature for Metric-Measure Space via Optimal Transport

    , M.Sc. Thesis Sharif University of Technology Taheri, Abolfazl (Author) ; 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 (Author) ; 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 (Author) ; 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... 

    3D distributed modeling of trolling-mode AFM during 2D manipulation of a spherical cell

    , Article Journal of Nanoparticle Research ; Volume 23, Issue 4 , 2021 ; 13880764 (ISSN) Mohammadi, S.Z ; Nejat Pishkenari, H ; Mohammadi Moghaddam, M ; Sharif University of Technology
    Springer Science and Business Media B.V  2021
    Abstract
    In this study, a general 3D distributed modeling of Trolling-Mode AFM (TR-AFM) as a nanorobot is presented to analyze the 2D manipulation process of a spherical cell. To this aim, the analysis is categorized into 3 sections. In the first section, 6 deformations of TR-AFM are taken into account, and the standard model of the system is obtained. Moreover, the system is simulated in ANSYS Workbench. The results of modal and transient analyses of the system from both analytical and software methods reveal high agreement, which confirms the accuracy of the presented analytical model. In the second section, by utilizing the 3D derived model, displacement of a spherical yeast single cell (W303)... 

    Sol-gel nanostructured titanium dioxide: Controlling the crystal structure, crystallite size, phase transformation, packing and ordering

    , Article Microporous and Mesoporous Materials ; Volume 112, Issue 1-3 , 2008 , Pages 392-402 ; 13871811 (ISSN) Mohammadi, M. R ; Fray, D. J ; Mohammadi, A ; Sharif University of Technology
    2008
    Abstract
    The anatase phase of titania was stabilised with physically modifying particulate sol-gel process. Two major parameters, peptisation temperature and drying temperature, were identified which were responsible for retarding the anatase to rutile phase transformation, crystal growth and packing of primary particles. The critical nucleus size of transformation was controlled by natural (at 25 °C) and artificial (at 50 and 70 °C) peptisation techniques. Moreover, sintering of primary particles was controlled by cool (at 0 and 5 °C) and normal (at 25 °C) drying techniques. Fourier transform infrared spectroscopy (FT-IR) analysis confirmed that a full conversion of titanium isopropoxide is obtained... 

    , M.Sc. Thesis Sharif University of Technology (Author) ; 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 Safdari, Mohammad (Author) ; 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 Mousavi, Mohammad (Author) ; 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 Khademi, Ali (Author) ; 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 Sadeghian, Masoud (Author) ; 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 Abdi, Mehdi (Author) ; 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 Rokrokian, Ali (Author) ; 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...