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    Bayesian Filtering Approach to Improve Gene Regulatory Networks Inference Using Gene Expression Time Series

    , M.Sc. Thesis Sharif University of Technology Fouladi, Ramouna (Author) ; Fatemizadeh, Emadoddin (Supervisor) ; Arab, Shahriar (Co-Advisor)
    Abstract
    Gene regulatory modeling in different species is one of the main aims of Bioinformatics. Regarding the limitations of the data available and the perspectives which should be taken into account for modeling such networks, proposed methods up to now have not yet been successful in yielding a comprehensive model. In one of the recent researches, the Gene regulation process is considered as a nonlinear dynamic stochastic process and described by state space equations. Afterwards, in order for the unknown parameters to be estimated, Extended Kalman Filtering is used. In this thesis, first of all, Gene complexes are taken into consideration instead of genes and afterwards, Extended Kalman... 

    Protein Function Prediction Using Protein Structure and Computational Methods

    , M.Sc. Thesis Sharif University of Technology Abbasi Dezfouli, Mohammad Ebrahim (Author) ; Fatemizadeh, Emad (Supervisor) ; Arab, Shahriar ($item.subfieldsMap.e)
    Abstract
    Predicting the Amino Acids that have a catalytic effect in the enzymes, is a big step in appointing the activity of the enzymes and classifying them. This is a very challenging job, because an Amino Acid can appear in a variety of active sites.The biological activity of a protein usually depends on the existence of a small number of Amino Acids. Detecting these Amino Acids from the sequence of Amino Acids has many applications. Usually, the Amino Acids that are preserved are known as the Amino Acids that build up the active site, but the algorithms for finding the preserved Amino Acids are much more complex. There are a lot of algorithms for predicting the active sites of Amino Acids, but... 

    Reducing the Flow Rate of Short Circuit Fault Current at the Output of the High Voltage Power Supply

    , M.Sc. Thesis Sharif University of Technology Zibarzani, Ali (Author) ; Kaboli, Shahriar (Supervisor)
    Abstract
    In this research, we have presented a method to delay the propagation of fault current in high voltage power supplies. Common protection methods usually protect the load and do not protect the power supply itself well. In this research, our goal was to propose a method to prevent the short circuit fault current from reaching the power supply elements. At first, the available methods to limit the fault current and protect the high voltage power sources were studied and investigated. Then, using the transmission line theory, a ladder filter was designed as an alternative to the normal filter at the output of the power supply. In the next step, using software simulation, the performance of the... 

    Analysis of a Ultra Narrow Pulse Width High Voltage Generator

    , M.Sc. Thesis Sharif University of Technology Farajzadeh Galeh, Amin (Author) ; Kaboli, Shahriar (Supervisor)
    Abstract
    A Tesla charged PFL Bipolar pulsed power generator has been successfully designed and simulated. The compact Tesla transformer that it employs has successfully charged capacitive loads to peak voltages up to 0.6 MV . The Tesla–driven PFL generator is capable of producing a voltage impulse approaching .3 MV with generating a peak electrical power of up to 1.8 GW for 5 ns when connected to a matched resistive load. Potentially for medical application, a bipolar former has been designed and successfully simulated as an extension to the system and to enable the generation of a sinusoid-like voltage impulse with a peak-to-peak value reaching 600 kV and having a frequency bandwidth beyond 1 GHz.... 

    Design and Implement of Very Low Frequency AC Voltage Source

    , M.Sc. Thesis Sharif University of Technology Fathollahi, Mohammad Mahdi (Author) ; Kaboli, Shahriar (Supervisor)
    Abstract
    With the expansion of the use of electric energy, the importance of sustainable supply of this energy has been revealed. The task of supplying this energy is with power systems, therefore, for a stable supply of electrical energy, it is necessary to continuously monitor the systems. Power systems are composed of various destructible components such as cables. There are various methods and tests for maintaining and monitoring power cables. One of the daily maintenance methods of alternating current cables is called very low frequency testing. The main advantage of this test is the small and portable nature of the test equipment. In this thesis, the design of a very low frequency alternating... 

    Fermionic Approach To The One Dimensional Kondo Necklace Model

    , M.Sc. Thesis Sharif University of Technology Arab, Arian (Author) ; Langari, Abdollah (Supervisor)
    Abstract
    Strongly correlated materials are kind of materials in which novel electric and magnetic properties will appear as a result of strong correlations among their electrons like “heavy fermion materials”. Kondo lattice model is a model to describe heavy fermion materials. If we are merely interested in the magnetic properties of heavy fermions we can replace the Kondo lattice Model with the simpler model called the Kondo-necklace model which consists of the interactions only among the spins of the itinerant (conduction) and localized electrons (magnetic impurities) and also the interactions between the spins of the itinerant electrons. In this thesis we investigate the properties of the one... 

    Experimental Study of Oxygen Reduction Reaction (ORR) on Cu-alloys, Electrocatalysts in Alkaline Solution and Theoretical Investigation of Oxygen Adsorption on Cu-alloys Nano-clusters

    , Ph.D. Dissertation Sharif University of Technology Arab, Ramezan (Author) ; Gobal, Fereydoon (Supervisor)
    Abstract
    In this study, electrochemical oxygen reduction reaction (ORR) was studied on Cu, Pd, Rh, Pd-Cu and Rh-Cu alloys in alkaline solution. Pd-Cu and Rh-Cu alloys were prepared by electrochemical methods. On copper electrode it is found that direct oxygen reduction is accompanied by the electrochemical reductions of copper oxides. Also, mechanism and kinetics of reaction change as the amount of copper oxides increase on the surface. For electrodeposited alloys, it is indicated that the reactivity of Pd-Cu and Rh-Cu alloys toward oxygen reduction is higher than pure Pd and pure Rh. The maximum reactivity among Pd-Cu alloys is related to the sample with 24.5% copper content while the maximum... 

    Cavity Quantum Electro-Dynamics in Ultra-Strong Coupling Regime

    , M.Sc. Thesis Sharif University of Technology Arab, Abbas (Author) ; Khorasani, Sina (Supervisor)
    Abstract
    Cavity Quantum Electro-Dynamics (CQED) in Weak, Strong and Ultra-Strong coupling Regimes are studied. A MATLAB m-file is written which is able to solve any arbitrary CQED configuration. This program demands input data such as number of Quantum Dots, number of energy levels of each Quantum Dot, energies of each energy level of Quantum Dots, Number of cavity modes, eign-frequency of each cavity mode, coupling constant, dipole strength of each allowed transition of Quantum Dots and initial state of system from user and begins to solve the Schrodinger equation for annihilation and atomic ladder operators. In addition, coefficients of each possible ket will be calculated. Since, any approximation... 

    Synthesis and Characterization of Bis[2-(2׳-Hydroxyphenyl)- -oxazolinato]Ni(II) Complex and Investigation of it׳s Catalytic Activity in C-C Coupling Heck Reaction

    , M.Sc. Thesis Sharif University of Technology Arab, Zeynab (Author) ; Bagherzadeh, Mojtaba (Supervisor)
    Abstract
    In this study a new Ni(II)-¬oxazoline complex was synthesized by reaction of Ni(CH3COO)2.4H2O and 2-(2׳-hydroxyphenyl)-2-oxazoline ligand in MeOH solvent. The resulting complex bis[2-(2׳-hydroxyphenyl)-2-oxazolinato]Ni(II), was characterized by different spectroscopic methods. X-ray diffraction showed that this complex is four coordinated with a square planner geometry. The complex was applied as an efficient homogeneous catalyst in C-C coupling Heck reaction of arylhalides with olefins such as methylacrylate. Investigation of the catalytic activity of the complex in Heck reaction between arylhalides and olefins showed high yield and selectivity. For example reaction between iodobenzene and... 

    Formulation and Properties of Scaffolds based on Hydroxyapatite Composites Containing Titanium Dioxide and Magnesium Oxide

    , M.Sc. Thesis Sharif University of Technology Arab, Mehdi (Author) ; Nemati, Ali (Supervisor)
    Abstract
    This study investigates the effect of titanium dioxide and magnesium oxide additives on hydroxyapatite synthesized by sol-gel and composite with the predominant phase of hydroxyapatite by in situ method to improve mechanical properties. Scaffold samples were synthesized with nanometer-sized hydroxyapatite and composite powder particles by gel casting and sintered at 1200 ° C. Then, to evaluate the synthesized powders, simultaneous thermal analysis (STA), X-ray diffraction test, FTIR test, FESEM, EDS, and MAP analysis were used. Also, to evaluate the mechanical properties of the scaffolds, a compressive test was used, and to evaluate the scaffolds' density, the Archimedes method was used.... 

    Optimization of the Capability of Native Microorganisms Isolated from the Landfill of Electronic Wastes in Bioleaching of E-Waste

    , M.Sc. Thesis Sharif University of Technology Arab, Bahareh (Author) ; Yaghmaei, Soheila (Supervisor)
    Abstract
    Given the complex structure of electronic waste and the difficulty of recycling it by traditional methods, the focus is mainly on biohydrometallurgy method, and in particular on bioleaching. To recover metals, various microorganisms are utilized in this method. In light of previous studies, cyanogenic bacteria have been widely used for the extraction of basic and precious metals. Among the species, indigenous microorganisms have a higher ability to resist toxic environments in the bioleaching of metals due to their adaptation by rapid changes in their metabolic system over time. The main objective of this study is to isolate indigenous microorganisms from electronic waste landfill for their... 

    Prediction of Flow Profiles in Different Well Layers using Fiber Optic Data Analysis

    , M.Sc. Thesis Sharif University of Technology Arab, Alireza (Author) ; Bazargan, Mohammad (Supervisor)
    Abstract
    Downhole temperature measurement is one of the key tools for monitoring and analyzing the performance of production wells, evaluating water injection, and identifying multiphase flows within wells. The development of fiber optic technology and tools such as distributed temperature sensors has enabled the recording of high-resolution and detailed temperature profiles. These data, which measure temperature over a wide range along the wellbore, allow researchers to analyze complex downhole processes and identify fluid entry from various reservoir layers. However, accurately distinguishing the contribution of each layer to the total flow rate, especially under multiphase flow conditions and... 

    Climate Change and Mortality: Evidence from Iran

    , M.Sc. Thesis Sharif University of Technology Arab, Pouya (Author) ; Vesal, Mohammad (Supervisor)
    Abstract
    Due to the prominence of the evaluation of the consequences of rising temperatures, this paper examines the effects of temperature variation on mortality across different demographic groups in Iran. I use a rich weekly data set from 2009 to 2017 across different demographic groups to understand the potential health impacts of climate change in a developing country. Using several fixed effect regressions, I discover that for an additional day with a mean temperature over 25°C, mortality rate increases by 2.56% relative to the effects of an extra day in 0-5 °C, in the weekly temperature exposure horizon. I test for the harvesting effect by comparing the estimates at weekly and monthly... 

    Numerical and Experimental Analysis of Biomechanical Behavior in Persian Fixation Method for Distal Humerus Fractures

    , M.Sc. Thesis Sharif University of Technology Hakiminejad, Alireza (Author) ; Nourani, Amir (Supervisor) ; Shahriar Kamrani, Reza (Supervisor)
    Abstract
    Distal humerus fractures commonly take place in adults with low bone mineral density causing major technical challenges upon orthopedic surgeons. Persian fixation method was introduced as a novel technique to stabilize small fragments in comminuted distal humerus fractures using a set of K-wires and reconstruction plate. The objective of the present study is to measure the stiffness and stability of this technique and analyze the effect of influential parameters with numerical simulation and biomechanical testing on a cadaveric specimen. Furthermore, we were able to propose new method to model plastic deformation of implants in surgery.Validation of the finite element (FE) model was... 

    Adsorption and dissociation of hydrogen peroxide on small Pd xM3-x (M = Pt, Cu; X = 1-3) clusters: A hybrid density functional study

    , Article Molecular Physics ; Volume 109, Issue 14 , May , 2011 , Pages 1797-1804 ; 00268976 (ISSN) Nahali, M ; Gobal, F ; Arab, R ; Sharif University of Technology
    2011
    Abstract
    The adsorption and dissociation of H2O2 on small PdxM3-x (M=Pt, Cu; x = 1-3) clusters is investigated using the B3PW91 hybrid density functional method. Natural bond orbitals are analysed to obtain partial charges on atoms, dipole moments, bond orders, and hybrid orbitals of the PdxM3-x-H2O2 systems. The calculated adsorption energies are in the range of -0.32 to -2.12 eV. Generally, H2O2 adsorbs on top positions through one of its oxygen atoms and only in a few cases reacts with the cluster through both oxygen and hydrogen sides. In the latter case the cluster sites which are negatively charged interact with the hydrogen atoms. Interestingly, on the triplet Pd2Pt cluster, H2O2 dissociates... 

    Determination of antioxidant component and activity of rice bran extract

    , Article Scientia Iranica ; Volume 18, Issue 6 , December , 2011 , Pages 1402-1406 ; 10263098 (ISSN) Arab, F ; Alemzadeh, I ; Maghsoudi, V ; Sharif University of Technology
    2011
    Abstract
    Rice bran is one of the most important co-products in the rice milling. In this research, antioxidant activity of two Iranian rice bran varieties, Fajr and Tarem, extracted by three different solvents (methanol, ethanol and ethyl acetate) was evaluated. The order of antioxidant activity was evaluated by measurement of total phenolic content, antioxidant activity in linoleic acid system, reducing power and scavenging capacity by DPPH radical. The methanolic extract of Fajr rice bran showed a total phenolic content of 3.31 mg Gallic acid/gr rice bran and a DPPH free radical-scavenging activity of 93.91%, achieved at 50 mg/ml concentration, and a percent inhibition of linoleic acid peroxidation... 

    DFT study of nitrogen monoxide adsorption and dissociation on Rh[sbnd]Cu nano clusters

    , Article Journal of Alloys and Compounds ; Volume 695 , 2017 , Pages 1924-1929 ; 09258388 (ISSN) Arab, A ; Nahali, M ; Gobal, F ; Sharif University of Technology
    2017
    Abstract
    Adsorption and dissociation of NO on RhxCu4-x(x = 0–4) nano clusters were investigated using density functional theory. Adsorption energy, total charge on NO, NO bond length, and NO vibrational frequency for various modes of NO adsorption were analyzed. Adsorption from the nitrogen end of NO on the Rh atom(s) of the clusters are more favored and adsorption energies are in the −1.02 eV to −2.59 eV range. NO binds stronger to Rh-Cu mixed clusters compared to pure Cu4 cluster, so N[sbnd]O bond is significantly weakened upon adsorption on the former. NO binding to more atoms of the clusters results in a corresponding decrease of the N[sbnd]O vibrational frequency. Dissociation of NO was also... 

    Effect of Equal Channel Angular Pressing(ECAP) Parameters on Microstructure and Mechanical Properties of Strip Samples of AZ31 Mg Alloy

    , M.Sc. Thesis Sharif University of Technology Arab, Mohammad (Author) ; Akbarzadeh Changiz, Abbas (Supervisor)
    Abstract
    Equal Channel angular pressing (ECAP) is one of the most applicable Severe Plastic Deformation (SPD) Procedures which results in improvement of strength and ductility through grain refinement and an appropriate texture development. In this study, in order to achieve a proper orientation and microstructure, ECAP was performed in different routes and temperatures up to 4 passes on AZ31 magnesium alloy. Microstructure and mechanical properties were studied. X-ray diffraction analysis was performed to study the basal orientation variation and calculation of sub-grain size. In addition, cold rolling at room temperature was done on the fourth pass specimens, in order to study the effect of ECAP... 

    A Hybrid Simulated Annealing Algorithm For Winner Determination problem In Combinatorial Auction

    , M.Sc. Thesis Sharif University of Technology Arab Momeni, Mojtaba (Author) ; Kianfar, Farhad (Supervisor)
    Abstract
    One of the most important issues that an organization faced with is resource management. The proper resource management has the great rule in organization cost reduction. One of the most efficient processes in resource allocation is auction and there is different auction with different mechanism and goals. In an auction there is a set of items and a set of bids, and the task of auctioneer is matching items with suitable bids. Each bid consist of desirable items and the bidder value of that items. In an auction process, after mechanism design of auction and auction implementation we must identify the winners of auction and this is a hard problem even in simple auction.
    In this study we... 

    A No-Wait Flowshop Scheduling Problem with Sequence Dependent Setup Time

    , M.Sc. Thesis Sharif University of Technology Arab Ameri, Sedighe (Author) ; Salmasi, Nasser (Supervisor)
    Abstract
    In this research a no-wait flowshop sequence dependent setup time scheduling problem with weighted earliness-tardiness penalties as the criterion (F_m |nwt,S_ijk |∑▒〖w_j^' E_j+w_j^" T_j 〗) is investigated. It is assumed that n jobs are assigned to a flowshop with m machines. The jobs are not allowed to wait between two successive machines according to no-wait requirement. Moreover each machine needs a setup time before processing a new job. The value of this setup time is dependent on the previous processed job on that machine.
    A mixed integer linear programming model is proposed to solve the problem. As the problem is shown to be strongly NP-hard, a particle swarm optimization (PSO)...