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    Probabilistic Damage Models for Detailed Risk Analysis of Buildings with Reliability Methods

    , M.Sc. Thesis Sharif University of Technology Aghababaei Shahrestani, Mohammad (Author) ; Mahsuli, Mojtaba (Supervisor)
    Abstract
    A probabilistic approach to modeling the seismic damage incurred by structural and nonstructural components is developed in this study. For this purpose, Bayesian linear regression is employed to characterize the epistemic uncertainty in the model. In this approach, regressors are constructed based on the mechanics of damage. In turn, the probability distributions of the model parameters and the model error are quantified by Bayesian regression using real-life data from laboratory experiments and/or post-earthquake inspections of damaged components. The study presents the stepwise procedure of collecting the observations, quantifying the repair costs, developing model forms, performing model... 

    Detailed seismic risk analysis of buildings using structural reliability methods

    , Article Probabilistic Engineering Mechanics ; Volume 53 , 2018 , Pages 23-38 ; 02668920 (ISSN) Aghababaei, M ; Mahsuli, M ; Sharif University of Technology
    Elsevier Ltd  2018
    Abstract
    This paper presents probabilistic models and methods for detailed seismic risk analysis of structures using structural reliability methods. This approach to risk analysis is an alternative to those that employ the theorem of total probability and conditional probability distributions. Detailed risk analysis entails probabilistic quantification of responses, the ensuing damage of individual structural and nonstructural components, and the resulting economic and social losses. Such an analysis requires a library of probabilistic models for hazards, responses, damage, repair cost, downtime, and casualty with a specific format as presented in this paper. Two analysis options are proposed: one... 

    Component damage models for detailed seismic risk analysis using structural reliability methods

    , Article Structural Safety ; Volume 76 , 2019 , Pages 108-122 ; 01674730 (ISSN) Aghababaei, M ; Mahsuli, M ; Sharif University of Technology
    Elsevier B.V  2019
    Abstract
    A probabilistic approach to modeling the seismic damage incurred by structural and nonstructural components is developed in this study. The resulting models are intended for use in detailed risk analysis of structures through structural reliability methods. The proposed modeling approach employs Bayesian linear regression to characterize the epistemic uncertainty in the model. In this approach, regressors are selected and constructed based on the mechanics of damage. In turn, the probability distributions of the model parameters and the model error are quantified by Bayesian linear regression using real-life data from laboratory experiments and/or post-earthquake inspections of damaged... 

    Component damage models for detailed seismic risk analysis using structural reliability methods

    , Article Structural Safety ; Volume 76 , 2019 , Pages 108-122 ; 01674730 (ISSN) Aghababaei, M ; Mahsuli, M ; Sharif University of Technology
    Elsevier B.V  2019
    Abstract
    A probabilistic approach to modeling the seismic damage incurred by structural and nonstructural components is developed in this study. The resulting models are intended for use in detailed risk analysis of structures through structural reliability methods. The proposed modeling approach employs Bayesian linear regression to characterize the epistemic uncertainty in the model. In this approach, regressors are selected and constructed based on the mechanics of damage. In turn, the probability distributions of the model parameters and the model error are quantified by Bayesian linear regression using real-life data from laboratory experiments and/or post-earthquake inspections of damaged... 

    Investigation of electrochemical parameters on cost-effective Zn/Ni-based electrocatalysts for electrochemical co2reduction reaction to syngas(H2+CO)

    , Article Journal of the Electrochemical Society ; Volume 169, Issue 4 , 2022 ; 00134651 (ISSN) Shahrestani, S ; Beheshti, M ; Kakooei, S ; Sharif University of Technology
    IOP Publishing Ltd  2022
    Abstract
    Electrochemical CO2 reduction reaction (CO2RR) has been studied in 0.1 M of KCl (pH of 6.96), NaHCO3 (pH of 8.3) and K2CO3 (pH of 11.36) cathodic solutions with various counter electrodes including graphite rod, SS316 rod and Pt mesh at different potential ranges on the Znx-Ni1-x bimetallic electrocatalysts. Among the Znx-Ni1-x electrocatalysts, the Zn-Ni electrode with a composition of 65 wt% Zn and 35 wt% Ni and cluster-like microstructure has the best performance for CO2RR by according to minimum coke formation and optimum CO and H2 faradaic efficiencies (CO FE% = 55% and H2 FE% = 45%). The cyclic voltammetry (CV) measurements and gas chromatography (GC) analysis for the CO2RR showed that... 

    Aerodynamic design of a twin-entry radial-inflow turbine impeller: a numerical and experimental investigation

    , Article Green Energy and Technology ; 2018 , Pages 153-170 ; 18653529 (ISSN) Vaezi, S ; Irandoost Shahrestani, M ; Ravosh, F ; Sharif University of Technology
    Springer Verlag  2018
    Abstract
    In this research, aerodynamic design of a twin-entry radial-inflow turbine was done based on the direct method using a developed design code. The Garrett turbocharger was chosen for this purpose. At the first step, the 1D design, based on the impeller efficiency convergence, was performed. In 3D design, which is divided into preliminary and detail design, the profiles of the impeller and blade angle was carried out. Afterward the 3D shape of the blade can be achieved by combining these profiles. There is a good geometrical agreement between designed impeller and the laboratory’s existing impeller in both steps. In order to predict the performance of the turbine, the 1D analysis code was... 

    Antimicrobial wound dressing containing silver sulfadiazine with high biocompatibility: In vitro study

    , Article Artificial Organs ; Volume 40, Issue 8 , 2016 , Pages 765-773 ; 0160564X (ISSN) Mohseni, M ; Shamloo, A ; Aghababaei, Z ; Vossoughi, M ; Moravvej, H ; Sharif University of Technology
    Blackwell Publishing Inc  2016
    Abstract
    Many patients all over the world suffer from acute wounds caused by traumas or burns. In most crucial cases, skin regeneration cannot be promoted spontaneously, and skin grafts are applied as the main treatment. However, this therapy has some drawbacks which motivate researchers to develop wound dressings. In this study, electrospun mats consisting of polycaprolactone (PCL) and polyvinyl alcohol (PVA) incorporated with silver sulfadiazine (SSD) are proposed to be used as antimicrobial wound dressings with the capability of cell seeding. Various amounts of SSD were loaded into PVA nanofibers, and the effects of SSD particles on the morphological characteristics of nanofibers, mechanical... 

    Deepfake Videos Detection through Deep Analysis of Artifacts of Images

    , M.Sc. Thesis Sharif University of Technology Aghababaei Harandi, Ali (Author) ; Ghaemmaghami, Shahrokh (Supervisor) ; Eghlidos, Taraneh (Supervisor)
    Abstract
    DeepFake is a type of forgery that uses deep learning algorithms to make changes to audio and video content that the audience is unable to detect. Nowadays, due to the threats posed by the use of DeepFake to move people's faces in video, researchers' attention has been drawn to designing methods to detect this type of forgery. Detection methods are usually classified into two types. The first case is the extraction of features to detect forgery distortions, for example, the extraction of facial orientations to detect inconsistencies. The second case is the use of deep learning networks for feature extraction and classification, of which the EfficientNet network is an example. Despite the... 

    Efficient electrochemical CO2 conversion by cobalt-based metal organic frameworks modified by bimetallic gold-silver nanostructures

    , Article Catalysis Science and Technology ; Volume 13, Issue 12 , 2023 , Pages 3645-3654 ; 20444753 (ISSN) Beheshti, M ; Saeidi, M ; Adel Rastkhiz, M ; Shahrestani, S ; Zarrabi, A ; Bai, J ; Simchi, A ; Akbarmolaie, S ; Sharif University of Technology
    Royal Society of Chemistry  2023
    Abstract
    The ongoing and rapid growth of atmospheric CO2 levels causes a crucial worldwide concern. Herein, an efficient electrocatalyst has been introduced for electrochemical CO2 reduction reaction (CO2RR) to address the stability issue of ZIF-67. The catalyst consists of gold and silver nanostructures electrodeposited on the surface of a cobalt-based metal-organic framework (Au-Ag@ZIF-67). The uniform distribution of the Au-Ag alloy without any agglomeration on ZIF-67 was confirmed through microscopic observations. After 13.3 h of CO2RR, the specific surface area of Au-Ag@ZIF-67 slightly decreased, whereas that of ZIF-67 declined drastically, indicating excellent structural stability of the Au-Ag... 

    Construction of an Experimental Device for Foaming Agent and an Experimental Study of the Properties of Foaming Agent

    , M.Sc. Thesis Sharif University of Technology Mohammad Karami (Author) ; Bazargan, Mohammad (Supervisor)
    Abstract
    The primary purpose of acidizing operations in the oil and gas industry is to enhance hydrocarbon production. Acidizing has been a common and conventional method for years, especially when production engineers face issues like declining reservoir pressure leading to reduced production rates. Initially, the treatment solution is referred to as matrix acidizing. In acidizing operations, different additives are combined with the acid to control its behavior in the reservoir. These additives may include iron control agents, corrosion inhibitors, friction reducers, and more. Incompatibility among these additives, the acid, and reservoir fluids can lead to severe damage to the reservoir.... 

    Numerical Analysis of An Annular Gas Turbine Combustor

    , M.Sc. Thesis Sharif University of Technology Gandomi, Mohammad Hossein (Author) ; Farshchi, Mohammad (Supervisor)
    Abstract
    The goal of this research is the simulation of the annular combustion chamber of the turbine engine utilized by liquid fuel. The achievement to this goal will lead to create numerical tools for parametric study, analysis and combustion chamber designing.For this reason simple geometry has been considered. This simplicity of geometry causes to facilitate in parametric study and decrease in saving time for modeling and meshing. This combustion chamber is a simplified model of engine CF6. In recent study, the k – ε realizable model has been used for turbulence modeling. For non-adiabatic condition, chemical reaction is dissolved by utilizing probability density function along with laminar... 

    A misbehavior‐tolerant multipath routing protocol for wireless Ad hoc networks [electronic resource]

    , Article International Journal of Research in Wireless Systems (IJRWS) ; Vol. 2, Issue 9, pp. , Sep. 2013 Sedghi, H. (Haniyeh) ; Pakravan, Mohammad Reza ; Aref, Mohammad Reza ; Sharif University of Technology
    Abstract
    Secure routing is a major key to service maintenance in ad hoc networks. Ad hoc nature exposes the network to several types of node misbehavior or attacks. As a result of the resource limitations in such networks nodes may have a tendency to behave selfishly. Selfish behavior can have drastic impacts on network performance. We have proposed a Misbehavior-Tolerant Multipath Routing protocol (MTMR) which detects and punishes all types of misbehavior such as selfish behavior, wormhole, sinkhole and grey-hole attacks. The protocol utilizes a proactive approach to enforce cooperation. In addition, it uses a novel data redirection method to mitigate the impact of node misbehavior on network... 

    Theoretical and Experimental Study to Conversion of AUC to UO2 by Microwave Heating

    , Ph.D. Dissertation Sharif University of Technology Labbaf, Mohammad Hossein (Author) ; Otukesh, Mohammad (Supervisor) ; Ghannadi Maragheh, Mohammad (Co-Advisor) ; Ghasemi, Mohammad Reza (Co-Advisor)

    Estimating Possible Effects of Subsidies in Competition and Development of Fixed Broadband Internet

    , M.Sc. Thesis Sharif University of Technology Mohammadi, Mohammad Ali (Author) ; Vesal, Mohammad (Supervisor) ; Rahmati, Mohammad Hossein (Supervisor)
    Abstract
    In this work, the dynamic competition between firms providing internet services is studied. The framework is Markov equilibrium whereby structural parameters are obtained using two-step estimations, allowing for analyzing the situation in case of subsidies for service upgrade. The results show that such subsidy has little effect on the number of firms while increasing the number of fast firms  

    SAR Imaging Using the TomoSAR Technique to Resolve Multiple Scatterers

    , M.Sc. Thesis Sharif University of Technology Omati, Mohammad Mahdi (Author) ; Bastani, Mohammad Hassan (Supervisor) ; Karbasi, Mohammad (Co-Supervisor)
    Abstract
    During the last few years, the study of urban environment structures is considered as a research field of interest in remote sensing. In satellite observations of the earth's surface, continuous imaging in terms of time and space has caused the remote sensing technique to be proposed as a useful and efficient tool for the analysis of urban areas. Obtaining quantitative spatial information from the urban environment in fields such as determining the height of buildings plays an essential role in urban planning, monitoring damage to buildings, establishing communication bases and digital cities. During the last two decades, the use of Tomosar approach in order to reconstruct the structures of... 

    Joint Optimization of Computation Offloading and Resource Allocation in Mobile Edge Computing Networks

    , M.Sc. Thesis Sharif University of Technology Shokouhi, Mohammad Hossein (Author) ; Pakravan, Mohammad Reza (Supervisor) ; Hadi, Mohammad (Co-Supervisor)
    Abstract
    Mobile edge computing (MEC) is a promising technology that aims to resolve cloud computing’s issues by deploying computation resources at the edge of mobile network and in the proximity of users. The advantages of MEC include reduced latency, energy consumption, and load on access and mobile core networks, to name but a few. Despite all the aforementioned advantages, the mobility of mobile network users causes the traditional MEC architecture to suffer from several issues, such as decreased efficiency and frequent service interruption. One of the methods to manage users’ mobility is virtual machine (VM) migration, where the VM containing the user’s task is migrated to somewhere closer to... 

    Estimating Price Elasticity of Natural Gas Demand in Iran's Residential Sector: A Regression Discontinuity Approach

    , M.Sc. Thesis Sharif University of Technology Makhsousi, Mohammad Hossein (Author) ; Rahmati, Mohammad Hossein (Supervisor) ; Vesal, Mohammad (Supervisor)
    Abstract
    Estimating the price elasticity of gas demand involves complexities depending on the gas market structure and pricing mechanisms in different countries. Distinguishing between supply and demand shocks and block pricing are among the main challenges that can cause endogeneity in elasticity estimates. Iran's domestic gas network, one of the largest and most extensive household gas markets, is divided into five climatic zones based on weather conditions. The pricing steps for these five climates during the five cold months are such that a customer in a warmer climate pays higher prices. Conversely, the pricing steps for the seven warm months are the same for all climates. This policy creates a... 

    Estimate the Effect of Religiosity on Voter Turnout

    , M.Sc. Thesis Sharif University of Technology Jarrahi, Mohammad Mahdi (Author) ; Rahmati, Mohammad Hossein (Supervisor) ; Vesal, Mohammad (Supervisor)
    Abstract
    The correlation between religious adherence and voter turnout is widely studied. However, whether the relation is causal is an open question. We use Household Expenditures and Income Survey (HEIS) data in Iran, which encompasses nine distinct religious expenditures. These expenditures have low correlation with each other and represent different aspects of religious adherence. We use Imamzadeh (some historical holy shrines) as Instruments to estimate the causal effect of religious expenditures on voter turnout. The results reveal that religious expenditures influence both presidential and parliamentary voter turnout, with a notably stronger impact on presidential elections  

    Simulation and Control of an Aromatic Extractive Distillation Column

    , M.Sc. Thesis Sharif University of Technology Karima, Mohammad Mahdi (Author) ; Shahrokhi, Mohammad (Supervisor)
    Abstract
    In this study steady state and dynamic simulation of an NFM extractive distillation unit for seperation of aromatics and non-aromatic components has been carried out. Column output composition obtained with experimental binary coefficients is compared with those obtainded by UNIFAC equation. The results indicate that using UNIFAC for all binrary coefficients results in an unacceptable error in concentration of benzene. If the experimental binary coefficents of benzene with NFM are used and the rest are calculated by UNIFAC equation, the simulation results will be very close to those obtained via experimental binary coefficients. Also it is shown that considering a constant efficiency for all... 

    Investigation of Transport Phenomena in Clarification of Beer by Membrane Using CFD Method

    , M.Sc. Thesis Sharif University of Technology Kazemi, Mohammad Amin (Author) ; Soltanieh, Mohammad (Supervisor)
    Abstract
    During the brewing process, beer alternately goes through different chemical and biochemical reactions and solid–liquid separation stages. The clarification at the final step of brewing is a highly critical stage when it comes to producing a clear and bright beer. Recently, membrane technology has been successfully used in beer clarification, wherein Kieselguhr (diatomaceous earth) filtration is replaced by cross-flow microfiltration. The most important disadvantages of using microfiltration in clarification of beer is the fouling and flux decline during the process. The phenomenology of fouling mechanisms is still undefined and selection of an appropriate technique for flux enhancement in...