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    Design and Simulation of a Dedicated Analog Circuit to Protect against Power Analysis Attack

    , M.Sc. Thesis Sharif University of Technology Khoeini, Farzad (Author) ; Sharifkhani, Mohammad (Supervisor)
    Abstract
    With the rapid development of the communication technology, the demand for secure data transferring is inevitable. In this regard, all of secure systems such as Sim-Cards, Smart Cards, to name but a few, enjoy crypto hardware in order to encrypt data. The palpitating heart of these apparatuses, that is, processor, is based on well-known cryptographic algorithms such as AES, RSA, etc. In short, the security depends on the hidden key and in e. g., AES-128 bit, time to disclose the key is in order of 2128. Therefore, no computer can disclosure it in that this period is approximately equivalent to 1032 years in case of the processing computer runs on a 1GHz clock frequency, and a try-out of a... 

    Damage Detection and Evaluation of Repair Materials and Techniques for Concrete Bridges

    , M.Sc. Thesis Sharif University of Technology Karimi, Roya (Author) ; Joghataie, Abdoreza (Supervisor)
    Abstract
    Poor maintenance of concrete bridges in the past years in Iran, caused serious damages, so most of them need rehabilitation. The majority of repaired members are exposed to repeated damage because compatibility of repair material to substrate concrete not considered as well as weather and loading conditions. This study attempts to improve the repair achievement and durability of concrete bridges. This investigation contains two phases: preliminary study and experimental phase. Preliminary study attends to detect different types of damages of concrete bridges and their causes along with their propagation. The next part of this study discusses about various types of repair materials. In... 

    Parametric Study of Concrete Connection Retrofitted by Steel Jacketing

    , M.Sc. Thesis Sharif University of Technology Makiabadi, Reza (Author) ; Mofid, Massoud (Supervisor)
    Abstract
    This study investigates the cyclic experimental behavior of damaged exterior reinforced concrete beam–column joint specimens retrofitted with the proposed technique using steel elements called steel prop and curb. The technique is usable for local and global strengthening of reinforced concrete frames. Four half-scale RC joints were tested under the cyclic loading; two control specimens with the different beam heights were loaded up to their ultimate strength and this was followed by retrofitting of these damaged specimens as new specimens and tested again under the same loading system. This study indicate the importance of some parameters such as friction , jacket place , thickness of plate... 

    On the investment in a reliability improvement program for warranted second-hand items

    , Article IIE Transactions (Institute of Industrial Engineers) ; Volume 43, Issue 7 , Mar , 2011 , Pages 525-534 ; 0740817X (ISSN) Shafiee, M ; Chukova, S ; Yun, W. Y ; Niaki, S. T. A ; Sharif University of Technology
    2011
    Abstract
    A reliability improvement program (such as an upgrade action) can be seen as an investment by a dealer to restore a second-hand product to a better operational state. Due to the nature of the actions performed, the item's reliability at the end of this program is usually uncertain. This article develops a stochastic cost-benefit model for investment made in reliability improvement programs for second-hand items sold with failure-free warranty. Depending on the product's lifetime modeling approach, two modifications of the model are considered and are solved for the optimal improvement level. A real case application of the model is presented to validate the proposed approach  

    On the Characteristics and Performance of RCFrames with Y-Bracing Systems

    , M.Sc. Thesis Sharif University of Technology Atri, Saman (Author) ; Mofid, Masood (Supervisor)
    Abstract
    Steel bracing systems can be used effectively for seismic retrofitting of existing RC buildings as well as for seismic design of new building. Steel bracing system has been used to increase the lateral load resistance of steel structures. In recent years the concept of steel bracing has also been applied to the retrofitting of reinforced concrete frames, especially to improve seismic performance of non-ductile reinforced concrete buildings. The use of steel bracing systems for seismic rehabilitation of RC frames offers some advantages such as (a) minimal added weight to the structure; (b) ease and speed of construction;(c) increased architectural flexibility; in comparison with RC shear... 

    Modeling of in Plane Behavior of Retrofitted Adobe Walls with Finite Element Method under Cyclic Loading

    , M.Sc. Thesis Sharif University of Technology Mohammad Panah, Hossein (Author) ; Bakhshi, Ali (Supervisor) ; Ghannad, Mohammad Ali (Co-Advisor)
    Abstract
    Statistical studies indicate the fact that in Iran, like many other developing countries, a significant percentage of buildings are made of traditional materials and most of them are adobe buildings especially in rural areas. Furthermore, geological data indicates that Iran is located in alps-Himalayas seismic zone and exposed by destructive earthquakes and adobe buildings suffer the most damages comparing with other type of the structures. According to these explanations, this research deals with adobe buildings behavior and provides solutions for reinforcing them and improving the seismic response of these buildings. These studies include numerical modeling with finite elements methods by... 

    Performance of RC Shear Walls Strengthened by Vertical Strips of Steel Plates under Seismic Loading

    , M.Sc. Thesis Sharif University of Technology VatanKhah Rahmani, Borna (Author) ; Khaloo, Alireza (Supervisor)
    Abstract
    Even though a considerable amount of research has been conducted on composite wall system during past years, very limited research has been reported on shear walls strengthened by steel plates. In 2008, the composite shear wall, which consisted of reinforced concrete wall, retrofitted by steel plates, attached to both sides of RC walls using mechanical connectors in form of shear studs, bolts or lateral ties tested under axial load and lateral force. In this research, seismic behavior of RC shear walls strengthened by vertical strips of steel plates is going to be studied. The result will be compared with RC shear wall which fully covered by steel plates. The behavior of RC shear wall will... 

    Performance of RC Shear Walls Strengthened by Diagonal Strips of Steel Plates under Seismic Loading

    , M.Sc. Thesis Sharif University of Technology Fayyazi, Davood (Author) ; khalo, Alireza (Supervisor)
    Abstract
    Even though a considerable amount of research has been conducted on composite wall system during past years, very limited research has been reported on shear walls strengthened by steel plates. In 2008, the composite shear wall, which consisted of reinforced concrete wall, retrofitted by steel plates, attached to both sides of RC walls using mechanical connectors in form of shear studs, bolts or lateral ties tested under axial load and lateral force. In this research, seismic behavior of RC shear walls strengthened by diagonal strips of steel plates is going to be studied. The result will be compared with RC shear wall which fully covered by steel plates.The behavior of RC shear wall will be... 

    Strategic Studies on Bioproducts Supply at the Present Situation of Local and Global Markets

    , M.Sc. Thesis Sharif University of Technology Hosseini, Hamid Reza (Author) ; Roostaazad, Reza (Supervisor) ; Maleki, Ali (Co-Advisor)
    Abstract
    in the present situation most of the bioproducts are supplied at the global markets. hence newcomers and also existing suppliers should study the economic and social trends to make strategic decisions in order to enter new markets. analysis of the effect of different parameters on the market entrance strategy is the main focus of this thesis. the pivotal subject of this thesis is the analysis of Enzyme industry value chain in Iran and the role of each actor and their interactions with each other. after visualizing the Enzyme industry value chain, we want to answer this question: what are the main obstacles for entering the Enzyme industry due to the interactions between the industry... 

    Adsorption and Conversion of Heavy Oil Asphaltene on Composite Nanostructures

    , M.Sc. Thesis Sharif University of Technology Torka Bidokhti, Mostafa (Author) ; Ghotbi, Siros (Supervisor) ; Khodadadi, Abbasali (Supervisor)
    Abstract
    The aim of this project was to upgrade and reduce viscosity of heavy oils by adsorbing of asphaltene on Ni-Mo/CB and converting it into lighter and more valuable gas and liquid compounds. Asphaltene has been extracted from a heavy crude oil sample of Soroush oil field in Iran. After adsorption, Asphaltene conversion to lighter components (gas/liquid) was studied through hydrocracking process. To prepare the support of catalyst, Carbon Black, initially a thermal treatment step under the argon gas atmosphere followed by acid-washing process was performed. Afterward, the catalysts was prepared through dry impregnation method. In order to activate catalyst for hydrocracking, the catalysts has... 

    Upgrade Feasibility Studyof a Class D Gas Turbine

    , M.Sc. Thesis Sharif University of Technology Shariat, Mohammad (Author) ; Ghorbanian, Kaveh (Supervisor)
    Abstract
    The purpose of this thesis is to investigate and identify the performance of a class D gas turbine and improve its efficiency.This thesis contains three parts: first part is to choose a specific engine in class D, for our case “Centaur 40”, then this engine, model and validate by GASTURB with existed data.Second part is tosurvey methods of pgradedemonstrated gas turbine with regard to upgraded Solar Centaur 40 “Taurus 60” using the FORTRAN code base on Stage Stacking method.Finally,the last part of this thesis is to investigate Compressor-Turbine matching. In this part the matching zone of the original and upgraded gas turbines are determined and effect of upgrading on matching zone is... 

    Experimental Study of Bond in Curved FRP-Strengthed Beams

    , M.Sc. Thesis Sharif University of Technology Afshari, Majid (Author) ; Vafai, Abolhassan (Supervisor)
    Abstract
    Through the recent years application of FRP material in structural engineering has been developed significantly. According to possible changes of a building function during its lifetime or alteration of the building codes, building structures usually need to be strengthened. Referring to merits of FRP material, its application seems to be a convenient idea toward the cited requirement. Curved beam and slab are known as highly used elements in building structures. Bridges composed of horizontal or vertical arches could be noted as common examples which need to be reinforced by FRP. However curved concrete surfaces, reinforced by FRP plates, seem to be studied than it is really required; For,... 

    Compressive Behavior of Confined Concrete Column with FRP Layers

    , M.Sc. Thesis Sharif University of Technology Mohammadian, Armita (Author) ; Khaloo, Alireza (Supervisor)
    Abstract
    In recent years, the use of fiber reinforced polymer (FRP) jackets, as an external lateral confinement has found considerable attention in retrofitting and strengthening existing reinforced concrete (RC) columns in earthquake prone areas. The FRP composites have numerous advantages such as ease in application, high strength and stiffness-weight ratio, no corrosion and negligible changes in the member dimension. Most of previous studies have concentrated on evaluation of the effect of confinement with spiral bars or FRP composites, separately. However, in practice both types of confinements exist in strengthening RC columns.
    This paper presents the results of a computational modeling to... 

    Numerical Analyses for Flexural Behavior of Bridge Deck Strengthened with Frp Sheets Using Partially Bonding System

    , M.Sc. Thesis Sharif University of Technology Kangani, Ashkan (Author) ; Vafai, Abolhassan (Supervisor)
    Abstract
    During times, reinforced concrete sturctures might need to be strengthened due to environmental factors, material properties, design errors or changes indesign guidelines.Fibre-reinforced-polymer (FRP)composites are prominentmaterialsfor this purpose. Externally full bonding systemhas been widely used for flexural strengthening of reinforced concrete sturctures with FRP. However, the drawback of using this strengthening system is the high reduction of structure's deformability.In this research, partially bonding system used in finite element modeling of a bridge’s deck to increase deformability compared to full bonding system. Results showed that not only deformability but also load... 

    Effect of Corner Radius on Axially-Loaded Square RC Columns Confined with FRP Laminates

    , M.Sc. Thesis Sharif University of Technology Mohammadi Samani, Ali (Author) ; Mostofinejad, Davoud (Supervisor)
    Abstract
    FRP confinement studies on concrete square columns and its effect on design and retrofitting has been the topic of numerous studies in recent years and due to wide spread usage of FRP in structural retrofitting, these studies are still carried out by researchers. One of the most common and accurate methods for predicting the behavior of structures is modeling by Finite Elements Method (FEM). This study aims to assess the effects of corner radius on axially loaded reinforced FRP-confined concrete columns and their behavior for different corner radiuses using FEM software. Using the capability of FEM in ABAQUS software (V 6.8-1), the behavior of square reinforced concrete (RC) columns... 

    Numerical Study on Behavior of RC Shear Wall Retrofitted with FRP Sheets

    , M.Sc. Thesis Sharif University of Technology Shadan, Fariba (Author) ; Khalu, Alireza (Supervisor)
    Abstract
    Shear wall has been widely used in RC structures due to high initial stiffness and lateral load capacity. Hence, the behavior and effectiveness of retrofitting technique on shear wall are needed to be investigated widely. Among several available techniques for retrofitting RC structures, fiber reinforced polymer (FRP) is quite effective because of its high strength-weight ratio, high resistance to corrosion and easy handling and installation. Several researchers have investigated on the behavior of retrofitted RC members with FRP jackets like columns. However, application of FRP laminates on RC walls has attracted less attention by researchers. In this study a numerical investigation on... 

    Rehabilitation of Reinforced Concrete Coupling Beams With FRP

    , M.Sc. Thesis Sharif University of Technology Mirmontazeri, Kaveh (Author) ; Mostofinejad, Davood (Supervisor)
    Abstract
    Shear walls are commonly used in tall concrete buildings to resist lateral loads. Due to the presence of regular door or window openings, a shear wall is often divided into smaller wall units coupled together by coupling beams. In any case, the earthquake resistance of a coupled shear wall structure is highly dependent on the nonlinear behaviour, especially the strength and ductility, of the coupling beams. Many existing building structures without provisions for resisting earthquake loads might no longer be considered to be up to the new standard due to increased-load specifications in the seismic code. A large number of RC coupling beams might require rehabilitation or retrofitting to... 

    Upgrading "Qaed Basir"Petrochemical Wastewater Treatment Plant

    , M.Sc. Thesis Sharif University of Technology Maqsudi, Matin (Author) ; Borghei, Mehdi (Supervisor) ; Shayegan Salek, Jalaledin (Supervisor)
    Abstract
    Golpayegan Qaed Basir Petrochemical Company is one of the lucrative and entrepreneurial companies in Iran. Every day in this complex, a large amount of wastewater is being generated and transferred to the evaporative lag after the primary and secondary purification outside the complex and it is not restored. Considering the growing importance of surface and underground water resources, reuse of wastewater is a valuable production. In this research, the optimization of the sewage treatment system of the complex was evaluated by replacing the chemicals in the primary purification unit and also by using chloride-ferric and trickling filter for tertiary purification(treating) of the... 

    A Power Analysis Countermeasure for a Lightweight Symetric Block Cipher

    , M.Sc. Thesis Sharif University of Technology Safaei Pour, Morteza (Author) ; Salmasizadeh, Mahmoud (Supervisor) ; Moradi, Amir (Co-Advisor)
    Abstract
    Among cryptography devices, resource constrained devices like sensors, RFID tags, smart cards and etc need a special class of cryptography algorithms. These devices have three limitations: memory, consumed power and computing power. Therefore, need a special class of cryptography algorithms that is lightweight cryptography. Lightweight cryptography systems have features and limitations that make them more vulnerable against attacks such as power analysis attacks. For this reason strengthening them against these attacks need more attention. So far, various countermeasure for secure implementation of different cryptography systems proposed. Most of them trying to decrease the correlation... 

    Design of a Fault Tolerant SPARC Based Micro Processor On FPGA

    , M.Sc. Thesis Sharif University of Technology Hosseini, Morteza (Author) ; Rashidian, Bijan (Supervisor) ; Vosoughi Vahdat, Bijan (Supervisor)
    Abstract
    In this thesis, LEON Processor was chosen for its compatible architecture that can be implemented on a wide range of FPGAs. The final designed processor is aimed to conquer soft and hard errors that occur due to cosmic radiations in SRAM cells of an FPGA. The system can finally resist all single SEUs that happen in flip flops and all 4 random errors that take place in each register of the register file. All the flip flops and latches are protected using a TMR scheme. The information redundancy in the regiester file to overcome all 4 random errors is 168% and the errors are corrected by means of a mechanesim that is masked from the processor core. In cache memory, each 32 bit data is...