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    Flexibility Analysis in Supply Chain by Using Design Structure Matrix

    , M.Sc. Thesis Sharif University of Technology Yousefi, Zahra (Author) ; Malaek, Mohammad Bagher (Supervisor)
    Supply chains are socio-technical engineering systems which now days perform in more uncertain operational environment than before. These systems have been vulnerable because of increasing the number of natural disasters, competitiveness and changing the demand. So these systems in order to be survived in such high uncertain environment need to enhance some capabilities in their structure. In this research by considering an assumed auto supply chain, we try to develop an approach to cover uncertainties in operational environment of this system. At the next step, we use design structure matrix modeling to model the interactions between system elements before and after scenario occurring.... 

    Directed Evolution of the Asparaginase Enzyme to Alter Substrate Specificity

    , M.Sc. Thesis Sharif University of Technology Yousefi, Danial (Author) ; Kalhor, Hamid Reza (Supervisor)
    Asparagainase is a therapeutic enzyme which has been a subject of research for decades. The enzyme catalyzes the hydrolysis of the amide group in asparagine and similar amides. Altering the substrate specificity and stabilization of this enzyme can increase its therapeutic properties. Moreover, asparaginases may be evolved to catalyze the hydrolysis of other similar compounds. These can be achieved through directed evolution and computational methods.In this study, the gene encoding L-asparaginase II enzyme from E. coli was amplified by polymerase chain reaction (PCR) and was cloned into an expression vector. The recombinant protein was expressed by an appropriate host secreting the... 

    Hardware Implementation of Fuzzy Logic for Turbojet Engine Fuel Control System

    , M.Sc. Thesis Sharif University of Technology Yousefpour, Hossein (Author) ; Montazeri, Morteza (Supervisor) ; Kazemzadeh Hannani, Siamak (Co-Advisor)
    Gas turbine engine control is a demanding task that requires the regulation of the thrust as well as the satisfaction of the limitations such as engine aerodynamic instability, over temperature and over speed. Fuzzy logic is an attractive technique for the control of poor understood unmodeled, or complex systems especially where the experience of human operators is available to provide qualitative rules. In such cases, it has been found that control decisions can be made on the basis of linguistic measures or fuzzy algorithms. The controller that is designed on the basis of this theory is called fuzzy logic controller. The main objective of this thesis is hardware implementation of fuzzy... 

    Simulation of Microcapsule Formation for Cell Encapsulation Application

    , M.Sc. Thesis Sharif University of Technology Yaghoobi, Mohammad (Author) ; Saeedi, Mohammad Saeed (Supervisor) ; Kazemzadeh Hanani, Siamak (Co-Advisor)
    Co-culture of different cells is necessary for cancer spheroid formation in preclinical drug tests. It is possible to produce thousands of micro-droplets containing different cells, i.e. microcapsules, in a short time, using droplet microfluidics. However the homogeneity of the cell numbers in the droplets has remained as an unsolved problem.Despite the large amount of experimental efforts to reduce the number of undesirable microcapsules, no one tried to utilize the ease of computer aided simulation for investigating different parameters. In this study, we develop a novel method for capturing cell encapsulation using CFD simulations. The effect of the cell suspension inhomogeneity and... 

    Dynamic Model Identification of a 4th Generation Turbojet Engine’s FCU Using Parametric Frequency Response Analysis

    , M.Sc. Thesis Sharif University of Technology Yazdani, Amin (Author) ; Banazadeh, Afshin (Supervisor)
    In this thesis, dynamics of a turbojet’s fuel control unit is studied for the nature and the range of its inputs and outputs. Then, inputs and outputs involved in the system identification process are determined. Tools needed for the application of the input and the signal data sampling are recognized, and henceforth, with the appropriate input applied and the frequency-domain system identification process carried out, desired linear transformation functions representing dynamics of the fuel control unit are found. Using these transformation functions, the fuel control unit is simulated to be converted to an electronic control unit  

    Preparing an Integrated Model of Value Engineering and Risk Management in the form of Build-Operation-Transfer (BOT) Projects

    , M.Sc. Thesis Sharif University of Technology Yavari, Behzad (Author) ; Rafiee, Majid (Supervisor) ; Mostafavi, Mostafa (Co-Supervisor)
    Risk management is the systematic application of management policies, procedures and processes related to risk analysis, assessment and control activities. Risk management is the process of documenting the final decisions made and identifying and applying criteria that can be used to bring risk to an acceptable level. Costs have been studied separately as less attention has been paid to the combination of these two factors. In this study, the combined effect of these two factors on projects in the first place and then on construction, operation and transfer projects has been investigated. The statistical population of the present study consists of 250 contractors and employers of... 

    Exergy Analysis of Turbochargen Systems in the Internal Combustion Engines

    , M.Sc. Thesis Sharif University of Technology Goudarzi, Amir (Author) ; Mozafari, Ali Asghar (Supervisor) ; Ali Ehiaee, Mahdi (Supervisor)
    Thermodynamic analysis of a system is a method for recognizing the type of energy transmission between system and surrounding environment. It also helps to find how macroscopic properties of the system change during this process. This analysis is based on first and second laws of thermodynamic. The first law expresses conservation of energy and inspects quantity of energy transmission but doesn’t evaluate quality of energy. The second law expresses quality of energy and the ability of doing work. The analysis that uses both of the laws is named exergy analysis. By exergy analysis the place of useful energy losses in the system can be determined. In this research the exergy analysis of... 

    Design of a Double-Network Hydrogel Scaffold for Cartilage Tissue Engineering

    , M.Sc. Thesis Sharif University of Technology Ganjali, Amir Reza (Author) ; Abdekhodaei, Mohammad Jafar (Supervisor)
    Osteoarthritis has always been one of the most common diseases in middle age because it causes severe pain and inflammation in the joints of the body. Cartilage tissue does not have the ability to repair itself. For this reason, fabricating and designing the most efficient, least-expensive, and most convenient methods for the treatment of cartilage defects is always an important issue. Today, there are surgical and injectable methods to relieve pain and initiate the body's natural healing response. But due to the many disadvantages and limitations of these methods, tissue engineering science has turned to modifying these methods or providing new methods. One of these methods is the use of... 

    Experimental Study of Using Cellulosic Compounds in Tissue Engineering

    , M.Sc. Thesis Sharif University of Technology Golizadeh, Mortaza (Author) ; Vossoughi, Manouchehr (Supervisor) ; Karimi, Afzal (Supervisor) ; Faghihi, Faezeh (Co-Supervisor)
    Fabrication and characterization of different surface charged cellulose electrospun scaffolds including cellulose acetate, cellulose, carboxymethyl cellulose and quaternary ammonium cationic cellulose for biomedical applications have been reported in this research. We describe preparation of cellulosic nanofibers through the electrospinning following deacetylation cellulose acetate. Moreover, surface modification of electrospun cellulose nanofibers is carried out to obtain carboxymethyl cellulose and quaternized cellulose nanofibers, respectively. At last, the structural, morphological, mechanical, swelling, wettability and the cell culture properties of the scaffolds were analyzed and... 

    Evaluating the Changes in the Mean Vector and Covariance Matrix of EDP Distribution for different IM and Ground Motion Selections

    , M.Sc. Thesis Sharif University of Technology Golchin, Pouya (Author) ; Rahimzadeh Rofouei, Fayyaz (Supervisor)
    In this study, the changes in the mean vector and the covariance matrix of engineering demand parameter (EDP) distributions for different intensity measures and ground motion selections is evaluated. Although, the changes in the mean distribution of EDPs have been extensively studied in the literature, but the changes in the covariance matrix of EDPs distributions caused by ground motion selections has not been paid the due attention. In other words, no study has specifically looked into the effect of intensity measure changes on the covariance matrix; therefore, for the purpose of this study, several steel frame models were considered with perimeter special moment resisting frames (SMRF).... 

    Development of a Process Line Engineering Approach Based on Product Line Engineering Methods for Engineering Agent Oriented Methodologies

    , M.Sc. Thesis Sharif University of Technology Golpayegani, Fatemeh (Author) ; Ramsin, Raman (Supervisor)
    Product Line Engineering (PLE) is a well-established discipline in software engineering, and has gained widespread adoption in industry. Software product lines are considered an efficient means for mass production of software systems, and many companies have based their software development processes on PLE principles and practices.
    Situational Method Engineering (SME) has so far been mainly concerned with metamodels and method chunk repositories; through using these means, methodologies are constructed or extended to address the specific requirements of a software development project. A recent development in SME is the introduction of “Process” Line Engineering, which promises new... 

    Investigation of Effective Parameters on Propulsion in a Vortex Engine

    , M.Sc. Thesis Sharif University of Technology Golbafian, Hamid Reza (Author) ; Mozafari, Ali Asghar (Supervisor) ; Saidi, Mohammad Hassan (Supervisor) ; Ghafourian, Akbar (Supervisor)
    Vortex flow is one of the most sophisticated fluid movements in nature which has great industrial and scientific importance. In this dissertation, in order to study the combustion process due to a vortex flow, a new experimental model of a cold wall vortex engine, was designed, fabricated and tested with oxidizer issuing tangentially toward the end of the chamber. The cold wall effect in these chambers is a result of the cool layer of oxidizer which significantly reduces the amount of heat transfer to the chamber’s wall. This experimental model was designed to withstand the massive temperature rise resulting from the usage of Polyethylene as fuel and Nitrous oxide as oxidizer. In a series of... 

    Manufacturing and Characterization of Bone Scaffold Based on TCP

    , M.Sc. Thesis Sharif University of Technology Gorgin Karaji, Zahra (Author) ; Bagheri, Reza (Supervisor)
    Bone scaffolds are combinations of several materials, for achieving suitable properties and usage for replacing with defected bone. In this study, TCP/Agarose scaffolds are fabricated by two different approaches. The first one is using polymer sponge and gel casting technique and the other one is using foaming agent in order to obtain scaffolds with same porosity. The results show that in spite of same structure and porosity, scaffolds have different mechanical properties due to their different morphologies. Compressive strength of the scaffolds which were fabricated using polymer sponge method is 2.25MPa and elastic modulus is 56.8MPa. After coating with Agarose, compressive strength... 

    Friction Power and Appropriate Lubrication System in Rotary (Wankel) Engines

    , M.Sc. Thesis Sharif University of Technology Gerami Kaviri Nejad, Alireza (Author) ; Mozafari, Ali Asghar (Supervisor)
    In this study an internal combustion rotary (Wankel) engine and its specifications is analyzed and the proper lubrication system is described. The acceleration acting on apex seals, and engine speed fluctuations together with the leading and trailing cells gas pressure forces are analyzed in the present work using the second Newton law. The research shows that cell gas pressure effects are important and inclusion of these effects will provide results which are more compatible with the reality and lead to a much more accurate analysis of the system. Theoretical calculations reveal that gas cell pressure forces represent about 78% of the overall calculated force and ignoring these pressure... 

    Design and Implementation of a Voltage Controlled Oscillator For 77GHz Automotive Radar

    , M.Sc. Thesis Sharif University of Technology Kiavar, Amir Arsalan (Author) ; Medi, Ali (Supervisor)
    Wideband mm-wave radars are gaining popularity in automotive applications due to their superiority in harsh weather conditions, high distance resolution, precise velocity measurement, and superior spatial resolution. The primary purpose of this thesis is to design and implement a voltage-controlled oscillator for 77GHz automotive radar applications.Phase noise -as one of the most crucial specifications in VCO design- Phase noise improvement techniques as well as harmonic engineering methods are delineated. Also, an Ocean-based code for ISF simulation is introduced and developed to obviate the need for additional signal processing software so that simulation speed increases... 

    Fabrication and Surface Engineering of Pu-Tio2 Nanocomposites with Improved Mechanical, Surface and Hemocompatibility Properties with Usability in Vascular Tissue Engineering

    , Ph.D. Dissertation Sharif University of Technology Kianpour, Ghazal (Author) ; Baghery, Reza (Supervisor) ; Pourjavadi, Ali (Supervisor) ; Ghanbari, Hossein (Supervisor)
    The main focus of this project is the fabrication of surface engineering scaffolds based on polyurethane and titanium dioxide. The research's aim is the creation of the synergistic properties of TiO2 and PU as a new strategy for engineering artificial autologous blood vessels. In the first section, PU-TiO2 nanocomposites were synthesized by co-insitu synthesis of nanoparticles and polymer. The nanocomposite films were prepared by solvent casting and thermally induced phase separation methods. Mechanical and biological properties of films were compared with pure PU film. In solvent casting method, the outcomes revealed that the rate of endothelialization of the nanocomposite scaffold after 7... 

    Synthesis and Characterization of Nanofibrous Polymeric Composite Containing Two-dimensional MXene and Capable of Drug Release for Tissue Engineering Applications

    , M.Sc. Thesis Sharif University of Technology Koohkhezri, Morvarid (Author) ; Simchi, Abdolreza (Supervisor)
    Nowadays, biocompatible composites are being utilized as scaffolds supporting cell growth promotion and features with the aim of organs regeneration or substitution based on tissue engineering principals. Moreover, in order to improve bioscaffolds features and function, various two-dimensional composite fillers have been under investigation; for instance, Graphene, Boron nitride, Metal dichalcogenides and oxides and black phosphorous and also electrospinning is mentioned as one of the most compatible and conventional processes of scaffold design that is also the main method of fabrication in this study. In addition, it should be pointed that biocompatible polymers and particularly natural... 

    Definition of a Set of Process Patterns and a Generic Meta-Model for Component-Based Development Methodologies

    , M.Sc. Thesis Sharif University of Technology Kouroshfar, Ehsan (Author) ; Ramsin, Raman (Supervisor)
    Although Component-Based Development (CBD) is not a novel approach, it is still extensively used for building various types of software systems, and is expected to remain popular for the foreseeable future. There exist several software development methodologies that support the construction of component-based systems, and the domain has matured over the years. When viewed collectively, CBD methodologies have indeed addressed all the relevant issues; however, none of the methodologies covers all the aspects of component-based software development. A general methodology can resolve this through addressing the deficiencies while being customizable according to the specifics of the project... 

    An Engineering Approach to Software Modeling Language Development

    , Ph.D. Dissertation Sharif University of Technology Kamandi, Ali (Author) ; Habibi, Jafar (Supervisor)
    Nowadays, the essentiality of appropriate modeling languages has become evident, and with the introduction of new concepts such as domain-specific languages, the need for systematic research on designing and engineering new modeling languages has increased significantly. Several modeling languages have been developed and employed over the years, but the area of modeling languages still suffers from the lack of a proper framework: There is a strong need for an engineering framework that specifies the detailed steps of language development, the input and output artifacts of each step, the techniques applicable to each step, and quantifiable methods for quality measurement. From a unified point... 

    Pore Scale Modeling of Fluid-Fluid Intercations During Low Salinity Waterflooding

    , M.Sc. Thesis Sharif University of Technology Kamani, Ahmadreza (Author) ; Ayatollahi, Shahab (Supervisor) ; Mahani, Hassan (Supervisor)

    Recent studies have shown that the injection of low-salinity water would enhance the oil recovery factor for both the core scale and the field test. The evidence obtained from laboratory studies showed that the control of salinity and the composition of injected water has successfully affected the oil release, hence enhancing the oil recovery efficiency. In this method, by changing the type and amount of dissolved ions in the injected water, the water/oil/rock interactions are altered. Based on this, extensive studies have been focused on the mechanisms for the trapped oil release at the pore scale. Several mechanisms have been proposed to explain this phenomenon, which can be divided...