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    Probabilistic Modelig of the Earthquake-induced Losses Resulted from the Shock to Capital and Labor

    , M.Sc. Thesis Sharif University of Technology Doroudi, Omid (Author) ; Kashani, Hamed (Supervisor)
    Abstract
    Estimation of indirect economic losses due to natural disasters, especially earthquakes, is one of the essential issues in disaster management. This study presents a framework that uses an economic model of the community under study and calculates the indirect economic losses caused by an earthquake. To this end, first, the earthquake-induced direct economic losses are quantified using appropriate risk analysis models. The direct losses are used to characterize the consequent shock to labor and capital. These shocks are then used as inputs to the regional economic model. In the proposed framework, a Computable General Equilibrium (CGE) model uses various data about the state of the community... 

    The Integrative dam Assessment Modeling for Multidisciplinary Analysis of Costs and Benefits (Case Study: Alavian Dam)

    , M.Sc. Thesis Sharif University of Technology Doroudi, Parvin (Author) ; Abrishamchi, Ahmad (Supervisor) ; Tajrishi, Masoud (Co-Supervisor)
    Abstract
    Despite there are many publications and press on the benefits and costs of dams from a purely single-discipline perspective, but recent studies simultaneously assess biophysical, economic, and social issues as well as concepts related to political geography about dams. The purpose of this study is to model the benefits and costs of constructing a dam from a multi-field perspective. The Integrative Dam Assessment Modeling (IDAM) is designed to integrate biophysical, economic, social and political geography perspectives into a single cost-benefit analysis of dam construction. In particular, a new tool of integrative dam assessment model has been proposed to evaluate the costs and benefits... 

    Fabrication of Graphene-WO3 Nanocomposites as Photocatalyst in the Visible Light Region

    , M.Sc. Thesis Sharif University of Technology Choobtashani, Mohammad (Author) ; Akhavan, Omid (Supervisor)
    Abstract
    WO3 is known as a photocatalyst in the visible light region, but with lower efficiency compared to more interesting semiconductor photocatalysts such as TiO2 and ZnO. Many attempts have been done to increase the efficiency of this photocatalyst by incorporating metal and metal oxide nanoparticles or recently carbon nanotubes.On the other hand, application of graphene, as an unrolled carbon nanotube, for increasing the photocatalytic activity of TiO2 and ZnO has shown positive results. Furthermore, it was reported that such semiconductor photocatalysts (and very recently WO3) can photocatalytically reduce the chemically exfoliated graphene oxide sheets under UV-vis irradiation.
    In this... 

    Synthesize of Graphene Nanoribbons with a Non-Zero Energy Band Gap for Inactivation of Alive Cells Using Infrared Irradiation

    , M.Sc. Thesis Sharif University of Technology Emamy, Hamed (Author) ; Akhavan, Omid (Supervisor)
    Abstract
    Graphene is a one layer atom thickness and zero energy gap so for using it in nano electronic and transistors baised on graphene it's energy gap should be opened.one of the methods for opening graphene band gap is creating nano scale boundaries or synthesize graphene nanoribbons. One of the new methods for graphene nanoribbon synthesize is longitudinal opening of carbon nanotube. In this thesis graphene nanoribbons synthesize with this method and analyze with AFM and Raman spectroscopy. Carbon nanotubes also have energy gap and IR absorption recently they used for living cell destruction. In this thesis we synthesize graphene nanoribbons and analyzing their optical absorption and use it for... 

    Fabrication of Graphene/TiO2 Nanowalls as Visible Lights Photocatalysts

    , M.Sc. Thesis Sharif University of Technology Rahimi, Kourosh (Author) ; Akhavan, Omid (Supervisor)
    Abstract
    TiO2 is known as a photocatalyst in near UV-Visible light region with better efficiency compared to other semiconductor photocatalysts. Many attempts have been done to increase the efficiency of this photocatalyst. also, application of 2D carbon nanostructures namely graphene for increasing the photocatalytic activity of TiO2 has shown positive results.
    In this research, we first synthesized Graphene Oxide (GO) suspension by exfolation of graphite oxide suspension. then we fabricated TiO2 thin films on glass substrates by so-called sol-gel method. finally we fabricate Graphene Oxide/TiO2 nanowalls composite films as a photocatalyst in visible light. X-ray photoelectron spectroscopy... 

    Synthesis of Graphene Nanosheets for Stem Cells Applications

    , M.Sc. Thesis Sharif University of Technology Shahsavar, Mahla (Author) ; Akhavan, Omid (Supervisor)
    Abstract
    Graphene nanogrids fabricated by graphene nanoribbons obtained through oxidative unzipping of multi-walled carbon nanotubes, used as two-dimensional selective templates for accelerated differentiation of human mesenchymal stem cells (hMSCs), isolated from umbilical cord blood, into osteogenic lineage. The biocompatible and hydrophilic graphene nanogrids showed high actin cytoskeleton proliferations that coinciding with patterns of the nanogrids. The amounts of proliferations found are slightly better than proliferation on hydrophilic graphene oxide (GO) sheets, and significantly higher than non-uniform proliferations on hydrophobic reduced graphene oxide (rGO) sheets and polydimethylsiloxane... 

    Synthesis of Graphene from Waste by Chemical Exfoliation and Study of It’s Physical Characteristics

    , M.Sc. Thesis Sharif University of Technology Mirsepah, Ali (Author) ; Akhavan, Omid (Supervisor)
    Abstract
    One atom thick layer of pure carbon in bonded and hexagonal lattice is named graphene. graphene has unique mechanical, optical, thermal and electrical properties and because of these properties has grabbed attention. graphene has been made from high pure graphite by different methods such as CVD(chemical vapor deposition) , chemical exfoliation , micromechanical cleavage and colloidal suspension. through these methods, green methods for synthesis of graphene, using eco-friendly reductants during synthesis of graphene instead of hydrazine and recently using waste(not graphite) are attractive for synthesis of graphene. Following this idea , a group has produced graphene from wastes such as... 

    Synthesis of Graphene Oxide and Study of its Fluorescence Properties

    , M.Sc. Thesis Sharif University of Technology Akbari, Ebrahim (Author) ; Akhavan, Omid (Supervisor)
    Abstract
    Graphene oxide is a single sheet of Carbon atoms which has been arranged on a two-dimensional honeycomb lattice. Functional groups such as epoxy, carboxyl and carbonyl are located on basal plane and at the edges of graphene oxide and they localize electrons on the surface of graphene oxide and open band gap in its band structure. Pure graphene has zero band gap, so existence of fluorescence properties is unlikely; but graphene oxide has fluorescence properties due to band gap in its band structure. Fluorescence properties of graphene have been used in live cell imaging and drug delivery, so study and increasing of fluorescence properties is significantly important. The purpose of this... 

    The Use of Hydrogen Rich Water for Synthesis of Hydrogenized Graphene and Investigation of Its Properties

    , M.Sc. Thesis Sharif University of Technology Ghorbani, Fatemeh (Author) ; Akhavan, Omid (Supervisor)
    Abstract
    Graphene is a two dimensional lattice which is created from carbon atoms. Having special feature, it has such various medical usage, for example in diagnosing and treating cancer. Adding a particular factor to graphene could improve their efficiency. In comparis on with graphene itself, graphene oxide and reduced graphene oxide are much more successful in diagnosing and treating than others because of their higher hygroscopic. Recent studies state that hydrogenized combinations including hydrogenized graphene show desired results. Due to its higher hygroscopic and the possibility of adherence to the cells, hydrogenized graphene could be very effective in diagnosing and treating the sarcomas.... 

    A Meta Heuristic Approach for Design of a Network System in Mass Customization

    , M.Sc. Thesis Sharif University of Technology Puresmaili, Ehsan (Author) ; Fattahi, Omid (Supervisor)
    Abstract
    This study discusses about mass customization and optimization of supply network in which both goal considering to set the flow of raw material and final product to satisfy the customer demand. The mass customization is more important concept in this study, so that this goal is placed to the first objective. In this research, the model which contained both goal is presented. The model focus on mass customization and try to satisfy various products demand, which constitute 3 kind of speed demands. Each product can satisfy in 3 way: fast, normal, slow.In the first model the new approach present in which the speed affects all of supplying, manufacturing and distributing system. The system try... 

    Identifying the risks of Iranian Knowledge BasedFirms Using Fault Tree Analysis (FTA)

    , M.Sc. Thesis Sharif University of Technology Sarhadi, Maryam (Author) ; Fattahi, Omid (Supervisor)
    Abstract
    Knowledge Based Firms are considered to be important for the economic development of a country in regards to both employment growth and innovative activity. The latter is believed to contribute significantly to the increase in productivity and therefore the competitiveness of Iran’s economy. This study contributes to the above literature by investigating the factors that are believed to treat the growth of such firms in Iran. The purpose of this study is to identify functional risks of vital signs monitors via Fault Tree Analysis (FTA) method to use as a guide for manufacturers to identify and control hazards. Therefore, 30 knowledge based firms were selected as sample. Then, based on a... 

    A Novel Reliability Model for Information Technology Web services

    , M.Sc. Thesis Sharif University of Technology (Author) ; Fatahi Valilai, Omid (Supervisor)
    Abstract
    The Internet is often used for communication-based applications such as online banking, stock trading, and shopping where service interruption is unacceptable. Thus, analysis of the impact of the failures of hardware, software, and related services’ performance quality of the service provided to users is of importance to designers and managers in these functions. In this study, we developed a strategy to the design of a dynamic combination of file servers with the aim of providing reliability and SLA. At first, we examine the reasons for the violation of service level in file host services and datacenters, and then we introduce the criteria to measure the violation of service level on the... 

    Fabricating Graphene Paper and Determining Its Electrical and Mechanical Properties and Using It for Proliferation and Differentiation of Neural Stem Cells

    , M.Sc. Thesis Sharif University of Technology Akbar Shirazian, Soheil (Author) ; Akhavan, Omid (Supervisor)
    Abstract
    Nowadays, tissue engineering and stem cells-based therapies have outlined a promising prospect in neural networks regeneration. But it usually requires biocompatible and conductive scaffolds for culturing neural stem cells and directing their differentiation toward the neurons. Graphene due to its unique physical and chemical properties has attracted much interest in tissue engineering. For this purpose, in this study biocompatible graphene oxide foams have been used for neural stem cell culturing. For the first time, graphene oxide foam were fabricated by precipitation of chemically exfoliated graphene oxide sheets in an aqueous suspension onto the PET substrate at ~80 oC under UV... 

    Product Portfolio Management Using Life Cycle Considerations

    , M.Sc. Thesis Sharif University of Technology Ebrahimian, Mahsa (Author) ; Fattahi, Omid (Supervisor)
    Abstract
    Today’s organizations always encounter limitations on the way of achieving their goals. Budget constraint, inventory constraints, capital constraints are issues which complicates management decision making.
    Global market has enabled manufacturers compete globally. Even position their factories in other countries and use of competitive advantages and other markets demand. This is why decision making in production and manufacturing domain has been complicated. Decision making in production and manufacturing should become faster and more precise in order to keep market competitiveness. Organization should make long term or strategic decisions and short term decisions about keeping the... 

    Development of a novel solution to enable integration and interoperability for cloud manufacturing

    , Article 6th International Conference on Changeable, September 2016 through 6 September 2016 ; Volume 52 , 2016 , Pages 6-11 ; 22128271 (ISSN) Delaram, J ; Fatahi Valilai, Omid ; Sharif University of Technology
    Elsevier B. V  2016
    Abstract
    Nowadays, manufacturing enterprises have been faced with a globalized competitive environment. In this fierce condition, Cloud Manufacturing paradigm emerged as a promising concept for competition. It provides effective solutions and tools for manufacturing enterprises to collaborate in globalized market. The revolution that Cloud Manufacturing has created is based on the redefinition of the classic methods to those which are appropriate for todays' modern and globalized manufacturing environments. In parallel with cloud-based revolution, the expansion of internet-based technologies has been started. These technologies previously have been applied in many fields and resulted in... 

    Synthesis of Graphene Nanosheets for Application in Biosensors

    , M.Sc. Thesis Sharif University of Technology Rahighi Yazdi, Reza (Author) ; Akhavan, Omid (Supervisor)
    Abstract
    Graphene, the newborn nanomaterial whose unique properties has extensively drawnattention of many scientists in the recent years, is an ideal candidate for sensing applications due to its exclusive properties like extremely high specific surface area, excellent electrical conductivity, andcapability of being easily functionalized. In this research, after reviewing the attempts already performed on detection of DNA, in order to detect the four bases of DNA (G, A, T, and C) via electrochemical approach, graphene nanosheets were synthesized by the popular Hummer’s method and were deposited on a graphite rod by electrophoretic deposition with a vertical preferred orientation. To eliminate the... 

    Numerical Modeling of Contact-Impact Problems Using Polygonal Finite Element Method

    , Ph.D. Dissertation Sharif University of Technology Biabanaki, Omid Reza (Author) ; Khoei, Amir Reza (Supervisor)
    Abstract
    A Polygonal finite element method without conforming mesh was introduced by the authors for modeling large deformation elastoplastic problems. In this method, the geometry and interfaces of the problem are modeled on a uniform mesh. The boundaries are defined on the uniform background mesh using the level set method. Different polygonal elements will be created at the intersection of the interface and the uniform mesh. Polygonal element shape functions are used for the interpolation. In this paper, the capability of this polygonal finite element approach for modeling large deformational frictionless dynamic contact-impact problems is investigated. Contact interfaces are modeled independent... 

    Strategic Requirements of Petroleum Upstream Supply Chain Management

    , M.Sc. Thesis Sharif University of Technology Khorrami, Hamed (Author) ; Fatahi Valilai, Omid (Supervisor)
    Abstract
    Nowadays the concept of competition in business has been expanded from enterprises to supply chains. For success in this competitive environment, it should be established complete coordination and synchronization between different rings of the chain in both strategy and operations. The supply chain management is a factor for achieving to this purpose. Effective supply chain management, especially in complex supply chains like petroleum upstream supply chain, requires to strategic factors that propel the chain to the long term goals. Unfortunately, it is showing off the vacancy of attending to this case in the literature. This thesis tries to fill this gap in literature with a new approach... 

    Propose a Model to Minimize Energy Consumption in Turning Machining Operations

    , M.Sc. Thesis Sharif University of Technology Fazli, Erfan (Author) ; Fatahi-Valilai, Omid (Supervisor)

    The Fabrication and Characterization of Graphene by Mechanical Exfoliation Method and a Review on Graphene Field Effect Transistors

    , M.Sc. Thesis Sharif University of Technology Rostami Osanloo, Mehrdad (Author) ; Akhavan, Omid (Supervisor)
    Abstract
    Graphene is a semiconductor with zero band gap. Due to electron ballistic transportation and having a single atom thickness of graphene, it is counted as an ideal material in Nano-electronic industry and essential candidate for fabrication of next generation of transistors. The Fermi level in graphene is located between Conduction and valance bands in a Dirac point. Due to low resistance, graphene has a substantial sensitivity near the Dirac point to local carrier density changes. This feature makes delicate detection of electromagnetic waves and gas sensing by graphene field effect transistors (GFETs). In this thesis, fabrication and characterization of graphene field effect transistor on...