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    Optimization of Coordinated Distribution System by Adopting the Network Marketing and Traditional Channel

    , Ph.D. Dissertation Sharif University of Technology Shafiei, Mahdi (Author) ; Modarres, Mohammad (Supervisor)
    Abstract
    Nowadays network marketing has promoted marketing, sale and customer relationship altogether. On the other hand, due to the growth of internet, network marketing has become a powerful and attractive channel that can be utilized alongside the other traditional channel. Pricing and network marketing structure influences on distribution system coordination and networker motivation in network marketing. This thesis provides a framework to study the integration of network marketing with retailers in a dual channel distribution system and provide the pattern for determining the different variables of distribution systems, including of product price in diverse channels, commission payment to... 

    Experimental Investigation of the Effects of Asymmetrical Grooves on Thermosyphon Heatpipes

    , M.Sc. Thesis Sharif University of Technology Bahmanabadi, Amir (Author) ; Behshad Shafiei, Mohammad (Supervisor)
    Abstract
    technologies for cooling of electronic devices, have high efficiency due to the heat transfer in two-phase state. In this project, experimental effects of asymmetric triangle groove has been studied on the boiling fluid and effect of the motion on the boiling and heat pipe. Therefore, the experiment has been done by 3 heat pipes and each with 3 plates. The plates consist of a smooth plate, a plate with triangle groove and a plate with rectangle groove. Each heat pipe was filled by methanol in volumetric percentage from 10 to 60. The results show that 20 percent methanol is the optimum for all kind of heat pipe, which has been used. In addition, it is shown that heat pipe with triangle groove... 

    Experimental and Modeling Investigating of Foam Flow Behavior Stabilized by Nanoparticles in Porous Media

    , M.Sc. Thesis Sharif University of Technology Shafiei, Yousef (Author) ; Ghazanfari, Mohammad Hossein (Supervisor)
    Abstract
    Gas injection as an enhanced oil recovery (EOR) method usually suffers from low recovery efficiency. The low viscosity and density of gas as well as reservoir heterogeneity are the main reasons of early breakthrough and override of gas in oil reservoirs. To mitigate the poor sweep efficiency of gas injection, surfactants can be co-injected or injected in an alternating manner with gas to form foam within the reservoir rock. The foam formation can reduce the mobility of the injection fluids in porous media. A significant challenge of foam injection is the stability of the foam in formations and the foam liquid drainage rate is one of the key factors which characterize or show the efficiency... 

    Modeling and Dynamic Analysis of Anti-Lock Braking System Modulator

    , M.Sc. Thesis Sharif University of Technology Shafiei, Mohammad Javad (Author) ; Behzad, Mahdi (Supervisor)
    Abstract
    Anti-lock brakes car as one of the most fundamental and vehicle stability control system is considered. Solenoid valves, one-way valves, Accumulator, damper orifices and other components is a crucial role in the anti-lock system performance, so that the performance of the system and thus affect the dynamic performance of the vehicle. This is the most important part of the anti-lock brake System and These components are all new brake system.In this study a complete modeling of hydraulic control unit and obtain sufficient data to model the dynamic behavior of the hydraulic control unit to be seen. operators working in higher frequencies are weak and virtually reached saturation and efficient... 

    Correction of Time-Dependent Origin-Destination Demand in Dynamic Traffic Assignment

    , M.Sc. Thesis Sharif University of Technology Shafiei, Mohammad Sajjad (Author) ; Zakaei Ashtiani, Hedayat (Supervisor)
    Abstract
    Time-dependent origin-destination demand is a key input in dynamic traffic assignment in advanced traffic management systems, and the result of dynamic traffic assignment is dependent on the accuracy of this information. One method to achieve time dependent demand matrices is using a primary demand matrix and volume traffic counts in some links of network. In this thesis a bi-level model is used to correct the demand matrix and the extended gradient method is suggested to solve the problem. The extended gradient is an iterative method that in each iteration, corrects the demand matrix in a way that the estimated traffic flow be close to the observed traffic flow. Execution of this method in... 

    Effect of Co Doping on Crystal and Electronic Structure of BaFe2-xCoxAs2

    , M.Sc. Thesis Sharif University of Technology Shafiei, Manouchehr (Author) ; Khosroabadi, Hossein (Supervisor) ; Akhavan, Mohammad (Supervisor)
    Abstract
    The discovery of the iron-based superconductors attracted much experimental and theoretical attention in the recent years. BaFe2As2 is one of the highlighted materials which is the antiferromagnetic metal (below Neel temperature) and undergoes to superconducting and non-magnetic state by variety of doping, usually accompanied by a structural phase transition. Superconductivity is appeared in this system by doping Co and Ni at the Fe sites which is one of the excited situations in the physics of superconductors, where the magnetic doping suppresses the superconducting state. So, the study of Co doping of the electronic structure of this system, might lead us to better understanding of the... 

    An experimental and computational study on the rate constant of electrochemically generated n-acetyl-p- quinoneimine with dimethylamine

    , Article International Journal of Electrochemical Science ; Vol.3, Issue 10 , September , 2008 , PP. 1092-1107 ; 14523981 Shafiei, H. (Hadi) ; Haqgu, M. (Mohammad) ; Nematollahi, D. (Davood) ; Gholami, M. R. (Mohammad Reza) ; Sharif University of Technology
    2008
    Abstract
    Electrochemical oxidation of acetaminophen (N–acetyl–p–aminophenol) (1) has been studied in the presence of dimethylamine (2) as a nucleophile in aqueous solution, by means of cyclic voltammetry and controlled-potential coulometry. The results indicate the participation of electrochemically generated N-acetyl-p-quinoneimine (1a) in Michael reaction with dimethylamine (2). Based on ECE mechanism, the observed homogeneous rate constant (kobs) of the above mentioned reaction is estimated by comparing the experimental cyclic voltammograms with the digital simulated results. Further more; kinetics and mechanism of the reaction were studied with ab initio calculation, Monte Carlo and QM/MM... 

    Development of Model for Evaluation of Energy Technologies and R&D Planning

    , Ph.D. Dissertation Sharif University of Technology Shafiei, Ehsanoddin (Author) ; Ghofrani, Mohammad Bagher (Supervisor) ; Saboohi, Yadollah (Supervisor)
    Abstract
    In this research work an analytical instrument has been developed for assessment of energy technologies, R&D resource allocation and technology development. Development of new technologies has been considered according to the specific conditions of developing countries. The analytical instrument includes two models interlinked with each other: energy technology assessment and optimal control of innovation activities. Energy technology assessment and prioritization of new energy technologies are provided by the model of the energy supply system that contains a detailed representation of current and emerging technologies characterized in terms of their technical indices. The results of this... 

    Design and Analysis of an Improved System for Recovering Ventilated Air Heat in DX HVAC Systems

    , M.Sc. Thesis Sharif University of Technology Jafarinejad, Tohid (Author) ; Roshandel, Ramin (Supervisor) ; Shafiei, Mohammad Behshad (Co-Advisor)
    Abstract
    In the last three decades, the world has experienced enormous increases in energy consumption as a consequence of the economic and population growth. This causes renewable energy and energy recovery to become a requirement in building designs rather than option. A direct expansion (DX) air conditioning system is an efficient way to supply fresh and dehumidified air to a built environment a long side it plays a key role in preventing the spread of respiratory diseases. To improve the efficiency of a conventional DX system in hot and humid regions, fresh air dehumidification and conditioning systems with energy recovery measures are the key equipment to reach such a goal. To achieve this goal... 

    Building Management System (BMS) for Sharif Energy Research Institute

    , M.Sc. Thesis Sharif University of Technology Joudzadeh, Amin (Author) ; Rajabi Ghahnavieh, Abbas (Supervisor) ; Shafiei, Mohammad Behshad (Supervisor)
    Abstract
    The ever-growing demand for energy has raised concerns on sustainability of energy supplies and their environmental impact. Energy efficiency in buildings has gained special interest due to its energy consumption share in national scale. One of the most promising approaches for reducing building’s energy consumption is using an intelligent building management system (BMS). These systems have proved to reduce energy consumption while increasing comfort, and hence have gained global, and more recently national, recognition. This research has been devoted to the development of an intelligent building management system for the building of Sharif Energy Research Institute (SERI). The proposed... 

    Experimental study on macro segregation behavior in short and wide range solidification of different aluminum alloys

    , Article Materials Science and Technology Conference and Exhibition 2013, MS and T 2013 ; Volume 2 , 2013 , Pages 822-829 ; 9781629933092 (ISBN) Shafiei Zadeh, B ; Mohammad Salehi, E ; Hassan Nejad, H ; Shafiei Zadeh, S ; Sharif University of Technology
    2013
    Abstract
    Data are presented on the solidification of aluminum alloys and their macro segregation behavior. Three alloys with different solidification ranges were prepared in two temperatures. Two types of molds were also prepared by sand and metallic materials. The solidification of Al alloys were studied and the effects of four parameters were determined, including cooling rate, casting temperature, degassing and nucleation effects on solidification and a comparison was conducted to Scheil model performance. Three types of aluminum alloys (Al-12.1%Si, Al-6.9%Si and Al-4.4% Cu) with short, medium and wide solidification ranges were studied and the results showed that degassing, nucleation, increasing... 

    A new model for the effect of grain size on the elastic modulus of nanocrystalline materials

    , Article Materials Science- Poland ; Volume 27, Issue 1 , 2009 , Pages 279-285 ; 01371339 (ISSN) Ali Shafiei, M ; Sharif University of Technology
    2009
    Abstract
    A new model is developed for the structure of nanocrystalline materials. Based on the developed model, a new approach for investigating the effect of grain size on the elastic moduli of nanocrystalline materials is introduced. The predictions of the model are strongly correlated with the experimental results reported in the existing literature  

    Face Forgery Detection Through Statistical Analysis and Local Correlation Investigation

    , M.Sc. Thesis Sharif University of Technology Asasi, Sobhan (Author) ; Ghaemmaghami, Shahrokh (Supervisor) ; Amini, Sajjad (Supervisor)
    Abstract
    Existing face forgery detection methods mainly focus on certain features of images, such as features related to image noise, local textures or frequency statistics of images for forgery detection. This makes the extracted representations and the final decision depend on the data in the database and makes it difficult to detect forgery with unknown manipulation methods. Solving this challenge, which is called the generalization challenge in artificial intelligence literature, has become the main goal of researchers in this field. In this thesis, the focus is on extracting effective features for success in forgery detection and preventing the performance of the forgery detection network from... 

    Analytical Investigation and Evaluation of Vulnerability of Deep Networks to Adversarial Perturbations

    , M.Sc. Thesis Sharif University of Technology Azizi, Shayan (Author) ; Ghaemmaghami, Shahrokh (Supervisor) ; Amini, Sajjad (Co-Supervisor)
    Abstract
    One of the most important problems in machine learning is investigating the performance of the learning algorithms, and especially deep neural networks, on adversarial examples, which are generated by imperceptibly perturbing input images, so that cause the model make a wrong prediction. Not only this line of research is important for making deep neural networks dependable, but also can help with understanding the fundamental limitations of deep neural networks, and the nature of their operation, which can in turn provide researchers with valuable insights into artificial intelligence. In this research work, we have tried to approach the topic with a mainly theoretical mindset. The method we... 

    On Some Pancyclicity Properties of OTIS Network

    , M.Sc. Thesis Sharif University of Technology Shafiei, Tayebeh (Author) ; Movaghar, Ali (Supervisor)
    Abstract
    A parallel computer system is composed of a collection of processors used to speed up running a program or performance of multiple programs. If we consider the processors as nodes and the channels between processors as edges, the constructed graph represents an interconnection networks. Network topology affects performance and energy consumption of interconnection network very much. Some parameters of topology quality are low node degree and diameter, high connectivity degree and bisection width and symmetry. Since some of these parameters are in contrast with others, a network with more parameter improvements, is more desirable. Finding cycles with specific length and particularly ... 

    Adding backlash to the connection elements can improve the performance of a robotic exoskeleton

    , Article Mechanism and Machine Theory ; Volume 152 , 2020 Shafiei, M ; Behzadipour, S ; Sharif University of Technology
    Elsevier Ltd  2020
    Abstract
    Kinematic mismatch between exoskeletons and human body results in excess internal forces/torques and hence discomfort as well as increase the power consumption. The connection stiffness has been shown to have potentials for minimizing the kinematic mismatch effects. However, realization of a desired stiffness in the connection element seems difficult if not impractical. In this work, adding controlled backlash to the exoskeleton-body connection is investigated as a possible solution for the kinematic mismatch challenge. A stiffness model which includes backlash parameters was formulated and identified experimentally using three male subjects on a typical lower extremity exoskeleton. A... 

    Optimisation of an integrated parallel distribution system by including network marketing

    , Article International Journal of Logistics Systems and Management ; Volume 36, Issue 2 , 2020 , Pages 305-318 Shafiei, M ; Modarres, M ; Sharif University of Technology
    Inderscience Publishers  2020
    Abstract
    Network marketing is a business model that depends upon a network of distributors for growth, such as in multilevel marketing. A direct selling method features independent agents that make up a distribution network for goods and services. This paper provides a framework to study the network marketing by adopting the traditional channel. To motivate all distributers in network marketing as well as retailers, it is required to design a well-balanced distribution and pricing system. The allocated commission for distributers in different layers of network marketing is part of pricing system, which is vital. In this paper, we develop an approach to determine all elements of system, including... 

    The Concept of Truth in Husserl’s Phenomenology

    , M.Sc. Thesis Sharif University of Technology Shafiei, Mohammad (Author) ; Rashidian, Abdolkarim (Supervisor)
    Abstract
    Concept of Truth is the most fundamental concept in any intellectual activity. Knowledge systems are distinguished, above all, by their different viewpoint about truth and different criteria which they present for determining truth. Phenomenology, that its motto is returning to things as such, should introduce a definition of truth free from the presuppositions which lie in the definitions (implied or expressed ones) of it in most knowledge systems. In this project, we try to clarify concept of truth as correlation of transcendental act in philosophy of Husserl, and also study antecedents and consequents of this conception. In this project we investigate the place of the idea of “truth” in... 

    Investigation on Hydrophobic Particle Mobility in Electrolyte Media under Various Electrokinetic Effects

    , M.Sc. Thesis Sharif University of Technology Shafiei Souderjani, Ali (Author) ; Seeadi, Mohammad Hassan (Supervisor) ; Kazemzadeh Hannani, Siamak (Co-Supervisor)
    Abstract
    Electrophoresis of colloidal and bio-particles, which is the motion of a charged particle under an electric field, is a powerful method for the characterization and separation of particles. Electrophoresis of particles could be in electrolyte and gel mediums. Additional drag force is exerted on the particle in a gel medium due to the 3D polymeric structure. Experimental research and molecular dynamics simulations have shown that the no-slip boundary condition is not valuable for many particles in micro and nano-devices. The Navier slip condition, which represents the amount of slip, must replace the no-boundary condition. Characterization of hydrophobicity for optimal design in microfluidic... 

    Analysis and Enhancement of Low Voltage Ride Through Of Wind Turbines with Brushless Doubly Fed Induction Generator

    , Ph.D. Dissertation Sharif University of Technology Gholizadeh, Mahyar (Author) ; Oraee Mirzamani, Hashem (Supervisor) ; Tohidi, Sajjad (Co-Advisor)
    Abstract
    Wind energy technologies guarantee low pollution and operational costs. Using a DFIG and a fractionally rated power electronics converter gives variable speed operation with a low cost drive train. As energy policy organizations have allocated a considerable quota of wind energy generation to offshore wind farms, the absence of slip rings and brushes in the brushless DFIG (BDFIG) is an advantage for offshore wind turbines where maintenance is vital and expensive. With increasing wind power penetration in power systems, grid code requirements are an important consideration for the ride-through capability of wind farms through voltage dips, particularly for multi- MW wind turbine generators....