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    Proceedings of the first Regional Conference on Magnetic and Superconducting Materials (MSM-99); Tehran, Iran, 27-30 Sept. 1999

    , Book Regional Conference on Magnetic and Superconducting Materials (1st: 1999: Tehran, Iran) ; Akhavan, M ; Jensen, J ; Kitazawa, K
    World Scientific  2000

    Analysis and data-based reconstruction of complex nonlinear dynamical systems : using the methods of stochastic processes

    , Book Rahimi Tabar, M. Reza
    Springer International Publishing  2019
    Abstract
    This book focuses on a central question in the field of complex systems: Given a fluctuating (in time or space), uni- or multi-variant sequentially measured set of experimental data (even noisy data), how should one analyse non-parametrically the data, assess underlying trends, uncover characteristics of the fluctuations (including diffusion and jump contributions), and construct a stochastic evolution equation?
    Here, the term "non-parametrically" exemplifies that all the functions and parameters of the constructed stochastic evolution equation can be determined directly from the measured data.
    The book provides an overview of methods that have been developed for the analysis of... 

    Sustainable Analysis of Unions Uses Axiomatic Design Theory with Focus on European Union

    , M.Sc. Thesis Sharif University of Technology Torbati, Mostafa (Author) ; Malaek, S. M (Supervisor)
    Abstract
    In this project, we examine the stability or sustainability issue in unions, in other words we want to know whether integration in European Union is stable? Countries have positive attitude toward unions and being member in unions is at special priorities. The main reason for countires is improve economy and national Security.
    The main question in this research is modeling European Union with Axiomatic Design Theory and analysis of sustainability based on this theory. This study has attempted to push Axiomatic Design Theroy in the new field of Systems Engineering and also it gives a new and differnet approach to stability.
     

    , M.Sc. Thesis Sharif University of Technology (Author) ; Golshani, M (Supervisor)
    Abstract
    Most of local thinkers ,who were influenced by Western philosophers of science, and have spoken about religious knowledge, have selected experimental science as standard science and Have tried to find a way trough cultural and other non-scientific channels of science to influence the field of human knowledge by religious teaching's .This expert's are generally opposed to positivist’s models of science, but because of the nature of the Western atmosphere that they breathe, consider the experimental science as the main model of knowledge and the experience as the main method of Acquisition of knowledge. Paya is also one of this thinkers who is influenced by Karl Popper's ideas about the... 

    Real-Time Fusion of Asynchronous Data in Distributed Sensor Networks

    , Ph.D. Dissertation Sharif University of Technology Talebi, Hadi (Author) ; Hemmatyar, A. M. Afshin (Supervisor)
    Abstract
    Real-time asynchronous data fusion for high-speed phenomena is an important and challenging task in the sensor networks. Examples of data fusion applications in sensor networks are: managing the traffic of maneuvering airplanes and ground vehicles in airside areas of an airport, traffic management in streets and roads, Driver Assistance Systems, guidance of antiaircraft and antimissile missiles. In all the data fusion applications the estimation of the required variables is necessary.
    In this research two methods are introduced for real-time asynchronous data fusion, especially for track-to-track fusion of high-speed phenomena in sensor networks. The effectiveness and usability of these... 

    Proposed Method for Selecting the Most Suitable Contractor Using Risk Analysis

    , M.Sc. Thesis Sharif University of Technology Shakiba Zahed, Hadi (Author) ; Mortaheb, Momamad Mehdi (Supervisor)
    Abstract
    At present, with some exceptions, the contracts are awarded based on the least proposed price. The records show that this method has not been successful especially for the infrastructure projects. In other words the projects awarded this way have been completed with time and cost overruns. Most of the times, such projects have not satisfied the stakeholders' expectations or have had problems during operation phase. The goal of this research is to suggest a method for selecting the most suitable contractor, considering the proposed price as well as incorporating the delay and other risks based on Contractors' actual past performance in the completed projects. Before selecting the Contractor,... 

    Light Duty Vehicles' Emission Reduction Potentials in Megacities
    Using New Powertrain Technologies (Case Study: Tehran)

    , M.Sc. Thesis Sharif University of Technology Askariyeh, Mohammad Hashem (Author) ; Erhami, M. (Mohammad) (Supervisor) ; Pourzahedi, H. (Hossein) (Supervisor)
    Abstract
    Tehran is one of the most polluted megacities in the world, and based on different studies, vehicular sources are responsible for most of the criteria pollutant emissions in this city. The number of vehicles on the streets has been increased drastically leading to growing amount of emission and this trend is continuing. In order to reduce the amount of vehicular emission, it is vital to investigate the factors affecting vehicles emission in this city. This could help to find efficient solutions to improve the situation. Hence, a low-cost methodology to estimate the vehicular emissions is developed. In this... 

    Modeling and Analysis of the Powder Deposition Mechanisms of Selective Laser Sintering Process

    , M.Sc. Thesis Sharif University of Technology Shakiba, Abdorreza (Author) ; Movahedi, Mohamad Reza (Supervisor)
    Abstract
    Selective laser sintering is a technique which uses a laser as the power source to sintering some selected points at a bed of powder in order to create a solid structure. In this research the SLS mechanisms of powder deposition is simulated and surface smoothness and layer density created by each mechanism is computed. For this purpose roller, blade and hopper mechanisms are simulated. For this simulation, polyamide 12 (PA2200) which is a common material is used. In this simulation at first powder specifications are extracted according to the references and for particle shape instead of using the spherical particle shape we use a certain shape that is more close to reality which created by... 

    Energy Optimization of an Arm with Seven Degrees of Freedom Using Imperialistic Competitive Algorithm (ICA) and Designing an Artificial Neural Network

    , M.Sc. Thesis Sharif University of Technology Abedini, Amin (Author) ; Ahmadian, M.T (Supervisor) ; Asghari, M (Supervisor)
    Abstract
    In recent years, great attention has been devoted to the design of artificial arms. The most crucial problem in such a design is the trajectory of movement. In this paper, a seven degree of freedom arm is modeled and simulated. Also, the optimization method named “Imperialistic Competitive Algorithm” has been modified and better performance of the new version is presented. Energy optimization is performed based on trajectory of the arm with angular velocity, angular acceleration and joint angles using modified imperialistic competitive algorithm (ICA). Considering ICA as a fast optimization algorithm, it would be reasonable to use this algorithm for robotic purposes for online answering. The... 

    Fabrication of Al Based Nanocomposite with Al2O3 and Al3Ti Reinforcements by Mechanical Milling and Press and Sintering (In situ method) and Investigation of Its Wear Behavior

    , M.Sc. Thesis Sharif University of Technology Shabani Nezhad, Parisa (Author) ; Seyed Reihani, M (Supervisor)
    Abstract
    In this study, Aluminium based nanocomposite with Al3Ti and Al2O3 nanoparticles have been elaborated by mechanical alloying. For this purpose, Al and TiO2 powders have been blended with weight ratios of 10, 20 and 30 percents and were milled using a planetary mill. Morphological variations in different timing periods of mechanical milling process was investigated by Scaning Electron Microscopy (SEM) and The optimal times for alloying were determined for each combination. The pure Aluminium and the powder with 10, 20 and 30%wt reinforcement had coax morphology after respectively for 44, 30, 24 and 14 hours. after studing phase transformations by XRD analysis, the final powders were cold... 

    Jahn-Teller Effect in Diamond Vacancy Under Stress

    , M.Sc. Thesis Sharif University of Technology monfared, Mohammad (Author) ; Vesaghi, M. A (Supervisor) ; Babamoradi, M (Co-Advisor)
    Abstract
    Electron states of diamond vacancy under stress were studied theoretically. The generalized Hubbard model is used to calculate the electrons energy levels. The results shows that the degeneracy of some levels (T, with triple space degeneracy) reduced to levels with lower degeneracy (E, with double space degeneracy and A, without degeneracy). Besides this spiting of degeneracy the energy of all states changed and therefore the transition energy between these states changed too. Jahn-Teller effect was observed  

    Antioxidant, antifungal, water binding, and mechanical properties of poly(vinyl alcohol) film incorporated with essential oil as a potential wound dressing material

    , Article Journal of Applied Polymer Science ; Vol. 131, issue. 20 , 2014 Kavoosi, G ; Nateghpoor, B ; Dadfar, S. M. M ; Dadfar, S. M. A ; Sharif University of Technology
    2014
    Abstract
    In this study, the properties of poly (vinyl alcohol)(PVA) films incorporated with Zataria multiflora essential oil (ZMO) as a potential antioxidant/antibacterial material was investigated. PVA films were prepared from PVA solutions (2% w/v) containing different concentrations of ZMO. Water solubility, moisture absorption, water swelling, and water vapor permeability for pure PVA films were 57 ± 1.1, 99 ± 3.2%, 337 ± 8%, and 0.453 ± 0.015 g mm/m2 h, respectively. Incorporation of ZMO into PVA films caused a significant decrease in water swelling and moisture absorption and increase in solubility and water vapor permeability. Tensile strength, elastic modulus, and elongation at break for pure... 

    Transport and deposition of pharmaceutical particles in three commercial spacer-MDI combinations

    , Article Computers in Biology and Medicine ; Vol. 54 , 2014 , pp. 145-155 ; ISSN: 00104825 Yazdani, A ; Normandie, M ; Yousefi, M ; Saidi, M. S ; Ahmadi, G ; Sharif University of Technology
    2014
    Abstract
    Respiratory drug delivery has been under the research spotlight for the past few decades, mainly due to the high incidence of pulmonary diseases and the fact that this type of delivery offers the highest efficiency for treatment. Despite its invaluable benefits, there are some major drawbacks to respiratory drug delivery, the most important of which being poor delivery efficiency and relatively high drug deposition in undesirable regions, such as the mouth cavity. One way to improve the efficiency of respiratory drug delivery with metered-dose inhalers is placing a respiratory spacer between the inhaler exit and the mouth. It is argued that high drug deposition in the immediate airways of... 

    Homoleptic tetraazaphenanthrene-based copper(I) complexes: Synthesis, spectroscopic characterization, crystal structures and computational studies

    , Article Inorganica Chimica Acta ; Vol. 423, issue. PA , 2014 , pp. 348-357 ; ISSN :0020-1693 Kia, R ; Scholz, M ; Raithby, P. R ; Techert, S ; Sharif University of Technology
    2014
    Abstract
    Three new Cu(I) complexes containing bidentate N^N donor ligands with the general formula [Cu(N^N)2][PF6] (N^N = 2,3-diphenyl-6,7-di-p-tolyl-1,4,5,8-tetraazaphenanthrene (L1), 2,3-diphenyl-6,7-di(2-thienyl)-1,4,5,8-tetraazaphenanthrene (L2), and 2,3-diphenyl-6,7-di-p-fluorophenyl-1,4,5,8-tetraazaphenanthrene (L3), were prepared by the reaction of [Cu(CH3CN)4][PF6] with two equivalents of the N^N ligand. Single-crystal X-ray diffraction analysis confirmed that in each complex the metal displays a distorted tetrahedral geometry surrounded by the four N atoms of the two sterically hindered substituted tetraazaphenanthrene (TAP) ligands. Density functional theory (DFT) and time-dependent density... 

    Optimising operational cost of a smart energy hub, the reinforcement learning approach

    , Article International Journal of Parallel, Emergent and Distributed Systems ; 2014 ; ISSN: 17445760 Rayati, M ; Sheikhi, A ; Ranjbar, A. M ; Sharif University of Technology
    2014
    Abstract
    The concept of smart grid (SG) has been introduced to improve the operation of the power systems. In modern structures of power systems, different reasons prompt researchers to suggest integrated analysis of multi-carrier energy systems. Considering synergy effects of the couplings between different energy carriers and utilising intelligent technologies for monitoring and controlling of energy flow may change energy system management in the future. In this paper, we propose a new solution which is entitled ‘smart energy hub’ (SEH) that models a multi-carrier energy system in a SG. SEH solutions allow homeowners to manage their energy consumption to reduce their electricity and gas bill. We... 

    Mesoscopic analysis of online social networks: The role of negative ties

    , Article Physical Review E - Statistical, Nonlinear, and Soft Matter Physics ; Vol. 90, issue. 4 , 2014 ; SSN: 15393755 Esmailian, P ; Abtahi, S. E ; Jalili, M ; Sharif University of Technology
    2014
    Abstract
    A class of networks are those with both positive and negative links. In this manuscript, we studied the interplay between positive and negative ties on mesoscopic level of these networks, i.e., their community structure. A community is considered as a tightly interconnected group of actors; therefore, it does not borrow any assumption from balance theory and merely uses the well-known assumption in the community detection literature. We found that if one detects the communities based on only positive relations (by ignoring the negative ones), the majority of negative relations are already placed between the communities. In other words, negative ties do not have a major role in community... 

    Novel unbreakable solid-phase microextraction fibers on stainless steel wire and application for the determination of oxadiargyl in environmental and agricultural samples in combination with gas chromatography-mass spectrometry

    , Article Talanta ; Vol. 128, issue , 2014 , Pages 231-236 ; ISSN: 00399140 Es-Haghi, A ; Baghernejad, M ; Bagheri, H ; Sharif University of Technology
    2014
    Abstract
    Sol-gel based solid-phase microextraction fibers supported by a stainless steel wire were fabricated and employed for GC-MS determination of oxadiargyl in real samples. The fibers were based on four compounds with different polarity: polar and non-polar (end-capped) poly(dimethylsiloxane) (PDMS), polyethylene glycol (PEG), and poly(ethylene-propyleneglycol)-monobutyl ether (UCON). For this purpose, the surface of the stainless steel was initially modified by (3-mercaptopropyl) trimethoxysilane. The results of the modification procedure were evaluated by cyclic voltammetry and energy dispersive X-ray (EDX) spectroscopy. After the modification, four different sol-gel based SPME fibers with... 

    Preparation and characterization of nanostructured TiO2thin film codoped with nitrogen and vanadium on glass surface by sol–gel dip-coating method

    , Article Research on Chemical Intermediates ; 2014 ; ISSN: 09226168 Khatibnezhad, H ; Sani, M. A. F ; Sharif University of Technology
    2014
    Abstract
    To enhance hydrophilicity and photocatalytic activity, N-doped and N–V-codoped TiO2films were coated on glass substrates by the sol–gel dip-coating method. The substrates were previously coated with SiO2using the same method. The coated samples, after annealing at 450 °C for 30 min in air, were analyzed by an X-ray diffractometer, scanning electron microscope, Fourier transform infrared spectroscope, X-ray photoelectron spectroscope, and UV–visible spectroscope. The SiO2/N–V-codoped TiO2photocatalyst showed a narrower band gap (2.93 eV) compared to the SiO2/N-doped. Degradation tests, methyl orange under UV light and stearic acid under visible light, were performed in order to evaluate...