Search for: mashreghi--a
0.157 seconds

    Uranium Recovery from Liquid Waste of UCF by Solvent Extraction Method

    , M.Sc. Thesis Sharif University of Technology Aminoro-a-yaei Yamini, Leyla (Author) ; Samadfam, Mohammad (Supervisor) ; Taghizadeh, Mohammad (Supervisor) ; Ghasemi, Mohamad Reza (Co-Advisor)
    The Atomic Energy Organization of Iran (AEOI) has launched a program of low level waste management. This program also includes waste produced at Uranium Conversion Facility (UCF) of Esfahan. The liquid waste, which was generated during the operation of plant and concentrated in lagoon, was characterized for the development of the treatment process. The aim of this study was to recovery of uranium content of liquid waste in the lagoon. The recovery of uranium has the advantage of saving this valuable metal and the avoidance of unacceptable discarding solution to the environment. Uranium may be recovered from an aqueous solution by precipitation, solvent extraction and ion exchange.... 

    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)
    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... 

    Application of Multiscale methods for Modeling Spatial Heterogeneity in Complex Reservoirs

    , M.Sc. Thesis Sharif University of Technology Hajizadeh Mobaraki, Alireza (Author) ; Farhadpour, Farhad A (Supervisor) ; Sayf Kordi, Ali Akbar (Supervisor)
    Underground reservoirs are highly complicated due to the presence of spatial heterogeneities at length scales that span from micrometer in pore structure of the rocks to kilometer in the reservoir models. While large-scale flow units need to be characterized using seismic and well data, detailed displacements of fluids in pore space need to be modeled using thin section analysis and pore network modeling. It is therefore necessary to adopt a multi-scale approach to reservoir description to make best use of all the available data that vary over several orders of magnitude, from micro-scale in pore structure to field scale in reservoir flow models. In this thesis, an integrated framework for... 

    Biocracking of Heavy Fuel Oil (Mazut) By Native Microorganisms

    , M.Sc. Thesis Sharif University of Technology Chackoshian Khorasani, Alireza (Author) ; Yaghmaei, Soheila (Supervisor) ; Mashreghi, Mansour (Supervisor)
    Biocracking mazut by native capable microorganisms and practically modeling it is one of the new perfect fields of biotechnology in petroleum manufacture. Sampling soil and water sources polluted by petroleum compounds, has caused a new bacterial strain of Enterobacter cloacae (BBRC 10061) has been identified and isolated from soil in Mashhad contaminated by petroleum wastewater and mixture to biodegrade mazut. Using mixed culture isolated from the sources instead of BBRC 10061 makes same results. In aerobic condition, 13% of mazut in mineral medium has degraded for 10 days however amount of degraded mazut varies with process conditions. Study of fixing and floating mazut, application of... 

    Spectrophotometric Determination of Ametryn Herbicide in Drainage Water Based on Aggregation of Gold Nanoparticles Capped with Citrate

    , M.Sc. Thesis Sharif University of Technology Rastgar, Mortaza (Author) ; Hormozi-Nezhad, Mohammad Reza (Supervisor) ; Torkian, A (Supervisor)
    Due to vast use of Ametryn herbicide in agricultural and even non-agricultural activities and the possibility of contamination of carp and natural water sources by this herbicide, determination of this herbicide in surface and ground water sources is very important. Therefor introducing simple and sensitive method for determination of Ametryn is critical.
    This study demonstrate a simple and sensitive colorimetric method for the detection and determination of Ametryn based on aggregation of citrate capped AuNPs. Studied method relies upon shape and distance dependent AuNPs surface plasmon resonance. By replacing the sulfide containing Ametryn herbicide with citrate molecules on AuNPs... 

    Parameterized Approximation Algorithms for Bounded Diameter Minimum Steiner Tree Problem

    , M.Sc. Thesis Sharif University of Technology Mashreghi, Ali (Author) ; Zarei, Alireza (Supervisor)
    Given a graph G with a set of terminals, two weight functions c and d defined on the edge set of G, and a bound D, a popular NP-hard problem in designing networks is to find the minimum cost Steiner tree (under function c) in G, to connect all terminals in such a way that its diameter (under function d) is bounded by D. Marathe et al. [1] proposed an (O(log2n);O(log2n)) approximation algorithm for this bicriteria problem, where n is the number of terminals. The first factor reflects the approximation ratio on the diameter bound D, and the second factor indicates the cost-approximation ratio. Later, Kapoor and Sarwat [2] introduced a parameterized approximation algorithm with performance... 

    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)
    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  

    Trajectory Optimization of a Dual-arm Cam-lock Robot Considering Redundancy

    , M.Sc. Thesis Sharif University of Technology Rashidnejhad, Sajad (Author) ; Meghdari, A. (Ali) (Supervisor) ; Ghaemi Osgouie, Kambiz (Supervisor)
    In the present work, trajectory optimization of the Dual-Arm Cam-Lock robot considering kinematic and dynamic redundancy is performed. First, the optimal control problem is solved only considering kinematic redundancy and then is solved considering dynamic redundancy. General form of the dynamic model for the system is developed using Lagrangian relations. Global optimization method is used for redundancy resolution problem. A performance index is defined based on the consumed kinetic energy and is minimized through a desired trajectory using the global optimization method. Formulations of optimal control problem are derived and initial boundary problem is changed to two point boundary value... 

    Nonlinear Geometric Approach to Fault Detection in Mechanical Systems

    , M.Sc. Thesis Sharif University of Technology Mashreghi, Ali (Author) ; Namvar, Mehrzad (Supervisor)
    The demand for safety operating systems is growing with the new developments in technology. One of the important and critical issues in system monitoring is the capability of the system to detect probable faults and hazards. In model-based fault detection one specific diagnostic signal called residual should be generated for each fault that is only sensitive to a particular fault and independent of other faults and disturbances. In this thesis we try to investigate the nonlinear geometric approach in fault detection of a class of mechanical systems. After a brief introduction to geometric tool for nonlinear inputaffine systems and conditions in which output is decoupled from input, we... 

    Geometric-Based Fault Diagnosis in a Grid-Connected Inverter

    , Ph.D. Dissertation Sharif University of Technology Mashreghi, Ali (Author) ; Namvar, Mehrzad (Supervisor)
    Inverters are the main utility in transmitting power from distributed generation (DG) systems toward grid and their safe and immune performance has become a major concern among the system designers. In addition to poor power transmittance, faults in inverter can harm other equipment such as DG and local load. Consequently different protections has been considered to increase the reliability of these systems. Some of these protections like fuses and varistors are implemented in the hardware while others are considered in the processor. In the later class of protections, fault detection and isolation (FDI) system has been the subject of intense investigation in inverters over the past two... 

    Business ethics : a philosophical and behavioral approach

    , Book Conrad, Christian A.
    Springer International Publishing AG  2018

    Clinical methods in medical family therapy

    , Book ; Mendenhall, Tai ; Lamson, Angela ; Hodgson, Jennifer ; Baird, Macaran A
    Springer International Publishing AG  2018

    Energy and the wealth of nations : an introduction to biophysical economics

    , Book Hall, Charles A. S ; Klitgaard, Kent
    Springer International Publishing AG  2018

    Disability and vocational rehabilitation in rural settings : challenges to service delivery

    , Book ; Harley, Debra A ; Ysasi, Noel A ; Bishop, Malachy L ; Fleming, Allison R
    Springer International Publishing AG  2018

    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
    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... 

    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
    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... 

    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
    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... 

    Electromechanical resonators based on electrospun ZnO nanofibers

    , Article Journal of Micro/ Nanolithography, MEMS, and MOEMS ; Vol. 13,Issue. 4 , 2014 ; ISSN: 19325150 Fardindoost, S ; Mohammadi, S ; Zad, A. I ; Sarvari, R ; Shariatpanahi, S. P ; Sharif University of Technology
    We present fabrication, characterization, and experimental results describing electrical actuation and readout of the mechanical vibratory response of electrospun ZnO nanofibers. For a fiber with an approximate radius of 200 nm and a length of 70 ìm, a resonance frequency around 3.62 MHz with a quality factor (Q) of about 235 in air at ambient conditions is observed. It is shown that the measured frequency of the resonance is consistent with results from finite element simulations. Also, the measurements were performed in an enclosed chamber with controlled levels of ethanol vapor. The adsorption of ethanol causes a shift in the resonance frequency of the fibers, which can be related to the... 

    Patchwise joint sparse tracking with occlusion detection

    , Article IEEE Transactions on Image Processing ; Vol. 23, Issue. 10 , 2014 , Pages. 4496-4510 ; ISSN: 10577149 Zarezade, A ; Rabiee, H. R ; Soltani-Farani, A ; Khajenezhad, A ; Sharif University of Technology
    This paper presents a robust tracking approach to handle challenges such as occlusion and appearance change. Here, the target is partitioned into a number of patches. Then, the appearance of each patch is modeled using a dictionary composed of corresponding target patches in previous frames. In each frame, the target is found among a set of candidates generated by a particle filter, via a likelihood measure that is shown to be proportional to the sum of patch-reconstruction errors of each candidate. Since the target's appearance often changes slowly in a video sequence, it is assumed that the target in the current frame and the best candidates of a small number of previous frames, belong to... 

    Microstructure, mechanical properties, corrosion behavior and cytotoxicity of Mg-Zn-Al-Ca alloys as biodegradable materials

    , Article Journal of Alloys and Compounds ; Vol. 607 , 2014 , Pages 1-10 ; ISSN: 09258388 Homayun, B ; Afshar, A ; Sharif University of Technology
    Recently, considerable attentions have been paid to alloy Mg-4Zn-0.2Ca for biomedical applications due to its suitable biocompatibility and acceptable mechanical properties. In this work, the effects of the addition of different amounts of Al on microstructure, mechanical properties, degradation behavior, and biocompatibility of this alloy were investigated. The corrosion behaviors of the alloys were investigated through polarization tests, chronoamperometry analysis, immersion tests, and EIS experiments. The mechanical properties were analyzed by using tensile tests and compression tests. The results showed that the addition of Al up to 3 wt.% considerably modifies the degradation behaviors...