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    Unfolding of the Gamma-Ray Spectrum of the Scintillator Detectors Using the Neural Network Method

    , M.Sc. Thesis Sharif University of Technology Pezeshki, Ali (Author) ; Vosoughi, Naser (Supervisor)
    Abstract
    The analysis of gamma-ray spectra of low resolution detectors is difficult and sometimes impossible, as a result of photo peak’s overlapping. The usual methods of radiation spectra analysis based on fitting of peaks to mathematical curves or detecting of peaks with numerical calculation, are valid for high resolution detectors. However these methods are less successful for lower resolution detectors such as the common scintillators. The wide peaks in the spectrum maybe overlap and make it difficult to analysis. To solve this problem, we test here a method, based on the use of the artificial neural network. At first spectra of elements are converted to the patterns which are suitable for the... 

    An Abstract Model for Perso-Arabic Typography

    , M.Sc. Thesis Sharif University of Technology Esfahbod, Behnam (Author) ; Tabesh, Yahya (Supervisor)
    Abstract
    In this research, we provide an abstract model for the typography of Persian language (Perso-Arabic script) and study two text corpora based on the Unicode properties of characters and this model. Then we search the corpora for phrases with special properties, based on the abstract model  

    Simultaneous coordination of capacity building and price decisions in a decentralized supply chain

    , Article International Journal of Advanced Manufacturing Technology ; Volume 64, Issue 5-8 , 2013 , Pages 961-976 ; 02683768 (ISSN) Pezeshki, Y ; Baboli, A ; Akbari Jokar, M. R ; Sharif University of Technology
    2013
    Abstract
    In this paper, we investigate the simultaneous coordination of price and capacity building decisions in a dyadic supply chain. This problem is a combination of capacity reservation problem and pricing problem. While the coordination of supply chain with stochastic demand and fixed prices has received much attention in the literature, price-dependent and stochastic demand has been less considered. We study the latter case where a price-setting retailer faces a linear decreasing demand with respect to price. To capture the uncertainty of the demand, we add a stochastic variable to the demand function. In addition, we incorporate production rate and inventory cost on the supplier side. We... 

    Coordination by contract for capacity and price decisions considering stochastic and price-dependent demand settings

    , Article 41st International Conference on Computers and Industrial Engineering 2011, 23 October 2011 through 25 October 2011 ; 2011 , Pages 323-329 ; 9781627486835 (ISBN) Pezeshki, Y ; Baboli, A ; Jokar, M. R. A ; Sharif University of Technology
    2011
    Abstract
    In this paper, we investigate the simultaneous coordination of price and capacity building decision in a dyadic supply chain which is in the context of capacity reservation problem. While the coordination in this context with stochastic demand and fixed price has been received much attention in the literature, but the price-dependent and stochastic demand has been less considered. There is a price-setting buyer which faces a linear decreasing demand with respect to price. To capture the uncertainty nature of the demand we add a stochastic variable to the demand function. In addition, we incorporate production time and inventory cost in supplier side. We study the model in both additive and... 

    Coordination Mechanisms in Supply Chain by Contracts

    , Ph.D. Dissertation Sharif University of Technology Pezeshki, Yahya (Author) ; Akbari Jokar, Mohammad Reza (Supervisor)
    Abstract
    In decentralized Supply Chains, each member decides based on his own interests. Conflict of interests results in suboptimal decisions and poor performance for entire supply chains, as well seriously harms credibly information sharing across them. In this thesis, coordination of decisions in supply chains in the context of Capacity Procurement problem are studied in different situations in form of three models. In first model, a dyadic supply chain with stochastic demand and exogenous price is investigated by taking various costs into account. PARD and RCRS contracts are designed and proposed in order for coordination of decisions respectively in full and partial information updating... 

    A Novel Magnetic Molecularly Imprinted Polymers Nanoparticle as Extracting Medium For Micro-Solid Phase Extraction

    , M.Sc. Thesis Sharif University of Technology Yahya Baktash, Mohammad (Author) ; Bagheri, Habib (Supervisor)
    Abstract
    This thesis cantain two section. In the first section a novel extracting medium based on magnetic molecularly imprinted polymers (MIPs) nanoparticles was synthesized by chemical polymerization for micro-solid phase extraction. In this work, the modified chitosan magnetite nanoparticles (MNP-CS) was synthesized by co-precipitating Fe2+ and Fe3+ in the chitosan solution [1,2]. The characteristic properties of Fe3O4@MIPs nanoparticles were determined using Fourier transform infrared spectrometer. Extraction efficiency of the novel extracting medium was compared with MNP-CS sorbents for the determination of RhB in aqueous samples, via quantification by spectrofluorimetry. The obtained results... 

    Assessing Liquefaction Potential Based on Cone Penetration Test Results

    , M.Sc. Thesis Sharif University of Technology Pezeshki Najafabadi, Ali (Author) ; Ahmadi, Mohammad Mehdi (Supervisor)
    Abstract
    This study aimed to model the cone penetration test using FLAC 2D software in order to investigate the silty soils that can be found in tailing dams. Additionally, the model of the direct simple shear test was built in the software to estimate the variation of liquefaction potential in these soils with in-situ conditions. It should be noted that the constitutive law used in this study was the NORSAND model which meets the requirements of modeling in both tests. After validating the models, several important parameters are considered as variables to examine their effects on the results of both experiments. Regarding the validation of the models, the constructed numerical models of the cone... 

    Coordination mechanism for capacity reservation by considering production time, production rate and order quantity

    , Article Applied Mathematical Modelling ; Volume 37, Issue 20-21 , 2013 , Pages 8796-8812 ; 0307904X (ISSN) Pezeshki, Y ; Akbari Jokar, M. R ; Baboli, A ; Campagne, J. P ; Sharif University of Technology
    2013
    Abstract
    In this paper we study the coordination of a dyadic supply chain producing a high-tech product by contracts. The product has a short life cycle and the buyer faces stochastic demands during the selling period. We consider the production time, which causes the inventory costs on supplier's side. As the supplier builds production capacity in advance, the production rate is limited to the capacity created during the production time. In addition, we take into account the inventory cost and operational cost for the buyer. We examine the model under both full information and partial information updating situations, and propose a coordinating contract for each case. Our analysis includes the study... 

    A rewarding-punishing coordination mechanism based on Trust in a divergent supply chain

    , Article European Journal of Operational Research ; Volume 230, Issue 3 , 2013 , Pages 527-538 ; 03772217 (ISSN) Pezeshki, Y ; Baboli, A ; Cheikhrouhou, N ; Modarres, M ; Akbari Jokar, M. R ; Sharif University of Technology
    2013
    Abstract
    Coordination of decentralized supply chains using contract design is a problem that has been widely addressed in the literature. We consider a divergent supply chain including a supplier and several retailers producing fashion products with short sale seasons. The retailers cooperate with the supplier as sales agents; i.e.; they work in the framework of revenue sharing contracts. Because of their proximity to the market, retailers can provide more accurate demand forecasts to the supplier that is used to decide on issues such as capacity building and market prices with regard to retailers stiff due dates, different lead times and different price-dependent demand functions. To ensure abundant... 

    Study and Preparation of Paper Filter for Air Treatment in Internal Combustion Process

    , M.Sc. Thesis Sharif University of Technology Zare Shervedani, Ali (Author) ; Musavi, Abbas (Supervisor) ; Hamzeh, Yahya (Supervisor)
    Abstract
    Air filter paper is a combination of cellulosic, polymeric and resin materials with a certain permeability to air, which is used to prevent dust from entering the internal combustion process.The purpose of this research was to study and make air filter paper, based on which 4 samples of automobile air filter paper were produced. Samples with a combination of 2 types of cellulose fibers, imported short Kraft fibers and long Bangladeshi Kenaf fibers (skin) and one type of polymer fibers, Polyester fibers with a type of self-networking water-based Acrylic resin with glass conversion temperature (Tg) About 33 degrees Celsius and in the range of 20% by weight with a mass of about 120 g/m2 were... 

    Trust-based coordination mechanism in a divergent supply Chain

    , Article 62nd IIE Annual Conference and Expo 2012, 19 May 2012 through 23 May 2012 ; May , 2012 , Pages 3268-3277 Pezeshki, Y ; Baboli, A ; Cheikhrouhou, N ; Modarres, M ; Jokar, M. R. A ; Campagne, J. P ; Sharif University of Technology
    Institute of Industrial Engineers  2012
    Abstract
    We consider coordination by contract in a divergent supply chain including one manufacturer and several retailers which produces fashion products with short sale seasons. The retailers cooperate with the manufacturer as sales agents; i.e., they work in the framework of revenue sharing contracts. Because of their proximity to the market, retailers can provide more accurate demand forecast for the manufacturer when he wants to decide on his capacity building (expansion), product assignment decision and market prices with regard to retailers stiff due date, different lead times and different price-dependent demand functions. To ensure abundant supply and increase their sales, the retailers have... 

    Synergistic Wound Healing by Novel Ag@ZIF-8 Nanostructures

    , Article International Journal of Pharmaceutics ; Volume 629 , 2022 ; 03785173 (ISSN) Barjasteh, M ; Mohsen Dehnavi, S ; Ahmadi Seyedkhani, S ; Yahya Rahnamaee, S ; Golizadeh, M ; Sharif University of Technology
    Elsevier B.V  2022
    Abstract
    In this paper, novel zeolitic imidazolate framework-8 (ZIF-8) functionalized with Ag (Ag@ZIF-8) nanoparticles were synthesized through a green, facile and environmental-friendly process for wound dressing applications. X-ray diffraction revealed that the ZIF-8 and Ag@ZIF-8 were successfully synthesized by green solvents at ambient temperature. Field-emission scanning electron microscopy indicated a homogeneous porous blend of ∼30 nm chitosan/bacterial cellulose (CS/BC) nanofibers embedded with ∼80–110 nm nanoparticles of the ZIF-8 and Ag@ZIF-8. Transmission electron microscopy revealed the Ag@ZIF-8 nanostructures consist of ZIF-8 cores that are covered by 5–20 nm Ag nanoparticles. MTT assay... 

    Synthesis and Evaluation of A Catalyst for Selective Oxidation of H2S to Elemental Sulfur as A Desulfurization Method for Gaseous Streams

    , M.Sc. Thesis Sharif University of Technology Alemi, Faezeh (Author) ; Hamzehlouyan, Tayebeh (Supervisor) ; Rashidi, Alimorad (Supervisor) ; Zamani, Yahya (Supervisor)
    Abstract
    The selective oxidation of H2S into elemental sulfur is a complementary desulfurization method for reducing H2S emissions from gas streams. Several studies have been conducted in recent years to develop active, selective, and stable catalysts. The purpose of this research is to develop a catalyst with high activity and selectivity that is suitable for the gas output of one of the country's refineries. For this purpose, three supports of mixed metal oxide (solid solution), Ce-Al, Ce-Si, and Ce-Zr with a molar ratio of 1:2 (ceria: metal) were made by the co-precipitation method. In the following, three samples named 10V-CeAl, 10V-CeSi, and 10V-CeZr were prepared by impregnating 10% wt vanadium... 

    A new approach for simultaneously improved osseointegration and antibacterial activity by electrochemical deposition of graphene nanolayers over titania nanotubes

    , Article Applied Surface Science ; Volume 580 , 2022 ; 01694332 (ISSN) Yahya Rahnamaee, S ; Bagheri, R ; Vossoughi, M ; khafaji, M ; Asadian, E ; Ahmadi Seyedkhani, S ; Samadikuchaksaraei, A ; Sharif University of Technology
    Elsevier B.V  2022
    Abstract
    Simultaneous enhancement of osseointegration and bacterial infection prohibition through surface modifications is a challenging but promising approach to achieve durable implantation. To that end, we present a multifunctional surface coating composed of graphene nanolayers and hierarchical well-aligned TiO2 nanotubes with a nanoporous top layer (cRTNT). FESEM studies reveal tunable increasing island morphologies of graphene nanolayers (G) on cRTNT by a cyclic voltammetry process. XPS analysis shows that the enhanced interface chemistry is due to TiO2-carbon bonding. The roughness of the sample containing a medium amount of graphene, cRTNT-75%GO, was calculated ∼289 nm, which was 543% higher... 

    Manufacturing and Evaluation of Carbon Dioxide Hydrogenation Reaction Catalyst for Methanol Production

    , M.Sc. Thesis Sharif University of Technology Esmaeili, Mohammad (Author) ; Fotovat, Farzam (Supervisor) ; Zamaniyan, Akbar (Supervisor) ; Zamani, Yahya (Co-Supervisor) ; Rashidzadeh, Mehdi (Co-Supervisor)
    Abstract
    The hydrogenation of carbon dioxide to methanol represents a promising route for the efficient use of an anthropogenic greenhouse gas, in which catalysts play a key role in carbon dioxide conversion and methanol selectivity. In this study, firstly, CuO-ZnO-Al2O3, CuO-ZnO-ZrO2, CuO-ZnO-ZrO2-Al2O3, CuO-ZnO-Al2O3-CeO2 and CuO-ZnO-ZrO2-CeO2 catalysts were made using co-precipitation method, then these catalysts were characterized by inductively coupled plasma optical emission spectrometry, specific surface area and pore size distribution, X-ray diffraction, Field Emission Scanning Electron Microscopy, temperature programmed reduction. Finally, in order to compare the performance of the catalysts...