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mahmoodi-azar--karwan
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Development of an Integrated Model of Electricity & Methanol Co Production Through Solar Energy and CO2 Capture
, M.Sc. Thesis Sharif University of Technology ; Saboohi, Yadollah (Supervisor)
Abstract
Emission of CO2 and its diffusion into atmosphere is associated with negative effects on the environmental such as Green House Gases effect. Various techniques of CO2 Capture in energy conversion and processing plant are investigated. A method of CO2 Capture could be based on utilization of solar energy for producing methanol. Basic design of such a system and feasibility analysis of developing that system has been considered on the subject of the present research work. Basic design and commercial feasibility of the system producing methanol through capturing CO2 from exhaust gases of a power plant and hydrogen produced by using solar energy have done such an integrated system. The main...
Price competition in duopoly supply chains with stochastic demand [electronic resource]
, Article Journal Of Manufacturing Systems ; 01/2014 ; Eshghi, Kourosh ; Sharif University of Technology
Abstract
In the literature, substantial researches have been carried out on supply chain coordination. The majority of these studies suggest a mechanism that enforces the supply chain members to follow the strategies that produce the equilibrium of an integrated supply chain. Moreover, most of researches do not consider the competition among supply chains
A latency-tolerant MAC protocol for underwater acoustic sensor networks
, Article ICCAS 2010 - International Conference on Control, Automation and Systems, 27 October 2010 through 30 October 2010, Gyeonggi-do ; 2010 , Pages 849-854 ; 9781424474530 (ISBN) ; Manzuri, M. T ; Sharif University of Technology
2010
Abstract
Wireless networks with the shared media require Medium Access Control (MAC) protocol that provides contention resolution mechanism. The design of MAC protocol in underwater sensor networks is a challenging issue because of limited energy source and high propagation delay. The most important goal of the MAC design for underwater sensor networks is to resolve data packet collision efficiently with respect to energy consumption. So, selection of MAC protocol is an important task because it has significant impact on the system efficiency. A suitable MAC protocol must consider some factors such as fairness, energy consumption, latency and throughput based on various applications. The bandwidth in...
Semi-empirical modelling of hydraulic conductivity of clayey soils exposed to deionized and saline environments
, Article Journal of Contaminant Hydrology ; Volume 249 , 2022 ; 01697722 (ISSN) ; Sadeghi, H ; Sharif University of Technology
Elsevier B.V
2022
Abstract
Clay liners are widely used as porous membrane barriers to control solute transport and to prevent the leakage of leachate both in horizontal and vertical flow scenarios, such as the isolated base and ramps of sanitary landfills. Despite the primary importance of saturated hydraulic conductivity in a reliable simulation of fluid flow through clay barriers, there is no model to predict hydraulic conductivity of clayey soils permeated with saline aqueous solutions because most of the current models were developed for pure water. Therefore, the main motivation behind this study is to derive semi-empirical models for simulating the hydraulic conductivity of clayey soils in the presence of...
Synthesis of Ni-Co-CNT nanocomposite and evaluation of its photocatalytic dye (Reactive red 120) degradation ability using response surface methodology
, Article Desalination and Water Treatment ; Volume 216 , 2021 , Pages 389-400 ; 19443994 (ISSN) ; Seifpanahi Shabani, K ; Mahmoodi, B ; Mahmoodi, N. M ; Khorasheh, F ; Baghalha, M ; Sharif University of Technology
Desalination Publications
2021
Abstract
Herein, NiO and Co2 O3, NiCo2 O4, and NiCo2 O4 /multi-walled carbon nanotubes nanocomposite were synthesized by the hydrothermal method and characterized by scanning electron micros-copy, energy dispersive spectroscopy, and X-ray diffraction. The photocatalytic activity of the synthesized materials was evaluated by Reactive Red 120 dye degradation. The photocatalytic activity of NiO and Co3 O4 was enhanced not only by the formation of NiCo2 O4, but also by its interaction with the functionalized multiwall carbon nanotubes support. The response surface methodology (RSM) was used to obtain the optimum parameters, including catalyst dosage, initial dye concen-tration, and pH on the dye...
An Improved Latency- Tolerant MAC Protocol for Underwater Acoustic Sensor Networks
, M.Sc. Thesis Sharif University of Technology ; Manzuri, Mohammad Taghi (Supervisor)
Abstract
Wireless networks with the shared media require Medium Access Control (MAC) protocol that provides contention resolution mechanism. The design of MAC protocol is a challenging issue because of limited energy source and high propagation delay in UnderWater Acoustic Sensor Networks (UWASNs). The most important goal of the MAC design for underwater sensor networks is to resolve data packet collision efficiently with respect to energy consumption. So, selection of MAC protocol is an important task because it has significant impact on the system efficiency. A suitable MAC protocol must consider some factors such as fairness, energy consumption, latency and throughput based on various...
L-sorbose production by gluconobacter oxydans using submerged fermentation in a bench scale fermenter
, Article Applied Food Biotechnology ; Volume 7, Issue 1 , 2020 , Pages 41-48 ; Alemzadeh, I ; Sharif University of Technology
National Nutrition and Food Technology Research Institute
2020
Abstract
Background and objective: L-Sorbose, as a precursor of ascorbic acid, can be biologically produced using Gluconobacter oxydans. The aim of this study was to optimize production of L-Sorbose by controlling concentration of the substrates and starter cultures. Material and methods: In this study, effects of three various fermentation parameters on the concentration of L-sorbose were assessed using fermenter (28°C, 1.4 vvm) and response surface methodology. These parameters included quantities of D-sorbitol (120-180 g lDw-1) (Deionized water) and yeast extract (6-18 g lDw-1) and inoculum/substrate ratios (5-10%). Results and conclusion: Results showed that the fitted model with high values of...
Robust-fuzzy model for supplier selection under uncertainty: an application to the automobile industry
, Article Scientia Iranica ; Volume 25, Issue 4 , 2018 , Pages 2297-2311 ; 10263098 (ISSN) ; Modarres, M ; Azar, A ; Sharif University of Technology
Sharif University of Technology
2018
Abstract
This paper proposes an innovative robust-fuzzy method for multi-objective, multi-period supplier selection problem under multiple uncertainties. This approach integrates robust optimization and fuzzy programming. Uncertain parameters are modeled as random variables that take value within a symmetrical interval. However, due to the complexity or ambiguity of some real world problems and especially the nature of some of the available input data, the length of interval is also highly uncertain. This ambiguity motivated us to present a new approach, which could be applicable to multiple uncertainties conditions. Thus, in our approach, the half-length of these intervals is also represented by...
A Study on the Impact of Extract of Green Coffee Beans as a Green Corrosion Inhibitor of Mild Steel in Simulated Concrete Pore Solution
, M.Sc. Thesis Sharif University of Technology ; Afshar, Abdollah (Supervisor)
Abstract
In this study, the effect of green coffee extract powder, as a green corrosion inhibitor of steel in a concrete simulation environment was investigated. In this study, the green coffee extract was obtained by the Maceration method and its performance was investigated by weight loss method, electrochemical methods including Polarization, Electrochemical Impedance Spectroscopy. Scanning Electron Microscopy images were also used to visualize the corroded areas. The results of the polarization test showed that 450 mg/lit of coffee extract powder at 25 °C has the corrosion inhibiting efficiency of about 82% and the corrosion rate of the bare sample reduced from 6 to 1.16 mpy. The dosage of 550...
, M.Sc. Thesis Sharif University of Technology ; Eshghi, Kourosh (Supervisor)
Abstract
In literature, substantial works have been done on supply chain coordination. The majority of these works looking for a mechanism that enforces the supply chain members to follow strategies that produce the equilibria of an integrated supply chain, and most of this literature ignores competition between supply chains. In this thesis, we consider two distinct supply chains which compete to each other on the price. We present a method to calculate the equilibria for three structural forms. In the first form, two supply chains are integrated and in the second form, one of the supply chains is integrated and the other one is decentralized. Finally in the third form, both supply chains are...
Evaluation and Simulation of Tunnel Mid-shaft Effects on the Natural and Normal Ventilation Performance in a Subway Tunnel
, M.Sc. Thesis Sharif University of Technology ; Farhanieh, Bijan (Supervisor)
Abstract
Necessity of a public transport network, environmental protection and a highly land cost in urban areas have increased the desire for underground transportation systems. On the other hand, ventilation system design should be done precisely specially for longer tunnels, large undergrounds spaces and crowded places. Rate of energy reduction for vent systems operation is dependent on their proper implementation. Tunnel design efficiently is influenced by ventilation system. The tunnel mid shaft is complementary part of the underground railway systems that is required for exchange air between the tunnel and the railway station with ambient fresh air. An important application of the tunnel mid...
Proposing a Control Method for Influenza Disease
, M.Sc. Thesis Sharif University of Technology ; Shahrokhi, Mohammad (Supervisor)
Abstract
Immediate control of pandemic influenza to avoid casualties and financial losses is an important issue. In this thesis, two types of controllers including optimal controller and adaptive generalized predictive controller based on linear input-output model, with vaccine, treatment and quarantine being controlling variables, have been used to control influenza. Each controlling methods were investigated for different states including single-input single-output and multi-input single-output. Single-input single-output and multi-input single-output models are identified as online and offline using least squares method. Since it is difficult to exactly identify the model parameters, especially at...
Investigating the Use of Gold Nanoparticle in Increasing Dose of Tumor and Reducing the Dose of Normal Tissue in Brachytherapy
, M.Sc. Thesis Sharif University of Technology ; Hosseini, Abolfazl (Supervisor)
Abstract
Over the past few decades, brachytherapy has been used as one of the leading methods in the treatment of a wide range of cancers, including breast cancer. Due to the high dose gradient of brachytherapy radiation sources, this method is used to treat such tumors that are grown at the vicinity of sensitive points or tissues of the body. Therefore, as irradiation get started by implanting radiation sources in the desired position, at the same time healthy tissue are also receiving the same dose as tumor tissues do Reducing healthy tissue dose along with increasing the dose of tumor tissue is one of the challenging topics that researchers are always looking for a solution. In the left breast...
Facile, Efficient and Low Cost Synthesis of N-(1H-imidazoline-2-yl)-1H-Benzimidazol-2-Amine and its Derivatives
, M.Sc. Thesis Sharif University of Technology ; Mahmoodi Hashemi, Mohammed (Supervisor)
Abstract
Benzimidazoles are a bioactive family of chemicals which had been subject of many studies because of their valuable properties, and has a long history of production in chemical industries. Investigation on their properties and reactions with goal of achieving to new derivatives have drawn attention of many research teams. Recently, 2- Imidazolineaminobenzimidazole had been synthesized by microwave-assisted reaction of 2-Aminobenzimidazole with 2-Methylsulfanylimidazoline hydrogen iodide. But because of difficulties aroused by use of microwave system and expensive chemicals, we decided to utilized reaction procedures which could be facile, inexpensive with capability of high reaction scales....
Sodium hypochlorite-Dowex 1X8-200: A convenient oxidizing reagant
, Article Iranian Journal of Chemistry and Chemical Engineering ; Volume 21, Issue 2 , 2002 , Pages 71-73 ; 10219986 (ISSN) ; Ahmadibeni, Y ; Sharif University of Technology
2002
Abstract
The polymer supported hypochlorite ion is a facile selective oxidizing agent for the oxidation of various alcohols to aldehydes and ketones. Similarly it successfully oxidizes various Hantzsch type 1,4 - dihydropyridines to corresponding pyridines
Development of a Covering Location Model in Congested Networks
, M.Sc. Thesis Sharif University of Technology ; Shavandi, Hassan (Supervisor)
Abstract
Plants, distribution centers, and other facilities generally function for years or decades, during which time the environment in which they operate may change substantially. Costs, demands, travel times, and other inputs to classical facility location models may be highly uncertain. So when making decisions of location considering the factors that may change is beneficial. In this thesis a version of covering location model under uncertainty in a congested system is proposed. The aim is to locate m facilities to maximize the captured customer utility, having in mind that there may be up to q facilities established in future; the only information at hand about the number of the new facilities...
Exploring of Hydrogen Bond Effect on Acidity Value for Multifunctional Alcohols in Gas Phase & Nonaqueous Solvent via DFT Method
, M.Sc. Thesis Sharif University of Technology ; Fattahi, Alireza (Supervisor)
Abstract
Hydrogen bond is a type of molecular bonds which occurs between hydrogen and a highly electronegative atom( usually F, N and O) and results to special properties. Polyols and multihydroxyl compounds are among substances which have special properties such as acidity due to the existence of hydrogen bond in their molecular structure. Acidity in these compounds is a result of having stable anions due to intramolecular hydrogen bands. The existence of an electronegative group in addition to hydroxyl groups leads to increase the acidity in these substances. In this project acidities of some polyols and multihydroxyl compounds were calculated in both gas phase and solution phase( DMSO,...
DuCNoC: a high-throughput FPGA-based NoC simulator using dual-clock lightweight router micro-architecture
, Article IEEE Transactions on Computers ; Volume 67, Issue 2 , February , 2018 , Pages 208-221 ; 00189340 (ISSN) ; Zamiri Azar, K ; Hessabi, S ; Sharif University of Technology
IEEE Computer Society
2018
Abstract
On-chip interconnections play an important role in multi/many-processor systems-on-chip (MPSoCs). In order to achieve efficient optimization, each specific application must utilize a specific architecture, and consequently a specific interconnection network. For design space exploration and finding the best NoC solution for each specific application, a fast and flexible NoC simulator is necessary, especially for large design spaces. In this paper, we present an FPGA-based NoC co-simulator, which is able to be configured via software. In our proposed NoC simulator, entitled DuCNoC, we implement a Dual-Clock router micro-architecture, which demonstrates 75x-350x speed-up against BOOKSIM....
Synthesis of Amines, Quinoxalines and New 1,4-Dihydropyridines in Water, Reactions of Indoles and Oxidation of 1,4-Dihydropyridines Using Sodium Nitrite
, Ph.D. Dissertation Sharif University of Technology ; Mahmoodi Hashemi, Mohammad (Supervisor)
Abstract
Briefly in this thesis, these subjects have been investigated: In recent years, water is used as a solvent instead of an organic solvents have become more and more important due to cheap and environmental consideration. In this context, preparation of quinoxaline, pyrrole, new 1,4-dihydropyridine and reduction of imine to amine with 1,4-dihydropyridine derivatives as the reducing agents with the use of one-pot multicomponent reaction have been reported. The existence of several hydrogen bonding groups (NH) in the new dihydropyridines they acts as biologically active compounds in the forthcoming years. In continuation, oxidation of thiols to disulfides in the presence of NBS and NCS and...
Static and Dynamic Modeling of Post Fixed Grooved Clay Brick System Behaviour for Wall and Surfaces Construction Without Mortar and With High Planarity
, M.Sc. Thesis Sharif University of Technology ; Esmaeil Pourestekanchi, Homayoon (Supervisor)
Abstract
Nowadays using traditional hollow clay brick in buildings to make walls and partitionsisvery common. Non-load-bearing walls in buildings are used as architectural elements for design purposes and protecting the people that are inside the building from cold , heat and sound pollution .Due to the new technologies and developing building codes interms of structure , non-load-bearing walls behaviour that is always neglected seems necessary to be considered. In this research we have investigated the static and dynamic behaviour of a patented non-load-bearing wall made up of a claybrick system with specially-designed-precision grooved faces that eliminates conventional cement mortar and results...