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    Synthesis of Dithiocarbamate Derivatives and Their Applications to Prepare Heterocyclic Compounds

    , M.Sc. Thesis Sharif University of Technology Alaei Tazehgheshlagh, Mohammad Ali (Author) ; Saeedi, Mohammad Reza (Supervisor)
    Abstract
    Sulfur containing compounds are known as the most applicable group of organic compounds. Due to their medicinal and biological applications, dithiocarbamates are the most considerable among the many sulfur containing compounds. There are many procedures reported to synthesize these compounds as synthetic intermediates instead of thiophosgen and isothiocyanates. The reaction of amine and carbon disulfide is reported as the best and least hazardous way to synthesize this functional group. In this project heterocyclic compounds such as thiazoles, thiazolidine-2-thione, and 2-(alkylthio)thiazol-4(5H)-one derivatives were synthesized from the reaction of prepared dithiocarbamates with in situ... 

    Human Genome Sequence Analysis Using Statistical and Machine Learning Methods

    , M.Sc. Thesis Sharif University of Technology Alaei, Shervin (Author) ; Manzuri Shalmani, Mohammad Taghi (Supervisor)
    Abstract
    During recent decades, dramatic advances in Genetics and Molecular Biology, has provided scientists with enormous amounts of molecular genomic information of different living organisms, from DNA sequences to complex 3d structures of proteins. This information is raw data which their analysis can provide better understanding of genome mechanisms, discriminating healthy and tumor cells, predicting disease type, making drugs based on genome information, and many more applications. Here, one important issue is the inevitable use of computer science and statistics to analyze these data; such that according to the vast amount of data, would provide intelligent methods, which yield most accurate... 

    A theoretical game approach for two- echelon stochastic inventory system

    , Article Acta Polytechnica Hungarica ; Volume 12, Issue 4 , 2015 , Pages 221-239 ; 17858860 (ISSN) Alaei, S ; Hajji, A ; Alaei, R ; Behravesh, M ; Sharif University of Technology
    Budapest Tech Polytechnical Institution  2015
    Abstract
    In this paper, we study the differences between the Centralized and Decentralized approaches in a two-echelon stochastic inventory system under the lost sale policy. We formulate the condition in which the retailer applies (r, Q) inventory policy, and his relation with the upper echelon who acts as a manufacturer. This situation has not been considered in the literature before. The Centralized approach results in optimal solution of the system and the Decentralized one is based on Stackelberg game in which the manufacturer is the leader. The demand arrives according to the stationary Poisson process. We drive the long-run average cost functions, then a set of computational steps are... 

    Dithiocarbamates as an efficient intermediate for the synthesis of 2-(alkylsulfanyl)thiazoles in water

    , Article Tetrahedron Letters ; Volume 57, Issue 8 , 2016 , Pages 883-886 ; 00404039 (ISSN) Ziyaei Halimehjani, A ; Hasani, L ; Ali Alaei, M ; Saidi, M.R ; Sharif University of Technology
    Elsevier Ltd  2016
    Abstract
    A simple, green and high-yielding procedure for the synthesis of 4-substituted-2-(alkylsulfanyl)thiazoles from the reaction of dithiocarbamates and α-halocarbonyl containing compounds in water is described. Also, a one-pot, two-step procedure for the synthesis of 2-(alkylsulfanyl)thiazoles from acetophenone and dithiocarbamates was developed. © 2016 Elsevier Ltd. All rights reserved  

    A Game Theoretic Inventory Model for a Two-Echelon Supply Chain with Poisson Demand

    , M.Sc. Thesis Sharif University of Technology Alaei, Saeed (Author) ; Hajji, Alireza (Supervisor)
    Abstract
    In this research, we study the differences between the centralized and decentralized approaches in a two-stage serial supply chain including a manufacturer and a retailer under the lost sale policy. The centralized approach results in optimal solution of the system and the decentralized one is based on Stackelberg game in which the manufacturer is the leader. The retailer uses the continuous review (r, Q) policy and the demand arrives according to the stationary Poisson process. In order to obtain the solution for two approaches, a set of computational steps are developed. Furthermore, we provide a numerical example and the corresponding sensitivity analysis to compare the two approaches.... 

    Fermi surface nesting and possibility of orbital ordering in FeO

    , Article Physics Letters, Section A: General, Atomic and Solid State Physics ; Volume 374, Issue 36 , August , 2010 , Pages 3793-3796 ; 03759601 (ISSN) Alaei, M ; Jafari, S. A ; Sharif University of Technology
    2010
    Abstract
    Remarkable inter-band nesting in FeO Fermi surface, hints to examine energy of orbitally ordered states, which turn out to be more stable. We propose this method as a general scheme to check for possibility of orbital ordering in first principle calculations, and demonstrate it for known examples, LiVO2 and LaMnO3  

    Modification of carbohydrate polymers via grafting in air. 1. Ceric-Induced synthesis of starch-g-polyacrylonitrile in presence and absence of oxygen [electronic resource]

    , Article Starch - Starke ; Volume 54, Issue 3-4, pages 140–147, April 2002 Pourjavadi, A. (Ali) ; Zohurian Mehr, Mohammad J
    Abstract
    Monomer grafting, a unique technique for polysaccharide modification, is always performed under inert (e.g., N2) atmosphere. This work is the first report related to evaluating the possibility and efficiency of the grafting of acrylonitrile (AN) onto starch in presence of oxygen. Thus, corn starch (in both granular and gelatinized states) as well as soluble starch were grafted by AN using a ceric-carbohydrate redox initiating system. Graft copolymerizations were performed under nitrogen, air, and oxygen atmospheres at similar conditions. Grafting occurrence was verified using chemical and spectral proofs. The polymerization mechanism and kinetics were investigated by recording the... 

    Modification of carbohydrate polymers via grafting in Air. 2. Ceric-Initiated graft copolymerization of acrylonitrile onto natural and modified polysaccharides [electronic resource]

    , Article Starch - Stärke ; Volume 54, Issue 10, pages 482–488, October 2002 Pourjavad, A. (Ali) ; Zohuriaan-Mehr, Mohammad J
    Abstract
    Acrylonitrile (AN) was grafted onto various natural and modified polysaccharides (i.e., gum arabic, gum tragacanth, xanthan gum, sodium alginate, chitosan, sodium carboxymethyl cellulose, hydroxyethyl cellulose, methyl cellulose) by using ceric-carbohydrate redox initiating system. After overcoming practical problems, mainly from the high viscosity of the aqueous solutions of the different substrates, the graft copolymerization reactions were run either in air or in N2 atmosphere under similar conditions. Grafting was confirmed using chemical and spectral (FTIR) proofs. The reactions were kinetically investigated using semi-empirical expressions and time-temperature profiles. An anomalous... 

    Modeling of in Plane Behavior of Retrofitted Adobe Walls with Finite Element Method under Cyclic Loading

    , M.Sc. Thesis Sharif University of Technology Mohammad Panah, Hossein (Author) ; Bakhshi, Ali (Supervisor) ; Ghannad, Mohammad Ali (Co-Advisor)
    Abstract
    Statistical studies indicate the fact that in Iran, like many other developing countries, a significant percentage of buildings are made of traditional materials and most of them are adobe buildings especially in rural areas. Furthermore, geological data indicates that Iran is located in alps-Himalayas seismic zone and exposed by destructive earthquakes and adobe buildings suffer the most damages comparing with other type of the structures. According to these explanations, this research deals with adobe buildings behavior and provides solutions for reinforcing them and improving the seismic response of these buildings. These studies include numerical modeling with finite elements methods by... 

    Silica chloride/wet SiO2 as a novel heterogeneous system for the deprotection of acetals under mild conditions [electronic resource]

    , Article Phosphorus, Sulfur, and Silicon and the Related Elements ; Volume 178:2667-2670, Issue 12, 2003 Mirjalili, B. F. (BiBi Fatemeh) ; Pourjavadi, Ali ; Zolfigol, Mohammad Ali ; Bamoniri, Abdolhamid
    Abstract
    A combination of silica chloride and wet SiO2 was used as an effective deacetalizating agent for the conversion of acetals to their corresponding carbonyl derivatives under mild and heterogeneous condition  

    Evaluation of marketing-pricing decisions in a two-echelon supply chain

    , Article Engineering Economics ; Volume 24, Issue 2 , 2013 , Pages 135-143 ; 13922785 (ISSN) Alaei, S ; Behravesh, M ; Karegar, N ; Sharif University of Technology
    Kauno Technologijos Universitetas  2013
    Abstract
    This paper discusses the interaction between one manufacturer and a single retailer in a channel in which both are willing to optimize their profit by adjusting pricing and advertising decisions. The manufacturer produces and sells a product at wholesale price to the retailer who in turn distributes it to consumers with retail price. The market demand is simultaneously affected by retail price, brand advertising of the manufacturer, and local advertising of the retailer. A Cobb-Douglas demand function is used to demonstrate the relationship between the parameters. Decision variables are two firms’ prices and their advertising investments. The problem is modelled under integrated policy and... 

    Skiptree: a new scalable distributed data structure on multidimensional data supporting range-queries

    , Article Computer Communications ; Volume 33, Issue 1 , 2010 , Pages 73-82 ; 01403664 (ISSN) Alaei, S ; Ghodsi, M ; Toossi, M ; Sharif University of Technology
    2010
    Abstract
    This paper presents a new balanced, distributed data structure for storing data with multidimensional keys in a peer-to-peer network. It supports range queries as well as single point queries which are routed in O (log n) hops. Our structure, called SkipTree, is fully decentralized with each node being connected to O (log n) other nodes. We propose modifications to the structures, so that the memory usage for maintaining the link structure at each node is reduced from the worst case of O (n) to O (log n log log n) on the average and O (log2 n) in the worst case. It is also shown that the load balancing is guaranteed to be within a constant factor. Our experimental results verify our... 

    The relative importance of the business model motive for customer participation in the sharing economy

    , Article Sustainable Production and Consumption ; Volume 34 , 2022 , Pages 190-201 ; 23525509 (ISSN) Alaei, S ; Aslani, S ; Talebian, M ; Sharif University of Technology
    Elsevier B.V  2022
    Abstract
    The sharing economy, defined by peer-to-peer interactions through a platform, has been gaining ground in recent years. In this study, we discuss the relative importance of customers' perceived motives to participate in the two most common models of the sharing economy: access-based consumption and ownership-transfer. We focus on taxi-hailing and post-delivery as examples of access-based consumption and second-hand trade as an example of the ownership-transfer. While these two contain heterogeneous business model patterns that can motivate customers differently, common motives are significant in both models. We study common motives and motives aligned with the business model patterns, which... 

    SkipTree: A Scalable range-queryable distributed data structure for multidimensional data

    , Article 16th International Symposium on Algorithms and Computation, ISAAC 2005, Hainan, 19 December 2005 through 21 December 2005 ; Volume 3827 LNCS , 2005 , Pages 298-307 ; 03029743 (ISSN); 3540309357 (ISBN); 9783540309352 (ISBN) Alaei, S ; Toossi, M ; Ghodsi, M ; Sharif University of Technology
    2005
    Abstract
    This paper presents the SkipTree, a new balanced, distributed data structure for storing data with multidimensional keys in a peer-to-peer network. The SkipTree supports range queries as well as single point queries which are routed in O(log n) hops. SkipTree is fully decentralized with each node being connected to O(logn) other nodes. The memory usage for maintaining the links at each node is O(log n log log n) on average and O(log2 n) in the worst case. Load balance is also guaranteed to be within a constant factor. © Springer-Verlag Berlin Heidelberg 2005  

    Investigating the Behaviour of Some Kind of Fibre-reinforced Concrete

    , M.Sc. Thesis Sharif University of Technology Alaei Mahabadi, Alireza (Author) ; Khonsari, Vahid (Supervisor)
    Abstract
    While there are many advantages associated with concrete, including high compressive strength, durability and so forth, on the contrary, it has several disadvantages which may make engineers somewhat reluctant to use it. These include low tensile strength, high brittleness, low resistance to impact, large dimensions of structural cross sections, etc. In recent years, there have been many attempts to surmount these disadvantages by various means such as adding pozzolans, using FRPs, fibres, etc. In this project, the effects of using a special type of high strength steel fibre is studied. In order to investigate the effect of this fibre on the compressive behavior of concrete, 30 cylindrical... 

    Exploring cognitive activation writing strategies among iranian english language teachers

    , Article Language Related Research ; Volume 12, Issue 5 , 2021 , Pages 433-462 ; 23223081 (ISSN) Alaei, M. M ; Hassanzadeh, M ; Masoudi, M ; Sharif University of Technology
    Tarbiat Modares University  2021
    Abstract
    In order to engage students in higher-level thinking, cognitive activation (CA) strategies have been advanced and utilized in mathematics. CA develops when learners are challenged, confronted with conflicts, asked to think and explain clearly on their learning, and realize connections between new and previous content. Extending the theme to English language teaching (ELT), this study investigated Iranian English language teachers‟ knowledge and practice of cognitive activation writing strategies (CAWS). In so doing, a model was proposed based on a questionnaire that was developed and validated in the present study. Through this scale, knowledge and practice of CAWS by 213 English as a... 

    Exploring cognitive activation writing strategies among iranian english language teachers

    , Article Language Related Research ; Volume 12, Issue 5 , 2021 , Pages 433-462 ; 23223081 (ISSN) Mostafaei Alaei, M ; Hassanzadeh, M ; Masoudi, M ; Sharif University of Technology
    Tarbiat Modares University  2021
    Abstract
    In order to engage students in higher-level thinking, cognitive activation (CA) strategies have been advanced and utilized in mathematics. CA develops when learners are challenged, confronted with conflicts, asked to think and explain clearly on their learning, and realize connections between new and previous content. Extending the theme to English language teaching (ELT), this study investigated Iranian English language teachers‟ knowledge and practice of cognitive activation writing strategies (CAWS). In so doing, a model was proposed based on a questionnaire that was developed and validated in the present study. Through this scale, knowledge and practice of CAWS by 213 English as a... 

    Distributed Fault-tolerant Computation for Massive Data

    , M.Sc. Thesis Sharif University of Technology Mahvari Habibabadi, Mohammad Mahdi (Author) ; Maddah-Ali, Mohammad Ali (Supervisor)
    Abstract
    In this thesis we consider the problem of distributed computation by many processors.We mainly concentrate on matrix multiplication problem in this thesis because of its importance. A distributed system consists of N worker processors and one master processor. The master processor should distribute the computation between workers and after computation in each of them, collect the results. In this thesis, we are going to mitigate the effect of straggler processors by using coding methods. Straggler processors can cause delays in the computation time.In this thesis, we firstly introduce a method to multiply any number of matrices in each other. The proposed method occurred in one shot without... 

    Incomplete Reduction of Iron Ore in a Fluidized Bed Reactor

    , M.Sc. Thesis Sharif University of Technology Agha Ali, Mohammad Hadi (Author) ; Halali, Mohammad (Supervisor)
    Abstract
    The main goal of current investigation was partial reduction of Fe2O3 available in Hematite-rich ore to Magnetite by Fludization Bed method. The reductive gas, CO, was produced by incomplete combustion of Acetylene and Airmixed in inappropriate ratio. X-Ray Diffraction and X-Ray Florescence analyses were implemented in order to conducting qualitative analysis of present phases before and after reduction of the ore. Quantitative analysis of the same phases was also conducted by Titration. The latter analysis revealed the precise magnitude of available iron in each of the oxide containing phases. The chemical composition of the reactor gas was also determined before and after reduction... 

    Sequential Competitive Facility Location In Continuous Geometric Space

    , M.Sc. Thesis Sharif University of Technology Lavasani, Ali Mohammad (Author) ; Abam, Mohammad Ali (Supervisor)
    Abstract
    Abstract The problem of competetive facility location can be defined as follows: There are a number of customers in the form of points in space, and two players arrange a number of facilities in the form of points in space, given some limitations, respectively. Each customer’s connection to each facility has a cost for the customer and an advantage for the facility, and each customer wants to be connected to at most one of the facilities which has the lowest cost for him. The goal is to find the strategy of placing the facilities and determining the cost which the facility receives from the customer, in such a way that the player’s profit is maximised.In this thesis, we first sought to...