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A theoretical game approach for two- echelon stochastic inventory system
, Article Acta Polytechnica Hungarica ; Volume 12, Issue 4 , 2015 , Pages 221-239 ; 17858860 (ISSN) ; 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...
Exploring cognitive activation writing strategies among iranian english language teachers
, Article Language Related Research ; Volume 12, Issue 5 , 2021 , Pages 433-462 ; 23223081 (ISSN) ; 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...
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) ; 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...
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) ; 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
Exploring cognitive activation writing strategies among iranian english language teachers
, Article Language Related Research ; Volume 12, Issue 5 , 2021 , Pages 433-462 ; 23223081 (ISSN) ; 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...
Evaluation of marketing-pricing decisions in a two-echelon supply chain
, Article Engineering Economics ; Volume 24, Issue 2 , 2013 , Pages 135-143 ; 13922785 (ISSN) ; 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...
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) ; 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...
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) ; 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
Effect of short carbon fiber on thermal, mechanical and tribological behavior of phenolic-based brake friction materials
, Article Composites Part B: Engineering ; Volume 168 , 2019 , Pages 98-105 ; 13598368 (ISSN) ; Shojaei, A ; Arjmand, M ; Alaei, Y ; Yan, N ; Sharif University of Technology
Elsevier Ltd
2019
Abstract
The phenolic-based brake friction composites containing 0, 1, 2 and 4 vol% carbon fiber were fabricated in this study. Thermogravimetric analysis (TGA) revealed the adverse impact of carbon fiber on the thermal stability of the composites under air atmosphere. Differential scanning calorimetry (DSC) of the uncured samples indicated the positive impact of carbon fiber on the crosslink density of the phenolic resin. Viscoelastic results drawn from the dynamic-mechanical analysis (DMA) suggested that inclusion of carbon fiber increased the storage modulus and decreased the damping factor of the frictional composites. The tribological behavior of the specimens was assessed with a chase type...
A Game Theoretic Inventory Model for a Two-Echelon Supply Chain with Poisson Demand
, M.Sc. Thesis Sharif University of Technology ; 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) ; 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
Investigating the Behaviour of Some Kind of Fibre-reinforced Concrete
, M.Sc. Thesis Sharif University of Technology ; 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...
Human Genome Sequence Analysis Using Statistical and Machine Learning Methods
,
M.Sc. Thesis
Sharif University of Technology
;
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...
Study of Customers’ Motivations and the Impact of Touchpoints on Motives to Use Different Industries of the Sharing Economy
, M.Sc. Thesis Sharif University of Technology ; Talebian, Masoud (Supervisor) ; Aslani, Shirin (Supervisor)
Abstract
With the rise of the sharing economy, customers’ motivations to participate has become a controversial phenomenon. The sharing economy has different industries that might itself be a reason for the emergence of different incentives in customers. Moreover, these industries can affect motivation by controlling various touchpoints Two dimensions, quantity and quality illustrate the impact of touchpoints The encounter of touchpoints with both of the provider and consumer side might confuse companies to choose the best composition of has been conducted to identify the importance of motives to use different industries of the sharing economy and examine the impact of the brands’ touchpoints . In...
A Machine Learning Simulator for Task Offloading and Resource Allocation in IoV
, M.Sc. Thesis Sharif University of Technology ; Bayat Sarmadi, Siavash (Supervisor)
Abstract
Recent years have witnessed significant advancements in the smart transportation industry. Timely execution of processes and tasks prior to deadlines is crucial and sensitive. With the advancement of the automotive industry and smart transportation vehicles, the number of smart vehicles is increasing day by day. However, not all devices can perform their respective tasks on time, hence the need for edge network servers to assist in task execution .Decision-making regarding task execution methods and resource allocation in mobile networks poses a significant challenge. In recent research, given the complexity of the issue and the advancements in machine learning algorithms, the efficacy of...
Study on Structure, Mechanical Properties, and Flammability of PC/ABS
, M.Sc. Thesis Sharif University of Technology ; Bagheri, Reza (Supervisor) ; Seyed Reyhani, Morteza (Supervisor)
Abstract
Polycarbonate (PC) is known as one of the engineering plastics with remarkable mechanical properties, but the application of this polymer is limited due to its high notch sensitivity. Blending polycarbonate with other polymers such as acrylonitrile butadiene styrene (ABS) is a method to resolve this disadvantage. PC/ABS blends are commonly used in automotive industry, electrical and electronic devices. As PC and ABS are not completely miscible, a variety of compatibilizers are used to achieve a suitable microstructure and high engineering properties. Considering crucial applications of PC/ABS blends, different flame retardants are also used to reduce the flammability. These flame retardants...
Synthesis of Dithiocarbamate Derivatives and Their Applications to Prepare Heterocyclic Compounds
, M.Sc. Thesis Sharif University of Technology ; 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...
Probability of missed detection as a criterion for receiver placement in MIMO PCL
, Article IEEE National Radar Conference - Proceedings, 7 May 2012 through 11 May 2012, Atlanta, GA ; 2012 , Pages 0924-0927 ; 10975659 (ISSN) ; 9781467306584 (ISBN) ; Chitgarha, M. M ; Radmard, M ; Nayebi, M. M ; Sharif University of Technology
IEEE
2012
Abstract
Using multiple antennas at the transmit and receive sides of a passive radar brings both the benefits of MIMO radar and passive radar. However one of the obstacles arisen in such configuration is the receive antennas placement in proper positions so that the radar performance is improved. Here we just consider the case of positioning one receiver among multiple illuminators of opportunity. Indeed it is a start for the solution of optimizing the geometry of the multiple receivers in a passive radar
An efficient method for the ring opening of epoxides with aromatic amines by Sb(III) chloride under microwave irradiation
, Article Journal of Chemical Research ; Issue 4 , 2008 , Pages 220-221 ; 03082342 (ISSN) ; Hashemi, M. M ; Mottaghi, M. M ; Foroughi, M. M ; Sharif University of Technology
2008
Abstract
SbCl3 supported on montmorillonite K-10 is an efficient catalyst for the ring opening of epoxides with aromatic amines under solvent-free conditions and microwave irradiation to give the corresponding b-amino alcohols in high yields with high regioselectivity
MIMO radar signal design to improve the MIMO ambiguity function via maximizing its peak
, Article Signal Processing ; Volume 118 , 2016 , Pages 139-152 ; 01651684 (ISSN) ; Radmard, M ; Nazari Majd, M ; Karbasi, S. M ; Nayebi, M. M ; Sharif University of Technology
Elsevier
2016
Abstract
One of the important obstacles in MIMO (Multiple Input Multiple Output) radars is the issue of designing proper transmit signals. Indeed, the capability of signal design is a significant advantage in MIMO radars, through which, the system can achieve much better performance. Many different aspects of this performance improvement have been considered yet, and the transmit signals have been designed to attain such goal, e.g., getting higher SNR or better detector's performance at the receiver. However, an important tool for evaluating the radar's performance is its ambiguity function. In this paper, we consider the problem of transmit signal design, in order to optimize the ambiguity function...