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    A Hybrid Simulated Annealing Algorithm For Winner Determination problem In Combinatorial Auction

    , M.Sc. Thesis Sharif University of Technology Arab Momeni, Mojtaba (Author) ; Kianfar, Farhad (Supervisor)
    Abstract
    One of the most important issues that an organization faced with is resource management. The proper resource management has the great rule in organization cost reduction. One of the most efficient processes in resource allocation is auction and there is different auction with different mechanism and goals. In an auction there is a set of items and a set of bids, and the task of auctioneer is matching items with suitable bids. Each bid consist of desirable items and the bidder value of that items. In an auction process, after mechanism design of auction and auction implementation we must identify the winners of auction and this is a hard problem even in simple auction.
    In this study we... 

    Design and Dynamics Control of Six Degree of Freedom Microrobot

    , M.Sc. Thesis Sharif University of Technology Motekallem, Abolfazl (Author) ; Sayyaadi, Hassan (Supervisor)
    Abstract
    The field of microrobotics has seen tremendous advances in recent years. Potential high impact applications of untethered microrobots such as minimally invasive diagnosis and treatment inside the human body, biological studies or bioengineering, microfluidics, desktop micromanufacturing, and mobile sensor networks for environmental and health monitoring are reported. However, There are significant challenges in microrobotic technology, including energy resources, control systems, reliability and safety, design and manufacturing of micromotors and localization. In this work, overall size scale being micron scale is emphasized where mobile robots able to fit in spaces smaller than a millimeter... 

    Project Scheduling Subject to Nonrenewable Resource with Proscheduled Procurement

    , Ph.D. Dissertation Sharif University of Technology Shirzadeh Chaleshtari, Ali (Author) ; Shadrokh, Shahram (Supervisor)
    Abstract
    Among various types of resources defined in the project scheduling literature, the most studies have been conducted on the renewable and nonrenewable resource types. Definition of different resources in the project scheduling literature is based on the specification of the resources in the real projects. Yet there are some sort of nonrenewable resources in the real projects that are not exactly similar to the type defined in the project scheduling literature. The difference stems from this fact that in the project scheduling literature, it is supposed that the nonrenewable resources required for the execution of the project activities are available in full amount at the beginning of the... 

    A Heuristic Method for Solving VRP Problem with Customer Loyalty

    , M.Sc. Thesis Sharif University of Technology Rafiei Tabatabaei, Mohammad Javad (Author) ; Fazli, Mohammad Amin (Supervisor)
    Abstract
    This paper is concerned with the Vehicle Routing Problem (VRP) in a fleet with customer loyalty. In this work, we consider priority for customers according to their loyalty and try to declare an objective function which concerns customers' satisfaction along other normal VRP objectives like route optimization  

    Solving Location Problem for Vehicle Identification Sensors to Observe or Estimate Path Flows in Larg-Scale Networks

    , M.Sc. Thesis Sharif University of Technology Talebian Yazdi, Pegah (Author) ; Shafahi, Yousef (Supervisor)
    Abstract
    Origin-Destination (OD) demand is one of the important requirements in transportation planning. Estimating OD demand could be an expensive and time consuming procedure. These days using vehicle identification sensors for OD estimation has become very common because of its low cost and high accuracy. In this study, we focus on solving location problems of these sensors with the aim of observe and estimate path flows. These problems have only been solved for small-scale networks until recently due to being computationally expensive. These years two basic models have been introduced : one, without considering time of vehicle ID detection and one, with considering that information. In this... 

    Plastic Analysis of Two Dimensional Frames using Ant Colony Algorithms

    , M.Sc. Thesis Sharif University of Technology Pouraghajan, Marjan (Author) ; Jahanshahi, Mohsen (Supervisor)
    Abstract
    In previous decades, easy access to material and low cost human power allow the product process to be performed in a preferred way. The limit in amount of material, economy, and the efficiency of the model has not been influential like these days. Today, the effective use of material and consideration of an economic model have great importance. It is obvious that a process of designing implies optimizing which the range of its using is also continuing in many engineering sciences. Many optimization issues contain discrete nature. Many of searching spaces that we encounter in the real world applications are not necessarily continuous as a condition which has crucial importance for classic... 

    Optimizing a Flowshop Model with the Objective of Minimizing Total Weighted Tardiness while Considering due Dates on All Machines

    , M.Sc. Thesis Sharif University of Technology Nadimi, Fattane (Author) ; Ghassemi Tari, Farhad (Supervisor)
    Abstract
    Minimizing completion time of tasks in a flowshops has always attracted attention of researchers since it was introduced by Johnson, 1954. If all jobs are processed in the same order, the sequence is called a permutation sequence. Tardiness factor is one of important factors in permutation flowshop sequencing problem. Minimizing this factor brings about increase in service level of the shop and is helpful in meeting customer’s needs. Since, minimizing tardiness in PFSP in among NP-hard problems, computational efforts in this area has focused on heuristic approaches. However, the researches has always considered due dates only on the last machine. It means, always it has been assumed that due... 

    Evaluating the Benefit of Imperfection Advance Load Information in a Transportation Spot Market

    , M.Sc. Thesis Sharif University of Technology Mirbaygi Shahabad, Mohammad Jalal (Author) ; Shaderukh, Shahram (Supervisor) ; Najafi, Mehdi (Supervisor)
    Abstract
    This study examines how imperfect advance load information (IALI) can improve profits and vacancies for a trucking company. To evaluate the value of IALI, first, a deterministic mathematical model is created. Next, we propose a Markov decision programming approach that can use this IALI.Due to exponential size of the state space the problem cannot be solved to optimality it in polynomial time so we suggest a heuristic algorithm.After designing a comprehensive set of experiments, we use both models using a dynamic implementation mechanism to evaluate the benefits of using this information. Statistical analysis and literature show that, firstly, the use of IALI can significantly improve the... 

    Yield-driven design-time task scheduling techniques for multi-processor system on chips under process variation: A comparative study

    , Article IET Computers and Digital Techniques ; Volume 9, Issue 4 , 2015 , Pages 221-229 ; 17518601 (ISSN) Momtazpour, M ; Assare, O ; Rahmati, N ; Boroumand, A ; Barati, S ; Goudarzi, M ; Sharif University of Technology
    Institution of Engineering and Technology  2015
    Abstract
    Process variation has already emerged as a major concern in design of multi-processor system on chips (MPSoC). In recent years, there have been several attempts to bring variability awareness into the task scheduling process of embedded MPSoCs to improve performance yield. This study attempts to provide a comparative study of the current variation-aware design-time task and communication scheduling techniques that target embedded MPSoCs. To this end, the authors first use a sign-off variability modelling framework to accurately estimate the frequency distribution of MPSoC components. The task scheduling methods are then compared in terms of both the quality of the final solution and the... 

    Using flower pollinating with artificial bees (FPAB) technique to determine machinable volumes in process planning for prismatic parts

    , Article International Journal of Advanced Manufacturing Technology ; Volume 45, Issue 9-10 , 2009 , Pages 944-957 ; 02683768 (ISSN) Houshmand, M ; Imani, D. M ; Niaki, S. T. A ; Sharif University of Technology
    Abstract
    Process planning (PP) has an important role in manufacturing systems design and operations. Volume decomposition and machinable volumes (MVs) or machining features determination is the core activity in process planning. This process requires extraction of elementary volumes (EVs), merging or clustering EVs to construct feasible MVs and finally selecting an optimal combination of MVs. Development of MVs is an important activity, so that better solution is obtained by better developed MVs. Generation of limited number of MVs or machining features, which is often performed by experts may miss the optimal solution. Also, using exact methods such as combinatorial optimization not only generate... 

    Using a classifier pool in accuracy based tracking of recurring concepts in data stream classification

    , Article Evolving Systems ; Volume 4, Issue 1 , 2013 , Pages 43-60 ; 18686478 (ISSN) Hosseini, M. J ; Ahmadi, Z ; Beigy, H ; Sharif University of Technology
    2013
    Abstract
    Data streams have some unique properties which make them applicable in precise modeling of many real data mining applications. The most challenging property of data streams is the occurrence of "concept drift". Recurring concepts is a type of concept drift which can be seen in most of real world problems. Detecting recurring concepts makes it possible to exploit previous knowledge obtained in the learning process. This leads to quick adaptation of the learner whenever a concept reappears. In this paper, we propose a learning algorithm called Pool and Accuracy based Stream Classification with some variations, which takes the advantage of maintaining a pool of classifiers to track recurring... 

    Type-II fuzzy route choice modeling

    , Article Annual Conference of the North American Fuzzy Information Processing Society - NAFIPS, 12 July 2010 through 14 July 2010 ; July , 2010 ; 9781424478576 (ISBN) Shafahi, Y ; Zarinbal Masouleh, A ; Zarinbal Masouleh, M ; Sharif University of Technology
    2010
    Abstract
    Route choice modeling is one of the most important parts of traffic assignment problem. Recently, this model is used to describe the reactions of drivers to Traveler Information Systems in order to develop accurate Advanced Traffic Management and Information System (ATMIS). Therefore accurate model is necessary. In this paper we proposed a new model based on Type-II fuzzy logic to model route choice problem. This model can take account of the imprecision, uncertainties and vagueness lying in the dynamic choice process and makes more accurate modeling of drivers' behavior than deterministic, stochastic and Type-I fuzzy models. In our proposed model we consider average speed and cost... 

    TSRN: A tabu search-based routing protocol for named data networking

    , Article Wireless Personal Communications ; Volume 101, Issue 3 , 2018 , Pages 1411-1428 ; 09296212 (ISSN) Shariat, Z ; Movaghar, A ; Hosseinzadeh, M ; Sharif University of Technology
    Springer New York LLC  2018
    Abstract
    Information-centric network (ICN) has become a basic research topic with regard to the future architecture of the Internet. Storage and routing data is an important feature of ICN, as it improves network performance and content distribution. One of the challenges in this type of network is the routing problem. The objective of this paper is to propose a routing algorithm in the named data network. Owing to the impressive results presented by the enhanced heuristic methods, tabu search has been selected to develop the proposed algorithm. This work has been carried out in five major steps, Creating the initial solution, The mechanisms of generating a neighborhood, Evaluating the neighbor... 

    Tree optimization in overlay multicast based on location and bandwidth

    , Article ICCTD 2009 - 2009 International Conference on Computer Technology and Development, 13 November 2009 through 15 November 2009 ; Volume 2 , 2009 , Pages 46-49 ; 9780769538921 (ISBN) Bagheri, M ; Movaghar, A ; Sharif University of Technology
    Abstract
    One of the main parts of peer-to-peer multicast is the structure of overlay network. Most of the existing works utilize some common parameters for constructing overlay tree. These parameters are bandwidth and delay. The mismatch between current overlay structure and underlying network topology causes severe link stress and then leads to high end to end latency. According to these problems, we propose a new overlay construction algorithm called OLT in this paper that finds the location of peers and tries to connect peers that are as close as possible. OLT exploits a number of heuristic techniques to reach an optimized tree even in case of peer heterogeneity and high churn rate. Our... 

    Transmission constrained energy and reserve dispatch by harmony search algorithm

    , Article 2009 IEEE Power and Energy Society General Meeting, PES '09, 26 July 2009 through 30 July 2009, Calgary, AB ; 2009 ; 9781424442416 (ISBN) Afkousi Paqaleh, M ; Hosseini, S. H ; Sharif University of Technology
    IEEE  2009
    Abstract
    Spinning reserve (SR) is one of the most important ancillary services which are needed for satisfying reliability requirements, including the desired level of security in power systems. By definition, spinning reserve is the unloaded section of synchronized generation that is able to respond immediately to serve load. This paper proposes a hybrid DCOPF and harmony search (HS) optimization method as a novel heuristic approach to the joint dispatch of energy and reserve considering the bottling of reserve due to transmission limits. The effectiveness of the proposed method is examined by applying it to the IEEE 30-bus test system. The results obtained using the proposed method are presented... 

    Train timetabling on double track and multiple station capacity railway with useful upper and lower bounds

    , Article Scientia Iranica ; Volume 24, Issue 6 , 2017 , Pages 3324-3344 ; 10263098 (ISSN) Oroojlooy Jadid, A ; Eshghi, K ; Sharif University of Technology
    Abstract
    Train scheduling has been one of the significant issues in the railway industry in recent years since it has an important role in efficacy of railway infrastructure. In this paper, the timetabling problem of a multiple-tracked railway network is discussed. More specifically, a general model is presented here in which a set of operational and safety requirements is considered. The model handles the trains overtaking in stations and considers the stations' capacity. The objective function is to minimize the total travel time. Unfortunately, the problem is NP-hard, and real-sized problems cannot be solved in an acceptable amount of time. In order to reduce the processing time, we presented some... 

    Towards obtaining more information from gas chromatography-mass spectrometric data of essential oils: An overview of mean field independent component analysis

    , Article Journal of Chromatography A ; Volume 1217, Issue 29 , 2010 , Pages 4850-4861 ; 00219673 (ISSN) Jalali Heravi, M ; Parastar, H ; Sereshti, H ; Sharif University of Technology
    2010
    Abstract
    Mean field independent component analysis (MF-ICA) along with other chemometric techniques was proposed for obtaining more information from multi-component gas chromatographic-mass spectrometric (GC-MS) signals of essential oils (mandarin and lemon as examples). Using these techniques, some fundamental problems during the GC-MS analysis of essential oils such as varying baseline, presence of different types of noise and co-elution have been solved. The parameters affecting MF-ICA algorithm were screened using a 25 factorial design. The optimum conditions for MF-ICA algorithm were followed by deconvolution of complex GC-MS peak clusters. The number of independent components (ICs) (chemical... 

    Total flow time minimization in a flowshop sequence-dependent group scheduling problem

    , Article Computers and Operations Research ; Volume 37, Issue 1 , 2010 , Pages 199-212 ; 03050548 (ISSN) Salmasi, N ; Logendran, R ; Skandari, M. R ; Sharif University of Technology
    Abstract
    We have developed a mathematical programming model for minimizing total flow time of the flow shop sequence dependent group scheduling (FSDGS) problem, typically classified as Fm|fmls, Splk, prmu|∑Cj. As the problem is shown to be strongly NP-hard, a tabu search (TS) algorithm as well as a hybrid ant colony optimization (HACO) algorithm have been developed to heuristically solve the problem. A lower bounding (LB) method based on the Branch-and-Price algorithm is also developed to evaluate the quality of the metaheuristic algorithms. In order to compare the performance of metaheuristic algorithms, random test problems, ranging in size from small, medium, to large are created and solved by... 

    Time-varying acceleration coefficients IPSO for solving dynamic economic dispatch with non-smooth cost function

    , Article Energy Conversion and Management ; Volume 56 , 2012 , Pages 175-183 ; 01968904 (ISSN) Mohammadi Ivatloo, B ; Rabiee, A ; Ehsan, M ; Sharif University of Technology
    2012
    Abstract
    The objective of the dynamic economic dispatch (DED) problem is to schedule power generation for the online units for a given time horizon economically, satisfying various operational constraints. Due to the effect of valve-point effects and prohibited operating zones (POZs) in the generating units cost functions, DED problem is a highly non-linear and non-convex optimization problem. The DED problem even may be more complicated if transmission losses and ramp-rate constraints are taken into account. This paper presents a novel and heuristic algorithm to solve DED problem of generating units, by employing time varying acceleration coefficients iteration particle swarm optimization... 

    Three heuristic clustering methods for haplotype reconstruction problem with genotype information

    , Article Innovations'07: 4th International Conference on Innovations in Information Technology, IIT, Dubai, 18 November 2007 through 20 November 2007 ; 2007 , Pages 402-406 ; 9781424418411 (ISBN) Moeinzadeh, M. H ; Asgarian, E ; Najafi Ardabili, A ; Sharifian R, S ; Sheikhaei, M. S ; Mohammadzadeh, J ; Sharif University of Technology
    IEEE Computer Society  2007
    Abstract
    Most positions of the human genome are typically invariant (99%) and only some positions (1%) are commonly variant which are associated with complex genetic diseases. Haplotype reconstruction is to divide aligned SNP fragments, which is the most frequent form of difference to address genetic diseases, into two classes, and thus inferring a pair of haplotypes from them. Minimum error correction (MEC) is an important model for this problem but only effective when the error rate of the fragments is low. MEC/GI as an extension to MEC employs the related genotype information besides the SNP fragments and so results in a more accurate inference. The haplotyping problem, due to its NP-hardness, may...