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    A Two Criteria Objective Function Flexible Flowshop Scheduling Problem With Machine Eligibility Constraint

    , M.Sc. Thesis Sharif University of Technology Tadayon, Bita (Author) ; Salmasi, Nasser (Supervisor)
    Abstract
    This study strives to minimize a two-criterion objective function of a flexible flow shop scheduling problem with receipt and delivery of jobs in groups and processing them individually. Every group of jobs has a release time, which means that all jobs are not available at the beginning of the planning horizon. Moreover, due to the special characteristics of every job in a group, only a subset of machines at each stage are eligible to process that job. This problem has many applications in production and service industries, such as restaurants and ceramic tile manufacturing companies. The objective function is determined based on the practical applications of the problem. It deals with... 

    Minimizing the Number of Tardy Jobs in Flow Shop Sequence Dependent Setup Times Scheduling Problem

    , M.Sc. Thesis Sharif University of Technology Varmazyar, Mohsen (Author) ; Salmasi, Nasser (Supervisor)
    Abstract
    This research investigates permutation flow shop scheduling problems with sequence-dependent setup times with minimizing the number of tardy jobs as criterion (Fm|prmu, Sijk|ΣUj). A mixed integer linear programming model has been developed for the research problem. As the problem is shown to be NP-hard, several meta-heuristic algorithms based on tabu search (TS) and imperialist competitive algorithm are developed to heuristically solve the problem. In order to find the best meta-heuristic algorithm, random test problems, ranging in size from small, medium, to large are created and solved by the meta-heuristic algorithms. Then, a detailed statistical experiment, based on split-plot design is... 

    Robust Optimization of Integrated Model of Facility Location and Scheduling

    , M.Sc. Thesis Sharif University of Technology Imanpoor Yourdshahy, Mona (Author) ; Modarres Yazdi, Mohammad (Supervisor)
    Abstract
    In facility location problem with uncertain data, some model parameters such as demand or transportation time are not known in advance and in many cases, no historical information exists to derive their probability distribution functions. In this situation, robust optimization is a prevalent approach. In this study, to apply robust optimization in our model, first we review its concepts and methods. Then, a mathematical model for a new facility location problem, as well as its robust counterpart is developed. Furthermore, we also develop a model for simultaneous decision making regarding facility location problem and sequencing. In this model, it is also assumed the process times are... 

    Minimizing the Number of Breaks in Double Round Robin Tournaments with Different Permutation of Rounds in 2nd Half Season

    , M.Sc. Thesis Sharif University of Technology Yektamaram, Ali Reza (Author) ; Salmasi, Nasser (Supervisor)
    Abstract
    Sports scheduling with its interesting theory and application has been the subject of many research recently. Different problems arise from different league structures with different objectives. Inspired by the structure of soccer leagues in Britain and Netherlands, we study structures in which a different permutation of first half-season rounds is played during second half-season. Some leagues like Premier league in addition to this structure have a special property in which two teams may do not play against each other in the first half-season and play twice in the second half-season. Therefore, we study both structures separately. We present a mathematical model to cover both structures.... 

    Using Decentralized Approach in Power Plants Preventive Maintenance Scheduling Problem

    , M.Sc. Thesis Sharif University of Technology Jabbari, Arman (Author) ; Modarres Yazdi, Mohammad (Supervisor)
    Abstract
    In this paper, a new method for handling power plants preventive maintenance scheduling problem is proposed in which a decentralized framework is applied in order to help the electricity markets to prevent data sharing. The new approach is the extension of alternating direction method of multipliers (ADMM) along with several heuristics and refinements to omit the effect of non-convexity of the problem. Since, the new methodmerely needs minimal information exchange, it is completely practical. In order to evaluate the performance of the proposed method, a case study based on generating system of Iran is presented. It is shown that the proposed model obtains acceptable results  

    Robust Scheduling to Hedge Against Processing Time Uncertainty in Flow Shop

    , M.Sc. Thesis Sharif University of Technology Golgoli, Majid (Author) ; Salmasi, Naser (Supervisor)
    Abstract
    This study focuses on two-machine flow shop problem where processing times are uncertain and the objective function is makespan. All information available about the processing time is an upper and lower bound and also expected value. The min-max and min-max regret version of the problem are adopted. In this study, in order to control the degree of conservatism of the solution, we suppose in each scenario the number of processing times on each machine that can deviate from its expected value is controllable. By considering the duality theorem, we present a mixed-integer programming model for the min-max problem. For each of two problems, we present an algorithm for finding objective value. We... 

    Generalized Tardiness Flow Shop Problem

    , M.Sc. Thesis Sharif University of Technology Meshkinfam, Sareh (Author) ; Shavandi, Hassan (Supervisor)
    Abstract
    In this thesis, several metaheusristic algorithms for solving the generalized tardiness flow shop problem are proposed. In the generalized tardiness flowshop a due date is defined for every operation of the jobs. With the best of our knowledge is the first attempt to develop a genetic algorithm for the proposed problem. Several genetic algorithms are develpoed based on selecting the parents.The proposed GAs are tunned using experimtal analysis and the efficiency of lgorithms are analyzed with many randomly generated problems. Sensitivity analysis is also done to drive mangerial insights  

    Single Base Variant Calling Based on Reference Genome and Reads

    , M.Sc. Thesis Sharif University of Technology Ghareghani, Maryam (Author) ; Khazaei, Shahram (Supervisor) ; Motahari, Abolfazl (Co-Advisor)
    Abstract
    Genome sequencing is one of the fundamental problems in today’s Biology. It has applications in significant problems such as finding association between an individual’s genome sequence and his phenotypes, discovering new genes, and finding evolutionary relations between organisms. Following the rapid advances in sequencing technologies and generation of a huge amount of short reads, efficient computational tools are needed for processing sequencing data. Shortness of reads is a factor that makes the task of reconstructing repetitive genomic regions complicated. In fact, the main challenge in both sequencing and resequencing problems is reconstruction of repeat regions. Common resequencing... 

    Optimizing Merged Machining Operations of Integrated Numerical Controllers based on ISO 10303:238 (STEP-NC)

    , M.Sc. Thesis Sharif University of Technology Beheshti, Mina (Author) ; Houshmand, Mahmoud (Supervisor) ; Fttahi, Omid (Supervisor)
    Abstract
    Right now, the common standard for programming of CNC machines is ISO6983 which is also called G-code. This standard provides very low level information that only contains information about basic measurements and tool movements. Moreover, it splits the CAD/CAM/CNC chain and makes it difficult to gather feedback from shop floor. A global attempt led to development of a new data model for programming CNC machines. STEP-NC standard which is developing based on STEP is aimed to resolve shortages of G-code. The STEP-NC based controllers, can be categorized into three major groups in terms of programming: indirect, interpreted and adaptable. In this project, in order to develop the third category... 

    Determining the Sequence of Loading and Unloading the Trucks in Cross-docks under the Condition of Uncertainty

    , M.Sc. Thesis Sharif University of Technology Sadeghi, Nafiseh (Author) ; Akbari Jokar, Mohammad Reza (Supervisor)
    Abstract
    Todays, given the existence of a strong competitive environment in the industry, supply chains should be quick and reactive, in addition to keeping their costs down. Transit warehouses and warehousing issues are one of the most efficient techniques that reduce inventory costs, while increasing the flow of goods and shorter transport cycles. Regardless of how a warehouse system is designed, the allocation and sequencing of input and output trucks to platforms is considered necessary. The inappropriate sequence of input and output trucks on the platforms increases the completion time of the operation. Also, the uncertainty and unpredictable circumstances of the real world make planning and... 

    Phase-type Distribution in the Sequencing and Scheduling Problem and its Application in Operating Room Problem

    , Ph.D. Dissertation Sharif University of Technology Varmazyar, Mohsen (Author) ; Salmasi, Nasser (Supervisor) ; Modarres, Mohammad (Supervisor)
    Abstract
    Operating rooms (ORs) are considered as the most valuable resource in hospital, which are the largest revenue generator and, at the same time, the largest cost center of hospitals. Hospital managers have been interested in improving the efficiency and effectiveness of ORs by developing modern planning and scheduling tools. This research studies the stochastic operating room (OR) scheduling problem integrated by Post-Anesthesia Care Unit (PACU), named the operating theater room (OTR) problem. Due to the inherent uncertainty in surgery duration and its consecutive PACU time, the completion time of the operation of a patient should be modeled as the sum of a number of random variables. Several... 

    A Multi-Product Scheduling Model Focusing on Logistic Service Sharing in Cloud Manufacturing Systems

    , M.Sc. Thesis Sharif University of Technology Akhavan Hariri, Masoumeh (Author) ; Fatahi Valilai, Omid (Supervisor)
    Abstract
    Cloud computing is a service-driven business model that connects distributed resources and allows multiple service demaders to submit requests simultaneously to a cloud platform via the Internet. An important issue in cloud environments is how to allocate tasks to optimize the performance of a cloud manufacturing system. Allocation of tasks in cloud manufacturing refers to the process of selecting and assigning service providers to manufacturing resources such as design, engineering, machining, testing, and packing to achieve the satisfaction level in terms of time, cost, service availability, and other quality service criteria. Task allocation is an intrinsic part of the cloud manufacturing... 

    A Multio Bjective Work Flow Scheduling Algorithmin Cloud Computing Environment

    , M.Sc. Thesis Sharif University of Technology Safavi, Soroush (Author) ; Qasemi Tari, Farhad (Supervisor) ; Hajji, Alireza (Supervisor)
    Abstract
    Multi core processors are becoming mainstream in the computation area, wide application of multi core processors in Engineering, Industrial purposes and scientific applications made them popular among users and Manufacturers, cloud computing is a very well known Concept which technically is a Multicore processing environment, most of Businesses, enterprises and engineering works nowadays are getting done by the help of cloud services, hence, to get the best of these multi core cloud computing systems, scheduling of the tasks on the cores and virtual machines(VMs) is necessary, which is the answer to two questions: each task must be assigned to which core(VM)? And What is the order of... 

    Meta-Heuristic Algorithm for Minimization of Total Tardiness in Flexible Flow Shop Scheduling Problems

    , M.Sc. Thesis Sharif University of Technology Gharehbaghi, Alireza (Author) ; Salmasi, Nasser (Supervisor) ; Shavandi, Hassan (Co-Supervisor) ; Najafi, Amir Abbas (Co-Supervisor)
    Abstract
    This study deals with the heuristic solution of flexible flow shop scheduling problems with unrelated parallel machines. No preemption of jobs is allowed. As an objective function, this paper considers the minimization of total tardiness. As a first step to propose solution, two different mixed integer mathematical models are developed which tackle the problem at hand. The problem is NP-hard and thus the developed mathematical program can only solve problem instances for small sizes in a reasonable amount of time. The next step is to build heuristics which can provide feasible solutions in polynomial time for larger problem instances. Then in the study develops a constructive heuristic for... 

    An Optimization Model for Designing an Appointment-Making Procedure for Outpatients–Case Study: Milad Hospital Clinic

    , M.Sc. Thesis Sharif University of Technology Mesgari, Sara (Author) ; Eshghi, Kourosh (Supervisor) ; Delavari, Vahid (Co-Supervisor)
    Abstract
    Patient scheduling is one of the most important problems in healthcare optimization which has been in center of attention in various environments including outpatient clinics and operating rooms. Effective scheduling systems have the goal of matching the demand with capacity so that resources are better utilized and patient waiting times are minimized. Furthermore, patient scheduling can be merged with another problem in which the main goal is to find the optimal sequence of a given list of patients. Moreover, there are several sources of uncertainty such as patients’ unpunctuality, absence, and service time in this problem resulting in having a very complex problem. In this research,... 

    Flight Management of an E-VTOL Fleet Using ANFIS Network

    , M.Sc. Thesis Sharif University of Technology Jahanbakhsh, Amir Mohammad (Author) ; Malaek, Mohammad Bagher (Supervisor)
    Abstract
    Much research has been done in the field of queuing or forecasting aircraft routes. These methods have been implemented mainly for commercial aircraft, and little research has been done on electric birds. In this research, we intend to extend these methods to the field of electric birds and create a database based on the existing records of successful flights that electric birds have had in the landing phase. Next, design an intelligent learning system that adjusts its parameters and has the ability to predict the route for birds planning to land at an airport. This intelligent system can manage the birds that are going to land with high computational speed and keep it up to date by adding... 

    An Optimized Graph-Based Structure for Single-Cell RNA-Seq Cell-Type Classification Based on Nonlinear Dimension Reduction

    , M.Sc. Thesis Sharif University of Technology Laghaee, Pouria (Author) ; Koohi, Somayyeh (Supervisor)
    Abstract
    As sequencing technologies have advanced in the field of single cells, it has become possible to investigate complex and rare cell populations and discover regulatory relationships between genes. The detection of rare cells has been greatly facilitated by this technology. However, due to the large volume of data and the complex and uncertain distribution of data, as well as the high rate of technical zeros, the analysis of single cell data clusters remains a computational and statistical challenge. Dimensionality reduction is a significant component of big data analysis. Machine learning methods provide the possibility of better analysis by reducing the non-linear dimensions of data. A graph...