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mathematical-programming
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Coordinated Strategy of Price-maker Renewable Generation and Thermal Units in Elrctricity Market
, M.Sc. Thesis Sharif University of Technology ; Ranjbar, Ali Mohammad (Supervisor)
Abstract
Wind energy, as a type of renewable energy resource, is clean and is rapidly growing globally. The intermittency in the production of wind energy is the most major obstacle for these producers in a competitive electricity market, to compete with thermal units. Most existing models in the literature mitigate the risk of wind power, by coordinating them with energy storages such as pumped storages power plant. Here, in this thesis, another risk mitigation approach is introduced which combines wind energy and natural gas power plant in an electricity market. In addition, as the penetration level of wind power grows, the wind power producers must be considered as a price-maker player which their...
Optimal Operation of a Price-Maker Virtual Power Plant in Frequency Constrained Electricity Market
, M.Sc. Thesis Sharif University of Technology ; Ranjbar, Ali Mohammad (Supervisor)
Abstract
In this thesis, optimal offering strategy problem of a virtual power plant (VPP) as a price-maker player in day-ahead frequency constrained electricity market is presented. The optimal offering strategy problem is modeled as a bi-level optimization problem. In the upper level, the total profit of VPP is maximized. In the lower level, the clearing conditions of frequency constrained electricity market is modeled. The proposed bi-level optimization problem is reformulated as a mathematical programming with equilibrium constraints (MPEC) problem by using Karush-Kuhn-Tucker (KKT) conditions. Then, the proposed MPEC problem, which is nonlinear and hard to solve by commercial solvers, is...
Simultanous Optimization of Water and Energ in Steel Production Based on Modified Superstructure
, M.Sc. Thesis Sharif University of Technology ; Saboohi, Yadollah (Supervisor)
Abstract
In a steel production plan primary resources entered the process are converted to high value products and byproducts. To this end, resources need to pass several consecutive process that require utility streams. One could not achieve the optimum operation of an industrial process unless they maximize the product and minimize the utility and waste. Therefore, it is important to consider the process stream integrated. The aim of this work is to find the optimum consumption of water and energy in a steel production and to calculate the potential reduction in water and energy resource destruction. Present work could be define a mathematical programing problem in which water users and all streams...
Path-differentiated pricing in congestion mitigation
, Article Transportation Research Part B: Methodological ; Volume 80 , October , 2015 , Pages 202-219 ; 01912615 (ISSN) ; Aashtiani, H. Z ; Lawphongpanich, S ; Yin, Y ; Sharif University of Technology
Elsevier Ltd
2015
Abstract
Instead of charging tolls on individual links, this paper considers doing the same on paths. Path and link tolls are "valid" if they encourage motorists to use routes that collectively lead to a target distribution, e.g., one that minimizes travel delay. Because the numbers of valid link and path tolls are typically infinite, an objective in pricing tolls is to find a set of valid tolls that yields the least revenue to lessen the financial burden on motorists.Path tolls are generally more flexible than link tolls and this paper shows that this flexibility can substantially reduce the financial burden on motorists. Additionally, valid path tolls yielding the least revenue possess...
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) ; 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...
Prioritized K-mean clustering hybrid GA for discounted fixed charge transportation problems
, Article Computers and Industrial Engineering ; Volume 126 , 2018 , Pages 63-74 ; 03608352 (ISSN) ; Hashemi, Z ; Sharif University of Technology
Elsevier Ltd
2018
Abstract
The problem of allocating different types of vehicles for transporting a set of products in an existing transportation network, to minimize the total transportation costs, is considered. The distribution network involves a heterogeneous fleet of vehicles each with the given capacity and with a variable transportation cost and a fixed cost with a discounting mechanism. Due to nonlinearity of the discounting mechanism, a nonlinear mathematical programming model is developed. A prioritized K-mean clustering encoding is introduced to designate the distribution depots distances, their demands, and the vehicles’ capacity. Using this priority clustering, a heuristic routine is developed by which...
A resistive ram-based FPGA architecture equipped with efficient programming circuitry
, Article IEEE Transactions on Circuits and Systems I: Regular Papers ; Volume 65, Issue 7 , 2018 , Pages 2196-2209 ; 15498328 (ISSN) ; Asadi, H ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2018
Abstract
Despite the considerable effort has been put on the application of Non-Volatile Memories (NVMs) in Field-Programmable Gate Arrays FPGAs, previously suggested designs are not mature enough to substitute the state of-the-art SRAM-based counterparts mainly due to the inefficient building blocks and/or the overhead of programming structure which can impair their potential benefits. In this paper, we present a Resistive Random Access Memory RRAM-based FPGA architecture employing efficient Switch Box (SB) and Look-Up Table (LUT) designs with programming circuitry integrated in both SB and LUT designs that creates area and power efficient programmable components while precluding performance...
A Variable neighborhood search algorithm for solving fuzzy number linear programming problems using modified kerre's method
, Article IEEE Transactions on Fuzzy Systems ; Volume 27, Issue 6 , 2019 , Pages 1286-1294 ; 10636706 (ISSN) ; Ghorbani Moghadam, K ; Mahdavi Amiri, N ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2019
Abstract
To solve a fuzzy linear program, we need to compare fuzzy numbers. Here, we make use of our recently proposed modified Kerre's method for comparison of LR fuzzy numbers. We give some new results on LR fuzzy numbers and show that to compare two LR fuzzy numbers, it is not necessary to compute the fuzzy maximum of two numbers directly. Using the modified Kerre's method, we propose a new variable neighborhood search algorithm for solving fuzzy number linear programming problems. In our algorithm, the local search is defined based on descent directions, which are found by solving four crisp mathematical programming problems. In several methods, a fuzzy optimization problem is converted to a...
An efficient heuristic method for joint optimization of train scheduling and stop planning on double-track railway systems
, Article INFOR ; Volume 58, Issue 4 , 2020 , Pages 652-679 ; Ramezani, S ; Farahani, N. V ; Hassannayebi, E ; Abolmaali, S ; Shakibayifar, M ; Sharif University of Technology
University of Toronto Press
2020
Abstract
In this study, a new mathematical programming approach for solving the joint timetabling and train stop planning problem in a railway line with double-track segments is proposed. This research aims to design an optimized train timetable subject to the station- capacity and time-dependent dwell time constraints. The objective function is to maximize the railway infrastructure capacity by minimizing the schedule makespan. The problem is formulated as a particular case of blocking permutation flexible flow shop scheduling model with dynamic time window constraints. Due to the combinatorial nature of the problem, heuristic algorithm and bound tightening methods are proposed that generate...
Linear formulations for topology-variable-based distribution system reliability assessment considering switching interruptions
, Article IEEE Transactions on Smart Grid ; Volume 11, Issue 5 , May , 2020 , Pages 4032-4043 ; Abbaspour, A ; Fotuhi Firuzabad, M ; Muñoz Delgado, G ; Contreras, J ; Lehtonen, M ; Arroyo, J. M ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2020
Abstract
Continuity of supply plays a significant role in modern distribution system planning and operational studies. Accordingly, various techniques have been developed for reliability assessment of distribution networks. However, owing to the complexities and restrictions of these methods, many researchers have resorted to several heuristic optimization algorithms for solving reliability-constrained optimization problems. Therefore, solution quality and convergence to global optimality cannot be guaranteed. Aiming to address this issue, two salient mathematical models are introduced in this paper for topology-variable-based reliability evaluation of both radial and radially-operated meshed...
A time warping speech recognition system based on particle swarm optimization
, Article 2nd Asia International Conference on Modelling and Simulation, AMS 2008, Kuala Lumpur, 13 May 2008 through 15 May 2008 ; 2008 , Pages 585-590 ; 9780769531366 (ISBN) ; Razzazi, F ; Rahmani, A. M ; Gharan, S. O ; Sharif University of Technology
2008
Abstract
In this paper, dynamic programming alignment is replaced by a particle swarm optimization (PSO) procedure in time warping problem. The basic PSO is a very slow process to be applied to speech recognition application. In order to achieve a higher performance, by inspiring of PSO optimization methodology, we introduced a PSO Inspired Time warping Algorithm (PTW) that significantly increase the computational performance of time warping in alignments of long length massive data sets. As a main enhancement, a pruning strategy with an add-in controlling threshold is defined in PTW that causes a considerable reduction in recognition time, while maintaining the system accuracy comparing to DTW. ©...
A multi-objective stochastic programming approach for supply chain design considering risk
, Article International Journal of Production Economics ; Volume 116, Issue 1 , 2008 , Pages 129-138 ; 09255273 (ISSN) ; Brown, K. N ; Tarim, S. A ; Modarres, M ; Sharif University of Technology
2008
Abstract
In this paper, we develop a multi-objective stochastic programming approach for supply chain design under uncertainty. Demands, supplies, processing, transportation, shortage and capacity expansion costs are all considered as the uncertain parameters. To develop a robust model, two additional objective functions are added into the traditional comprehensive supply chain design problem. So, our multi-objective model includes (i) the minimization of the sum of current investment costs and the expected future processing, transportation, shortage and capacity expansion costs, (ii) the minimization of the variance of the total cost and (iii) the minimization of the financial risk or the...
Integrating large scale wind farms in fuzzy mid term unit commitment using PSO
, Article 2008 5th International Conference on the European Electricity Market, EEM, Lisboa, 28 May 2008 through 30 May 2008 ; 2008 ; 9781424417445 (ISBN) ; Vakilian, M ; Sharif University of Technology
2008
Abstract
This paper presents a new approach for unit commitment (UC); where a large scale wind power exists and the wind speed has a fuzzy characteristic; by using particle swarm optimization method (PSO). In this approach, the system reserve requirements, the requirement of having a load balance, and the wind power availability constraints are realized. A proper modeling of these constraints is an important issue in power system scheduling. Since these constraints are "fuzzy" in nature, any crisp treatment of them in this problem may lead to over conservative solutions. In this paper, a fuzzy optimization-based method is developed to solve power system UC problem with a fuzzy objective function and...
Developing a market-oriented approach for supplying flexibility ramping products in a multimicrogrid distribution system
, Article IEEE Transactions on Industrial Informatics ; Volume 17, Issue 10 , 2021 , Pages 6765-6775 ; 15513203 (ISSN) ; Salehi, J ; Moeini Aghtaie, M ; Sharif University of Technology
IEEE Computer Society
2021
Abstract
Rapid growth of the variable and intermittent renewable generation in multimicrogrid distribution network (MMG-DN) has derived a gross violation in power balance due to the scarcity of ramp capacity. To neutralize this shortage, the present study develops a market-oriented approach for supplying flexibility ramping products (FRPs) in an MMG-DN. In this article, the proposed approach appraises a ramping capacity of local microgrids (MGs), which encompass various distributed energy resources through a bilevel programming. To do so, an interval-based security constraint economic dispatch process is accomplished at the upper level considering the network's requirement of upward/downward ramp...
Medical waste management during coronavirus disease 2019 (COVID-19) outbreak: A mathematical programming model
, Article Computers and Industrial Engineering ; Volume 162 , December , 2021 ; 03608352 (ISSN) ; Khalili Nasr, A ; Mostafazadeh, P ; Mina, H ; Sharif University of Technology
Elsevier Ltd
2021
Abstract
Municipal solid waste (MSW) directly impacts community health and environmental degradation; therefore, the management of MSW is crucial. Medical waste is a specific type of MSW which is generally divided into two categories: infectious and non-infectious. Wastes generated by coronavirus disease 2019 (COVID-19) are classified among infectious medical wastes; moreover, these wastes are hazardous because they threaten the environment and living organisms if they are not appropriately managed. This paper develops a bi-objective mixed-integer linear programming model for medical waste management during the COVID-19 outbreak. The proposed model minimizes the total costs and risks, simultaneously,...
Heuristic algorithms to solve a bi-criteria traveling salesman problem with fuzzy time window
, Article 35th International Conference on Computers and Industrial Engineering, ICC and IE 2005, Istanbul, 19 June 2005 through 22 June 2005 ; 2005 , Pages 1899-1904 ; 9755612653 (ISBN); 9789755612652 (ISBN) ; Rabbani, M ; Hakami, M ; Kazemi, M ; Sharif University of Technology
2005
Abstract
This paper presents a mathematical programming to model a bi-criteria traveling salesman problem (TSP) with fuzzy time windows. The objective is to minimize the travel time and minimize the sum of salesman's waiting time during the service. A triangle fuzzy number is defined for the service time of each customer. The objective function is normalized in the interval between 0 and 1. To solve such a model, two heuristic methods based on genetic algorithms (GAs) and ant colony optimization (ACO) are developed. To validate and show the efficiency these methods, a number of test problems are generated at random. Finally, a comparison of the obtained results is presented
A new supply chain distribution network design for two classes of customers using transfer recurrent neural network
, Article International Journal of System Assurance Engineering and Management ; Volume 13, Issue 5 , 2022 , Pages 2604-2618 ; 09756809 (ISSN) ; Nasiri, G. R ; Esmaeili, E ; Davoudpour, H ; Chang, S. I ; Sharif University of Technology
Springer
2022
Abstract
Supply chain management integrates planning and controlling of materials, information, and finances in a process which begins from suppliers and ends with customers. Optimal planning decisions made in such a distribution network usually include transportation, facilities location, and inventory. This study presents a new approach for considering customers’ differentiation in an integrated location-allocation and inventory control model using transfer recurrent neural network (RNN). In this study, a location and allocation problem is integrated with inventory control decisions considering two classes of strategic and non-strategic customers. For the first time, a novel transfer RNN is applied...
Single machine scheduling problem with batch outsourcing
, Article International Journal of Engineering, Transactions B: Applications ; Volume 35, Issue 5 , 2022 , Pages 1006-1016 ; 1728144X (ISSN) ; Kianfar, F ; Sharif University of Technology
Materials and Energy Research Center
2022
Abstract
Outsourcing as a useful strategy in the industry can be integrated into scheduling problems. Moreover, batch outsourcing is a practical assumption owing to the logistics issues for transferring the parts between the manufacturer and the subcontractors. However, this assumption is rarely addressed in the scheduling literature. In this paper, a novel single machine scheduling problem with the option of batch outsourcing is studied. The objective is to minimize the sum of the total completion time of the jobs and the total outsourcing cost. To solve the problem, first, two mixed-integer linear programming (MILP) models, named MP1 and MP2, are developed, which respectively use a straightforward...
Application of ozone treatment and pinch technology in cooling water systems design for water and energy conservation
, Article International Journal of Energy Research ; Volume 34, Issue 6 , 2010 , Pages 494-506 ; 0363907X (ISSN) ; Gharaie, M ; Parand, R ; Panjeshahi, E ; Sharif University of Technology
2010
Abstract
Re-circulating cooling water systems offer the means to remove heat from a wide variety of industrial processes that generate excess heat. Such systems consist of a cooling tower and a heat-exchanger network that conventionally has a parallel configuration. However, reuse of water between different cooling duties allows cooling water networks to be designed in a series arrangement. This results in performance improvement and increased cooling tower capacity. In addition, by the integration of ozone treatment into the cooling tower, the cycle of concentration can be increased. The ozone treatment also dramatically reduces the blow-down that, in turn, is environmentally constructive. In this...
Performance tradeoff of MVNOs in OFDMA-Based virtualized wireless networks
, Article IEEE Transactions on Vehicular Technology ; Volume 71, Issue 1 , 2022 , Pages 697-712 ; 00189545 (ISSN) ; Li, S ; Mokhtari, F ; Derakhshani, M ; Ashtiani, F ; Le-Ngoc, T ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2022
Abstract
In this paper, we analyze the tradeoff between the profits gained by mobile virtual network operators (MVNOs) in an orthogonal frequency division multiple access (OFDMA)-based virtualized wireless network (VWN). In this respect, MVNOs rent the network resources from a mobile network operator (MNO) to create virtual resources based on allocated rates and the cost due to allocated transmit powers in two different strategies: resource-based isolation strategy and rate-based isolation strategy. In resource-based isolation strategy, it is assumed that the whole bandwidth in each base station is divided equally between MVNOs whereas in rate-based isolation strategy, the whole bandwidth in each...