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linear-programs
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Stochastic security constrained unit commitment incorporating demand side reserve
, Article International Journal of Electrical Power and Energy Systems ; Volume 56 , March , 2014 , Pages 175-184 ; ISSN: 01420615 ; Hosseini, S. H ; Sharif University of Technology
Abstract
Increasing the social welfare and achieving real competitive markets are the main purposes of consumers participation in electricity markets. Hence, Demand Response Programs (DRPs) have been designed to consider the consumers participation. One of these programs named Emergency Demand Response Program (EDRP) is based on consumers' responses to high electricity prices and to the incentives that are paid by Independent System Operators (ISOs) in the critical hours. In this paper, a model has been proposed for EDRP participation in the Stochastic Security Constrained Unit Commitment (SCUC) program. Both the spinning reserve and the demand side reserve, which is modeled as EDRP, are taken into...
Multi-objective optimization for sustainable development of the power sector: An economic, environmental, and social analysis of Iran
, Article Energy ; Volume 161 , 2018 , Pages 493-507 ; 03605442 (ISSN) ; Aryanpur, V ; Sharif University of Technology
Elsevier Ltd
2018
Abstract
This paper aims to analyze Iran's long-term power sector development from economic, environmental, social, and sustainable perspectives. For this purpose, a linear programming model is developed, which includes three objective functions: minimization of costs, minimization of CO2 emissions, and maximization of created jobs. To provide a sustainable plan, analytical hierarchy process is employed to allocate expert-based weights to the objective functions. Moreover, to support the decision-makers, Pareto-optimal alternatives are explored by varying the weights of objectives. The multi-objective model is solved by applying a weighted method based on fuzzy membership functions. The results show...
A linear programming optimization model for optimal operation strategy design and sizing of the CCHP systems
, Article Energy Efficiency ; Volume 11, Issue 1 , 2018 , Pages 225-238 ; 1570646X (ISSN) ; Sharif University of Technology
Springer Netherlands
2018
Abstract
Combined cooling, heat, and power (CCHP) system offers numerous potential advantages for the supply of energy to residential buildings in the sense of improved energy efficiency and reduced environmental burdens. To realize the potential for being more beneficial, however, such systems must reduce total costs relative to conventional systems. In this study, a linear programming optimization model was presented for optimum planning and sizing of CCHP systems. The purpose of the model is to give the design of the CCHP system by considering electrical chiller and absorption chiller simultaneously in economic viewpoint. A numerical study was conducted in Tehran to evaluate the CCHP system model....
Optimal operation of a virtual power plant in frequency constrained electricity market
, Article IET Generation, Transmission and Distribution ; Volume 13, Issue 11 , 2019 , Pages 2015-2023 ; 17518687 (ISSN) ; Rayati, M ; Ranjbar, A. M ; Sharif University of Technology
Institution of Engineering and Technology
2019
Abstract
In this study, 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 modelled as a bi-level optimisation problem. In the upper-level problem, the total profit of VPP is maximised. In the lower-level problem, the clearing conditions of frequency constrained electricity market are modelled. The proposed bi-level optimisation problem is reformulated as a mathematical programming with equilibrium constraints (MPEC) problem by using Karush-Kuhn-Tucker conditions. Then, the proposed MPEC problem, which is non-linear and hard to solve by commercial solvers,...
Optimal equilibrium selection of price-maker agents in performance-based regulation market
, Article Journal of Modern Power Systems and Clean Energy ; Volume 10, Issue 1 , 2022 , Pages 204-212 ; 21965625 (ISSN) ; Sheikhi, A ; Ranjbar, A. M ; Sun, W ; Sharif University of Technology
State Grid Electric Power Research Institute Nanjing Branch
2022
Abstract
This paper analyzes the oligopolistic equilibria of multiple price-maker agents in performance-based regulation (PBR) markets. In these markets, there are price-maker agents representing some frequency regulation (FR) providers and a number of independent price-taker FR providers. A model of equilibrium problem with equilibrium constraints (EPECs) is employed in this paper to study the equilibria of a PBR market in the presence of price-maker agents and price-taker FR providers. Due to the incorporation of the FR providers' dynamics, the proposed model is reformulated as a mixed-integer linear programming (MILP) problem over innovative mathematical techniques. An optimal equilibrium point is...
A two-phase linear programming methodology for fuzzy multi-objective mixed-model assembly line problem
, Article International Journal of Advanced Manufacturing Technology ; Volume 44, Issue 9-10 , 2009 , Pages 1010-1023 ; 02683768 (ISSN) ; Javadi, B ; Sahebjamnia, N ; Mahdavi Amiri, N ; Sharif University of Technology
2009
Abstract
We develop a fuzzy multi-objective linear programming (FMOLP) model for solving multi-objective mixed-model assembly line problem. In practice, vagueness and imprecision of the goals in this problem make the fuzzy decision-making complicated. The proposed model considers minimizing total utility work, total production rate variation, and total setup cost, using a two-phase linear programming approach. In the first phase, the problem is solved using a max-min approach. The max-min solution not being efficient, in general, we propose a new model in the second phase to maximize a composite satisfaction degree at least as good as the degrees obtained by phase one. To show the effectiveness of...
, M.Sc. Thesis Sharif University of Technology ; Vaziri, Manouchehr (Supervisor)
Abstract
As petroleum resources are not steadily distributed in the world and all industries and manufacturing sections are dependent on these resources, petroleum transportation is very important to the extent that availability of these resources occurs in the fastest time and costing the least possible. The objective of this study is to study the petroleum distribution through time in the world and assess its transportation efficacy during 1965-2005 in 173 countries. Collecting information about petroleum distribution between exporting countries to importing ones helped to complete the study data base. Also in this study two transportation networks, sea and land multimodal transportation network...
Joint Disrtibuted Source and Network Coding
, M.Sc. Thesis Sharif University of Technology ; Movaghar Rahimabadi, Ali (Supervisor)
Abstract
Network coding, as a novel technique, suggests that the intermediate nodes of a network can combine independent flows to optimize the usage of a shared communication channel. Also, distributed source coding, exploits the joint statistics of correlated information sources to reduce the volume of transmitted information. Surprisingly, it has been shown that linear network codes are able to compress correlated sources. In this project, we have focused on this problem, i.e. joint distributed source and network coding. We have two important contributions with different directions. First we give a practical design for joint coding. Second, we use an evolutionary approach to find the best placement...
Primal-Dual Algorithms for Linear Programming Based on the Logarithmic Barrier Method
,
M.Sc. Thesis
Sharif University of Technology
;
Mahdavi Amiri, Nezameddin
(Supervisor)
Abstract
We deal with primal-dual interior point methods for solving the linear programming problem.Taken from recent literature on interior point methods, we discuss a short-step and a long-step path-following primal-dual method and show how to have polynomial-time bounds for both methods. The iteration bounds are for the short-step variant and for the long-step variant. In the analysis of both variants, a new proximity measure is used, which is closely related to the Euclidean norm of the scaled search direction vectors. The analysis of the long-step method depends strongly on the fact that the usual search directions form a descent direction for the so-called primal-dual logarithmic barrier...
Modeling and Design of CCHP System for Sharif Energy Research Institute
, M.Sc. Thesis Sharif University of Technology ; Sabbohi, Yadollah (Supervisor)
Abstract
The aim of the present research project has been techno-economical analysis of using a CCHP (Combined Cooling Heating and Power) technology at the building of Sharif Energy Research Institute (SERI). The CCHP at SERI is supposed to supply energy required at the building. Useful energy demand at the building include heating in winter, cooling and air conditioning in summer, lighting and power requirement of electric appliance and equipments. Since there are many technologies that could be utilized as CCHP, an optimal model of energy supply system of the building has been developed in order to identify the most appropriate technology. The application of model has enabled techno logical...
Drought Management by Utilizing Water Trading Models (Case study: East Azarvbayjan, Orumieh River Basin)
,
M.Sc. Thesis
Sharif University of Technology
;
Abrishamchi, Ahmad
(Supervisor)
Abstract
The extended drought in the Orumieh River Basin has caused severe problems for Orumieh Lake. Due to the fact that agriculture is the biggest user of water resources in this region, effective management of groundwater and surface water resources plays an important role in management of Orumieh lake`s condition. In this situation, “water trading” by designing an efficient “smart market” seems to be a viable option; A market with lower transaction costs which can be adaptable to changing demands and being able to optimize economic benefit within the environmental constraints. This market works by reallocating water among users who intend to sell their excess water and those who prefer to buy...
Primal-Dual Column Generation Method and Column Generation Decomposition with Degeneracy
, M.Sc. Thesis Sharif University of Technology ; Mahdavi Amiri, Nezameddin (Supervisor)
Abstract
Column generation technique has became a very important tool in the solution of linear programming problems. Column generation techniques start with solving a reduced version of the master problem. Recently, variations of the standard column generation approach have been proposed which use interior point of the dual feasible set instead of optimal slutions. So, primal-dual column generation technique uses a primal-dual interior point method to obtain well-centered non-optimal solutions of the restricted master problem. We show that the method converges to an optimal solution of the master problem. Then, an improved primal simplex algorithm (IPS) for degenerate linear problems is proposed....
A Study of Trade and Transportation Trends in Asia
, M.Sc. Thesis Sharif University of Technology ; Vaziri, Manouchehr (Supervisor)
Abstract
Considering the extensive developments achieved up to now in the fields of trade and international transportation, as well as the key role of the freight transportation in the economical development of a zone or a country, the present research, titled “A Study of the Trade and Transportation Trends”, was planned. The available data concerning the trade of six types of the goods according to The United Nations Classification (SITC), within the period 1965-2005, have been analyzed in this research. The study has been focused on the Asian Multimodal Network constituted of 31 countries. Trading centre of each country in the selected network is assumed to be located in its capital town. The...
Development of a Model for Energy, Environmental and Technical Evaluation in Iron and Steel Industry
, M.Sc. Thesis Sharif University of Technology ; Saboohi, Yadollah (Supervisor)
Abstract
The iron and steel industry has faced several challenges during the recent years. There has always been an aspiration towards higher economic profitability for the system. During the mid 1970s and 1980s the energy crises caused a dramatic rise in energy costs, which led to an increased awareness in energy conservation. In recent years, climate change issues have become more important for the industry. The operating practices for an industrial system are often affected by external restrictions concerning the economical, energy and environmental efficiency of the system. There are a large number of ways to increase the system efficiency, e.g. installation of new process equipment, and practice...
Water Allocation with Regard to Reclaimed Wastewater as a New Water Resource for Tehran, Iran
,
M.Sc. Thesis
Sharif University of Technology
;
Tajrishy, Masoud
(Supervisor)
Abstract
Tehran, the capital of Iran, like many megacities in the world is encountered with increasing freshwater demand and water resources limitation because of the rapid growth of population. In spite of the existence of neighboring water recourses; such as Karaj-Dam, Latian-Dam and Lar-Dam, and large usage of groundwater, the management of urban water demand is one of the biggest problems with this city. In this thesis, water reuse and wastewater recycling are considered as a sustainable solution for water supply and wastewater management of Tehran. A linear programming optimization model with the object of cost minimization is used to allocate water between users and resources, concerning the...
A Dynamic Programming Model to Address Airline Revenue Management
, M.Sc. Thesis Sharif University of Technology ; Modarres Yazdi, Mohammad (Supervisor)
Abstract
In this thesis, we address the Revenue Management problem, when there is cancellation, no-shows, overbooking, and refund constraints. We model this problem using Dynamic Programming. Given the fact that this problem is intractable, we develop a linear programming model that is equivalent to our problem. We first prove that the optimal value of linear programming objective function serves as an upper bound for the Dynamic Program. In the next part we develop a bid-pricing technique, using the shadow prices of the aforementioned linear program, to decide upon rejecting, or accepting the seats, in the network. Using the Monte-Carlo Simulation we show that there is a small distance between the...
Modeling and Solving the Multi-Player Competitive Location Problem in a Continuous Facility Layout
, M.Sc. Thesis Sharif University of Technology ; Eshghi, Kourosh (Supervisor)
Abstract
As time has passed, the cost of maintaining expert human resources has been increasing worldwide; as a result, factories and stakeholder has sought ways to exploit the expertise of their human resources as much as possible so they can reduce their costs and, of course, raise their profits. To achieve this, managers decided to assign their human resources to tasks that demands their expertise and knowledge and therefore provides added value for their companies; nevertheless, this decision needs proper alternatives to do routine and predetermined jobs as substitutions for expert human resources.As the technology and the science has been growing day by day, the use of robots has been extremely...
Optimum Unit Size in Generation Expansion Planning Based on Reliability Criteria
,
M.Sc. Thesis
Sharif University of Technology
;
Fotuhi Firouzabad, Mahmud
(Supervisor)
Abstract
Increasing demand in power systems necessitates the Generation Expansion Planning (GEP) which is to determine the type, size, and location of new generating units in a planning horizon. The final solution of GEP is based on the minimum cost and/or optimum reliability taking into account various constraints such as capacity of units and lines, operating constraints, and budget restrictions. This paper presents a model based on scenarios for generation expansion planning and units retirement decision. The proposed model could be used by vertically integrated utilities as well as the ISOs in electricity markets to obtain generation expansion schemes. In this approach, uncertainty of units are...
Energy Conservation in The Gas Turbines of National Iranian Oil Company Considering Local Operational Conditions
, M.Sc. Thesis Sharif University of Technology ; Sattari, Sourena (Supervisor)
Abstract
Low effiencies of equipments and lack of forecasting heat integration in some oil regions are the reasons of primary energy losses in these regions. Also there have been difficulties in providing electric power demands in regions separate from the state electricity network which is a barrier in front of exploiting all the potentials of the region. This research introduces a model that can lead to selection of optimal configuration of equipments and units in order to establish a CCHP system that answers variable electric, heating and cooling demands ensuring a safe margin of power generation. The model simultaneously has the ability to select between existing and new installable equipments....
Patient Allocation and Scheduling in Healthcare
, M.Sc. Thesis Sharif University of Technology ; Shavandi, Hassan (Supervisor)
Abstract
One of the main applications of revenue management is in healthcare industry. By combining these two concepts, subjects such as patient allocation and scheduling and no-show rates were developed in the literature. Up until now, allocation and scheduling were considered separately in the literature. Also, no-show rates were predicted using regression models and data mining tools and these predictions were rarely used in scheduling systems. In this thesis, we combined allocation based on patients’ insurance type with scheduling based on patients’ no-show rates. Also, patients’ no-show rates were predicted and these rates were used in the proposed scheduling model. Firstly, the integrated...