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Design of Setting Group-Based Overcurrent Protection Scheme for Active Distribution Networks Using MILP

IEEE TRANSACTIONS ON SMART GRID 2021年第2期12卷 1185-1193页

作者： Ghotbi-Maleki, Mahdi Chabanloo, Reza Mohammadi Zeineldin, Hatem H. Miangafsheh, Seyed Mohammad Hosseini Shahid Beheshti Univ Dept Elect Engn Tehran *** Iran Cairo Univ Fac Engn Giza 12316 Egypt

In active distribution networks, system reconfiguration and connection/disconnection of distributed generation (DG) can result in protection coordination failure of overcurrent relays. Determining one set of optimal relay settings that would satisfy all possible network topologies is either infeasible or results in high relay operating times. To address this problem, recently the concept of clustering the various network topologies into a limited set is proposed where an optimal Setting Group (SG) is determined for each network topology cluster. This article proposes a novel problem formulation that simultaneously obtains the optimal relay SG and network topology clusters. Due to the complexity and non-linearity of the SG protection coordination problem, the SG protection coordination problem is reformulated as a mixed-integer linear programming (MILP) problem. The effect of the relay characteristic type on reducing the operating times of relays is also investigated. Comparative analysis is provided that highlight the superior performance of MILP over other heuristic optimization techniques. Data exchange between circuit breakers, DGs, CPU and relays are developed based on the IEC 61850 standard to illustrate the implementation of the proposed adaptive protection scheme on real networks.

关键词： Relays Network topology Circuit breakers Fault currents IEC Standards Adaptive systems Active distribution network adaptive protection distributed generation mixed integer linear programming

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Grocery distribution plans in urban networks with street crossing penalties

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NETWORKS 2021年第3期78卷 248-263页

作者： Cerrone, Carmine Cerulli, Raffaele Sciomachen, Anna Univ Genoa Dept Econ & Business Studies Genoa Italy Univ Salerno Dept Math Fisciano Sa Italy

Following the emergency caused by the Covid-19 pandemic, there is the need, among other measures, to modify urban mobility plans in order to reduce the use of collective public transport, reducing the crowding of people while also preventing traffic congestion through discouraging the use of private vehicles. From this perspective, retail companies operating within cities must also reorganize themselves, considering both the unpredictable requirements of environmental sustainability and the new mobility needs calling for the promotion of bicycles and electric scooters. In this context, we deal with the need to determine minimum cost routes in urban areas for delivering orders placed through e-channels. More precisely, we face a variant of the green vehicle routing problem of heterogeneous fleets, in which the objective function includes environmental impact cost components that differ by vehicle type. Moreover, as a novel issue, attention must be paid to avoid crossing and passing close to bicycle lanes;therefore, penalties are associated with the transit of vehicles near bicycle lanes. To address this problem, we propose a mixed integer linear programming model and a matheuristic associated with it. The proposed approach is then used to analyze different scenarios derived from the transportation network of the city of Milan, Italy. Milan is one of the smartest cities in Europe from the mobility point of view but also one of the most affected by the Covid-19 pandemic, and the municipality is making a big investment to promote the use of bicycles.

关键词： delivery problem matheuristic mixed integer linear programming urban networks

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Mathematical optimization approach for facility layout on several rows

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OPTIMIZATION LETTERS 2021年第1期15卷 9-23页

作者： Anjos, Miguel F. Vieira, Manuel V. C. Univ Edinburgh Sch Math Edinburgh Midlothian Scotland GERAD Montreal PQ Canada Univ Nova Lisboa Fac Ciencias & Tecnol Dept Matemat Lisbon Portugal Univ Nova Lisboa CMA Lisbon Portugal

The facility layout problem is concerned with finding an arrangement of non-overlapping indivisible departments within a facility so as to minimize the total expected flow cost. In this paper we consider the special case of multi-row layout in which all the departments are to be placed in three or more rows, and our focus is on, for the first time, solutions for large instances. We first propose a new mixed integer linear programming formulation that uses continuous variables to represent the departments' location in bothxandycoordinates, wherexrepresents the position of a department within a row andyrepresents the row assigned to the department. We prove that this formulation always achieves an optimal solution with integer values ofy, but it is limited to solving instances with up to 13 departments. This limitation motivates the application of a two-stage optimization algorithm that combines two mathematical optimization models by taking the output of the first-stage model as the input of the second-stage model. This algorithm is, to the best of our knowledge, the first one in the literature reporting solutions for instances with up to 100 departments.

关键词： Facilities planning and design Unequal-areas facility layout Row layout mixed integer linear programming Continuous optimization

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Joint Optimization of Planning and Operation in Multi-Region Integrated Energy Systems Considering Flexible Demand Response

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IEEE ACCESS 2021年 9卷 75840-75863页

作者： Gao, Shan Song, Tiancheng E. Liu, Sai Zhou, Cheng Xu, Chenkai Guo, Haomin Li, Xiaogang Li, Zheng Liu, Yu Jiang, Weiyi Wang, Juncheng Wang, Sicheng Southeast Univ Sch Elect Engn Nanjing 210096 Peoples R China State Grid Jiangsu Elect Power Co Ltd Maintenance Branch Co Nanjing 211102 Peoples R China State Grid Jiangsu Elect Power Co Ltd Kunshan Power Supply Branch Co Kunshan 215300 Peoples R China State Grid Fujian Elect Power Co Ltd Xiamen Power Supply Co Xiamen 361004 Peoples R China

The multi-region integrated energy system (MRIES) is one promising option for exploiting the complementarity potentials between power system, thermal system and loads, as well as improving flexibility and economic competitiveness. However, the optimal planning has remained challenging since it involves multiple forms of energies with the nature of coupling. A mixed integer linear programming (MILP) model is proposed for joint optimization of MRIES planning and operation, which considers the flexible load's demand response (DR). It is realized by combining the multi-region heating network IES coupling model with the flexible cooling-heating-electric load DR model. The results show that the proposed model can assist planners to comprehensively analyze and evaluate the impacts of multiple factors on planning, and to determine the optimal planning configuration and operation strategy.

关键词： Heating systems Planning Load modeling Resistance heating Pipelines Maintenance engineering Capacity planning Multi-region integrated energy system regional thermal network flexible demand response planning and operation mixed integer linear programming

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Optimal scan planning with enforced network connectivity for the acquisition of three-dimensional indoor models

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ISPRS JOURNAL OF PHOTOGRAMMETRY AND REMOTE SENSING 2021年 180卷 103-116页

作者： Dehbi, Youness Leonhardt, Johannes Oehrlein, Johannes Haunert, Jan-Henrik Univ Bonn Inst Geodesy & Geoinformat Bonn Germany

The positioning of laser scanners for indoor surveying is still a time and cost expensive process. This article proposes an optimization approach for computing an admissible sensor placement with the minimal number of sensor view point positions. The approach facilitates both wall and floor surveying based on a floorplan of the study object. Optimal solutions are calculated by solving an integer linear Program that respects manufacturer specifications incorporating constraints such as full coverage. To enable a subsequent coregistration of the scans, a flow-based constraint formulation ensuring the connectivity of the selected positions in an appropriately defined geometric intersection graph is introduced. The method has been evaluated on real-world objects and compared to heuristic methods that have frequently been used for related problems. Our solutions outperform heuristic approaches regarding both running time and the number of TLS stations. In a case study with a larger floorplan of an institute building and with different parameter settings, our method resulted in a solution with at least two stations less compared to a solution generated by an expert.

关键词： Art Gallery Problem Terrestrial laser scanning View planning Indoor mixed integer linear programming Optimization

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Urban Traffic Light Control Considering Capacity Difference Between Public Bus and Private Vehicles

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IEEE ACCESS 2021年 9卷 142664-142680页

作者： Liu, Zicheng Wu, Naiqi Gao, Kaizhou Macau Univ Sci & Technol Inst Syst Engn Collaborat Lab Intelligent Sci & Syst Taipa Macao Peoples R China Guangdong Univ Technol State Key Lab Precise Elect Mfg Technol & Equipme Guangzhou 510006 Peoples R China

Due to the rapid growth of transportation demand for economic development, the importance of effective urban traffic signal control can never be underestimated, and the severe space saturation greatly limit the operations of a transportation system. In this paper, public buses and other vehicles are treated as different traffic flows. We address the urban traffic signal control problem in a scheduling framework by considering that the capacity of a public bus is much greater than that of other vehicles. The dynamics of an urban traffic network controlled by traffic lights are described by a novel model, which is formed by inserting mixed logical constraints into a cell transmission flow dynamic model. It includes the nonlinear relationship among the current link volume from the upstream, the current remaining link capacity from the downstream, and the state of the traffic lights. With the objective of minimizing the total delay time in a traffic network for people in the private vehicles and buses, we obtain a mixed integer linear programming formulation, which is built from the traffic signal control problem. We further analyze the influence of the number of passengers on buses and the time interval. The efficiency of the proposed method is verified by making comparisons between the models with and without considering the public transport regular. When the average number of passengers on a bus increases from 10 to 60, the degree of optimization ranges from 17% to 51% for the two-stage model and from 4% to 26% for the four-stage model. Finally, we consider the case without bus lanes and show the importance of dedicated bus lanes.

关键词： Licenses Delays Dynamic scheduling Vehicle dynamics Turning Transportation Schedules Public transportation system urban traffic signal scheduling mixed integer linear programming

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Optimizing tactical harvest planning for multiple fruit orchards using a metaheuristic modeling approach

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EUROPEAN JOURNAL OF OPERATIONAL RESEARCH 2021年第1期290卷 297-312页

作者： Gomez-Lagos, Javier E. Gonzalez-Araya, Marcela C. Soto-Silva, Wladimir E. Rivera-Moraga, Masly M. Univ Talca Programa Magister Gest Operac Fac Ingn Campus CuricoCamino Los Niches Km 1 Curico Chile Univ Talca Dept Ind Engn Fac Engn Campus CuricoCamino Los Niches Km 1 Curico Chile Univ Catolica Maule Fac Ciencias Ingn Dept Computat & Ind Av San Miguel 3605 Talca Chile

In a fruit harvest season, the fruit must be collected during a relatively short period of intense activity. Moreover, large fruit export companies commonly manage multiple orchards where the resources and labor are shared, making the decision process more complex. In this study, we address this harvest problem by proposing a mixed integer linear programming model for supporting tactical decisions during the harvest season in order to reduce total costs. This includes costs related to the fruit not reaching maturity and the number of harvest days. Due to the difficulty of solving this model optimally when real cases are considered, we developed a GRASP metaheuristic method. We compared the GRASP metaheuristic solution to the best integer solution obtained by an exact method using a real case. We observed that the metaheuristic produced a solution in less computational time than the best integer solution. The total costs obtained by the GRASP metaheuristic were two percent greater than the total cost obtained by the best integer solution. Additionally, we analyzed two scenarios to establish if the joint resource planning of the orchards would allow a cost reduction. The GRASP metaheuristic provides orchard managers with a harvest plan in a timely manner and adds greater flexibility to the decision process. The proposed model can be used to plan the harvesting of a variety of fresh fruits. (C) 2020 Elsevier B.V. All rights reserved.

关键词： OR in agriculture Fresh fruit harvest mixed integer linear programming GRASP metaheuristic Fruit supply chain

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Two-stage robust optimisation for surgery scheduling considering surgeon collaboration

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INTERNATIONAL JOURNAL OF PRODUCTION RESEARCH 2021年第21期59卷 6437-6450页

作者： Wang, Jin Guo, Hainan Tsui, Kwok-Leung Jinan Univ Sch Intelligent Syst Sci & Engn Inst Phys Internet Zhuhai Campus Zhuhai Peoples R China Shenzhen Univ Coll Management Res Inst Business Analyt & Supply Chain Managemen Shenzhen 518060 Peoples R China City Univ Hong Kong Sch Data Sci Hong Kong Peoples R China Virginia Tech Grado Dept Ind & Syst Engn Blacksburg VA 24061 USA

Operating rooms (ORs) account for a significant proportion of the costs of maintaining a hospital. Surgery scheduling is optimised to reduce the costs in ORs. However, an important issue that directly affects surgery scheduling is often neglected, i.e. surgeon collaboration. In reality, a surgery requires two surgeons: the main surgeon and an assistant. The surgeon of one surgery might be assigned as the assistant of another surgery. Thus, this paper proposes a two-stage robust model that considers such collaborations. In Stage 1, it determines surgery allocations and surgeon assignments, while in Stage 2, the start time of each surgery is decided. The properties of the solutions are detected, based on which we develop a simple algorithm to solve the two-stage model. In addition, the column-and-constraint generation algorithm is applied to solve the model with a large number of surgeries. The numerical experimentation shows the good performances of the proposed models and algorithms.

关键词： Surgeon collaboration surgery scheduling multi-stage model mixed integer linear programming applications in healthcare systems

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An adaptive large neighbourhood search algorithm for diameter bounded network design problems

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JOURNAL OF HEURISTICS 2021年第5期27卷 887-922页

作者： Garraffa, Michele Mehta, Deepak O'Sullivan, Barry Ozturk, Cemalettin Quesada, Luis Univ Coll Cork Sch Comp Sci & IT Cork Ireland Univ Coll Cork Insight Ctr Data Analyt Sch Comp Sci & IT Cork Ireland Munster Technol Univ Proc Energy & Transport Engn Bishopstown Cork T12 P928 Ireland

This paper focuses on designing a diameter - constrained network where the maximum distance between any pair of nodes is bounded. The objective considered is to minimise a weighted sum of the total length of the links followed by the total length of the paths between the pairs of nodes. First, the problem is formulated in terms of mixed integer linear programming and Constraint programming to provide two alternative exact approaches. Then, an adaptive large neighbourhood search (LNS) to overcome memory and runtime limitations of the exact methods in large size instances is proposed. Such approach is based on computing an initial solution and repeatedly improve it by solving relatively small subproblems. We investigate various alternatives for finding an initial solution and propose two different heuristics for selecting subproblems. We have introduced a tighter lower bound, which demonstrates the quality of the solution obtained by the proposed approach. The performance of the proposed approach is assessed using three real-world network topologies from Ireland, UK and Italy, which are taken from national telecommunication operators and are used to design a transparent optical core network. Our results demonstrate that the LNS approach is scalable to large networks and it can compute very high quality solutions that are close to being optimal.

关键词： Diameter bounded network design mixed integer linear programming Constraint programming Large neighbourhood search Optical networks

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A note to: A multiple-rule based constructive randomized search algorithm for solving assembly line worker assignment and balancing problem

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JOURNAL OF INTELLIGENT MANUFACTURING 2021年第8期32卷 2121-2124页

作者： Michels, Adalberto Sato Costa, Alysson M. Univ Melbourne Sch Math & Stat Melbourne Vic Australia

Some of the solutions reported in a recent paper (Akyol and Baykasoglu in J Intell Manuf 30(2):557-573, 2019.) are infeasible, jeopardising the conclusion that "best results for the 75% of the 320 test instances for the ALWABP-2" were obtained. In this note, we explore the contributions of the paper, show that some of the solutions are indeed infeasible and point out possible inconsistencies in the employed heuristic that may be causing this issue.

关键词： Assembly line balancing Worker assignment mixed integer linear programming

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