Computers & Operations Research最新文献_第8页

Optimizing the Transport of Organs for Transplantation

IF 4.1 2区工程技术

Computers & Operations Research Pub Date : 2024-12-23 DOI: 10.1016/j.cor.2024.106934

Isaac Balster , Joyce Azevedo Caetano , Glaydston Mattos Ribeiro , Laura Bahiense

{"title":"Optimizing the Transport of Organs for Transplantation","authors":"Isaac Balster , Joyce Azevedo Caetano , Glaydston Mattos Ribeiro , Laura Bahiense","doi":"10.1016/j.cor.2024.106934","DOIUrl":"10.1016/j.cor.2024.106934","url":null,"abstract":"<div><div>As an organ becomes available for transplantation, a recipient must be selected. Usually, donor and recipient are geographically apart. Therefore, the transport of the organ must be planned and executed within the time window imposed by the maximum preservation time of the organ, which can impact recipient selection. The Cold Ischemia Time - CIT, that is the time elapsed between the surgical removal of the organ and its transplantation, must be the minimum possible to improve the transplantation success. In this sense, the air transport becomes the best option and, sometimes, it is the only way to deliver the organ before perishing. The planning of an organ transportation means choosing, among thousands of possible sequences of flights, the option that delivers the organ faster to its destination. This problem can be modeled as a resource constrained shortest path. Given the urgency and importance of this task, which is solved manually in Brazil, we present a labeling algorithm to find the optimal sequence of flights. Computational tests performed on 25 Brazilian real cases showed a reduction, on average, of 37,46% for the CITs and 44,17% for the transport times.</div></div>","PeriodicalId":10542,"journal":{"name":"Computers & Operations Research","volume":"176 ","pages":"Article 106934"},"PeriodicalIF":4.1,"publicationDate":"2024-12-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143165818","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

New models for close enough facility location problems

IF 4.1 2区工程技术

Computers & Operations Research Pub Date : 2024-12-21 DOI: 10.1016/j.cor.2024.106957

Alejandro Moya-Martínez , Mercedes Landete , Juan F. Monge , Sergio García

{"title":"New models for close enough facility location problems","authors":"Alejandro Moya-Martínez , Mercedes Landete , Juan F. Monge , Sergio García","doi":"10.1016/j.cor.2024.106957","DOIUrl":"10.1016/j.cor.2024.106957","url":null,"abstract":"<div><div>Two integer programming problems are introduced and formulated in this paper, both based on the concepts of <em>close enough</em> and facility location. Location problems using the notion of <em>close enough</em> allow customers to pick up their demand at pickup points different from the facilities but that are still not too far from the latter.</div><div>Given a discrete set of customers, a discrete set of potential facility locations, and a maximum distance that each customer is willing to travel free of charge to pick up their order, the Close Enough Facility Location Problem consists in determining which facilities to open among the candidates, on which points on the plane to install pickup points, and how to assign customers to both facilities and pickup points, in an optimal way taking into account different costs. In this work we propose two generalizations of this problem. The first is to consider that the pickup points have capacities. The second is to consider that the communications network is restricted to a graph, and that therefore the pickup points cannot be installed on any point on the plane but only on the network. These problems are named the Capacitated Close-Enough Facility Location Problem and the Network Capacitated Close-Enough Facility Location Problem, respectively. We propose a column generation algorithm for the two introduced problems that allows us to obtain better results for large-scale problems than the CPLEX solver.</div></div>","PeriodicalId":10542,"journal":{"name":"Computers & Operations Research","volume":"176 ","pages":"Article 106957"},"PeriodicalIF":4.1,"publicationDate":"2024-12-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143166432","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Genetic algorithm-based selection of optimal Monte Carlo simulations

IF 4.1 2区工程技术

Computers & Operations Research Pub Date : 2024-12-20 DOI: 10.1016/j.cor.2024.106958

Francesco Strati , Luca G. Trussoni

引用次数: 0

Optimal investment planning for production networks with fixed production profiles

IF 4.1 2区工程技术

Computers & Operations Research Pub Date : 2024-12-20 DOI: 10.1016/j.cor.2024.106955

Donghao Liu , Benjamin D. Leibowicz , Jonathan F. Bard , Yuzixuan Zhu , Yuanyuan Guo , Yufen Shao

{"title":"Optimal investment planning for production networks with fixed production profiles","authors":"Donghao Liu , Benjamin D. Leibowicz , Jonathan F. Bard , Yuzixuan Zhu , Yuanyuan Guo , Yufen Shao","doi":"10.1016/j.cor.2024.106955","DOIUrl":"10.1016/j.cor.2024.106955","url":null,"abstract":"<div><div>In this paper, we consider an oilfield planning problem with decisions about where and when to invest in wells and facilities to maximize profit. The model, in the form of a mixed-integer linear program, includes an option to expand capacity for existing facilities, annual budget constraints, well closing decisions, and fixed production profiles once wells are opened. While fixed profiles are a novel and important feature, they add another set of time-indexed binary variables that makes the problem difficult to solve. To find solutions, we develop a three-phase sequential algorithm that includes (1) ranking, (2) branching, and (3) refinement. Phases 1 and 2 determine which facilities and wells to open, along with well-facility assignments. Phase 3 ensures feasibility with respect to budget constraints and adjusts construction times and facility capacities to increase profit. We first demonstrate how our algorithm navigates the problem’s complex features by applying it to a case study parameterized with realistic production profiles. Then, we perform computational experiments on small instances and show that our algorithm generally achieves the same objective function values as CPLEX but in much less time. Lastly, we solve larger instances using our three-phase algorithm and several variations to demonstrate its scalability and to highlight the roles of specific algorithmic components.</div></div>","PeriodicalId":10542,"journal":{"name":"Computers & Operations Research","volume":"176 ","pages":"Article 106955"},"PeriodicalIF":4.1,"publicationDate":"2024-12-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143166427","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

An efficient MILP-based algorithm for the qualitative flexible multi-criteria method under incomplete or conflicting weights

IF 4.1 2区工程技术

Computers & Operations Research Pub Date : 2024-12-19 DOI: 10.1016/j.cor.2024.106951

Saeed Alaei , Seyed Hossein Razavi Hajiagha , Mahnaz Hosseinzadeh

{"title":"An efficient MILP-based algorithm for the qualitative flexible multi-criteria method under incomplete or conflicting weights","authors":"Saeed Alaei , Seyed Hossein Razavi Hajiagha , Mahnaz Hosseinzadeh","doi":"10.1016/j.cor.2024.106951","DOIUrl":"10.1016/j.cor.2024.106951","url":null,"abstract":"<div><div>This study first proposes a mixed-integer linear programming model for the qualitative flexible multi-criteria method (QUALIFLEX) within an interval type-2 fuzzy environment. This extends an efficient QUALIFLEX method that already exists in the literature. The computational complexity of QUALIFLEX grows exponentially with an increase in the number of alternatives, and the extended model efficiently solves a multi-criteria decision problem and determines the best permutation regardless of the number of alternatives. A new QUALIFLEX algorithm is also developed to handle imprecise and conflicting preference structures for criteria weights. This algorithm includes both a single-objective and a bi-objective model to address incomplete and conflicting weight information, respectively, and these models are subsequently linearized. The newly developed algorithm solves the models only once to produce the best permutation and the corresponding weights, rather than requiring the solution of<span><math><mrow><mspace></mspace><mi>m</mi><mo>!</mo><mspace></mspace></mrow></math></span>nonlinear models as in previous studies. The implications of the proposed extended and developed algorithms are illustrated using numerical examples, and their performance is analyzed against existing methods across a set of 30 problems with varying numbers of alternatives. The formulated model achieves similar results to the previous version with a limited number of alternatives using only one model-solving attempt and demonstrates superior performance in terms of computation time for problems with a larger number of alternatives.</div></div>","PeriodicalId":10542,"journal":{"name":"Computers & Operations Research","volume":"176 ","pages":"Article 106951"},"PeriodicalIF":4.1,"publicationDate":"2024-12-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143165820","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Perishable inventory control with backlogging penalties: A mixed-integer linear programming model via two-step approximation

IF 4.1 2区工程技术

Computers & Operations Research Pub Date : 2024-12-17 DOI: 10.1016/j.cor.2024.106953

Yulun Wu , Shunji Tanaka

引用次数: 0

Mathematical modeling and hybrid evolutionary algorithm to schedule flexible job shop with discrete operation sequence flexibility

IF 4.1 2区工程技术

Computers & Operations Research Pub Date : 2024-12-17 DOI: 10.1016/j.cor.2024.106952

Shuai Yuan , Xiaomin Zhu , Wei Cai , Jinsheng Gao , Runtong Zhang

{"title":"Mathematical modeling and hybrid evolutionary algorithm to schedule flexible job shop with discrete operation sequence flexibility","authors":"Shuai Yuan , Xiaomin Zhu , Wei Cai , Jinsheng Gao , Runtong Zhang","doi":"10.1016/j.cor.2024.106952","DOIUrl":"10.1016/j.cor.2024.106952","url":null,"abstract":"<div><div>In actual industrial production, several operations of a job may not have precedence relationships and can be placed at any point in the process route. However, traditional flexible job shop scheduling problems (FJSP) often assume that all operations of each job must be processed in strict linear order. Therefore, this research addresses the FJSP with discrete operation sequence flexibility (FJSPDS) with the objective of minimizing the makespan. Based on existing models, two novel mixed-integer linear programming (MILP) models are formulated by improving the description methods of variables and constraints, significantly enhancing the models’ performance. Additionally, a hybrid evolutionary algorithm (HEA) is proposed to solve large-scale instances through the following three aspects. An improved encoding method is proposed, which makes the search space of the HEA and solution space of the problem more compatible and reduces the possibility of optimal solutions being missed. A special neighborhood structure is designed according to the characters of sequence-free operations, and an iterative local search method is introduced to improve the quality of the solution. A knowledge-driven reinitialization operator is developed, which generates new individuals based on the features of the historical elite population, guiding the evolution of populations, avoiding premature convergence while also avoiding falling into local optima. Finally, a total of 110 benchmark problem instances are utilized to verify the superior effectiveness of the MILP models and the HEA in solving FJSPDS.</div></div>","PeriodicalId":10542,"journal":{"name":"Computers & Operations Research","volume":"176 ","pages":"Article 106952"},"PeriodicalIF":4.1,"publicationDate":"2024-12-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143165822","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Sequencing and scheduling appointments with weighted completion time minimization and waiting time tolerance

IF 4.1 2区工程技术

Computers & Operations Research Pub Date : 2024-12-14 DOI: 10.1016/j.cor.2024.106948

Shenghai Zhou , Shuo Pang , Yunning Zhao , Yunting Shi

{"title":"Sequencing and scheduling appointments with weighted completion time minimization and waiting time tolerance","authors":"Shenghai Zhou , Shuo Pang , Yunning Zhao , Yunting Shi","doi":"10.1016/j.cor.2024.106948","DOIUrl":"10.1016/j.cor.2024.106948","url":null,"abstract":"<div><div>This paper investigates a sequencing and scheduling problem incorporating waiting time tolerance. The objective is to determine an arrival time for each appointment to minimize the sum of weighted expected completion times of all appointments, while ensuring compliance with waiting time limits for each appointment. Firstly, we derive the optimal schedule given any predetermined sequence. Secondly, we establish the optimal sequence solution for a special case. Thirdly, we introduce a sequencing solution derived from an alternative problem. We prove that this solution results in at most twice the optimal objective value under a mild condition. The experimental results indicate that the proposed method exhibits strong performance across a variety of settings. In addition, our numerical study reveals that the optimal schedule follows a distinctive ”dome” shape structure when service durations are independent and identically distributed (i.i.d.). We observe that a larger threshold for the waiting time target corresponds to smaller optimal job allowances, reduced gaps between optimal job allowances and mean service durations, and increased gaps between completion time and cumulative optimal job allowances. Furthermore, our results indicate that patient no-shows contribute to greater variability in waiting and idle times, along with reduced job allowances. These findings offer valuable theoretical and practical insights into appointment scheduling problems with waiting time tolerance.</div></div>","PeriodicalId":10542,"journal":{"name":"Computers & Operations Research","volume":"176 ","pages":"Article 106948"},"PeriodicalIF":4.1,"publicationDate":"2024-12-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143165832","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Cruise onboard itinerary planning for multi passengers with service venue capacity and time-window constraints

IF 4.1 2区工程技术

Computers & Operations Research Pub Date : 2024-12-14 DOI: 10.1016/j.cor.2024.106944

Jinghua Li , Zixiang Zhang , Dening Song , Boxin Yang , Lei Zhou

{"title":"Cruise onboard itinerary planning for multi passengers with service venue capacity and time-window constraints","authors":"Jinghua Li , Zixiang Zhang , Dening Song , Boxin Yang , Lei Zhou","doi":"10.1016/j.cor.2024.106944","DOIUrl":"10.1016/j.cor.2024.106944","url":null,"abstract":"<div><div>The design of personalized onboard itineraries for multiple cruise passengers plays an important role in improving the tourism experience on cruise. Different from itinerary planning for city traveling, the venues on cruise suffer from strict capacity and time-window constraints due to the safety requirements, which results in the coupling effects between itineraries of multiple passengers. This study constructs an optimization model to balancing the gap between passengers while maximizing passenger benefits, develops an Adaptive Large Neighborhood Search algorithm based on Improved destruction-repair operators (IOALNS) to solve multi-passenger itinerary planning. Extensive analyses are performed to demonstrate the performance advantages of the IOALNS algorithm in solving instances with varying sizes. Finally, the test results of cruise passenger instances show that compared with existing multi-passenger travel planning algorithms, the proposed algorithm can improve passenger efficiency by at least 9.98% and reduce computation time by more than 50%. These effectively improve passenger satisfaction and operational efficiency in the cruise industry.</div></div>","PeriodicalId":10542,"journal":{"name":"Computers & Operations Research","volume":"176 ","pages":"Article 106944"},"PeriodicalIF":4.1,"publicationDate":"2024-12-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143165823","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

A model-based algorithm for the Probabilistic Orienteering Problem

IF 4.1 2区工程技术

Computers & Operations Research Pub Date : 2024-12-13 DOI: 10.1016/j.cor.2024.106947

Roberto Montemanni , Derek H. Smith

引用次数: 0