International Transactions in Operational Research最新文献

{"title":"Quantity leadership in dual-channel supply chains with production economies or diseconomies","authors":"Jinru Feng,&nbsp;Wei Li,&nbsp;Jing Chen","doi":"10.1111/itor.70187","DOIUrl":"https://doi.org/10.1111/itor.70187","url":null,"abstract":"<p>This study examines a dual-channel supply chain in which a manufacturer sells products through both a downstream retailer and its own direct channel. The manufacturer first sets the wholesale price, after which the two firms engage in one of three quantity competition games: a simultaneous-move game, a manufacturer-as-leader game, or a retailer-as-leader game. We investigate how production economies or diseconomies of scale influence the quantity leadership and followership decisions of supply chain parties. We find that stronger economies of scale may hurt both the manufacturer and the retailer, while stronger diseconomies of scale can improve profitability for both parties. The quantity leadership structure plays a critical mediating role in these effects. We also show that a retailer leadership equilibrium emerges endogenously when diseconomies of scale are present or when the level of economies of scale is sufficiently low, whereas a manufacturer leadership equilibrium prevails when the level of economies of scale is high. Furthermore, we show that endogenous leadership choices, particularly when the manufacturer becomes the leader, can reduce consumer surplus and social welfare. These findings offer managerial implications for strategic decisions in dual-channel supply chain management.</p>","PeriodicalId":49176,"journal":{"name":"International Transactions in Operational Research","volume":"33 6","pages":"3975-4004"},"PeriodicalIF":2.9,"publicationDate":"2026-06-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148193970","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"管理学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A genetic algorithm simheuristic for solving the stochastic project portfolio selection problem with portfolio reliability constraints","authors":"Miguel Saiz,&nbsp;David Lopez-Lopez,&nbsp;Laura Calvet,&nbsp;Angel A. Juan","doi":"10.1111/itor.70064","DOIUrl":"https://doi.org/10.1111/itor.70064","url":null,"abstract":"<p>In response to the increasing complexity of modern products, dynamic markets, and intensified competition, project-based organizations are actively seeking methodologies to efficiently manage their expanding project portfolios. This paper analyzes the project portfolio selection problem in uncertain environments. Despite recent advances in the field, there is a pressing need for decision-making frameworks that blend optimization and simulation with realistic project information and portfolio constraints. Through an extensive literature review, we identify key variables critical for handling practical scenarios, such as project schedule interdependencies, duration estimations across various scenarios, baseline budget, risk registers, interproject correlations, and cost overrun correlation. To tackle the inherent stochasticity, we introduce a simheuristic algorithm that combines genetic optimization with Monte Carlo simulation. This strategy maximizes the expected value while adhering to project and portfolio constraints under a set portfolio budget reliability level. This approach provides decision-makers with a powerful tool for enhancing project selection processes, promoting upfront planning, improving risk management, and the achievement of strategic goals. The performance of this approach is validated against deterministic methodologies, such as employing a mixed-integer linear programming solver in stochastic environments, demonstrating its effectiveness and practical applicability.</p>","PeriodicalId":49176,"journal":{"name":"International Transactions in Operational Research","volume":"33 6","pages":"4039-4071"},"PeriodicalIF":2.9,"publicationDate":"2026-06-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1111/itor.70064","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148194088","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"管理学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Information sharing and channel selection when considering live streaming commerce","authors":"Wenhui Zhou,&nbsp;Chao Wu,&nbsp;Hongmei Yang","doi":"10.1111/itor.70111","DOIUrl":"https://doi.org/10.1111/itor.70111","url":null,"abstract":"<p>With the rise of e-commerce, some manufacturers tend to establish multiple distribution channels consisting of direct and livestream to earn additional revenue. To counteract manufacturers' distribution strategies, the retailers with private demand information often adopt the information sharing strategy. In our research, we construct a game-theoretic model to investigate how information-sharing decisions of retailers and distribution channel selections of manufacturers affect the supply chain. We consider the above procedure in two leadership scenarios: the manufacturer led and the retailer led. Our research fully characterizes the equilibrium outcomes and shows how they are affected by variables such as channel substitutability, key opinion leaders (KOL) commission rate, and network externality. We find that only under the retailer-led scenario will the retailer choose to share demand information, which indicates the choice of leader has a major impact on each party's strategy. Our studies also unfold that the network externality may hurt the manufacturer when opening the livestream channel and the KOL charges a high commission fee. The manufacturer will decrease the wholesale price to boost wholesale sales, which is called the “bailout effect.” Therefore, we advise that the managers should focus more on the wholesale channel sometimes.</p>","PeriodicalId":49176,"journal":{"name":"International Transactions in Operational Research","volume":"33 6","pages":"4167-4194"},"PeriodicalIF":2.9,"publicationDate":"2026-06-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148194205","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"管理学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The impact of public drop-off boxes and autonomous delivery robots in last-mile delivery","authors":"Gianpaolo Ghiani,&nbsp;Emanuela Guerriero,&nbsp;Emanuele Manni,&nbsp;Deborah Pareo","doi":"10.1111/itor.70169","DOIUrl":"https://doi.org/10.1111/itor.70169","url":null,"abstract":"<p>The growing concern over emissions from last-mile logistics is motivating the development of innovative delivery models aimed at reducing environmental impact and traffic congestion. To this end, we propose a last-mile delivery scheme based on both public drop-off boxes and autonomous delivery robots. Unlike current practices, we assume that parcels are primarily delivered by a fleet of traditional vehicles to a number of drop-off boxes owned by the municipalities and shared by several logistics providers. Then, citizens must autonomously reach the drop-off point to retrieve their parcels. An exception is made for a small group of customers (like, for instance, elderly or disabled people) whose parcels are loaded on autonomous delivery robots and home-delivered, starting from the drop-off points. To tackle this problem, we devise tailored destroy-and-repair operators to be embedded into a neighborhood-search framework. We then conduct an extensive computational study on a set of realistic instances based on the urban area of Rome (Italy), aimed at assessing the benefits of the proposed last-mile delivery infrastructure, compared to traditional distribution methods. Additionally, we evaluate the environmental and economic advantages of using autonomous delivery robots and drop-off points.</p>","PeriodicalId":49176,"journal":{"name":"International Transactions in Operational Research","volume":"33 6","pages":"3825-3854"},"PeriodicalIF":2.9,"publicationDate":"2026-06-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1111/itor.70169","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148194012","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"管理学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A computational evaluation of new and existing dispatching rules for the single machine total weighted tardiness problem","authors":"Ana Sofia M. Martins,&nbsp;Jorge M. S. Valente,&nbsp;Jeffrey E. Schaller","doi":"10.1111/itor.70146","DOIUrl":"https://doi.org/10.1111/itor.70146","url":null,"abstract":"<p>This paper considers the single machine total weighted tardiness problem. A thorough computational evaluation of new and existing dispatching rules is performed. We considered several existing heuristics and proposed new backward rules. These procedures are analyzed together for the first time and coded in the same programming language. We also created a new and much larger dataset, which allows a more detailed comparison and provides a useful benchmark for future work.</p><p>We first conducted preliminary tests to determine appropriate parameter values and to choose between three versions of the new rules. These tests showed a need to use instance characteristics to make better choices. We then analyzed the heuristics and identified the non-dominated procedures, considering solution quality and computational time. One of the new backward rules is non-dominated, achieving the best solution quality. The non-dominated set allows decision-makers to choose a procedure depending on problem size and available time.</p>","PeriodicalId":49176,"journal":{"name":"International Transactions in Operational Research","volume":"33 6","pages":"3882-3904"},"PeriodicalIF":2.9,"publicationDate":"2026-06-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148193922","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"管理学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Optimal blockchain adoption and financing strategies in an outsourcing remanufacturing supply chain","authors":"Peng Ma,&nbsp;Jingwen Li,&nbsp;Junmei Li,&nbsp;Yuzhuo Qiu,&nbsp;Henry Xu","doi":"10.1111/itor.70181","DOIUrl":"https://doi.org/10.1111/itor.70181","url":null,"abstract":"<p>Outsourcing remanufacturing is an environmentally friendly production method and has been widely studied. Because consumers lack trust in the quality of remanufactured products (RPs), introducing blockchain technology (BT) into the remanufacturing channel can alleviate consumers’ distrust about the quality of RPs. Considering that the third-party remanufacturer (TPR) may have insufficient initial capital, this paper focuses on investigating the TPR's optimal blockchain adoption strategies and financing options. We have the following main findings: (i) Consumers’ high preference for RPs can motivate the TPR to opt for a trade credit, while high financing rates can increase the possibility of the TPR's choice of a bank credit; (ii) the TPR adopts the BT only when the blockchain usage is cheap or the consumers are highly sensitive for BT; (iii) the cost and revenue-sharing contracts in the supply chains may lead to higher profits both for the OEM and the TPR.</p>","PeriodicalId":49176,"journal":{"name":"International Transactions in Operational Research","volume":"33 6","pages":"4005-4038"},"PeriodicalIF":2.9,"publicationDate":"2026-06-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148194032","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"管理学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Offering indoor trade-in? Optimal “one-stop” trade-in service strategy","authors":"Jinyuan Ma,&nbsp;Kaiying Cao","doi":"10.1111/itor.70071","DOIUrl":"https://doi.org/10.1111/itor.70071","url":null,"abstract":"<p>In recent years, some firms have introduced “one-stop” trade-in services, where consumers receive the new product after participating in the activity and return the old one to the service provider at home. To examine whethh firms’ decisions on offering “one-stop” trade-in services, we develop theoretical models involving a brand firm and a retailer. The results show that the brand firm should not provide the “one-stop” trade-in service when the new product scheduling cost in the “one-stop” trade-in service is relatively high. Otherwise, the brand firm should (not) provide the “one-stop” trade-in service if the fixed cost of implementing the “one-stop” trade-in service is relatively low (high). Furthermore, the brand firm is more willing to provide a “one-stop” service under a decentralized system than a centralized one. In the extensions, we consider the two-part tariff contract, the impact of online reviews and the differences in consumer satisfaction with the final trade-in rebate, and find that the main conclusions remain solid.</p>","PeriodicalId":49176,"journal":{"name":"International Transactions in Operational Research","volume":"33 6","pages":"3934-3974"},"PeriodicalIF":2.9,"publicationDate":"2026-06-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148194147","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"管理学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"State-dependent machine availability in scheduling","authors":"Antonia Arter,&nbsp;Dirk Briskorn,&nbsp;Andreas Hipp,&nbsp;Florian Jaehn","doi":"10.1111/itor.70183","DOIUrl":"https://doi.org/10.1111/itor.70183","url":null,"abstract":"<p>This paper addresses the field of scheduling problems with machine availability constraints. We give a systematic overview of models that cover any type of state-dependent machine availability restriction caused by jobs or machines. This type of availability constraint has received more attention in recent Operations Research studies because it can be found in various real-world settings. In these settings, the machine state is defined not only by the machine's continuous utilization time but also by other aspects related to machine availability. For instance, the job position in the production sequence on a given machine can have an effect on processing times, deterioration levels of machines, or the length of maintenance operations. Since, to the best of our knowledge, there is no existing systematic survey, we outline the characteristics and demarcate this type of machine availability from the mass of adjacent research. Furthermore, we present and categorize relevant literature dealing with each type of state-dependent machine availability and discuss the relationships between these categories.</p>","PeriodicalId":49176,"journal":{"name":"International Transactions in Operational Research","volume":"33 6","pages":"3769-3799"},"PeriodicalIF":2.9,"publicationDate":"2026-06-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148194154","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"管理学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Ensuring connectedness for the maximum quasi-clique and densest k-subgraph problems","authors":"Daniela Scherer dos Santos,&nbsp;Kathrin Klamroth,&nbsp;Pedro Martins,&nbsp;Luís Paquete","doi":"10.1111/itor.70184","DOIUrl":"https://doi.org/10.1111/itor.70184","url":null,"abstract":"<p>Given an undirected graph <span></span><math>\u0000 <semantics>\u0000 <mi>G</mi>\u0000 <annotation>$G$</annotation>\u0000 </semantics></math>, a quasi-clique is a subgraph of <span></span><math>\u0000 <semantics>\u0000 <mi>G</mi>\u0000 <annotation>$G$</annotation>\u0000 </semantics></math> with density at least <span></span><math>\u0000 <semantics>\u0000 <mi>γ</mi>\u0000 <annotation>$gamma$</annotation>\u0000 </semantics></math> <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <mo>(</mo>\u0000 <mn>0</mn>\u0000 <mo>&lt;</mo>\u0000 <mi>γ</mi>\u0000 <mo>≤</mo>\u0000 <mn>1</mn>\u0000 <mo>)</mo>\u0000 </mrow>\u0000 <annotation>$(0 &lt; gamma le 1)$</annotation>\u0000 </semantics></math>. Two optimisation problems can be defined for quasi-cliques: the maximum quasi-clique (MQC) problem, which finds a quasi-clique with maximum vertex cardinality, and the densest <span></span><math>\u0000 <semantics>\u0000 <mi>k</mi>\u0000 <annotation>$k$</annotation>\u0000 </semantics></math>-subgraph (DKS) problem, which finds the densest subgraph of a given fixed cardinality. Most existing approaches to solving both problems often disregard the requirement of connectedness, leading to unconnected solutions that may be meaningless for many real-life applications. To address this issue, we propose two flow-based and an Miller–Tucher–Zemlin-based connectedness constraint for integration into existing mixed-integer linear programming (MILP) formulations for MQC and DKS. We compare MILP formulations enhanced with our connectedness constraints in terms of both running time and number of solved instances against existing approaches that ensure quasi-clique connectedness. Experimental results demonstrate that our constraints are competitive, making them valuable for practical applications requiring connectedness.</p>","PeriodicalId":49176,"journal":{"name":"International Transactions in Operational Research","volume":"33 6","pages":"3800-3824"},"PeriodicalIF":2.9,"publicationDate":"2026-06-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1111/itor.70184","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148193899","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"管理学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Collaborative delivery problem of trucks and multiple drones: an en-route operation with flexible launch positions","authors":"Bing Han,&nbsp;TianZe Chi,&nbsp;Zhengyi Sun","doi":"10.1111/itor.70045","DOIUrl":"https://doi.org/10.1111/itor.70045","url":null,"abstract":"<p>Drones are gradually being used in logistics, and collaborative systems combining trucks and drones are proposed for last-mile delivery. Therefore, it is a meaningful study to improve the efficiency of collaborative delivery of truck–drone system. Based on the truck–drone collaborative delivery problem with en-route operations, this paper introduces a new concept of flexible launch point, which is to set up multiple non-customer stops in the truck's route for launching drones. In light of this concept, an en-route operation with flexible positions in the truck–drone collaborative delivery problem is proposed. The problem is formulated as a mixed integer linear program that aims to minimize customer waiting times, determine the optimal route for the truck with multi-drones, and establish the optimal flexible launch positions for the drones. We developed a variable neighborhood search algorithm and conducted large-scale experiments. The experiments have demonstrated that the new collaborative approach maximizes drone utilization, expands the range of drone services, and ensures flexible launch. The en-route operation with flexible launch positions presented in this paper provides innovative ideas for further application of trucks with multi-drones in last-mile delivery. This is also relevant for other scenarios, such as emergency management and routine inspections, which involve collaboration between trucks and drones.</p>","PeriodicalId":49176,"journal":{"name":"International Transactions in Operational Research","volume":"33 6","pages":"4072-4109"},"PeriodicalIF":2.9,"publicationDate":"2026-06-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148194099","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"管理学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}