Journal of Combinatorial Optimization最新文献

{"title":"Chaotic guided local search algorithm for solving global optimization and engineering problems","authors":"Anis Naanaa","doi":"10.1007/s10878-025-01281-8","DOIUrl":"https://doi.org/10.1007/s10878-025-01281-8","url":null,"abstract":"<p>Chaos optimization algorithm (COA) is an interesting alternative in a global optimization problem. Due to the non-repetition and ergodicity of chaos, it can explore the global search space at higher speeds than stochastic searches that depend on probabilities. To adjust the solution obtained by COA, guided local search algorithm (GLS) is integrated with COA to form a hybrid algorithm. GLS is a metaheuristic optimization algorithm that combines elements of local search with strategic guidance to efficiently explore the solution space. This study proposes a chaotic guided local search algorithm to search for global solutions. The proposed algorithm, namely COA-GLS, contributes to optimization problems by providing a balance between quick convergence and good solution quality. Its combination of local refinement, strategic guidance, diversification strategies, and adaptability makes it a powerful metaheuristic capable of efficiently navigating complex solution spaces and finding high-quality solutions in a relatively short amount of time. Simulation results show that the present algorithms significantly outperform the existing methods in terms of convergence speed, numerical stability, and a better optimal solution than other algorithms.</p>","PeriodicalId":50231,"journal":{"name":"Journal of Combinatorial Optimization","volume":"53 1","pages":""},"PeriodicalIF":1.0,"publicationDate":"2025-04-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143876098","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A multi-objective perspective on the cable-trench problem","authors":"Lara Löhken, Michael Stiglmayr","doi":"10.1007/s10878-025-01289-0","DOIUrl":"https://doi.org/10.1007/s10878-025-01289-0","url":null,"abstract":"<p>The cable-trench problem is defined as a linear combination of the shortest path and the minimum spanning tree problem. In particular, the goal is to find a spanning tree that simultaneously minimizes its total length and the total path length from a pre-defined root to all other vertices. Both, the minimum spanning tree and the shortest path problem are known to be efficiently solvable. However, a linear combination of these two objectives results in a highly complex problem. In this article, we introduce the bi-objective cable-trench problem which separates the two cost functions. We show that in general, the bi-objective formulation has additional compromise solutions compared to the cable-trench problem in its original formulation. To determine the set of non-dominated points and efficient solutions, we use <span>(varepsilon )</span>-constraint scalarizations in combination with a problem-specific cutting plane. Moreover, we present numerical results on different types of graphs analyzing the impact of density and cost structure on the cardinality of the non-dominated set and the solution time.</p>","PeriodicalId":50231,"journal":{"name":"Journal of Combinatorial Optimization","volume":"35 1","pages":""},"PeriodicalIF":1.0,"publicationDate":"2025-04-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143876069","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Path survival reliabilities as measures of reliability for lifeline utility networks","authors":"Brian Godwin Lim, Renzo Roel Tan, Richard de Jesus, Lessandro Estelito Garciano, Agnes Garciano, Kazushi Ikeda","doi":"10.1007/s10878-025-01291-6","DOIUrl":"https://doi.org/10.1007/s10878-025-01291-6","url":null,"abstract":"<p>Lifeline utility networks have been studied extensively within the domain of network reliability due to the prevalence of natural hazards. The reliability of these networks is typically investigated through graphs that retain their structural characteristics. This paper introduces novel connectivity-based reliability measures tailored for stochastic graphs with designated source vertices and failure-probability-weighted edges. In particular, the per-vertex path survival reliability quantifies the average survival likelihood of single-source paths from a vertex to any source. A consolidated per-graph reliability measure is also presented, incorporating graph density and the shortest distance to a source as regulating elements for network comparison. To highlight the advantages of the proposed reliability measures, a theoretical discussion of their key properties is presented, along with a comparison against standard reliability measurements. The proposal is further accompanied by an efficient calculation procedure utilizing the zero-suppressed binary decision diagram, constructed through the frontier-based search, to compactly represent all single-source paths. Finally, the path survival reliabilities are calculated for a set of real-world networks and demonstrated to provide practical insights.\u0000</p>","PeriodicalId":50231,"journal":{"name":"Journal of Combinatorial Optimization","volume":"16 1","pages":""},"PeriodicalIF":1.0,"publicationDate":"2025-04-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143876097","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The two-center problem of uncertain points on cactus graphs","authors":"Haitao Xu, Jingru Zhang","doi":"10.1007/s10878-025-01292-5","DOIUrl":"https://doi.org/10.1007/s10878-025-01292-5","url":null,"abstract":"<p>We study the two-center problem on cactus graphs in facility locations, which aims to place two facilities on the graph network to serve customers in order to minimize the maximum transportation cost. In our problem, the location of each customer is uncertain and may appear at <i>O</i>(<i>m</i>) points on the network with probabilities. More specifically, given are a cactus graph <i>G</i> and a set <span>(mathcal {P})</span> of <i>n</i> (weighted) uncertain points where every uncertain point has <i>O</i>(<i>m</i>) possible locations on <i>G</i> each associated with a probability and is of a non-negative weight. The problem aims to compute two centers (points) on <i>G</i> so that the maximum (weighted) expected distance of the <i>n</i> uncertain points to their own expected closest center is minimized. No previous algorithms are known for this problem. In this paper, we present the first algorithm for this problem and it solves the problem in <span>(O(|G|+ m^{2}n^{2}log mn))</span> time.</p>","PeriodicalId":50231,"journal":{"name":"Journal of Combinatorial Optimization","volume":"64 1","pages":""},"PeriodicalIF":1.0,"publicationDate":"2025-04-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143857501","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"On the parenthesisations of matrix chains: All are useful, few are essential","authors":"Francisco López, Lars Karlsson, Paolo Bientinesi","doi":"10.1007/s10878-025-01290-7","DOIUrl":"https://doi.org/10.1007/s10878-025-01290-7","url":null,"abstract":"<p>The product of a matrix chain consisting of <i>n</i> matrices can be computed in <span>(C_{n-1})</span> (Catalan’s number) different ways, each identified by a distinct parenthesisation of the chain. The best algorithm to select a parenthesisation that minimises the cost runs in <span>(O(n log n))</span> time. Approximate algorithms run in <i>O</i>(<i>n</i>) time and find solutions that are guaranteed to be within a certain factor from optimal; the best factor is currently 1.155. In this article, we first prove two results that characterise different parenthesisations, and then use those results to improve on the best known approximation algorithms. Specifically, we show that (a) each parenthesisation is optimal somewhere in the problem domain, and (b) exactly <span>(n + 1)</span> parenthesisations are essential in the sense that the removal of any one of them causes an unbounded penalty for an infinite number of problem instances. By focusing on essential parenthesisations, we improve on the best known approximation algorithm and show that the approximation factor is at most 1.143.</p>","PeriodicalId":50231,"journal":{"name":"Journal of Combinatorial Optimization","volume":"60 1","pages":""},"PeriodicalIF":1.0,"publicationDate":"2025-04-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143832389","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Maximizing utilitarian and Egalitarian welfare of fractional hedonic games on tree-like graphs","authors":"Tesshu Hanaka, Airi Ikeyama, Hirotaka Ono","doi":"10.1007/s10878-025-01283-6","DOIUrl":"https://doi.org/10.1007/s10878-025-01283-6","url":null,"abstract":"<p>Fractional hedonic games are coalition formation games where a player’s utility is determined by the average value they assign to the members of their coalition. These games are a variation of graph hedonic games, which are a class of coalition formation games that can be succinctly represented. Due to their applicability in network clustering and their relationship to graph hedonic games, fractional hedonic games have been extensively studied from various perspectives. However, finding welfare-maximizing partitions in fractional hedonic games is a challenging task due to the nonlinearity of utilities. In fact, it has been proven to be NP-hard and can be solved in polynomial time only for a limited number of graph classes, such as trees. This paper presents (pseudo)polynomial-time algorithms to compute welfare-maximizing partitions in fractional hedonic games on tree-like graphs. We consider two types of social welfare measures: utilitarian and egalitarian. Tree-like graphs refer to graphs with bounded treewidth and block graphs. A hardness result is provided, demonstrating that the pseudopolynomial-time solvability is the best possible under the assumption P <span>(ne )</span> NP.</p>","PeriodicalId":50231,"journal":{"name":"Journal of Combinatorial Optimization","volume":"26 1","pages":""},"PeriodicalIF":1.0,"publicationDate":"2025-04-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143832390","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Testing Higher-order Clusterability on Graphs","authors":"Yifei Li, Donghua Yang, Jianzhong Li","doi":"10.1007/s10878-025-01262-x","DOIUrl":"https://doi.org/10.1007/s10878-025-01262-x","url":null,"abstract":"<p>Analysis of higher-order organizations, represented as small connected subgraphs, is a fundamental task on complex networks. This paper studies a new problem of testing higher-order clusterability: given neighbor query access to an undirected graph, can we judge whether this graph can be partitioned into a few clusters of highly-connected cliques? This problem is an extension of the former work proposed by Czumaj et al. (STOC’ 15), who recognized cluster structure on graphs using the framework of property testing. In this paper, the problem of testing whether a well-defined higher-order cluster exists is first defined. Then, an <span>(varOmega (sqrt{n}))</span> query lower bound of this problem is given. After that, a baseline algorithm is provided by an edge-cluster tester on <i>k</i>-clique dual graph. Finally, an optimized <span>(tilde{O}(sqrt{n}))</span>-time algorithm is developed for testing clusterability based on triangles.</p>","PeriodicalId":50231,"journal":{"name":"Journal of Combinatorial Optimization","volume":"27 1","pages":""},"PeriodicalIF":1.0,"publicationDate":"2025-04-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143824791","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Approximation algorithm for dynamic facility location problem","authors":"Li Zhang, Qiaoliang Li","doi":"10.1007/s10878-025-01282-7","DOIUrl":"https://doi.org/10.1007/s10878-025-01282-7","url":null,"abstract":"<p>In this paper, we consider dynamic facility location problem with unit demand (DFLPUD). We propose a 1.52-approximation algorithm that skillfully integrates dual-fitting and greedy augmentation schemes. Our algorithmic framework begins by formulating DFLPUD as a set covering linear integer programming problem. Then we scale the opening cost of all facilities and use the solution of dual-fitting algorithm to seed a local search to yield an improved performance guarantee 1.52. To the best of our knowledge, this is the best known approximation ratio for DFLPUD.</p>","PeriodicalId":50231,"journal":{"name":"Journal of Combinatorial Optimization","volume":"117 1","pages":""},"PeriodicalIF":1.0,"publicationDate":"2025-04-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143822885","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A sharp upper bound for the edge dominating number of hypergraphs with minimum degree","authors":"Zhongzheng Tang, Zhuo Diao","doi":"10.1007/s10878-025-01284-5","DOIUrl":"https://doi.org/10.1007/s10878-025-01284-5","url":null,"abstract":"<p>In a hypergraph <i>H</i>(<i>V</i>, <i>E</i>), a subset of edges <span>(Asubseteq E)</span> forms an edge dominating set if each edge <span>(ein Esetminus A)</span> is adjacent to at least one edge in <i>A</i>. The edge dominating number <span>(gamma '(H))</span> represents the smallest size of an edge dominating set in <i>H</i>. In this paper, we establish upper bounds on the edge dominating number for hypergraphs with minimum degree <span>(delta )</span>: (1) For <span>(delta le 4)</span>, <span>(gamma '(H)le frac{m}{delta })</span>; (2) For <span>(delta ge 5)</span>, <span>(gamma '(H)le frac{m}{delta })</span> holds for hypertrees and uniform hypergraphs; (3) For a random hypergraph model <span>(mathcal H(n,m))</span>, for any positive number <span>(varepsilon &gt;0)</span>, <span>(gamma ' (H)le (1+varepsilon )frac{m}{delta })</span> holds with high probability when <i>m</i> is bounded by some polynomial function of <i>n</i>. Based on the proofs, some combinatorial algorithms on the edge dominating number of hypergraphs with minimum degree are designed.</p>","PeriodicalId":50231,"journal":{"name":"Journal of Combinatorial Optimization","volume":"34 1","pages":""},"PeriodicalIF":1.0,"publicationDate":"2025-04-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143822881","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Link fault tolerability of the Cartesian product power graph $$(K_{9}-C_{9})^{n}$$ : conditional edge-connectivities under six link fault patterns","authors":"Zhaoman Huang, Yayu Yang, Mingzu Zhang, Weihua Yang","doi":"10.1007/s10878-025-01273-8","DOIUrl":"https://doi.org/10.1007/s10878-025-01273-8","url":null,"abstract":"<p>High-performance computing extensively depends on parallel and distributed systems, necessitating the establishment of quantitative parameters to evaluate the fault tolerability of interconnection networks. The topological structures of interconnection networks in some parallel and distributed systems are designed as <i>n</i>-dimensional <span>((K_{9}-C_{9})^{n})</span>, obtained through the repeatedly application of the <i>n</i>-th Cartesian product operation. Since the <span>(mathcal {P})</span>-conditional edge-connectivity is proposed by Harary, as a parameter for evaluating the link fault tolerability of the underlying topology graph of the interconnection network system, it has been widely studied in many interconnection networks. The <span>(mathcal {P})</span>-conditional edge-connectivity of a connected graph <i>G</i>, denoted by <span>(lambda (mathcal {P};G))</span>, if any, describes the minimum cardinality of the fault edge-cut of the graph <i>G</i>, whose malfunction divides <i>G</i> into multiple components, with each component satisfying a given property <span>(mathcal {P})</span> of the graph. In this paper, we primarily define <span>(mathcal {P}_{i}^{t})</span> to be properties of containing at least <span>(9^t)</span> processors, every remaining processor lying in a lower dimensional subnetwork of the <span>((K_{9}-C_{9})^{n})</span>, <span>((K_{9}-C_{9})^{t})</span>, having a minimum degree or average degree of at least 6<i>t</i>, existing two components with each component having at least <span>(9^t)</span> processors, and containing at least one cycle, respectively. We use the properties of the optimal solution to the edge isoperimetric problem of <span>((K_{9}-C_{9})^{n})</span> and find that the exact values of the <span>(mathcal {P}_{i})</span>-conditional edge-connectivities of the graph <span>((K_{9}-C_{9})^{n})</span> share a common value of <span>(6(n-t)9^t)</span> for <span>(1le ile 5)</span> and <span>(0le tle n-1)</span>, except for <span>(i=6)</span>, the value is <span>(18n - 6)</span>.</p>","PeriodicalId":50231,"journal":{"name":"Journal of Combinatorial Optimization","volume":"66 1","pages":""},"PeriodicalIF":1.0,"publicationDate":"2025-04-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143822884","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}