Journal of Combinatorial Optimization最新文献_第10页

On list (p, 1)-total labellings of special planar graphs and 1-planar graphs 关于特殊平面图形和 1-planar 图形的列表 (p, 1)- 总标注

IF 1 4区数学

Journal of Combinatorial Optimization Pub Date : 2024-03-13 DOI: 10.1007/s10878-024-01111-3

Lin Sun, Guanglong Yu, Jianliang Wu

{"title":"On list (p, 1)-total labellings of special planar graphs and 1-planar graphs","authors":"Lin Sun, Guanglong Yu, Jianliang Wu","doi":"10.1007/s10878-024-01111-3","DOIUrl":"https://doi.org/10.1007/s10878-024-01111-3","url":null,"abstract":"A (p, 1)-total labelling of a graph G is a mapping f: (V(G)cup E(G)) (rightarrow ) ({0, 1, cdots , k}) such that (|f(u)-f(v)|ge 1) if (uvin E(G)), (|f(e_1)-f(e_2)|ge 1) if (e_1) and (e_2) are two adjacent edges in G and (|f(u)-f(e)|ge p) if the vertex u is incident with the edge e. In this paper, we focus on the list version of a (p, 1)-total labelling. Given a family (L={L(u)subseteq mathbb {N}:uin V(G)cup E(G)}), an L-list (p, 1)-total labelling of G is a (p, 1)-total labelling f of G such that (f(u)in L(u)) for every element (uin V(G)cup E(G)). A graph G is said to be (p, 1)-k-total choosable if it admits an L-list (p, 1)-total labelling whenever the family L contains only sets of size at least k. The smallest k for which a graph G is (p, 1)-k-total choosable is the list (p, 1)-total labelling number of G, denoted by (lambda _{lp}^T(G)). In this paper, we firstly use some important theorems related to Combinatorial Nullstellensatz to prove that the upper bound of (lambda _{lp}^T(C_n)) for cycles (C_n) is (2p+1) with (pge 2). Let G be a graph with maximum degree (Delta (G)ge 6p+3). Then we prove that if G is a planar graph or a 1-planar graph without adjacent 3-cycles, then (lambda _{lp}^T(G)le Delta (G)+2p-1) ((pge 2)).","PeriodicalId":50231,"journal":{"name":"Journal of Combinatorial Optimization","volume":"2 1","pages":""},"PeriodicalIF":1.0,"publicationDate":"2024-03-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140115781","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}

引用次数: 0

A linear ordering problem with weighted rank 加权秩的线性排序问题

IF 1 4区数学

Journal of Combinatorial Optimization Pub Date : 2024-02-26 DOI: 10.1007/s10878-024-01109-x

Manuel V. C. Vieira

引用次数: 0

Approximation algorithms for the fault-tolerant facility location problem with submodular penalties 具有亚模态惩罚的容错设施位置问题的近似计算算法

IF 1 4区数学

Journal of Combinatorial Optimization Pub Date : 2024-02-26 DOI: 10.1007/s10878-024-01106-0

Yingying Guo, Qiaoliang Li

引用次数: 0

On scheduling multiple parallel two-stage flowshops with Johnson’s Rule 用约翰逊法则调度多个并行两级流程车间

IF 1 4区数学

Journal of Combinatorial Optimization Pub Date : 2024-02-23 DOI: 10.1007/s10878-024-01107-z

Guangwei Wu, Fu Zuo, Feng Shi, Jianxin Wang

引用次数: 0

On sufficient conditions for Hamiltonicity of graphs, and beyond 论图的哈密顿性及其他的充分条件

IF 1 4区数学

Journal of Combinatorial Optimization Pub Date : 2024-02-23 DOI: 10.1007/s10878-024-01110-4

Hechao Liu, Lihua You, Yufei Huang, Zenan Du

引用次数: 0

EPTAS for parallel identical machine scheduling with time restrictions 用于有时间限制的并行相同机器调度的 EPTAS

IF 1 4区数学

Journal of Combinatorial Optimization Pub Date : 2024-02-22 DOI: 10.1007/s10878-024-01108-y

G. Jaykrishnan, Asaf Levin

引用次数: 0

On convexity in split graphs: complexity of Steiner tree and domination 论分裂图中的凸性：斯坦纳树和支配的复杂性

IF 1 4区数学

Journal of Combinatorial Optimization Pub Date : 2024-02-12 DOI: 10.1007/s10878-024-01105-1

A. Mohanapriya, P. Renjith, N. Sadagopan

{"title":"On convexity in split graphs: complexity of Steiner tree and domination","authors":"A. Mohanapriya, P. Renjith, N. Sadagopan","doi":"10.1007/s10878-024-01105-1","DOIUrl":"https://doi.org/10.1007/s10878-024-01105-1","url":null,"abstract":"Given a graph G with a terminal set (R subseteq V(G)), the Steiner tree problem (STREE) asks for a set (Ssubseteq V(G) {setminus } R) such that the graph induced on (Scup R) is connected. A split graph is a graph which can be partitioned into a clique and an independent set. It is known that STREE is NP-complete on split graphs White et al. (Networks 15(1):109–124, 1985). To strengthen this result, we introduce convex ordering on one of the partitions (clique or independent set), and prove that STREE is polynomial-time solvable for tree-convex split graphs with convexity on clique (K), whereas STREE is NP-complete on tree-convex split graphs with convexity on independent set (I). We further strengthen our NP-complete result by establishing a dichotomy which says that for unary-tree-convex split graphs (path-convex split graphs), STREE is polynomial-time solvable, and NP-complete for binary-tree-convex split graphs (comb-convex split graphs). We also show that STREE is polynomial-time solvable for triad-convex split graphs with convexity on I, and circular-convex split graphs. Further, we show that STREE can be used as a framework for the dominating set problem (DS) on split graphs, and hence the classical complexity (P vs NPC) of STREE and DS is the same for all these subclasses of split graphs. Finally, from the parameterized perspective with solution size being the parameter, we show that the Steiner tree problem on split graphs is W[2]-hard, whereas when the parameter is treewidth, we show that the problem is fixed-parameter tractable, and if the parameter is the solution size and the maximum degree of I (d), then we show that the Steiner tree problem on split graphs has a kernel of size at most ((2d-1)k^{d-1}+k,~k=|S|).","PeriodicalId":50231,"journal":{"name":"Journal of Combinatorial Optimization","volume":"43 1","pages":""},"PeriodicalIF":1.0,"publicationDate":"2024-02-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139728123","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}

引用次数: 0

On the packing number of antibalanced signed simple planar graphs of negative girth at least 5 关于周长至少为负 5 的反平衡有符号简单平面图形的包装数

IF 1 4区数学

Journal of Combinatorial Optimization Pub Date : 2024-02-12 DOI: 10.1007/s10878-023-01103-9

Reza Naserasr, Weiqiang Yu

{"title":"On the packing number of antibalanced signed simple planar graphs of negative girth at least 5","authors":"Reza Naserasr, Weiqiang Yu","doi":"10.1007/s10878-023-01103-9","DOIUrl":"https://doi.org/10.1007/s10878-023-01103-9","url":null,"abstract":"The packing number of a signed graph ((G, sigma )), denoted (rho (G, sigma )), is the maximum number l of signatures (sigma _1, sigma _2,ldots , sigma _l) such that each (sigma _i) is switching equivalent to (sigma ) and the sets of negative edges (E^{-}_{sigma _i}) of ((G,sigma _i)) are pairwise disjoint. A signed graph packs if its packing number is equal to its negative girth. A reformulation of some well-known conjecture in extension of the 4-color theorem is that every antibalanced signed planar graph and every signed bipartite planar graph packs. On this class of signed planar graph the case when negative girth is 3 is equivalent to the 4-color theorem. For negative girth 4 and 5, based on the dual language of packing T-joins, a proof is claimed by B. Guenin in 2002, but never published. Based on this unpublished work, and using the language of packing T-joins, proofs for girth 6, 7, and 8 are published. We have recently provided a direct proof for girth 4 and in this work extend the technique to prove the case of girth 5.","PeriodicalId":50231,"journal":{"name":"Journal of Combinatorial Optimization","volume":"1 1","pages":""},"PeriodicalIF":1.0,"publicationDate":"2024-02-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139728193","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}

引用次数: 0

An extension of the Christofides heuristic for a single-depot multiple Hamiltonian path problem 克里斯托菲德斯启发式对单深度多哈密顿路径问题的扩展

IF 1 4区数学

Journal of Combinatorial Optimization Pub Date : 2024-02-12 DOI: 10.1007/s10878-023-01104-8

Jun Wu, Zhen Yang, Guiqing Zhang, Yongxi Cheng

引用次数: 0

Improved shuffled Frog leaping algorithm with unsupervised population partitioning strategies for complex optimization problems 针对复杂优化问题采用无监督种群划分策略的改进型洗牌蛙跳算法

IF 1 4区数学

Journal of Combinatorial Optimization Pub Date : 2024-02-11 DOI: 10.1007/s10878-023-01102-w

Shikha Mehta

{"title":"Improved shuffled Frog leaping algorithm with unsupervised population partitioning strategies for complex optimization problems","authors":"Shikha Mehta","doi":"10.1007/s10878-023-01102-w","DOIUrl":"https://doi.org/10.1007/s10878-023-01102-w","url":null,"abstract":"Shuffled Frog leaping algorithm (SFLA) is a multi population swarm intelligence algorithm which employs population partitioning techniques during the evolutionary stage. Methods adopted by SFLA for partitioning the population into memeplexes play a critical role in determining its ability to solve complex optimization problems. However, limited research is done in this direction. This work presents supervised machine learning based methods Spectral Partitioning (SCP), Agglomerative Partitioning (AGP) and Ward Hierarchical Partitioning (WHP) for distributing the solutions into memeplexes. The efficacy of variants of SFLA with these methods is assessed over CEC2015 Bound Constrained Single-Objective Computationally Expensive Numerical Optimisation problems. Analysis of results establishes that proposed SCP, AGP and WHP methods outperform Shuffled complex evolution (SCE) partitioning technique; Seed and distance based partitioning technique (SEED), Random partitioning (RAND) and Dynamic sub-swarm partitioning (DNS) for more than 10 functions. Time complexity of all the algorithms is comparable with each other. Statistical analysis using Wilcoxon signed rank sum test indicates that SCP, AGP and WHP perform significantly better than existing approaches for small dimensions.","PeriodicalId":50231,"journal":{"name":"Journal of Combinatorial Optimization","volume":"23 1","pages":""},"PeriodicalIF":1.0,"publicationDate":"2024-02-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139720282","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}

引用次数: 0