Journal of Combinatorial Optimization最新文献_第10页

Proper colorability of segment intersection graphs 线段交叉图的适当着色

IF 1 4区数学

Journal of Combinatorial Optimization Pub Date : 2024-05-05 DOI: 10.1007/s10878-024-01149-3

Robert D. Barish, Tetsuo Shibuya

{"title":"Proper colorability of segment intersection graphs","authors":"Robert D. Barish, Tetsuo Shibuya","doi":"10.1007/s10878-024-01149-3","DOIUrl":"https://doi.org/10.1007/s10878-024-01149-3","url":null,"abstract":"We consider the vertex proper coloring problem for highly restricted instances of geometric intersection graphs of line segments embedded in the plane. Provided a graph in the class UNIT-PURE-k-DIR, corresponding to intersection graphs of unit length segments lying in at most k directions with all parallel segments disjoint, and provided explicit coordinates for segments whose intersections induce the graph, we show for (k = 4) that it is NP-complete to decide if a proper 3-coloring exists, and moreover, (#P)-complete under many-one counting reductions to determine the number of such colorings. In addition, under the more relaxed constraint that segments have at most two distinct lengths, we show these same hardness results hold for finding and counting proper (left( k-1right) )-colorings for every (k ge 5). More generally, we establish that the problem of proper 3-coloring an arbitrary graph with m edges can be reduced in ({mathcal {O}}left( m^2right) ) time to the problem of proper 3-coloring a UNIT-PURE-4-DIR graph. This can then be shown to imply that no (2^{oleft( sqrt{n}right) }) time algorithm can exist for proper 3-coloring PURE-4-DIR graphs under the Exponential Time Hypothesis (ETH), and by a slightly more elaborate construction, that no (2^{oleft( sqrt{n}right) }) time algorithm can exist for counting the such colorings under the Counting Exponential Time Hypothesis (#ETH). Finally, we prove an NP-hardness result for the optimization problem of finding a maximum order proper 3-colorable induced subgraph of a UNIT-PURE-4-DIR graph.\u0000","PeriodicalId":50231,"journal":{"name":"Journal of Combinatorial Optimization","volume":"56 1","pages":""},"PeriodicalIF":1.0,"publicationDate":"2024-05-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140845654","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

The doubly metric dimensions of cactus graphs and block graphs 仙人掌图和块状图的双重度量维数

IF 1 4区数学

Journal of Combinatorial Optimization Pub Date : 2024-05-05 DOI: 10.1007/s10878-024-01168-0

Kairui Nie, Kexiang Xu

引用次数: 0

Verifying the first nonzero term: physical ZKPs for ABC End View, Goishi Hiroi, and Toichika 验证第一个非零项：ABC 的物理 ZKPs End View、Goishi Hiroi 和 Toichika

IF 1 4区数学

Journal of Combinatorial Optimization Pub Date : 2024-05-05 DOI: 10.1007/s10878-024-01170-6

Suthee Ruangwises

引用次数: 0

Planar graphs are acyclically edge $$(Delta + 5)$$ -colorable 平面图具有非循环边$$(Delta + 5)$$ -可着色性

IF 1 4区数学

Journal of Combinatorial Optimization Pub Date : 2024-04-27 DOI: 10.1007/s10878-024-01165-3

Qiaojun Shu, Guohui Lin

引用次数: 0

Hybrid optimized deep recurrent neural network for atmospheric and oceanic parameters prediction by feature fusion and data augmentation model 通过特征融合和数据增强模型预测大气和海洋参数的混合优化深度递归神经网络

IF 1 4区数学

Journal of Combinatorial Optimization Pub Date : 2024-04-27 DOI: 10.1007/s10878-024-01159-1

Sundeep Raj, Sandesh Tripathi, K. C. Tripathi, Rajendra Kumar Bharti

{"title":"Hybrid optimized deep recurrent neural network for atmospheric and oceanic parameters prediction by feature fusion and data augmentation model","authors":"Sundeep Raj, Sandesh Tripathi, K. C. Tripathi, Rajendra Kumar Bharti","doi":"10.1007/s10878-024-01159-1","DOIUrl":"https://doi.org/10.1007/s10878-024-01159-1","url":null,"abstract":"In recent years climate prediction has obtained more attention to mitigate the impact of natural disasters caused by climatic variability. Efficient and effective climate prediction helps palliate negative consequences and allows favourable conditions for managing the resources optimally through proper planning. Due to the environmental, geopolitical and economic consequences, forecasting of atmospheric and oceanic parameters still results in a challenging task. An efficient prediction technique named Sea Lion Autoregressive Deer Hunting Optimization-based Deep Recurrent Neural Network (SLArDHO-based Deep RNN) is developed in this research to predict the oceanic and atmospheric parameters. The extraction of technical indicators makes the devised method create optimal and accurate prediction outcomes by employing the deep learning framework. The classifier uses more training samples and this can be generated by augmenting the data samples using the oversampling method. The atmospheric and the oceanic parameters are considered for the prediction strategy using the Deep RNN classifier. Here, the weights of the Deep RNN classifier are optimally tuned by the SLArDHO algorithm to find the best value based on the fitness function. The devised method obtains minimum mean squared error (MSE), root mean square error (RMSE), mean absolute error (MAE) of 0.020, 0.142, and 0.029 for the All India Rainfall Index (AIRI) dataset.","PeriodicalId":50231,"journal":{"name":"Journal of Combinatorial Optimization","volume":"127 1","pages":""},"PeriodicalIF":1.0,"publicationDate":"2024-04-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140807367","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

Constrained heterogeneous two-facility location games with sum-variant 具有和变数的受约束异质双设施位置博弈

IF 1 4区数学

Journal of Combinatorial Optimization Pub Date : 2024-04-27 DOI: 10.1007/s10878-024-01163-5

Qi Zhao, Wenjing Liu, Qingqin Nong, Qizhi Fang

{"title":"Constrained heterogeneous two-facility location games with sum-variant","authors":"Qi Zhao, Wenjing Liu, Qingqin Nong, Qizhi Fang","doi":"10.1007/s10878-024-01163-5","DOIUrl":"https://doi.org/10.1007/s10878-024-01163-5","url":null,"abstract":"We study deterministic mechanism design for constrained heterogeneous two-facility location games. The constraint here means that the feasible locations of facilities are specified and the number of facilities that can be built at each feasible location is limited. Given that a set of agents can strategically report their locations on the real line, the authority wants to design strategyproof mechanisms (i.e., mechanisms that can incentivize agents to report truthful private information) to construct two heterogeneous facilities under constraint, while optimizing the corresponding social objectives. Assuming that each agent’s individual objective depends on the sum of her distance to facilities, we consider locating desirable and obnoxious facilities respectively. For the former, we give a deterministic group strategyproof mechanism, which guarantees 3-approximation under the objectives of minimizing the sum cost and the maximum cost. We show that no deterministic strategyproof mechanism can have an approximation ratio of less than 2 under the sum/maximum cost objective. For the latter, we give a deterministic group strategyproof mechanism with 2-approximation under the objectives of maximizing the sum utility and the minimum utility. We show that no deterministic strategyproof mechanism can have an approximation ratio of less than 3/2 under the sum utility objective and 2 under the minimum utility objective, respectively.","PeriodicalId":50231,"journal":{"name":"Journal of Combinatorial Optimization","volume":"20 1","pages":""},"PeriodicalIF":1.0,"publicationDate":"2024-04-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140807380","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

Approximation algorithm for the minimum partial connected Roman dominating set problem 最小部分相连罗马支配集问题的近似计算算法

IF 1 4区数学

Journal of Combinatorial Optimization Pub Date : 2024-04-26 DOI: 10.1007/s10878-024-01124-y

Yaoyao Zhang, Zhao Zhang, Ding-Zhu Du

引用次数: 0

Spread of influence with incentives in edge-weighted graphs with emphasis on some families of graphs 边缘加权图中有激励机制的影响力扩散，重点是一些图族

IF 1 4区数学

Journal of Combinatorial Optimization Pub Date : 2024-04-25 DOI: 10.1007/s10878-024-01164-4

Siavash Askari, Manouchehr Zaker

{"title":"Spread of influence with incentives in edge-weighted graphs with emphasis on some families of graphs","authors":"Siavash Askari, Manouchehr Zaker","doi":"10.1007/s10878-024-01164-4","DOIUrl":"https://doi.org/10.1007/s10878-024-01164-4","url":null,"abstract":"Let (G=(V, E)) be a graph that represents an underlying network. Let (tau ) (resp. ({textbf{p}})) be an assignment of non-negative integers as thresholds (resp. incentives) to the vertices of G. The discrete time activation process with incentives corresponding to ((G, tau , {textbf{p}})) is the following. First, all vertices u with ({textbf{p}}(u)ge tau (u)) are activated. Then at each time t, every vertex u gets activated if the number of previously activated neighbors of u plus ({textbf{p}}(u)) is at least (tau (v)). The optimal target vector problem (OTV) is to find the minimum total incentives ({sum }_{vin V} {textbf{p}}(v)) that activates the whole network. We extend this model of activation with incentives, for graphs with weighted edges such that the spread of activation in the network depends on the weight of influence between any two participants. The new version is more realistic for the real world networks. We first prove that the new problem OTVW, is (texttt {NP})-complete even for the complete graphs. Two lower bounds for the minimum total incentives are presented. Next, we prove that OTVW has polynomial time solutions for (weighted) path and cycle graphs. Finally, we extend the discussed model and OTV, for bi-directed graphs with weighted edges and prove that to obtain the optimal target vector in weighted bi-directed paths and cycles has polynomial time solutions.\u0000","PeriodicalId":50231,"journal":{"name":"Journal of Combinatorial Optimization","volume":"51 1","pages":""},"PeriodicalIF":1.0,"publicationDate":"2024-04-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140642742","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

Approximation algorithms for maximum weighted target cover problem with distance limitations 有距离限制的最大加权目标覆盖问题的近似算法

IF 1 4区数学

Journal of Combinatorial Optimization Pub Date : 2024-04-22 DOI: 10.1007/s10878-024-01166-2

Jianhong Jin, Yingli Ran, Zhao Zhang

{"title":"Approximation algorithms for maximum weighted target cover problem with distance limitations","authors":"Jianhong Jin, Yingli Ran, Zhao Zhang","doi":"10.1007/s10878-024-01166-2","DOIUrl":"https://doi.org/10.1007/s10878-024-01166-2","url":null,"abstract":"In this paper, we study approximation algorithms for the problem of maximum weighted target cover with distance limitations (MaxWTCDL). Given n targets (T=left{ t_{1},t_{2},ldots ,t_{n}right} ) on the plane and m mobile sensors (S=left{ s_{1},s_{2},ldots ,s_{m}right} ) randomly deployed on the plane, each target (t_i) has a weight (w_{i}) and the sensing radius of the mobile sensors is (r_{s}), suppose there is a movement distance constraint b for each sensor and a total movement distance constraint B, where (B>b), the goal of MaxWTCDL is to move the mobile sensors within the distance constraints b and B to maximize the weight of covered targets. We present two polynomial time approximation algorithms. One is greedy-based, achieving approximation ratio (frac{1}{2v}) in time (O(mn^2)), where . The other is LP-based, achieving approximation ratio (frac{1}{v}(1-e^{-1})) in time (T_{LP}), where (T_{LP}) is the time needed to solve the linear program.","PeriodicalId":50231,"journal":{"name":"Journal of Combinatorial Optimization","volume":"39 1","pages":""},"PeriodicalIF":1.0,"publicationDate":"2024-04-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140637638","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

Cooperation models in automotive supply chain under low-carbon emission reduction policies 低碳减排政策下汽车供应链的合作模式

IF 1 4区数学

Journal of Combinatorial Optimization Pub Date : 2024-04-21 DOI: 10.1007/s10878-024-01160-8

Yukun Cheng, Zhanghao Yao, Tingting Meng

{"title":"Cooperation models in automotive supply chain under low-carbon emission reduction policies","authors":"Yukun Cheng, Zhanghao Yao, Tingting Meng","doi":"10.1007/s10878-024-01160-8","DOIUrl":"https://doi.org/10.1007/s10878-024-01160-8","url":null,"abstract":"For the issue of carbon emission mitigation within the automotive supply chain, the cooperation between the vehicle manufacturers and the retailers has been proved to be an efficient measure to enhance emission reduction endeavors. This paper aims to evaluate the effectiveness of the cooperations between a vehicle manufacturer and multiple retailers based on the differential game method. By utilizing the Hamilton–Jacobi–Bellman equation, the equilibrium strategies of the participants under two different cooperation models, i.e., the decentralized model and the Stackelberg leader–follower cooperation model, are analyzed. To be specific, in the decentralized model, each participant independently decides its strategies, whereas the manufacturer cooperates with retailers by offering subsidies in the Stackelberg leader–follower model. Unlike previous studies that solely focused on participants’ decision-making in carbon emission reduction efforts, this paper also examines the retail pricing decisions of the retailers. Additionally, carbon trading is introduced to enhance the realism of our model. Through the theoretical analysis and the numerical experiments on the carbon emission reduction efforts of manufacturers and retailers, as well as the low-carbon reputation of vehicles and the overall system profit under both models, we conclude that the cooperative Stackelberg model outperforms the decentralized model in providing benefits to both parties. Furthermore, such a cooperative approach can foster the long-term development of the automotive supply chain, ultimately contributing to a more sustainable low-carbon future.","PeriodicalId":50231,"journal":{"name":"Journal of Combinatorial Optimization","volume":"122 1","pages":""},"PeriodicalIF":1.0,"publicationDate":"2024-04-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140622736","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