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An exact algorithm for solving the ring star problem

Safia Kedad-Sidhoum, Viet Hung Nguyen
2010 Optimization  
This paper deals with the ring star problem that consists in designing a ring that pass through a central depot, and then assigning each non visited customer to a node of the ring.  ...  A large set of instances are tested and show the effectiveness of the method that outperforms the results previously obtained on the problem.  ...  The purpose of this paper is to propose a branch and cut exact algorithm for the ring star problem.  ... 
doi:10.1080/02331930903500332 fatcat:lfvggo5ejvdj3pu43bsppcpouq

An efficient evolutionary algorithm for the ring star problem

Herminia I. Calvete, Carmen Galé, José A. Iranzo
2013 European Journal of Operational Research  
This paper addresses the ring star problem (RSP).  ...  Moreover, for one of the problems a new best solution is found.  ...  Acknowledgments The authors gratefully acknowledge the anonymous referees for their valuable suggestions to improve the presentation of the paper.  ... 
doi:10.1016/j.ejor.2013.05.013 fatcat:fhw543s75neorpwxq4dekjucyq

Particle Swarm Optimization Algorithm with Multiple Phases for Solving Continuous Optimization Problems

Jing Li, Yifei Sun, Sicheng Hou, Lianbo Ma
2021 Discrete Dynamics in Nature and Society  
An algorithm with different parameter settings often performs differently on the same problem. The parameter settings are difficult to determine before the optimization process.  ...  Based on the concept of building block thesis, a PSO algorithm with multiple phases was proposed to analyze the relation between search strategies and the solved problems.  ...  the PSO algorithm for specific problems.  ... 
doi:10.1155/2021/8378579 fatcat:46ozwthhgzf2daj3ycap2a5qhm

Maximizing the Number of Connections in Multifiber WDM Chain, Ring and Star Networks [chapter]

Katerina Potika
2005 Lecture Notes in Computer Science  
We propose polynomial time algorithms, that are either optimal or have a guaranteed worst case performance in basic topologies, such as chain, ring and star networks.  ...  We study a wavelength assignment maximization problem in multifiber WDM networks.  ...  The iterative algorithm for Max-PMC in stars is a 1.58approximation algorithm. Conclusions and Open Problems In this paper we present algorithms for Max-PMC in chains, rings and stars.  ... 
doi:10.1007/11422778_139 fatcat:w4uo2a7yz5a2tgzy77wiwkvtm4

An equi-model matheuristic for the multi-depot ring star problem

Alessandro Hill, Stefan Voß
2016 Networks  
In the multi-depot ring star problem (MDRSP) a set of customers has to be connected to a set of given depots by ring stars.  ...  For both purposes we develop an exact branch & cut algorithm for the MDRSP that efficiently solves the local optimization problems to optimality, if they are chosen reasonably in terms of size and complexity  ...  Acknowledgments We are indebted to Roberto Baldacci for providing the test instances, detailed results and the correspondence.  ... 
doi:10.1002/net.21674 fatcat:fzpvyxtombfolgzrz7npncvtvu

Intelligent Image Segment for Material Composition Detection

Xiaodan Liang, Na Lin, Hanning Chen, Wenxin Liu, L. Zhao, A. Xavior, J. Cai, L. You
2017 MATEC Web of Conferences  
To overcome this problem, this paper proposed an artificial bee colony algorithm with a two-level topology.  ...  In the process of material composition detection, the image analysis is an inevitable problem. Multilevel thresholding based OTSU method is one of the most popular image segmentation techniques.  ...  The two variants of ABC algorithm with the ring colony and the ring swarm and ABC algorithm with the star colony and the ring swarm have nearly the same results.  ... 
doi:10.1051/matecconf/201710004026 fatcat:qf7lb3nmszerlhem75gxy3p6tm

A branch-and-cut-and-price approach for the capacitated m-ring–star problem

Edna A. Hoshino, Cid C. de Souza
2012 Discrete Applied Mathematics  
The capacitated m-ring-star problem is a variant of the classical one-depot capacitated vehicle routing problem in which a customer is either on a route or is connected to another customer or to some Steiner  ...  We develop a new exact algorithm for this problem using a branch-and-cut-and-price approach and compare its performance with that of a branch-and-cut algorithm proposed earlier in the literature.  ...  Acknowledgments We would like to thank Professor Baldacci and Salari for providing the source code of their heuristics and for giving us useful information about the approaches they used.  ... 
doi:10.1016/j.dam.2011.11.029 fatcat:p377r5jjpzddzhng4sl46plpte

Fiber Cost Reduction and Wavelength Minimization in Multifiber WDM Networks [chapter]

Christos Nomikos, Aris Pagourtzis, Katerina Potika, Stathis Zachos
2004 Lecture Notes in Computer Science  
We present exact or constant-ratio approximation algorithms for all the above variations in chain, ring, star and spider networks. R is a set of pair of nodes.  ...  Moreover, for rings we also study the problern in the case of pre-determined routing.  ...  for MINWAv-PMC in rings as well as for the directed version of both problems in rings.  ... 
doi:10.1007/978-3-540-24693-0_13 fatcat:kphq6gnddzg7zgjpry2vavreva

Approximating Call-Scheduling Makespan in All-Optical Networks [chapter]

Luca Becchetti, Miriam Di Ianni, Alberto Marchetti-Spaccamela
2000 Lecture Notes in Computer Science  
As a side result, we present a constant approximation algorithm for star networks.  ...  Independently from the relationship with path coloring we propose different approximation algorithms for call scheduling in trees and in trees of rings.  ...  In particular, they propose constant approximation algorithms for stars and O(log m)-approximation algorithms for trees (where m is the number of nodes).  ... 
doi:10.1007/3-540-40064-8_3 fatcat:pipp733zozb25fypjixnx4daxe

Low-Complexity Near-ML Detection Algorithms for NR-STAR-MQAM Spatial Modulation

R. Pillay, H. Xu, N. Pillay
2018 SAIEE Africa Research Journal  
In this study, the authors propose two low-complexity near-maximum-likelihood (ML) detection algorithms for spatial modulation (SM) systems, employing the new multiple-ring star-M-ary quadrature amplitude  ...  As a result, the computational complexity is independent of both the constellation size and the number of rings presented in NR-STAR-MQAM.  ...  Note, the optimum radii for NR-STAR-MQAM-SM is efficiently calculated using the optimum ring radii algorithm in [22] .  ... 
doi:10.23919/saiee.2018.8532195 fatcat:nxfg2nttxjfn3kx6uoknu6xzta

Exploration of Constantly Connected Dynamic Graphs Based on Cactuses [chapter]

David Ilcinkas, Ralf Klasing, Ahmed Mouhamadou Wade
2014 Lecture Notes in Computer Science  
This problem has already been studied in the case where the agent knows the dynamics of the graph and the underlying graph is a ring of n vertices [5] .  ...  We propose an algorithm that allows the agent to explore these dynamic graphs in at most 2 O( √ log n) n time units. We show that the lower bound of the algorithm is 2 Ω( √ log n) n time units.  ...  cost (1), we use the following algorithm for exploring a dynamic ring.  ... 
doi:10.1007/978-3-319-09620-9_20 fatcat:umjiagsennbq7ewlveukoqwfse

On the Integration of a TSP Heuristic into an EA for the Bi-objective Ring Star Problem [chapter]

Arnaud Liefooghe, Laetitia Jourdan, Nicolas Jozefowiez, El-Ghazali Talbi
2008 Lecture Notes in Computer Science  
This paper discusses a new hybrid solution method for a bi-objective routing problem, namely the bi-objective ring star problem.  ...  The bi-objective ring star problem is a generalization of the ring star problem in which the assignment cost has been dissociated from the cost of visiting a subset of nodes.  ...  . , f n (x) The Bi-objective Ring Star Problem The Bi-objective Ring Star Problem (B-RSP) can be described as follows.  ... 
doi:10.1007/978-3-540-88439-2_9 fatcat:6mpgef2xzjc75mjnnjfh4b2mri

Approximating call-scheduling makespan in all-optical networks

Luca Becchetti, Miriam Di Ianni, Alberto Marchetti-Spaccamela
2004 Journal of Discrete Algorithms  
We also propose different approximation algorithms for stars, trees and in trees of rings.  ...  We study the relationship between this problem and minimum path coloring and we show how to exploit known results on path coloring to derive approximation scheduling algorithms for meshes, trees and nearly-Eulerian  ...  Schedule calls that traverse v 0 using the MIN-CS algorithm for directed stars.  ... 
doi:10.1016/j.jda.2004.04.008 fatcat:6eopeel6l5fhlb36bd2w2i3p3u

Experimental Study on Boundary Constraints Handling in Particle Swarm Optimization

Shi Cheng, Yuhui Shi, Quande Qin
2011 International Journal of Swarm Intelligence Research  
Premature convergence happens in Particle Swarm Optimization (PSO) for solving both multimodal problems and unimodal problems.  ...  problems.  ...  As indicated by the "no free lunch theory", there is no algorithm that is better than other one on average for all problems [28] . Different variant of PSO fits for different kinds of problems.  ... 
doi:10.4018/jsir.2011070104 fatcat:656t3ukiynazdneyqtnkbopyiq

TornadoAggregate: Accurate and Scalable Federated Learning via the Ring-Based Architecture [article]

Jin-woo Lee, Jaehoon Oh, Sungsu Lim, Se-Young Yun, Jae-Gil Lee
2021 arXiv   pre-print
Nevertheless, such ring-based algorithms can inherently suffer from the high-variance problem.  ...  In particular, to improve the accuracy, we reformulate the loss minimization into a variance reduction problem and establish three principles to reduce variance: Ring-Aware Grouping, Small Ring, and Ring  ...  for the rest of algorithms.  ... 
arXiv:2012.03214v2 fatcat:3mj7xcrjtvhlzm2e5g3i4m2egq
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