• 제목/요약/키워드: Coloring problem

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On the k-coloring Problem

  • Park, Tae-Hoon;Lee, Chae Y.
    • 한국경영과학회지
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    • 제19권3호
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    • pp.219-233
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    • 1994
  • A fixed k-coloring problem is introduced and dealt with by efficient heuristic algorithms. It is shown that the problem can be transformed into the graph partitioning problem. Initial coloring and improving methods are proposed for problems with and with and without the size restriction. Algorithm Move, LEE and OEE are developed by modifying the Kernighan-Lin's two way uniform partitioning procedure. The use of global information in the selection of the node and the color set made the proposed algorithms superior to the existing method. The computational result also shows that the superiority does not sacrifice the time demand of the proposed algorithms.

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Voxel Coloring을 이용한 3D 오브젝트 모델링 (Implementation of Photorealistic 3D Object Reconstruction Using Voxel Coloring)

  • ;양황규;윤태수
    • 한국정보처리학회:학술대회논문집
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    • 한국정보처리학회 2003년도 춘계학술발표논문집 (상)
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    • pp.527-530
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    • 2003
  • In this paper, we implemented the voxel coloring method to reconstruct 3D object from synthetic input Images. Then compare the result between using standard voxel coloring and using coarse-to-fine method. We compared using different voxel space site to see the difference of time processing and the result of 3D object. Photorealistic 3D object reconstruction is a challenging problem in computer graphics. Vexel coloring considered the reconstruction problem as a color reconstruction problem, instead of shape reconstruction problem. This method works by discretizing scene space into yokels, then traversed and colored those in special order. Also there is an extension of voxel coloring method far decreasing the amount of processing time called coarse-to-fine method. This. method works using low resolution instead of high resolution as input and after processing finish, apply some kind of search strategy.

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호의 색칠문제의 해법 (An Algorithm for the Edge Coloring Problem)

  • 박성수
    • 대한산업공학회지
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    • 제18권2호
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    • pp.43-49
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    • 1992
  • Edge coloring problem is to find a minimum cardinality coloring of the edges of a graph so that any pair of edges incident to a common node do not have the same colors. Edge coloring problem is NP-hard, hence it is unlikely that there exists a polynomial time algorithm. We formulate the problem as a covering of the edges by matchings and find valid inequalities for the convex hull of feasible solutions. We show that adding the valid inequalities to the linear programming relaxation is enough to determine the minimum coloring number(chromatic index). We also propose a method to use the valid inequalities as cutting planes and do the branch and bound search implicitly. An example is given to show how the method works.

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노드채색문제에 대한 기존 해법의 분석 및 분류 (Analysis and Classfication of Heuristic Algorithms for Node Coloring Problem)

  • 최택진;명영수;차동완
    • 한국경영과학회지
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    • 제18권3호
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    • pp.35-49
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    • 1993
  • The node coloring problem is a problem to color the nodes of a graph using the minimum number of colors possible so that any two adjacent nodes are colored differently. This problem, along with the edge coloring problem, has a variety of practical applications particularly in item loading, resource allocation, exam timetabling, and channel assignment. The node coloring problem is an NP-hard problem, and thus many researchers develop a number of heuristic algorithms. In this paper, we survey and classify those heuristics with the emphasis on how an algorithm orders the nodes and colors the nodes using a determined ordering.

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T-칼라링 문제를 위한 탐색공간 스무딩 Simulated Annealing 방법 (A Simulated Annealing Method with Search Space Smoothing for T-Coloring Problem)

  • 이정은;한치근
    • 대한산업공학회지
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    • 제25권2호
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    • pp.226-232
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    • 1999
  • Graph Coloring Problem(GCP) is a problem of assigning different colors to nodes which are connected by an edge. An extended form of GCP is TCP (T-coloring problem) and, in TCP, edge weights are added to GCP and it is possible to extend GCP's applications. To solve TCP, in this paper, we propose an improved Simulated Annealing(SA) method with search space smoothing. It has been observed that the improved SA method obtains better results than SA does.

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ON REFORMULATED INJECTIVE CHROMATIC INDEX OF GRAPHS

  • SALEH, ANWAR;AQEEL, A.;ALASHWALI, HANAA
    • Journal of applied mathematics & informatics
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    • 제39권1_2호
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    • pp.13-29
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    • 2021
  • For a graph G = (V, E), a vertex coloring (or, simply, a coloring) of G is a function C : V (G) → {1, 2, …, k} (using the non-negative integers {1, 2, …, k} as colors). We say that a coloring of a graph G is injective if for every vertex v ∈ V (G), all the neighbors of v are assigned with distinct colors. The injective chromatic number χi(G) of a graph G is the least k such that there is an injective k-coloring [6]. In this paper, we study a natural variation of the injective coloring problem: coloring the edges of a graph under the same constraints (alternatively, to investigate the injective chromatic number of line graphs), we define the k- injective edge coloring of a graph G as a mapping C : E(G) → {1, 2, …, k}, such that for every edge e ∈ E(G), all the neighbors edges of e are assigned with distinct colors. The injective chromatic index χ′in(G) of G is the least positive integer k such that G has k- injective edge coloring, exact values of the injective chromatic index of different families of graphs are obtained, some related results and bounds are established. Finally, we define the injective clique number ωin and state a conjecture, that, for any graph G, ωin ≤ χ′in(G) ≤ ωin + 2.

그래프 컬러링 문제를 활용한 초등학생을 위한 알고리즘 학습 (On Algorithm Learning Using Graph Coloring Problem for Elementary Students)

  • 박윤정;문교식
    • 한국콘텐츠학회논문지
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    • 제14권10호
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    • pp.840-849
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    • 2014
  • 본 연구는 알고리즘 학습을 초등학생에게 적용하여 알고리즘적 사고에 긍정적 효과가 있음을 보여준다. 알고리즘 학습에 대한 사전 경험이 없는 초등학교 6학년 35명을 대상으로 4주간 총 11회의 그래프 컬러링 문제를 활용한 알고리즘 학습을 실시하였다. 알고리즘 수업 후 학습자들의 알고리즘 흥미도와 절차적 사고능력의 변화를 검사하였다. 이와 같은 자료 분석을 통해 얻어진 연구 결과는 다음과 같다. 첫째, 알고리즘 흥미도의 하위요인인 알고리즘 학습 태도는 학습자에게 긍정적인 영향을 미치는 것으로 나타났다. 둘째, 그래프 컬러링을 활용한 알고리즘 학습은 학습자의 절차적 사고 능력을 향상시키는 것으로 나타났다. 따라서 알고리즘 학습은 초등학생의 절차적 사고 발달에 도움이 되며, 알고리즘 흥미도를 높이는 효과를 보여줌으로써 초등 교육 현장에서 알고리즘의 새로운 교육 방법을 제시하는데 의미가 있다.

A New Total Coloring Problem in Multi-hop Networks

  • Watanabe, K.;Sengoku, M.;Tamura, H.;Nakano, K.;Shinoda, S.
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2002년도 ITC-CSCC -3
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    • pp.1375-1377
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    • 2002
  • New graph coloring problems are discussed as models of a multihop network in this report. We consider a total scheduling problem, and prove that this problem is NP-hard. We propose new scheduling models of a multi-hop network for CDMA system, and show the complexity results of the scheduling problems.

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THE CLASSIFICATION OF COMPLETE GRAPHS $K_n$ ON f-COLORING

  • ZHANG XIA;LIU GUIZHEN
    • Journal of applied mathematics & informatics
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    • 제19권1_2호
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    • pp.127-133
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    • 2005
  • An f-coloring of a graph G = (V, E) is a coloring of edge set E such that each color appears at each vertex v $\in$ V at most f(v) times. The minimum number of colors needed to f-color G is called the f-chromatic index $\chi'_f(G)$ of G. Any graph G has f-chromatic index equal to ${\Delta}_f(G)\;or\;{\Delta}_f(G)+1,\;where\;{\Delta}_f(G)\;=\;max\{{\lceil}\frac{d(v)}{f(v)}{\rceil}\}$. If $\chi'_f(G)$= ${\Delta}$f(G), then G is of $C_f$ 1 ; otherwise G is of $C_f$ 2. In this paper, the classification problem of complete graphs on f-coloring is solved completely.

Graph Coloring Problem 해결을 위한 Ant Colony System의 생성함수 성능비교에 관한 연구 (Comparison of Constructive Methods In Ant Colony System For Solving Graph Coloring Problem)

  • 안상혁;이승관;정태충
    • 한국정보과학회:학술대회논문집
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    • 한국정보과학회 2001년도 가을 학술발표논문집 Vol.28 No.2 (2)
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    • pp.79-81
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    • 2001
  • 그래프 착색 문제(Graph Coloring Problem)는 인접한 노드 (V$_{i}$, V$_{j}$ )가 같은 색을 갖지 않도록 그래프 G의 노드 V에 색을 배정하는 문제로, NP-hard 문제로 잘 알려져 있다. 또한 최근까지 그래프 착색 문제의 최적 해를 구하기 위하여 다양한 접근방식들과 해법들이 제안되고 있다. 본 논문에서는 기존의 그래프 착색 문제의 해법으로 잘 알려진 Greedy algorithms, Simulated Annealing. Tabu search 등이 아닌 실세계에서 개미들이 자신의 분비물을 이용하여 경로를 찾는 Ant System을 개선하여 새롭게 제안한 Ant Colony System(ACS) 알고리즘으로 해를 구하는 ANTCOL을 소개하고, ANTCOL에서 DSATUR, Recursive Largest First(RLF) 등의 방식을 사용한 기존 생성 함수들과 RLF를 개선하여 제안한 eXtend RLF방식을 사용한 생성 함수를 비교, 평가하고자 한다.

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