• Journal of Korea Multimedia Society
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• v.3 no.3
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• pp.298-308
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• 2000

We present an efficient algorithm for finding the sequence of extreme vortices of a moving regular convex polyhedron of with respect to a fixed plane H.. The algorithm utilizes the spherical Voronoi diagram that results from the outward unit normal vectors nF$_{i}$ 's of faces of P. It is well-known that the Voronoi diagram of n sites in the plane can be computed in 0(nlogn) time, and this bound is optimal. However. exploiting the convexity of P, we are able to construct the spherical Voronoi diagram of nF$_{i}$ ,'s in O(n) time. Using the spherical Voronoi diagram, we show that an extreme vertex problem can be transformed to a spherical point location problem. The extreme vertex problem can be solved in O(logn) time after O(n) time and space preprocessing. Moreover, the sequence of extreme vertices of a moving regular convex polyhedron with respect to H can be found in (equation omitted) time, where m$^{j}$ $_{k}$ (1$\leq$j$\leq$s) is the number of edges of a spherical Voronoi region sreg(equation omitted) such that (equation omitted) gives one or more extreme vertices.

• Journal of the Korean Institute of Intelligent Systems
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• v.15 no.6
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• pp.661-667
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• 2005

In this paper, we propose a new hybrid genetic algorithm for sequential ordering problem (SOP). In the proposed genetic algorithm, the Voronoi quantized crossover (VQX) is used as a crossover operator and the path-preserving 3-Opt is used as a local search heuristic. VQX is a crossotver operator that uses the epistasis information of given problem instance. Since it is a crossover proposed originally for the traveling salesman problem (TSP), its application to SOP requires considerable modification. In this study, we appropriately modify VQX for SOP, and develop three algorithms, required in the modified VQX, named Feasible solution Generation Algorithm, Precedence Cycle Decomposition Algorithm, and Genic Distance Assignment Method. The results of the tests on SOP instances obtained from TSPLIB and ZIB-MP-Testdata show that the proposed genetic algorithm outperforms other genetic algorithms in stability and solution quality.

• Spatial Information Research
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• v.15 no.3
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• pp.203-218
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• 2007

The purpose of this article is to set up the scientific and reasonable norm of location and service area determination instead of the pro-administrative lacking availability, so as to propose more practical and reasonable standard of space unit for the location of facilities. This article has accepted the method of Voronoi Diagram as a new scientific and reasonable criteria. The article chooses and realizes a model that can propose a new service area, transform and apply to improve its reality, and assesses which has more reality and compatibility by comparing the models. The result from this procedure can be adapted in objectification of the service area determination and formation of the standard space unit.

• 한국HCI학회:학술대회논문집
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• 2006.02a
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• pp.1361-1366
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• 2006

본 논문에서는 제약되지 않은 카메라에서 얻어진 회전과 크기 변화를 가진 영상들을 특징 기반의 보로노이 거리 매칭 방법을 이용하여 고속으로 합성 하는 기법에 관해 기술한다. 기존의 특징점 기반 매칭 기법들이 사람의 개입에 의해 영상을 정합하거나, 크기나 회전 변화를 고려하지 않은 형태의 영상들을 처리하는 것과 달리 회전이나 크기변화요소가 포함된 입력영상들을 사람의 개입이 없이 자동으로 정확한 중첩영역을 빠르게 검색하는 방법을 제안한다. 제안된 방법은 우선 영상내의 특징 점들의 위상 정보와 특징 점들 사이의 거리 정보를 가지는 보로노이 거리 정합법을 통해 대응점을 구하고, 찾아진 대응 쌍들을 이용하여 2차원 투영의 초기 변환행렬을 구한다. 다음으로 비선형 이승오차 최적화 알고리즘을 이용하여 최적의 변환 행렬을 구한 후, 마지막으로 구해진 변환 행렬을 이용하여 영상을 합성한다. 실험결과를 통해 본 논문에서 제안한 방법의 효율성을 보인다.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.41 no.6
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• pp.247-252
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• 2004

This paper proposes a matching algorithm using Voronoi diagram for rotation and translation invariant fingerprint identification. The proposed algorithm extracts geometrical structures that are derived from Voronoi diagram of a fingerprint image. Then two features, distances and angles are extracted from the geometrical structures and saved as indexing form for fingerprint matching. This matching algerian has a lower error rate than indexing based methods of old times.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.38A no.3
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• pp.224-239
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• 2013

An exact performance analysis of an ML detector for a 2-dimensional rotation-transform aided QPSK system operating over an impulsive noise environment is presented using Rieman integrals of a two-dimensional Gaussian Q-function over Voronoi cells. A set of interesting features of the Voronoi cells is also characterised systematically. An optimum rotation angle yielding the minimum BER is also studied. The differences between the proposed exact method and the previous approximate analysis method are investigated in terms of the corresponding BERs and the derived optimum angles.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1996.11a
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• pp.833-840
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• 1996

중립면은 셸 (솔리드 모델) 유한 요소 생성, 로보트 이동 경로 계산, 특징 형상 판별 등에서 사용될 수 있다. 그러나 기존 중립면 계산 알고리즘들은 연립 방정식을 수렴성이 보장되지 않는 수치 해법으로 풀어야 했기 때문에 발전이 미비했다. 본 논문은 복셀-이등분 면의 교자성을 이용한 중립면 계산 알고리즘을 제시한다. 교차성은 보로노이 영역을 사용, 단순한 기하학적 요소간의 거리 비교로 판별한다. 이런 기하학적인 접근 방법은 기본적으로 수렴성 문제가 배제된다.

• Journal of Korea Multimedia Society
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• v.6 no.7
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• pp.1178-1188
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• 2003

In this paper, we describe image mosaicing techniques for constructing a large high-resolution image with images taken by a video camera in hand. we propose the method which is automatically retrieving the exact matching area using color information and shape information. The proposed method extracts first candidate areas which have similar form using a Voronoi Distance Matching Method which is rapidly estimating the correspondent points between adjacent images, and calculating initial transformations of them and finds the final matching area using color information. It is a method that creates Voronoi Surface which set the distance value among feature points and other points on the basis of each feature point of a image, and extracts the correspondent points which minimize Voronoi Distance in matching area between an input image and a basic image using the binary search method. Using the Levenberg-Marquadt method we turn an initial transformation matrix to an optimal transformation matrix, and using this matrix combine a basic image with a input image.

• Journal of Aerospace System Engineering
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• v.18 no.3
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• pp.1-7
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• 2024

The utilization of Unmanned Aerial Vehicles (UAVs) is expanding in various industries such as logistics, manufacturing, and transportation. However, to operate a large number of UAVs, it is imperative to first plan a secure and efficient self-configuring communication network for UAVs. In this study, we proposed a method for planning a secure and efficient UAV self-configuring communication network using Voronoi diagrams in the following three steps: 1) generating Voronoi diagrams using obstacles, 2) selecting obstacles to consider for path generation, and 3) planning the optimal path and outputting the path. The real-time feasibility of using the proposed method for planning optimal communication paths for a realistic number of UAVs was experimentally validated.

• Journal of the Korean Institute of Intelligent Systems
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• v.9 no.5
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• pp.490-495
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• 1999

In this paper. a learning method VoD-EBP for neural networks is proposed, which learn patterns by error back propagation. Based on Voronoi diagram, the method initializes the weights of the neural networks systematically, wh~ch results in faster learning speed and alleviated local optimum problem. The method also shows better the reliability of the design of neural network because proper number of hidden nodes are determined from the analysis of Voronoi diagram. For testing the performance, this paper shows the results of solving the XOR problem and the parity problem. The results were showed faster learning speed than ordinary error back propagation algorithm. In solving the problem, local optimum problems have not been observed.