• 전기학회논문지P
• /
• 제64권4호
• /
• pp.315-320
• /
• 2015

Proposal algorithm in this paper introduced cells, units of router group, for distributed processing of previous genetic algorithm. This paper presented ways to reduce search delay time of overall network through cell-based genetic algorithm. As a result of performance analysis comparing with existing genetic algorithm through experiments, the proposal algorithm was verified superior in terms of costs and delay time. Furthermore, time for routing an alternative path was reduced in proposal algorithm, in case that a network was damaged in existing optimal path algorithm, Dijkstra algorithm, and the proposal algorithm was designed to route an alternative path faster than Dijkstra algorithm, as it has a 2nd shortest path in cells of the damaged network. The study showed that the proposal algorithm can support routing of alternative path, if Dijkstra algorithm is damaged in a network.

• 한국통신학회논문지
• /
• 제28권8A호
• /
• pp.598-606
• /
• 2003

본 논문에서는 비동기 WCDMA 시스템의 빠른 셀 탐색을 위해 제안된 극성변조(PCM. Polarization Code Modulation) 셀 탐색 기법의 성능을 분석하고자 한다. 극성변조 셀 탐색 기법은 비동기 WCDMA 시스템의 표준 셀 탐색 알고리즘의 셀 탐색 시간을 단축하고 또한 수신기의 복잡도를 줄일 수 있는 기법으로, 홀드 코드를 이용하여 생성된 새로운 그룹 코드를 정의하고 이를 WCDMA P-SCH에 극성 변조하여, 기존 WCDMA의 2단계에서 사용되던 S-SCH의 그룹 코드(RS code)를 대체한다. 따라서 WCDMA 표준에 정의된 2개의 동기 채널을 하나로 줄일 수 있기 때문에 기존 WCDMA 셀 탐색 알고리즘에 비해 기지국 신호의 이득을 얻을 수 있는 기법이다. 본 논문에서는 극성변조 셀 탐색 알고리즘의 성능을 평가하기 긴하여 수학적 모델을 정의하고, 이를 통해 셀 탐색 성공 확률과 평균 탐색 시간을 이론적으로 분석하였다. 그 결과 극성변조 셀 탐색 알고리즘은 WCDMA 표준 셀 탐색 알고리즘의 성능에 비해 수신기 복잡도 측면과 셀 탐색 시간 측면에서 장점을 가지는 것을 확인할 수 있었다.

• 소성∙가공
• /
• 제6권5호
• /
• pp.416-424
• /
• 1997

In the present study, a contact search and check algorithm for general tool surface described by triangular FE patch is proposed. To improve numerical stability, SEAM element using the linear Coons interpolation has been used. To check the proposed algorithm, both clover cup and L-shape cup deep drawing processes are calculated. The computed results shows that the proposed contact algorithm can be successfully applied for sheet metal forming processes with general shaped tools.

• 한국정보디스플레이학회:학술대회논문집
• /
• 한국정보디스플레이학회 2008년도 International Meeting on Information Display
• /
• pp.749-752
• /
• 2008

Various Motion Estimation (ME) algorithms have been proposed since ME requires large computational complexity. The proposed algorithm employs Enhanced Cross Search Pattern (ECSP) using motion vector of neighbor-blocks to search the motion vector. The experimental results show that proposed algorithm reduces the search point up to 35% compared to conventional methods.

• 한국소음진동공학회논문집
• /
• 제12권6호
• /
• pp.478-487
• /
• 2002

This paper presents a hybrid method to compute the solutions of an optimization Problem. The present hybrid algorithm is the synthesis of an artificial life algorithm and the random tabu search method. The artificial life algorithm has the most important feature called emergence. The emergence is the result of dynamic interaction among the individuals consisting of the system and is not found in an individual. The conventional artificial life algorithm for optimization is a stochastic searching algorithm using the feature of artificial life. Emergent colonies appear at the optimum locations in an artificial ecology. And the locations are the optimum solutions. We combined the feature of random-tabu search method with the conventional algorithm. The feature of random-tabu search method is to divide any given region into sub-regions. The enhanced artificial life algorithm (EALA) not only converge faster than the conventional artificial life algorithm, but also gives a more accurate solution. In addition, this algorithm can find all global optimum solutions. The enhanced artificial life algorithm is applied to the optimum design of high-speed, short journal bearings and its usefulness is verified through an optimization problem.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• 제9권1호
• /
• pp.242-259
• /
• 2015

Three-dimensional video coding is one of the main challenges restricting the widespread applications of 3D video and free viewpoint video. In this paper, a novel fractal coding algorithm with motion-vector-field-based motion estimation for depth map sequence is proposed. We firstly add pre-search restriction to rule the improper domain blocks out of the matching search process so that the number of blocks involved in the search process can be restricted to a smaller size. Some improvements for motion estimation including initial search point prediction, threshold transition condition and early termination condition are made based on the feature of fractal coding. The motion-vector-field-based adaptive hexagon search algorithm on the basis of center-biased distribution characteristics of depth motion vector is proposed to accelerate the search. Experimental results show that the proposed algorithm can reach optimum levels of quality and save the coding time. The PSNR of synthesized view is increased by 0.56 dB with 36.97% bit rate decrease on average compared with H.264 Full Search. And the depth encoding time is saved by up to 66.47%. Moreover, the proposed fractal depth map sequence codec outperforms the recent alternative codecs by improving the H.264/AVC, especially in much bitrate saving and encoding time reduction.

• 산업공학
• /
• 제22권1호
• /
• pp.10-16
• /
• 2009

In this paper, we propose an efficient search algorithm for finding an optimal schedule to minimize makespan, while avoiding deadlock situation in Flexible Manufacturing Systems (FMS) with finite capacity, in which each job needs to be processed in several job stages for completion. The proposed algorithm uses a modeling and control method based on Petri-net. Especially, we improve the efficiency of the search algorithm by using a priority rule and an efficient bounding function during the search procedure. The performance of the proposed algorithm is evaluated through a numerical experiment, showing that it holds considerable promise for providing an optimal solution efficiently comparing to past work.

• 전기학회논문지
• /
• 제59권5호
• /
• pp.866-870
• /
• 2010

This paper presents a application of Harmony Search (HS) algorithm for optimal placement of distributed generations(DGs) in distribution systems. In optimization procedure, the HS algorithm denotes the searching ability for the global optimal solution with simple coding of the iteration procedure, and shows the fast convergence characteristics for getting solutions. The HS algorithm is tested on 9 buses and 69 buses distribution systems, and the results prove its effectiveness to determine appropriate placement points of DGs and reducing amount of active power without the occurrence of any mis-determination in selection of its capacity.

• 한국정보과학회논문지:시스템및이론
• /
• 제33권7호
• /
• pp.448-453
• /
• 2006

본 논문은 평면 그래프를 위한 병렬 depth-first search (DFS) 알고리즘 [SIAM J. Comput., 19 (1990) 678-704]을 비 평면일 (non-planar) 수 있는 grid 그래프의 한 종류인 solid grid 그래프에 대해서도 수행 가능하도록 확장된 알고리즘을 제안한다. 제안 알고리즘은 Priority PRAM 모델에서 $O(n/sqrt{log\;n})$개의 프로세서로 수행했을 때 O(log n)의 병렬 시간이 소요된다. 우리의 지식으로, 이는 비 평면 그래프를 위한 첫 번째 결정적 NC (deterministic NC) 알고리즘이다.

• 전기학회논문지
• /
• 제58권9호
• /
• pp.1667-1673
• /
• 2009

This paper presents a application of new algorithm for feeder reconfiguration problem in distribution systems. Harmony Search (HS) algorithm, which is motivated from the musical performance, is used to reconfigure distribution systems so that active power losses are globally minimized with turning on/off the sectionalizing and the tie-line switches. In optimization processing, the HS algorithm has searching ability for the global optimal solution, simple coding of the iteration procedure, and fast convergence to get the solution. The HS algorithm is tested on 15 buses and 69 buses distribution systems, and the results prove its effectiveness to determine appropriate switching options without the occurrence of any misdetermination in switching and get the minimum power loss.