• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.16 no.1
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• pp.58-66
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• 2002

Electric power facilities must have effective grounding to provide means to carry electric current into the earth under fault conditions and to prevent damage of equipment, ignition, and electrocution of personnel. This paper resent an algorithm called the Pattern Search method for the optimal parameters selection of the grounding system Simulation results using these parameters obtained from the PS method verify that the grounding systems are adequately designed.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2003.11a
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• pp.43-48
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• 2003

축구 전용 경기장에서 캐노피에 설치되는 등기구의 위치를 Pattern Search법을 이용하여 컴퓨터 시뮬레이션하였다. 조명 등기구 배치간격을 변화시키는 시뮬레이션을 통해 국·내외(FIFA, 유럽방송연맹, KS) 기준에 명시된 수평면 조도, 수직면 조도, 균제도, 눈부심 정도에 적합한 최적의 값을 찾았었다. 향후 국내 축구 전용 경기장 조명기구의 설계 및 시공, 유지관리 보수시 많은 참고가 되었으면 한다.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.18 no.4
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• pp.181-187
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• 2004

With the proliferation of nonlinear loads, high neutral harmonic currents in three-phase four-wire distribution system have been observed. It has been known that the ground impedance has an effect on the neutral currents of a system which operates with harmonics present. On-site measurements of harmonic currents and voltages according to the fall-of-potential method under case study system were made and the ground impedance modeling using the pattern search method for the harmonic analysis was developed The ground impedance model obtained by the proposed method was compared with the frequency characteristics by field tests and has shown appropriate results, and would be applicable to evaluate the harmonic and transient response characteristics of the ground system.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2001.11a
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• pp.173-180
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• 2001

Electric power facilities must have effective grounding to provide means to carry electric current into the earth under fault conditions and to prevent damage of equipment, Ignition, and electrocution of presonnel. nuts paper present an algorithm called the Pattern Search method for the optimal parameters selection of the grounding system. Computer simulation results used the CDEGS grounding analysis program verifying the effects of the grounding system design parameters obtained from this method show that the grounding systems are adequately designed.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.24 no.1
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• pp.63-68
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• 2015

Pattern layout design is very important to the automation of apparel industry. Until now, the genetic algorithm and Tabu search method have been applied to layout design automation. With the genetic algorithm and Tabu search method, the obtained values are not always consistent depending on the initial conditions, number of iterations, and scheduling. In addition, the selection of various parameters for these methods is not easy. This paper presents a hybrid search method that uses a neural network and simulated annealing to solve these problems. The layout of pattern elements was optimized to verify the potential application of the suggested method to apparel pattern layout design.

• Proceedings of the Korea Water Resources Association Conference
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• 2002.05b
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• pp.1316-1321
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• 2002

일반적으로 강우-유출모형은 lumped model과 distributed model로 크게 구분될 수 있으며, 우리나라에서는 이중 비교적 부족한 자료를 이용하여도 개략적 모의가 가능한 전자를 널리 사용하고 있다. 본 연구에서는 이러한 모형들의 매개변수를 보정하는 방법에 관해 연구하였다. 일반적으로 모형의 보정 방법에는 크게 시행오차에 의한 수동보정(manual calibration) 방법과 최적화 기법에 의한 자동보정(automatic calibration) 방법으로 나눌 수 있다. 수동보정 방법은 모형 수행결과를 수문곡선의 시각적 비교에 의해 관측치와 비교하여 모형 운영자의 주관적인 판단하에 조정하는 기법이며, 자동보정 방법은 최적화 기법을 이용8하여 특정한 산정기준(estimation criteria)을 최대 또는 최소화시켜 모형의 매개변수를 결정하는 방법이다. 이러한 최적화기법은 일반적으로 직접탐색법과 경사법으로 구분할 수 있다. 경사법은 수렴속도가 빠르지만 편미분에 의해 방향을 찾아가는 방법으로 편도함수가 필요하므로 수문모형에는 적용하기가 힘들므로 적합하지 않다. 그러나, 보다 많은 컴퓨터 수행시간을 필요로 하는 직접탐색법의 경우 수렴속도는 느리지만, 편도함수를 필요치 않으므로 수문모형의 최적화 기법으로 적합하다고 할 수 있다. 직접탐색법에는 simplex-search 법, 패턴인식(pattern-search)법, rotating-direction 법, brent 법 등이 있으며, 본 연구에서는 직접탐색법의 일종인 패턴인식(pattern -search)법을 이용하여 매개변수 최적화 과정을 모의하였다. 이러한 매개변수 보정모형을 구성한 후 이를 가장 보편적으로 사용되고 있는 유출모형인 각종 단위도법들을 결합하는 모형을 구성하였다. 또한 구성된 모형을 시범유역에 적용하여 나온 결과를 HEC-1에서 적용되고 있는 단일변량 증감법과 같은 최적화 기법을 이용한 결과와 비교·분석을 실시하였다. 본 모형을 활용하여 강우-유출 모형의 매개변수를 지속적으로 산정하고 일반화할 경우 임의의 유역의 수문기상학적 특성에 부합한 매개변수를 정량화 시킬 수 있었다.

• Journal of Korea Multimedia Society
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• v.3 no.4
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• pp.356-364
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• 2000

Block based fast motion estimation algorithm use the fixed search pattern to reduce the search point, and are based on the assumption that the error in the mean absolute error space monotonically decreases to the global minimum. Therefore, in case of many local minima in a search region we are likely to find local minima instead of the global minimum and highly rely on the initial search points. This situation is evident in the motion boundary. In this paper we define the candidate regions within the search region using the motion information of the neighbor blocks and we propose the multiple local search method (MLSM) which search for the solution throughout the candidate regions to reduce the possibilities of isolation to the local minima. In the MLSM we mark the candidate region in the search point map and we avoid to search the candidate regions already visited to reduce the calculation. In the simulation results the proposed method shows more excellent results than that of other gradient based method especially in the search of motion boundary. Especially, in PSNR the proposed method obtains similar estimate accuracy with the significant reduction of search points to that of full search.

• Proceedings of the KIEE Conference
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• 2004.11d
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• pp.106-109
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• 2004

축구 전용 경기장에서 캐노피에 설치되는 등기구의 위치를 Pattern Search법을 이용 컴퓨터 시뮬레이션하여 조명 등기구 배치간격을 변화시킴으로 국 내외 (FIFA, 유럽방송연맹, KS) 기준에 명시된 수평면 조도, 수직면 조도, 균제도, 눈부심 정도에 적합한 최적의 값을 찾아내어 향후 국내 축구 전용 경기장 조명기구의 설계 및 시공, 유지관리 보수시 많은 참고가 되었으면 한다.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.29 no.4D
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• pp.555-561
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• 2009

In lieu of section profile data, a fitting of the bored tunnel shape is more significant confirmation for maintenance of a tunnel. Before the permit on the completion of a tunnel, deformation of the completed tunnel with respect to the design model are considered. And deformation can be produced at continuously along the entire of the tunnel section. This study firstly includes an analysis of algebraic approach and test it with an observed field data. And then a number of methods, line search method, genetic algorithm, and pattern search methods, are compared with the 3D tunnel shape fitting. Algebraic methods can solve a simple circular cylinder type as like a railway tunnel. However, a more complex model (compound circular curve and non circular) as like a highway tunnel has to be solved with soft computing tools in the cause of conditional constraints. The genetic algorithm and pattern search methods are computationally more intensive, but they are more flexible at a complex condition. The line search method is fastest, but it needs a narrow bounds of the initial values.

• Journal of Korea Water Resources Association
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• v.39 no.7 s.168
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• pp.593-603
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• 2006

The basin response to storm is regarded as nonlinearity inherently. In addition, the consistent nonlinearity of hydrologic system response to rainfall has been very tough and cumbersome to be treated analytically. The thing is that such nonlinear models have been avoided because of computational difficulties in identifying the model parameters from recorded data. The parameters of nonlinear system considered as dynamic effects in the conceptual model are optimized as the sum of errors between the observed and computed runoff is minimized. For obtaining the optimal parameters of functions, the historical data for the Bocheong watershed in the Geum river basin were tested by applying the numerical methods, such as quasi-linearization technique, Runge-Kutta procedure, and pattern-search method. The estimated runoff carried through from the storage function with dynamic effects was compared with the one of 1st-order differential equation model expressing just nonlinearity, and also done with Nash model. It was found that the 2nd-order model yields a better prediction of the hydrograph from each storm than the 1st-order model. However, the 2nd-order model was shown to be equivalent to Nash model when it comes to results. As a result, the parameters of nonlinear 2nd-order differential equation model performed from the present study provided not only a considerable physical meaning but also a applicability to Korean watersheds.