• Proceedings of the Korean Society of Coastal and Ocean Engineers Conference
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• 2000.09a
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• pp.120-125
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• 2000

연안역의 토지이용이 극대화됨에 따라 연안구조물이나 항만구조물의 축조가 활발히 진행되고 있다. 이를 설계하는데 있어서 무엇보다 중요한 것은 천해설계파 등과 같은 파랑변형계산을 얼마만큼 실현상과 근사시켜 재현할 수 있는지의 여부에 달려 있다. 지금까지의 천해설계파 산정에 있어서는 주로 단일 주파수와 단일 방향에 대한 규칙파해석이 수행되어져 왔으나, 실제해역에서의 파랑은 수많은 주파수와 파향, 파고들이 합성되어 이루어진 다방향 불규칙파랑이므로 실제 해역의 자연현상이 잘 표현되었다고 보기는 어렵다. (중략)

• Journal of the Society of Naval Architects of Korea
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• v.39 no.1
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• pp.38-48
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• 2002

Theoretical development to generate the directional extreme waves in model basin is established based on wave focusing method. The effects of associated parameters, such as the directional range, frequency width, and center frequency, are investigated in terms of wave focusing efficiency. The two different spectral models of constant wave amplitude and constant wave slope are applied to control the wave characteristics. The wave packets simulated by theory are compared with numerical results based on Boussinesq equation and FEM. Both controls of direction and frequency spectrum are essential to focus directional waves effectively. It is noticed that wave focusing ability depends on the frequency bandwidth of spectrum rather than center frequency, and both spectral models with same parameters result in the equivalent efficiency of wave focusing.

• The Academic Congress of Korean Shoulder and Elbow Society
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• 2000.03a
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• pp.80-80
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• 2000

• Journal of the Korea Society of Computer and Information
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• v.16 no.3
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• pp.99-107
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• 2011

The feature extraction of asterias amurensis by using patterns is difficult to extract all the concave and convex features of asterias amurensis nor classify concave and convex. Concave and convex as important structural features of asterias amurensis are the features which should be found and the classification of concave and convex is also necessary for the recognition of asterias amurensis later. Accordingly, this study suggests the technique to extract the features of concave and convex, the main features of asterias amurensis. This technique classifies the concave and convex features by using the multi-directional linear scanning and form the candidate groups of the concave and convex feature points and decide the feature points of the candidate groups and apply convex hull algorithm to the extracted feature points. The suggested technique efficiently extracts the concave and convex features, the main features of asterias amurensis by dividing them. Accordingly, it is expected to contribute to the studies on the recognition of asterias amurensis in the future.

• Journal of Korea Water Resources Association
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• v.42 no.3
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• pp.247-257
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• 2009

In this study, a distributed rainfall-runoff model is developed using a multi-directional flow allocation algorithm and the real-time runoff updating algorithm. The developed model consists of relatively simple governing equations of hydrologic processes in order to apply developed algorithms and to enhance the efficiency of computational time which is drawback of distributed model application. The variability of topographic characteristics and flow direction according to various spatial resolution were analyzed using DEM(Digital Elevation Model) data. As a preliminary process using fine resolution DEM data, a multi-directional flow allocation algorithm was developed to maintain detail flow information in distributed rainfall-runoff simulation which has strong advantage in computation efficiency and accuracy. Also, a real-time updating algorithm was developed to update current watershed condition. The developed model is able to hold the information of actual behavior of runoff process in low resolution simulation. Therefore it is expected the improvement of forecasting accuracy and computational efficiency.

• Journal of the Korea Society of Computer and Information
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• v.13 no.7
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• pp.109-115
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• 2008

In the P2P distributed system, such peers don't always keep on-line status. P2P systems are different from the ordinary systems that such peers are organically operated as the elements of system. In this case, users using P2P system are able to loss the reliability. At this point, many P2P studies are tried to resolve these problems. In this paper, we suggest a P2P search algorithm for multidirectional processing about the resources to be downloading. In existing studies, the loading rate is very high to select new resources supported peer, so we suggest new solution in this study.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.37 no.1
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• pp.35-44
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• 2001

A numerical procedure is described for simultaneously predicting the wave exciting forces and drift forces on a Tension Leg Platform (TLP) in multi-directional irregular waves. The numerical approach is based on a three dimensional source distribution method to the wave exciting forces, a far-field method to the steady drift forces and a spectral analysis technique of directional waves. The spectral description for the linear system of TLP in the frequency domain is sufficient to completely define the wave exciting forces and steady drift forces. This is because both the wave inputs and the outputs are stationary Gaussian random process of which the statistical properties in the amplitude domain are well known. Numerical results of steady drift forces are compared with the experimental and numerical ones, which are obtained in the literature. The results of comparison confirmed the validity of the proposed approach.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2014.06a
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• pp.79-80
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• 2014

본 논문에서는 다방향 패턴을 이용한 구조광(structured light)방식의 3차원 스캔 기법을 적용하여 3차원 스캐너의 3차원 형상 취득의 정밀도를 높이는 방법을 제안한다. 기존의 단방향 패턴을 이용한 3차원 구조광 방식의 스캔 기법으로 3차원 형상을 취득하는 경우, 스캔 대상 표면의 법선벡터가 패턴의 방향과 수평 할수록 부정확한 형상이 복원된다. 본 논문에서는 스캔 대상의 경사면에 따른 법선 벡터(normal vector) 검출 및 검출된 벡터를 통한 최적의 패턴 방향 선출(quantization), 그리고 각 화소의 최적의 패턴방향을 이용한 선별적인 구조광 방식의 3차원 스캔 기법을 통하여 3차원 형상 취득의 정확성을 높이는 기법을 제안한다.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2010.05a
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• pp.115-118
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• 2010

• Proceedings of the Korea Water Resources Association Conference
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• 1997.05a
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• pp.531-536
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• 1997