• 대한기계학회논문집B
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• 제20권1호
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• pp.255-265
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• 1996

Up to the present the study on the performance prediction of HAWT was performed mainly by assuming the axial flow. So in this paper we aimed at the fully non-axial flow of HAWT. For this purpose, we defined the wind turbine pitch angle in addition to the yaw angle to specify the arbitrary wind direction. And we adopted the Glauert method as the basic analysis method then modified this method suitably for our goal. By comparing the computational results obtained by this modified new Glauert method with the experimental results, it was proved that our method was a very efficient method. And on the basis of the reliability of this method we considered the effect of all the design parameters and presented the optimum blade geometry and the optimum operating condition to gain the best performance curve.

• Wind and Structures
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• 제14권1호
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• pp.1-14
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• 2011

Open frame structures, such as those commonly found in industrial process facilities, are often densely occupied with process related equipment. This paper presents a method for estimating wind loads for high-solidity open frame structures that differs from current approaches, which accumulate wind load contributions from various individual structure components. The method considers the structure as a porous block of arbitrary plan dimension that is subject to wind from any direction. The proposed method compares favorably with wind tunnel test results for similar structures. The possibility of defining an upper bound force coefficient is also discussed.

• 산업기술연구
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• 제14권
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• pp.39-48
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• 1994

Up to the present the study on the performance prediction of HAWT was perfomed mainly by assuming the axial flow. So in this paper we aimed at the fully non-axial flow of HAWT. For this purpose, we defined the wind turbine pitch angle in addition to the yaw angle to specify the arbitrary wind direction. And we adopted the Glauert method as the basic analysis method then modified this method suitably for our goal. By comparing the computational results obtained by this modified new Glaurert method with the experimental results, it was proved that our method was a very efficient method.

• 한국통신학회논문지
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• 제42권5호
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• pp.1085-1092
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• 2017

본 논문은 풍력발전예측의 정확도 개선을 위하여 바람의 특성을 반영한 풍력발전량예측 방법을 제안한다. 제안한 방법은 크게 바람의 특성을 추출하는 부분과 발전량을 예측하는 부분으로 구성된다. 바람의 특성을 추출하는 부분은 발전량, 풍향과 풍속의 상관분석을 이용한다. 풍향과 풍속의 상관관계를 근거로 K-means 방법으로 클러스터링하여 특징 벡터를 추출한다. 예측하는 부분은 임의의 실수값을 예측 할 수 있도록 SVM을 일반화 한 SVR을 이용하여 기계학습을 한다. 기계학습은 바람의 특성을 반영한 제안한 방법과 바람의 특성을 반영하지 않은 기존방법을 비교 실험하였다. 또한, 제안한 방법의 정확도와 타당성을 검증하기 위하여 장소가 상이한 제주도 풍력발전단지 3지역에서 수집된 데이터를 사용하였다. 실험결과, 제안한 방법의 오차가 일반적인 풍력발전예측 오차보다 개선되었다.

• 소음진동
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• 제11권2호
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• pp.329-335
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• 2001

The analytical model of the ground wave can be used for the prediction of the noise level from a source above a plain and homogeneous ground surface with no obstacles nearby. Sound propagation along the surface of the ground can be affected by the roughness of the ground surface and the direction of the wind. The effects of the ground surface and the wind can be formulated in terms of the ground coefficient and the noise source parameter. Upward and downward conditions can also be addressed by considering the direction of the wind. The ground coefficient and the noise source parameter are estimated using the measured noise levels of two points under particular environmental condition, and the noise levels of arbitrary points under the same environmental condition can be estimated. The proposed method can be utilized to estimate the noise level of specific noise environment and its validity was confirmed with the results of actual field measurement.

• 한국해양공학회지
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• 제16권2호
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• pp.10-20
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• 2002

본 논문에서는 바다의 자유표면에서 생성되는 항력에 대한 물리적 특성에 대한 연구가 기술되었다. 2차원 파장(Wave Field) 매개변수해석기법(Parametric Analyzing Technique)을 근거로 한 파경계층(Wave Boundary Layer : WBL)의 1차원 모델로서 항력계산과 파경계층의 특성을 추정하였으며 이론의 간략화(Simplifying)에 대한 연구에 주력하였다.

• 한국공간구조학회논문집
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• 제8권5호
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• pp.95-105
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• 2008

본 논문에서는 케이블-막구조의 요소이동을 고려한 해석 기법을 제시하기 위하여 초기평형형상해석 및 응력해석과 요소이동성을 고려한 해석으로 구분하여 연구함으로서 이론적인 접근을 통해 요소이동성을 평가하였으며, 요소이동을 고려한 해석으로 ALE(Arbitrary Lagrangian-Eulerian) 유한요소법을 이용하여 작성된 알고리즘을 제시하여 다양한 예제의 검증을 통해 제안방법을 평가하였다.

• Wind and Structures
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• 제15권3호
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• pp.189-208
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• 2012

Lock-in and drag amplification phenomena are studied for a flexible cantilever using a simplified fluid-structure interaction approach. Instead of solving the 3D domain, a simplified setup is devised, in which 2D flow problems are solved on a number of planes parallel to the wind direction and transversal to the structure. On such planes, the incompressible Navier-Stokes equations are solved to estimate the fluid action at different positions of the line-like structure. The fluid flow on each plane is coupled with the structural deformation at the corresponding position, affecting the dynamic behaviour of the system. An Arbitrary Lagrangian-Eulerian (ALE) approach is used to take in account the deformation of the domain, and a fractional-step scheme is used to solve the fluid field. The stabilization of incompressibility and convection is achieved through orthogonal quasi-static subscales, an approach that is believed to provide a first step towards turbulence modelling. In order to model the structural problem, a special one-dimensional element for thin walled cross-section beam is implemented. The standard second-order Bossak method is used for the time integration of the structural problem.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2000년도 춘계학술대회논문집
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• pp.1865-1870
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• 2000

Sound propagation along the surface of the ground can be affected by the roughness of the ground surface and the direction of the wind. Noise Source parameter and ground factor are estimated using the measured results of two points under particular environmental condition, and the noise level of arbitrary points under the same environmental condition can be estimated. The results can be used for the prediction of the noise level from a source above a plain and homogeneous ground surface with no obstacles nearby. Upward and downward conditions are also addressed in addition to ground effect. The proposed method can be utilized to estimate the noise level of specific noise environment and its validity was confirmed with the results of actual field measurement.

• International Journal of Ocean Engineering and Technology Speciallssue:Selected Papers
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• 제5권1호
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• pp.29-39
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• 2002

A general investifation into the physical mechanism that is respinsible for drag above the sea surface has been undertaken. On the basis of a ID model of the Wave Boundary Layer(WBL), under a 2D wave field, a parameterization technique for estimation of the drag and mean characteristics of WBL is described. Special attention is paid to estimation of the simplifying assumption of the theory.