• 한국항해항만학회지
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• 제26권2호
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• pp.221-226
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• 2002

표류지점 추정 모델의 환경 입력자료를 확보하기 위해 부산항 연근해에서 표류실험을 실시하였다. 실험에는 크기가 다른 4척의 선박(10, 20, 50, 90톤급)이 사용되었다. 그중 50톤급 선박에는 해류, 바람, 위치를 자동적으로 기록하는 계기들을 장착하였고, 나머지 선박들에서는 분산각 추정 연구를 위해 위치자료만 기록하였다. 각 선박들의 위치는 DGPS와 자동위치발신기(APRS)를 사용하여 기록하였다. 실험은 풍속 2~10m/s, 유속 0.5~1.5m/s의 환경에서 행하여졌으며, leeway는 선박 표류속도에서 표층의 유속성분을 제거하여 구하였다. 50톤급 선박의 leeway rate는 풍속의 약 3.6%인 것으로 분석되었으며, leeway 방정식은 $U_L$ =0.042W -0.034로 표현되었고 leeway angle은 $-30^{\circ}$~$40^{\circ}$의 범위였다.

• 해양환경안전학회지
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• 제7권2호
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• pp.13-22
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• 2001

We studied the characteristics of marine casualties within the area under control of Korea National Maritime Police and leeway of drifting vessel. According to 5 years＇(1995~1999) data of casualties, it was found that the occurrence of casualties by fishing boats ranked the highest and a considerable numbers of casualties took place more than 20 miles off the shore. From a result of field experiment of G/T 50 tons vessel off Busan harbor on Apr. 26~28, 2000, we computed that the linear equation of leeway speed(cm/s) was 1.01$\times$U(U : wind speed in m/s)+11.36 with correlation coefficient between wind speed and leeway speed being 0.252 and we found leeway angle range from $+87^{\circ}$(right) to $-78^{\circ}$(left ) of the downwind direction.

• 수산해양기술연구
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• 제57권3호
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• pp.236-245
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• 2021

In this study, a drifting test using a experimental vessel (2,966 tons) in the northern waters of Jeju was carried out for the first time in order to obtain the fundamental data for drift. During the test, it was shown that the average leeway speed and direction by GPS position were 0.362 m/s and 155.54° respectively and the leeway rate for wind speed was 8.80%. The analysis of linear regression modes about leeway speed and direction of the experimental vessel indicated that wind or current (i.e. explanatory variable) had a greater influence upon response variable (e.g. leeway speed or direction) with the speed of the wind and current rather than their directions. On the other hand, the result of multiple regression model analysis was able to predict that the direction was negative, and it was demonstrated that predicted values of leeway speed and direction using an experimental vessel is to be more influential by current than wind while the leeway speed through variance and covariance was positive. In terms of the leeway direction of the experimental vessel, the same result of the leeway speed appeared except for a possibility of the existence of multi-collinearity. Then, it can be interpreted that the explanatory variables were less descriptive in the predicted values of the leeway direction. As a result, the prediction of leeway speed and direction can be demonstrated as following equations. Ŷ₁= 0.4031-0.0032X₁+0.0631X₂-0.0010X₃+0.4110X₄ Ŷ₂= 0.4031-0.6662X₁+27.1955X₂-0.6787X₃-420.4833X₄ However, many drift tests using actual vessels and various drifting objects will provide reasonable estimations, so that they can help search and rescue fishing gears as well.

• 해양환경안전학회지
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• 제1권1호
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• pp.1-8
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• 1995

해난사고의 발생으로 표류중인 조난선박을 구조하는데 있어서 가장 중요한 작업은 조난선박의 현재 표류위치를 정확하게 추정하는 것이다. 표류지점을 예측하는데 현재 사용되고 있는 방법들은 기본적으로 해류와 바람의 영향을 벡터적으로 합성하여 수색범위를 결정한다. 여기서 해류보다 바람의 영향에 의한 표류(leeway)를 예측하기가 어려운데 leeway는 주로 실물을 이용한 현장실험을 통하여 결정한다. 본 연구에서는 우리나라의 연안용 소형선박을 대상으로 제주 북방해역에서 실제 표류실험을 하였는데, leeway 산출에는 지금까지의 기법과는 달리 표류선박에서 측정된 상대유속과 유향 그리고 상대풍속과 풍향을 사용하였다. 실험자료로부터 산출된 leeway는 풍속의 약3% 부근이며 leeway angle은 자료중 80%가 -65˚에서 -15˚사이였다.

• 한국해양공학회지
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• 제37권4호
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• pp.145-157
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• 2023

Due to a recent increase in maritime activities in South Korea, the frequency of maritime distress is escalating and poses a significant threat to lives and property. The aim of this study was to validate a drift trajectory prediction technique to help mitigate the damages caused by maritime distress incidents. In this study, OpenDrift was verified using satellite drifter data from the Korea Hydrographic and Oceanographic Agency. OpenDrift is a Monte-Carlo-based Lagrangian trajectory modeling framework that allows for considering leeway, an important factor in predicting the movement of floating marine objects. The simulation results showed no significant differences in the performance of drift trajectory prediction when considering leeway using four evaluation methods (normalized cumulative Lagrangian separation, root mean squared error, mean absolute error, and Euclidean distance). However, leeway improved the performance in an analysis of location prediction conformance for maritime search and rescue operations. Therefore, the findings of this study suggest that it is important to consider leeway in drift trajectory prediction for effective maritime search and rescue operations. The results could help with future research on drift trajectory prediction of various floating objects, including marine debris, satellite drifters, and sea ice.

• 한국항만학회지
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• 제12권2호
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• pp.373-384
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• 1998

In search and rescue mission the leeway formula based on the field experiments are utilized for the estimation of wind effect on distressed targets. This paper summarized the leeway formula from the available references. In the summary the environmental data collection method and experimental conditions are described along with the formula. Also the formula currently used in CASP of the U.S. Coast Gurard and CANSARP of the Canadian Coast Guard are discussed.

• 대한치과의사협회지
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• 제11권11호
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• pp.763-768
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• 1973

• 대한치과의사협회지
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• 제21권10호통권173호
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• pp.821-828
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• 1983

• 수산해양기술연구
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• 제58권4호
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• pp.299-309
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• 2022

Among the fishing vessels operating in the coastal waters, jigging fishing vessels were considered representative vessels engaged only by wind, sea, tide, and external force. Then, a fishing vessel with a length of shorter than 10 m from July 1, 2018 to August 5, 2019 was studied to obtain a drift prediction model by multiple regression analysis. In the correlation analysis between variables for leeway of speed and direction, the speed and direction of tidal seem to be the most affected in coastal waters. Therefore, it should be considered an explanatory variable when conducting drift tests. As a result of multiple regression analysis on the predicted equations of leeway speed and direction due to the external force on the drift of the fishing vessel, p < 0.000 was considered significant in the F-test, but the coefficient of determination was 55.2% and 37.8%. The effect on the predicted leeway speed was in the order of the tidal speed and current speed. In addition, the impact on the predicted leeway direction was in the order of the tidal speed and current speed. ŷ(m/s) = - 0.0011(x1) + 0.9206(x2) + 0.0001(x3) + 0.0002(x4) + 0.0050(x5) + 0.0529(x6) + 0.2457 ŷ(degree) = 0.6672(x1) + 93.1699(x2) + 0.0585(x3) - 0.0244(x4) - 1.2217(x5) + 4.6378(x6) - 0.0837

• 한국항해항만학회지
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• 제26권5호
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• pp.491-495
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• 2002

수색구조 작업에서 표류지점 추정 모델을 윈도우 운영체계에서 쉽게 운영할 수 있는 GUI 프로그램을 개발하였다. 운영자가 화면의 선택사항을 보고 표류물체의 종류와 해상환경 조건을 입력시킬 수 있도록 하였고, 계산된 추정 점 및 선박의 표류 궤적이 좌표와 함께 전자해도상에 표시되게 하여 현장에서 쉽게 예측결과를 알 수 있도록 하였다. 프로그램에는 Leeway공식을 사용하는 방식과 Newton의 운동방정식에서 해를 구하는 방식을 사용하였다. 프로그래밍에 사용된 언어는 FORTRAN이고, 그래픽 처리를 위해 Lahey의 Winteracter 4.0을 활용하였다. 모델의 시연을 위해 2001년 5월 부산 근해에서 수행된 현장실험 결과와 예측 모델에 의한 결과를 비교·도시하였다.