• Ocean and Polar Research
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• 제43권2호
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• pp.53-63
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• 2021

Changes in a marine environment have a broad socioeconomic implication on fisheries and their relevant industries so that there has been a growing demand for the medium-range (months to years) prediction of the marine environment Using a medium-range ocean prediction model (Ocean Mid-range prediction System, OMIDAS) for the northwest Pacific, this study attempted to assess seasonal difference in the mid-range predictability of the sea surface temperature (SST), focusing on the Korea seas characterized as a complex marine system. A three-month re-forecast experiment was conducted for each of the four seasons in 2016 starting from January, forced with Climate Forecast System version 2 (CFSv2) forecast data. The assessment using relative root-mean-square-error was taken for the last month SST of each experiment. Compared to the CFSv2, the OMIDAS revealed a better prediction skill for the Korea seas SST, particularly in the Yellow sea mainly due to a more realistic representation of the topography and current systems. Seasonally, the OMIDAS showed better predictability in the warm seasons (spring and summer) than in the cold seasons (fall and winter), suggesting seasonal dependency in predictability of the Korea seas. In addition, the mid-range predictability for the Korea seas significantly varies depending on regions: the predictability was higher in the East Sea than in the Yellow Sea. The improvement in the seasonal predictability for the Korea seas by OMIDAS highlights the importance of a regional ocean modeling system for a medium-range marine prediction.

• 해양환경안전학회지
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• 제21권5호
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• pp.543-551
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• 2015

본 논문에서는 교량, 선박 등에 사용하고 해양환경을 고려한 알루미늄 합금(A6082-T-6) 플레이트 거더의 물리적 관계를 살펴보고자 한다. 플레이트 거더는 제품수명주기에 이동하중, 적재하중 등 같은 패치로딩을 경험하게 된다. 이 하중을 받는 알루미늄합금 플레이트 거더의 최종강도에 대해 다수 수치모형을 적용하여 탄소성 대변형 시리즈 해석을 수행하고 회귀분석을 통해 예측식을 제안하였다. 예측식은 최종강도와 세장변수의 상관관계로 나타냈으며 세장변수가 낮을 경우(0-2.3) 약 9 % 정도 오차가 발생하며 높을 경우(2.3-4.0) 약 1-2 % 정도 오차가 발생하였다. 따라서 제안 예측식 적정성은 합리적으로 평가할 수 있는 것으로 확인되었다.

• International Journal of Naval Architecture and Ocean Engineering
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• 제11권2호
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• pp.765-781
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• 2019

This study predicts the power consumption of an Electric Propulsion Ship (EPS) in marine environment. The EPS is driven by a propeller rotated by a propulsion motor, and the power consumption of the propeller changes by the marine environment. The propulsion motor consumes the highest percentage of the ships' total power. Therefore, it is necessary to predict the power consumption and determine the power generation capacity and the propeller capacity to design an efficient EPS. This study constructs a power estimation simulator for EPS by using a ship motion model including marine environment and an electric power consumption model. The usage factor that represents the relationship between power consumption and propulsion is applied to the simulator for power prediction. Four marine environment scenarios are set up and the power consumed by the propeller to maintain a constant ship speed according to the marine environment is predicted in each scenario.

• 해양환경안전학회:학술대회논문집
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• 해양환경안전학회 2017년도 추계학술발표회
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• pp.2-2
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• 2017

• 환경영향평가
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• 제21권5호
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• pp.767-779
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• 2012

In case of executing surveys in marine ecosystems, the most important things are scientific selection measures of survey stations that can represent various ecosystems characteristics in subjected areas. The situations show a lot of differences that understand characteristics of marine ecosystems in targeted areas according to selection methods and positions in survey stations. Investigation ranges and station numbers in marine ecosystems are classified according to project characteristics and scales. But, currently a clear divisions or objective standards are not. Therefore, this study tried to provide selection measures of survey station in scientific and objective marine ecosystems through precise analysis among environmental impact statements of coastal development projects until now. In this study, impact scopes of marine ecosystems correspond to physical impact predictions by undertaking projects. Impact ranges were divided into three(physical impact ranges) coastal waters. In case of proposing numbers of survey stations according to this survey ranges, numbers of investigation stations due to minimum survey scopes in targeted projects applied 20~30% of all numbers in survey stations. Number of survey stations due to average investigation scopes within physical impact ranges applied 60~70% of all numbers in investigation stations. Numbers of survey stations due to maximum survey ranges within physical impact scopes applied 10~20% of all numbers in survey stations. So, improvement measures were deducted. Finally, according to prediction ranges in impact of various coastal development projects, several kinds of conclusions are suggested. And, it is thought to be able to use as fundamental database to select investigation stations in marine organisms through this study.

• Journal of Advanced Marine Engineering and Technology
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• 제41권1호
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• pp.56-61
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• 2017

본 논문은 시간지연이 있는 데이터의 예측기법과 햅틱기반의 원격조작시스템에서의 응용방법을 다룬다. 일반적으로 네트워크 환경은 데이터 전송에 따른 시간지연이 필수적으로 동반되며, 햅틱기반의 원격조작시스템이 이러한 네트워크 환경에 구현되는 경우 시간지연으로 인해 전체 시스템의 성능저하를 피할 수 없다. 이러한 상황을 고려하여, 본 논문은 ARMA모델을 기반으로 모델파라미터의 학습방법과 실시간 예측을 위한 재귀적 알고리즘을 제안한다. 제안된 방법은 가상공간에 놓인 물체에 대하여 양방향 햅틱 상호작용의 상황에서 5ms의 샘플링 주기로 획득한 햅틱데이터에 적용되며, 그 결과로서 100ms 이후의 값을 예측함에 있어 위치수준 오차 1mm이내의 예측성능을 보였다.

• 한국환경과학회지
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• 제14권8호
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• pp.777-783
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• 2005

For the sustainable management of marine ecosystem in Masan Bay, we have to assess the carrying capacity and standard of target water quality. In this research, we assume that all pollutants loads are treated in Dukdong sewage treatment plant, then we simulate the physical-biological model for prediction water quality for the achievement of standard water quality. In 2001 year, for the achievement of COD 2.5 mg/L, we need to reduce COD $90\%$, nitrogen $30\%$, phosphate $90\%$ than that of the present value, According to these results, the water quality of sewage treatment plant is required to treat COD 13.5 mg/L, nitrogen 33.3 mg/L, phosphate 6,0 mg/L. If the sewage treatment plant will be expanded much larger in 2011, it will need to be treated in COD 6.6 mg/L, nitrogen 2.5 mg/L, phosphate 5 mg/L for the achievement of water quality standard in COD 2.5 mg/L.

• Computers and Concrete
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• 제15권4호
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• pp.589-606
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• 2015

It is well-documented that the major deterioration of coastal RC structures is chloride-induced corrosion. Therefore, regional investigations are necessary for durability based design and evaluation of the proposed service life prdiction models. In this paper, four reinforced concrete jetties exposed to severe marine environment were monitored to assess the long term chloride penetration at 6 months to 96 months. Also, some accelerated durability tests were performed on standard samples in laboratory. As a result, two time-dependent equations are proposed for basic parameters of chloride diffusion into concrete and then the corrosion initiation time is estimated by a developed probabilistic service life model Also, two famous service life prediction models are compared using chloride profiles obtained from structures after about 40 years in the tidal exposure conditions. The results confirm that the influence of concrete quality on diffusion coefficients is related to the concrete pore structure and the time dependence is due to chemical reactions of sea water ions with hydration products which lead a reduction in pore structure. Also, proper attention to the durability properties of concrete may extend the service life of marine structures greater than fifty years, even in harsh environments.

• 한국해양환경ㆍ에너지학회지
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• 제13권4호
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• pp.234-240
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• 2010

연안개발로 인해 발생하는 해양환경 변화를 정확히 예측하여 해양환경을 효율적으로 관리하기 위해서는 정확한 조위 및 조류 분포에 관한 자료의 확보가 필수적이다. 그러나 현재 대부분의 환경영향평가에서는 조석 수치모의에서 제한된 조석분조 만을 사용하여 조위와 조류분포를 예측하여 많은 분조의 합성에 의해 발생되는 실제 조석현상을 정확하게 계산하지 못하고 있으며, 이로 인해 환경영향평가에 오류가 발생하고 있다. 본 연구에서는 제한된 분조의외해 개방경계에서 조화상수를 가지고도 연안에서 관측된 조위자료를 활용하여 실시간으로 정확하게 조위 및 조류 분포를 예측할 수 있는 방법을 제안하였다. 4개 분조에 의한 조위와 38개 분조에 의한 조차의 비 그리고 모의조차와 관측조차의 비를 가지고 보정한 조위 예측결과는 관측조위와 잘 일치하였다.

• 한국해양환경ㆍ에너지학회지
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• 제16권3호
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• pp.211-216
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• 2013

대부분의 사고선박 예인력 계산을 위한 선체저항 성능 추정은 매우 간단하고 오래된 방법을 사용하고 있는데, 특히 바지선의 경우는 미국 해군 예인 매뉴얼에서 사용하는 방법과 유사한 방법을 사용하고 있다. 본 논문에서는 미국 해군 예인 매뉴얼 방법과 국내 해양수산부 고시 방법을 검토한 결과, 이는 비합리적이고 부정확한 추정 방법임을 밝혔다. 나아가, 바지선에 적용할 수 있는 합리적이고도 정확한 저항 성능 추정 방법으로 새로운 Modified-Yamagata-Barge 방법을 도출하였다.