• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 2008년도 춘계종합학술대회 A
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• pp.1003-1007
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• 2008

HF대 SSB 해상 데이터통신 서비스를 운용하는 회사는 가입 선박을 대상으로 하지만, 무선프로토콜의 미비로 접속을 요구하는 선박이 많아지면 calling redundancy가 증가되는 문제가 있다. 선박국과 링크접속을 위하여 자유신호를 이용하는 경우가 있지만 선박국들의 호출에 의한 서로간의 충돌을 회피하기가 어렵다. HF대 SSB 통신은 특성상 채널의 트래픽을 고려하여 자동적으로 무선링크가 설정되어야 하며, 트래픽의 과부하시에는 적응적으로 채널의 안정성을 확보하며 운용되어야 한다. 이에 대하여 자유접속, 그룹자유접속, 폴링(polling)의 3가지 접속링크 방식을 순차적으로 구동하는 새로운 무선프로토콜에 대하여 연구하였다

• 한국지능시스템학회논문지
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• 제25권3호
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• pp.293-298
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• 2015

해상교통상황에서 수집된 선박 조우(Encounter) 데이터 변수는 선박 충돌 및 근접사고(Near-Collision) 위험도를 통계적인 방법에 의한 분석이 가능하다. 본 연구에서는 선박 조우 데이터에서 추출되는 다수의 선박충돌위험도 평가 변수들을 요인분석(Factor Analysis)하여, 선박 조우데이터에서 충돌위험에 영향을 미치는 주요 요인을 결정하고자 한다. 각 요인 결정을 위해 선박조우데이터 변수 정규분포화 및 표준화를 수행한 후 주성분 분석(Principal Component Analysis)으로 요인을 결정하였다. 요인분석결과 선박 근접도 요인과 충돌회피변화요인으로 요약하였다.

• 수산해양교육연구
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• 제25권2호
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• pp.393-404
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• 2013

In order to improve the employment rate of graduates in maritime and fisheries high schools, we investigated the employment situations of the those graduates for the last 8 years. The results were as follows, The ratio of graduates in maritime and fisheries high schools to total graduates of on-board departments are 69.1% and 30.9% respectively. The on-board employment rate of maritime high schools and fisheries high schools graduates are 63.2% and 26.7% respectively. Nearly all of the maritime high schools students were employed to merchant ship and fisheries high schools students were employed to merchant ship 77.2% and only 22.8% of them got a job on fisheries ship. The ratio of getting a job in maritime high schools to ocean-going ship was 76.7%, that was the highest ratio and the ratio of fisheries high schools got a job to ocean-going ship was 55.1%. The on-board career of maritime high schools graduates was 1~5 years, which took 86.4% of all careers and that of fisheries high schools was less than 1 year, which took 60.0% of all careers. We should make the various efforts to improve the employment rate of getting job to fisheries ship in the fisheries high school graduates.

• 대한조선학회논문집
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• 제45권3호
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• pp.329-336
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• 2008

Basic performances of wireless sensor network (WSN) and power line communication (PLC) confirmed in the test bed ashore are investigated in the 3000-ton class training ship of Korea Maritime University. The ubiquitous technologies can be considered for the provision of safety and convenience in a ship. We employed WSN and PLC, as the ubiquitous technologies, at the two areas within the training ship to estimate the realization of the ubiquitous environments in a ship. The experiments show rather good results in terms of data transfer rate. However, more detailed studies concerning the connection between WSN and PLC, noises induced to power line and fading effects are required to improve the quality and the stability of the communication for the ubiquitous environments.

• 해양환경안전학회지
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• 제25권3호
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• pp.320-327
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• 2019

The purpose of this paper is to compare seafarers' behavior according to traffic conditions of a road and an onshore locations. Behaviors are classified into three categories: Skill-, Rule- and knowledge-based mode. Experimental data were collected using the questionnaires for navigators, working in a merchant ship. To compare the behaviors, we used the four analysis method; the degree of frequency, reliability test, correlation and linear regression. As a result of the study, it was found that Skill-based behavior shows more higher in the road traffic than the maritime traffic, and rule-based behavior shows more higher in the maritime traffic than the road traffic. Also, the behavior in the navigation situation showed statistical significance. Especially, in the case of Rule-based behavior, a high correlation between road and maritime was found. This study can be expected to apply to complementary system utilization between error management system of onshore and maritime traffic.

• 한국항해항만학회지
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• 제46권2호
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• pp.92-98
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• 2022

Maritime accidents result in enormous economic loss and loss of life; thus, such accidents must be prevented, and risks must be managed to prevent these occurrences Risk management must be based on statistical evidence such as variables. Because calculating when variables increase statistically can be difficult, compressing the designated variables is necessary to use the maritime accident data in Korea. Thus, in this study, variables of marine accident data are compressed using statistical methods. The date, ship type, and marine accident type included in all maritime accident data were extracted, the number of optimal variables was confirmed using the hierarchical clustering analysis method, and the data were compressed. For the compressed variables, the validity of the data use was statistically confirmed using analysis of variance, and the data of the variables identified using the variable compression method were designated. Consequently, among the monthly and yearly data, statistical significance was confirmed in yearly data, and compression was possible. The significance of the data was confirmed in six and eight types of ships and accidents, respectively, and these were compressed. These results can be directly used for prevention or prediction based on past maritime accident data. Additionally, the data range extracted from past maritime accidents and the number of applicable data will be studied in the future.

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2012년도 춘계학술대회
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• pp.125-126
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• 2012

부산은 세계 3위의 최대 컨테이너 항만시설과 물류시스템을 갖추고 있는 해양도시이지만, 부산시민의 해양의식은 이에 미치지 못하고 있다. 이에 부산지역 해양교육의 현황을 분석하여, 부산지역 해양교육의 문제점을 분석하고 이를 활성화시킬 수 있는 방안을 제시하였다. 이를 통해 부산시가 해양도시로써 명성을 이어가고 건전한 친수문화의 조성과 해양문화를 널리 전파할 수 있을 것이다.

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2012년도 추계학술대회
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• pp.58-59
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• 2012

우리나라는 해양강국으로서 입지를 유지하기 위해 해양교육의 중요성을 강조하고 있지만 구체적인 해양교육 프로그램의 운영을 위한 체계가 빈약한 실정이다. 이에 국내 외 해양교육의 프로그램을 분석하여 우리나라의 환경에 맞는 해양교육을 표준화하여, 교육의 효과를 극대화할 수 있는 해양교육 모듈 및 해양교육코스를 개발하였다.

• Journal of electromagnetic engineering and science
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• 제5권3호
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• pp.117-121
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• 2005

We compared electromagnetic(EM) wave absorption properties between Alnico magnet (A) and (B) with different magnetic properties. Also, we investigated the effect of carbon, thickness of absorbers, and Alnico contents on EM wave absorption, and clarified the relation between Alnico content and central frequency.

• 해양환경안전학회:학술대회논문집
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• 해양환경안전학회 2018년도 공동국제학술발표회
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• pp.199-199
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• 2018