• 대한전기학회:학술대회논문집
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• 대한전기학회 2002년도 하계학술대회 논문집 C
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• pp.1698-1700
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• 2002

Recently, the HFPD measurement methods that detect high frequency bandwidth of frequency components of partial discharge pulses are proposed and many studies are carried out. The HFPD measurement method is able to detect partial discharge signal in active line, therefore this method has a merit that can does condition monitoring of power equipments and measure growth state of partial discharge erosion with on-line and real time. In this study, the radiated HFPD signals are detected by antenna and aging diagnosis is executed with a neural network algorithm. As a result of this study, the aging diagnosis of insulation material using neural networks is possible.

• 수산해양교육연구
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• 제6권2호
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• pp.198-216
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• 1994

The problem of promoting instructional effect using reorganizing the content of textbook is one of the major concerns of many education theorists and teachers. The results of many researches about above problem reveal that reorganizing the content of textbook promotes the ability of recall and problem solving of learners. The content structure of current navigation textbook revealed a categorical structure as its basic framework, though it seems to be a poor one. A categorical structure is known as providing an inferior information processing mechanism for learners than a learning hierarchy content structure is. Furthermore current content structure hasn't given any considerations to navigation in practice, spatial contexts and sequential events of ships from a harbor to another harbor. The learning hierarchy content structure has an advantage of giving learners more systematic and stronger knowledge networks than a categorical structure.

• Journal of Communications and Networks
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• 제18권3호
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• pp.311-319
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• 2016

In this paper, we analyze the spectrum-sensing performance of a cooperative cognitive radio (CR) network consisting of a number of CR nodes and a fusion center (FC). We introduce the "log-average-SNR ratio" that relates the average SNR of the CR-node-FC link and that of the primary-user-CR-node link. Assuming that the FC utilizes the K-out-of-N rule as its decision rule, we derive exact expressions for the sensing gain and the coding gain - parameters used to characterize the CR network performance at the high SNR region. Based on these results, we determine ways to optimize the performance of the CR network.

• 한국항해항만학회지
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• 제36권2호
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• pp.131-140
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• 2012

Since 2000, S. Korea is building yachts through government supported localization, cooperation between industry and educational organizations, or partnerships with foreign firms but the yacht building has yet only accomplished trial manufactured ships and one-time production. Because of a lack of mass production, the industry assesses the domestic technical skills to an average 50~60% of developed countries and its market share is less than 1% in the world. In addition, domestic marine equipment is heavily depending on imports and the industry is experiencing shortage of technology and experts, small-sized companies, insufficient industry and educational organizations' cooperation networks, inadequate legislation and policies, deficient domestic market vitalization, and scarce international information. Thus, this study focuses on the alternative plans to strengthen competitiveness and to cope with problems in the southeast marine leisure equipment industry.

• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 2006년도 춘계종합학술대회
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• pp.228-231
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• 2006

선박의 위치추적시스템(VMS: Vessel Monitoring System)은 선박의 안전항해를 확보하기 위한 수단으로 다양한 통신망을 사용하여 구성을 확대해나가고 있다. VMS를 위한 통신망으로는 현재 Inmarsat 및 Orbcomm 등 위성통신망과 AIS(Automatic Identification System of ships: 선박자동식별장치)의 VHF(Very High Frequency: 초단파) 통신망 등이 사용되고 있다. 최근에는 5톤 이상의 어선에도 VHF 무선설비의 설치를 단계적으로 강제화하였으며, 소형선박에도 AIS의 탑재를 강제화할 계획을 검토하고 있음에 따라 이에 따른 효율적인 통신망 구축 방안을 사전에 검토할 필요성이 대두되었다. 여기에서는 선박의 안전항해를 확보하고 효율적인 VMS를 구축할 수 있는 VMS 통신망 구축 방안에 대하여 연구 제시하였다.

• 한국정보처리학회:학술대회논문집
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• 한국정보처리학회 2014년도 추계학술발표대회
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• pp.561-563
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• 2014

애드혹 네트워크(Ad Hoc Network)는 최근 이슈가 되고 있는 사물 간 인터넷(Internet of Things), 스마트그리드(Smart Grid), 사람 중심 도시 센싱(People-Centric Urban Sensing), 해상 통신(Maritime Communications) 환경에서 다양하게 활용되는 네트워크 구조다. 이러한 환경에서의 애플리케이션들은 사용자들에게 다양한 편의성을 제공하기 위하여 사용자의 민감한 프라이버시 정보를 요구하기도 한다. 하지만, 만약 수집되어지는 프라이버시 정보가 인가되지 않은 공격자에게 노출된다면, 사용자는 불안함을 호소할 수 있을 것이고, 동시에 해당 데이터를 수집하고자 했던 서비스제공자는 경제적으로 커다란 손실을 입을 수 있다. 이러한 프라이버시 정보 노출을 방지하기 위하여 안전한 데이터 수집 기법들이 연구되어 왔다. 하지만, 대부분의 기법들은 기밀성만 제공할 뿐, 부인방지 및 익명성은 제공하지 않는다. 그리고 더 나아가 기존 기법들은 통계정보 수집과 개별적인 정보 수집을 동시에 제공하지 않는다. 본 논문은 개별정보수집 및 통계정보 수집을 모두 지원하며 동시에, 사용자에게 강화된 익명성 개념인 비연결성을 제공하는 새로운 데이터 수집 기법을 소개한다.

• Journal of Advanced Marine Engineering and Technology
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• 제20권3호
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• pp.286-286
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• 1996

A neural predictive tracking system for the control of structure-unknown dynamic system is presented. The control system comprises a neural network modelling mechanism for the the forward and inverse dynamics of a plant to be controlled, a feedforward controller, feedback controller, and an error prediction mechanism. The feedforward controller, a neural network model of the inverse dynamics, generates feedforward control signal to the plant. The feedback control signal is produced by the error prediction mechanism. The error predictor adopts the neural network models of the forward and inverse dynamics. Simulation results are presented to demonstrate the applicability of the proposed scheme to predictive tracking control problems.

• Journal of Advanced Marine Engineering and Technology
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• 제20권3호
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• pp.154-161
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• 1996

A neural predictive tracking system for the control of structure-unknown dynamic system is presented. The control system comprises a neural network modelling mechanism for the the forward and inverse dynamics of a plant to be controlled, a feedforward controller, feedback controller, and an error prediction mechanism. The feedforward controller, a neural network model of the inverse dynamics, generates feedforward control signal to the plant. The feedback control signal is produced by the error prediction mechanism. The error predictor adopts the neural network models of the forward and inverse dynamics. Simulation results are presented to demonstrate the applicability of the proposed scheme to predictive tracking control problems.

• 한국항해항만학회지
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• 제29권10호
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• pp.891-896
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• 2005

전국적으로 도로망이 확충되고 소득증대와 함께 주5일 근무제가 실시되면서 수상레저에 대한 국민의 관심이 증대되고 수상레저스포츠의 활동인구가 증가하는 추세에 있다. 그러나 수상레저활동과 관련된 사고도 증가하고 있어 이를 어떻게 예방할 것인가 하는 것에 대해서 많은 논의가 되고 있다. 그 일환으로 1999년에 수상레저안전법이 제정되었고, 2005년에는 전면 개정이 이루어졌다. 이에 따라 수상레저안전의 발전적인 방향을 모색하기 위해서는 수상레저인구를 대상으로 수상레저활동의 현황을 파악하고 수상레저안전법에 관련한 의식실태를 파악할 필요성이 있다. 이를 위해 수상레저활동자를 대상으로 개정된 수상레저안전법의 규제를 중심으로 설문분석을 실시하여 빈도분석과 교차분석 등을 통해 상호변수간의 연관정도와 상관관계 등을 분석하였다. 그 결과, 수상레저활동자들 중 $60\%$ 이상이 등록, 안전교육, 보험, 안전검사에 대해 각각 필요하다고 인지하고 있으며, 공통적으로 기구의 안전성에 대한 불만과 보험의 필요성에 대한 인지도가 높을수록 법적규제가 필요하다고 생각하는 경향이 있음을 확인할 수 있었다.

• Strategy21
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• 통권37호
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• pp.104-143
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• 2015

China's new grand strategy, the "One Belt, One Road Initiative" (also Belt Road Initiative, or BRI) has two primary components: Chinese President Xi Jinping announced the "Silk Road Economic Belt" in September 2013 during a visit to Kazakhstan, and the "21^st Century Maritime Silk Route Economic Belt" in a speech to the Indonesian parliament the following month. The BRI is intended to supply China with energy and new markets, and also to integrate the countries of Central Asia, the Association of Southeast Asia Nations (ASEAN), and the Indian Ocean Region - though not Northeast Asia - into the "Chinese Dream". The project will be supported by the Asian Infrastructure Investment Bank (AIIB), due to open in 2016 with 57 founding members from all around the world, and China has already promised US$ 50 billion in seed funding. China's vision includes networks of energy pipelines, railways, sea port facilities and logistics hubs; these will have obvious commercial benefits, but also huge geopolitical significance. China seems to have two distinct aims: externally, to restore its historical sphere of influence; and internally, to cope with income inequalities by creating middle-class jobs through enhanced trade and the broader development of its economy. In South Korea, opinion on the BRI is sharply polarized. Economic and industrial interests, including Korea Railroad Corporation (KORAIL), support South Korean involvement in the BRI and closer economic interactions with China. They see how the BRI fits nicely with President Park Geun-hye's Eurasia Initiative, and anticipate significant commercial benefits for South Korea from better connections to energy-rich Russia and the consumer markets of Europe and Central Asia. They welcome the prospect of reduced trade barriers between China and South Korea, and of improved transport infrastructure, and perceive the political risks as manageable. But some ardently pro-US pundits worry that the political risks of the BRI are too high. They cast doubt on the feasibility of implementing the BRI, and warn that although it has been portrayed primarily in economic terms, it actually reveals a crucial Chinese geopolitical strategy. They are fearful of China's growing regional dominance, and worried that the BRI is ultimately a means to supplant the prevailing US-led regional security structure and restore the Middle Kingdom order, with China as the only power that matters in the region. According to this view, once China has complete control of the regional logistics hubs and sea ports, this will severely limit the autonomy of China's neighbors, including South Korea, who will have to toe the Chinese line, both economically and politically, or risk their own peace and prosperity.