• Bulletin of the Society of Naval Architects of Korea
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• v.26 no.2
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• pp.32-40
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• 1989

Dynamic ship positioning(DP) system is used to keep the position and heading of a ship, or a floating platform, above a pre-selected site on the seabed by using thrusters. This paper presents a control system based on filtering technique and optimal control theory. The planar motions of a vessel are assumed to consist of low frequency(LF) component and high frequency(HF) one. The former is mainly due to thrusters, current, wind and second order wave forces, while the latter is mainly due to first order oscillatory component of the wave force. Furthermore position measurement signals include the noise. By means of self-tuning filter and Kalman filter techniques, LF motion estimates and HF ones are seperately achieved from the position measurements of the vessel. The estimated LF motions are used as input to the feedback loops. The total thruster power is minimized using the Linear Quadratic Gaussian control theory. The performance of the vessel with the DP system is investigated by computer simulation.

• The Journal of the Acoustical Society of Korea
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• v.15 no.4
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• pp.43-49
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• 1996

This research proposes a system for speaker independent Korean continuous speech recognition with 247 DDD area names using keyword spotting technique. The applied recognition algorithm is the Dynamic Programming Neural Network(DPNN) based on the integration of DP and multi-layer perceptron as model that solves time axis distortion and spectral pattern variation in the speech. To improve performance, we classify word model into keyword model and non-keyword model. We make an experiment on postprocessing procedure for the evaluation of system performance. Experiment results are as follows. The recognition rate of the isolated word is 93.45% in speaker dependent case. The recognition rate of the isolated word is 84.05% in speaker independent case. The recognition rate of simple dialogic sentence in keyword spotting experiment is 77.34% as speaker dependent, and 70.63% as speaker independent.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.17 no.2
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• pp.160-167
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• 2018

The purpose of this study is to develop a process for forming a MPa ultra-high strength steel sheet to reduce weight and improve product strength. To do this, we performed the initial process design based on empirical formulas in a handbook and experience of skilled engineers, and researched the effects of major process variables on spring back by analyzing the forming analysis and experimental results. This paper suggests an optimal process design of the seat rail lower parts, using a MPa ultra-high strength steel sheet. This satisfies the dimensional accuracy and strength requirements for the product.

• Proceedings of the Korean Society for Emotion and Sensibility Conference
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• 2000.04a
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• pp.126-132
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• 2000

This paper presents a facial expression recognition based on Gabor wavelets that uses a fuzzy C-means(FCM) clustering algorithm and neural network. Features of facial expressions are extracted to two steps. In the first step, Gabor wavelet representation can provide edges extraction of major face components using the average value of the image's 2-D Gabor wavelet coefficient histogram. In the next step, we extract sparse features of facial expressions from the extracted edge information using FCM clustering algorithm. The result of facial expression recognition is compared with dimensional values of internal stated derived from semantic ratings of words related to emotion. The dimensional model can recognize not only six facial expressions related to Ekman's basic emotions, but also expressions of various internal states.

• Proceedings of the IEEK Conference
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• 2002.06c
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• pp.13-16
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• 2002

This paper proposes a method to track hand gesture and to recognize the gesture pattern using Kalman filter and continuous dynamic programming (CDP). The positions of hands are predicted by Kalman filter, and corresponding pixels to the hands are extracted by skin color filter. The center of gravity of the hands is the same as the input pattern vector. The input gesture is then recognized by matching with the reference gesture patterns using CDP. From experimental results to recognize circle shape gesture and intention gestures such as “Come on” and “Bye-bye”, we show the proposed method is feasible to the hand gesture-based human -computer interaction.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2011.06a
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• pp.71-73
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• 2011

다기능 선박조종시뮬레이터(Full-mission Shiphandling Simulator)는 항해사, 선장 및 도선사의 자질 향상을 위한 교육뿐만 아니라 항만개발을 위한 사전 검토와 해난사고 발생 시, 원인규명을 위한 분석에도 이용되고 있다. 한국해양수산연수원에서는 이러한 목적을 위하여 2011년 2월 28일 Russia Transas 제품의 선박조종시뮬레이터를 설치 완료 하였다. 이 FMSS는 적어도 360도의 수평시각을 가진 대형 구형화면에 여섯(6) 자유도 운동을 하는 본선 및 타선을 실시간으로 표현하는 photo-realistic high resolution computer graphic visual system과 같은 최신기술을 사용하는 가장 현대화된 최고급 해상용 시뮬레이터로 해난 사고 윈인규명을 위한 분석 연구 목적을 위하여 광범위한 출처로부터 모델시험과 자료의 신뢰할만한 공식적 기록들에 근거한 매우 정확한 수력학적 선박 모델링 소프트웨어로 이루어졌다. 여기서는 이 FMSS의 형태와 복잡성을 상세하게 소개한다.

• Proceedings of the CALSEC Conference
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• 1999.11a
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• pp.373-384
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• 1999

전자상거래가 활성화되면서 네트워크를 이용한 상품의 구매가 증가 하고 있다. 현재 전자 상거래에 이용되는 대부분의 상품은 유형의 상품이 주를 이루고 있다. 디지털 상품(DP: digital product)은 물류비용이 없고 수익성이 높은 장점을 가지고 있지만 불법 복제 문제 때문에 현재 전자상거래에서는 기피하는 상품으로 취급받고 있다. 디지털 상품의 불법 복제 문제는 사용권 관리 기술의 부재가 가장 큰 이유이다. 현재 제공되는 전자상거래 서비스는 사용권 부여 대상의 식별 방법이 없고, 대상의 이동 방지가 불가능하고, 해킹 방지가 미비하며, 기타 전자상거래 구조가 미완성되어 사용권 관리상에 많은 문제점을 들어내고 있다. 본 논문은 새로운 사용권 관리 기술인 동적 사용권 관리(DLC: Dynamic License Control) 기술을 이용하여 디지털 상품의 불법 복제를 막을 수 있는 디지털 상품의 유통 정보 관리 기술에 대하여 논한다.

• Journal of Advanced Marine Engineering and Technology
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• v.29 no.2
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• pp.236-242
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• 2005

Dynamic Positioning(DP) system maintains ship's position (fixed location or predetermined track) exclusively by means of CPPs and thrusters. To generate the control input adequate to various situation an integrated controller for CPPs and thrusters is required. The integrated controller is composed of a thrust calculation algorithm and a thrust allocation algorithm. The thrust calculation algorithm generates thrusts in the surge direction and the sway direction from the desired forward and lateral speed and generates a moment about the yaw axis from desired heading angle. The thrust allocation algorithm allocates the generated thrusts and moment to each CPP and thruster. Computer simulations are executed to confirm the effectiveness of the suggested controller.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.12 no.11
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• pp.4726-4731
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• 2011

This paper proposed the algorithm to select optimal grinding condition for plunge grinding in the batch production unit. In order to apply to the proposed algorithm, the state variable for plunge grinding process was defined and the optimal grinding condition for each cycle in batch production was decided by genetic algorithm. Based on the optimized grinding condition in each cycle, the optimal grinding condition for whole batch production was selected by dynamic programming. The proposed algorithm was evaluated by computer simulation.

• Proceedings of the Korea Information Processing Society Conference
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• 2007.05a
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• pp.1393-1395
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• 2007

IEEE LOM 기반의 ADL SCORM, KEM 등을 통해 생산된 학습 콘텐츠는 데이터의 표준을 준수하여 이종의 학습시스템에서도 연동 될 수 있도록 상호운용성이 크게 향상되었고, 이를 통해 학습 콘텐츠의 유통과 검색, 접근이 매우 수월하게 개선되었다. OAI-PMH는 XML 기반의 학술 정보에 대한 메타데이터 통합을 통하여 개방형 검색이 가능하도록 시스템을 구현하기 위한 프레임워크로써 학술 정보의 통합 유통 체제에 매우 활용도가 높다. 본 논문에서는 OAI-PMH 의 SP/DP 개념의 메타데이타 수확(Harvesting) 기술을 활용하여 국내의 교육기관(학교), 연구 기관, 학술단체, 기업연수원 등에서 보유하고 있는 SCORM, KEM 기반의 학습 콘텐츠와 DC(Dublin Core) 기반의 학술 정보를 통합하여 사용자에게 정보 서비스를 제공하기 위한 개방형 학습.학술 정보 공유 시스템 설계를 제안하고자 한다.