• 한국해양공학회지
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• 제35권3호
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• pp.238-246
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• 2021

The survivability of a naval ship is the ability of the ship and its onboard systems to remain functional and continue a designated mission in man-made hostile environments. A passive decoy system is primarily used as a weapon system for improving the survivability of a naval ship. In this study, an engagement scenario-based simulation program was developed for decoy effectiveness assessments against an anti-ship missile (ASM), which tracks a target with sea-skimming and active radar homing. The program can explain the characteristics of a target ship, such as the radar cross section and evasive maneuvers, as well as the operational performance of the onboard decoy system, the guidance method of the ASM, and the engagement environment's wind speed and direction. This paper describes the theory and formulations, configuration, and user interface of the developed program. Numerical examples of a decoy effect assessment of a virtual naval ship against an ASM are presented.

• Journal of Ship and Ocean Technology
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• 제10권2호
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• pp.24-36
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• 2006

Ship hullform is usually designed with a curve network, and smooth hullform surfaces are supposed to be generated by filling in (or interpolating) the curve network with appropriate surface patches. Tensor-product surfaces such as B-spline and $B\'{e}zier$ patches are typical representations to this interpolating problem. However, they have difficulties in representing the surfaces of irregular topological type which are frequently appeared in the fore- and after-body of ship hullform curve network. In this paper, we proposed a method that can automatically generate discrete $G^1$ continuous B-spline surfaces interpolating given curve network of ship hullform. This method consists of three steps. In the first step, given curve network is reorganized to be of two types: boundary curves and reference curves of surface patches. Especially, the boundary curves are specified for their surface patches to be rectangular or triangular topological type that can be represented with tensor-product (or degenerate) B-spline surface patches. In the second step, surface fitting points and cross boundary derivatives are estimated by constructing virtual iso-parametric curves at discrete parameters. In the last step, discrete $G^1$ continuous B-spline surfaces are generated by surface fitting algorithm. Finally, several examples of resulting smooth hullform surfaces generated from the curve network data of actual ship hullform are included to demonstrate the quality of the proposed method.

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2015년도 추계학술대회
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• pp.175-178
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• 2015

본 논문은 국내외 해양사고 원인의 60-80%에 해당하는 인적과실을 예방하기 위하여 긴급상황에 대한 가상현실 선원 훈련 플랫폼을 제안한다. 제안된 훈련 플랫폼은 가상현실 기술을 통해 긴급 상황 내 절차 숙달을 위한 상호작용 방법과 가상 선박 환경 내에서 군중 에이전트를 제어하는 군중 제어 방법을 제공한다. 제안된 훈련 플랫폼의 상호작용 방법은 훈련 몰입도를 높이기 위하여 음성인식과 행동인식을 사용한다. 군중 제어는 사회적 특성을 반영한 에이전트의 행동모델을 적용하여 자연스러운 시뮬레이션을 제공한다. 제안된 훈련 플랫폼의 효율성을 실험하기 위해 선박 내 화재 상황에 대한 가상 훈련 시나리오를 standalone 훈련 플랫폼으로써 구현하였다.

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2001년도 Proceeding of KIN-CIN Joint Symposium 2001 on Satellite Navigation/AIS, lntelligence , Computer Based Marine Simulation System and VDR
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• pp.121-140
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• 2001

- We explored the application of VR technologies to implement VR-Based Navigation Simulator Using VRML. - VR Ship Simulator gave some useful functions such as maneuvering ship with ease of learning the International Conventions to Preventing Collisions at sea. - AtoN Simulator can give attractive and interesting experiences with ease of learning the rules of IALA system and ease of comprehension of Aids to Navigation characteristics in various weather conditions - Results from tests, it became apparent that the developed VR-based Navigation Simulator could be adequate to next generation ship simulator.

• 한국항해항만학회지
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• 제40권4호
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• pp.189-196
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• 2016

본 논문은 선박 화재 상황에 대한 비상 대처 훈련을 가상 환경에서 수행하는 가상 선원 훈련 플랫폼을 제안한다. 제안하는 플랫폼은 HMD 기반의 몰입형 가상 환경을 제공하여 훈련 효과를 높일 뿐 아니라 네트워크를 통하여 다중 피훈련자가 함께 훈련에 참여하기 때문에 가상 환경에서의 협동 훈련을 수행할 수 있다. 본 플랫폼은 FDS 및 CFAST 기반의 오프라인 화재 시뮬레이션 결과를 기반으로 사실적인 화재 확산 및 시각화를 제공한다. 선박 화재 상황에 대한 해양 안전 교육 기관의 교재 시나리오를 기반으로 구현한 본 훈련 플랫폼은 기존의 절차 숙달 훈련에 더불어 몰입형 가상 기술을 이용한 장비 숙달 및 환경 숙달 훈련을 제공한다. 구현된 가상 선원 훈련 플랫폼은 장비 작동, 환경 통제, 원격 현장감을 기반하여 선원의 훈련도를 향상시키고 다수의 피훈련자가 실시간으로 임무를 공동 수행하는 가상 협력 훈련이 가능함을 보였다. 또한 구현된 플랫폼은 화재 진압 요령, 승객 유도 방법 등 다양하고 세부적인 기능 숙달 훈련이 가능함을 보였다.

• 한국CDE학회논문집
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• 제2권4호
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• pp.267-275
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• 1997

A ship-block cutting module is being developed as part of a computational system for a ship design. The module supports product-information to other modules in design process and displays ship-blocks in cutting-operation. Welding-information is essential to process-planning and scheduling. In the module, ship-blocks are modeled by Plate-Objects and then divided into several cutting pieces. The module automatically creates Welding-Objects containing welding-information in the process. Since the module is connected to WWW(World Wide Web), users in various platforms can access the models simultaneously In addition, users can check manufacturing constraints by inspecting a virtual model.

• 한국항해학회지
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• 제22권3호
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• pp.27-34
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• 1998

The paper is the second part on the 3-D sound-field creation implementing the Virtual Reality Ship Handling Simyulator(VRSHS). As mentioned in the previous part Ⅰ, the spatial impression, which arose from reproduced 3-D sound-field , give natural sound environmental context to a listener. This spatial impression is due to the reverberation by reflections and ,is can be obtain by using Head-Related Transfer Function(HRTF). In this work, we foumulate early and late reverberation models of the HRTF's with theoretical control factors based on the sound-energy distribution in an irregularly shaped enclosures. Using the reverberation models, we report results from psychophysical tests used to asses the validity of the proposed 3-D soud-field control method.

• International Journal of Naval Architecture and Ocean Engineering
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• 제7권5호
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• pp.848-872
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• 2015

Hydrodynamic derivatives or coefficients are required to predict the maneuvering characteristics of a marine vehicle. These derivatives are obtained numerically for a DTMB 5512 model ship by virtual simulating of captive model tests in a CFD environment. The computed coefficients are applied to predict the turning circle and zig-zag maneuvers of the model ship. The comparison of the simulated results with the available experimental data shows a very good agreement among them. The simulations show that the CFD is precise and affordable tool at the preliminary design stage to obtain maneuverability performance of a marine vehicles.

• 해양환경안전학회지
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• 제3권S1호
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• pp.3-3
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• 1997

• 한국해양공학회:학술대회논문집
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• 한국해양공학회 2004년도 학술대회지
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• pp.101-105
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• 2004

In this paper, theoretical basis of stereoscopic display is investigated and programmed to shaw the application which could be used in the Virtual Reality (VR), especially for ship design. Stereoscopic is based on the seperated view point of left and right eyes on the screen and making 3 dimensional image. There different stereoscopic methods such are red-blue, interlacing, side-by-side and above-below are imvestigated and implemente to shaw the simple ship model and inside of ship. To shaw the 3 dimensional view, OpenGL is used to make program by implementing the logic of stereoscopic. Simple models and ship design are implemented to survey the applicability of stereoscopic for ship design. The best way is to use two projectors to emit interlaced shape. It is expected to imply this technique in the VR application for ship design.