• 대한조선학회논문집
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• 제52권5호
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• pp.407-417
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• 2015

For the more accurate prediction on manoeuvring performance of a ship at initial design phase, bare hull manoeuvring coefficients were estimated by RANS(Reynolds Averaged Navier-Stokes) based virtual captive model tests. Hydrodynamic forces and moment acting on the hull during static drift and harmonic oscillatory motions were computed with a commercial RANS code STAR-CCM+. Automatic and consistent mesh generation could be implemented by using macro functions of the code and user dependency could be greatly reduced. Computed forces and moments on KCS and KVLCC 1&2 were compared with the corresponding measurements from PMM(Planar Motion Mechanism) tests. Quite good agreement can be observed between the CFD and EFD results. Manoeuvring coefficients and IMO standard manoeuvres estimated from the computed data also showed reasonable agreement with those from the experimental data. Based on these results, we could confirm that the developed virtual captive manoeuvring model test process could be applied to evaluate manoeuvrability of a ship at the initial hull design phase.

• 한국CDE학회논문집
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• 제3권1호
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• pp.40-47
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• 1998

Recently, the various driving simulator have been used widely to analyze the handling performance of vehicle and to verify the motion control algorithm of vehicle. In this study, a virtual driving simulator based on the 20-DOF vehicle model is realized to estimate the handling performance and stability of a 4WS (Four-wheel-steering) and/or 4n(Four-wheel-driving) vehicle. Especially the DC motor controlled 4WS actuator is modelled in order to reflect the effect of the responsiveness of actuator on the handling performance and stability. And the realized simulator can be applied to develope a real time simulation system for designing and testing the real vehicles.

• International Journal of CAD/CAM
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• 제8권1호
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• pp.41-44
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• 2009

This paper describes an implementation of virtual teeth modeling for a haptic dental simulation. The system allows dental students to practice dental procedures with realistic tactual feelings. The system requires fast and stable haptic rendering and volume modeling techniques working on the virtual tooth. In our implementation, a volumetric implicit surface is used for intuitive shape modification without topological constraints and haptic rendering. The volumetric implicit surface is generated from input geometric model by using a closest point transformation algorithm. And for visual rendering, we apply an adaptive polygonization method to convert volumetric teeth model to geometric model. We improve our previous system using new octree design to save memory requirement while increase the performance and visual quality.

• 한국의상디자인학회지
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• 제22권1호
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• pp.1-13
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• 2020

The purpose of this study is to create a 3D avatar from 3D human body shape data using the CLO 3D virtual clothing program and to verify the feasibility of avatar production using the virtual clothing system for verifying size and shape. The research method was to select one virtual representative model that is the closest to the mean size of each body item for each age group. Using the 3D human body scan shape of a 40-69 years old male was applied to the CLO 3D virtual wearing system. Using the CLO 3D Avatar conversion menu, we verified the feasibility of creating a 3D avatar that reproduces the human body scan shape. In the dimension comparison between the 3D avatar and the fictitious representative model, the dimension difference was noticeable in height, circumference, and length. However, as a result, the converted 3D avatar showed less than a 5% difference in most human dimensions. In addition, since the body shape and posture were reproduced similarly, the utilization of the avatar was verified.

• 디지털콘텐츠학회 논문지
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• 제12권2호
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• pp.185-194
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• 2011

본 논문은 게임과 가상현실 시스템을 위한 스테이트챠트(Statecharts) 기반의 점진적인(progressive) 행위 LOD 모델을 소개하고 있다. 시스템의 리소스를 최대한 활용할 수 있도록 상황에 따라 임의의 복잡도를 가진 행위 LOD를 자유롭게 생성할 수 있는 스테이트챠트 기반의 명세 프로세스를 포함하여, 모델간 개량(refinement) 연산, 모델 간 전환(switching) 법칙, LOD 선택 정책 등을 정의하였다. 더불어, 제안된 접근방법의 가능성을 보여주기 위해, 가상 자동차가 단계적으로 설계되어가면서 점진적인 LOD 모델이 되는 예를 들고 있다.

• 한국생산제조학회지
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• 제21권3호
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• pp.368-375
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• 2012

Durability performance evaluation of automotive components is very important and time consuming task. In this paper, to reduce vehicle component development time and cost virtual testing simulation technology is used to evaluate durability performance of a passenger car front aluminum sub-frame. Multibody dynamics based vehicle model and virtual test simulation model of a half car road simulator are validated by comparisons between rig test results and simulation results. Durability life prediction of the sub-frame is carried out using the model with road load data of proving ground which can evaluate accelerated durability life. We found that the durability performance of the sub-frame is sufficient and it can be predicted within short time compared to rig test time.

• 한국주거학회:학술대회논문집
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• 한국주거학회 2006년도 추계학술발표대회 논문집
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• pp.196-201
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• 2006

Existing model houses have played an important role in allow the customers to choose apartment. As the information technology has been advanced (e.g. a high-speed internet available in unit), customers' personality and preference to the design of apartment and the purchasing pattern have been changed. Construction firms have introduced VR(Virtual Reality) model house (e.g. Quick Time Virtual Reality) to meet the customers' expectation and need. The reality-based QTVR model house does not provide enough quality to satisfy the customers' expectation. To complement the shortcoming of the QTVR model house, this study presents a web-based cyber model house developed by using Turntool and Javascript. The cyber model house allows to communicate between supplier and customer over the internet.

• 패션비즈니스
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• 제23권5호
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• pp.96-110
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• 2019

With the continuous development of artificial intelligence using computers in the Fourth Industrial Age, the virtual space created by virtual reality experiences boosted by the power of artificial intelligence, provides a new experience for us. The purpose of this study is to explore the new aesthetics that the fashion industry provides to users in virtual space created by virtual reality technology. This research method is based on theoretical research on virtual reality technology and virtual space and constructs a research model applied to this research. The scope of this study is the application of virtual reality technology to fashion shows, fashion exhibitions, and fashion design apps on the website of professional virtual reality technology and fashion for the last five years from 2014 to 2019, which actively merged virtual reality technology with modern fashion. We will analyze the cases one by one. The results of this study are as follows. First, this study shows that the constructed virtual space of modern fashion using virtual reality technology creates three kinds of physical space, perceptual space, and imaginary space based on the commutative theory of virtual space formed by Swedish scholar J. $Widestr{\ddot{o}}m$. Second, virtual reality technology applied to fashion shows, fashion exhibitions, and fashion design apps is characterized by four aesthetic characteristics of presence, perceptual expansion, interactivity, and immersion in physical space, perception space, and imagination space.

• 한국실내디자인학회논문집
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• 제14권3호
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• pp.216-223
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• 2005

In this study, we would like to suggest a virtual model house where the users participate in the planning of the apartment directly in order to supply the apartment which is suitable for the fast change of the resident's characterization, multiplication, and preference in this like high-speed information society. The users have various preferences and demands in the high level information society. It is necessary for the architect to communicate with the users in order to suggest the various styles of habitats that one can treat various life style and life cycle which reflects the demand. In addition, the object of this paper is the construction and using of the participating virtual model house that the resident can plan the preferred space design of the main house before moving Into the apartment and change space design of the main house after moving into the apartment following the variety of life style and the changing of life cycle. Regarding the effect of this study, firstly, it is possible to supply the plate type following the user's preference in order to enhance the quality of uniformed type apartment. Secondly, it is possible to maintain and control the high quality building using sharing the building information with planning, construction, maintain, interior, and related company by constructing the database. Thirdly, the unified database which is constructed by XML can supply the effective environment of apartment information exchange between other companies.

• 한국CDE학회논문집
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• 제22권1호
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• pp.89-99
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• 2017

In order to make a virtual endoscopy system effective for exploring the interior of the 3D model of a human organ, it is necessary to generate an accurate navigation path located inside the 3D model and to obtain consistent camera position and pose estimation along the path. In this paper, we propose an approach to virtual navigation of blood vessels, which makes proper use of orthogonal contours and skeleton curves. The approach generates the orthogonal contours and the skeleton curves from the 3D mesh model and its voxel model, all of which represent the blood vessels. For a navigation zone specified by two nodes on the skeleton curves, it computes the shortest path between the two nodes, estimates the positions and poses of a virtual camera at the nodes in the navigation zone, and interpolates the positions and poses to make the camera move smoothly along the path. In addition to keyboard and mouse input, intuitive hand gestures determined by the Leap Motion SDK are used as user interface for virtual navigation of the blood vessels. The proposed approach provides easy and accurate means for the user to examine the interior of 3D blood vessels without any collisions between the camera and their surface. With a simple user study, we present illustrative examples of applying the approach to 3D mesh models of various blood vessels in order to show its quality and usefulness.