• 대한기계학회논문집A
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• 제20권5호
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• pp.1486-1497
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• 1996

The problem of determining the 3-demensional motion of any two rough bodies after a collision involves some rather long analysis and yet in some points it differs essentially from the corresponding problem in tdwo dimensions. We consider a special problem where two rough ellipsolids moving in any manner collide, and analyze the three dimensional impact process with Coulomb friction and Poisson's hypothesis. The differential equations that describe that process of the impact induce a flow in the tangent velocity space, the flow patterns characterize the possible impact cases. By using the graphic method in impulse space and numerical integration thchnique, we analyzed the impact process inall the possible cases and presented the algorithm for determining the post-impact motion. The principles could be applied to the general problem in three dimensions. We verified the effectiveness of the analysis results by simulating the numerous significant examples.

• 한국전산유체공학회:학술대회논문집
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• 한국전산유체공학회 1996년도 춘계 학술대회논문집
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• pp.85-92
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• 1996

Numerical simulations are made for the three-dimensional flow around a wing in ground effect craft haying the complex geometry. A numerical tool is developed for the primary design of hull and wing shape of practical Wing-In-Ground effect(WIG) stop. The finite-difference method is utilized to descretize the governing equations and pressure field is obtained by using Marker-And-Cell(MAC) method. The air and water flows are simultaneously simulated in the time-marching solution procedure for the Navier-Stokes equation. The porosity technique and the density function are devised for the implementation of the three-dimensional body-boundary and the free-surface conditions, respectively. In this paper, a craft is modeled simply by three blocks containing a wing mounted on a main body horizontally, with the endplate. The numerical calculations of a WIG advancing in a calm water are performed and the WIG-generated wave profiles are also obtained. In the final paper, details of the numerical methods employed for the present study and calculated results are discussed.

• 대한기관식도과학회지
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• 제16권2호
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• pp.138-144
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• 2010

Background: Tracheal deviations are encountered frequently in head and neck tumors especially in thyroid cancer. Dyspnea and stridor are symptom calling for surgery. The method of evaluation in tracheal deviation is not well established yet. This paper is aimed to suggest objective tools to evaluate tracheal deviation in relation to cervical vertebra. Material and Method: Ten cases of thyroid cancers were recruited retrospectively. Tracheal inner shadow and shape of cervical vertebra were reconstructed three dimensionally using 3D-doctor to compare position of trachea in relation to vertebral body. Extent of deviation was scored in relation to both lateral borders of vertebral body. Angles between trachea and spinous process were measured in axial CT and compared between study group and control group. Results: Deviation scores were statistically significant between study group (mean=1.1) and control group (mean=0) (p=0.0008). Deviation angles at maximal tumor size in study group (mean=160.3 Degrees) and deviation angles of control group (mean=177.1 Degrees) were statistically significant (p=0.0007). Angles at maximal deviation of three dimensional images ages in study group (mean=162.6 Degrees) and deviation angles of control group (mean=177.1 Degrees) were statistically significant (p=0.0089). Conclusion: Tracheal deviation can be evaluated using scoring of three dimensional images and measuring angle between trachea and vertebral spine.

• 복식
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• 제57권10호
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• pp.50-59
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• 2007

This study has been conducted to classify elderly men's feet with the three-dimensional body scanner data of Size Korea. It was intended to assist the manufacturing of the shoes that can appropriately perform the functions of feet, by providing the specific information about the shapes of elderly men's feet that are altered as a result of aging and shoe-wearing for a long time. The findings are as follows. 1. The investigations into the average and standard deviation of the measurements and index values for the elderly men's feet showed a large personal difference in the items of length and circumference. 2. The factors constituting the elderly men's feet were observed to be the size of foot width(Factor 1), the central angle of feet and the extension of toes(Factor 2), the size of ankle(Factor 3), the positions of lateral malleolus and pternion(Factor 4), and the position and size of medial malleolus(Factor 5). 3. The cluster analysis for the classification of elderly men's feet produced three types of them.

• 한국의류학회지
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• 제30권11호
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• pp.1598-1607
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• 2006

The purpose of this study was to analyze the proportion of gathered skirts using a three-dimensional measurement system. And in this experiment, we have attempted to accumulate three-dimensional data of wearing model and find out adequate methods for analyzing shape of clothes. The experimental design consists of two factorial designs. We established three different kinds of fabrics, ratio of gathers. The measurement tool for three-dimensional model was whole body 3D scanner(Exima-WBS2H). Analysis program used in experiment is RapidForm 2004 PP1 and Pattern Design 2000. Data analysis utilizes SPSS WIN 10.0 Package. As the results show, there were different effect of gather and proportion of shapes among the measurements of width, thickness and areas made by different lines of vision in cross-sectional silhouette. And there were difference shapes of section area at each part of gathered skirts between vertical-outline silhouette and vortical-plane silhouette made by gathering conditions. And also the cross-sectional silhouettes and vertical silhouettes were related to shape of clothes.

• 전기학회논문지
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• 제63권1호
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• pp.162-172
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• 2014

A three-dimensional dynamic model for simulating various motions of full vehicle is presented. The model has 16 independent degrees of freedom (DOF) consisting of three kinds of components; a vehicle body of 6 DOF, 4 independent suspensions equipped at every corner of the body, and 4 tire models linked with each suspension. The dynamic equations are represented in six coordinate frames such as world fixed coordinate, vehicle fixed coordinate, and four wheel fixed coordinate frames. Then these lead to the approximated prediction model of vehicle posture. Both lateral and longitudinal dynamics can be computed simultaneously under the conditions of which various inputs including steering command, driving torque, gravity, rolling resistance of tire, aerodynamic resistance, etc. are considered. It is shown through simulations that the proposed 3D model can be useful for precise design and performance analysis of any full vehicle control systems.

• 한국전자현미경학회:학술대회논문집
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• 한국현미경학회 2004년도 제35차 추계학술대회 및 제2회 HVEM 이용자 워크샵
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• pp.47-52
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• 2004

• 한국섬유공학회:학술대회논문집
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• 한국섬유공학회 2001년도 학술발표회 논문집(Proceedings of the Korean Textile Conference) 상
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• pp.247-250
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• 2001

• 복식문화연구
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• 제14권1호
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• pp.40-47
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• 2006

Three-dimensional body scanners were used for years in the clothing manufacturing fields. The 3D body surface provide essential data to draft patterns for mass customization, virtual fit model, and computerized patternmaking systems. This research proposed the methods of drafting patterns for men's jacket by using three dimensional body scan data. Eight male subjects were scanned, the surface data was flattened. The differentials of the flattened body surface and the jacket draft were measured, and analyzed the regressions. To verify the fit of the patterns, the jacket was constructed by the regression formulae and tested by experts. The fit of the jacket were significantly improved rather than a ready-made suit especially the shoulder areas. This means that the methods that we proposed were good to improve the fit of the garments and could be used effectively to implement mass customization strategies in the apparel retail industry.

• 한국의상디자인학회지
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• 제11권2호
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• pp.11-21
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• 2009

Recently, as custom-made demand about female underwear is increased, securing of a various dimension system is urgent, and satisfaction of each customer cannot be heightened with established dimensions. If we could measure shape of a living body with a fast and simple method, the custom-made demand of customers could be satisfied in the underwear as well as a clothing industry by using the method. One of the alternatives is shape measurement of the living body by a Moire fringe method. If we put a grating in front of an object to be measured and illuminate light, a Moire fringe with contour line shape is generated in the object, so we can conveniently measure object shape without touching directly by using the pattern. The Moire fringe and three-dimensional shape of the breast of the living body was acquired by a PMP method using a polygon mirror, and height and bottom width of the breast of the living body were measured by using obtained data in this study. Data of breast shape measurement through a mannequin was collected in a previous step as basic material for measuring the breast shape measurement of the living body. Three women in the twenties were selected as one of methods for measuring breast shape of a woman. As a result of the breast shape measurement of a living body A, it was measured that height of the breast was about 67.24mm and the bottom width was $13781.60mm^2$. This study is expected to contribute for collecting basic data of a female underwear industry and establishing a specification of a dimension system.