• The Journal of Korean Association of Computer Education
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• v.8 no.1
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• pp.73-80
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• 2005

To achieve a natural and plausible interaction with deformable objects and to setup the desirable initial conditions of simulation, user should be able to define and control the geometric constraints intuitively. In addition, user should be able to utilize the simulation as a problem solving platform by experimenting various simulation situations without major modification of the simulator. The proposed physically based geometric constraint simulation system solves the problem using a non-linear finite element method approach to represent deformable objects and constraint forces are generated by defining geometric constraints on the nodes of the object to maintain the restriction. It allows user to define and modify geometric constraints and an algorithm converts these geometric constraints into constraint forces which seamlessly integrate controllability to the simulation system. Simulator can handle linear, angular, inequality based geometric constraints on the objects. Our experimental results show that constraints are maintained in the tight error bound and preserve desired shape of deformable object during the entire simulation.

• 제어로봇시스템학회:학술대회논문집
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• 1991.10a
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• pp.376-382
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• 1991

In the analysis of constrained holonomic systems, the Lagange multiplier method yields a system of second-order ordinary differential equations of motion and algebraic constraint equations. Conventional holonomic or nonholonomic constraints are defined as geometric constraints in this paper. Previous works concentrate on the geometric constraints. However, if the total energy of a dynamic system can be computed from the initial energy plus the time integral of the energy input rate due to external or internal forces, then the total energy can be artificially treated as a constraint. The violation of the total energy constraint due to numerical errors can be used as information to control these errors. It is a necessary condition for accurate simulation that both geometric and energy constraints be satisfied. When geometric constraint control is combined with energy constraint control, numerical simulation of a constrained dynamic system becomes more accurate. A new convenient and effective method to implement energy constraint control in numerical simulation is developed based on the geometric interpretation of the relation between constraints in the phase space. Several combinations of energy constraint control with either Baumgarte's Constraint Violation Stabilization Method (CVSM) are also addressed.

• Journal of the Korean Society for Railway
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• v.6 no.1
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• pp.58-65
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• 2003

Wheel/Rail geometric constraint relationships, such as effective conicity and gravitational stiffness, strongly influence the lateral dynamics of railway vehicles. In general, these geometric contact characteristics are nonlinear functions of the wheelset lateral displacement. There is a need to develop a wheel/rail geometric contact simulation program for wheels and rails with arbitrary profiles for the prediction of the dynamic behavior of railway vehicles. An algorithm to simulate any combination of wheels and rails is employed and a GUI for easy analysis is constructed. The simulation program is applied to KTX which will run on both KTX and conventional rails, two rail standards having different rail profiles. The results show that the two rail systems have different geometric contact characteristic

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2004.10a
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• pp.1444-1447
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• 2004

For the OLED evaporation process, thin film thickness uniformity is of great practical importance. In order to achieve the better thickness uniformity, geometric simulation of film thickness distribution profile is required. In this paper, a geometric modeling algorithm is introduced for process simulation of full-color OLED evaporating system. The physical fact of the evaporation process is modeled mathematically. Based on the developed method, the uniformity of the organic layer thickness can be successfully controlled.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.9 no.2
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• pp.119-124
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• 2000

In this paper based on geometric optics and geometric modeling aspheric surface of the side mirror mold with dead angle reduced have been designed and machined in a CNC machining center, Surface roughness of the mold was evaluat-ed by usin the surface shaping system. Surface generating simulation of a ball endmill process is investigated. Through the simulation based on the surface-shaping system 3-D engineered surfaces and properties of engineered surfaces are obtained, Computer simulation provides the effective working conditions through the prediction of geometric properties of engineered surfaces. The rear view mirror and room mirror play important role on the safe driving condition as a observation of environment but the rear view mirror can not provide complete information of driving environments due to the existence of the dead angle. The analysis on the shape of formed mirror shows that the proposed me？ improves range of a driver's sight.

• Structural Engineering and Mechanics
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• v.35 no.2
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• pp.127-140
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• 2010

This paper focuses on a number of criteria that enable controlling the influence of geometric simplification on the quality of finite element (FE) computations. To perform the mechanical simulation of a component, the corresponding geometric model typically needs to be simplified in accordance with hypotheses adopted regarding the component's mechanical behaviour. The method presented herein serves to compute an a posteriori indicator for the purpose of estimating the significance of each feature removal. This method can be used as part of an adaptive process of geometric simplification. If a shape detail removed during the shape simplification process proves to be influential on mechanical behaviour, the particular detail can then be reinserted into the simplified model, thus making it possible to readapt the initial simulation model. The fields of application for such a method are: static problems involving linear elastic behaviour, and linear thermal problems with stationary conduction.

• Proceedings of the KSR Conference
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• 2003.05a
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• pp.645-650
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• 2003

Wheel/Rail geometric constraint relationships, such as effective conicity and gravitational stiffness, strongly influence the lateral dynamics of railway vehicles. In general, these geometric contact characteristics are nonlinear functions of the wheelset lateral displacement. There is a need to develop a wheel/rail contact simulation program for wheels and rails with arbitrary profiles for the prediction of the dynamic behavior of railway vehicles. An algorithm to simulate any combination of wheels and rails is employed and a GUI for easy analysis is constructed. The simulation program is applied to KTX which will run on both KTX and conventional rails, two rail standards having different rail profiles. The results show that the two rail systems have different geometric contact characteristic

• Journal of the Korean Society of Costume
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• v.60 no.6
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• pp.11-22
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• 2010

Purpose: The purpose of this study is to develop golf wear textile design, produce simulation and samples, and create original designs using geometric patterns. Significance: If modern people's trend to pursue well-being is be associated with healthy and active lifestyle and the design which combines a sport sense into artistic image appears in golf wear, it is a very significant effort to settle the role of sport as a mega trend. Contents: This study examined the general concept of geometric patterns and the situation and characteristics of women's golf wear. Finally, the design and simulation of gold wear textile were proposed. Study Instruments: For theoretical research, articles, books, literatures, and Internet materials published at home and abroad were reviewed and collected. For empirical research, a dot, a stripe(a line), a square, and an oval were selected and simulation was tested visually after the development of textile designs. Finally it was directly produced and golf wear design was developed. Photoshop CS 3 and Wacom intuos 3 were used as a general-purpose program and hardware respectively. DTP printing was used for sample work. Based on research results, geometric patterns range broadly and diversely from prehistoric remains and relics to contemporary art, design, architecture, and fashion. It is a unique formative element with value and attraction as the infinite object of inquiry beyond an area and the times. The combination of geometric patterns with art touch could complement the rigidity of design. It contributed to the perception of important role of art in the design area, namely, the importance of design containing artistry.

• Journal of the Korean Society of Costume
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• v.59 no.6
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• pp.72-81
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• 2009

The purpose of this study is to develop geometric patterns which can be reinterpreted in a modern sense and textile designs which can be commercialized in the mural painting of Goguryeo Dynasty's tomb. Of 42 tombs where genres and portraits could be observed, the costume style of Goguryeo dynasty could be mainly observed in the tombs built in the 4th and 5th centuries. Since geometric patterns found in the portrait could be represented in a modern sense, this study was intended to develop the patterns of a necktie which is one of cultural products by applying geometric patterns in the mural painting of Goguryeo Dynasty's tomb in the 5th century with many patterns distributed. The scope of patterns was limited to a square, a triangle, a circle, and a diagonal line which were the basic of geometric patterns found in the mural painting. The methods of study were literature review and empirical study. Adobe Photoshop CS3 was used to edit geometric patterns found in the mural painting of Goguryeo Dynasty's tomb in the 5th century. By extracting a square(${\square}$), a triangle(${\vartriangle}$), a circle(${\bigcirc}$), and a diagonal line(${\diagdown}$) from edited images, predicted images were proposed before products were made. Finally textile designs were made through the simulation of edited design patterns in the necktie and handkerchief. This study will contribute to the positive effects on the development of cultural product designs applying the characteristic of geometric patterns and the construction of Korean image.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2010.05a
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• pp.127-128
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• 2010