• Journal of Korean Society for Geospatial Information Science
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• v.6 no.1 s.11
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• pp.65-74
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• 1998

The acquisition and analysis system of accurate geometrical digital data is very important in side of maintaining the traditional culture for the preservation of cultural properties. This study is on the construction and shape analysis of precise digital data to manage more successfuly using the CRP method and 3D Mono Mobile System. Also this study could acquisite 3D geometrical digital data, make such various space analysis and section, projection, and calculation of bias, area and volume and modeling by rendering technique on the misterious bell of great king of SungDuck, one of the greatest bells in periods of TongIl Silla. So, We suggest utilization of image analysis method to safety diagnosis for the maintenance of cultural properties, archeological and artistic research.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.17 no.1
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• pp.248-254
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• 2013

In location finding system using spaced multi-sensor, there is the phenomenon that the position estimation accuracy is degraded by the location of signal sources and the sensors. This phenomenon is called GDOP(Geometric Dilution Of Precision) effect. and to minimize these effects, research is needed on how. In this paper, I will describe how to minimize GDOP effect, estimating possibility of GDOP using AOA(angle of arrival) information of spaced multi sensors, and removing sensor error factor in position estimation.

• Journal of the Korean Society for Precision Engineering
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• v.30 no.10
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• pp.1087-1093
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• 2013

In this study, a measurement method of double ball-bar is proposed to measure the geometric errors of an ultra-precision roll mold machine tool. A volumetric error model of the machine tool is established to investigate the effects of the geometric errors to a radius error and a cylindricity of the roll mold. A measurement path is suggested for the geometric errors, and a ball-bar equation is derived to represent the relation between the geometric errors and a measured data of the double ball-bar. Set-up errors, which are inevitable at the double ball-bar installation, also are analyzed and are removed mathematically for the measurement accuracy. In addition, standard uncertainty of the measured geometric errors is analyzed to determine the experimental condition. Finally, the proposed method is tested and verified through simulation.

• Journal of Navigation and Port Research
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• v.29 no.3 s.99
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• pp.269-274
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• 2005

Geodetic surveying using precise GPS equipment are used without analysis with a statistical verification of GPS observed value and it was preformed by necessity to integration projection of digital topographic map and nautical Chart for integration geographic information system construction. The purpose of this study proposes method that improve accuracy of GPS observed value and direction that integrally manage digital topographic map and electronic nautical chart in analyzing the boundary line error between digital topographic map and nautical Chart. For improvement of the precision of GPS observed value, the author studied precision-analysis of GPS observed value by geometric strength and variance factor in 3 control points used in GPS network adjustment. And like this, produce EDM measurement using this GPS observation results and compare the whole boundary point error when set digital topographic map and nautical chart by these boundary.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1993.10a
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• pp.456-460
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• 1993

최근 제품의 설계와 제조의 동기화를 위해 제품설계 및 공정설계 분양에서 동시공학(concurrent engineering)의 개념을 도입한 부품의 특징형상(feature)에 의한 접근방법이 중요한 과제로 대두되고 있다. 특징형상은 CAD/CAM 통합을 위한 정보전달의 매개체로서 CAPP 시스템 개발시의 CAD/CAPP 인터페이스에 중요한 기능을 가진다. 제조분야에서의 특징형상 적용은 특징형상인식(feature recognition)과 특징형상에 의한 설계 (feature based design)의 두 가지 분야가 있으며, 이 두 분야 모두 특징형상의 상세한 정의와 분류를 필요로 한다. 본 연구에서는 특징형상의 기하학적인 정의 및 분류를 위한 체계를 제시하고, 사출금형의 구성부품을 대상으로 특징형상의 기하학적 속성으로부터 특징형상의 분류기법을 개발한다.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1995.10a
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• pp.1133-1137
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• 1995

This paper presents a numerical method of the global search for an optimal geometric path for a manipulator arm amid obstacles. Finite term quintic B-splines are used to describe an arbitrary point-to-point manipulator motion with fixed moving time. The coefficients of the splines span a linear vector space, a point in which uniquely represents the manipulator motion. All feasible geometric paths are searched by adjusting the seed points of the obstacle models in the penetration growth distances. In the numerical implementation using nonlinear programming, the globally optimal geometric path is obtained for a spatial 3-link(3-revolute joints) manipulator amid several hexahedral obstacles without simplifying any dynamic or geometric models.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1995.10a
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• pp.830-835
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• 1995

To quickly determine the effect of the substitute component on the machine's performance is very important in the defign and the manufacturing processes. And minimizing machine cost and maximizing machine quality mandata predictability of machine accuracy. In the study, in order to evaluate the effects of the component's geometric errors and dimensions on the machining accuracy of gantry-type 5-axis machining centers, a geometric error analysis and virtual manufacturing system is developed based on the mathematical model for the shape generation motion of machine tool considering the component's geometric errors and dimensions, the solid modeling techniques and so on.

• Journal of Korean Society for Geospatial Information Science
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• v.5 no.2 s.10
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• pp.55-63
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• 1997

Precision digital data capture and spatial analysis system to cultural properties play important roles in preserving the existing properties. This study presents the acquisition oi digital data in geometrical context and spatial analysis for more effective management to cultural properties. Established in the same coordinates system, Precision 3D measurements and image analysis were peformed. In addition, geometrical analysis, and 3D monitoring to Songsanri Royals Tombs in Gongju were carried out in generating basedata for conservation plan.

• Journal of the Korean Society for Precision Engineering
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• v.15 no.6
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• pp.58-63
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• 1998

There are lots of factors that are related to the geometric characteristics of machined surface. Among them, the tool path and milling mode (up cut milling or down cut milling) are the easiest controllable machining conditions. Thus, the first objective of this research is to study the effects of them on the milled surface that is generated by an end milling tool. To get precision parts, not only the machining process but also the measurement of geometric tolerance is important. But, this measurement requires a lot of time, because the infinite surface points must be measured in the ideal case. So, the second objective is to propose a simple flatness measurement method that can be available instead of the 3-D geometric tolerance measurement method, using a scale factor and characterized points. Finally, it is also shown that the possibility of flatness improvement by shifting the consecutive fine cutting tool path as compared with the last rough cutting tool path.

• Journal of the Korean Society for Precision Engineering
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• v.15 no.10
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• pp.172-179
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• 1998

To quickly determine the effect of the substitute component on the machine's performance is very important in the design and manufacturing processes. And minimizing machine cost and maximizing machine quality mandate predictability of machine accuracy. In this study, in order to evaluate the effects of the component's geometric errors and dimensions on the machining accuracy of gantry-type 5-axis machining centers, a geometric error analysis and virtual manufacturing system are developed based on the mathematical model for the shape generation motion of machine tool considering the component's geometric errors and dimensions, the solid modeling techniques and so on.