• 한국공작기계학회논문집
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• 제16권2호
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• pp.78-83
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• 2007

In this paper, the digital model of the micro-factory has been established, inspected and evaluated by progress of assembly, manipulation and examination. The new paradigm of the system analysis is realized by digital simulation of the factory. The digital manufacturing system of the micro-factory was simulated through UML(Unified Modeling Language) with the object-oriented logical model analysis method and then the micro lens module assembly system was simulated with MST(Micro System Technology) Application Module.

• 한국CDE학회논문집
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• 제7권3호
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• pp.170-176
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• 2002

To exchange CAD data between heterogeneous CAD systems, we generally use a neutral format especially STEP, which is the international standard (ISO-10303) for product model data exchange. AP214 (Application Protocol) for the automotive industry not only takes into account geometry and organizational data, but also provides a classification mechanism for product modeling. When reading a STEP file during a design process that is exported from other CAD systems, it is a burden to a designer to go through the tedious process of removing duplicate or non-manifold entities, adjusting parts, and rearranging text. We analyze the structure of AP214 and develop a healing tool to solve the following problem. Without the assembly information in the Master workspace of CATIA, or to read a STEP file from Pro/Engineer, a designer should do a repetitive process of disintegrating an assembly into parts one by one. We have developed a post-processing tool for STEP AP214 that separates out a part from an assembly model and adjusts superfluous or useless entities using the ACIS kernel.

• 화약ㆍ발파
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• 제23권1호
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• pp.47-54
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• 2005

본 연구에서는 $PFC^{3D}$를 사용하여 시멘트 모르타르와 굵은 골재로 이루어진 콘크리트 기둥의 발파과정에서 나타나는 폭발과 파괴현상을 모사하여 보았다. 폭원모델링 과정에서는 공내입자들의 반경을 팽창/수축시키는 기법을 통해 공벽입자들에 접촉력의 형태로 폭발압력을 부여하는 방법을 사용하였다. 현장 발파실험에서는 철근콘크리트 기둥을 대상으로 초안폭약을 사용하여 발파하고 그 파괴거동을 고속카메라를 이용하여 관찰하였다. 모사과정에서는 철근의 규격과 입자요소의 크기에 따른 해석시간을 고려하여 모르타르와 굵은 골재로 이루어진 콘크리트 기둥을 대상으로 제안된 폭원모델링 기법을 적용하여 해석을 실시하였다. 해석결과 나타난 저항선의 이동속도는 $17\~24\;m/s$로서 실험치 $14\~18\; m/s$를 약간 상회하고 있으나 제안된 폭원모델링 기법을 사용한다면 암석이나 기타 재료들에 대한 발파과정에서 나타는 파괴거동을 수치적으로 보다 유사하게 모사할 수 있을 것으로 판단된다.

• 한국산업정보학회:학술대회논문집
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• 한국산업정보학회 1999년도 추계공동학술대회 논문집:21세기지식경영과 정보기술
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• pp.759-768
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• 1999

In this paper, we developed a simulation model of a car parts assembly line to improve the system performance such as worker's utilization balancing, productivity. This simulation model has been developed using QUEST, a true 3D discrete event simulation pakcage that is designed for modeling and analysis of manufacturing systems. We have suggested the results obtained to improve the system performances of an existing production line.

• 산업경영시스템학회지
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• 제25권1호
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• pp.14-19
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• 2002

This paper describes an automatic parts design system for gears, brake, and clutch. These parts are important components of the power transmission assembly. In conventional design process, the design of power transmission requires a number of recurrent calculations and drawings. In this paper, we propose a three-dimensional automatic design system that reduces the number of recurrent calculations and drawings. The system consists of three modules for designing gear, brake, and clutch. The proposed system has been applied to develop a transmission of forklift truck and shown to be a useful system.

• 한국경영과학회:학술대회논문집
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• 한국경영과학회/대한산업공학회 2003년도 춘계공동학술대회
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• pp.821-826
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• 2003

The Purpose of this paper is to automate the representation of manufacturing line using Petri net model. In the manufacturing cell, the line can be represented using workflow which is composed of Bill of Material (BOM) and Bill of Processes (BOP). BOP shows the precedence of processes and the relationship between assembly and disassembly. As a modeling scheme, generalized stochastic Petri net is adopted. For a problem domain with flexible manufacturing cell, Petri net model is made and behavioral properties are analyzed.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 1997년도 춘계학술대회 논문집
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• pp.179-185
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• 1997

This paper presents machine vision technique with a camera modeling that accounts for major sources of camera distortion, namely,radial, decentering, and thin prism distortion. Radial distortion causes an inward or outward displacement of a given image point from its ideal location. Actual optical systems are subject to varios degrees of decentering,that is,the optical centers of lens elements are not strictly collinear. Thin prism distortion arises form imperfection in lens design and manufacturing as well as camera assembly. It is our purpose to develop the vision system for the pattern recognition and the automatic test of and to apply the line of part manufacturing.

• 대한지리학회지
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• 제48권3호
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• pp.387-401
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• 2013

우리나라 선거구 획정은 인구의 증감이나 행정구역의 변경뿐만 아니라 지극히 정치적인 의도와 목적을 가지고 이루어져 선거결과에 중대한 영향을 미친다. 이 논문은 선거구 구획의 실행 측면에 초점을 맞추어 선거구 구획을 위한 대안적 방법을 제시하는 데 초점을 맞추고 있다. 즉 과정에서 자의성이 개입될 수 있는 부분에 절차적이고 객관적인 선거구 획정 방법론을 제시하고자 한다. 이를 위하여 선거구 획정기준(인구등가성, 연속성, 공간적 조밀성)을 준수하는 공간 최적화 모델을 고안하고 제19대 선거구 획정결과에서 논란이 되었던 용인시에 적용하여 그 가능성을 평가한다. 모델의 분석 결과는 정치적 고려나 임의적 개입 없이 기저의 데이터만으로 기준을 만족하는 선거구를 확정할 수 있음을 보여주었다. 특히, 모델에 의해서 도출된 선거구는 기존 선거구에 비하여 인구등가성을 향상시켰다.

• 한국BIM학회 논문집
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• 제8권1호
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• pp.15-23
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• 2018

Geometry control of precast members is the most important technology for modular construction. In this paper, image-based modeling and rendering (IBMR) technology was adopted for 3D modeling of precast elements. It is necessary to use match-casting method for precast post-tensioned column assembly. Preassembly using 3D models created by image processing can minimize construction error. Augmented reality devices are used to check the geometry of the segment. Laboratory-scale tests were performed. The proposed process has been applied to the real precast bridge pier segments.

• Korea-Australia Rheology Journal
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• 제20권3호
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• pp.153-164
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• 2008

Modeling and experiments of three electrospinning systems have been presented and they are i) axisymmetric instabilities in electrospinning of various polymeric solutions, ii) non-isothermal modeling of polymer melt electrospinning, and iii) control of nanoparticle distribution and location via confined self-assembly of block copolymers during electrospinning. It has been demonstrated that predicted simulations are in good agreement with corresponding electro spinning experiments, and theoretical analysis provides fundamental understanding of phenomena that take place during electrospinning of various polymeric liquids.