• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1991년도 한국자동제어학술회의논문집(국내학술편); KOEX, Seoul; 22-24 Oct. 1991
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• pp.704-706
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• 1991

In CAD/CAM system, many efforts are made to automate the converting process from drawling information to manufacturing Information. The most difficult step In this procedure is utilizing 2 dimensional drawing information In order to formulate 3 dimensional w&ling information. This paper emphasizes to mWe automatically series of convertirg steps which provide 3 dimensional wire frame, surface and solid modeling using feature recognition rules. With the standardization of design process and the recognition rule as preceding steps, it shows a good application tool to interface the design and manufacturing procedures in PC-Level CAD/CAM system.

• 대한조선학회논문집
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• 제45권4호
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• pp.432-440
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• 2008

Korean shipbuilders are starting to use three dimensional solid CAD systems to enhance their competitiveness in design and production. Despite many merits, three dimensional CAD systems reveal some problems in pipe-line modeling. Pipe-line modeling is heavily dependent on point data in routing. However, since the models built by sweeping or skinning operations do not have data about points and lines on the surfaces, the point data for routing are currently manually calculated by considering the diameters of the pipes and alignment conditions with other pipes. This process is inefficient and prone to errors. In order to enhance the pipe modeling, this paper presents an Offset Routing Program for a three dimensional CAD system, which aids designers to easily define the start points and to generate the pipe routings using reference objects.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2004년도 춘계학술대회
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• pp.870-874
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• 2004

This paper presents a three dimensional modeling and simulations of operation and running of a wheel loader using the ADAMS program. A wheel loader consists of a bucket, a boom, a crank, a front frame, a rear frame, a bucket cylinder, two boom cylinders, two steering cylinders, nine spherical joints, six universal joints, five translation joints, three inline joints, a revolute and a fixed joint. Judging from the actual degrees of freedom of the wheel loader, proper kinematic joints are selected to exclude redundant constraints in the modeling. Through the running simulation over a bump with the three dimensional modeling, the joint reaction forces are calculated.

• Applied Biological Chemistry
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• 제41권8호
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• pp.563-567
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• 1998

Computer aided molecular modeling can help to predict the three dimensional structure of the polypeptide without the sample. The study on soybean Bowman-Birk protease inhibitor (SBI) is valuable, because it has been recently known that SBI possesses anticarcinogenic activities and immune-stimulating properties. SBI has several isoinhibitors, whose isolation and characterization were reported in 1990. Among these, DII inhibits trypsin only. The different inhibitory specificities cannot be explained only by their different primary sequences, but is possible with further assistance by the study on their different three dimensional structures. The study on the three dimensional structure of DII using homology method is reported in this paper.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2005년도 추계종합학술대회
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• pp.683-686
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• 2005

By now, we have been analysing the resistance values on 3 dimensional structure using experimental statical method or theoretical modeling, while devices miniaturizing reveals the limitation of the traditional methods to calculate 3 dimensional resistance. In addition, 2 dimensional analysing can not produce 3 dimensional characteristic following miniaturizing. To solve the limitations , we must do high level modeling of semi-conductor process. In this thesis, we analyzed the Laplace equation that is the basic and important for 3 dimensional structure resistance with computer simulation method and on the basis of this, analyzed the characteristic of resistance of 3 dimensional structure communication semiconductor device.

• 한국추진공학회지
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• 제19권6호
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• pp.1-9
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• 2015

본 연구에서는 전열포의 플라즈마 발생장치에서 외부회로로부터 가해지는 펄스형 전기에너지에 의한 플라즈마 발생현상을 대상으로 영차원적 모델링 및 전산해석을 수행하였다. 전극 사이의 보어 내 플라즈마의 균일 온도 가정을 채용하여 질량 및 에너지 방정식을 간소화하였으며, 보어 및 전극 표면 상의 용발 모델 및 플라즈마 물성치 계산모델과 연계하였다. 해석결과는 1차원적 해석모델과 비교하여 상당히 일치함을 보여 영차원적 해석결과의 유효성을 확인할 수 있다.

• 한국자동차공학회논문집
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• 제18권3호
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• pp.116-126
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• 2010

The Korean rolling stock safety regulation stipulates that the collision deceleration of a car body should be maintained under average 5g and maximum 7.5g during train collisions. One-dimensional dynamic model of a full rake train, which is made up of nonlinear springs/bars-dampers-masses, is often used to estimate the collision decelerations of car bodies in a basic design stage. By the way, the previous studies have often used some average force-deformation curve for energy absorbing structures in rolling stock. Through this study, we intended to analyse how much the collision deceleration levels are influenced by the initial peak force modeling in the one-dimensional force-deformation curve. The numerical results of the one-dimensional dynamic model for the Korean High-Speed Train show that the initial peak force modeling gives significant effect on the collision deceleration levels. Therefore the peak force modeling of the force-deformation curve should be considered in one-dimensional dynamic model of a full rake train to evaluate the article 16 of the domestic rolling stock safety regulations.

• 한국공작기계학회논문집
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• 제10권3호
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• pp.31-37
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• 2001

In this paper, we developed an automated program for the modeling and simulation of three-dimensional roller gear cam mechanisms. The three-dimensional modeling for a roller-gear cam employs coordinate transformations based on the con-tact condition. the wire frame modeling followed by the shading technique using triangular meshing elements incorporat-ed the to reduce the number of data and computational load. Computer simulations for two kinds of products for rollger-gear cam mechansim illustrate the relative motion between the modeled roller-gear cam and a turret and thus show the effectiveness of the proposed modeling.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2008년도 추계학술대회A
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• pp.1057-1062
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• 2008

Representing a complex, three-dimensional shape, such as an automobile, requires a large amount of CAD data consisting of millions of approximated discontinuous points, which makes it difficult or even impossible to efficiently optimize the entire shape. For this reason, in this paper, function based design method is proposed to optimize the external shape of an automobile. A vehicle modeling function was defined in the form of a Bernstein polynomial to smoothly express the complex 2D and 3D automobile configurations. The sub-sectional parts of the vehicle modeling function are defined as section functions through classifying each subsection of a box model. It is shown that the use of the vehicle modeling functions has the useful advantages in an aerodynamic shape optimization.

• 한국해양환경ㆍ에너지학회지
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• 제14권2호
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• pp.121-129
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• 2011

EFDC 모형에서 해수유동과 퇴적물 이동을 모의하고자 하는 경우에 필요한 해수유동과 퇴적물 이동 모듈외의 수질 모델 등의 요소가 해수유동 모의시간에 미치는 영향을 검토하였다. 해수유동과 퇴적물 이동의 계산에 불필요한 수질요소관련 프로그램과 조건문 들을 모델에서 제거하는 방법으로 모형을 간략화하고 계산시간을 비교하였다. 수정된 EFDC 모형(EFDC-E)을 사용하여 목포해역에서 조류에 대하여 모의하고, 계산에 소요되는 시간과 모의결과를 EFDC 모형을 이용한 모의결과와 비교하였다. 또한, 2차원 모형과 3차원 모형을 동시에 적용하여 2차원 모의결과와 3차원 모의결과의 차이점에 대한 분석과 각 모형의 목포해역 조류 비대칭에 대한 재현성에 대해서 검토하였다. 간략화과정을 통해서 개선된 EFDC-E 모형은 EFDC 모형보다 2차원과 3차원 조류모의에서 약 3배 빠르게 계산하는 것을 확인할 수 있었다. 2차원 모의결과는 수심평균유속을 계산하여 상층에서 관측한 조류를 정확하게 재현하지 못하였으나, 3차원 모형을 적용한 결과는 2차원 모의보다 유속크기가 관측치와 보다 잘 일치하는 모습을 보였다.