• Korean Architects
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• no.3 s.180
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• pp.54-61
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• 1984

• Korean Journal of Computational Design and Engineering
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• v.9 no.2
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• pp.93-101
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• 2004

In mechanical design, optimization procedures have mostly been implemented solely by CAE codes combined by optimization routine, in which the model is built, analyzed and optimized. In the complex geometries, however, CAD is indispensable tool for the efficient and accurate modeling. This paper presents a method to carry out optimization, in which CAD and CAE are used for modeling and analysis respectively and integrated in an optimization routine. Application Programming Interface (API) function is exploited to automate CAD modeling, which enables direct access to CAD. The advantage of this method is that the user can create very complex object in Parametric and automated way, which is impossible in CAE codes. Unigraphics and ANSYS are adopted as CAD and CAE tools. In ANSYS, automated analysis is done using codes made by a script language, APDL(ANSYS Parametric Design Language). Optimization is conducted by VisualDOC and IDESIGN respectively. As an illustrative example, a mold design problem is studied, which is to minimize temperature deviation over a diagonal line of the surface of the mold in contact with hot glass.

• Journal of the Society of Naval Architects of Korea
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• v.43 no.3 s.147
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• pp.362-374
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• 2006

Currently, all design information of a hull structure is being first defined on 2D drawings not 3D CAD model at the initial ship design stage and then transferred to following design stages through the 2D drawings. This is caused by the past design practice, limitation on time, and lack of hull structural CAD systems supporting the initial design stage. As a result, the following design tasks such as the process planning and scheduling are being manually performed using the 2D drawings. For solving this problem, a data structure supporting the initial design stage is proposed and a prototype system is developed based on the data structure. The applicability of the system is demonstrated by applying it to various examples. The results show that the system can be effectively used for generating the 3D CAD model of the hull structure at the initial design stage.

• Transactions of the Korean Society of Mechanical Engineers
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• v.15 no.6
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• pp.1933-1947
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• 1991

The synthesis of supplementary features of injection molded parts has been done empirically, since it requires profound knowledge about the features' moldability and causal effects on the properties of the part, which are not available to designers through current CAD systems. RIBBER is a knowledge module which contains knowledge to permit non-experts as well as mold design experts to generate acceptable supplementary features of injection molded parts. A knowledge-based CAD system is constructed by adding the knowledge module, RIBBER, for mold feature synthesis and appropriate CAE programs for mold design analysis to an existing geometric modeler in order to provide designers, at the initial design stage, with comprehensive process knowledge-based CAD system is a new tool which enables the concurrent design and CIM with integrated and balanced design decisions at the initial design stage of injection molding.

• The Journal of Natural Sciences
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• v.8 no.1
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• pp.115-121
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• 1995

The Conventional database management system is not applicable because of their inadequate performance and difficulty of CAD database that is dependant to hierarchical structure and to repeat accesses of large data. For effective management and easy tool integration of CAD database, hierarchy Interface System(HIS) is designed and GROCO(Graph Representation fOr Complex Objects) Model is presented. Hierarchy Interface System which is composed of two subsystems of a configurator and a converter is designed for the interface between a conventional database management system and CAD tools. GROCO Model is a directed cyclic graph having five node-types for representing semantics and supports efficiently CAD database characters having a hierarchical structure of complex objects.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2002.11b
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• pp.523-528
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• 2002

Topology optimization is widely accepted as a conceptual design tool for the product design. Since the resulted layout of the topology optimization is a kind of digital images represented by the density distribution, the seamless process is required to transform digital images to the CAD model for the practical use. In this paper, the general process to construct a CAD model is developed to apply for topology images based on elements. The node density and the morphology technique is adopted to extract boundary contour of the shape and remove the noise of images through erosion and dilation operation. The proposed method automatically generates point data sets of the geometric model. The process is integrated with Pro/Engineer, so that the engineer in practice can directly handle with curves or surface form digital images.

• Journal of the KSME
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• v.32 no.2
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• pp.114-123
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• 1992

80년대부터 국내에 도입된 CAD/CAM시스템은 금형 및 관련 제조업체, 자동차 제조업체, 플랜트 /조선업체 등에서도 제도, 설계 및 설계해석용, CAM을 이용한 NC 가공용 등으로 적용되고 있다. 그러나 CAD/CAM 시스템을 판매업체의 불충분한 교육과 아프터 서비스가 아직 미흡하여, 시 스템 사용업체의 경우 시스템 활용기술 부족, 기술인력 부족 등의 이유로 활용도가 높지 못하다. 그럼에도 불구하고 많은 업체들이 CAD/CAM 도입을 본격적으로 준비하고 있으며, 93년의 경우 90년에 비해 사용자수가 2배가 되리라는 전망이다. 많은 업체의 경우 인원절감, 시간단축, 경비 절감 등의 비용효과와 정밀도/정확도 효과 등의 업무수준 향상 효과를 기대하며 추진하고 있으나 표준화, 관리의 체계화 효과 및 기업이미지 개선, 직원의식 수준 향상 등의 상징적 효과도 크다고 볼 수 있다. 국내에 CAD/CAM 시스템 보급을 촉진하기 위해서는 소프트웨어의 한글화 작업이 이루어져야 하고 분야별로 다양한 데이터베이스가 구축되어야 할 것이며, 가격이 저렴하고 속 도가 빠른 형상 모델링 기술발전이 요구된다. 끝으로, 우리 실정에 맞는 CAD/CAM 소프트웨어의 국산화 작업이 우리가 풀어야 하는 최대 과제라 할 수 있다.

• Journal of the Society of Naval Architects of Korea
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• v.34 no.4
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• pp.119-126
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• 1997

In this parer, a protocol system is developed, which automates the sequential procedure that transforms the information of compartment generated by SIKOB, the calculation program of ship design, to the STEP format which is used as the input data of next level of ship design. The schemata representing hull form and compartment are constructed. The STEP physical files are made by instancing these schemata using the results of SIKOB. They are transmitted to the CAD system and then worked on the CAD system. It means that they could be used as the data of next level of ship design.

• CDE review
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• v.2 no.1
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• pp.1-6
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• 1996

CG 등의 컴퓨터 지원에 의한 도형처리 시스템 중에서 특히 설계제도를 지원하는 시스템으로서 CAD가 제공되고 있다. CAD에는 대형 컴퓨터를 플랫폼으로 하는 메인프레임(집중형) CAD와 EWS(엔지니어링 워크 스테이션)을 플랫폼으로 하는 EWS/CAD 및 퍼스널 컴퓨터를 베이스로 한 퍼스널 CAD가 있는데 최근에 컴퓨터의 고성능화와 소형화의 흐름에 따라 퍼스널 CAD가 CAD의 주류로 되고 있다. 그 큰 요인으로서 퍼스널 CAD는 하드웨어 및 소프트웨어를 포함한 시스템 가격이 EWS/CAD 등을 비롯한 다른 CAD에 비하여 저렴한 가격대라는 것과 조작성이 우수하다는 점을 들 수 있다. 또한 최근에는 OS(Operating System: 컴퓨터를 움직이기 위한 기본적 소프트웨어)의 주류가 싱글 유저.싱글 태스크인 MS-DOS(이하 DOS라 한다)에서 싱글 유저.의사 멀티 태스크인 MS-Windows(이하 Windows라 한다)에로 이행하고 있으며 퍼스널 CAD도 그에 대응하는 것으로 되고 있다. 여기서는 이 Windows에 대응하는 퍼스널 CAD의 최신의 기술동향 및 OS에 대하여 설명한다.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.30 no.5 s.248
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• pp.488-495
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• 2006

The demand for the use of 3D CAD data over the Internet environment has been increased. However, transmission of 3D CAD data has delayed the communication effectiveness because of the CAD data size. Lightweight CAD file design methodology is required for rapid transmission in the distributed environment. In this paper, to derive lightweight CAD files from commercial CAD systems, a file translation system producing a native file is constructed first by using the InterOp and API of the ACIS kernel. Using the B-rep model and mesh data extracted from the native file, the lightweight CAD file with topological information is constructed as a binary file. Since the lightweight CAD file retains topological information, it is applied to the dimensional verification, digital mock-ups and visualization of CAD files. Effectiveness of the proposed lightweight CAD file is confirmed through various case studies.