• Korean Journal of Computational Design and Engineering
• /
• v.6 no.3
• /
• pp.147-156
• /
• 2001

In the construction industry, construction process includes a variety of design stages with cooperation and regulation by many related disciplines. In addition, the construction market is growing and becoming more complex. With this characteristic, design information has become more and more complicated and difficult to manage by the simple and traditional data management methodology. In the practical field, although CAD has been widely available for the last ten years, related disciplines have not shared digital information efficiently. This paper suggests a construction CAD data exchange model that has been developed through investigation and analysis of Korean construction CAD practices and foreign CAD standards. Moreover, this paper investigates a CAD data exchange model using STEP to improve information availability and overcome the limit of CAD systems.

• Korean Journal of Computational Design and Engineering
• /
• v.14 no.3
• /
• pp.159-167
• /
• 2009

For the robust exchange of parametric CAD model data, it is very important to perform mapping rightly and accurately between different CAD models. However, data model mapping is usually performed on a case-by-case basis. This results in the problem that mapping quality fluctuates very widely depending on the abilities of developers. In order to solve this problem, the concept of symantic distance is adapted and applied to the translation of parametric CAD model data in order to measure the difference between different CAD models quantitatively in a computer-interpretable form and systematize the mapping process.

• Journal of KIISE:Software and Applications
• /
• v.27 no.1
• /
• pp.33-40
• /
• 2000

Computer Aided Process Planning (CAPP) plays a key role by linking CAD and CAM. Given CAD data of a part, CAPP has to recognize manufacturing features of the part. Despite the long history of research on feature recognition, its research results have rarely been transferred into industry. One of the reasons lies in the separation of feature recognition and process planning. This paper proposes to integrate the two activities through AI techniques, and presents efforts for manufacturable feature recognition, setup minimization, feature dependency construction, and generation of an optimal machining sequence.

• Korean Journal of Computational Design and Engineering
• /
• v.7 no.3
• /
• pp.157-169
• /
• 2002

In the initial stages of ship design, designers represent geometry, arrangement, and dimension of hull structures with 2D geometric primitives such as points, lines, arcs, and drawing symbols. However, these design information(‘2D geometric primitives’) defined in the drawing sheet require more intelligent translation processes by the designers in the next design stages. Thus, the loss of design semantics could be occurred and following design processes could be delayed. In the initial design stages, it is not easy to adopt commercial 3D CAD systems, which have been developed f3r being used in detail and production design stages, because the 3D CAD systems require detailed input for geometry definition. In this study, a semantic product model data structure was proposed, and an initial structural CAD system was developed based on the proposed data structure. Contents(‘product model data and design knowledges’) of the proposed data structure are filled with minimal input of the designers, and then 3D solid model and production material information can be automatically generated as occasion demands. Finally, the applicability of the proposed semantic product model data structure and the developed initial structural CAD system was verified through application to deadweight 300,000ton VLCC(Very Large Crude oil Carrier) product modeling procedure.

• Journal of the Korean Society for Precision Engineering
• /
• v.16 no.9
• /
• pp.25-34
• /
• 1999

In spite of the advance of 3D solid modeling technology, there are some distinct areas where 2D CAD S/W are still dominant, and more competent comparing with 3D CAD S/W. For example, in the manufacturing of 2D-shaped electrical parts, most related manufacturing tools have 2D geometric features by nature, and 3D solid models applied to these parts have substantial overheads. Nevertheless, most 2D CAD S/W have no topological inquiry services because they have no such information on their geometrical database inherently. Thus, it is needed to extract such information from 2D CAD database for developing more advanced application such as automated drafting/design S/W. In this paper, the extraction of topological information from 2D CAD has been performed in general way using concept of B-rep. A general extraction algorithm, data structure and meta file format for 2D topological object have been developed and successfully applied to the development of the automated lead frame die design system in Samsung Aerospace. it is also possible to provide a flexible, powerful topology-oriented functionality on any common 2D CAD S/W.

• The Journal of Korean Academy of Prosthodontics
• /
• v.55 no.2
• /
• pp.218-224
• /
• 2017

The implant-supported fixed dental prosthesis in irradiated maxilla needs meticulous treatment planning due to low bone healing capacity. All-on-4 concept implantation can reduce the number of implants to be placed avoiding bone grafting procedure. Conventionally, prefabricated angled abutments for tilted implants have been used. However, in this case, it was replaced with computer-aided design and computer-aided manufacturing (CAD/CAM) abutment. This case report described all-on-4 concept implantation and fabrication of CAD/CAM zirconia fixed dental prostheses using CAD/CAM titanium abutments.

• Journal of the Korean Society for Precision Engineering
• /
• v.31 no.7
• /
• pp.597-604
• /
• 2014

High efficiency production requires the improved performance of CAD/CAM system. Although the CAD and CAM have been significantly developed over the last three decades, they must still study on the reuse of information during process. In this study, we developed a new integrated CAD/CAM system which can reuse the information generated in previous processes, in order to improve its performance. In addition, the developed system was verified by comparing with working-time, and system reproducibility was also examined with tolerance in the unmanned operation. Experimental results showed 58% reduction in working-time of 2D Auto-CAM module, 80% in case of 3D Auto-Exchange module, and 54.5% in case of Auto-Design module.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.2 no.2
• /
• pp.101-106
• /
• 2001

The integrated design system for injection molding has been studied. The current CAD system do not provide mold designers with necessary function for CAD/CAPP/CAE interface except the geometric modeling capability. This paper describes a feature-based CAD system for mold and moldbase design which enables the concurrent design and CIM, with integrated design procedure, at the initial design stage of injection molding A new design methodology and resulting feature data files for this design system are also discussed.

• Journal of the Korean Society of Clothing and Textiles
• /
• v.29 no.1 s.139
• /
• pp.46-57
• /
• 2005

This empirical research aims to identify and compare key success factors in Computer Aided Design (CAD) education in Korea, Japan, Germany and USA. Employing a couple of statistical methods (multiple regression and factor analysis) on survey data, it was found that the decisive factors in the CAD education differed among four countries. Generally speaking, however, educational methods are less important than educational conditions, of which professors and educational environment are dominant factors. This implies that the so called constructivistic way of teaching/learning is not so effective as expected. In order to improve educational performance in Korea, as far as CAD education is concerned, professors need to enhance relationship with industry and universities to support more hardware and software.

• Journal of the Korean Society for Precision Engineering
• /
• v.17 no.9
• /
• pp.53-61
• /
• 2000

The manufacture of a marine propeller typically requires long lead time to generate 5-axis tool path. Hence it may take several weeks to manufacture a satisfactory propeller with a general purpose CAD/CAM system. In this research a dedicated 5-axis CAD/CAM system for machining marine propellers has been developed, The system employs various methods to enhance the productivity : interference-free tool path generation employing check vectors and optimum cutter size determinants. In addition an iterative NURBS modeling technique is used to improve the accuracy of the modeled surface and effective cutting conditions are determined and recommended empirically to increase the productivity. The proposed CAD/CAM system has been implemented with C++ and OpenGL graphic library on the Windows system. The system validation and sample results are also given and discussed.