• Transactions of the Korean Society of Mechanical Engineers
• /
• v.16 no.4
• /
• pp.658-666
• /
• 1992

In developing computer-aided design technology for optimization of stamping die design, it has been an important issue to treat the frictional constraint acting on the blank holder surface. The main goal of this work is to establish database of draw bead restraint force and clarify friction characteristic for various automotive sheet steels, which is essential in developing friction algorithm that can be used for CAD of stamping die design. Draw bead friction tester is used to evaluate the various parameters that affect the draw restraint force and the coefficient of friction for the cold rolled and the coated sheet steels such as drawing rate, lubricant type, surface property of material, etc.

• Journal of the Society of Naval Architects of Korea
• /
• v.31 no.4
• /
• pp.15-22
• /
• 1994

The efforts to utilize modern computers for the hull form design of ships, started in the 1960s. In Korea, tools for the computer-aided hull form design such as FORAN system have been used from the 1970s. However, the development efforts for such tools have just started. To maximize the output from the limited research resources in this field, a reference model for the development is proposed. The model cail be used to decompose the task into sub-tasks, and to integrate the separately developed component technologies afterwards. To produce the reference model, the state-of-the-arts has been surveyed. including both foreign and domestic researches, within both shipbuilding industry and general CAD sectors. In the process, component functions for the hull form design have been identified. The reference model is constructed using these identified component functions.

• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.20 no.11
• /
• pp.3525-3537
• /
• 1996

This paper presents a CAD program develpoed on a microcomputer in order to support graphic and computational assessment of ergonomic problems associated with the design of a man-in-cab system. The program is coded to help workspace designers with ergonomic evaluations needed in the design stage. This paper proposed a biomechanical -ergonomic evaluations needed using man and workplace models. The human model is developed to have dimensions obtained from the Korean anthropometric data reported in 1992. Its graphical representation is based on a wire-frame model but, whenever necessary, body segments can be represented by a solid model with hidden line/faces removed and shaded. Workplace models are presented for cabs of the excavator, one of the most popular construction vehicles. A workplace model consists of an operator seat, a steering wheel. two control levers, two pedals, and a control panel. The workplace elements can be modified in their sizes, positions, and orientations by changing the reference point and design parameters. An algorithm for the view test is suggested and loaded to provide a visual evaluaiton of the overall layout of a workplace model.

• Transactions of the Korean Society of Automotive Engineers
• /
• v.13 no.2
• /
• pp.162-169
• /
• 2005

To achieve rapid new car developments and cost saving, new approaches for automotive general assembly in manufacturing preparations are needed. In this paper, CAD and DMU technologies for design and evaluation of machines and equipments are discussed. Digital Mock-up based on 3-D CAD models usually apply in the area of concept design and design review. We focus on manufacturing preparations of the machine and equipment. Detail procedures, examples and considerations of DMU are suggested in this paper. By applying DMU in the manufacturing preparations of general assembly, time, cost and quality of engineering can be enhanced through engineering collaboration.

• The Journal of Korean Academy of Prosthodontics
• /
• v.59 no.1
• /
• pp.79-87
• /
• 2021

The digital workflow of optical impressions by the intraoral scanner and CADCAM manufacture of dental prostheses is actively developing. The complex process of traditional impression taking, definite cast fabrication, wax pattern making, and casting has been shortened, and the number of patient's visits can also be reduced. Advances in intraoral scanner technology have increased the precision and accuracy of optical impression, and its indication is progressively widened toward the long span fixed dental prosthesis. This case report describes the long span implant case, and the operator fully utilized digital workflow such as computer-guided implant surgical template and CAD-CAM produced restoration after the digital impression. The provisional restoration and customized abutments were prepared with the optical impression taken on the same day of implant surgery. Moreover, the final prosthesis was fabricated with the digital scan while utilizing the same customized abutment from the provisional restoration. During the data acquisition step, stl data of customized abutments, previously scanned at the time of provisional restoration delivery, were imported and automatically aligned with digital impression data using an 'A.I. abutment matching algorithm' the intraoral scanner software. By using this algorithm, it was possible to obtain the subgingival margin without the gingival retraction or abutment removal. Using the digital intraoral scanner's advanced functions, the operator could shorten the total treatment time. So that both the patient and the clinician could experience convenient and effective treatment, and it was possible to manufacture a prosthesis with predictability.

• Proceedings of the Korean Institute Of Construction Engineering and Management
• /
• 2008.11a
• /
• pp.297-300
• /
• 2008

Since the Three Dimensional Computer Aided Design(3D CAD) appeared in 1990s, Building Information Modeling(BIM) has got the great issue in the construction project nowadays. BIM is the process of managing and generating building information during life cycle of a construction project. And information can be moved to 3D modeling flexibly in BIM. As a result, a field of estimating has also been doing researches in the calculation of the amount of building materials from 3D modeling. And the Construction Cost Estimating Software which is generally used over the world has been trying to be applied to the Construction project in Korea. But, when we consider the productivity, it is less efficient than the existing way in Korea which use the 2D Drawings when they take off the Quantity. Also, there are lots of difference how to estimate the construction cost. between Korea and the others. Because it is a bit hard to apply the software used in the other countries to the construction project in Korea, people couldn't use it well in the construction project actually. In this study, for developing the appropriate construction cost estimating software rooted in 3D in Korea, we suggest 3D CAD Add-on Program for a Quantity Take-off which can move quantitative information to 3D CAD.

• Journal of Institute of Convergence Technology
• /
• v.5 no.2
• /
• pp.33-36
• /
• 2015

In this paper, the development history of random packings for several generations was briefly introduced. We demonstrate the application of 3D printing to the fabrication of Pall rings, directly using computer aided design (CAD) models. The CAD was used to design Pall rings with different number of blades. The models were then printed by using UV curing of acrylonitrile-butadiene-styrene (ABS) resins. The results show that 3D printing is a promising method for producing precisely controlled packing materials. It is also expected that 3D printing is helpful for the fundamental studies of highly efficient packing materials with complex geometrical shapes.

• Proceedings of the Korean Operations and Management Science Society Conference
• /
• 1991.10a
• /
• pp.261-267
• /
• 1991

다품종소량생산의 특징을 갖고 있는 금형공업에서 컴퓨터통합생산시스템(Computer Integrated Manufacturing System;CIMS)의 실현을 위한 중요한 분야의 하나는 부품설계도면으로부터 최종제품을 생산하는데 필요한 공정계획의 자동화, 즉 컴퓨터를 이용하여 공정계획을 자동적으로 생성하는 자동공정계획시스템(Computer Aided Process Planning;CAPP) 기술의 개발이다. 국내외적으로 CAPP분야의 연구는 컴퓨터 지원에 의한 자동화 기술의 급속한 발전과 더불어 지난 20여년 동안에 기계가공품에 관한 CAPP은 약 150여가지가 개발되었으나, 이는 컴퓨터 지원에 의한 설계의 자동화(Computer Aided Design;CAD)나 컴퓨터 지원에 의한 제조의 자동화(Computer Aided Manufacturing;CAM)분야에 비해 상대적으로 저조한 형편이다. 특히 금형을 대상으로 한 CAPP시스템의 개발은 아직 초기단계에 있기 때문에, 본 연구에서는 사출금형을 대상으로 하여 실용성이 있는 공정설계시스템을 개발함을 목적으로 한다. 일반적으로 공정계획은 "소재로부터 제품을 경제적, 효율적으로 생산하는데 필요한 제조공정의 체계적인 결정"이라고 정의할 수 있다. 공정계획은 제품의 종류와 수량, 재료와 부품의 종류, 보유 생산설비와 제조기술의 수준에 따라 다르나, 공정설계(Process Design)와 작업설계(Operation Design)로 구분할 수 있다. 본 연구에서는 공정계획을 광의의 공정설계로 정의하고, 공정설계와 공정계획을 동의어로 통용토록 한다. 기존의 CAPP시스템의 개발에 관한 기본적인 접근방법은 변성형방법(Variant method), 창성형방법(Generative method) 및 자동화방법(Automatic method)이 있다. 이들 CAPP시스템을 개발할 때 사용하는 기법은 크게 5가지- (1) GT(group Technology) 접근기법, (2) Bottom-up 접근기법, (3) Top-down 접근기법, (4) AI와 전문가시스템(Expert System) 접근기법, (5) 컴퓨터 프로그래밍 언어 - 로 분류할 수 있다. 본 연구에서는 전문가시스템 기법을 도입해서 사출금형 공정계획전문가의 지식과 경험을 획득하여 지식베이스를 구축하고, 전문가시스템 셀(shell)중 CLIPS를 이용하여 자동공정계획시스템인 Mold CAPP을 개발하였다.PP을 개발하였다.

• Journal of the Korean Society of Costume
• /
• v.55 no.4 s.94
• /
• pp.95-106
• /
• 2005

The purpose of this study was to research the design methods to express jacquard design using CAD. For this study, two design patterns were divided; in addition, each design pattern is applied to two different weaving types, single woven fabric and double well cloths. As a result, 16 samples were produced by applying 4 design methods (warp shrunk as half size design/weft shrunk as half size design - A, warp shrunk as half size design/weft original size design - B, warp original size design/weft shrunk as half size design - C, warp original size design/weft original size design - D) to the two design patterns with the two weaving types. The result of this study can be summarized as follows. 1. The most delicate design method was Method D. However, Method B which took half the time less than Method D was almost as delicate as the Method D on the surface. 2. Method B was judged as a considerably efficient method for time and cost. 3. Method D was considered as most suitable for elaborate parts and delicate lines. However, it was considered uneconomical since it took the longest time. 4. Mettled A took 2.5 times less time than Method D. Therefore, Method A was more applicable to producing high density design. 5. Method C is not considered as a useful method as it showed rough surface and took long time by applying high design zoom except intentional design.

• Journal of the Institute of Convergence Signal Processing
• /
• v.2 no.4
• /
• pp.97-102
• /
• 2001

In computer-aided design, partitioning is task of clustering objects into groups to that a given objection function is optimized It is used at the layout level to fin strongly connected components that can be placed together in order to minimize the layout area and propagation delay. Partitioning can also be used to cluster variables and operation into groups for scheduling and unit selection in high-level synthesis. The most popular algorithms partitioning include the Kernighan-Lin algorithm Fiduccia-Mattheyses heuristic and simulated annealing In this paper we propose a genetic algorithm searching solution space for the circuit partitioning problem. and then compare it with simulated annealing by analyzing the results of implementation.