• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 한국공작기계학회 2005년도 춘계학술대회 논문집
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• pp.115-124
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• 2005

This paper analyzes the problems that occurred in the magnification process for a fine input image and investigates a method to improve the problems. This paper applies a curve interpolation algorithm in CAD/CAM for the same test images with the existing image algorithm in order to improve the problems. As a result. the nearest neighbor interpolation. which is the most frequently applied algorithm for the existing image interpolation algorithm. shows that the identification of a magnified image is not possible. Therefore. this study examines an interpolation of gray-level data by applying a low-pass spatial filter and verifies that a bilinear interpolation presents a lack of property that accentuates the boundary of the image where the image is largely changed. The periodic B-spline interpolation algorithm used for curve interpolation in CAD/CAM can remove the blurring but shows a problem of obscuration, and the Ferguson's curve interpolation algorithm shows a more sharpened image than that of the periodic B-spline algorithm. For the future study, hereafter. this study will develop an interpolation algorithm that has an excel lent improvement for the boundary of the image and continuous and flexible property by using the NURBS. Ferguson's complex surface. and Bezier surface used in CAD/CAM engineering based on. the results of this study.

• Journal of Industrial Technology
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• 제22권B호
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• pp.79-88
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• 2002

This paper deals with a case study on the process improvement and the layout design of a boiler factory with FactoryCAD. Firstly, two alternatives of job reallocation are suggested with the understanding of problems in current process. The layout planning for these new alternatives is carried out by simple procedure and the detailed analyses are performed by the aid of FactoryCAD program. The result shows that the new layout plan brings on about 10% reduction of travel distance. The utilization of FactoryCAD program can simplify the process of layout design.

• Transactions of the Korean Society of Mechanical Engineers A
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• 제31권6호
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• pp.635-643
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• 2007

As many engineers and technicians are involved in the design process of large scale and/or complex products, there are a lot of miss matches and interferences due to designers' faults and several kinds of CAD systems. Recently, CAD systems are applied to verify and check the assembly process. Digital Mock-Up(DMU) system, a tool to build a virtual mock-up in the design stage, has been used to prevent the interferences and miss matches during precision design processes. Using the virtual assembly tool, engineers are able to design precision and interference free parts without physical mock-ups. Instead of a single CAD source, several CAD systems are used to design a complex product. Several organizations are involved in the distributed design environment for heterogeneous multi-CAD assembly. XML and the lightweight CAD file are proposed for the multi-CAD assembly. XML data contains hierarchy of the heterogenenous multi-CAD assembly. STEP PDM schema and STEP ISO 10303-28 formations are applied to construct the XML data. The lightweight CAD file produced from various CAD files through ACIS kernel and InterOp not only contains mesn, B-Rep and topological data, but also is used to visualize CAD data and to verify dimensions. Developed system is executed on the desktop computers. It does not require commercial CAD systems to visualize 3D assembly data. Real-time interference and fitness checks, dimensional verification, and design and assembly verification are performed on the developed system. Assembly of heterogeneous models for a car is conducted to verify the effectiveness of the developed DMU system on the Internet.

• Korean Journal of Computational Design and Engineering
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• 제11권1호
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• pp.27-40
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• 2006

The exchange of parameterized feature-based CAD models is important for product data sharing among different organizations and automation systems. The role of feature-based modeling is to gonerate the shape of product and capture design intends In a CAD system. A feature is generated by referring to topological entities in a solid. Identifying referenced topological entities of a feature is essential for exchanging feature-based CAD models through a neutral format. If the CAD data contains the modification history in addition to the construction history, a matching mechanism is also required to find the same entity in the new model (post-edit model) corresponding to the entity in the old model (preedit model). This problem is known as the persistent naming problem. There are additional problems arising from the exchange of parameterized feature-based CAD models. Authors have analyzed previous studies with regard to persistent naming and characteristics for the exchange of parameterized feature-based CAD models, and propose a solution to the persistent naming problem. This solution is comprised of two parts: (a) naming of topological entities based on the object spore information (OSI) and secondary name (SN); and (b) name matching under the proposed naming.

• 한국전산유체공학회:학술대회논문집
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• 한국전산유체공학회 2007년도 추계 학술대회논문집
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• pp.120-125
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• 2007

In this paper a new cell sizing method is proposed. The new method calculates cell size at a point using given size control elements directly without the aid of background grid as other cell sizing algorithms do. The calculation method and related definitions are described in detail, and typical cell sizing results are given.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 한국정밀공학회 1996년도 춘계학술대회 논문집
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• pp.798-802
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• 1996

최근 생산 현장에서의 CAD/CAM 등을 통한 자동화 확대와 더불어 이에필요한 설계 및 가공시스템의 수요도 증가하고 있다. 그러나 국내에서 사용중인 기계 및 관련 분야의 CAD/CAM 시스템은 대부분이 외국 제품이다. 근래 국내 몇몇 업체에서 독자 적인 제품을 보급하고 있으나 아직도 저조한 실정이다. 더우기 이들 제품의 대부분도 기본적인 핵심 기술 및 이론은 외국의 것을 도입한 경우가 많다. 그러므로 현재 설계 및 가공시스템의 국산화가 매우 절실하며, 또한 기본 배경이 되는 기하 라이 브러리와 모델링 엔진의 개발이 시급히 요구된다.

• Journal of the Korean Institute of Telematics and Electronics A
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• 제28A권9호
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• pp.692-699
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• 1991

In this paper, graphical representations of parameter variations affected by series or parallel feedback in the load plane were studied. As a result of transformations, all parameters of 2-port was converted to circles, and the step of noise circles and gain circles was 0.1 dB and 1dB, respectively. Compared with conventional commercial CAD softwares, the circuit design procedures could be verified much more systemically. This CAD was programmed in C-language and executed in IBM-PC with VGA graphic adaptor.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 한국정밀공학회 2008년도 추계학술대회 논문집
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• pp.481-482
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• 2008

• Journal of the KSME
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• 제25권3호
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• pp.191-197
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• 1985

시장조사나 사용자의 주문으로부터 기본계획도를 작성 이로부터 원안도를 작성 이 원안도에 대한 여러 가지 분석과 평가를 거쳐 최종적으로 원안도를 확정, 이로부터 상세부품도, 조립도를 그리게 된다. 이와같은 설계시스템 중, 현재 CAD화가 어느 정도 이루어지고 있는 공정은 E, F, G등 구조계산부분 및 J, K의 도며제도 공정 정도이다. 본란에서 다루고자 하는 설계방법론은 "B"의 기본계획도 작성공정의 CAD화를 위한 것이다. 이러한 설계방법론을 확립하기 위하여는 우선 공작기계의 구조형태를 어떠한 방법으로 기술한 것인가가 문제가 되며 이하에서 이러한 공작기계 구조형태의 기술방법과 이를 응용한 공작기계의 구조형태의 설계방법론에 관하여 살펴 보고자 한다.살펴 보고자 한다.

• Journal of Technologic Dentistry
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• 제33권2호
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• pp.137-145
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• 2011

Purpose: To evaluate the accuracy of zirconia copings in terms of clinical verified for the clinical application of CAD/CAM. Methods: Zirconia copings (n=5) were prepared using CAD/CAM system and were sintered using the relevant electrical induction furnace, which uses a 2h sintering program with a maximum temperature of $1500^{\circ}C$. The copings placed at the models and the interval values were measured. Results: The meas interval values between the die and the zirconia copings were $44.14{\mu}m$(A), $44.57{\mu}m$(B), $44.72{\mu}m$(C). 51.05 ${\mu}m$(D). Conclusion: The maximum interval values between the die and the zirconia copings were $51.3{\mu}m$ which is acceptable for clinical use. ${\mu}m$ Proper understanding of the test conditions will help enhancing the accuracy of zirconia coping.