• 한국기계연구소 소보
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• 통권19호
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• pp.149-154
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• 1989

Generally Cam-Follower systems consist of two elements: Cam is for rotating motion and follower for reciprocating motion. Depending on the shape of cam and type of follower, the motion of cam-follower system is determined. Thus design process and analysis process must be well defined. The design process means to find the coordinates of cam shape which can be defined the given motion of follower and the analysis process means to determine the motion curve of follower corresponding to the given cam based on the dimensions of a cam-follower system. This paper consists of two parts: One is development of a numerical method for design and analysis of cam-follower systems, the other is for development of a CAD program and its application. As the first part of the paper, an iterative contact method is proposed. This method can calculate the contact points between cam and roller and determine their contact angles iteratively. The second part of the paper presents the structure of a CAD program and its availability to the industrial applications.

• 한국자동차공학회논문집
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• 제17권5호
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• pp.7-15
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• 2009

This paper introduces a new variable valve actuation mechanism with movable second cam center. Valve lift and open duration can be continuously varied according to engine speed and load conditions. A new method to analyze the kinematic relations between the first and second cam profiles and valve motion are also introduced. Because of rocker motion of the second cam, conventional motion conversion program could not be used in this problem. An example shows continuous variations of valve motion and adequate ramp incorporation throughout all valve lift modes. Valve acceleration profile at the high lift mode is similar to that of conventional valvetrains. Contact geometry analysis of the mechanism gives basic information on the load conditions between the components.

• 한국기계연구소 소보
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• 통권19호
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• pp.155-161
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• 1989

Generally cam-follower systems consist of two elements: Cam is for rotating motion and follower for reciprocating motion. Depending on the shape of cam and type of follower, the motion of cam-follower system is determined. Thus design process and analysis process must be well defined. The design process means to find the coordinates of cam shape which can be defined the given motion of follower and the analysis process means to determine the motion curve of follower corresponding to the given cam based on the dimensions of a cam-follower system. This paper consists of two parts : One is for development of a numerical method for design and analysis of cam-follower systems, the other is for development of a CAD program and its application. As the second part of the paper, the structure of a CAD program is introduced. Four data files are used in the program where the design process and the analysis process are carried out interactively to en hence its availability to the industrial applications. The first part of the paper 'presents the iterative contact method which can determine the contact points and their angles between cam and roller.

• 보건교육건강증진학회지
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• 제20권4호
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• pp.27-40
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• 2003

Objective： To determine second, third and fourth-year medical students' opinions and knowledge related to complementary and alternative medicine (CAM) in a school with no requirement or elective course on the subject. Study Design： A questionnaire was offered to second, third and fourth-year medical students of the Medical College of Kosin University from August 7th, through August 30th, 2003. Results： Most students had been exposed to CAM therapies, knew that the majority of the South Korean public was using CAM, believed that some CAM interventions were useful, and did not believe CAM therapies were a threat to public health. Only one fifth of the students(22.5％) disagreed that they had to have requirement or elective course on CAM in their curriculum. Most students had insufficient knowledge or understanding of the safety or lack of it for ten of the more common CAM modalities. Most respondents thought these interventions were useful, but would not refer a patient nor dissuade a patient from seeking out such interventions. Conclusion： Medical students in this school self-identified an interest about the clinical usefulness of ten CAM modalities, but did not have sufficient knowledge about the safety for ten of the more common CAM modalities. Including CAM topics in the medical school curriculum would better prepare physicians to respond to patient inquiries about CAM and thereby to fulfill their role as patient advocates.

• 한국결정성장학회지
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• 제22권5호
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• pp.223-226
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• 2012

이종(異種)금속을 접합 가공하는 모꾸메가네기법, 상감기법 등의 기존 제작 방식은 주얼리 대량생산에 있어 표현 및 제작 상 많은 제한이 따른다. 이를 극복하기 위하여 기존의 정밀주조기법과 CAD/CAM방식을 융합한 다중(多重)주물 제작기법을 제시하였다. 주얼리 원본제작에 있어 CAD/CAM을 활용하여 2차 원본은 1차 원본보다 5 % 작게 제작하였다. 1차 황동 주조물에 2차로 은을 주조하여 실험하였으며, 2차 주조 시 통상적 주조의 플라스크 온도 보다 약 $150{\sim}200^{\circ}C$ 높게 주조하였다. 다중주물 방식을 통하여 대량생산이 가능한 이종(異種)금속의 주얼리를 손쉽게 제작할 수 있었다.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1987년도 한국자동제어학술회의논문집; 한국과학기술대학, 충남; 16-17 Oct. 1987
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• pp.269-272
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• 1987

This paper is concerned on kinematic analysis and simulation of an automatic feeding mechanism subjected by the motion of a curvilinear inverse cam. The main objection is the development of computer-aided design (CAD) program for simulating the motion of the cam-feeding mechanism using computer-graphics. A computer program CACAFS (Computer-Aided Cam and Automatic Feeding System) is independent of computer hardware used. The program is also interactive using a menu-selection technique. As the second part of the paper for the motion simulation of the cam-feeding system, this paper discusses the state-of-art for CAD. The first part of the paper presents the algorithm to simulate the notion of the cam-feeding mechanism.

• 구강회복응용과학지
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• 제32권2호
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• pp.141-148
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• 2016

Computer-aided technology는 최근 치과 치료의 흐름이다. DENTCA$^{TM}$ CAD/CAM denture (DENTCA Inc.)는 상용화된 computer-aided design/computer-aided manufacturing (CAD/CAM) 의치 시스템 중 하나로, 한 번의 내원을 통해 의치 제작에 필요한 환자의 모든 정보를 획득하여, 이 정보를 컴퓨터에 저장하고 3D 프린팅을 통해 두 번째 내원 시에 의치 장착을 목표로 한다. 현재까지 여러 증례들은 총의치 제작에 대한 CAD/CAM system의 임상적 적용을 시험해 보았다. 본 증례는 두 명의 환자에서 DENTCA system을 이용한 의치와 전통적인 방법을 이용한 의치를 동시에 제작하여 DENTCA system의 효용성과 한계점을 고찰하였다.

• 대한치과보철학회지
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• 제58권1호
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• pp.42-49
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• 2020

무치악 환자에게서 의치의 제작은 통상적이고 전통적인 방법을 따를 경우 최종 의치 장착까지 여러 단계를 거쳐야 하며 이로 인한 환자의 잦은 내원이 불가피하다. 또한 기공 과정 상에서 나타나는 중합수축에 의한 오차나, 의치의 파절이나 분실 시 빠른 재제작의 어려움 등의 단점이 존재하였다. 하지만 최근 치과 분야에서 computer-aided design and computer-aided manufacturing (CAD/CAM) System이 사용되기 시작하였고, 의치 제작에까지 그 영역을 넓히기 시작하였다. CAD/CAM System을 이용하여 의치를 제작하면 첫 번째 내원 시에 인상채득과 악간관계의 기록, 인공치의 선택 등이 동시에 이루어지고 두 번째 내원 시 의치의 장착이 가능하기 때문에 환자의 내원 횟수와 진료시간을 감소시킬 수 있다. 또한 3D-Printing 기술을 이용하기 때문에 중합수축에 의한 기공 오차를 감소시킬 수 있다. 현재 상용화 되어 있는 CAD/CAM System을 사용한 의치로는 DENTCA CAD/CAM denture (DENTCA Inc., Los Angeles, CA, USA)가 있다. 본 증례에서는 상, 하악 완전 무치악 환자에게서 conventional 한 방법과 DENTCA CAD/CAM Denture System을 사용하는 방법을 동시에 사용하여 두 쌍의 총의치로 수복함으로써 발음, 저작, 연하 등의 기능적인 측면뿐만 아니라 심미적인 측면에서도 양호한 결과를 얻었기에 이를 보고하고자 한다.

• International Journal of Precision Engineering and Manufacturing
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• 제6권4호
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• pp.8-13
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• 2005

Interoperability has been the problem of CAD/CAM systems. Starting from 1980's, national and international organizations have addressed the issue through development and release of standards for the exchange of geometric and nongeometric design data. To CAD/CAM vendors, the task of interpreting and implementing these standards falls into their products. This task is a balancing action between users' needs, available development resources, and the technical specifications of standards. This paper explores an area of CAD/CAM systems development, particularly the implementation of the effective exchange files translators'. A new approach is introduced, which proposes to enclose all the translation operations concerning each exchange format to a separate DLL, thus making a 'plug-in.' Then, this plug-in could be used together with the CAD/CAM system or with specialized translation software. This approach allows to create new translators rapidly and to gain the reliable, high-efficiency, and reusable program code. The second part of the paper concerns the possible problems of translators' development. These difficulties often come from the exchange standards' misunderstanding or ambiguity in standards. All examples come from the authors' practice experiences of dealing with CAD/CAM systems.

• 구강회복응용과학지
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• 제40권2호
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• pp.100-106
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• 2024

조기 교정치료의 개입은 종종 성장하는 치열을 정상 교합으로 유도하는 것에서부터 시작된다. 유치의 상실로 인한 맹출 실패를 예방하는 가장 간단한 방법은 밴드 및 루프와 같은 공간 유지장치를 부착하는 것이다. 밴드 및 루프 공간 유지장치는 밴드의 픽업 인상 과정을 거쳐야 하며, 시멘트 소실과 탈회, 인접치의 locking과 같은 문제들을 갖고 있다. 이러한 문제를 해결하기 위해서 CAD/CAM을 이용한 band가 필요 없는 공간유지장치가 개발되었다. 본 증례는 밴드 없이 CAD/CAM을 이용하여 하악 제2소구치가 성공적으로 맹출할 수 있었기에 이를 보고하는 바이다.