• Title/Summary/Keyword: CAD

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CAD/CAM의 초보지식

  • 김재정
    • Journal of the KSME
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    • v.32 no.2
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    • pp.134-145
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    • 1992
  • CAD/CAM의 초보지식을 부분적이나마 간략히 소개해 보았다. CAD/CAM에서 기하형상기술이 차지하는 비중과 이 기술의 한계점을 논의해 보았고, 설계에서 필수인 설계 지식이 CAD시스템에 융합되기 어려움을 실제의 예를들어 소개해 보았다. 마지막으로 현재의 CAD시스템이 기계전체 차원에서의 설계 도구이기보다 부품설계 차원에서의 도구임을 알아보았다. 현재까지 CAD시스 템이 설계과정에서 별로 창의력이 요구되지 않는, 그렇지만 많은 시간이 소요되는 도면 작업을 간편화하게 한 것으로도 CAD가 설계자동화에 큰 몫을 담당해 왔다고 볼 수 있다. 앞으로 미래의 CAD 방향은 인간의 창의력을 도와주는 곳으로 나가야함을 자명한 사실이라 본다.

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Regulation of Cinnamyl Alcohol Dehydrogenase (CAD) Gene Family in Lignin Biosynthesis (리그닌 생합성에서 cinnamyl alcohol dehydrogenase (CAD) 유전자 family의 조절)

  • Kim, Young-Hwa;Huh, Gyung-Hye
    • Journal of Life Science
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    • v.31 no.10
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    • pp.944-953
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    • 2021
  • Lignin is a complex phenylpropanoid polymer abundant in the cell walls of vascular plants. It is mainly presented in conducting and supporting tissues, assisting in water transport and mechanical strength. Lignification is also utilized as a defense mechanism against pathogen infection or wounding to protect plant tissues. The monolignol precursors of lignin are synthesized by cinnamyl alcohol dehydrogenase (CAD). CAD catalyzes cinnamaldehydes to cinnamyl alcohols, such as p-coumaryl, coniferyl, and sinapyl alcohols. CAD exists as a multigenic family in angiosperms, and CAD isoforms with different functions have been identified in different plant species. Multiple isoforms of CAD genes are differentially expressed during development and upon environmental cues. CAD enzymes having different functions have been found so far, showing that one of its isoforms may be involved in developmental lignification, whereas others may affect the composition of defensive lignins and other wall-bound phenolics. Substrate specificity appears differently depending on the CAD isoform, which contributes to revealing the biochemical properties of CAD proteins that regulate lignin synthesis. In this review, details regarding the expression and regulation of the CAD family in lignin biosynthesis are discussed. The isoforms of the CAD multigenic family have complex genetic regulation, and the signaling pathway and stress responses of plant development are closely linked. The synthesis of monolignol by CAD genes is likely to be regulated by development and environmental cues as well.

CAD Data Exchange among Different Commercial Packages (이 기종 시스템간의 CAD 데이터 교환)

  • Kim, Tae-Wook;Hwang, Byeong-eok
    • Journal of the Korean Society of Industry Convergence
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    • v.7 no.4
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    • pp.377-382
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    • 2004
  • This research was about implementing STEP for data exchange among different commercial package(CAD system). STEP was used to share CAD data as follows. ST-Developer implement Solid model was used with a physical file of STEP and represented in a CAD system. And then STEP conversion utility was used to make a neutrality format form in a component modeling. Analysis of Solid model was made possible for CAD system to read in and analyzed Solid model. This research are summarized as follows 1. A basis Model development used Visual C++ for a neutrality data of a programming interface general-use CAD system, and produced Box and Cylinder to a physical file, the result was implemented this in a programming interface to general-use CAD system, it is represented in CAD system as identical one modeling object. 2. STEP was used in different CAD system to utilize to its of each CAD system maximum, CATIA V5R9 user was able to analyze MDT 6 Modeling Arm. 3. STEP was used able to interpret and remodel the existing Solid model.

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Identification of the Vibrio vulnificus cadC and Evaluation of Its Role in Acid Tolerance

  • Rhee, Jee-Eun;Ju, Hyun-Mok;Park, U-Ryung;Park, Byoung-Chul;Choi, Sang-Ho
    • Journal of Microbiology and Biotechnology
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    • v.14 no.5
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    • pp.1093-1098
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    • 2004
  • An open reading frame encoding CadC, consisting of 526 amino acids, was identified from the upstream region of the Vibrio vulnificus cadBA operon. The deduced amino acid sequences of the cadC were 22 to 78% similar to those reported from other Enterobacteriaceae. Functions of cadC gene on acid tolerance were assessed by comparing acid tolerances of V. vulnificus and its isogenic mutant, whose cadC gene was inactivated by allelic exchanges. The results demonstrated that the gene product of cadC contributes to acid tolerance of V. vulnificus, and that its contribution is dependent on prior exposure of cells to moderately acidic pH. The cellular level of cadB and cadA transcripts decreased in the cadC mutant, indicating that CadC exerts its effect on acid tolerance of V. vulnificus by enhancing the expression of cadBA in a pH-dependent manner.

Editing Depression Features in Static CAD Models Using Selective Volume Decomposition (선택적 볼륨분해를 이용한 정적 CAD 모델의 함몰특징형상 수정)

  • Woo, Yoon-Hwan;Kang, Sang-Wook
    • Korean Journal of Computational Design and Engineering
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    • v.16 no.3
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    • pp.178-186
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    • 2011
  • Static CAD models are the CAD models that do not have feature information and modeling history. These static models are generated by translating CAD models in a specific CAD system into neutral formats such as STEP and IGES. When a CAD model is translated into a neutral format, its precious feature information such as feature parameters and modeling history is lost. Once the feature information is lost, the advantage of feature based modeling is not valid any longer, and modification for the model is purely dependent on geometric and topological manipulations. However, the capabilities of the existing methods to modify static CAD models are limited, Direct modification methods such as tweaking can only handle the modifications that do not involve topological changes. There was also an approach to modify static CAD model by using volume decomposition. However, this approach was also limited to modifications of protrusion features. To address this problem, we extend the volume decomposition approach to handle not only protrusion features but also depression features in a static CAD model. This method first generates the model that contains the volume of depression feature using the bounding box of a static CAD model. The difference between the model and the bounding box is selectively decomposed into so called the feature volume and the base volume. A modification of depression feature is achieved by manipulating the feature volume of the static CAD model.

An Efficient Algorithm for Rebar Element Generation Using 3D CAD Data (3D CAD 데이터 기반의 효율적 철근 요소 생성 알고리즘)

  • Cho, Kyung-Jin;Lee, Jee-Ho
    • Journal of the Computational Structural Engineering Institute of Korea
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    • v.22 no.5
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    • pp.475-485
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    • 2009
  • In this paper a two-step algorithm is proposed to efficiently generate rebar elements from 3D CAD data in the context of CAD/CAE data transfer. The first step is an algorithm to identify various type rebar objects and their attributes by analyzing 3D CAD data in STEP format, which is one of the international data standards. The second algorithmic step is a procedure to generate one-dimensional rebar elements from the object data made through the first step for finite element analysis or other CAE tasks. Successful rebar element data generation from real 3D CAD data for a reinforced concrete structure shows the efficacy of the proposed algorithm.

The Trends of Computer Aided Design in the Clothing and Textiles Programs in U.S.A. Colleges & Universities (의류학관련 학과에서의 CAD의 경향 - 미국내 대학을 중심으로 -)

  • Choi, Hyun Joo
    • Journal of the Korean Society of Clothing and Textiles
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    • v.17 no.4
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    • pp.638-647
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    • 1993
  • 현재 미국에서 컴퓨터 디자인(Computer aided design)은 의류산업과 의류학 교육에 중요한 역할을 하고 있다. 그러나 한국내 의류학관련 학과에서의 CAD의 도입은 아직 초기 단계에 불과하다. 이에 본 연구는 미국내 대학을 중심으로 의류학관련 학과에서의 전반적인 CAD 교육 경향을 조사 분석하여 실질적인 자료와 국내 의류학관련 학과의 CAD 교육의 나아갈 방향을 제시하는데 그 목적이 있다. 1993년 5월, 총 19문항의 질문지가 124개 대학 의류학관련 학과에 우편으로 배포되었으며 71부가 회수되어 57%의 회수율을 나타내었다. 그 결과는 다음과 같다. 조사 대상(71개 학교)중 56%가 CAD를 커리큘럼에 포함시켰다. 특히 의상디자인 전공을 가진 학과의 79%가 CAD를 도입하여, 의상디자인 전공이 없는 학과(28%가 CAD를 도입)보다 그 비율이 훨씬 높았다. 의류학 교육에서 CAD의 도입은 1988년 이후 급격한 증가 추세를 보였으며, 대부분의 강의는 의류학분야 교수진에 의해, 의류학과 시설물내에서 이루어졌다. CAD를 독립된 과목으로 강의하는 경우 대부분 필수과목으로서 한 학기 코오스가 많았으며 3학년부터 시작되었다. CAD를 다른 의류학 과목에 포함시켜 일부분으로 강의할 경우 영역 별로는 복식 의장학 분야의 과목에, 시간 별로는 한 학기 중 "몇 주" 정도로 가르치는 경우가 가장 많았다. 전체 CAD 강의에서 다루는 주제로는 패턴 메이킹이 가장 많이 차지하였으며 그 다음에는 패턴 그레이딩, 마커 메이킹, 직물/패턴 디자인, 패션 일러스트레이션, 의상디자인 순이며 스토어 레이아웃 상품전시 및 디스플레이 계획이 가장 적었다. 본 연구 결과는 현재 CAD를 강의하고 있거나 앞으로 CAD를 커리큘럼에 도입하려는 한국 의류학 분야 교육자에게 유용한 정보를 제공할 수 있을 것으로 기대된다.

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A Study on the Educational Situation of Apparel CAD of Clothing Related Department (의류관련학과의 어패럴 CAD교육실태에 관한 연구)

  • 이정순;한경희
    • The Research Journal of the Costume Culture
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    • v.10 no.5
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    • pp.542-554
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    • 2002
  • The purposes of this study were to investigate, analyze, and consider the feature and practical situation of Apparel CAD education and distribution situation of CAD system so that CAD education can be effectively operated and managed in various kinds of relevant schools and universities. 32 colleges and universities that are performing CAD educational system are selected for the study. The author of the study has investigated and obtained the information through questionnaires to 32 professors who are in charge of CAD lectures and 301 students who are receiving CAD education. The result is as follows. 1. It showed that 62.5% of CAD educational systems have been practically introduced after 1995. Regarding the using system, YUKA occupies 46.9%, PAD 21.8%, and GERBER 18.8% and these three kinds of system have been chiefly supplied. 40.6% of them own only one system, 37.5% of them own 2~5 systems and 78% of them own less than 5 systems. 2. The most seriously pointed problems during the operation of CAD system were the lack of experimental materials and the frustration of manpower supply. Thus, the CAD education programs in schools and universities are practiced in inferior environments internally and externally. 3. Regarding the practical situation of CAD education, 28 among 32 schools and universities are performing CAD as one of the regular subjects for the curriculum. 4. Regarding satisfaction degree of the using system, professors showed higher satisfaction degree than students did. In conclusion, it showed that although the practical situations of CAD education in schools and universities have been changed and improved so much since 1995 owing to the increase of the positive recognition of the necessity of CAD, many students in the educational sites cannot study their favorite subjects related with CAD program with interest due to the lack of experimental facilities, the poor computer management systems, and the problems of manpower supply, etc.

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CAD S/W 개발사례: MagicCAD

  • Kim, Ho
    • CDE review
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    • v.2 no.1
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    • pp.44-47
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    • 1996
  • 국내에서 오래전부터 몇몇 CAD S/W들이 개발되었고 지금도 이와 같은 노력은 계속되고 있는 상황이다. 본 고에서는 삼성에서 개발한 MagicCAD의 개발과정에 있었던 여러가지 사항을 특별한 제약없이 기술하고 MagicCAD의 몇몇 특징을 소개하고자 한다. MagicCAD는 현재 삼성 그룹내 전자 계역 회사들(삼성전자, 삼성전관, 삼성전기 등) 위주로 1000여 copy가 현업에서 사용중에 있다.

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A Study on an Extended Knowledge Model and a Management System of an Intelligent CAD System using UG/KF (UG/KF를 이용한 지능형 CAD 시스템의 지식 확장 및 지식 관리에 관한 연구)

  • Bae I.J.;Lee S.H.;Chun H.J.
    • Korean Journal of Computational Design and Engineering
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    • v.10 no.1
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    • pp.49-60
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    • 2005
  • Existing CAD systems have configured geometry data and it is necessary to extend the configured geometry into a knowledge-based system. An intelligent CAD system emerged to provide such a knowledge-based system. However the intelligent CAD system has a limited product model to represent various knowledge models. This paper presents a model, called extended intelligent CAD model, which can extend the product model of the intelligent CAD system into further detailed knowledge model. The extended intelligent CAD model includes a whole design process knowledge and an efficiency of the model has been verified via a knowledge based wiper design system. The model can improve the functionality and efficiency of the existing CAD systems.