• Title/Summary/Keyword: 형상특징

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A feature data model in milling process planning (밀링 공정설계의 특징형상 데이터 모델)

  • Lee, Choong-Soo;Rho, Hyung-Min
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.21 no.2
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    • pp.209-216
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    • 1997
  • A feature is well known as a medium to integrate CAD, CAPP and CAM systems. For a part drawing including both simple geometry and compound geometry, a process plan such as the selection of process, machine tool, cutting tool etc. normally needs simple geometry data and non-geometry data of the feature as the input. However, a extended process plan such as the generation of process sequence, operation sequence, jig & fixture, NC program etc. necessarily needs the compound geometry data as well as the simple geometry data and non-geometry data. In this paper, we propose a feature data model according to the result of analyzing necessary data, including the compound geometry data, the simple geometry data and the non-geometry data. Also, an example of the feature data model in milling process planning is described.

Automatic generation of NC-code using Feature data and Process Planning data (특징형상정보와 작업설계정보를 이용한 NC코드의 자동 생성)

  • 박재민;노형민
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 2002.10a
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    • pp.591-594
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    • 2002
  • Generating NC-code from 3D part model needs a lot of effort to make many decisions, including machining area, tool change data, tool data, cutting condition, etc., by using either manual or computer aided method. This effort can be reduced by integration of automated process planning and NC-code generation. In case of generating NC code with a help of the process planning system, many data mentioned from the process planning can be used. It means that we can create NC-code about a full part. In this study, integration of FAPPS(Feature based Automatic Process Planning) with a NC-code generating module is described and additional data to adapt NC-code for machine shop is discussed.

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Reference Feature Based Cell Decomposition and Form Feature Recognition (기준 특징형상에 기반한 셀 분해 및 특징형상 인식에 관한 연구)

  • Kim, Jae-Hyun;Park, Jung-Whan
    • Korean Journal of Computational Design and Engineering
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    • v.12 no.4
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    • pp.245-254
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    • 2007
  • This research proposed feature extraction algorithms as an input of STEP Ap214 data, and feature parameterization process to simplify further design change and maintenance. The procedure starts with suppression of blend faces of an input solid model to generate its simplified model, where both constant and variable-radius blends are considered. Most existing cell decomposition algorithms utilize concave edges, and they usually require complex procedures and computing time in recomposing the cells. The proposed algorithm using reference features, however, was found to be more efficient through testing with a few sample cases. In addition, the algorithm is able to recognize depression features, which is another strong point compared to the existing cell decomposition approaches. The proposed algorithm was implemented on a commercial CAD system and tested with selected industrial product models, along with parameterization of recognized features for further design change.

A Study on License Number Plate Extraction in a Car Image and Recognition (자동차 영상에서의 번호판 추출과 문자 인식에 관한 연구)

  • Nam, Kee-Hwan;Bae, Cheol-Soo;Na, Sang-Dong
    • Proceedings of the Korea Information Processing Society Conference
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    • 2002.04a
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    • pp.713-716
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    • 2002
  • 자동차의 번호판은 각각의 차량을 추분 할 수 있는 것으로, 번호판의 문자를 인식함으로써 전국에 등록되어 있는 모든 차량 중에 1 대를 폭정 지을 수 있다. 그러나 기존의 연구방법 대부분은 번호판 문자 중에서 큰 숫자 4개만을 인식하는 것으로 전국적인 규모에서 완전한 차량인식이 불충분하였다. 따라서 본 논문에서는 차량의 정면에서 촬영한 영상에서 번호판을 추출하고, 그 안에 표기된 모든 문자를 인식하는 방법을 제안한다. 본 연구에서 사용된 방법은 허프변환과 번호판의 형상특징을 이용하여 번호판영역을 추출하고, 추출된 번호판에서 문자의 위치적 특징을 사용하여 각 문자를 추분하고 인식하였다. 160장의 샘플사진으로 실험해 본 결과 번호판 영역을 추출하고, 문자인식을 모두 성공한 종합성공률은 87.5%의 결과를 나타내었다.

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A Study on the Development of Knowldege-based Computer Aided Manufacturing System for Mold Manufacturing(1) -On the modelling of feature based model and database processing with knowledge- (금형 가공용 지식기반 CAM 시스템의 개발에 관한연구 (1) -특징 형상 모델링 및 짓기 베이스화에 관하여 -)

  • 정재현
    • Journal of Advanced Marine Engineering and Technology
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    • v.23 no.5
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    • pp.622-629
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    • 1999
  • This paper presents the development of an interactive knowledge-based CAM system for design-ing and manufacturing the mold. The system is composed of two functional parts. One is the geo-metric modeller that uses the feature-based models. The models include base plate step, hole, pocket, boss and slot, These are designed by interactive user interface. The other is the expert sys-tem module with inference engine and knowledge database of workpiece material tools manufac-turing machines process an working conditions. With two parts the final mold shape is generated with manufacturing information for effective production.

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Generative Process Planning through Feature Recognition (특징형상 인식을 통한 창성적 자동 공정계획 수립 - 복합특징형상 분류를 중심을 -)

  • 이현찬;이재현
    • Korean Journal of Computational Design and Engineering
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    • v.3 no.4
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    • pp.274-282
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    • 1998
  • A feature is a local shape of a product directly related to the manufacturing process. The feature plays a role of the bridge connecting CAD and CAM. In the process planning for he CAM, information on manufacturing is required. To get the a manufacturing information from CAD dat, we need to recognize features. Once features are recognized, they are used as an input for the process planning. In this paper, we thoroughly investigate the composite features, which are generated by interacting simple features. The simple features in the composite feature usually have precedence relation in terms of process sequence. Based on the reason for the precedence relation, we classify the composite features for the process planning. In addition to the precedence relation, approach direction is used as an input for the process planning. In the process planning, the number of set-up orientations are minimized whole process sequence for the features are generated. We propose a process planning algorithm based on the topological sort and breadth-first search of graphs. The algorithn is verified using sample products.

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Study of Registration of 3D Data by Using the Feature on Products (제품의 특징형상을 이용한 3차원 데이터의 레지스트레이션 방안 연구)

  • Kim, Min-Seok;In, Jae-Jun;Lee, Eun-Gi
    • Transactions of the Korean Society of Machine Tool Engineers
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    • v.17 no.4
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    • pp.140-145
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    • 2008
  • Recently more complex geometric shapes, including freeform surfaces, are adopted for the design of products to emphasize style or beauty. Modeling of these products is extremely difficult or often impossible. Reverse engineering is the latest technology that can solve the problem by generating CAD models from the physical mockups or prototype models. Reverse engineering uses the coordinate measuring machine(CMM) to get the shape data of products. CMM is limited by the size of the product; therefore it must need the feature to solve it. The tooling-ball which is generally used for feature has difficulty in being used for soft products. Besides, the higher the accuracy of the tooling-ball is, the more expensive its cost is. This study will develop the feature of high accuracy without additional tools and compare the difference of accuracy by it.

Standard Operation Time Estimation Using Features in Mold Die Manufacturing (특징형상을 사용한 사출금형 표준 가공공수계산)

  • 이충수;노형민
    • Transactions of the Korean Society of Mechanical Engineers
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    • v.18 no.1
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    • pp.223-231
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    • 1994
  • When manufacturing mold dies, an operation sheet is required for each part of the mold dies. The consistent estimation of standard operation time in the operation sheet is difficult, because the estimation is mainly based on subjective judgement. In order to resolve it, concept of feature is introduced in this study. For CAD/CAPP integration, feature technology is being implemented to represent geometrical and technological information of part drawings. A feature database has already been designed, and then used to generate data for process and operation planning modules. Related to this former research, standard operation time is calculated using the feature information and tables used in a real factory.

Quantitation of Pulmonary Nodule's Border Structure by Means of Fourier Transform by using Chest X-ray CT Images (흉부 X선 CT 화상을 이용한 푸리에 변환에 의한 폐종류의 경계 형상의 정량화)

  • 김응규;권영도
    • Proceedings of the IEEK Conference
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    • 2000.06d
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    • pp.135-138
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    • 2000
  • 흉부 X선 CT 화상을 이용한 폐종류의 경계 형상을 정량적으로 평가하기 위하여 푸리에 변환된 폐종류 음영의 윤곽선 내 power spectrum 고주파 성분의 총합이 폐종류 음영의 경계 형상에 관한 유효한 평가 값이 되는지의 여부를 검토하였다. 이 평가 값은 폐종류 음영의 CT 화상 위의 특징을 명확히 반영한다고 판단된다. 다시 말해서, 윤곽선은 양성 혹은 악성 종류에 있어서 각각 명확하거나 불투명하다. 양성 IS명과 악성 16명인 환자 31명에 대해서 이 평가 값을 계산하여 통계적 처리를 행한 결과 양성과 악성 간에 뚜렷한 차이를 인식할 수 있었다. 이러한 제안된 평가 방법에 의해, power spectrum 고주파 성분의 총합이 폐종류 경계 형상의 평가치가 되어, 정량적인 폐종류의 양성과 악성 감별을 행할 때 유용한 값이 될 가능성을 시사한다고 볼 수 있다.

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Quantitation of Pulmonary Nodule's Border Structure by using Chest X-ray CT Images (흉부 X선 CT 화상을 이용한 폐종류(肺腫瘤) 경계 형상의 정량화)

  • Kim, Eung-Kyeu
    • Proceedings of the KIEE Conference
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    • 2000.07d
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    • pp.2924-2926
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    • 2000
  • 흉부 X선 CT 화상을 이용한 폐종류(肺腫瘤)의 경계 형상을 정량적으로 평가하기 위하여 푸리에 변환된 폐종류(肺腫瘤) 음영의 윤곽선 내 power spectrum 고주파 성분의 총합이 폐종류 음영의 경계 형상에 관한 유효한 평가 값이 되는지의 여부를 검토하였다. 이 평가 값은 폐종류(肺腫瘤) 음영의 CT 화상 위의 특징을 명확히 반영한다고 판단된다. 양성 15명과 악성 16명인 환자 31명에 대해서 이 평가 값을 계산하여 통계적 처리를 행한 결과 양성과 악성 간에 뚜렷한 차이를 인식할 수 있었다. 이러한 제안된 평가 방법에 의해, power spectrum 고주파 성분의 총합이 폐종류(肺腫瘤) 경계 형상의 평가치가 되어, 정량적인 폐종류(肺腫瘤)의 양성과 악성 감별을 행할 때 유용한 값이 될 가능성을 시사한다고 볼 수 있다.

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