• 제목/요약/키워드: shape error

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3차원 안면자동인식기의 형상복원 오차검사 (An Error Examination of 3D Face Automatic Recognition)

  • 석재화;조경래;조용범;유정희;곽창규;이수경;고병희;김종원;김규곤;이의주
    • 사상체질의학회지
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    • 제18권2호
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    • pp.41-49
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    • 2006
  • 1. Objectives The Face is an important standard for the classification of Sasang Contitutions. We are developing 3D Face Automatic Recognition Apparatus to analyse the facial characteristics. So We should examine a shape demobilization error of 3D Face Automatic Recognition Apparatus. 2. Methods We compared facial shape data be demobilized by 3D Face Automatic Recognition Apparatus with facial shape data that be demobilized by 3D laser scanner. The subject was two korean men. And We analysed the average error and the maximum error of two data. In this process, We used one datum point(the peak of nose) and two datum line(vertical section and horizontal section). 3. Results and Conclusions In each this comparison, the average error of vertical section was 1.962574mm and 2.703814mm. and the maximum error of vertical section was 16.968249mm and 18.61464mm. the average error of horizontal section was 4.173203mm and 21.487479mm. and the maximum error of horizontal section was 3.571210mm and 17.13255mm. Also We complemented this apparatus a little and We reexamined a shape demobilization error of 3D Face Automatic Recognition Apparatus again. Accuracy of a shape demobilization was improved a little. From now on We complement accuracy of a shape demobilization in 3D Face Recognition Apparatus.

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공작기계의 이송계 제어 시스템의 최적화 (Optimization of Motion Control System on the Machine Tool)

  • 박인준;곽경남;백형래
    • 전력전자학회:학술대회논문집
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    • 전력전자학회 1997년도 전력전자학술대회 논문집
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    • pp.336-340
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    • 1997
  • This paper is a study about motor technic of motion and feedforward control in order to shape cutting control on the machine tool. The shape error caused by delay of the servo system in the direction of radius at the time of circular cutting is reduced by feedforward control, shape error generated by the position command delay is minimized by using the acceleration/deceleration time constant after the interpolation. The study was verified to optimization of motion control on experiments of a vertical machining center of the machine tool.

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특이 형상함수를 이용한 Pollution 적응 요소생성 알고리즘 (A Pollution Adaptive Mesh Generation Algorithm Using Singular Shape Functions)

  • 유형선;장준환;편수범
    • 한국전산구조공학회:학술대회논문집
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    • 한국전산구조공학회 2001년도 봄 학술발표회 논문집
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    • pp.110-118
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    • 2001
  • In many areas of finite element analysis, elements with special properties are required to achieve maximal accuracy. As examples, we may mention infinite elements for the representation of spatial domain that extend to special and singular elements for modeling point and line singularities engendered by geomeric features such as reentrant corners and cracks. In this paper, we study on modified shape function representing singular properties and algorigthm for the pollution adaptive mesh generation. We will also show that the modified shape function reduces pollution error and local error.

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측벽 엔드밀 가공에서 공구 변형을 고려한 형상 오차 예측 (Form Error Prediction in Side Wall Milling Considering Tool Deflection)

  • 류시형;주종남
    • 한국정밀공학회지
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    • 제21권6호
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    • pp.43-51
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    • 2004
  • A method for form error prediction in side wall machining with a flat end mill is suggested. Form error is predicted directly from the tool deflection without surface generation by cutting edge locus with time simulation. Developed model can predict the surface form error about three hundred times faster than the previous method. Cutting forces and tool deflection are calculated considering tool geometry, tool setting error and machine tool stiffness. The characteristics and the difference of generated surface shape in up milling and down milling are discussed. The usefulness of the presented method is verified from a set of experiments under various cutting conditions generally used in die and mold manufacturing. This study contributes to real time surface shape estimation and cutting process planning for the improvement of form accuracy.

STL의 오류수정 및 형상수정 시스템의 개발 (System Developement for STL Error Correction and Shape Modification)

  • 채희창
    • 한국정밀공학회지
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    • 제16권3호통권96호
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    • pp.53-61
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    • 1999
  • STL has several errors such as orientation error, hole error, and acute triangle error on being translated from CAD software. These errors should be corrected before using in Rapid Prototyping. So the software is necessary to correct errors. In this study, STL Editor which is a system for STL error correction and shape modification is developed and contains following characteristics. 1.Apply the triangle based data st겨cture. 2.Use the graphic user interface for easy work. 3.Use the Diet method to reduce data size. 4.Use the Delaunay triangulation method to enhance the quality of STL. 5.Modify the STL errors manually.

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광섬유 브래그 격자 센서를 이용한 복합재 외팔보의 형상 모니터링 (Shape Monitoring of Composite Cantilever Beam by Using Fiber Bragg Grating Sensors)

  • 이건호;김대현
    • 대한기계학회논문집A
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    • 제37권7호
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    • pp.833-839
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    • 2013
  • 본 논문에서는 광섬유 브래그 격자 센서를 이용한 외팔보 형태의 복합재 구조물 2차원 형상 모니터링 연구를 수행하였다. 복합재 구조물의 형상을 모니터링하기 위해 NASA에서 개발한 처짐 방정식과 FBG 센서가 부착된 복합재 보를 이용하였으며, 처짐에 따른 복합재 보의 형상을 추정하고 동시에 실제 처짐과 측정된 처짐 크기를 비교하였다. 실험 결과 보의 형상을 성공적으로 추정할 수 있었으나 실제 처짐과 측정된 처짐이 오차가 발생하였다. 하지만 이러한 오차가 선형 관계를 갖고 있어 이를 정량화하여 보정한 후 재 실험한 결과 실제 처짐과 동일한 처짐 크기를 구할 수 있었다. 결과적으로 오차 보상을 잘 활용한다면 외팔보 구조물의 형상 모니터링을 위해 FBG 센서와 처침 방정식이 매우 유용하다는 점을 확인할 수 있었다.

수명분포가 지수화-지수분포를 따르는 소프트웨어 신뢰모형 특성에 관한 연구 (A Study on the Characteristics of Software Reliability Model Using Exponential-Exponential Life Distribution)

  • 김희철;문송철
    • Journal of Information Technology Applications and Management
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    • 제27권3호
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    • pp.69-75
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    • 2020
  • In this paper, we applied the shape parameters of the exponentialized exponential life distribution widely used in the field of software reliability, and compared the reliability properties of the software using the non-homogeneous Poisson process in finite failure. In addition, the average value function is also a non-decreasing form. In the case of the larger the shape parameter, the smaller the estimated error in predicting the predicted value in comparison with the true value, so it can be regarded as an efficient model in terms of relative accuracy. Also, in the larger the shape parameter, the larger the estimated value of the coefficient of determination, which can be regarded as an efficient model in terms of suitability. So. the larger the shape parameter model can be regarded as an efficient model in terms of goodness-of-fit. In the form of the reliability function, it gradually appears as a non-increasing pattern and the higher the shape parameter, the lower it is as the mission time elapses. Through this study, software operators can use the pattern of mean square error, mean value, and hazard function as a basic guideline for exploring software failures.

Study on Estimating the Shape of a Ship by Integrating Radar Images

  • Ishiwata, Junya;Fujisaka, Takahiko;Imazu, Hayama
    • 한국항해항만학회:학술대회논문집
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    • 한국항해항만학회 2006년도 Asia Navigation Conference
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    • pp.71-78
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    • 2006
  • The image of an object obtained by the radar is not corresponding to its true shape, because the image of an object observed by the radar is receiving an influence such as multiple-reflections and expanded in bearing because of the beam width of a radar. In addition, a radio wave does not hit the entire surface of an object. Therefore, the image of the front side of a ship facing a radar antenna corresponds to its true shape. In this paper, a method to estimate a ship's shape by means of the integration of the front parts of images obtained from radars is proposed. In addition, a matter, which is observation error of each radar, in using multi-radars, and the process included in the proposed method for solving the matter, are described. As a result of the experiment, the accuracy of about 3 degrees in ship's heading and about 14 meters in length and about 9 meters in beam was obtained.

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3차원 형상 복원을 위한 재귀적 오차 성분 보정 방법 (Recursive Error-Component Correcting Method for 3D Shape Reconstruction)

  • 고성식
    • 한국정보통신학회논문지
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    • 제21권10호
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    • pp.1923-1928
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    • 2017
  • 본 연구는 행렬인수분해 기반으로 3차원 형상의 복원을 위한 오차 보정에 관한 것입니다. 기존 행렬인수분해 기반 오차 보정 방법은 전역적인 최적화로 인해 보정에 한계가 있습니다. 따라서 본 논문에서는 전역적 접근 대신 3차원 복원 형상의 주요 오차 영향 인자를 찾아 보정하는 새로운 방법을 제시하였습니다. 우리는 오차 영향 인자를 2차원 재 투영 편차 공간에서 정의하고 그 오차 성분을 직접 보정합니다. 그리고 일련의 과정을 재귀적으로 반복 적용함으로서 오차 보정 성능을 개선시킬 수 있습니다. 이러한 접근 방법은 어떤 기하학적 정보에 의존하지 않고 영향도가 가장 큰 오차 성분 중심으로 제어하기 때문에 잡음에 장점을 가지고 있습니다. 제안한 알고리즘 성능 평가는 합성과 실제 영상 프레임으로 시뮬레이션하여 잡음에 강인한 특성을 증명했습니다.

A Study of Seam Tracking and Error Compensation for Plasma Arc Welding of Corrugation Panel

  • Yang, Joo-Woong;Park, Young-Jun
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 2003년도 ICCAS
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    • pp.2701-2706
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    • 2003
  • This paper describes weld seam tracking and error compensation methods of automatic plasma arc welding system designed for the corrugation panel that consists of a linear section and a curved section with various curvatures. Realizing automatic welding system, we are faced with two problems. One is a precise seam tracking and the other is an arc length control. Due to the complexity of the panel shape, it is difficult to find a seam and operate a torch manually in the welding process. So, laser vision sensor for seam tracking is equipped for sensing the seam position and controlling the height of a torch automatically. To attain more precise measurement of an arc length, we measure the 3D shape of the panel and analyze error factors according to the various panel states and caused errors are predicted through the welding process. Using that result, compensation algorithm is added to that of arc length control and real time error compensation is achieved. The result shows that these two methods work effectively.

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