• 제목/요약/키워드: Shape Measurement

검색결과 1,745건 처리시간 0.029초

시간평균 ESPI에 의한 진동 MODE SHAPE의 계측 (MEASUREMENT OF THE VIBRATION MODE SHAPE USING THE TIME AVERAGE FSPI)

  • 최장섭;강영준;문상섭
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 1995년도 춘계학술대회 논문집
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    • pp.308-313
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    • 1995
  • Non-destructive inspection techniques using laser have been broading their application areas as well as growing their measurement skills together with the rapid development of circumferential technology like fiber optics and computer. The remarkable inspection technique using laser speckle, so-called ESPI is aleady on the stage of on-line testing with commercial products in other nations. Especially, this technique is expected to be applied to the nuclear industry. Because it is proper for the vibration measurement and it can be applied to objects of a high temperature. This paper describes the use of the ESPI system for measuring vibration patterns on the reflecting objects. Using this system, high-quality Jo fringers fso that fringe shift algorthms can be used to determine vibration interferograms recorded by the ESPI system.

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평면형 차륜 형상을 가진 탈선계수 측정용 윤축의 하중시험 (Load test of wheel-set for derailment coefficient measurement that have plane style wheel plate)

  • 함영삼;홍재성
    • 한국철도학회:학술대회논문집
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    • 한국철도학회 2004년도 추계학술대회 논문집
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    • pp.228-233
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    • 2004
  • A derailment coefficient of railway vehicle is as one of important element that estimate running safety. Derailment coefficient is ratio of lateral load/vertical load happens in contact point between wheel and rail. Lateral load increases, dangerous of derailment can rise. There are ground and vehicle to measurement method of these derailment coefficient. Method of ground is simple, but when vehicles passes data of a point, there is shortcoming that acquire locally. Curved surface style wheel shape that use so far among vehicle method in this research wishes to be not but describe about static load test of wheel-set for derailment coefficient measurement that have plane plate shape that manufacture separate way and correction result etc. to test.

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그림자식 모아레를 이용한 형상측정법의 정확도 개선에 관한 연구 (A Study on the Improvement of Accuracy of Shape Measurement in the Shadow Moire Method)

  • 박경근;박윤창;정경민
    • 한국공작기계학회:학술대회논문집
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    • 한국공작기계학회 1999년도 춘계학술대회 논문집
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    • pp.175-180
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    • 1999
  • Generally, When we measure of object 3D surfaces with phase shifting shadow moire method, it is use of optical system consist of light source, grating, and ccd camera. At this time, it is important parameter that vertical distance of grating and camera, grating and light source, and horizontal distance of camera and light source. When use camera consist of complex lens vertical distance of grating and camera is unknown parameter. From this cause equivalent wave length of moire fringe is uncertain. In this study, We exactly obtain a vertical distance of grating and camera so improve on measurement accuracy.

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Optical Performance Degradation Effects by Fabrication Errors of Circular-type Computer Generated Holograms

  • Kim, Young-Gwang;Rhee, Hyug-Gyo;Ghim, Young-Sik
    • Journal of the Korean Physical Society
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    • 제73권11호
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    • pp.1657-1662
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    • 2018
  • A null test method which relies on a computer generated hologram (CGH) is widely used to measure a large aspheric surface. For precise measurements of the surface shape of an aspheric optics, the CGH must precisely generate a wavefront that can fit on the ideal surface shape of the aspheric optics. If fabrication errors arise in the CGH, an unwanted wavefront will be generated and the measuring result will lack trustworthiness. Thus far, there has been limited research on wavefronts generated by CGH using only linear-type binary grating models. In this study, a theoretical error model of a circular-type zone plate, the most commonly used types for CGH patterns, is suggested. The proposed error model is checked by simulations and experiments.

광링식 3차원 형상 측정법에 관한 연구 (A Study on the Measurement of the 3-D Object Shapes by Using Optical Ring Method)

  • 강영준;박정환;김동우
    • 한국정밀공학회지
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    • 제13권9호
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    • pp.38-45
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    • 1996
  • The optical triangulation method has been used as a non-contact measuring method of three dimensional object whape. But this measuring method has narrow measuring range, non-linearity on steep slope surface and shadow effect. In this study, we discussed a new optical measurement method to overcome these kinds of demerits. The advantage of this new method is that it is possible to measure precisely the object shape having the steep slope surface without shadow effect. As exper- imental results, maximum displacement error was 200 .mu. m over the whole measuring when the incident angle on the object surface was within 60 degree.

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프레넬영역 안테나 측정법의 파리미터 분석과 측정 가이드라인 제시 (Parametric Analysis and Measurement Guideline of Fresnel Region Antenna Measurement Method)

  • 오순수
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2008년도 하계종합학술대회
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    • pp.351-352
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    • 2008
  • In this paper, parametric analysis of Fresnel region antenna measurement method has been performed for the square aperture having the uniformly distributed current. The optimum number of Fresnel region field and the tolerable distance between two antennas have been guided. This parametric analysis could be fully utilized when performing Fresnel region antenna measurement method. Other types of current distribution and aperture shape will be investigated in the near future

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인간공학적 좌석평가를 위한 좌면 형상 변형측정에 관한 연구 (A new seat surface deformation measurement method for ergonomic seat evaluation)

  • 이남식
    • 한국경영과학회:학술대회논문집
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    • 대한산업공학회/한국경영과학회 1990년도 춘계공동학술대회논문집; 한국과학기술원; 28 Apr. 1990
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    • pp.171-185
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    • 1990
  • In order to measure the shape deformation of seat surfaces, an indentation measurement mat was devised. The 50cm * 50 cm mat containing small polyethylene beads were made using two sheets of polyurethane film. The indentation measurement mat was shaped by vacuuming between the subject and the testing seat. This method showed less than 5mm of deformation measurement error. Deformation of CADILLAC and MAXIMA seats were compared to demonstrate usefulness of the new method.

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체형유형에 따른 의복의 착의 공간 형상 변화 (Out-line Space-shape Variation of Clothing Fitness with Somatotype)

  • 이수정
    • 한국가정과학회지
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    • 제1권2호
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    • pp.113-118
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    • 1998
  • Clothing shape is principally described in seven factors that are composed of clothing design, clothing material, clothing size, pattern design, sewing method and body motion etc.. The aims of this study was to measurement out-line space-shape variation of clothing fitness with somato type by using the image processing. The subjects for direct anthropometric measurements were 248 female college students aged from 19 to 22. The data were statistically analyzed by principal analysis and cluster analysis. The results were obtained three somato type. Also I made skirts in order to analyzed to the out-line space-shape variation of clothing fitness with body. The effect of somato type on the shape of flare skirts was determined by the out-line space-shape variation of clothing fitness with body. The out-line space-shape variation of clothing fitness with body was observed between the node number and amplitudes of clothing wave form and node number was determined at the maxim of space-shape amplitude, and the space-shape amplitudes have related with aspect ratio of cross-sectional shape. Results for flare skirts show changes in amplitude and mean with fabrics, somato type. therefore gray-level histogram are correlated with changes out-line space-shape, differences in drape spacing and related fabric properties and their somato type. (Korean J Human Ecology 1(2):113∼110 1998)

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