• 제목/요약/키워드: Uncertainty measurement

검색결과 930건 처리시간 0.03초

유체-구조 연동운동 3차원 측정시스템의 성능 검증 (Performance Tests on the 3D-Flow-Structure-Interactions-Measurement System(FSIMS))

  • 도덕희;조효제;백태실;황태규
    • Journal of Advanced Marine Engineering and Technology
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    • 제33권1호
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    • pp.81-89
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    • 2009
  • Performance tests on the 3-Dimensional Flow-Structure-Interactions-Measurement System(FSIMS) have been carried out. Experimental data obtained by the FSIMS on a floating cylinder have been used to generate a set of artificial images. Comparisons between the data obtained by the use of the artificial images and those original experimental data have been made. Another set of artificial images have also been generated based on theoretically modulated sinusoidal motions, and comparisons between the data obtained by the use of these artificial images and the theoretical ones have been carried out. It has been verified that the FSIMS has a measurement uncertainty of 0.04-0.06mm/frame for velocity vectors and 0.002-0.01mm for the cylinder's positions.

초음파 변환기의 감도 교정 시스템 구성 (Design of the Calibration System for Determining the Sensitivity of Ultrasonic Transducer)

  • 사공성대;조문재;최봉열
    • 제어로봇시스템학회논문지
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    • 제5권2호
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    • pp.200-207
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    • 1999
  • In this paper, a precise sensitivity measurement system of ultrasonic transducer in the frequency range from 1 MHz to 15 MHz, which can implement the reciprocity principle is constructed. All of the elements of this system such as the ultrasonic preamplifier, ultrasonic absorber, water tank, water degassing system, and four-axes translator and reflector are constructed. For the performance evaluation of the calibration system, a standard hydrophone precisely calibrated from PTB(Physikalisch Technische Bundesanstalt) in Germany are used. And the system parameters which affected the evaluation of the measurement accuracy and the reproducibility in various measuring conditions are considered. The measurement uncertainty of the calibration system is estimated within $\pm$ 2.0㏈.

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정전용량센서를 이용한 대구경 비구면 형상의 기상측정에 관한 연구 (A Study on the On-machine Profile Measurement of Large Aspheric Form using Capasitive Sensor)

  • 김건희;원종호
    • 한국기계가공학회지
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    • 제2권3호
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    • pp.56-61
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    • 2003
  • This paper described about on-machine profile measurement of aspheric surfaces using contact probing technique in ultra precision machine. A contact probe has been designed as a sensing device to obtain measuring resolutions in nanometer regime using a circle leaf spring mechanism and a capacitive-type sensor. The contact probe which is installed on the z-axis is In touch with the aspheric objects which is fixed on the spindle of the diamond turning machine(DTM) during the measuring procedure. The x, z-axis motions of the machine are monitored by a set of two orthogonal plane mirror type laser interferometers. As a results, the developed contact probe on-machine measurement system showed 10 nanometers repeatability with a ${\pm}2{\sigma}$ and uncertainty of 200 nmPv.

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비구면 초정밀절삭 공정기술에 관한 연구 (A study on Ultra Precision machining process for Aspheric)

  • 김건희;홍권희;김효식;김현배;양순철;윈종호
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 2003년도 춘계학술대회 논문집
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    • pp.90-93
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    • 2003
  • This paper described about the ultra-precision profile measurement of aspheric surfaces using contact probing technique. A contact probe has been designed as a sensing device to obtain measuring resolutions in nanometer regime utilizing a circle leaf spring mechanism and a capacitive-type sensor. The, contact probe is attached on the z-axis during measurement while aspheric object are supported on the diamond turning machine(DTM). The machine xz-axis motions are monitored by a set of two orthogonal plane mirror type laser interferometers. Experimental results show that the contact probing technique developed of on-machine measurement system in this investigation is capable of providing a repeatability of 10 nanometers with a $\pm$20 uncertainty of 200nmPv.

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비구면 렌즈의 형상 측정을 위한 접촉식 프로브 기술 개발 (Contact Probing Technique for Profile Measurement of Aspheric Lenses)

  • 유승봉;장인철;김승우
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 2000년도 춘계학술대회 논문집
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    • pp.603-606
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    • 2000
  • This dissertation is concerned with ultra-precision profile measurement of aspheric surfaces using contact probing technique. A contact probe has been designed as a sensing device to obtain measuring resolutions in nanometer regime utilizing a leaf spring mechanism and a capacitive-type sensor. The contact probe is attached on the z-axis during measurement while aspheric objects are supported on an precision xy-stage whose lateral motions are monitored by a set of two orthogonal plane mirror type laser interferometers. Experimental results show that the contact probing technique developed in this investigation is capable of providing a repeatability of 50 nanometers with a $\pm$3$\sigma$ uncertainty of 300 nanometers. Thermal disturbance is found the most significant factor that should be precisely controlled for accurate measurement.

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전원단자 방해파 전력측정의 불확실성 개선

  • 신국선;최성호;김남;박성욱
    • 한국전자파학회지:전자파기술
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    • 제14권1호
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    • pp.81-88
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    • 2003
  • CISPR has published the limits on the noises emitting from power lines and signal lines. But different measurement environment and measurement methods are used in every countries. This difference causes much confusion in understanding the results measured by different test laboratories. In this paper, we measure EMI noise using the absorbing clamp method that takes short measurement time and is described in CISPR 13, 14-1, 16-2. We analyze the cause of the difference of measurement results and propose the method for improving the uncertainty

The Phase-sensitivity of a Mach-Zehnder Interferometer for Coherent Light

  • Shin, Jong-Tae;Kim, Heo-Noh;Park, Goo-Dong;Kim, Tae-Soo
    • Journal of the Optical Society of Korea
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    • 제3권1호
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    • pp.1-9
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    • 1999
  • We have studied the sensitivity of four different phase shift measurement schemes with a Mach-Zehnder interferometer. The input light is considered to be in a coherent state and the detectors are assumed to be ideal with the quantum efficiency of unity. It is shown by direct calculation of the operators corresponding to the measurement schemes that the uncertainty of the phase-shift measurement is limited to the classical one $\frac{1}{\sqrt{m}}$(m is the average number of the photons in the input state) regardless of the phase-shift measurement schemes.