• 제목/요약/키워드: Measurement standards

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1 GHz 대역 임펄스의 스펙트럼 진폭 불확도 평가 (Uncertainty Analysis of 1 GHz Band Impulse Spectrum Amplitude)

  • 이동준;이주광;권재용;강태원
    • 한국전자파학회논문지
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    • 제23권12호
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    • pp.1365-1372
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    • 2012
  • 본 논문에서는 임펄스 발생기로부터 계측 시스템으로 전달되는 펄스 신호의 주파수 성분을 매우 정밀하게 측정하고 관련 불확도를 평가하는 시스템과 방법을 다루었다. 임펄스 신호의 스펙트럼 진폭 불확도를 결정짓는 복잡한 요소들과 그 해석적 분석 방법 및 실측을 통한 평가 결과를 제시하였다. 측정 시스템의 확장 불확도는 0.015이고, 이는 국내 최고 수준이며 세계적 교정기관의 결과와도 대등한 수준이다.

전기마이크로미터를 이용한 정밀측정용 정반의 평면도 측정에 관한 연구 (A Study on the utilization of electronic micrometer for flatness measurement of precision surface plate)

  • 김구영;우인훈;임재선;정명세;김종억
    • 한국정밀공학회지
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    • 제4권3호
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    • pp.52-59
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    • 1987
  • The flatness of a precision surface plate is generally measured by using precision angular measuring instruments such as laser interferometers, autocollimators and electronic levels. Since these instruments are expensive and measurement procedures are complex, such methods are not widely used in industries. In this study, an electronic micrometer that is easy to use and inexpensive to produce was developed in order to solve this problem. The flatness of a black granite surface plate, measured using this device was compared with the values obtained by using the conventional three methods. The results were consistent within ${\pm}1{\mu}m$. It proves that the flatness measuring method using electronic micrometers can be utilized for quantitative measurement. An accessory device that can improve the precision of measurement by attaching to the electronic micrometer was also designed and fabricated.

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어린이 놀이터 놀이시설의 안전도에 관한 조사 (An Actual Measurement on Safety of Play Equipments in the Outdoor Playground)

  • 석주영;안옥희;박인전
    • 한국주거학회논문집
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    • 제13권2호
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    • pp.47-53
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    • 2002
  • The purposes of this study actually measure to the dimension and the quality of material play equipment's examine whether they meet safety standards or not, and intend to offer basic data to present proper safety standards concerning the dimension of play equipment in the end. The subjects for this study were 59 outdoor playgrounds, 30 among them located in apartment sites and the remainder did in residential districts. The time of actual measurement was in June 1999, and June 2000. Data were analyzed into frequency, percentage, mean, and standard deviation by using SPSSWIN program. The main results were as follows.: First, more than half of playgrounds were assessed for being traffic hazards due to the adjacent streets. And they were hardly equipped with the toilet and drinking water facilities, but were almost equipped with the shade of a tree and benches. Second, it was caused in inconvenience of children's use and difficulty of play equipments'management, since the quality of play equipments materials was consisted of wood or metal. Third, the standards for swing and slide were established in detail and actual measurement's results were suitable to standards'value as well, whereas the standards for seesaw and climber were not in detail and they did not design or install suitably.

표준구직경 정밀측정 간섭계 제작 (Construction of Precision Measurement Interferometer for Standard Ball Diameter)

  • 장경호;이용재;서호성;도진열;강시홍
    • 센서학회지
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    • 제8권4호
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    • pp.347-353
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    • 1999
  • 구직경의 정밀측정을 위한 간섭계를 제작하고 직경이 78 mm인 철제구를 측정하였다. 제작된 간섭계는 두 평행판 사이에 구를 설치할 수 있도록 제작된 에탈론을 단일변형체의 평행이동판 위에 설치하고 구의 양면과 에탈론의 두 반사면 사이에서 생성되는 두 간섭신호의 위상차로부터 구 직경을 측정할 수 있도록 하였다. 위상차는 광검출기로 감지된 한 쌍의 간섭무늬신호에 대한 상관계수로부터 계산하였다. 측정결과 철제구의 직경은 78.1893544 mm였으며, 측정불확도는 95.5%의 신뢰수준에서 29 nm로 나타났다.

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고경사 자유곡면 측정을 위한 파장변조 층밀리기 간섭계 (Wavelength Scanning Lateral Shearing Interferometer for Freeform Surface Measurement)

  • 이혁교;김영식;이주형;양호순;이윤우
    • 한국정밀공학회지
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    • 제31권3호
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    • pp.199-205
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    • 2014
  • We propose a new variant of lateral shearing interferometer with a tunable laser source that enables 3D surface profile measurements of freeform optics with high speed, high vertical resolution, large departure, and large field-of-view. We have verified the proposed technique by comparing our measurement result with that of an existing technique and measuring a representative sample of freeform optics. Moreover, we propose a new algorithm that is able to compensate the rotational inaccuracy.

집속초음파 자극기의 성능평가를 위한 팬텀 내부온도 측정 (Measurement of Internal Temperature Distribution for the Evaluation of Focused Ultrasound (FUS) Stimulation Devices)

  • 도일;조주형;김성목;백경민;김용태;박승민
    • 대한의용생체공학회:의공학회지
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    • 제43권3호
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    • pp.147-152
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    • 2022
  • This research is to measure real-time temperature distribution inside a tissue-mimicking phantom for the safety and effectiveness evaluations of focused ultrasound (FUS) device capable of linear scanning stimulation. Since the focusing area of the FUS stimulation device is smaller than diameter of conventional thermal probe and keeps moving, it is impossible to monitor temperature distribution inside the phantom. By using the phantom with a thin film temperature sensor array inserted, real-time temperature change caused by the FUS device was measured. The translation of the measured temperature peak was also tracked successfully. The present phantom had been experimentally proven to be applicable to validate the performance and safety of the therapeutic ultrasound devices.

광원 및 디스플레이 기기의 색특성 측정의 불확도 평가 (Uncertainty Evaluation of Color Measurement on Light Sources and Display Devices)

  • 박성종;이동훈;김용완;박승남
    • 한국광학회지
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    • 제20권2호
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    • pp.110-117
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    • 2009
  • 본 논문은 광원 및 디스플레이 기기의 중요한 품질 지표 중 하나인 색특성 측정과 관련하여 대표적인 측정량인 CIE 1931(x, y) 색좌표, CIE 1960(u, v) 색좌표, 상관색온도(correlated color temperature, CCT), 분포온도(distribution temperature)에 대한 측정불확도 평가방법과 그 산출 예를 소개한다. 분광복사계를 사용하여 광원의 상대분광분포를 측정하고 이로부터 위의 색특성 측정량을 계산하는 경우에 대하여 표준소급체계를 소개하고, 상대분광분포의 불확도가 각 색특성 측정량의 불확도로 전파되는 과정을 파장간 상관관계를 고려한 행렬식을 이용하여 일관되게 유도한 후, CIE A 표준광원, LED 백색광, LCD 백색광에 대해 측정불확도 산출 예를 보였다.