• 제목/요약/키워드: standard calibration

검색결과 1,146건 처리시간 0.035초

가역원리에 의한 1인치 표준 컨덴서 마이크로폰의 정밀교정 (Precision Calibration of 1-Inch Standard Condenser Microphone by Reciprocity Technique)

  • 서상준;조문재
    • 한국음향학회지
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    • 제8권5호
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    • pp.23-32
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    • 1989
  • 표준 컨덴서 마이크로폰의 정밀 교정은 가역원리를 이용한 가역교정에 의해 이루어진다. 본 연구에서는 가역교정 중에서도 결합기를 이용하는 음압교정(pressure calibration)을 수행하여 세 개의 1인치 컨덴서 마이크로폰의 음압감도를 결정하였다. 마이크로본의 음압감도를 정밀하게 결정하기 위해서는 전압이나 결합기의 치수를 정밀하게 측정하여야 하며 결합기의 구조상 발생하는 제반 현상들에 대한 보정을 정확하게 해 주어야 한다. 이와같은 사항들을 정화하게 고려할 경우 가역교정에 의한 교정정밀도는 저주파와 중간 주파수 영역에서 0.05dB이며 10kHz 이상에서는 0.ldB가 된다.

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불확도 요인 분석을 통한 교정 시스템 적합성 평가 및 시험기준 결정 방안 (Calibration System Suitability Evaluation and Test Limits Determination Method through Factor Analysis of Uncertainty)

  • 김홍탁;김부일
    • 한국전자통신학회논문지
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    • 제14권6호
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    • pp.1139-1144
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    • 2019
  • 정밀측정장비의 성능을 진단 및 확인하는 교정 시스템은 교정결과의 신뢰성 확보를 위해 국제규격의 요구조건을 준수함으로 교정결과의 오판정 위험을 최소화하고 있다. 본 논문에서는 교정기관에서 고성능의 장비를 획득 및 운영하기에 불가능한 경우 불확도 요인 분석을 통한 교정 시스템 적합성 평가 방안과 가드밴드 기법을 이용하여 성능기준을 대체하는 최적화된 시험기준 산출모형을 제안한다. 제안된 방법은 교정 시스템의 정량적인 평가기준과 국제규격에서 요구되는 허위수락위험 확률 기준을 충족을 위한 최적화된 시험기준을 제공한다.

근적외 분광분석법을 이용한 버어리종 잎담배 화학성분 분석

  • 김용옥;장기철;이경구
    • 한국연초학회지
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    • 제21권1호
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    • pp.95-101
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    • 1999
  • This study was carried out to analyze chemical components in burley tobacco using near infrared spectroscopy(NIRS). Samples were collected in '96 and '97 crop year. Calibration equations were developed by modified partial least square. The standard error performance(SEP) of '96 crop year samples between NIRS and standard laboratory analysis were 0.25% for nicotine, 0.18% for total nitrogen, 0.59% for crude ash, 0.32% for ether extracts, and 0.14% for chlorine, respectively. The analytical results of '97 crop year samples were similar to those of '96 crop year samples. The analytical result of '97 crop year samples analyzed by '96 calibration equation was more inaccurate than that of '96 crop year samples. The SEP of '96 or '97 crop year samples applying calibration equation derived from '96 plus '97 crop year samples was similar to that of '96 or '97 crop year samples analyzed by '96 or '97 calibration equation, respectively. The SEP of '97 crop year samples analyzed by calibration equation derived from '96 plus '97 crop year samples was more accurate than that of '97 crop year samples analyzed by '96 calibration equation. To improve the analytical inaccuracy caused by the difference of crop year between calibration and prediction samples, we need to include the prediction sample spectra which were different from calibration sample spectra in recalibration sample spectra, and then develop recalibration equation. The NIRS can apply to analyze burley leaf tobacco, leaf process or tobacco manufacturing process which were required the rapid analytical result.

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스피닝 로터 게이지 교정 불확도 (Calibration uncertainty of a spinning rotor gauge)

  • 홍승수;임인태;신용현;정광화
    • 한국진공학회지
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    • 제12권1호
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    • pp.7-15
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    • 2003
  • 스피닝 로터 게이지는 표준기관의 고진공 국제비교에 전달표준기로 상용되고 있으며, 고진공 국가표준기인 동적교정장치를 이용하여 스피닝 로터 게이지를 교정하였다. 교정 결과의 불확도를 국제표준화기구에서 권고한 A형 불확도, B형 불확도, 합성표준불확도, 확장불확도 등으로 구분하여 평가하는 방법을 제시하였다. 이 방법에 따라 평가한 스피닝 로터 게이지의 합성표준불확도는 $1.8007\times10^{-5}$ Pa ~$4.8422\times10^{-5}$ Pa 이었다.

국가교정검사기관의 전자파전력 측정정확도의 분석 및 평가 (Analysis and Evaluation of the Accuracy of Electromagnetic Power Measurement at National Calibration and Test Organizations)

  • 강태원;강웅택;박병권
    • 전자공학회논문지A
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    • 제32A권1호
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    • pp.53-60
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    • 1995
  • The aims of this study are to evaluate the measurement capability of the electromagnetic power and to understand the current state of standard maintanance of the eight participants among the thirteen national calibration and test organizations. The calibration factors were measured at six test frequencies, 50, 100, 500, 1000, 5000, 10000 MHz by organizations and KRISS on the basis of round robin test. The results were analyzed by calculating the standard deviation of the measured values from the standard values. The analysis shows good agreement within 1.0% for all participants at the measurement frequencies. Therefore, the measurement capability of all participants is good in the frequency range of 50 MHz to 10 GHz. For the four participants which specified standard deviations of repeated measurements in their reporst, the total uncertainties is less than 1.9% at the measurement frequencies.

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직류 저주파 분야 인터넷 원격교정시스템의 개발과 활용 (Development and Application of Internet Remote Calibration System in the field of DC and LF)

  • 정재갑;김규태;박승남;송양섭
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2003년도 하계학술대회 논문집 D
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    • pp.2020-2021
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    • 2003
  • Korea Research Institute of Standards and Science (KRISS) has developed a Web-based, remote, Internet calibration system to calibrate the Fluke 5700A/5720A calibrator using a transportable standard: specifically, multifunction transfer standard 4950. Although the uncertainty for the Internet calibration is up to two times larger than that using conventional manual calibration, it has many advantages: no need to transport the customer equipment, a reduction in the calibration service time, a directly enforced traceability to the national standards, convenience, and ease of use for the customers.

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단층촬영영상을 이용한 T.O.D Calibration의 정확성과 유용성에 관한 비교연구 (Comparative Study on Accuracy and Usefulness of Calibration Using CT T.O.D)

  • 서정범;김동현;이정범
    • 대한디지털의료영상학회논문지
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    • 제13권1호
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    • pp.39-48
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    • 2011
  • Uses a Tomographic scan image and Table Object Distance(TOD) price after measuring, uses accuracy and usability of blood vessel diameter(Vessel Diameter) measurement under comparison evaluating boil TOD Calibration. The patient who enforces Prosecuting Attorney abdomen Tomographic scan in the object the superior mesentery artery uses PACS View from abdomen fault image and from blood vessel diameter and the table measures the height until of the blood vessel. Uses Angio Catheter from Angiography(5 Fr.) and enforces is measured from PACS View the height until of the table which and the blood vessel at TOD Calibration price and the size of the superior mesentery artery inputs measures an superior mesentery artery building skill. Catheter Calibration input Agnio Catheter where uses in Angiography the size of the superior mesentery artery at Catheter Calibration price and they measure. Produced an accuracy from monitoring data and comparison evaluated. The statistical program used SPSS. TOD Calibration accuracy was 96.53%, standard deviation is 0.03829. Catheter Calibration accuracy of 92.91%, standard deviation is 0.05085. Represents a statistically significant difference(p = 0). According to age and gender was not statistically significant(p > 0.05). TOD Calibration correlation coefficient R-squared of 88.8%, Catheter Calibration of the R-squared is 75.5%. High accuracy of both methods. Through this study, CT images using the measured distance between the table and the Object, TOD Calibration accuracy higher than two Catheter Calibration was measured. TOD and Catheter Calibration represents a statistically significant difference(p = 0).

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In-Process Relative Robot WorkCell Calibration

  • Wang, Jianjun;Sun, Yunquan;Gan, zhongxue
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 2003년도 ICCAS
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    • pp.269-272
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    • 2003
  • Industry is now seeing a dramatic increase in robot simulation and off-line programming. In order to use off-line programming effectively, the simulated workcell has to be identical to the real workcell. This requires an efficient and accurate method for the workcell calibration. Currently used techniques in the industry, however, are typically time-consuming, expensive and therefore not suitable for in-process application. This is because most of these techniques are based on the so-called “absolute calibration” method. In contrast to absolute method, relative calibration only measures the difference of an interested object relative to a standard reference. Owing to the small measurement range requirement, relative calibration method is very cheap and can achieve very high accuracy. In this paper the relative method is applied to calibrate an entire grinding workcell. Linear gauge is the only measurement device used. This workcell calibration includes tool center point (TCP) calibration and work object frame calibration. Due to the efficiency of the calibration algorithm and the simplicity of the calibration setup, the described calibration procedure can be done in process.

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토양 중금속 함량 측정에 대한 토양오염공정시험기준과 국제표준간의 적합성 평가 (Assessment for the Comparability between Korean Ministry of Environment Standard and ISO Standard for the Determination of Heavy Metals in Soil)

  • 신건환;이군택;이원석;김지인;김보경;박현정
    • 한국지하수토양환경학회지:지하수토양환경
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    • 제17권3호
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    • pp.1-9
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    • 2012
  • According to the agreement on WTO/TBT, we are under the situation to adopt international standard (ISO standard) as a national standard if it exists. However, in case of environmental area, it is a domestic legal obligation to use Korean environmental standard method(KESM) for analyzing various contaminants. Therefore it is necessary to assess the comparability between KEM and ISO standard prior to apply ISO standard to soil conservation law in Korea. The main purpose of this study is to assess the comparability of both methods for analyzing heavy metals in soil. We looked over various aspects like pre-treatment, calibration curve range, detection wavelength, soil organic matter content and so on. Apparently, the procedure of both methods is almost same. However in details, both methods are different in stationary time before aqua-regia extraction using reflux system, calibration curve range for Cu, Pb, Ni and measuring wavelength for Pb. According to the results of comparison test, the results were significantly different when the different calibration range was used. In case that all the extracts independent of methods were reanalyzed with the same calibration range of each method, both methods showed statistically same results. Other conditions like different stationary time, measuring wavelength of AAS and soil organic matter content did not have any influence on the analytical result. Therefore, we suggest to extend the calibration curve range to 0~8 mg/L which is used in KS I ISO standard(Korean standard related with environment which is translation version of ISO standard without any technical change). In case of $Cr^{6+}$, the results showed no significant differences between two methods even though the pretreatment, instrumentation and other analysis conditions were different. In addition to UV/Visble spectrometry of KESM for soil contamination, we suggest to adopt ion chromatography of ISO 15192(US EPA method 7199) for analyzing $Cr^{6+}$ with the consideration of laboratory work efficiency.

온도교정기 RTD 저항 및 열전대 직류전압 교정기법 연구 (A Study on the Calibration Technique of RTD and Thermocouple System)

  • 오광석;이왕헌
    • 전기전자학회논문지
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    • 제20권4호
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    • pp.439-448
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    • 2016
  • 온도 측정을 위해 RTD와 열전대 센서가 산업이나 연구 분야에 널리 사용되고 있다. RTD 및 열전대의 온도 교정기에 대한 표준교정절차는 측정에서 포함되는 불확도의 교정 결과를 나타내는 방법을 보여준다. 지금까지 이들에 대한 표준교정절차가 확립되지 않아 다소의 불편함과 표준교정 업무에 어려움이 있었다. 이러한 문제를 해결하기 위해 온도 교정기의 RTD 및 열전대에 대한 교정기법을 연구하게 되었다. 본 논문에서는 이들에 대한 수학적 모델과 교정결과 자료를 제시하였다.