• Communications for Statistical Applications and Methods
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• 제29권5호
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• pp.533-545
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• 2022

Collection of data on several variables, especially in the field of medicine, results in the problem of measurement errors. The presence of such measurement errors may influence the outcomes or estimates of the parameter in the model. In classification scenario, the presence of measurement errors will affect the intrinsic cum summary measures of Receiver Operating Characteristic (ROC) curve. In the context of ROC curve, only a few researchers have attempted to study the problem of measurement errors in estimating the area under their respective ROC curves in the framework of univariate setup. In this paper, we work on the estimation of area under the multivariate ROC curve in the presence of measurement errors. The proposed work is supported with a real dataset and simulation studies. Results show that the proposed bias-corrected estimator helps in correcting the AUC with minimum bias and minimum mean square error.

• 대한화학회지
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• 제67권5호
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• pp.319-332
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• 2023

Guide to the Expression of Uncertainty in Measurement (GUM)가 발간된 1993년부터 측정불확도는 측정학의 핵심 개념으로 여겨져 왔으며 적절한 불확도 평가의 중요성은 꾸준히 높아지고 있다. 하지만 측정불확도의 개념과 GUM에 대해 충분히 정확하고 상세하게 설명하는 국문 자료는 거의 없는 실정이다. 본 총설은 측정불확도 개념과 GUM의 수학적, 역사적, 철학적 배경을 상세하게 설명하며 화학 분야 불확도 평가의 특수성을 논한다.

• Nuclear Engineering and Technology
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• 제55권8호
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• pp.3114-3120
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• 2023

A high-accuracy magnetic field measurement device based on a cyclotron is being developed for accelerator mass spectrometry (AMS). In this study, a magnetic field measurement device consisting of a Hall probe sensor, piezo-motor, and step motor was developed to measure the magnetic field of the AMS cyclotron magnet. The Hall probe sensor was calibrated to achieve positional accuracy by using polar coordinates. The measurement results between the ratchet gear and piezo-motor, which are the instruments used for driving the measurement device, were analyzed. The measurement result of the device with a piezo-motor exhibits a difference of 5 Gauss (0.04%) as compared with the simulation result.

• Current Optics and Photonics
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• 제7권4호
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• pp.378-386
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• 2023

A wideband instantaneous frequency measurement (IFM) system is been proposed, designed and analyzed. Phase modulation to intensity modulation conversion is implemented based on the stimulated Brillouin scattering (SBS) effect, and the microwave frequency can be measured by detecting the change in output power. Theoretical analysis shows that the frequency measurement range can be extended to 4f_b by adjusting the two sweeping signals of the phase modulators with a difference of 2f_b. The IFM system is set up using VPI transmission maker software and the performances are simulated and analyzed. The simulation results show that the measurement range is 0.5-45.96 GHz with a maximum measurement error of less than 9.9 MHz. The proposed IFM system has a wider measurement range than the existing SBS-based IFM system.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2001년도 춘계학술대회논문집E
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• pp.601-606
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• 2001

Measurement uncertainty should be evaluated according to ISO/IEC 17025. In Flow measurement area, uncertainty evaluation scheme was applied to the reference flow meter, sonic nozzle. Uncertainty was calculated by evaluating various uncertainty factors affected in flow measurement. The expanded uncertainty of the sonic nozzle was 0.21 % (confidence level of 95 %). This evaluation example will be useful in flow measurement uncertainty determination of other flow meters.

• 품질경영학회지
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• 제21권2호
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• pp.48-60
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• 1993

We have depended upon the quantitative analysis for productivity measurement. and excluded the qualitative analysis from productivity measurement. But I think that the qualitative analysis must be considered so as to get a effective productivity measurement This paper intened to establish improvement productivity measurement adopted quality cost of all the qualitative elements.

• 대한전기학회논문지:시스템및제어부문D
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• 제51권3호
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• pp.96-99
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• 2002

We developed 1:1 resistance ratio measurement system for precision measurement of a series-resistor type dc voltage divider. By using active guard technique and exchange technique, any leakage effects, which are one of the most critical error sources, were successfully removed. The best measurement uncertainty with the developed ratio measurement system was estimated to be approximately $10^{-8}\;for\;10\;k{\Omega}\;and\;100\;k{\Omega}$.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2004년도 춘계학술대회 논문집
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• pp.219-223
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• 2004

Korea Railroad Research Institute(KRRI) propelled sensing and measurement techniques development for measure of Lateral Force and Vertical Force With Italy to international cooperation research project for laser technology for measurement of wheel/rail interaction force. In this paper, we compared the laser technology for measurement of wheel/rail interaction force with the existing method. And then, we suggests interaction force measurement system procedure of hereafter.

• 대한인간공학회:학술대회논문집
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• 대한인간공학회 1997년도 춘계학술대회논문집
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• pp.247-255
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• 1997

In this study, the comparison of the basic human body measurement definitions and anthropometric terms between the Korean Standard and the International Standard. Measurement definitions, measurement method and measurement terms of the international standard ISO 8559, 7250 were compard with the KSRI-88-103-IR. We have tried to suggest the new methods and new terms such as eye height, waist height, arm length.

• 대한가정학회지
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• 제27권2호
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• pp.43-52
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• 1989

This study deals with the standardization of anthropometric terms related to body measurement points and lines that are to be the basis in body measurement. It investigates the state-of-the art of anthropometric terms used among middle and high schools, universities, dressmaking schools, and experts and set up the directions of standardization. According to the directions, 39 body measurement points and 9 body measurement lines were studied and a draft standards on anthropometric terms was suggested.