• Title/Summary/Keyword: Reliability of Measurement

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Measurement of 2-Dimensional Dopant Profiles by Electron Holography and Scanning Capacitance Microscopy Methods (일렉트론홀로그래피와 주사정전용량현미경 기술을 이용한 2차원 도펀트 프로파일의 측정)

  • Park, Kyoung-Woo;Shaislamov, Ulugbek;Hyun, Moon Seop;Yoo, Jung Ho;Yang, Jun-Mo;Yoon, Soon-Gil
    • Korean Journal of Metals and Materials
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    • v.47 no.5
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    • pp.311-315
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    • 2009
  • 2-dimensional (2D) dopant profiling in semiconductor device was carried out by electron holography and scanning capacitance microscopy methods with the same multi-layered p-n junction sample. The dopant profiles obtained from two methods are in good agreement with each other. It demonstrates that reliability of dopant profile measurement can be increased through precise comparison of 2D profiles obtained from various techniques.

Validity and Reliability of Ultrasound Measurement of Knee Joint Space Width in Individuals With Knee Osteoarthritis

  • Kim, Geon;Cha, Young-joo;Shin, Ji-won;You, Sung-hyun
    • Physical Therapy Korea
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    • v.26 no.1
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    • pp.60-66
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    • 2019
  • Background: Knee osteoarthritis (OA) is a single most arthritic disease. Knee joint space width (JSW) is commonly used for grading severity of knee OA. However, previous studies did not established criterion validity and test-retest reliability of ultrasound (US) image for measuring JSW. Objects: The aim of this study was to establish criterion validity and test-retest reliability of US measurement of medial and lateral knee JSW. Methods: Twenty-nine subjects with knee OA were participated. The US and X-ray were used to measure knee JSW. One sample Kolmogorov-Smirnov test was used to confirm the data normal distribution. Pearson correlation coefficient and ICC were used to calculated and establish criterion validity and test-retest reliability, respectively. Results: US measurement of medial and lateral knee JSW was highly correlated with radiographic imaging measure (r=.714 and .704, respectively). Test-retest reliabilities of medial and lateral knee JSW were excellent correlated (ICC=.959 for medial side and .988 for lateral side, respectively). Conclusion: US may be valid tool to measure knee JSW.

Reliability Prediction using Telcordia SR-332 in Electric Home Appliance (Telcordia SR-332를 이용한 가전제품 신뢰도 예측)

  • Lee Duck-Kyu
    • Journal of Applied Reliability
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    • v.5 no.4
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    • pp.427-438
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    • 2005
  • This paper is concerned with the problem in predicting the reliability of an LCD product, Product reliability calculation methods classify accelerated life test (ALT) and using the reliability standard as MIL-HDBK-217F and Telcordia SR-332. The reliability standard can calculate estimating value more quickly than accelerated life test. The system MTBF was calculated in accordance of Telcordia SR-332 standard which includes directions of part electronic measurement, temperature rise and environmental test data. This research is intended to obtain the useful information for each electric design step to save time and cost.

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The Software Reliability Growth Model base on Software Error Data (소프트웨어 오류 데이터를 기반으로 한 소프트웨어 신뢰성 성장 모델 제안)

  • Jung, Hye-Jung;Han, Gun-Hee
    • Journal of the Korea Convergence Society
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    • v.10 no.3
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    • pp.59-65
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    • 2019
  • In this paper, we propose a software quality measurement metrics of ISO / IEC 25023, which is newly proposed for software quality evaluation, to compare the difference with ISO / IEC 9126-2 which was used for software quality evaluation. In this paper, we propose a method for evaluating the quality of reliability based on the software reliability growth model among the eight quality characteristics presented in ISO / IEC 25023. Based on ISO / IEC 25023, software-quality evaluations demonstrate that there is some risk in evaluating reliability when based on data.

Clinical Usefulness of pH Papers in the Measurement of Salivary pH

  • Song, Chan-Woo;Kim, Hye-Kyoung;Kim, Mee-Eun
    • Journal of Oral Medicine and Pain
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    • v.40 no.3
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    • pp.124-129
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    • 2015
  • Purpose: Salivary pH is an easily measurable biochemical marker and related to various intraoral and systemic conditions. The aim of this study was to evaluate the reliability of the salivary pH measurement using pH paper. In addition, the normal values of salivary pH using pH paper were compared to those of pH meter to investigate the validity. Methods: Twenty healthy male participants attended this study (mean age, $24.5{\pm}1.47$ years). Unstimulated saliva and stimulated saliva were collected from each subject two times with the interval of a day and salivary pH was immediately measured by the two experienced examiners using pH paper and pH meter. The salivary pH was compared between the groups and inter- and intra-examiner reliability of pH paper was investigated. The intraclass correlation coefficient (ICC) was used to calculate variations. Results: All measurements had good to excellent inter-examiner (ICC 0.755 for unstimulated; 0.760 for stimulated saliva), intra-examiner (ICC 0.635 for unstimulated; 0.592 for stimulated saliva) reliability and two measurement methods using pH paper and pH paper also showed high reliability (ICC 0.852 for unstimulated; 0.640 for stimulated saliva). The values measured by pH paper were significantly lower than those measured by pH meter. Conclusions: pH paper showed adequate inter- and intra-examiner reliability and it presented the validity in terms of comparison with the pH meter as a standard in the salivary pH measurement.

Reliability study of the Pectoralis Minor Muscle Thickness Measurement using Rehabilitative Ultrasound Imaging

  • Lim, Ji Young;Lee, Se-Yeong;Jung, Seung-Hwa;Park, Dae-Sung
    • Journal of the Korean Society of Physical Medicine
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    • v.16 no.2
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    • pp.45-52
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    • 2021
  • PURPOSE: This study examined the imaging procedure of pectoralis minor muscle thickness and assessed the intra- and inter-rater reliability of the muscle thickness measured by two raters using rehabilitative ultrasound imaging (RUSI) in healthy individuals. METHODS: Fifteen participants (aged 21 - 28, seven females, and eight males) were involved in the study. The primary rater palpated the coracoid process and the fourth rib, defined as the width of the index finger lateral to the sternum to avoid breast tissues, and lined the two landmarks. The second examiner checked 1 / 3 (1st point) and 1 / 2 (2nd point) of the line length as measurement points. The two raters obtained right side muscle images of the participants at a standardized sitting position using RUSI with a 7.5 MHz linear transducer at 40mm depth. For intra-rater reliability, the principal rater took three images per point and tried to take one more with an interval. For the inter-rater reliability, the other rater performed the same tasks as the principal rater on the same day. The reliability was analyzed using the intra-class correlation coefficient (ICC), the standard error of the measurement (SEM), and Bland and Altman plots. RESULTS: The reliability at all points was excellent for the same rater (ICC3,1 = .973 - .978, SEM = .042 - .046), and between raters (ICC2,1 = .939 - .959, SEM = .059 - .097). CONCLUSION: These findings show that the RUSI could be reliable for examining the pectoralis minor muscle thickness in healthy individuals at all measurement sites.

Comparison of the Poor Insulator Detecting Technique for the Reliability Enhancement of the Electric Power Facilities (전력설비의 신뢰성 향상을 위한 불량애자검출기법의 비교)

  • Jung, Soon-Won;Koo, Kyung-Wan
    • The Transactions of the Korean Institute of Electrical Engineers P
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    • v.57 no.4
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    • pp.417-423
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    • 2008
  • For the evaluation in the safety of outdoor insulator, there are various methods such as: visual observation; voltage measurement; use of ultrasonic wave due to partial discharge; electric field measurement; use of infrared/ultraviolet sensor-type camera. However, many problems have been issued regrading the reliability of the evaluation test and safety of testing operation. Accordingly, the present study has investigated and analyzed the characteristics and mechanisms of the insulator deterioration, in order to obtain an optimal method for detecting poor insulator so that the reliability of power facilities can be enhanced. Besides, based on theoretical analysis of domestic and international detection methods for poor insulator, the reliability has been compared and evaluated quantitatively. As a result, it was shown that the corona camera would be the best choice for domestic workplace application in detecting poor insulator for enhancing the reliability of power transmission line.

Turbo Positioning Using Link Reliability in Wireless Networks

  • Yun, Kyungsu;Park, Ji Kyu;Ahn, Jae Young;Kwon, Jae Kyun
    • ETRI Journal
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    • v.40 no.1
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    • pp.101-110
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    • 2018
  • In wireless positioning systems using range measurements non-line-of-sight (NLOS) links cause estimation errors. Several studies have attempted to improve the positioning performance by mitigating these NLOS errors. These studies, however, have focused on the performance of a dataset consisting of three or more links. Therefore, measurement errors induced by links are averaged, and a reliable link is not fully utilized in the dataset. This paper proposes a Link Reliability based on Range Measurement (LRRM) scheme, which specifies the relative reliability of each link using residuals. The link reliability becomes the input to a Link Residual Weighting (LRW) scheme, which is also proposed as a weighted positioning scheme. Moreover, LRRM and LRW constitute new turbo positioning, where the estimation errors are reduced considerably by iterative updates.

Case Study on the Compatibility of Measurement Systems with Part-to-part Variations in Automobile Industry

  • Lee, Myung-Duk;Lim, Ik-Sung;Sung, Chun-Ja
    • International Journal of Reliability and Applications
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    • v.9 no.1
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    • pp.17-30
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    • 2008
  • Analysis of measurement systems is important to determine if the measurement process is adequate to measure the part-to-part variability in the process. Control chart techniques provide an effective, and easy-to-use method for performing this analysis. However, application with the real data for the evaluation procedure for multiple measurement systems have not been demonstrated. This research will provide a methodology for the evaluation of part-to-part variation and variation of different measurement systems step by step followed by number of case studies for each methodologies provided.

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Development of Measurement of Stress for Female Marriage Immigrants in Korea (여성결혼이민자의 스트레스 측정도구 개발)

  • Park, Min Hee;Yang, Sook Ja
    • Journal of Korean Public Health Nursing
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    • v.26 no.3
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    • pp.518-531
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    • 2012
  • Purpose: This study was conducted in order to develop and test a measurement for assessment of stress of female marriage immigrants in Korea. Methods: Forty four preliminary items were initially developed based on literature review and focus group interviews. Those items were evaluated by experts for content validity, resulting in six factors and 26 items. The 26 items were translated into Chinese, Vietnamese, and English by professional translators and were reviewed by native speakers of each language who are fluent in Korean. For testing validity and reliability, data were collected from 323 female marriage immigrants residing in five regions in Korea. Results: As a result of item analysis, 25 items were selected. Factor analysis yielded 21 items in four factors, including 1) household economic 2) parenting and discrimination 3) cultural and 4) emotional stressors, explaining 61.3% of the total variance of stress of female marriage immigrants in Korea. The Cronbach's alpha reliability coefficient was .903 for the overall instrument and .692-.892 for four factors. Conclusion: Measurement of stress for female marriage immigrants in Korea has high validity and reliability. Therefore, this measurement may be utilized for systematic assessment of stress and for identification of areas of support for female marriage immigrants in Korea.