• Child Health Nursing Research
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• 제18권2호
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• pp.76-84
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• 2012

Purpose: This study was done to develop a cell phone addiction scale for Korean children. Methods: The process included construction of a conceptual framework, generation of initial items, verification of content validity, selection of secondary items, preliminary study, and extraction of final items. The participants were 268 children from grades 4 to 6 in two urban elementary schools. Construct validity, internal consistence reliability, and split-half reliability were used to analyze the data. Results: Nine items were categorized into 2 factors explaining 61.29% of total variance. The factors were labeled as obsessive compulsion (6 items) and dependency (3 items). Cronbach's alpha coefficient for the 9 items was .87, and Spearman-Brown coefficient was .83. Scale scores identified children as high risk users, at risk users, or average users by standard scores. Conclusion: The above findings indicate that the cell phone addiction scale for children has good validity and reliability when used with Korean children.

• Nuclear Engineering and Technology
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• 제45권2호
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• pp.165-178
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• 2013

A comprehensive review on the technical standards about human factors (HF) design and software reliability maintenance for digital instrumentation and control (I&C) and human-machine interface technology (HMIT) in Japanese light water reactor nuclear power plants (NPPs) was given in this paper mainly by introducing the relevant activities at the Japan Electric Association to set up many industrial standards within the traditional framework of nuclear safety regulation in Japan. In Japan, the Fukushima Daiichi accident that occurred on March 11, 2011 has great impact on nuclear regulation and nuclear industries where concerns by the general public about safety have heightened significantly. However for the part of HF design and software reliability maintenance of digital I&C and HMIT for NPP, the author believes that the past practice of Japanese activities with the related technical standards can be successfully inherited in the future, by reinforcing the technical preparedness for the prevention and mitigation against any types of severe accident occurrence.

• 조명전기설비학회논문지
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• 제22권9호
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• pp.75-81
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• 2008

최근 IEC61850이 변전소자동화시스템의 국제표준으로 자리 잡고 있는데, 그 중에서도 보호IED의 신뢰도는 매우 중요하다. 본 논문에서는 IEC61850의 특징을 이용하여 보호IED의 신뢰도를 향상시키는 새로운 방법을 제시한다. 본 논문에서 제시하는 신뢰도 향상기법은 적은 수의 백업 IED를 사용하므로 경제적이면서도, 기존의 2계열화나 백업보호방식에 비하여 오부동작을 현저히 감소시킬 수 있다. 6모선 예제계통에 대한 모의실험을 통하여 본 논문에서 제시하는 신뢰도 향상기법의 유용성을 검증하였다.

• Geomechanics and Engineering
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• 제17권6호
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• pp.597-606
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• 2019

Ultrasonic Time-of-Flight Diffraction (TOFD) techniques are useful methods for non-destructive evaluation of fracture characteristics. This study focuses on the reliability and accuracy of ultrasonic diffraction methods to estimate the depth of rock fractures. The study material includes three different rock types; andesite, basalt and ignimbrite. Four different ultrasonic techniques were performed on these intact rocks. Artificial near-surface fracture depths were created in the laboratory by sawing. The reliability and accuracy of each technique was assessed by comparison of the repeated measurements at different path lengths along the rock surface. The standard error associated with the predictive equations is very small and their reliability and accuracy seem to be high enough to be utilized in estimating the depth of rock fractures. The performances of these techniques were re-evaluated after filling the artificial fractures with another material to simulate natural infills.

• 한국안전학회지
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• 제36권2호
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• pp.32-38
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• 2021

This paper suggests an approach to evaluate the reliability of an intelligent power module with information deficiency of prior distribution and the characteristics of censored data through Bayesian statistics. This approach used a prior distribution of Bayesian statistics using the lifetime information provided by the manufacturer and compared and evaluated diffuse prior (vague prior) distributions. To overcome the computational complexity of Bayesian posterior distribution, it was computed with Gibbs sampling in the Monte Carlo simulation method. As a result, the standard deviation of the prior distribution developed using simple information was smaller than that of the posterior distribution calculated with the diffuse prior. In addition, it showed excellent error characteristics on RMSE compared with the Kaplan-Meier method.

• 한국도서관정보학회지
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• 제47권4호
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• pp.489-510
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• 2016

중앙기록물관리기관이 제정한 원내표준 NAK/G 8-1:2013(v.1.0)에는 종이기록물의 영구보존용 마스터 파일 포맷으로 TIFF, PNG, PDF/A, JPEG 2000 파일 등을 명시하고 있다. 본 연구는 기존 포맷들과 함께 마스터 파일의 요건을 갖춘 JPEG 포맷을 추가하는 표준화 가능성에 대해 검토하였다. 먼저 JPEG 포맷이 갖고 있는 고유의 특징을 소개하고, 대표적인 마스터 파일 표준 포맷인 TIFF 포맷과의 특징 등을 비교 분석과정을 통하여, JPEG 포맷이 마스터 파일 포맷의 기능상의 요건이라는 대전제를 만족하므로 중앙기록물관리기관의 원내표준 내 JPEG 포맷을 추가하는 표준화 필요성을 주장하였다. 본 연구의 의의는 최근 가장 범용적으로 생산되어 지고 있는 JPEG 포맷을 영구보존용 마스터 파일 기본 요건을 충족하는 원내표준 포맷에 추가함으로써, 디지털화 된 종이기록물 원본의 진본성, 범용성, 편의성, 실용성 및 호환성 등 다양한 편익을 이용자들에게 제공할 수 있는 표준 환경을 마련했다는 것이다.

• Korean Journal of Radiology
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• 제22권12호
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• pp.2017-2025
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• 2021

Objective: To evaluate the accuracy and clinical efficacy of a hybrid Greulich-Pyle (GP) and modified Tanner-Whitehouse (TW) artificial intelligence (AI) model for bone age assessment. Materials and Methods: A deep learning-based model was trained on an open dataset of multiple ethnicities. A total of 102 hand radiographs (51 male and 51 female; mean age ± standard deviation = 10.95 ± 2.37 years) from a single institution were selected for external validation. Three human experts performed bone age assessments based on the GP atlas to develop a reference standard. Two study radiologists performed bone age assessments with and without AI model assistance in two separate sessions, for which the reading time was recorded. The performance of the AI software was assessed by comparing the mean absolute difference between the AI-calculated bone age and the reference standard. The reading time was compared between reading with and without AI using a paired t test. Furthermore, the reliability between the two study radiologists' bone age assessments was assessed using intraclass correlation coefficients (ICCs), and the results were compared between reading with and without AI. Results: The bone ages assessed by the experts and the AI model were not significantly different (11.39 ± 2.74 years and 11.35 ± 2.76 years, respectively, p = 0.31). The mean absolute difference was 0.39 years (95% confidence interval, 0.33-0.45 years) between the automated AI assessment and the reference standard. The mean reading time of the two study radiologists was reduced from 54.29 to 35.37 seconds with AI model assistance (p < 0.001). The ICC of the two study radiologists slightly increased with AI model assistance (from 0.945 to 0.990). Conclusion: The proposed AI model was accurate for assessing bone age. Furthermore, this model appeared to enhance the clinical efficacy by reducing the reading time and improving the inter-observer reliability.

• 한국전문물리치료학회지
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• 제24권3호
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• pp.40-46
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• 2017

Background: The active knee extension (AKE) test commonly used to assess the flexibility of the hamstring muscles. Many researchers have tested the reliability of the AKE test; however, no published studies have examined the intrarater and interrater reliability of the AKE test using a PBU. Objects: The purpose of this study was to determine the intrarater and interrater reliability of the AKE test performed with a pressure biofeedback unit (PBU) on healthy subjects. Methods: Sixteen healthy male participants volunteered and gave informed consent to participate in this study. Two raters conducted AKE tests independently with a PBU. Each knee was measured twice, and the AKE testing was repeated one week after the first round of testing. Results: The interrater reliability's intraclass correlation coefficients ($ICC_{2,1}$) were .887~.986 for the right knees and .915~.988 for the left knees. In addition, the intrarater (test-retest) reliability ($ICC_{3,1}$) values ranged between .820~.915 and .820~.884 for Raters 1 and 2, respectively. The values for the standard error of mesurement were low for all tests ($.81{\sim}2.97^{\circ}$); the calculated minimum detectable change was $2.24{\sim}8.21^{\circ}$. Conclusion: These findings suggest that the AKE test performed with a PBU had excellent interrater and intrarater reliability for assessing hamstring flexibility in healthy young males.

• 대한통합의학회지
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• 제5권1호
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• pp.43-53
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• 2017

Purpose : To examine the relative absolute reliability and validity of step test (ST) scores in subjects with chronic stroke. Method : A total of 27 stroke patients, participated in the study. A relative reliability index (intraclass correlation coefficient, ICC) was used to examine the level of agreement of inter-rater test-retest reliability for ST score. Absolute reliability indices, including the standard error of measurement(SEM) and the minimal detectable change (MDC), and limits of agreement by Bland and Altman analysis. The validity was demonstrated by spearman correlation of ST score with 10 m Walk Test (10mWT), Fugl-Meyer Assessment-Lower/Extremity (FMA-L/E)-total score, Berg Balance Scale (BBS)-total score. Result : An excellent inter-rater reliability in ST scores was found (paretic, ICC=0.993~0.996; nonparetic, ICC=0.982~0.991). In addition, excellent test-retest reliability was found (paretic, ICC=0.992; nonparetic, ICC=0.967). It all showed acceptable SEM of the ST score as paretic and nonparetic were 0.22 and 0.46 respectively (average score <10 %), and the MDC of the paretic and nonparetic were 0.61 and 1.27 respectively (possible highest score <20 %). indicating that measures had a small and acceptable measurement error. The ST score of paretic and nonparetic were also found to be significantly associated with 10MWT (r=0.77~0.79), FMA-LE scores (r=0.73~0.81) and BBS scores (r=0.72~0.76). Conclusion : The ST showed highly sufficient Inter-rater test-retest agreement and validity and acceptable measurement errors caused by due to chance variation in measurement. It also can be used by clinicians and researchers to assess the balance and mobility performance and monitor functional change in chronic stroke patients.

• Physical Therapy Rehabilitation Science
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• 제8권4호
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• pp.194-201
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• 2019

Objective: This study aimed to investigate the reliability and validity of muscle thickness (MT) and pennation angle (PA) measurements of the ankle muscle, including the tibialis anterior (TA) and the medial gastrocnemius (MGCM), using a hands-free fixed probe and to compare it with the conventional linear probe. Design: Observational inter-rater reliability study. Methods: Thirty-three healthy subjects (20 male, 13 female) were included. In all subjects, ultrasound images were acquired from the TA and MGCM using a hands-free fixed probe and a conventional linear probe in random sequence by two examiners at two time-points within a 7-day interval. MT and PA were calculated on the taken images. Intra-class correlation coefficients (ICC), 95% confidence intervals, standard error of measurement and the Pearson's correlation coefficient were used to estimate reliability and validity. And also, Bland-Altman plots were generated for a visual representation of MT and PA at the TA and MGCM. Results: The ICC for all intra-rater reliability was 0.943 to 0.995 and that for all inter-rater reliability was 0.928 to 0.993, indicating excellent reliability. A significantly high correlation was observed between MT and PA at the TA and MGCM with use of the hands-free fixed probe and the conventional linear probe (r>0.938; p<0.001). Conclusions: The hands-free fixed probe provided excellent images for measurement of the MT and PA of the TA and MGCM and is a useful device for making clinical measurements of muscle structure without grasping of the probe.