• 비파괴검사학회지
• /
• 제10권1호
• /
• pp.29-37
• /
• 1990

In this study the disbonding tests of adhesively bonded Al/Al honeycomb structures were performed by ultrasonic methods. Ultrasonic C-scan squiter method and ultrasonic surface wave attenuation measuring method were applied for the detection of skin/core disbonding. The bonding quality of Al/Al honeycomb structures could be well evaluated by properly controlled ultrasonic parameters.

• 한국전문물리치료학회지
• /
• 제26권3호
• /
• pp.106-114
• /
• 2019

Background: It is difficult to assess whether community-dwelling frail older adults may remain pre-frail status or improve into a robust state without being directly checked by health care professionals. The health information perceived by older adults is considered to be one of best sources of potential concerns in older adult population. An online measurement system combined with item response theory (IRT) and computer adaptive testing (CAT) methods is likely to become a realistic approach to remotely monitor physical activity status of frail older adults. Objects: This article suggests an approach to provide a precise and efficient means of measuring physical activity levels of community-dwelling frail older adults. Methods: Article reviews were reviewed and summarized. Results: In comparison to the classical test theory (CTT), the IRT method is empirically aimed to focus on the psychometric properties of individual test items in lieu of the test as a whole. These properties allow creating a large item pool that can capture the broad range of physical activity levels. The CAT method administers test items by an algorithm that select items matched to the physical activity levels of the older adults. Conclusion: An online measurement system combined with these two methods would allow adequate physical activity measurement that may be useful to remotely monitor the activity level of community-dwelling frail older adults.

• 비파괴검사학회지
• /
• 제18권1호
• /
• pp.27-32
• /
• 1998

비파괴검사를 이해하고 습득하기 위해 필수적인 실습 위주의 교육 환경을 대체할 수 있는 수단으로, 가상적인 실습 환경을 제공하는 지능형 교육 시스템을 설계하고, 이를 구현하였다. 용접부 및 다양한 제품을 검사하는데 필수적인 비파괴검사는 그 전문기술을 이해하기 위해 다양한 현장 경험을 필요로 할 뿐만 아니라, 기술지식의 지속적인 유지를 위해 반복적인 교육과 훈련을 필요로 한다. 이러한 문제를 해결하기 위해 개인용 컴퓨터를 이용하여 개별학습이 가능한 지능형 교육 시스템을 개발하였으며, 가상 실습 환경의 구축과 개별학습을 효율적으로 지원하기 위해 학습 결과를 자기진단 할 수 있는 평가 시스템의 연구가 필요하다.

• Genomics & Informatics
• /
• 제14권4호
• /
• pp.187-195
• /
• 2016

In genetic association studies with high-dimensional genomic data, multiple group testing procedures are often required in order to identify disease/trait-related genes or genetic regions, where multiple genetic sites or variants are located within the same gene or genetic region. However, statistical testing procedures based on an individual test suffer from multiple testing issues such as the control of family-wise error rate and dependent tests. Moreover, detecting only a few of genes associated with a phenotype outcome among tens of thousands of genes is of main interest in genetic association studies. In this reason regularization procedures, where a phenotype outcome regresses on all genomic markers and then regression coefficients are estimated based on a penalized likelihood, have been considered as a good alternative approach to analysis of high-dimensional genomic data. But, selection performance of regularization procedures has been rarely compared with that of statistical group testing procedures. In this article, we performed extensive simulation studies where commonly used group testing procedures such as principal component analysis, Hotelling's $T^2$ test, and permutation test are compared with group lasso (least absolute selection and shrinkage operator) in terms of true positive selection. Also, we applied all methods considered in simulation studies to identify genes associated with ovarian cancer from over 20,000 genetic sites generated from Illumina Infinium HumanMethylation27K Beadchip. We found a big discrepancy of selected genes between multiple group testing procedures and group lasso.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 2005년도 심포지엄 논문집 정보 및 제어부문
• /
• pp.84-86
• /
• 2005

The digital systems such as PLC or DCS have been applied to non-safety systems of nuclear power plants because of many difficulties in using analog systems. Nowadays, digital systems have been applied to safety systems of the plants such as reactor protection system. One of the main advantages of digital systems is applicability of automatic testing methods to the systems. The protection system requires high-reliability and high-availability because it shall minimize the propagation of abnormal or accident conditions of nuclear power plants. The calculation of reliability and availability of systems depends on the maintenance period of the system. In general, the maintenance period of the protection system is one-month in case of the manual test. However, the cycle of test can be shortened in several hours by using automatic periodic testing. The reliability and availability of the system is better when test period is shortened because the reliability and availability is inverse proportion to the test period. In this research, we developed the automatic periodic testing method for KNICS Reactor Protection System, which can test the system automatically without an operator or a tester. The automatic testing contained all functions of reaction protection systems from analog-to-digital conversion function of the bistable Processor to the coincident trip function of the coincident processor. By applying the automatic periodic testing to reaction system, the maintenance cost can be cut down and the reliability can be increased.

• 품질경영학회지
• /
• 제49권3호
• /
• pp.281-297
• /
• 2021

Purpose: The purpose of this study was to select factors affecting the global competitiveness of testing and certification bodies and to develop evaluation indicator. Methods: Considering the industrial characteristics of Korea, the electrical and electronic test and certification field was selected as the research subject. As a research method, various factors were extracted through exploratory research such as theoretical considerations on the competitiveness of testing and certification bodies and analysis of the growth process of global testing and certification bodies, and focused interviews and surveys were conducted with conformity assessment experts. Results: The 16 factors affecting the global competitiveness of testing and certification institutions were identified. Among the 4 PEST factors, the technological factor had the highest importance, followed by the economic factor, the social factor, and the political factor. The average of the 16 factors was 0.0625, and the 8 factors above the average included 4 technological factors, 3 economic factors, and 1 social factor, but did not include political factors. The factor with the greatest weight was Standardization Capability for Testing & Certification 0.105. Conclusion: It can be used to evaluate the global competitiveness level of domestic testing and certification bodies using evaluation indicators and to establish strategies for strengthening global competitiveness.

• 한국포장학회지
• /
• 제8권1호
• /
• pp.1-10
• /
• 2002

각 국가 권역별 이행실험방법에 따라 지방성 및 고온가열 식품 포장재에서의 시뮬란트별 항산화제와 DEHA의 특정이행량을 비교하였다. 고온 가열용 식품 포장재의 경우 일부 두께가 두꺼운 필름, 예를 들어 PP 필름에서는 각 국가 권역별 시뮬란트 종류와 온도 조건의 차이에 따른 항산화제의 이행량의 차이가 나타났다. 미국이나 유럽연합에서 지방성 식품의 시뮬란트를 이용하여 얻어진 실험치에 $2{\sim}5$의 reduction factor가 계산되는 것을 감안한다면 아시아 조건하에서의 이행치가 유의적으로 높아지는 결과를 초래하게 된다. 아시아의 이행 실험 조건은 해당포장재의 온도 노출 조건에 따라 다양하게 설정될 필요성이 제기되었다.

• Communications for Statistical Applications and Methods
• /
• 제7권2호
• /
• pp.549-562
• /
• 2000

Default Bayes factors are computed to test the equality of one Poisson population mean and the equality of two independent Possion population means. As default priors are assumed Jeffreys priors, noninformative improper priors, and default Bayes factors such as three intrinsic Bayes factors of Berger and Pericchi(1996, 1998), the arithmetic, the median, and the geometric intrinsic Bayes factor, and the factional Bayes factor of O'Hagan(1995) are computed. The testing results by each default Bayes factor are compared with those by the classical method in the simulation study.

• 한국콘크리트학회:학술대회논문집
• /
• 한국콘크리트학회 1993년도 가을 학술발표회 논문집
• /
• pp.61-64
• /
• 1993

This study is aimed to analyze the influencing factor on the non-destructive testing by measuring rebound number of schmidt hammer and ultrasonic pulse velocity according to the variation of recycled aggregate kinds. And this study is to provide the reference data on application of practical use.

• Communications for Statistical Applications and Methods
• /
• 제7권1호
• /
• pp.151-164
• /
• 2000

In this paper we consider the Bayesian hypothese testing for independence and symmetry in Freund's bivariate exponential model with censored data In Bayesian testing problem we use the noninformative priors for parameters which are improper and are defined only up to arbitrary constants. And we use the recently proposed hypotheses testing criterion called the intrinsic Bayes factor. Also we derive the arithmetic and median intrinsic Bayes factors and use these results of analyze some data sets.