• 한국위성정보통신학회논문지
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• 제7권1호
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• pp.86-91
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• 2012

본 논문에서는 ETRI가 개발하여 천리안위성에 탑재한 Ka대역 안테나의 빔 커버지리 검증 결과에 대하여 기술하였다. 위성이 발사되면 위성체 및 위성에 탑재된 탑재체가 발사 환경과 우주 환경을 견디고 본래의 기능 및 성능을 발휘하는지 확인하고자 In Orbit Test(IOT)를 진행한다. ETRI는 IOT를 통하여 측정한 천리안위성 Ka대역 안테나의 방사패턴이 위성 발사 전에 지상에서 측정한 패턴과 유사한 특성을 보여주고 있음을 확인하였다. 이를 통하여 천리안위성 Ka대역 안테나의 성능이 위성의 발사 환경을 무사히 견디고 우주환경에서 당초 ETRI가 설계한 대로 정상적으로 나오고 있음이 검증되었다. IOT 후에 ETRI는 천리안위성 Ka대역 안테나의 빔 커버리지가 당초 설계한대로 잘 형성되어 있는지 확인하기 위하여 한반도 전역에서 측정차량을 이용하여 필드측정을 실시하였다. 빔 커버리지를 측정하기 위하여 기준지점인 ETRI를 포함, 한반도 외각 지역 및 제주도를 중심으로 총 17지점을 선별하여 이동 측정차량을 이용하여 필드 측정을 실시하고, 이를 지상시험(CATR) 결과와 비교 분석하였다. 분석한 결과 천리안위성 통신탑재체의 빔 커버리지가 당초 ETRI가 설계한 대로 한반도 전역에서 정상적으로 형성되어 있음을 확인할 수 있었다.

• 한국정밀공학회지
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• 제20권9호
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• pp.205-213
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• 2003

This study describes the mathematical equation of drawdown test model and introduces the experimental test apparatus and procedure to estimate the desorption rate ratio of a filter. The characteristics of a hydraulic filtration system of drawdown test were demonstrated by numerical simulation for various properties of filters and operation conditions. Experiments for three kinds of fuel filters were conducted according to the proposed test method. And the test results of desorption rate ratio were compared with those values anticipated in precedent multipass filtration tests. Experimental results revealed the validation of drawdown test method proposed in this study. Domestic fuel filter yielded high desorption rate ratio comparing with other foreign products, which means that the Beta ratio decreases a lot during the test. The results also showed that filtration system model could be developed including desorption rate ratio to estimate the variable Beta ratio in service life.

• 시스템엔지니어링학술지
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• 제14권2호
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• pp.83-88
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• 2018

Software has become an integral part of almost any system, triggered by the ever-growing demand for automation and artificial intelligent throughout engineering domains. The complexities of software-centric systems are also increasing, which make software test efforts become essential in software development projects. In this study, we applied systems engineering methodology in generating software test cases. We found out the similarities between requirements analysis and traceability concept of systems engineering and test specification contents of software test. In terms of acceptance test, software test cases could be considered as validation requirements. We also suggested a method to determine test order using a SysML modeling tool.

• Journal of Information Processing Systems
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• 제6권2호
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• pp.197-208
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• 2010

Test scenarios can be derived based on some system models for requirements validation purposes. Model-based test suite reduction aims to provide a smaller set of test scenarios which can preserve the original test coverage with respect to some testing criteria. We are proposing to apply Formal Concept Analysis (FCA) in analyzing the association between a set of test scenarios and a set of transitions specified in a state machine model. By utilizing the properties of concept lattice, we are able to determine incrementally a minimal set of test scenarios with adequate test coverage.

• Clinical and Experimental Pediatrics
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• 제54권11호
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• pp.463-469
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• 2011

Purpose: To validate the Dinamap ProCare 200 blood pressure (BP) monitor against a mercury sphygmomanometer in children 7 to 18 years old in accordance with the 2010 International Protocol of European Society of Hypertension (ESH-IP2) and the British Hypertension Society (BHS) protocol. Methods: Forty-five children were recruited for the study. A validation procedure was performed following the protocol based on the ESH-IP2 and BHS protocols for children and adolescents. Each subject underwent 7 sequential BP measurements alternatively with a mercury sphygmomanometer and the test device by trained nurses. The results were analyzed according to the validation criteria of ESH-IP2. Results: The mean (${\pm}SD$) difference in the absolute BP values between test device and mercury sphygmomanometer readings was $1.85{\pm}1.65$ mmHg for systolic BP (SBP) and $4.41{\pm}3.53$ mmHg for diastolic BP (DBP). These results fulfilled the Association for the Advancement of Medical Instrumentation criterion of a mean${\pm}$SD below $5{\pm}8$ mmHg for both SBP and DBP. The percentages of test device-observer mercury sphygmomanometer BP differences within 5, 10, and 15 mmHg were 96%, 100%, and 100% for SBP, and 69%, 92%, and 100% for DBP, respectively, in the part 1 analysis; both SBP and DBP passed the part 1 criteria. In the part 2 analysis, SBP passed the criteria but DBP failed. Conclusion: Although the Dinamap ProCare 200 BP monitor failed an adapted ESH-IP2, SBP passed. When comparing BP readings measured by oscillometers and mercury sphygmomanometers, one has to consider the differences between them, particularly in DBP, because DBP can be underestimated.

• 한국초등과학교육학회지:초등과학교육
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• 제36권3호
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• pp.219-226
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• 2017

In this study, the reliability and validity of the retrospective pre-post test were analyzed in order to solve the problem of traditional pre-post test including response shift bias. Samples of the study were 162 elementary school students who are studying at the S university gifted education center in Seoul. Before completion of the field trip, we conducted pre test of science-related attitudes. After completion of the field trip, respondents were asked to compare their responses of pre and post science-related attitudes to quantitatively analyze the commonalities and differences of the two tests. To find out more characteristics, qualitative data such as daily records and interview were also gathered and analyzed. The major results of the study are as follows. First, for the paired t-test, there was no statistically significant difference between separate pre-test scores and retrospective pre-test. There was a very high correlation between the separate pre-test scores and the retrospective pre-test. Second, there were significant differences in all seven sub-factors of science-related attitudes between the retrospective pre-test and the post-test. Third, the separate pre-test scores showed a slightly higher tendency than the retrospective pre-test scores. This suggests that the response shift bias appears when it is performed the separate pre-test in affective domain. As a result of the interview, it was found that the evaluation standards of separate pre-test did not match with those of post-test. Forth, internal consistency reliability of the retrospective pre-test was higher than that of the separate pre-test. However, there were significant differences in six factors of science-related attitudes excluding the 'social implications of science' between the separate pre-test and the post-test. Based on these results, the retrospective pre-post test design provides simplicity and convenience to both respondents and investigators, as it is done with one test. The retrospective pre-post test design can be regarded as a valid design for the self-report measurement of affective domain on a single experimental group.

• 보건행정학회지
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• 제23권4호
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• pp.434-444
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• 2013

Background: Regional Cardiocerebrovascular Centers (RCC) were established for the prevention and treatment of cardiocerebrovascular disease and funded by the Ministry of Health and Welfare. The purpose of this study was to develop and validate the measurement tool of public benefits in RCC. Methods: Through the intensive literature review, experts surveys and their repetitive feedback, we selected the 46 items about the public benefits in RCC. Development of measurement tool involved content validity test using Content Validity Index (CVI), construct validity test through factor analysis and reliability test. Results: Thirty-five items were selected by content validity test, which CVI was 0.08 or higher. Through the construct validity test, 32 items in 7 factors were derived. And Cronbach's alpha was 0.951. Finally, public benefits measurement tool is composed of 32 items in 7 factors which are comprehensiveness of health care services, market complement, emergency care, cost, governance, quality improvement, and government control. Conclusion: Though we developed the measurement tool of public benefits in RCC, it would be utilized to measure the public benefits of various health agencies.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• 제20권1호
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• pp.22-26
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• 2017

Purpose: The diagnosis of cow's milk (CM) allergy is a challenge. The Cow's Milk-related-Symptom-Score ($CoMiSS^{TM}$) was developed to offer primary health care providers a reliable diagnostic tool for CM related symptoms. The predictive prospective value of the $CoMiSS^{TM}$ was evaluated in three clinical trials. Methods: Pooled analyses of the three studies were conducted based on regressing the results of the month-1 challenge test on the month-1 $CoMiSS^{TM}$, adjusting for baseline $CoMiSS^{TM}$ using a logistic regression model. In addition a logistic regression model was also fitted to the month-1 challenge test result with the change in $CoMiSS^{TM}$ from baseline as a predictor. Results: Results suggest that infants having a low $CoMiSS^{TM}$ (median, 5) after 1 month dietary treatment free from intact CM protein have a significant risk of having a positive challenge test (odds ratio, 0.83; 95% confidence interval, 0.75-0.93; p=0.002). Pooled data suggest that the change in $CoMiSS^{TM}$ from baseline to month-1 can predict CM related symptoms as a confirmed diagnosis according to the challenge test at month-1. However, in order to validate such a tool, infants without CM related symptoms would also need to be enrolled in a validation trial. A concern is that it may not be ethical to expose healthy infants to a therapeutic formula and a challenge test. Conclusion: Pooled data analysis emphasizes that the $CoMiSS^{TM}$ has the potential to be of interest in infants suspected to have CM-related-symptoms. A prospective validation trial is needed.

• 대한간호학회지
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• 제35권6호
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• pp.1063-1071
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• 2005

Purpose: This study was done to develop and test validity and reliability of on instrument for predicting nursing intention for SARS patient care. Method: The psychometric properties of a SARS patient care attrition prediction tool, based on the Theory of Planned Behavior, were examined in this study. The Three-phase design involved a) salient beliefs generated from clinical nurses (n=43) b) content validation by expert panel evaluations(n=5) c) face validation by plot testing (n=10) d) and instrument validation in a cross sectional survey (n=299). Psychometric analysis of survey data provided empirical evidence of the construct validity and reliability of the instrument. Result: Principal component analysis verified the hypothesized 6-factor solution, explaining $68.2\%$ of variance, and Alpha coefficients of .7538 to .9389 indicated a high internal consistency of the instrument. Conclusion: The instrument can be used by nurse administrators and researcher to assess clinical nurses' salient beliefs about caring for SARS patients, guide tailored intervention strategies to effective caring, and evaluate the effectiveness of interventions.

• Journal of the Korean Data and Information Science Society
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• 제20권2호
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• pp.261-272
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• 2009

신용평가모형에서 두 집단의 판별력 검정방법 중의 하나로 두 분포함수의 동일성 검정을 위한 비모수적인 Kolmogorov-Smirnov (K-S) 검정방법이 대표적으로 적용되고 있다. 본 연구에서는 신용평가모형에서 두 분포함수의 동일성 검정을 위하여 K-S 검정 방법 외에 Cramer-Von Mises, Anderson-Darling, Watson 검정방법들을 소개하고 Joseph (2005)의 기준에 대응하는 판단기준을 제안한다. 또한 신용평가 자료와 유사한 상황 하에서의 모의실험을 통해서 불량률, 표본크기 그리고 제II종 오류율을 고려한 대안적인 판단기준을 제시하고 그 적용방법에 대해서 살펴본다.