• Journal of Applied Reliability
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• v.9 no.2
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• pp.93-106
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• 2009

GPS(Global positioning system) system is widely used in artificial satellite, ground controlled approach system as well as in end-user environment such as in the automobile. It is exposed to a very diverse environment and consists of many complicated components and therefore needs careful approach to the enhancement of reliability of the item. In this article reliability standards for the GPS system are established in terms of quality certification tests and failure rate tests.

• Journal of Aerospace System Engineering
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• v.2 no.4
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• pp.25-30
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• 2008

In general, we utilize momentum wheel to control spacecraft. It needs vacuum test to analyze the effect of space environments. The conventional vacuum connector which is composed of steel has problems for test with built in momentum wheel because of weight, thermal expansion, etc. We suggest possibility to manufacture the vacuum connector using aluminum mount, epoxy and industrial D-Sub considering cost, weight. We verify the performance through vacuum test.

• KIEAE Journal
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• v.9 no.2
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• pp.53-58
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• 2009

There are increasing developments and uses of functional building materials are recently developed and introduced to the test method for the materials. Especially, moisture problem has a major role are also being established in indoor air quality problems. The purpose of this study is to evaluate the water vapour adsorption/desorption property of a ceiling material. The variation of the temperature and moisture were measured with the application materials by mock up test based on JIS 1470-1. The result shows that water vapour adsorption/desorption property of ceiling material is appeared in changes of moisture adsorption and desorption in comparison with that of a general ceiling material. Therefore, in case of decreasing and increasing in humidity, these materials can be used as an finishing material to sustain comfort condition.

• Korean Medical Education Review
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• v.15 no.3
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• pp.112-119
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• 2013

Most medical colleges in Korea have been shifting from traditional education to outcome-based education, which is the general trend in medical education. The purpose of this study was to make some suggestions in light of the reality and challenges of student assessment in medical education from the perspective of outcome- based education. First, those who are responsible for student assessment should be diversified to include faculty, residents, students, and evaluation committee members. They need separate roles in educational evaluation, so evaluation competencies are required for them. Second, various methods for evaluation and score interpretation can be used for effective evaluation. We can adopt diagnostic, formative, and summative evaluation functionally, and the norm-referenced, criterion-referenced, growth-referenced, and ability-referenced evaluation based on criteria for score interpretation. Finally, various evaluation domains and test forms can be administered together in the common lectures in the medical school. We can test not only knowledge but also skills and attitudes, with diverse test forms such as supply and performance types.

• Transactions of Materials Processing
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• v.18 no.1
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• pp.73-79
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• 2009

In order to investigate the formability of friction stir welded(FSW) tailor welded blanks(TWB) with respect to the base material's directional combination, aluminum alloy AA6111-T4 sheets were welded with three different conjoining types: RD-RD, TD-RD and TD-TD. Here, RD and TD represent rolling and transverse directions, respectively. For experimental formability study, three tests with gradual complexity were performed: the simple tension test with various weld line directions for uni-axial elongation, the hemisphere dome stretching test for biaxial stretching and the cylindrical cup deep drawing test. As a result, all three forming tests showed that RD-RD type samples exhibited the best formability, while TD-TD type sheets showed the least formability performance.

• Proceedings of the KSME Conference
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• 2008.11b
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• pp.2070-2075
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• 2008

Identification of steady-state is the first step in developing a fault detection and diagnosis (FDD) system. In a complete FDD system, the steady-state detector will be included as a module in a self-learning algorithm which enables the working system's reference model to "tune" itself to its particular installation. In this study, a steady-state detector of a residential air conditioner based on moving windows was designed. Seven representing measurements were selected as key features for steady-state detection. The optimized moving window size and the feature thresholds was suggested through startup transient test and no-fault steady-state test. Performance of the steady-state detector was verified during indoor load change test. From the research, the general methodology to design a moving window steady-state detector was provided for vapor compression applications.

• The KSFM Journal of Fluid Machinery
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• v.13 no.4
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• pp.11-17
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• 2010

The developed control valves, installed on the hot water distribution manifolds for the floor heating system, consist of the balancing valves and the shut-off valves. The balancing valve was designed to improve the flow control performance and to reduce the noise emitted from the valve by modification of the general V port. The port of the shut-off valve was designed with two ceramic plates, working by rotating upper plate, to improve the duration and to reduce the noise. For the evaluation of the new valves, the flow rate was measured and noise level test was carried out. The test results showed that the error of the flow rate accuracy test for the flow balance of each manifold circuit was less than ${\pm}3%$ and the noise level was less than 35 dB(A).

• Human Ecology Research
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• v.55 no.3
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• pp.221-232
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• 2017

This study analyzes the motivation for selecting child-care profession, job environment, director's transformational leadership associated with child-care center teacher's (lead teacher and head teacher) role performance. The subjects of this study were 336 teachers (lead teacher and head teacher) who worked in a child-care center located in Seoul and Gyeonggi-do. Data were collected through self-report questionnaires. Collected data were analyzed using the IBM SPSS Statistics ver. 23.0 program using t-test, F-test, analysis of variance, post-hoc analysis (Duncan), Pearson's correlation analysis, and multiple regression analysis. The results of the study are as follows. First, the study inquired on if the child-care center teacher's general characteristics (year) influence the child-care center teacher's role performance. Consequently, significant differences were not found in overall role performance according to teacher's career but not in the child-care center teacher's age, academic ability, and licensing. Second, the motivation for selecting profession (teaching aptitude, teacher's desire for social respect, and possibility of self-realization), job environment, and director's transformational leadership had a significant positive correlation with overall role performance. The motivation for selecting profession (without motives) had a significant negative correlation with overall role performance. Third, the strongest predictors of 'overall role performance' were teaching aptitude, variable of motivation for selecting child-care profession, and director's transformational leadership variable.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.1
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• pp.246-254
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• 2015

This study was conducted as a descriptive study with the aim of identifying the effects of safety knowledge and safety control on early childhood teachers' safety performance. Data collection for the study was carried out between October $10^{th}$ and $30^{th}$, 2014 by surveying 187 early childhood teachers working in child day care center and kindergarten located in P, K, & Y city. Measures were subjects' safety knowledge, safety control, and safety performance. For the analysis of the data, the statistical methods of frequency, mean and standard deviation, t-test, ANOVA, Pearson's correlation coefficients, and multiple regression analysis were employed. When the category of safety performance was analyzed by general features, marital status, educational career, and degree of assistance of safety education, there were significant differences. Safety performance correlated positively with safety knowledge and safety control. Factors affecting early childhood teachers' safety performance were identified in the order of safety knowledge and safety control and the explanatory power was 60.0%. The findings of the study indicate that in order to increase early childhood teachers' safety performance, their safety knowledge and safety control have to be enhanced.

• Journal of the Korea Convergence Society
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• v.9 no.10
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• pp.441-448
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• 2018

The purpose of this study was to investigate the factors affecting of hospital information system quality factors on user satisfaction and service innovation performance in general hospitals. Using 5-point Likert scale, survey was performed on 250 nurses on hospital information system quality, user satisfaction, and service innovation performance. Data were analyzed by t=test, ANOVA, correlation and regression analysis using SPSS WIN 24.0 program. The results showed that significant correlation between service innovation performance and independent variables was seen in system quality (r=0.644, p<.001), information quality (r=0.650, p<.001), service quality (r=0.629, p<0.001) and user satisfaction (r=0.831, p<.001). User satisfaction was a moderating variable between hospital information system quality and service innovation performance with explanatory power of 78.4%. Higher user satisfaction (B=0.557, p<.001) showed positive correlation with greater service innovation performance. Investigating the mediating role of user satisfaction between EMR quality and service innovation performance, it is suggested that importance of system quality, user friendly system support and service.