• 한국추진공학회지
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• 제13권6호
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• pp.8-16
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• 2009

고압 축소형 연소기의 개발에 관하여 기술하였다. 헤드부와 챔버부가 분리형인 연소기와 일체형 재생냉각 방식의 연소기 등 총 4기의 연소기가 개발되었다. 축소형 연소기의 연소 압력은 70 bar이고, 추진제 유량은 5.1~9.1 kg/s이다. 연소성능의 향상을 위해 추진제 유량, 분사기의 recess 수 등을 변화시켰고, 이를 연소시험을 통해 확인하였다. 또한 실물형 연소기에 적용할 재생냉각 채널과 막냉각의 설계 및 제작 기술을 본 축소형 연소기에 적용, 검증하였다.

• 대한간호학회지
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• 제44권6호
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• pp.630-638
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• 2014

Purpose: The purpose of this study was to develop a scale to evaluate stress in elderly patients with coronary artery diseases (CAD) and to examine validity and reliability of the scale. Methods: The development process for the preliminary scale included construction of a conceptual framework and initial items, verification of content analysis, sentence correction, and pilot study. This study was conducted using a questionnaire survey with one-to-one interviews during January and February, 2012. Participants were 240 elderly patients with CAD. Data were analyzed using item analysis, factor analysis, criterion related validity, and internal consistency. Results: The developed scale consisted of 32 items and 6 factors - aging and disease (7 items), family relations (5 items), anxiety and withdrawal (9 items), management of daily living (3 items), compliance of medical regimen (4 items), poverty and finance (4 items), and explained 68.5% of total variance. The scale had significantly positive correlation with the Korean Perceived Stress Scale (KPSS). Cronbach's alpha was .96, and Guttman split half coefficient was .91. Conclusion: Results indicate that the Stress Scale for Elderly Patients with CAD has validity and reliability, and is a suitable scale in health care settings to assess stress in elderly patients with CAD.

• 아동학회지
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• 제9권2호
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• pp.1-28
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• 1988

The purpose of this study was to develop a behavior rating scale for the evaluation of children's development for utilization by preschool teachers. The procedures for the study included content validation, pilot test, and main study. A total of 97 items were retained after the content validation and pilot test. The items of the scale were grouped into five areas (physical, language, cognitive, emotional, and social development) and 11 sub-areas. The resulting "Behavior Rating Scale for Preschool Children" was administered to 479 boys and girls, 3-6 through 6-5 years of age, selected from 10 different kindergartens and early education centers in Seoul, Pusan, and Chonju. The analysis of data was done with SPSS computer programs, including item analysis, Cronbach's ${\alpha}$ for reliability, factor analysis to test construct validity, two-way ANOVA to test age and sex differences, and percentile norms. The 97 items of the scale were found to be satisfactory in terms of item discrimination with indices ranging from .31 to .73. Cronbach's ${\alpha}$ was .98 for the total scale and ranged from .87 to .93 in specific domains, which was considered satisfactory. The factors extracted from each area were consistent with the educational objectives of the Yonsei Open Education Program except for emotional development. The intercorrelations among the domains were relatively high, ranging from .56 to .81. Age differences were significant in cognitive, physical, and language development, but not significant in social and emotional development. Sex differences were significant in all areas with girls higher on the average than the boys. Percentile ranks were drived from the total score for each age group and quartiles were calculated for sub-scores in each domain.

• 한국군사과학기술학회지
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• 제21권6호
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• pp.776-783
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• 2018

This paper proposes an improved test and evaluation methodology to be conducted for a in-flight threat-countermeasure encounter scenario. Although the conventional test method adopted in the precedent researches allows high precision and safety, such full-scale method is practically not appropriate to apply to small-scale test rounds for evaluating the subparts of the ammunition. To address this problem, this study suggests a readily-applicable, small-scale test and evaluation method of the subpart of the ammunition in firing test. In the threat-countermeasure encounter scenario, the results of several tests demonstrate that the proposed technique does not deteriorate the precision when the engagement point should be adjusted.

• 대한가정학회지
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• 제44권1호
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• pp.1-10
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• 2006

The purpose of this study was to develop a scale to access a creative home environment for preschool children and to examine its validity and reliability. The subjects were 296 children aged 5 to 6 years(148 males and 148 females) and their parents. The methods for data analysis included item analysis, factor analysis for construct validity, Pearson correlations between the rating scale for creative characteristics of preschoolers(RSCCP) and this scale for concurrent validity, and Cronbach's ${\alpha}$ for reliability. The 44 items of the scale were found be satisfactory in terms of item response distribution and item discrimination. Four factors were extracted from the factor analysis: the subscales labelled 'respect for the child', 'enriched learning environment', 'stimulation of independence' and 'family pressure'. The concurrent validity of this scale was accessed by computing the correlation measures of RSCCP with this scale. Most coefficients were significant. Cronbach's ${\alpha}$ ranged from.75 to.86 for the 4 subscales and.85 for the total scale.

• 아동학회지
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• 제26권4호
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• pp.173-188
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• 2005

To examine relationships between learning-related social skills(LRSS) and literacy development a sample of 167 children aged 5-6 years were selected from 3 preschools in Seoul. Instruments for measuring LRSS were the cooperation, assertion, and self-control scales of the Social Skills Rating System (Gresham & Elliott, 1990) and the mastery behaviors scales of the Child Behavior Rating Scale (Bronson, et al. 1990). Literacy development was measured by the Concepts about Print(Woon, 1999), the Learning Readiness Scale(Korean Educational Development Institution 1998), and the Writing Development Scale(Lee, 1997). Teachers rated children's LRSS. Data were analyzed by mean, standard deviation, t-test, bivariate correlation, and regression analysis. LRSS correlated with children's literacy development. Mastery behaviors were the best predictor of literacy development.

• Corrosion Science and Technology
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• 제7권3호
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• pp.182-186
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• 2008

The microstructures of the oxide scale developed at high temperature on steels are very complex and their development depends on many factors including time, temperature, oxidation conditions and alloying elements. The classical model of an oxide scale on steel consisting of wüstite, magnetite and haematite layers, is more complicated in reality and its properties change with the factors that affect their development. An understanding of the oxide scale formation and its properties can only be achieved by careful examination of the scale microstructure. The oxide scale microstructure may be difficult to characterise by conventional techniques such as optical or standard scanning electron microscopy. An unambiguous characterisation of the scale and the correct identification of the phases within the scale are difficult unless the crystallographic structure for each phase in the scale is considered and a simultaneous microstructure-microtexture analysis is carried out. In the current study Electron Backscatter Diffraction (EBSD) has been used to investigate the microstructure of iron oxide layers grown on low carbon steels at different times and temperatures. EBSD has proved to be a powerful technique for identifying the individual phases in the oxide scale accurately. The results show that different grain shapes and sizes develop for each phase in the scale depending on time and temperature.

• 대한간호학회지
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• 제45권4호
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• pp.613-624
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• 2015

Purpose: The purpose of this study was to develop a scale to evaluate empowerment in woman with breast cancer and to examine the validity and reliability of the scale. Methods: The development process for the initial items included a literature review, interviews, and construction of a conceptual framework. The identified items were evaluated for content validity by experts, resulting in 3 factors and 48 preliminary items. Participants were 319 women with breast cancer recruited to test reliability and validity of the preliminary scale. Data were analyzed using item analysis, confirmatory factor analysis, criterion related validity, internal consistency and test-retest reliability. Results: The final scale consisted of 30 items and 3 factors. Factors, including 'intrapersonal factor' (14 items), 'interactional factor' (8 items), and 'behavioral factor' (8 items), were drawn up after confirmatory factor analysis. Goodness of fit of the final research model was very appropriate as shown by ${\chi}^2/df=1.86$, TLI=.90, CFI=.92, SRMR=.06, and RMSEA=.05. Criterion validity was evaluated by total correlation with the Cancer Empowerment Questionnaire .78. Cronbach's alpha for total items was .93 and test-retest reliability was .69. Conclusion: Findings from this study indicate that the scale can be used in the development of nursing interventions to promote the empowerment of women having breast cancer.

• 아동학회지
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• 제33권6호
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• pp.85-107
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• 2012

In this study, the Infants & Toddlers' Playfulness Scale(ITPS) was developed and its reliability and validity were examined. The participants in this study consisted of 656 parents whose children were 8 to 36 months old. Five factors were identified from the results of the exploratory factor analysis performed on the 29 items that had been derived by analyzing existing research. The Goodness of Fit Indices(GFIs) of the confirmatory factor analyses, performed on the 1st-order 5-factor model and the 2nd-order one factor model, were both satisfactory. Concurrent validity was established by the high correlations of r = .631~.808(p < .01) between each factor of the ITPS and the total score of the Children's Playfulness Scale(CPS), an existing measure for children's playfulness. The reliability of each factor, as measured by Cronbach's ${\alpha}$, ranged from .773 to .883. Consequently, the ITPS developed in this study can be seen as a reliable and valid scale that can be used by parents to measure the playfulness of their infants and toddlers in a multi-dimensional manner.

• 성인간호학회지
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• 제15권2호
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• pp.267-277
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• 2003

Purpose: The purpose of this study was to evaluate the applicability of braden scale to assess pressure ulcer risk patients and to identify additional risk factors of pressure sores in an neurologic intensive care unit. Method: The subjects of this study were 66 patients in neurologic intensive care units. Data was prospectively collected from Sep. to Dec., 2002. Data were analyzed by mean, percentage, t-test, chi-square, discriminant analysis using Spss pc+. Result: The results of this study were as follows: 1) There was a significant difference between scoring of braden scale and pressure ulcer development. The subscales that predicted pressure ulcer development using braden scale only were sensory perception, moisture, mobility, friction & shear. By using these subscales, sensitivity was 86.7%, and specificity was 61.1%, and total hit ratio was 72.7%. 2) Additional pressure ulcer risk factors which showed significance for discriminating two group were protein, albumin, gender, level of consciousness, pattern of bowel elimination. By using the combination of these additional risk factors in addition to the braden scale, total hit ratio increased to 84.8%. Conclusion: This data suggest that albumin, protein, gender, level of consciousness, pattern of bowel elimination in addition to the braden scale should be included in the pressure sore assessment tool.