• 대한기계학회논문집A
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• 제21권1호
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• pp.93-103
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• 1997

Charpy V-notch impact tests were performed on the full-, half-and third-size specimens from two ferritic SA 508 Cl. 3 steels for nuclear pressure vessel. New normalization factors were proposed to predict the upper shelf energy(USE) and the ductile-brittle transition temperature(DBTT) of full-size specimens from the measured data on sub-size specimens. The factors for the USE and the DBTT are $(Bb^2/Kt); and; (Bb/R)^1/2/, $ respectively, where B the width, b the ligament size, $K_{t}$ the elastic stress concentration factor, and R the notch root radius. These correlations successfully estimated the USE and DBTT of the full-size specimens based on sub-size specimen data. In addition, the size effects were studied to develop the correlations among absorbed energy, lateral expansion(LE) and displacement. It was also found that the LE was able to be estimated from the displacement obtained by the instrumented impact test, and that the displacement would be used as a criterion for the toughness of the steels corresponding to change in their yield strength.h.

• 치위생과학회지
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• 제7권4호
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• pp.219-224
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• 2007

본 연구는 치과의료기관 내원환자들의 치주조직건강 인식도를 알아보기 위해 서울지역에 위치한 2개 치과의원과 1개의 치과병원에 내원한 환자 212명을 대상으로 설문조사하였으며, SPSS 14.0통계프로그램을 이용하여 분석한 결과 다음과 같은 결론을 얻었다. 1. 전체 치주조직인식정도는 3.40점으로 예방인식이 3.95점으로 가장 높게 나타났고, 관리인식은 3.09점으로 가장 낮게 나타났다. 2. 일반적 특성과 치주조직건강인식도 차이에 있어서는 성별과 직업에서 전체 치주조직건강인식도 및 각 세부영역별로 집단 간에 통계적으로 유의한 차이가 나타났다. 3. 각 세부영역별 상관관계는 예방인식과 원인인식과의 상관관계가 가장 높게 나타났고, 예방인식과 증상인식과는 상관관계가 없는 것으로 나타났다. 4. 구강보건 실천정도와 치주조직건강 인식정도의 차이에 있어 잇솔질 횟수가 많을수록 스켈링 경험이 있는 경우가 모든 영역에 있어 통계적으로 매우 유의한 차이가 나타났다.

• 한국과학교육학회지
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• 제23권1호
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• pp.21-34
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• 2003

본 연구는 현재 과학 영재 교육 프로그램에 참가하고 있는 266명의 과학 영재들을 대상으로 Sternberg(1988, 1990)의 정신자치제 이론에 기초한 사고양식 검사 도구를 사용하여 그들의 사교양식의 특성을 밝히고, 사고양식과 지능 및 창의성과의 관계를 검증하고자 하였다. 본 연구의 결과에 따르면 과학영재들은 일반 학생들 보다 자유주의적이고 입법적인 성향, 그리고 사법적인 성향을 두드러지게 나타났다. 이러한 경향은 집행적이고 보수적의적인 성향보다 창의적이고 비판적인 사고에 적합한 양식이라고 할 수 있다. 또한 사고양식은 지능검사 및 과학적 탐구능력과는 거의 관계가 없었지만, 창의성 검사와는 부분적인 상관을 보여 주었다. 즉 자유주의적인 성향이 강한 학생들은 TTCT검사의 독창성에서 높은 점수를 받았고, 유창성은 보수주의적인 경향성과 부적인 상관을 보였다. 또한 사법적인 양식은 독창성 및 융통성과 긍정적인 상관이 있었다. 본 연구를 통해서 과학 영재들의 사고양식의 경향성을 파악할 수 있었으며, 이러한 점을 고려하여 과학 영재교육에 시사점을 제공하였다.

• 아동학회지
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• 제24권3호
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• pp.135-149
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• 2003

This study aimed to develop an observation scale for assessing the quality of day care programs and to examine reliability and validity of the scale. Instruments included 3 self-assessment scales, the Evaluation Scale for Early Childhood Programs and an observation scale completed by 8 trained observers in 89 day care sites. Item analysis indicated that most items were acceptable in terms of item discrimination and item response distribution. Cronbach ${\alpha}^{\prime}s$ and inter-observer reliability were relatively high. Validity of the scale was evidenced by correlations between the observation scale and the criterion measure and inter-correlations among sub-areas of the observation scale. Scores on the observation scale were validated by quality ratings from self-assessment scores.

• 한국분무공학회지
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• 제13권3호
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• pp.117-125
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• 2008

The correlations for the prediction of maximum liquid-phase penetration in diesel spray are reviewed in this study. The existing models developed for the prediction of maximum liquid-phase penetration can be categorized as the zero-dimensional (empirical) model, the multi-dimensional model and the other model. The existing zero-dimensional model can be classified into four groups and the existing multidimensional models can be classified into three groups. The other model includes holistic hydraulic and spray model. The maximum liquid-phase penetration is mainly affected by nozzle diameter, fuel volatility, injection pressure, ambient gas pressure, ambient gas density and fuel temperature. In the case of empirical correlations incorporated with spray angle, the predicted results will be different according to the selection of correlation for spray angle. The research for the effect of boiling point temperatures on maximum liquid-phase penetration is required. In the case of multidimensional model, there exist problems of the grid and spray sub-models dependency effects.

• 아동학회지
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• 제30권6호
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• pp.549-566
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• 2009

This study developed the Place Attachment to Childhood Home Scale and evaluated its validity and reliability. Samples consisted of 418 college students of four universities. Data were collected by questionnaire based on retrospective questions about the childhood home. Factor analysis resulted in 5 dimensions of place attachment : affection, place identity, place rootedness, playfulness, and place dependence. Especially, playfulness was a unique finding. The result of confirmatory factor analysis supported the five-factor structure. There were also significant correlations among sub-factors. The reliability of the scale appeared high (Cronbach's ${\alpha}$ = .948). Criterion-related validity was confirmed by significant correlations of the present scale with Attachment Scale to Place (Hess, 1997) and the Inventory of Parent Attachment (Armsden & Greenberg, 1987).

• 한국생활과학회지
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• 제14권1호
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• pp.1-13
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• 2005

This study has a purpose of developing a scale to evaluate maternal beliefs on preschool children's education. The subjects were 307 mothers of preschool children in Gwang-ju. The methods for data analyses included a factor analysis for construct validity, Pearson correlations between beliefs and learning-related activities for construct validity, and Cronbach's a for reliability. 4 factors were found, through literature review, in parental beliefs: passive learning, active learning, instruction, and expectation for academic-related skills acquisition. Factor analysis revealed that the 4-factor solution is the best fit. Correlations between beliefs and learning-related activities were statistically significant. Cronbach's a ranged from .65 to .87 for 4 sub-scales. It was concluded that the maternal beliefs scale is acceptable for use.

• International Journal of Air-Conditioning and Refrigeration
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• 제7권
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• pp.45-54
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• 1999

In this study, condensation heat transfer experiments were conducted in two small diameter (ø17.5, ø4.0) tubes. Comparison with the existing in-tube condensation heat transfer correlations indicated that these correlations over predict the present data. For example, Akers correlation over predicted the data up to 104 %. The condensation heat transfer coefficient of the ø4.0 I.D. tube was smaller than that of the ø7.5 I.D tube; at the mass velocity of 300 kg/$m^2$s, the difference was 12 %. The pressure drop data of the small diameter tubes were highly (two to six times) over predicted by the Lockhart-Martinelli correlation. Sub-cooled forced convection heat transfer test confirmed that Gnielinski's single phase heat transfer correlation predicted the data reasonably well.

• 한국지역사회생활과학회지
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• 제20권3호
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• pp.343-355
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• 2009

The purpose of this study was to examine the efficacy of child care and the education and the influence of job-stress on job-satisfaction of child care and education teachers. 172 child care and education teachers were chosen from 40 child care centers located in Incheon, Gyeonggido, and Seoul. Data were collected using the efficacy of child care and education index, the job-stress instrument, and the job-satisfaction instrument, and were analyzed using t-test, one-way ANOVA(Duncan test), correlation analysis and multiple regression analysis. There were significant differences in child care and education teacher's job-satisfaction according to the teacher-related variables, including the type of institution, the number of classes, the age of children, the education, the teaching experience, the income, the age of teacher, and the marital status of the teacher. Correlation analysis indicated that the teacher's efficacy of child care and education and the job-satisfaction had significant correlations, especially the satisfaction of job itself indicated high positive correlations. Job-stress and job-satisfaction of the child care and education teachers had significant negative correlations in all sub-variables, especially the stress from the working environment and the satisfaction of administration system indicated high negative correlations. It was also found that stress from the working environment, stress from the overload, stress from the peer relations, and the efficacy of child care and education were all significant predictors of the child care and education teacher's job-satisfaction.

• 여성건강간호학회지
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• 제7권3호
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• pp.317-330
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• 2001

This study was undertaken in order to examine the relationship of control, perceived health status, self efficacy, social support, and demographic characteristics to health promoting lifestyle of nursing students, and to determine factors affecting health promoting lifestyle of nursing students. The subjects were 270 students of a single university in Busan. The instruments used for this study was a survey of general characteristics, health promoting lifestyle (47 items), control(8 items), perceived health status(6 items), self-efficacy(17 items), and social support(18 items). Data analysis was done by use of mean, percentage, t-test, ANOVA, Pearson Correlation coefficients and stepwise regression with a SPSS PC+ program. The results of this study are as follows : 1) The average item score for the health promoting lifestyle was less than 2.43. In the sub-categories, the highest degree of performance was interpersonal relationships (2.94) and the lowest degree was health responsibility(1.93). 2) Students who were older and higher scores in health responsibility and interpersonal support subscale. Students who had higher grade had higher scores in health support subscale. Students who had experienced disease had higher scores in health responsibility subscale. Students who had experienced exercise had higher scores in health responsibility, exercise and nutrition subscale. 3) Significant correlation between control and self-efficacy, self-efficacy and social support was found. 4) Significant correlations was found between most of the subscales and total health promoting lifestyle. 5) Social support revealed significant correlations with total health promoting lifestyle and all subscales of health promoting lifestyle. Control revealed significant correlations with total health promoting lifestyle and self actualization and health responsibility. Perceived health status revealed significant correlations only with the exercise and nutrition subscale. Self-efficacy revealed significant correlation with the total health promoting lifestyle and all subscales of health promoting lifestyle except exercise and nutrition, stress management subscale. 6) Social support was the highest factor predicting health promoting lifestyles of nursing students(31%). Social support, excercise self-efficacy and control accounted for 35% in health promoting lifestyle of nursing students.