• 설비공학논문집
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• 제8권1호
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• pp.140-150
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• 1996

CFC-12, which has been used most widely in automobile air conditioners and household refrigerators is scheduled to be phased out soon because of its high ozone depletion potential. Now HFC-134a is suggested as an alternative refrigerant for CFC-12. In this Study, we intended to investigate how PAG oil influence evaporation heat transfer and flow pattern, using R-134a and PAG oil influences evaporation heat transfer and flow pattern, using R-134a and PAG oil in the horizontal miro-fin evaporation tube. Experiments were conducted under the flowing est conditions : mass velocity 86-250kg/$m^2$s, heat flux 5-30 ㎾/$m^2$, oil concentration 0-21 wt.% and saturation temperature 5$^{\circ}C$. Local evaporation heat transfer coefficients were found to be higher at the top, side and bottom of the tube in this order. Average heat transfer coefficients turned out to increase with oil concentration increment up to 3 wt.% oil concentration, whereas heat transfer coefficients gradually decreased over 3 wt.% oil concentration, because of oil-rich liquid film was formed on the heat transfer surface. Flow patterns were rapidly transitioned to annular regimes up to 3 wt.% oil concentration. In case of pure refrigerant, measured heat transfer coefficients in the experiments were similar to those of Kandlikar＇s correlation.

• 농업생명과학연구
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• 제46권1호
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• pp.113-121
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• 2012

본 연구는 2005년에서 2009년까지 수집된 150,624개의 국내 젖소 산유능력 검정자료를 사용하여 두 가지 동기우 그룹 정의에 따른 산차, 체세포 점수가 305일로 보정된 유량, 유지방량, 유단백량, 무지고형분량에 미치는 효과와, 유량 및 유성분 간 상관관계에 변화가 나타나는가를 보고자 실시하였다. 첫 번째 동기우 그룹은 동일농장과 출생년도, 계절로 정의하였고, 두 번째는 농장과 분만년도, 계절을 동기우 그룹으로 정의하였다. 동기우 그룹을 출생년도로 구성하였을 때 동기우 그룹과 산차 및 체세포 점수가 유량과 고도의 유의성을 보였고, 유단백질량, 무지고형분량, 유지방량에 대해서도 유의적인 차이를 보였다. 동기우 그룹을 분만년도로 하였을 때에도 유량에 대한 체세포점수 및 산차 효과가 고도의 유의성을 보였고, 유단백질량, 유지방과 무지고형분량에 대해서도 고도의 유의성을 보였다. 출생년도를 사용한 모델에서 생산형질간 표현형상관을 본 결과 유량과 유단백량, 유지방, 무지고형분량은 고도의 정의 상관이 나타났으나, 유량과 체세포 점수 간에는 -0.09의 상관을 나타냈다. 분만년도를 동기우 그룹으로 사용한 모델에서의 표현형상관을 보면 유량과 유단백질 및 유지방간에 출생년도를 사용한 모델과 거의 비슷한 정의 상관을 보였고, 유량과 체세포간에는 -0.10, 유단백질, 유지방, 무지고형분량과 체세포간에는 각각 -0.08, -0.08, -0.11의 상관을 보였다.

• 대한가정학회지
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• 제33권4호
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• pp.49-64
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• 1995

The purpose of this study was to develop the Daily Hassles Scale for children in Korea. The subject were 444 children of 184 fourth graders and 260 sixth graders selected form five elementary schools in Seoul(217 male and 227 female). A questionnaire consisting of 90-item daily hassles scale, demographic questions, and some additional questions was used as a methodological instrument. statistics used for data analysis were X2, cramer's V, factor analysis, multi-regression, Pearson's r, Cronbach's α. The major findings of this study were as follows. 1) 87 items of the 90-item scale were acceptible through item discriminant method. The discriminant coefficients of the items(Cramer's V) ranged form .28 to .73. 2) 6 factors(parents, home environment, friends, studies, teachers & school, the surroundings) were extracted from factor analysis. Multi-regression analysis conducted to reduce the length of scale have drawed 42 items for 'the Daily Hassles Scale for Children in Korea'. The correlation between this scale and the Quality of Life Scale(Olson & Barnes, 1982) was conducted to test the criterion-related validity, and the coefficient was significant(r=-.52, p<.001).3) Finally, reliability coefficients(Cronbach'α) of this scale was. 85.

• 대한지역사회영양학회지
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• 제21권5호
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• pp.440-450
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• 2016

Objectives: We previously developed a dish-based semi-quantitative food frequency questionnaire (FFQ) for Korean adolescents and reported that it had reasonable reliability and validity. The objective of the current study was to construct a web-based dietary evaluation system applying the FFQ for Korean adolescents and examine its applicability in the context of reliability and validity. Methods: A web-based food frequency questionnaire system was designed using a comprehensive approach, incorporating not only dietary data survey but also up-to-date nutrition information and individualized eating behavior guidelines. A convenience sample of 50 boys and girls aged 12~18 years agreed to participate in the study and completed the FFQ twice and 3 days of dietary recall on the developed website during a two-month period. The FFQ's reliability and validity was examined using correlation and cross classification analysis. We also measured participants' subjective levels of the web site's usability, visual effect, understanding, and familiarity. Results: Spearman correlation coefficients for reliability ranged from 0.74 (for vitamin A) to 0.94 (for energy). From cross-classification analyses, the proportion of subjects in the same intake quartile was highest for energy (82.0%) and lowest for vitamin A (56.0%). With regard to validity analysis, Spearman correlation coefficients ranged from 0.34 (for fiber) to 0.79 (for energy). The proportions of subjects in the opposite categories between the first FFQ and 3-day diet recall data were generally low from 0.00% (for fat) to 36.2% (for sodium). Average subjective levels of the website's usability, visual effect, understanding, and familiarity were all found to be over 4 points out of 5 points. Conclusions: The web-based dietary evaluation system developed can serve as a valid and attractive tool for administering FFQ to Korean adolescents.

• 한국응용과학기술학회지
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• 제40권6호
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• pp.1381-1393
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• 2023

본 연구는 요양보호사의 환자안전 지식과 환자안전관리 활동의 관계에서 자기효능감의 매개 효과를 확인하기 위해 수행된 서술적 조사연구이다. 자료수집은 노인요양시설과 재가센터 소속 요양보호사를 대상으로 2022년 7월 1일부터 7월 29일까지 실시되었으며, 197명의 자료가 최종 분석에 사용되었다. 수집된 자료는 SPSS 28.0 프로그램을 이용하여 t-test, ANOVA, Scheffé test, Person's correlation coefficients, Hierarchical multiple regression으로 분석하였다. 연구결과, 요양보호사의 환자안전 지식과 자기효능감(r=.653, p<.001), 환자안전 지식과 환자안전관리 활동(r=.467, p<.001)은 각각 유의한 양의 상관관계를 보였다. 또한 요양보호사의 환자안전 지식과 환자안전관리 활동의 관계에서 자기효능감의 완전 매개효과가 확인되었고, 설명력은 46.8%였다. 따라서 요양보호사의 환자안전관리 활동을 강화하기 위해서는 자기효능감 향상을 위한 체계적인 프로그램 개발과 함께 교육의 기회가 제공되어야 할 것이다.

• Journal of Animal Science and Technology
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• 제44권5호
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• pp.523-530
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• 2002

본 연구는 1999년 8월부터 2000년 2월까지 공인 제2종돈능력검정소에서 검정 종료된 Duroc종, Landrace종 및 Yorkshire종에 대하여 체중, 등지방두께, 일당증체량 및 정육율을 측정하여, 동일 개체의 반복측정치 간의 반복력과, 상관 및 순위상관을 추정하였으며, 그 결과를 요약하면 다음과 같다. 1. 평균능력은 측정시 체중이 각각 91.0, 114.7, 123.2kg이였으며, 측정시 일령은 각각 142.1, 173.7, 182.5일이였으며, 정육율은 각각 57.9, 56.2, 55.2%였으며, 등지방두께는 각각 1.33, 1.61, 1.63cm였으며, 일당증체량은 각각 946.6, 879.2, 879.4g으로 나타났다. 2. 각 형질의 측정차수간 상관은 정육율의 경우, 1차와 2차, 1차와 3차, 2차와 3차간 각각 0.493, 0.471, 0.619로 나타났고, 등지방두께의 경우, 각각 0.424, 0.424, 0.700으로 나타났으며, 일당증체량의 경우, 각각 0.716, 0.601, 0.861로 모든 형질에서 1차와 2차간, 1차와 3차간 보다는 2차와 3차간에 높게 추정되었다. 3. 각 측정차수의 형질간 상관은 1차 측정의 경우, 정육율과 등지방두께, 정육율과 일당증체량, 등지방두께와 일당증체량이 각각 －0.597, －0.291, 0.303으로 나타났고, 2차 측정의 경우, 각각 －0.667, －0.292, 0.396으로 나타났으며, 3차 측정의 경우, 각각 －0.711, －0.369, 0.409로 정육율과 등지방두께 및 일당증체량은 부의 상관관계에 있으며, 등지방두께와 일당증체량은 정의 상관관계에 있고, 일령이 증가할수록 상관이 높게 추정되었다. 4. 각 형질의 반복력 추정치를 살펴보면, 등지방두께가 0.374, 정육율이 0.428, 일당증체량이 0.673으로 추정되었으며, 일당증체량의 반복력은 상당히 높게 추정되어, 110kg까지 검정의 필요성이 인정되지 않으나, 등지방두께와 정육율의 추정치는 낮게 추정되어 더욱 많은 연구가 필요할 것으로 사료된다.

• The Korean Journal of Physiology
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• 제4권2호
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• pp.37-44
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• 1970

Human body volumes were calculated from the measurments of body height and body weight. Equations Suited to express the relations of height, weight, and surface area to show the body volume were derived from the body volume measurements by means of underwater. weighing method. Underwater body weights were corrected for the residual volume of long obtained by the Rahn's three breath method. Underwater weighing was performed on 173 male subjects aged between 13 and 51 years. Subjects were divided into 4 age groups, namely, 13-16 years group of 47 subjects, 16-19 years group of 46 subjects, adult group aged between 22 and 38 years comprising 45 subjects, and middle-aged group (40-51 years) of 35 subjects. The group division was made on .the basis of physical growth and development. The following results were obtained. 1. Body height (H, cm), body weight (W, kg), body surface area $S,\; m^{2})$, and body volume (V, liter.) interrelated closely. V/S showed a high correlation with W/H and the coefficient of correlation was r=0.97 irrespective of age group differences of the subjects. The coefficients of correlation between V/S and W/H in the total mate subjects as a single group was r=1.983. Subsequently the following regression equation was obtained. V = S X (54.84 W/H + 14.08) The agreement of body volume values obtained by the calculation and underwater weighing in the total subject group was better than that of the separate age group division. 2. The calculated values of body volume were: 40.4 l (euiqvalent to the body density value of 1.0562 kg/1) in 13-16 years group; 52.0 l (equivalent to density value of 1.0723 kg/l) in 16-19 years group; 55.3 l (equivalent to density value of 1.0570 kg/l) In the adult group; and 54. 0 l (equivalent to density value of 1.074 kg/l) in the middle-age group. The mean deviation of calculated from the measured volume value ranged between ${\pm}0.55$ and ${\pm}0.81$ liters. 3. The correlation between V/S and mean skinfold thickness of 4 sites (arm, back, iliac and chest) was high, namely, the coefficient of correlation was r=0.656. The coefficients of correlation between V./S and the $R\"{o}hrer$ index ranged between r=0.668 and r=0.810 affected by the difference in group age of the subject. The body volume (V) alone correlated poorly than V/S with mean skinfold thickness (r=0.606) and the $R\"{o}hrer$ index (r ranged between 0.274 and 0.588).

• 한국지역사회생활과학회지
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• 제27권1호
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• pp.5-17
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• 2016

The purpose of this study was to examine the mediating effects of young children's shyness on the relationship between teacher-children relationship and young children's social competence. The subjects of the study were 270 children from three years to five years old and their teachers in Busan. Frequency, t-test, Cronbach ${\alpha}$, Pearson's correlation coefficients, and hierarchial regression were used for data analysis. The results were as follows: first, teacher-children intimacy showed positive correlation with the young children's social competence. Teacher-children conflict showed negative correlation with the young children's social competence. Second, teacher-children intimacy showed negative correlation with the young children's shyness. Teacher-children conflict showed positive correlation with the young children's shyness. Third, young children's shyness showed negative correlation with the young children's social competence. Fourth, young children's shyness had partial mediating effects on the relationship between teacher-children intimacy and young children's sociability. Young children's shyness had partial mediating effects on the relationship between teacher-children intimacy and young children's popularity and leadership. Young children's shyness had partial mediating effects on the relationship between teacher- children conflict and young children's sociability. Young children's shyness had partial mediating effects on the relationship between teacher-children conflict and young children's popularity and leadership.

• 대한가정학회지
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• 제24권1호
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• pp.129-138
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• 1986

The purpose of this study is to investigate the child's preference attitude for one parent and to analyze the difference in the four variables(sex, age, birth order and maternal employment) and the factors influencing it. To meet this purpose, three kinds of questionnaire for child (school-age/late adolescence) and his parents were used. The data were obtained through 136 pairs(parents and child) and analyzed by chisquare test and Guttman's lambda. The results of this test are summerized as follows. 1. The majority of children prefer mother to father and especially adolescent daughters prefer mother more than sons. 2. The majority of parents answered that their child would prefer mother to father and the correlation coefficient between mother's answer and fathers is .53. But child's actual preference is no related with parent's awareness of being preferred. 3. The majority of parent's answer were consistent with child's preference but the correlation coefficients are very low from the analysis of factors influencing the child's preference. Therefore parents and child must have more communication, concern and expression of love for mutual consistence.

• 대한간호학회지
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• 제33권5호
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• pp.609-617
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• 2003

Purpose: The purpose of this study is to understand the depression of patients for Fibromyalgia Syndrome(FMS) and to identify the factors influencing depression. Method: The instruments used here are Beck Depression Inventory in depression, the Korean Rheumatology Health Association' instruments in Self-Efficacy. Also, Pain and Fatigue was measured by Visual Graphic Rating Scale. The subject of study is 76 outpatients diagnosing FMS from rheumatism specialists at C hospital in D city. The data has been collected from Sep. 1st to Sep. 30th in 2001. For the analysis of collected data, frequency analysis, independent t-test, analysis of variance, Pearson's correlation and multiple regression analysis were used for statistical analysis with SAS statistical program. Result: General characteristics showing statistically significant difference in depression were age, education, occupation, gender, exercise and sleep in the patients with FMS. Depression for the patients with FMS has negative correlation coefficients with Self-efficacy and ADL, and positive correlation coefficients with Pain and Fatigue. The suitable regression form resulting from the multiple regression analysis to investigate the influencing factors of depression for the partients with FMS was expressed by y =50.067 - 0.278x$_1$ + 1.320x$_2$ (x$_1$: Self-Efficacy x$_2$: Fatigue) and $R^2$ =0.427. Conclusion: The factors influencing on depression of patients for FMS was Self-Efficacy, ADL, Pain, and Fatigue. Further study needs to be done identify methods of overcoming and presentation of depression in FMS.