• Title/Summary/Keyword: T-test analysis

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The Improvement and Diagnosis of DC Degradation Properties with The Equivalent-Circuit Analysis of ZnO Varistors (ZnO 바리스터의 등가회로 분석을 통한 DC 열화특성의 향상과 진단)

  • So, Soon-Jin;Kim, Deok-Kyu;Kim, Young-Jin;So, Byung-Moon;Park, Choon-Bae
    • Proceedings of the KIEE Conference
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    • 1999.11d
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    • pp.978-980
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    • 1999
  • In this paper, DC degradation of ZnO varistor sintered in the atmospheres of nitrogen and oxygen was investigated. The content of $SiO_2$ containing 0.0, 0.2, 0.5 mol% respectively was addicted for the improvement of degradation property. ZnO varistor was fabricated in the special electrical furnace which had the vacuum system. The temperature and the voltage for the DC degradation test were $115{\pm}2^{\circ}C$, $0.85V_{1mA/cm^2}$. The time conditions for this test were 0, 2, 4, 8 hours and Current-voltage analysis is used to determine nonlinear coefficients($\alpha$). Frequency analysis are accomplished for the understanding of electrical properties as DC degradation test. In this experiment, We concluded that nonlinear coefficient decreased as the amount of $SiO_2$ addition increased, but degradation rate coefficient increased as the amount of $SiO_2$ addition increased. Also, degradation test with the analysis of equivalent circuit showed that the degradation phenomenon of ZnO varistor wasn't linearity.

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Analysis on the increasing loss in Temperature rise test of induction motor by equivalent load method (등가부하법에 따른 유도기 온도상승 시험시 발생 증분 손실 해석)

  • Park, J.T.;Lee, J.I.;Kim, K.O.;Kwon, J.L.;Kwon, B.H.
    • Proceedings of the KIEE Conference
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    • 2007.07a
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    • pp.1045-1046
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    • 2007
  • As equivalent load method of induction motor, even without connecting load, for temperature rise test has been acknowledged economic and corrective method, the method has been widely used instead of the real load method, and also international standards IEC 61986 is published in 2002. ABB, an well-known and famous electric machinery maker in the world, has been already applying the equivalent load method since 2002. HHI has been using real load method and equivalent load method for temperature rise of induction motor, it is already known that the equivalent test results is higher as $1-5^{\circ}K$ than that of real load test. But, quantity analysis for the reason of the temperature rise is not satisfied sufficiently. So, in this paper, quality analysis and also quantity analysis was conducted.

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Effectiveness of Public Health Center Smoking Cessation Counseling Program using the Transtheoretical Model (범이론적 모형을 적용한 대면적 금연상담 프로그램의 효과)

  • Kim, Yun-Hee;Kim, Jung-Soon;Kim, Myoung-Soo
    • Journal of Korean Academy of Nursing
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    • v.39 no.4
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    • pp.469-479
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    • 2009
  • Purpose: The purpose of this study was to identify the effectiveness of public health center smoking cessation counseling program using the transtheoretical model on the process of change, smoking temptation, decisional balance and stage change transition. Methods: A nonequivalent control group non-synchronized design was used for this study. The study population was 115 adult smokers. The counseling program was administered to the experimental group and a smoking cessation program from the Korean Ministry of Health & Welfare was administered to the control group. Descriptive analysis, $\chi^2-test$, t-test, and ANCOVA were used with the SPSS 12.0 program to analyze the data. Results: After treatment with this program, the experimental group showed significantly higher scores for process of change (t=4.148, p<.001), smoking temptation (t=-2.988, p=.003), and stage change transition ($\chi^2=5.871$, p=.031) compared to the control group. Experimental group members also showed significantly lower score for Pros of smoking (t=-3.151, p=.002). Conclusion: The findings indicate that this program could have positive effect on process of change, smoking temptation, decisional balance and stage transition for adult smokers. Based on these findings, the authors suggest additional counseling program focusing on smokers in specific stages.

Moderation and Mediation Effects of Self-efficacy and Perceived Behavioral Control on the Relationship between Knowledge of and Compliance with Handwashing in Nursing Students (간호대학생의 손씻기 지식과 수행의 관계에서 자기효능감과 지각된 행위통제의 조절 및 매개효과)

  • Park, Soonjoo
    • Journal of Korean Academy of Fundamentals of Nursing
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    • v.24 no.3
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    • pp.219-229
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    • 2017
  • Purpose: The aim of this study was to examine the relationship between handwashing knowledge and handwashing compliance in nursing students and to identify the moderation and mediation effects of self-efficacy and perceived behavioral control on the relationship. Methods: The participants were 172 nursing college students who completed the self-report measures. Data were analyzed using t-test, ANOVA, and Pearson correlation coefficient, Multiple regression analysis was used to test moderation and mediation effects. Results: The score for knowledge of handwashing was higher in participants who had completed fundamentals of nursing practicum (t=-6.54, p<.001) and the score for compliance with handwashing was higher in participants who had completed clinical practicum (t=-3.81, p<.001) or fundamentals of nursing practicum (t=-5.97, p<.001). Self-efficacy showed a significant moderation effect (z=2.21, p=.027) but not a mediation effect while perceived behavioral control had a significant mediation effect but not a moderation effect on the relationship between knowledge of handwashing and compliance. Conclusion: Findings indicate that clinical practicum and fundamentals of nursing practicum were helpful to nursing students in acquiring knowledge and in practicing proper handwashing technique. These findings suggest that continuing and repetitive education programs on handwashing need to be enhanced and strategies to strengthen self-efficacy and perceived behavioral control need to be included in education programs.

Impact of Maternal Uncertainty on Coping: Experiences from a General Hospital Pediatric Ward (입원 환아 어머니의 불확실성이 대처에 미치는 영향: 일 개 종합병원 소아과병동을 중심으로)

  • Lee, Sun Ok;Kim, Moon Jeong
    • Child Health Nursing Research
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    • v.24 no.4
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    • pp.364-372
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    • 2018
  • Purpose: The aim of this study was to test whether maternal uncertainty and the general characteristics of mothers and children influenced maternal coping. Methods: In this cross-sectional study, 190 mothers whose children had been admitted to the pediatric ward of a general hospital completed self-report questionnaires during their children's hospitalization. The questionnaires assessed the general characteristics of the mothers and children, maternal uncertainty, and maternal coping. Multiple regression analysis was used to test the research model. Results: In the multivariable model, help from one's spouse (t=3.10, p=.002), religion (t=2.68, p=.008), overall ambiguity (t=2.64, p=.009), and family income (t=2.33, p=.021) were associated with higher coping scores. Conclusion: This research model presents possible guidelines for pediatric nurses to provide comprehensive and accurate information on children's illnesses and treatments for mothers of children hospitalized in general hospitals. In particular, nurses should pay more attention to mothers who are not receiving help from their spouses, are not religious, and have a low family income.

Effects of a Community-based Follow-up Program for Parents with Premature Infants on Parenting Stress, Parenting Efficacy, and Coping

  • Ji, Eun Sun;Shim, Ka Ka
    • Child Health Nursing Research
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    • v.26 no.3
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    • pp.366-375
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    • 2020
  • Purpose: This study was conducted to evaluate the efficacy of a community-based follow-up program on parenting stress, parenting efficacy, and coping among parents with premature infants. Methods: A non-equivalent control group pre-post quasi-experimental design was used. This program consisted of structured home visits and self-help group meetings for 6 months. The experimental group (n=29) received visits by an experienced neonatal intensive care unit (NICU) nurse and the control group (n=27) was visited by a visiting nurse. Data were analyzed using the χ2 test, t-test, and analysis of covariance. Results: Parents' coping behavior significantly differed in the experimental group compared to the control group (t=3.14, p=.003). In particular, coping subscale I, for maintaining the family situation (t=2.63, p=.011), and subscale III, for understanding the infant's medical situation (t=4.30, p<.001), showed significant differences in the experimental group. There were no significant between-group differences in parenting stress or parenting efficacy. Conclusion: The findings of this study suggest that home visits by an experienced NICU nurse provided through a community-based follow-up program were an effective intervention to improve coping behavior among parents with premature infants.

A Study on Clothing Satisfaction of the Ready to Wear Garment for Women - focused on over 165cm in height- (여성기성복 소비자의 의복만족도에 관한연구 -신장 165cm 이상의 여대생 중심으로-)

  • 이선명
    • Journal of the Korean Society of Costume
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    • v.35
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    • pp.167-180
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    • 1997
  • The purpose of this study was to find out some of the problems consumers have with ready to wear garments sizing and clothing satisfaction the following women's garments; sweaters T-shirts blouses jackets pants skirts one-piece jumpers and burberry(coats). For this study questionnaires were administered to female students in community college. Employing a sample of 166 students data were analyzed by Frequencies X2-test t-test ANOVA Factor Analysis and Regression. Major results of this study were summerized as follows: 1) Purchasing clothing subjects considered mainly bust circumference for T-shirts and blouse shoulder width for jackets and jumpers hip circumference for pants and skirts and length for sweaters(knit) one-piece and burberry(coats) as a reference of fitting sites. 2) In relation with dissatisfaction with apparel fit hip circumference of pants including jeans was found as the most unsatisfactory site. Besides subjects were dissatisfied with skirts sweaters one-piece jackets blouses burberry(coats) jumpers T-shirts in order. In relateion with height and body type were most dissatisfied with pants(jeans) 3) Factors related to clothing deprivation of ready-to-wear garment were identified as aethetics elements practical elements economic elements and fittness elements. Fittness elements were most dissatisfied factors with all items of garments except for skirts.

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The comparison of the appearance perception, satisfaction, and self-esteem following the adolescent orthodontic treatment demand (청소년의 교정치료 희망여부에 따른 외모인식도와 외모 만족도 및 자아존중감 비교)

  • Lee, Kyung Hee;Lee, Hea Shoon
    • Journal of Korean society of Dental Hygiene
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    • v.13 no.6
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    • pp.1063-1070
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    • 2013
  • Objectives : The purpose of the study is to investigate the relationship between appearance perception, appearance satisfaction, and self-esteem in adolescents who demand the orthodontic treatment. Methods : A total sample of 403 high school students filled out the questionnaire and data were analyzed by using SPSS ver 20.0. for n (%), chi-square test, t-test, and a logistic regression. Results : Girl students (68.3%) tended to have a higher demand for orthodontic treatment than male students (31.7%). Higher appearance perception(t=6.967, p<0.001), lower appearance satisfaction(t=-5.477, p<0.001) and lower self-esteem(t=-7.333, p<0.001) were higher in group of demand for orthodontic treatment. The logistic regression analysis revealed that a gender, self-perception of their teeth, appearance perception, and self-esteem were significantly associated with orthodontic treatment demand. Conclusions : The result of this study will provide basic data for the consideration of psychosocial factors in orthodontic treatment in adolescents.

Analysis of Recognition Difference Regarding Informatics Textbook (정보 교과서에 대한 인식 차이의 분석)

  • Kang, Oh-Han
    • Journal of Korea Society of Industrial Information Systems
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    • v.16 no.2
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    • pp.191-198
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    • 2011
  • In this paper, we examine the different viewpoints of teachers and undergraduates on middle school informatics textbook. For this research, a survey is conducted on middle school informatics teachers and undergraduates who are preparing the state examination for informatics-computer teachers. Items of the survey were chosen to investigate the level of completion on the contents and structure of the textbook and to examine overall satisfaction with the textbook. Seven items concerning the level of completion are based on national textbook authorization criteria. A t-test was performed to analyze meaningful difference in perception of textbook between the teacher and student groups. The result shows there is meaningful difference on two items which are 'compliance with informatics curriculum' and 'content selection and organization'.

Effects of a Cognition Activation Program for the Institutionalized Old-Old in Korea (장기요양서비스 수급 후기노인의 인지향상 프로그램 중재 효과)

  • Lee, Hung Sa;Lee, Dohyun
    • Research in Community and Public Health Nursing
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    • v.24 no.4
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    • pp.427-437
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    • 2013
  • Purpose: This study was conducted to test effects of a cognition activation program on ADL, cognitive functions, depression, and QOL in the institutionalized elderly. Methods: The subjects were 40 elders who were admitted to a nursing home, with 20 of them in the experimental group and the other 20 in the control group. Data were collected from September 1 to December 17, 2012. The experimental group participated in a 12 week intervention program. ADL, cognitive functions, depression, and QOL were measured before and after the intervention. Data were analyzed by t-test and regression analysis of the SPSS and AMOS programs. Results: ADL (t=2.468, p=.017), depression (t=-2.625, p=012), and QOL (t=2.428, p=.020) were more significantly improved in the experimental group than in the control group, but there were no statistical differences in cognitive function between the two groups. Cognitive functions had positive effects on ADL (CR=-2.263, p=.024) and depression affected QOL (CR=-7.248, p<.001). Conclusion: The intervention program had positive effects on ADL, depression, and QOL except cognition. Cognitive functions of elders dramatically decrease after age 85, and it takes too much time to improve it. Therefore the program for the improvement of cognitive functions should be provided as early as possible.