• Journal of Technologic Dentistry
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• v.25 no.1
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• pp.71-79
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• 2003

The purpose of this study was to investigate bond strength of denture base resin repaired according to contamination. One commercial denture base resin and two different kinds of relines resin were tested; Lusiton 199(denture base resin), Vertex(reline resin) and TokusoRebase(repair resin). The specimens were processed according to the manufacturer's instructions to cured denture base resin(polymethylmethacrylate; PMMA) and reline resin. Bond strengths were examined by use of a three-point transverse flexural strength test. Data were analyzed with two-factor analysis of variance and Duncan's post-hoc test at $\alpha$=0.05. Generally, the bondstrength of heat-cured resin(Lusiton 199) was higher than the other resins. The contaminations produced an decrease in bond strength. Therefore the contamination, such as saliva or water must be avoided during the laboratory repair procedures.

• Journal of Korean Academy of Nursing
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• v.34 no.5
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• pp.751-759
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• 2004

Purpose: The aim of this study was to design and evaluate a scale for measuring the attitudes toward condom use in sexual relationships. Method: A questionnaire was administered to 631 college students using a convenience sampling method. The psychometric properties (reliability and validity) were evaluated. Result: As a result of the item analysis, 16 items were selected and the internal consistency alpha coefficient was .88. Results indicated that the condom attitude scale is composed of three factors: Interruption of sexual pleasure; Protection; and Image. The three factors accounted for 59.54% of the variance in the total scale. Also, condom attitude was statistically significant (t=7.389, p=.000) between consistent condom users and inconsistent users. Conclusion: The results demonstrate that condom attitudes are multidimensional, and the reliability and validity of the scale was supported.

• Communications for Statistical Applications and Methods
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• v.9 no.1
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• pp.141-154
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• 2002

Foreign investors'shares and their influences on the Korean stock market have never been larger and greater before since the market was completely open to foreign investors in 1992 Quantitatively and qualitatively as well, as a result, changes in the patterns of foreign investments have caused enormous effects on the interactions of major macroeconomic indices of the Korean economy. This paper is intended to investigate the causal relations of the four variables, foreigners'buy-sell ratios, stock returns, ￦/＄ exchange rates and $\yen$/＄ exchange rates, over the two time periods of the pre-IMF (1996.1.1-1997.8.15) and the post-IMF (1997.8.16-2000.6.15) based on the daily data of the variables. Granger Causality Test, Forecast Error Variance Decomposition(FEVD) using VAR model and Impulse Response Function were implemented for the empirical analysis.

• Transactions of the Korean Society of Mechanical Engineers
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• v.16 no.9
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• pp.1691-1699
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• 1992

The experimental results of fatigue crack propagation under constant amplitude loading show that intra-and inter-specimen variability exist. In this paper, a stochastic model for the estimation of mean and variance of crack propagation life is presented To take into account the intra-specimen variability, the material resistance against crack propagation is treated as an 1-dimensional spatial stochastic process, i. e. random field, varying along the propagation path. For the inter-specimen variability, C in paris equation is assumed to be a random variable. Compared with experimental results reported, the present method well estimate the variation in fatigue crack propagation life. And it is confirmed that the thicker the specimen thickness is, the less the variation of propagation life is.

• Korean Journal of Child Studies
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• v.12 no.2
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• pp.78-93
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• 1991

The purpose of this study was to develop a rating scale for measuring children's temperament. The subjects were 622(324 boys and 298 girls) 3-to 7-year-old children. The temperament rating scale was composed of 50 items(4-point Liken scales) was based on mother's interview, RITQ and PTQ. The raters were the subjects' mothers. The data were analysed on dimensions of validity, reliability, and item discrimination. Statistical methods were factor analysis, ${\chi}^2$-test, and calculations of Pearson's r Cramer's V and Cronbach's $\alpha$. On validity 5 factors were extracted, which explained 84% of the total common variance. The 5 factors were named 'malleability', 'activity', 'sensitive reactivity', 'eating habits & physical constraints', 'physiological rhythmicity'. Regarding reliability, Cronbach's $\alpha$ appeared between .66 and .81 among the 5 factors. Regarding item discrimination, the degree of discrimination on all 50 items was significant and acceptable.

• Journal of the East Asian Society of Dietary Life
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• v.19 no.1
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• pp.116-129
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• 2009

The study was conducted to evaluate consumer awareness of the risk elements associated with foods and their information search behavior regarding food safety. The data were collected from 504 adult consumers living in Seoul, Busan, Incheon, Daegu, Daejeon, and Gwangju through a self-administered questionnaire on August, 2006. Frequency analyses, t tests, one-way analysis of variance, and Duncan's multiple range comparison tests were conducted to analyze the responses using SPSS v. 14.0. The levels of recognition of consumers regarding each risk element were generally low. Many respondents answered that they obtained information regarding food safety from TV/radio/newspapers and family/relatives/friends/neighbors. The respondents also indicated that they had strong confidence in the information from family/relatives/friends/neighbors. Additionally, most respondents required information regarding heavy metal contamination, endoctrine disruptors, and avian influenza.

• Journal of Surface Science and Engineering
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• v.30 no.5
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• pp.298-309
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• 1997

Hard Tin coating on tool steel substrate were prepared using the pulsed PACVE. An orthogonal experimental design was employed to find the best deposition conditions for TiN coating and to systematically understand the effect of processing parameters. The small size Taguchi matrix called the L16 was used for experiment and ANOVA(ANalysis of VAriance) was followed to study the effect of main parameters on hardness and adhesion TiN coatings. In conclusion, pulse on/off time ratio and pulsing frequency were the major deposition parameters to determine hardness and adhesion of TiN coating in the pulsed DC PACVE process. (200) preferred orientation, columnar growth and dome-shaped surface morphology of the TiN films gave rise to a high hardness and a good adhesion to the substrates.

• Journal of Korean Academy of Nursing Administration
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• v.19 no.4
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• pp.462-469
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• 2013

Purpose: This study was performed to identify the effects of self-leadership and job involvement on clinical competence in general hospital nurses. Methods: The participants in this study were 443 staff nurses working in general hospitals and having more than 6 months of nursing experience. Data were collected using self-administered questionnaires. Results: There were significant positive correlations between nurses' self-leadership and job involvement, and between nurses' self-leadership and clinical competence. In the multiple regression analysis, clinical career, type of department and self-leadership were significant predictors in explaining nurses' clinical competence and accounted for 28% of the variance in nurses' clinical competence. Conclusion: Study findings suggest that nurses' self-leadership is defined as having an important influence on nurses' clinical competence. In order to strengthen nurses' clinical competence, there is a need to develop education programs to increase nurses' self-leadership.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2014.10a
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• pp.87-88
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• 2014

The Coastal sediment is highly contaminated due to ship transportation, industries discharges and urban sources. Various contaminants release into seawater and settle in marine sediment and it significantly affect marine eco system. In the present study evaluated the optimization of slow release biostimulant ball (BSB) in coastal sediment in busan. The effective variables like BSB size, distance and month variables on VS reduction was determined by using Response surface methodology(RSM). The analysis of variance (ANOVA) and coefficient determination (R2) of VS was 0.9369 and maximum reduction of VS was obtained in 3cm ball size and 5.5cm distance and 4 month interval time. This result revealed that the BSB in effective VS reduction in coastal sediment.

• Transactions on Electrical and Electronic Materials
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• v.7 no.6
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• pp.297-300
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• 2006

The response surface modeling of the pretilt angle control using ion-beam (IB) alignment on nitrogen doped diamond-like carbon (NDLC) thin film layer is investigated. This modeling is used to analyze the variation of the pretilt angle under various process conditions. IB exposure angle and IB exposure time are considered as input factors. The analysis of variance technique is settled to analyze the statistical significance, and effect plots are also investigated to examine the relationships between the process parameters and the response. The model can allow us to reliably predict the pretilt angle with respect to the varying process conditions.