• The Journal of Korean Academy of Prosthodontics
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• v.49 no.1
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• pp.73-79
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• 2011

Purpose: The aim of this study was to evaluate the effect of repeated firings on the color of zirconia restoration with different shading method. Materials and methods: Three different types of zirconia frameworks (adding metallic pigments to the initial zirconia powder before sintering (Group NM), dipping the milled frameworks in dissolved coloring agents (Group KI), or application of liner material to the sintered white frameworks (Group KW) were used to support A3 shade dentin porcelain. Repeated firings (3, 5, or 7) were performed, color differences among ceramic specimens were measured using a colorimeter. Repeated measurements analysis of variance (ANOVA) was used to analyze the data for significant difference. The Tukey Honestly Significant Different (HSD) test was used to perform multiple comparisons (${\alpha}$ = .05). Results: 1. $L^*a^*b^*$ values of the ceramic systems were affected by the number of firings (1, 3, 5 or 7 firings) (P < .001) and shading methods (P < .001). 2. As the number of firings increased, the $L^*$ (for all groups) and $a^*$ value (for KW and NM groups) decreased and the $b^*$ value(for all groups) increased. 3. The mean color differences caused by repeated firings were perceptible (${\Delta}E$ > 1) for group KW and KI fired after 3 times, except for group NM fired after 7 times. 4. In order of decreasing ${\Delta}E$ value fired after 7 times, the values were group KI(${\Delta}E$ = 2.26) > group KW (${\Delta}E$ = 1.47) > group NM (${\Delta}E$ = 1.08) (P < .001). Conclusion: Repeated firings influenced the color of the zirconium-oxide all-ceramic specimens with different shading methods.

• Journal of applied mathematics & informatics
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• v.25 no.1_2
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• pp.389-405
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• 2007

In this paper, we study a k-out-of-n system with single server who provides service to external customers also. The system consists of two parts:(i) a main queue consisting of customers (failed components of the k-out-of-n system) and (ii) a pool (of finite capacity M) of external customers together with an orbit for external customers who find the pool full. An external customer who finds the pool full on arrival, joins the orbit with probability ${\gamma}$ and with probability $1-{\gamma}$ leaves the system forever. An orbital customer, who finds the pool full, at an epoch of repeated attempt, returns to orbit with probability ${\delta}\;(<\;1)$ and with probability $1-{\delta}$ leaves the system forever. We compute the steady state system size probability. Several performance measures are computed, numerical illustrations are provided.

• The Journal of the Korean dental association
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• v.52 no.9
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• pp.558-569
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• 2014

Sample size determination is critical, but not easy to do. Sample size defined as the number of observations in a sample to be studied should be big enough to have a high likelihood of detecting a true difference between groups. Practical procedure for determining sample size, using $G^*$power and previous dental articles, was shown in this study. Examples involving independent t-test, paired t-test, one-way analysis of variance(ANOVA), and one-way repeated-measures(RM) ANOVA were used. The purpose of this study is to enable researchers with non-statistical backgrounds to use in practice freely available statistical software G*power to determine sample size and power.

• Korean Journal of Child Studies
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• v.29 no.6
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• pp.177-191
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• 2008

Prior studies were limited in the comparison of false belief tasks with desire tasks due to lack of consideration of level of executive functions. To compensate for this, executive functions were included in new preference-related and game-related tasks of conflicting desire. These tasks were administered to 246 preschoolers ranging from 2.5 to 4 years of age. Statistical analysis was by one-way ANOVA and repeated measures ANOVA. Results showed significant main effects depending on age and task type. Younger children lacked ability of executive function, such as inhibition and working memory. Older preschoolers averaged better scores on task performance, showing that it is difficult for younger children to control their own desires and select the contradicted view.

• Journal of Korean Academy of Nursing
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• v.35 no.1
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• pp.135-142
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• 2005

Purpose: This study was aimed at developing an efficient nursing method for the management of constipation by comparing the effects of abdominal meridian massage on the symptoms of constipation. Method: The subjects were determined by the Rome II criteria and the Constipation Assessment Scale from Aug 30 through Sep 26, 2002. They were randomly divided into two groups: one experimental group of 16, another control group of 15. Abdominal meridian massage was given to the experimental group and no massage was given to the control group. The frequency of defecation and severity of constipation by CAS were measured. The data was analyzed with the t-test, $x^2$-test, and repeated measures ANOVA. Results: There was a significant improvement in frequency of defecation, and severity of constipation in the experimental group compared to the control group. Conclusion: Abdominal meridian massage can be considered an effective nursing method for the management of constipation among CVA patients.

• Korean Journal of Child Studies
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• v.12 no.1
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• pp.21-37
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• 1991

The present research studied the effectiveness of specific strategy training in memory awareness on children's memory performance. The subjects were 60 children, 30 six-year-olds and 30 eight-year-olds. Free recall scores and use of a rehearsal strategy (exposure durations) based on Belmont & Butterfield (1971) were used to measure children's performance in three memory tasks. All subjects were randomly assigned to one of three experimental groups: the control group with no training, the chunking and rehearsal strategy training group, and the chunking and rehearsal strategy training combined with memory awareness strategy. The data were analyzed with two-way ANOVA, three-way ANOVA with repeated measures, and Student-Newman-Keuls post hoc test. There were significant differences among the three groups both in the free recall score and in the use of the rehearsal strategy. The mnemonic strategic training with memory awareness strategy was the most effective on both free recall and use of rehearsal strategy. The effects of the mnemonic strategy training with memory awareness strategy were more effective for the 8-year-olds than the 6-year-olds.

• Transactions of Materials Processing
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• v.14 no.4 s.76
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• pp.360-367
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• 2005

The injection-molded plastic parts have many surface defects: warpage, weldline, flowmark, zetting, scratching, shading and so on. As weldline was one of the major surface defects in the case of desktop monitor, warpage and surface shrinkage are the bigger problems of LCD monitor in the pursuit of light weight and thinner thickness of parts. Some measures to improve these defects were introduced in this paper. Based on these, the laboratory work to find out the optimum processing conditions and to get the best parts was repeated injection moulding try-out after reflecting these improvements. The defects of warpage and surface shrinkage was significantly improved after the improvements in the case of the 20.1 inch even if in the 15 and 17inch case the warpage size was a lttle over the allowed specification because of not taking the measure for parts design within the allowable limits from the required specification in the cause of cost down.

• Journal of Korean Biological Nursing Science
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• v.12 no.1
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• pp.24-30
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• 2010

Purpose: This study was aimed to identify the effects of Self-Foot Reflexotherapy on the Fatigue, Mood and Vital Signs of the Nursing students. Methods: The research design was a quasi experimental, one-group pretest-posttest design. The data were collected from June 15 to August 31, 2008. The one group was consisted of 21 subjects. The instruments used for the study were the Fatigue and Paleasant mood. The data were analyzed by SPSS WIN 12.0 program. In order to compare the effect of the pre-post Foot Reflexotherapy, paired-test and Repeated Measures ANOVA was employed. Results: A significant decrease in fatigue, increase in Mood and Vital signs after providing self foot reflexotherapy was observed. Conclusion: The result suggests that a self foot reflexotherapy could be utilized as an effective nursing intervention to the patients to reduce fatigue, Mood and vital signs.

• Communications for Statistical Applications and Methods
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• v.5 no.2
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• pp.491-501
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• 1998

Motivated by bioequivalence studies which involve comparisons of pharmaceutically equivalent dosage forms, we propose a more general decision rule for showing equivalence simultaneously between multiple means and a control mean. Namely, this testing procedure is concerned with the situation in that one must make decisions as to the bioequivalence of an original drug product and several generic formulations of that drug. This general test is developed by considering a spherical confidence region, which is a direct extension of the usual t-based confidence interval rule formally approved by the U.S. Food and Drug Administration. We characterize the test by the probability of rejection curves and assess its performance via Monte-Carlo simulation. Since the manufacturer's main concern is the proper choice of sample sizes, we provide optimal sample sizes from the Monte-Carlo simulation results. We also consider an application of the generalized equivalence test to a repeated measures design.

• Korean Journal of Child Studies
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• v.20 no.3
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• pp.231-244
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• 1999

This study examined the effects of short and long term playing of video gamer on children's visual parallel processing. All of the 64 fourth grade subjects were above average in IQ. They were classified into high and low video game users. Instruments were a visual parallel processing task consisting of imagery integration items, computers, and the arcade video game, Pac-Man. Subjects were pre-tested with a visual parallel processing task. After one week, the experimental group played video games for 15 minutes, but the control group didn't play. Immediately following this, all children were post-tested by the same task used on the pretest. The data was analyzed by ANCOVA and repeated measures ANOVA. The results showed that relaying short-term video games improved visual parallel processing and that long term experience with video games also affected visual parallel processing. there were no differences between high and low users in visual parallel processing after playing short term video games.