• Ocean and Polar Research
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• 제36권4호
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• pp.327-341
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• 2014

This study aims to analyze causality among Wando abalone producer prices by size using a vector autoregressive model to expiscate the leading-price of Wando abalone in various price classes by size per kg. This study, using an analytical approach, applies a unit-root test for stability of data, a Granger causality test to learn about interaction among price classes by size for Wando abalone, and a vector autoregressive model to estimate the statistical impact among t-1 variables used in the model. As a result of our leading-price analysis of Wando abalone producer prices by shell size using a VAR model, first, DF, PP, and KPSS tests showed that the Wando abalone monthly price change rate by size differentiated by logarithm were stable. Second, the Granger causality relationship analysis showed that the price change rate for big size abalone weakly led the price change rate for the small and medium sizes of abalone. Third, the vector autoregressive model showed that three price change rates of t-1 period variables statistically, significantly impacted price change rates of own size and other sizes in t period. Fourth, the impulse response analysis indicated that the impulse responses of structural shocks for price change rate for big size abalone was relatively more powerful in its own size and in other sizes than shocks emanating from other sizes. Fifth, the variance decomposition analysis indicated that the price change rate for big size abalone was relatively more influential than the price change rates for medium and small size abalone.

• 한국지형학회지
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• 제27권2호
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• pp.19-28
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• 2020

Grain size analysis is the most basic procedure for identifying the origin, transport and sedimentation processes of sediments, and is widely used in geomorphology and sedimentology. Traditionally, grain size was determined by a sieve-pippette method, but the use of automated analyzers is increasing in recent years. These analyzers have many advantages over traditional techniques, but the measurement results are not always the same. It is still difficult to solve the pretreatment problem such as incomplete diffusion and residual organic matter, and inappropriate results may be obtained. This study compared image-based grain size analysis and sieve analysis to verify its statistical reliability, and conducted experiments to enhance the measurement accuracy using shape parameters. The results showed that the image-based analysis overestimated the grain size of sand dunes by about 7% compared to the sieve analysis, but the two measurements were not statistically different. In addition, by using shape parameters, such as aspect ratio, sphericity, and convexity, improved statistics were obtained compared to the original data. Using the morphological properties of the individual grains is a complementary method to the incomplete pretreatment of the grain size analysis process, and at the same time, it will contribute to improving the accuracy and reliability of the results.

• 한국융합학회논문지
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• 제7권5호
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• pp.145-153
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• 2016

이 연구는 메타분석을 활용하여 현재 다양한 영역에서 실시되고 있는 수용전념치료 프로그램의 효과에 대해 종합적으로 평가하였다. 메타분석은 통계적인 방법을 활용하여 개입의 크기와 방향을 제시한다. 이를 통해 개입에 대한 종합적 분석이 가능하다. 논문의 선정기준을 통해 총 43편의 연구물을 분석 대상으로 선정하였다. 선정된 33편의 연구물에서 183개의 효과크기를 종합하여 전체효과크기, 하위집단별 효과크기, 메타회귀분석 결과를 제시하였다. 그 결과 수용전념치료 프로그램의 전체 효과크기는 0.704로 나타났다. 이는 중간 이상의 효과크기를 의미한다. 수용전념치료의 효과 영역에 따라 효과크기를 비교한 결과, 정의적 영역, 인지적 영역, 행동적 영역 순으로 효과크기를 나타냈다. 참가자의 특성에 따른 효과크기를 비교한 결과 첫째, 성별에 따른 분석결과, 혼성 집단, 여성 집단, 남성 집단 순으로 효과크기를 나타냈다. 둘째 연령에 따른 분석 결과 일반성인, 대학생(대학원생), 청소년 순이었다. 이러한 연구 결과를 바탕으로 후속연구와 향후 프로그램 운영에 대한 시사점을 논의하였다.

• 농촌지도와개발
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• 제29권4호
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• pp.225-250
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• 2022

This study aims to examine the effects of infant's social development forest experience activities through meta-analysis. The final nine studies(total of 165 in the experimental group and 159 in the control group) were selected as a method of systematic review. Meta-analysis on overall effect size estimation, chi-square test, significance analysis, publication bias analysis, and subgroup analysis was performed using the R program. The overall effect size of 9 studies was 1.59, indicating a large effect size. As a result of subgroup analysis of the sub-factors of sociality, autonomy showed the largest effect size at 1.47, the adjusted effect size of cooperation was 1.34, the effect size adjusted for peer interaction was 1.29, and the adjusted effect size for perspective-taking ability was 0.97. All were found to have a statistically significant effect. To analyze the moderating effect, a meta-regression analysis was conducted on the participation period(4, 5~6, 7~8weeks), the number of sessions(6~10, 11~15, 16~20), the frequency per week(1, 2, 5), and the participation time(40, 60, 90, 120, 150min), but there was no statistical difference. Although not statistically significant, the effect size was larger when the participation period was 4 weeks, the number of sessions was 16 to 20, the frequency was 2 times per week, and the participation time was 40 minutes. This results can be usefully utilized by policy makers and forest commentators related to the vitalization of forest education through forest experience activities.

• 복식문화연구
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• 제8권6호
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• pp.930-939
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• 2000

This study was done to provide the fundamental data for scientific and rational children's clothing sizing system by investigating their somatometric characteristics and classifying somatotypes. The subjects were 269 elementary schoolgirls aged from 7 to 8 years old living in Pusan and Kyungsangnam-do. Data from each girl comprises 28 anthropometic measurments and 4 photographic measurments, related to the lower half of body. To analyze somatotypes of the lower half of body, factor analysis, cluster analysis, discriminant analysis were performed for statistical analysis of the data. As to the analysis to draw somatometric factors by this age group, five factors which explain 76.85% of the whole variances were extracted. The first and second factors which explain more than 60% of the whole variances represent 'horizontal size'and 'vertical size', which characterize most aspects of the body shape of the subjects. On the basis of the cluster analysis, three different lower half of body types were categorized. Type Ⅰ has biggest horizontal size, average vertical size and most protruded belly. Type Ⅱ has average degree of horizontal size, quite big vertical size and most protruded hips. Type Ⅲ has smallest horizontal and vertical size. According to the analysis to discriminate somatotypes of the lower half of body of this age group, weight and waist circumference of discriminant function 1 and abdominal circumference of discriminant function 2 have coefficient values.

• Journal of Mechanical Science and Technology
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• 제14권4호
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• pp.401-407
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• 2000

An elastic-plastic finite element analysis is performed to investigate detailed closure behavior of fatigue cracks and the numerical results are compared with experimental results. The finite element analysis performed under plane stress using 4-node isoparametric elements can predict fatigue crack closure behavior. The mesh of constant element size along crack surface can not predict the opening level of fatigue crack. The crack opening level for the constant mesh size increases linearly from initial crack growth. The crack opening level for variable mesh size, is almost flat after crack tip has passed the monotonic plastic zone. The prediction of crack opening level using the variable mesh size proportioning the reversed plastic zone size with the opening stress intensity factors presents a good agreement with the experimental data regardless of stress ratios.

• 한국간호교육학회지
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• 제21권3호
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• pp.308-319
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• 2015

Purpose: The purpose of this study was to identify the effects size of simulation education targeting korean nurses and nursing students. Methods: Meta-analysis was conducted with 48 papers in domestic master and doctorate degree dissertations and academic journals from 2000 to 2014. Results: The entire effect size in simulation education was relevant to big effect size. Regarding the effect size of individual variables, nurse was identified to have biggest effect size in study subject, standardized patient was identified to have biggest effect size in simulation methods and pediatric nursing was identified to have biggest effect size in study subjects. Effect size in each effect variable was highest in psychomotor domain. Conclusion: This study identified the effect size of simulation education and provided the basic data to contribute to the quality improvement of simulation education which is based on the reasons.

• 대한간호학회지
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• 제45권5호
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• pp.641-649
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• 2015

Purpose: The purpose of this study was to introduce the main concepts of statistical testing and effect size and to provide researchers in nursing science with guidance on how to calculate the effect size for the statistical analysis methods mainly used in nursing. Methods: For t-test, analysis of variance, correlation analysis, regression analysis which are used frequently in nursing research, the generally accepted definitions of the effect size were explained. Results: Some formulae for calculating the effect size are described with several examples in nursing research. Furthermore, the authors present the required minimum sample size for each example utilizing G*Power 3 software that is the most widely used program for calculating sample size. Conclusion: It is noted that statistical significance testing and effect size measurement serve different purposes, and the reliance on only one side may be misleading. Some practical guidelines are recommended for combining statistical significance testing and effect size measure in order to make more balanced decisions in quantitative analyses.

• 대한통합의학회지
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• 제6권2호
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• pp.1-16
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• 2018

Purpose : This meta-analysis was aimed at guiding future research in stroke treatment and to provide real-world data relating to the effects of aquatic exercise therapy on balance in patients with chronic stroke. Methods : We performed a meta-analysis comprising 22 studies involving aquatic exercise therapy performed between 2006 and 2017. A meta-analysis software program was used to calculate the mean effect size, effect size by intervention, and effect size by outcome. We also performed a meta-regression analysis and an analysis of publishing bias. Results : The mean effect size was 0.563. The effect size by outcome was observed to be the largest for the functional reach test, followed by the Berg balance scale, balance equipment, the Timed Up and Go test and one leg standing. Meta-regression analysis showed that effect size increased with an increase in the duration, number, length of exercise session. Conclusion : Aquatic exercise therapy appears to show a moderate effect on balance in patients with chronic stroke. A meta-analysis is warranted for further research to determine the effects of aquatic exercise on walking, muscle strength, and range of motion.

• 한국군사과학기술학회지
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• 제15권4호
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• pp.435-441
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• 2012

This paper provides simulation-based results of effect analysis of sample size and sampling periods on accuracy of reliability estimation methods using multiple comparisons with analysis of variance. Sum of squared errors in estimated reliability measures were evaluated through applying seven estimation methods for one-shot systems to simulated quantal-response data. Analysis of variance was implemented to investigate change in these errors according to variations of sample size and sampling periods for each estimation method, and then the effect analysis on accuracy in reliability estimation was performed using multiple comparisons based on sample size and sampling periods. An efficient way to allocate both sample size and sampling periods for reliability estimation tests of one-shot systems is proposed in this paper from the effect analysis results.