• Korean Journal of Child Studies
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• v.28 no.4
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• pp.35-49
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• 2007

Data from the Seoul Panel Study of Children were analyzed for structural relationshipsamong types of child abuse, depressive tendencies, self-efficacy, and academic achievement. Subjects consisted of 1,785 fourth-grade elementary school children in 2004. Structural equation modeling was employed for statistical analyses. The results were that emotional abuse was indirectly related to academic achievement via depressive tendencies and self-efficacy; children who experienced emotional abuse were more likely to have higher depressive tendencies and lower self-efficacy, which in turn, resulted in lower academic achievement. Neglect was directly related to low academic achievement. In contrast, physical abuse had no relationship with these factors. Implications for practice from this study were discussed.

• The Korean Journal of Ecology
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• v.23 no.2
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• pp.175-180
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• 2000

In order to study the insect-insect interaction of the insect community associated with Rumex obtusifolius. this experiment was designed in such a way that the feeding of one insect could indirectly affect the subsequent insect species through the changes in host plant (plant mediated insect-insect interaction ). Philaenus spumarius and Gastrophysa viridula were selected for the experiment. To investigate the effect of P. spumarius feeding on the ecology of G. viridula, first, statistical analyses were carried out. As results. no significant difference between Control and Experimental was found in the development patterns (Repeated Measures ANOVA, F=0.744, p=0.667) and survivorships (F=0.373. p=0.990). As the results from this experiment show, there was no effect on the ecology of G. viridula due to the previous feeding by P. spumarius on R. obtusifolius leaves.

• Speech Sciences
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• v.7 no.1
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• pp.217-232
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• 2000

In this study, I investigate the role of post-consonantal fundamental frequency (F0) as a cue for automatic distinction of types of Korean stops and affricates. Rather than examining data obtained by restricting contexts to a minimum to prevent the interference of irrelevant factors, a relatively natural speaker independent speech corpus is analysed. Automatic and statistical approaches are adopted to annotate data, to minimise speaker variability, and to evaluate the results. In spite of possible loss of information during those automatic analyses, statistics obtained suggest that vowel F0 is a useful cue for distinguishing manners of articulation of Korean non-continuant obstruents having the same place of articulation, especially of lax and aspirated stops and affricates. On the basis of the statistics, automatic classification is attempted over the relevant consonants in a specific context where the micro-prosodic effects appear to be maximised. The results confirm the usefulness of this effect in application for Korean phone recognition.

• Journal of the Korean Institute of Telematics and Electronics A
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• v.31A no.5
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• pp.50-57
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• 1994

The analysis of the two-tone intermodulation distortion of multistage two-ports with gain and mismatching losses is presented with simplified two-port analyses and statistical viewpoint. The uncertainty obtained from unknown phase angles of the intermodulation distortion signals to the system designer is reduced using stochastic process, hence improving the accuracy of the solution. Based on the dc power dependance of third-order intercept point of each stage, the new efficient method for improving the total intercept point is also suggested with only the relation of dc power and available power gain criteria. Experimental verification on specific amplifiers used for cellular mobile communication comparing predicted and measured intercept points for various power conditions is presented.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 2003.05a
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• pp.741-743
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• 2003

A surface mount machine operation policy to assemble printed circuit boards is being developed in this research. The policy includes how to assign electronic components to slots on a component rack, and how to determine placement sequences on printed circuit board. The suggested heuristic uses information about component types and closeness relationships in each component on the board to assemble. First, the size of components and closeness ratings are used to divide them into two different size groups. Then rack assignment and placement routes are developed using component type and quantity information for a small size group, and followed by a large size group. Simulation models are developed using Visual C++ for performance evaluation of the heuristic. Necessary statistical analyses are provided to show the effectiveness of the suggested heuristic.

• Journal of the Korean Society of Costume
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• v.49
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• pp.65-72
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• 1999

The purpose of this study was to investigate the relationships between body-calthexis and clothing image preferences in male college students. The sample included 28 male college students and an instrument was developed based on the previous studies. The statistical analyses used for this study were factor analysis cluster analysis and t-test. The result of factor analysis showed that body-cathexis consisted of four areas of body parts: face/head upper body middle body and lower/total body. Clothing image preferences consisted of 'strong vs weak' 'soft vs hard' 'young vs mature' 'mannis vs feminine' and 'distinguished vs undistinguished' images. Cluster analysis revealed that male college students are segmented into two groups. and the two groups differed in regard to clothing image preferences such as 'strong vs weak' 'young vs mature' and 'mannish vs feminine' images. In addition the two consumer segments were different concerning body-cathexis for middle body and all body areas combined. The consumers who preferred feminine weak and mature clothing images were more satisfied with their middle area of the bodies and all body areas combined.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.22 no.9
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• pp.889-895
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• 2012

A vertical launching system(VLS) is a system for holding and firing missiles on surface ships. When a missile is launched in VLS, relative motion between canister and missile and drag force induced by wind can cause initial unstability of a missile. Thus dynamic analysis of initial behavior of vertically launched missile should be performed to prevent collision with any structure of a ship. In this study, dynamic analyses of initial behavior of vertically launched missile are performed using Monte-Carlo simulation, which relys on random sampling and probabilistic distribution of variables. Each parameter related with dynamic behavior of a missile is modeled with probability variables and Recurdyn, a commercial software for multi body dynamic analysis, is used to perform Monte-Carlo simulation. As a result, initial behavior of a missile is evaluated with respect to various performance indexes in a probabilistic sense and sensitivity of the each parameters is calculated.

• Proceedings of the KSPS conference
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• 2007.05a
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• pp.227-229
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• 2007

We investigate whether the word frequency effects occur in native speakers' homophone speech in such a way that less frequent words are produced with greater magnitudes in duration and F0 than more frequent words. Acoustic analyses of homophone data produced by four speakers reveal that there is a tendency that vowels in less frequent words get longer than those in more frequent words, and statistical tests verify the significance of their differences. On the other hand, no considerable correlation has been discovered between F0 and word frequency.

• English Language & Literature Teaching
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• v.18 no.2
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• pp.149-170
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• 2012

The purpose of the present study is to examine the degree to which the writing instruction using animations has effects on the writing performance of $4^{th}$ year elementary school students. This study also examined the effects of the animation-based writing instruction on the interest and confidence of those students. To this aim, the present study utilized a set of writing tests and questionnaires before and after the instruction. The data were collected from 63 elementary school students. The data were then analyzed using a series of statistical analyses. The results suggested that the students who received the writing instruction using animations performed significantly better on the writing test than those who received the textbook-based instruction. The results also suggested that those who received the animation-based instruction showed more positive interest and confidence on English and English learning. Finally, limitations of the present study and suggestions for further studies are discussed at the end of the paper.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.23 no.58
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• pp.101-111
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• 2000

This study uses financial statements on several hundred companies listed in the Korea Stock Market to analyze trends in inventory turnover ratios and examine the effect of inventory performance on the profitability of the companies. Statistical analyses are done to determine if there have been significant changes in inventory turnover ratios and how turnover ratio pattern varied by factors such as industry, size of the firm, and the effectiveness of previous inventory management. Inventory turnover ratios decreased for four consecutive years and were found to vary by industry. Also it is proved that there was statistically significant relationship between the size of the firm and the average level of inventory as a fraction of sales. Regression analysis is done to investigate the relationship between the inventory management performance and profitability of companies and it is found that improvement in inventory level affected profitability of the companies.