• Proceedings of the Korean Society For Composite Materials Conference
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• 2003.04a
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• pp.169-172
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• 2003

Manufacturing process for autonomic microcapsules was introduced and autonomic microcapsules were manufactured by varying with various manufacturing process variables. Urea-formaldehyde resin was used for the wall of microcapsules and DCPD (dicyclopentadiene) was used for the self-healing agent. The characteristics of these microcapsules was evaluated through a particle size analyaer, an optical microscope, and a TGA. The various manufacturing process variables, such as pH and agitation speed of the emulsified solution, were considered to focus in this study. According to the results, the particle size distributions were affected on the agitation speed of the emulsified solution, and the thermal stability was influenced by pH of the emulsified solution.

• Journal of Korean Society for Quality Management
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• v.33 no.1
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• pp.88-98
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• 2005

This paper considers a six sigma project for improving the TIP life time in a spot welding process. The project follows a disciplined process of five phases: define, measure, analyze, improve, and control. A process map is used to identify process input and output variables. Nine key process input variables are selected by using C&E matrix and FMEA, and finally four vital few input variables are selected from analyze phase. The optimum process conditions of the vital few input variables are jointly obtained by maximizing TIP life time using DOE and alternative selection method.

• Journal of the Korean Society of Clothing and Textiles
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• v.22 no.3
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• pp.341-352
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• 1998

The purpose of this study was to investigate the effect of clothing cues (color, color scheme, structure) on impression formation by perceiver personality variable. The subjects were consisted of 77 male and 86 female undergraduate and graduate students. The experimental inventories for this study were a set of stimuli, a response scale, standardized MBTI. The stimuli were eighteen photographs and one extra photograph of a female wearing Korean dress, Chima and Jokori-varied in hue (cool, warm), color scheme (related schemes, con- trasting schemes) of the same silhouette. Results indicate that the most affecting perceiver's personality variables on impression effects were judging-perceiving traits and extraversion -introversion traits. The interaction effects were most frequently appeared between color scheme (clothing cues) and perceiver's personality traits. The impression factors which were most affected by perceiver's personality traits variables were preference· evaluation factor and individuality· attention factor.

• Journal of the Korean Home Economics Association
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• v.39 no.8
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• pp.121-136
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• 2001

The purpose of this study was to analyze the effects of financial attitudes and financial communication on financial satisfaction. For this study, in 2000, questionnaires developed by the researcher were given to 320 households in Kwangju. resulting in 262 households with usuable data. The data were analyzed by various statistical methods such as frequency, percentile, correlation analysis, t-test, Anova, Multiple Regression analysis. The major findings of this study were as follows; 1) Financial attitudes were significantly different according to age and monthly savings 2) Financial communication was significantly different according to age and financial subjective variables. 3) Financial satisfaction was significantly different according to monthly income, monthly savings, monthly living costs, debt, financial subjective variables and financial communication. The set of socio- economic characteristics variables accounted for 3% of the variance in the financial satisfaction. But the addition of subjective characteristics variables, financial attitude, financial communication resulted in an $R^2$ change of 20, 23, 26%.

• Korean Journal of Human Ecology
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• v.2 no.1
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• pp.25-37
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• 1999

The purposes of this research were to find out general trends of employed women's stress and to investigate the differences and effects of related variables. The data were obtained through 239 employed women living in Kwangju and Chonnam. The major findings were as follows : 1) Employed women's scores of stressor, stress cognition and distress were under medium but coping scores were relatively high. 2) Significant differences in employed women's stressors were found according to age, income, job satisfaction, and family life cycle. Stress cognition differed according to job adjustment conditions and self-esteem. Also distress related with job conditions and object. Stress coping levels were different according to income, job conditions, self-esteem, and sex-role attitude. 3) In analyzing the causal effects among related variables, employed women's stressors were affected by job satisfaction and age. Also stress cognition were influenced by job satisfation and self-esteem. Job conditions showed significant effects on distress and self-esteem, sex-role attitudes showed on coping. Conclusively job satisfaction, self-esteem and gender equality were most important variables for employed women's stress. (Korean J of Human Ecology 2(1) : 25-37 1999)

• Korean Journal of Child Studies
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• v.26 no.4
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• pp.157-171
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• 2005

Causal relationships between school maladjustment and related variables were examined in 371 5th grade elementary school students. School maladjustment was ascertained by revised the School Adjustment Test(Lim, 1993; Song, 1999). After analysis of differences in internal locus of control, academic stress, and academic achievement between the school maladjusted and adjusted groups, the study built a structural equation model of school maladjustment-related variables goodness of fit was tested with LISREL 8 for Windows. Significant differences were found in internal locus of control, academic stress, and academic achievement by level of school maladjustment. Internal locus of control, academic stress, and academic achievement both directly and/or indirectly influenced school maladjustment. These variables explained 64% of the variances in school maladjustment.

• Journal of Mechanical Science and Technology
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• v.20 no.10
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• pp.1730-1740
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• 2006

A nodeless variables finite element method for analysis of two-dimensional, steady-state viscous incompressible flow is presented. The finite element equations are derived from the governing Navier-Stokes differential equations and a corresponding computer program is developed. The proposed method is evaluated by solving the examples of the lubricant flow in journal bearing and the flow in the lid-driven cavity. An adaptive meshing technique is incorporated to improve the solution accuracy and, at the same time, to reduce the analysis computational time. The efficiency of the combined adaptive meshing technique and the nodeless variables finite element method is illustrated by using the example of the flow past two fences in a channel.

• International Journal of Highway Engineering
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• v.15 no.5
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• pp.31-45
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• 2013

PURPOSES : Determination of particle packing model variables that can be used for formulation of new DEM based particle packing model by examining existing particle packing models METHODS : Existing particle packing models are thoroughly examined by analytical reformulation and sensitivity analysis in order to set up DEM based new particle packing model and to determine its variables. All model equations considered in this examination are represented with consistent expressions and are compared to each others to find mathematical and conceptual similarity in expressions. RESULTS : From the examination of existing models, it is observed that the models are very similar in their shapes although the derivation of the models may be different. As well, it is observed that variables used in some existing models are comprehensive enough to estimate particle packing but not applicable to DEM simulation. CONCLUSIONS : A set of variables that can be used in DEM based particle packing model is determined.

• Communications for Statistical Applications and Methods
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• v.12 no.2
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• pp.531-538
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• 2005

In k-means clustering, we standardize variables before clustering and iterate two steps: units allocation by Euclidean sense and centroids updating. In applications to DB marketing where clusters are to be used as customer segments with similar consumption behaviors, we frequently acquire additional variables on the customers or the units through marketing campaigns a posteriori. Hence we need to modify the clusters originally formed after each campaign. The aim of this study is to propose a revision method of k-means clusters, incorporating added information by weighting clustering variables. We illustrate the proposed method in an empirical case.

• Computers and Concrete
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• v.24 no.5
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• pp.399-412
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• 2019

In this investigation, Elman neural networks were utilized for predicting the mechanical properties of Self-Compacting Concretes (SCCs). Elman models were designed by using experimental data of many different concrete mixdesigns of various types of SCC that were collected from the literature. In order to investigate the effectiveness of the selected input variables on the network performance in predicting intended properties, utilized data in artificial neural networks were considered in two sets of 8 and 140 input variables. The obtained outcomes showed that not only can the developed Elman ANNs predict the mechanical properties of SCCs with high accuracy, but also for all of the desired outputs, networks with 140 inputs, compared to ones with 8, have a remarkable percent improvement in the obtained prediction results. The prediction accuracy can significantly be improved by using a more complete and accurate set of key factors affecting the desired outputs, as input variables, in the networks, which is leading to more similarity of the predicted results gained from networks to experimental results.