• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2005.10a
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• pp.291-294
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• 2005

Recently, the usage of aluminum alloy is rapidly increasing in automobile industry to achieve weight reduction for fuel efficiency. However, design of forming process of aluminum is more difficult than steel because of poor formability and severe springback. Since applications of finite element analysis for the design of sheet metal forming process are actively performed, it is required to conduct proper consideration of aluminum material behavior. In this study, a plane stress yield function Yld2000(Yoon et al., 2000), proven to describe well the anisotropic behavior of aluminum alloy, is implemented for FE analysis. One element test is considered to verify the validity of implementation of Yld2000 model. In addition, cylindrical cup drawing test is performed to verify earing shape of a drawn cup.

• Journal of the Korean Society of Clothing and Textiles
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• v.23 no.8
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• pp.1119-1130
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• 1999

The purpose of this was to investigate the differences in recognition of brand and advertisement image according to the life style segments of adolescents. The subjects selected for the final analysis were 613 female high school students whoe were residents in Seoul Pusan and Taejeon. The statistics used for data analysis were factor analysis one-way ANOVA Duncan's multiple range test paired t-test frequency distribution and percentage by the SPSS program The results of this study were as follows : 1. The life style of adolescents wee classified into five groups : Sports Uninterest group Friend Preference/Fashion Uninterest group Sports Preference/Home Oriented group Fashion Interest group and Confidence group. 2, The brand image and advertisement image recognition didn's correspond in general 3. The brand image and advertisement image recognition were significantly different among five groups of life style. The Confidence group and Friend Preference/ Fashion Uninterest group recognized brand image and advertisement image lower than the other groups.

• Korean Journal of Child Studies
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• v.30 no.5
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• pp.1-8
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• 2009

For the purpose of this analysis of trends in research on creativity of preschool children, 98 volumes with articles on the creativity of preschool children were selected from 6 reliable Korean academic journals. Analysis was for year, content, research methods, research design, and subjects. Results showed that (1) the changes by year were that the number of qualitative researches increased from 4 articles in 1998 to 24 articles in 2006. (2) The greatest amount of research content concerned educational methods for the generation of creativity. (3) Most research methods were empirical studies. (4) The most used measurement scale was the Korean Comprehensive Creativity Test for Young Children (Jeon, 2000). (5) Most data analyses were by t-test.

• The Research Journal of the Costume Culture
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• v.14 no.3 s.62
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• pp.366-380
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• 2006

The purpose of this study was to examine the effect of shopping orientations on clothing purchasing behavior according to residence. The data was obtained from questionnaires filled out by 530 females living in Seoul and Jecheon. For data analysis, factor analysis, ANOVA, t-test, Cronbach's $\alpha$, Duncan's multiple range test and cluster analysis were used. For shopping orientation, five factors of orientation were found and labeled as hedonism, brand and store loyalty, conformity, economy and rationality factor. Based on five shopping orientation factors, women were classified into five clusters(self-centered and rational, recreational, economy and shopping low involvement, economical and conformative cluster). Each cluster showed significantly different clothing purchasing behaviors (problem recognition, information search and evaluative criteria) and had different demographic variables(age, income, marital status and school career). Finally, residence and shopping orientations have influenced various clothing purchasing behavior. In conclusion, residence was the important factor which influenced on shopping orientation and clothing purchasing behavior.

• Journal of the Korean Home Economics Association
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• v.26 no.3
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• pp.153-169
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• 1988

This study aimed at investigating the socialization of householdwork to the difference of life style pattern of housewives. For the purpose, questionnaires were administrated to the housewives in Seoul and to analyse of the date, factor analysis F-test, t-test and path analysis were used. The results can be summarized as follows ; 1. By utilizing factor analysis, the life style patterns of housewives were classified into 7 types, they were named, self-improvement type, social activity type, modernistic type, sound and thrifty type, variety-seeking type, passive stability-seeking type, the traditional and conservative type. And the patterns of life style differed significantly according to all of the demographic variables except family type. 2. The level of socialization of householdwork was not reaching the medium, and the mean was 19.45. 3. The socialization of householdwork were influenced indirectly by the age, educational level, income level, family type and social activity type, variety seeking type, traditional and conservative type of the life style pattern. And directly, the age and educational level influenced the socialization of householdwork.

• Journal of the Korea Society of Computer and Information
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• v.22 no.11
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• pp.143-149
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• 2017

In this paper, we propose efficient management method of liberal education for improving computer literacy. We analyzed the actual conditions and factors affecting education and reflected the analysis results in education. The subject of the study is 'Practice Excel', and tested achievement based on computer literacy. In order to evaluate objectively, we conducted CBT(Computer Based Test) based on Computer Specialist in Spreadsheet & Database Level-2. Analysis of the questionnaire included the use of the popular statistical program, IBM SPSS 24 trial, and frequency, ANOVA, t-test, crossover analysis, and correlation. Evaluation results, An important factor influencing educational performance was active participation. It also proved to be very helpful for understanding excel functions & expression.

• Journal of Korean society of Dental Hygiene
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• v.21 no.3
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• pp.227-234
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• 2021

Objectives: The objective of this study was to investigate the relationship between smoking history and periodontal disease among the elderly in South Korea. Methods: The study subjects comprised 2,703 elderly people who underwent oral health examination as part of the 7th South Korea National Health and Nutrition Examination Survey (KNHANES; 2016-2018). Data were analyzed using frequency analysis, Rao-Scott chi-square test, t-test, and binary logistic regression analysis. Results: A complex sample logistic regression analysis showed that the odds for periodontal disease development were higher in past smokers (odds ratio [OR]=1.461; 95% CI=1.070-1.994) and current smokers (OR=1.601; 95% CI=1.011-2.536) than in lifetime non-smokers. Conclusions: Smokers must actively participate in smoking cessation programs and interventions starting from middle age.

• 한국전산유체공학회:학술대회논문집
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• 1998.05a
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• pp.168-173
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• 1998

A numerical analysis of axisymetric backward facing step main nozzle flow in air jet loom has been accomplished. To obtain basic design data for an optimum main nozzle for an air-jet loom and to predict the transonic/supersonic flow, a characteristic based upwind flux difference splitting compressible Navier-Stokes method has been used. The wall static pressure of the main nozzle and the flow velocity changes in the nozzle tube were analyzed by changing air tank pressures and acceleration tube lengths. The flow inside the nozzle experiences double choking one at the needle tip and the other at the acceleration tube exit at tank pressures over $4kg_f/cm^2$. The tank pressure $P_t$ leading to the critical condition depends on the acceleration tube length; i.e, $P_t$ is higher for longer acceleration tubes. The $P_t$ value required to bring the acceleration tube exit to the critical condition is nearly constant regardless of acceleration tube length. The round needle tip shape might lead to less total pressure loss when compared with step shape.

• Journal of the Korean Society for Precision Engineering
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• v.25 no.4
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• pp.108-117
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• 2008

A transmission designed with P.T.O(Power Take-Off) axle for agricultural work vehicles including multi-purpose vehicles has been developed. It is focused on the 4-wheel drive transmission of synchronous contact type for practical use in fruit tree households which is required for a large-sized agricultural vehicle. Concerning to the specification performed, the load capacity is from 500kg to 1,000kg and the safety should be secured for passengers. In addition, the driving condition should also be secured under bad situations of the topographic slope, swampy land and the rest. In order to carry out above tests, a prototype vehicle through strength analysis of transmission design has been manufactured. Consequently, optimal design conditions on the power transmission with multi-purpose vehicle for various jobs are proposed such as an indication of optimal RPM and torque at a certain work situation. The performance test through the prototype of multi-purpose work vehicle is performed and the related data base is achieved. Finally, it is improved on troubles by the analysis of the results of R&D and provided the solutions on problems occurring to mass production in the future.

• Korean Journal of Pharmacognosy
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• v.28 no.4
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• pp.286-292
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• 1997

We studied the screening condition for immune regulatory responsor. We focused on the T-lymphocytes leer this purpose. Mouse fetal thymic organ culture (FTOC) system and flow cytometric analysis were mainly used in this experiment. Even if FTOC is carried out in vivo condition, the pattern of thymic development in the condition of FTOC is similar to that of in vivo condition. In this regard, FTOC system might be very powerful tool to screen the immune regulator, especially concerning on T cells. To establish the optimum condition of FTOC to screen the Immune regulator, we focused on the optimum amount of dose and culture period. The cell number and surface antigens on T cells were also analysed by using hemacytometer and flow cytometer. To monitor the differentiation event, anti-CD3, anti-CD4 and anti-CD8 antibodies were used. Alkoxyglycerol and Phellodendri Cortex were used fur positive and negative control, respectively. Astragalus membranceus was used as test sample. From our analysis, we reached to conclusions that the best dose of extract is $50\;{\mu}g/ml$ of culture medium, the best culture period is for 9 days, and ethanol used as solvent has no toxicity to FTOC.