• 한국전산유체공학회:학술대회논문집
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• 2009.11a
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• pp.13-18
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• 2009

Flight vehicles such as wheel wells and bomb bays have many cavities. The flow around a cavity is characterized as an unsteady flow because of the formation and dissipation of vortices brought about by the interaction between the free stream shear layer and the internal flow of the cavity. The resonance phenomena can damage the structures around the cavity and negatively affect the aerodynamic performance and stability of the vehicle. In this study, a numerical analysis was performed for the cavity flows using the unsteady compressible three-dimensional Reynolds-Averaged Navier-Stokes (RANS) equation with Wilcox's turbulence model. The Message Passing Interface (MPI) parallelized code was used for the calculations by PC-cluster. The cavity has aspect ratios (L/D) of 2.5 ~ 7.5 with width ratios (W/D) of 2 ~ 4. The Mach and Reynolds numbers are 0.4 ~ 0.6 and $1.6{\times}106$, respectively. The occurrence of oscillation is observed in the "shear layer and transient mode" with a feedback mechanism. Based on the Sound Pressure Level (SPL) analysis of the pressure variation at the cavity trailing edge, the dominant frequencies are analyzed and compared with the results of Rossiter's formula. The dominant frequencies are very similar to the result of Rossiter's formula and other experimental data in the low aspect ratio cavity (L/D = ~ 4.5). In the large aspect ratio cavity, however, there are other low dominant frequencies due to the leading edge shear layer with the dominant frequencies of the feedback mechanism. The characteristics of the acoustic wave propagation are analyzed using the Correlation of Pressure Distribution (CPD).

• Proceedings of the Korean Society of Plant Pathology Conference
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• 2003.10a
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• pp.130-130
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• 2003

Gummy stem blight pathogen is very difficult not only to monitor the inoculum levels prior to host infection, and also it is destructive and hard to control in field condition. We have applied RAPD technique to elucidate the genetic diversity of the genomic DNA of Didymella bryoniae and also to generate specific diagnostic DNA probe useful for identification and detection. The 40 primers produced clear bands consistently from the genomic DNA of twenty isolates of Didymella bryoniae, and two hundred seventy-three amplified fragments were produced with 40 primers. The combined data from 273 bands was analyzed by a cluster analysis using UPGMA method with an arithmetic average program of NTSYS-PC (Version 1.80) to generate a dendrogram. At the distance level of 0.7, two major RAPD groups were differentiated among 20 strains. RAPD group (RG) I included 8 isolates from watermelon except one isolate from melon. RAPD group (RG) IV included 12 isolates from squash, cucumber, watermelon and melon.. In amplification experiment with SCAR specific primer RG1F-RG1R resulted in a single band of 650bp fragment only for 8 isolates out of 20 isolates that should be designated as RAPD Group 1. However, same set of experiment done with RGIIF-RGIIR did not result in any amplified product.. Our attempts to detect intraspecific diversity of ITS region of rDNA by amplifying ITS region and 17s rDNA region for 20 isolates and restriction digestion of amplified fragment with 12 enzymes did not reveal polymorphic band. In order to develop RAPD markers for RGIV specific primer, a candidate PCR fragment( ≒1.4kb) was purified and Southern hybridized to the amplified fragment RGIV isolates. This promising candidate probe recognized only RGIV isolates

• Journal of the Korea Fashion and Costume Design Association
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• v.19 no.2
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• pp.101-115
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• 2017

This study classified social stratum variables of adults in their 20s to 50s by subjective and objective measurements and classified leisure activities into groups to examine the conspicuous consumption of leisure apparel. A total of 365 adults in their 20s to 50s living in Daegu and the Kyungbuk area were selected considering their jobs and residences. SPSS PC+ 20.0 was used to analyze the data with frequency analysis, factor analysis, reliability examination, cluster analysis, ANOVA, Duncan-test, Scheffe-test, and ${\chi}^2-test$. The results of this study are shown as follows. First, 'Jogging/Walking' was found to be the most favorable activity in the examination of leisure sports activities among the participants and showed a difference in gender. Second, leisure activities were pastime-culture activity, sports activities, static activity, volunteering, and relaxing, and these activities were grouped into non-participant, active and passive leisure activities. Conspicuous consumption of leisure apparel was classified into personality oriented, luxury goods-oriented, and other people-oriented. Third, there was a significant difference in the sub-factors of the conspicuous consumption of leisure apparel (personality oriented, luxury goods-oriented, other people-oriented) according to the sub-factors of subjective stratum(economic power, social position, level of consumption, cultural level and overall stratum consciousness). Fourth, there was significance in the objective social stratum variable by the types of leisure activities. Significant differences were found in personality orientation, luxury goods-oriented, and other people-oriented in conspicuous consumption of leisure apparel by the types of leisure activities. Finally, there were significant differences in economic power, level of consumption, cultural level of subjective social stratum by gender, sports activities and volunteering in leisure activities, as well as other people-oriented conspicuous consumption of leisure apparel. This study also found significant differences in economic power, level of consumption and cultural level of social stratum by age, as well as other people-oriented conspicuous consumption of leisure apparel.

• Horticultural Science & Technology
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• v.17 no.3
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• pp.352-354
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• 1999

Randomly and specifically amplified polymorphic DNA band patterns based on polymerase chain reaction (PCR) analysis were used to assess genetic variation of somaclonal variants obtained from tissue culture of lisianthus (Eustoma grandiflorum). Five different types of variant were classified by morphological characters such as leaflet number, leaf shape, caulicle length, plant height, and leaf area. Five primers out of 20 primers (10 mer) resulted in 34 random amplified DNA fragments with polymorphisms (64.7%) in all tested plants. The dissimilarity coefficient was from 0.71 to 0.91 by UPGMA cluster analysis. Based on the presence of polymorphic bands, normal plant and five somaclonal variants were divided into two groups at the similarity coefficient value of 0.79.

• Journal of the Korean Society of Costume
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• v.55 no.3 s.93
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• pp.81-93
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• 2005

The purpose of this study was to identify Chinese new generation women's clothing exploratory behavior according to their sensitivity pursuit propensity. The respondents were 500 Chinese new generation women residing in Soju City, China. Frequencies, percent, mean, one-way ANOVA, factor analysis, Chi-square test, and cluster analysis were done by use of SPSS PC+. The results were as follows; 1. The factors of sensitivity pursuit propensity were adventure & diversity, change, new atmosphere, and artistic sensitivity. And factors of clothing exploratory behavior were brand turnover, innovative clothing purchasing or wearing, clothing information collection through visiting store, and clothing information collection through contacting neighbors or advertisement. 2. The Chinese new generation women were classified into the creativity pursuit, the adventure & change pursuit, the multi-sensation pursuit, and the sensation retard according to their sensitivity pursuit propensity. 3. The creativity pursuit explored clothing for brand turnover and information through visiting store, communication, or advertisement, were found more among the unmarried late 20's with higher education and jobs. The adventure & change pursuit explored clothing information through visiting store, were found more among the unmarried university students in early 20's. The multi-sensation pursuit explored innovative clothing purchasing, were found more among the unmarried early 20's with jobs or students. The sensation retard explored clothing information through communication or advertisement, considered quality more, were found more among the married early 30's with lower education level and jobs.

• Journal of the Institute of Electronics and Information Engineers
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• v.50 no.8
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• pp.203-211
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• 2013

Due to the rapid growth of mobile devices and applications, mobile cloud computing is becoming an important platform in the development of cloud services. However, the mobile cloud computing is facing many challenges in terms of the computing resources and communications. One of them is the performance issue between mobile devices and cloud server. In the paper, we implemented a hadoop-based android mobile application, called mobile TPC-C, and used it for evaluating the performance aspect between mobile devices and cloud server. The mobile TPC-C was implemented based on the existing TPC-C, to make it possible to execute on top of android mobile devices. The performance measurement using mobile TPC-C was executed on various transactions while changing the number of mobile clients. By comparing it to the evaluation on the personal PC, we tried to point out the important aspects affecting the performance improvement between mobile clients and cloud server.

• Journal of KIISE:Computer Systems and Theory
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• v.36 no.5
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• pp.351-359
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• 2009

Recently with increase of data in the Internet, platform technologies that can process huge data effectively such as Google platform and Hadoop are regarded as worthy of notice. In this kind of platform, there exist network I/O overheads to send task outputs due to the MapReduce operation which is a programming model to support parallel computation in the large cluster system. In this paper, we suggest applying of TIPC (Transparent Inter-Process Communication) protocol for reducing network I/O overheads and increasing network performance in the distributed computing environments. TIPC has a lightweight protocol stack and it spends relatively less CPU time than TCP because of its simple connection establishment and logical addressing. In this paper, we analyze main features of the Hadoop-based distributed computing system, and we build an experimental model which can be used for experiments to compare the performance of various protocols. In the experimental result, TIPC has a higher bandwidth and lower CPU overheads than other protocols.

• The Journal of the Korea Contents Association
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• v.9 no.3
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• pp.329-335
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• 2009

The purpose of this study was to analyze effect of participation satisfaction, absorption on exercise adherence of Elementary Student Hapkido participants. Data was collected from a questionnaire designed for this study consisted of fixed alternative choice response to item constructed to represent the operational definition for each variable. The inventory was administered to stratified cluster random sampling 315 Elementary Student Hapkido participant in Daejeon City Hapkido Alliance. Statistics employed the study to data analysis were frequency, correlation, regression analysis. Based on the result of the study, the following conclusion appears warranted: First, participation satisfaction of Hapkido influence exercise adherence of Elementary Student Hapkido participants. Secondly, participation absorption of Hapkido influence exercise adherence of Elementary Student Hapkido participant.

• The Journal of Korean Society for School & Community Health Education
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• v.12 no.1
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• pp.45-58
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• 2011

Objectives: The purpose of this study is to analyze the fators affecting Internet addiction among adolescents in an area. Methods: By using cluster sampling, 2,479 participants representing 22 elementary school, 11 middle school, 7 high school students in a county of the Chungcheongnam-do. Data was analyzed by SPSS 12.0. using t-test, F-test, chi-square test, Pearson correlation coefficient and multiple regression. Results: Internet addiction positively correlated with high school students(dummy variable), Internet-connected computers in PC Game Room(dummy variable), Internet using time(weekday) and Internet using time(weekend). Internet addiction negatively correlated with Internet-connected computers in school(dummy variable), Internet-connected computers in friend's house(dummy variable). For the male students, Significant factors affecting Internet addiction were eating habits, Internet-connected computers in friend's house, Internet using time(weekend). For the female students, Internet using time(weekday) and Internet using time(weekend) were significant. For the elementary school students, Significant factors affecting Internet addiction were Internet using tine(weekday) and Internet using time(weekend). In the case of the middle school students, Internet using tine(weekday), Internet using time(weekend) and eating habits were significant. but, the high school students, Internet using time(weekend) was significant. Conclusions: Students who spend more time in the internet have higher tendency to become addicted to the internet. Therefore, it would be necessary to develop program to prevent internet addiction.

• Journal of the Korean Society of Clothing and Textiles
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• v.22 no.3
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• pp.396-406
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• 1998

The purpose of this study was to classify the types of salespeople in the apparel stores. A questionnaire was administered to 267 fashion sales related persons in apparel store in downtown, Daegu. Data were analyzed by using frequency, i-test, cluster analysis, MANOVA, ANOVA and Duncan test by using J.M.p(v.2.01) Mac. program and SAS for windows(v. 6.02) PC program. The results of this study were as follows: The types of salespeople were classified into 4 types: "complaining type as a salespeople", "sensitive type for other affairs than their duty", "satisfying as a salespeople" and "performance reaction type". There were significant differences in academic background, selling apparel type/apparel store type, and in all factors in job satisfaction/dissatisfaction, attitude toward working condition, customer type, and selling training by the different types of salespeople. Complaining type as a salespeople were dissatisfied with most items related with job attitude and showed negative response as salespeople. Sensitive type for other affairs than their duty responded more keenly to other affairs than their duty and showed the highest dissatisfaction on the job dissatisfaction factors, and showed the most emotional reaction on attitude toward working condition, customer type, and regulation. Satisfying type as salespeople showed the positive and active attitude for their job. Performance reaction type were satisfied with their job as salespeople only when their performance is tangible as sales increases and showed highest satisfaction only on the job satisfaction factors. The necessity of professional training was shown in all types of salespeople.g was shown in all types of salespeople.