• Journal of the Korean Institute of Telematics and Electronics S
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• v.34S no.2
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• pp.1-10
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• 1997

In this paper, an improved lower bound on the burst-error correcting capability of th ecyclic product code is presented and through the analysis of this new bound clustered cyclic product (CCP abbr.)code is proposed. The CCP code, to improve the burst-error correcting capability, combines the idea of clustering and the transmission method of cyclic product code. That is, a cluster which is defined in this paper as a group of consecutive code symbols is employed as a new transmission unit to the code array transmission of cyclic product code. the burst-error correcting capability of the CCP code is improved without a loss in the random-error correcting capability and performance comparison in the digital video camera records (DVCR) system shows the superiority of the proposed CCP code over conventional product codes.

• 한국석유지질학회:학술대회논문집
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• spring
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• pp.10-14
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• 1998

A systematic methodology is developed for the electrofacies determination from wireline log data using multivariate statistical analysis. To consider corresponding contribution of each log and reduce the computational dimension, multivariate logs are transformed into a single variable through principal components analysis. Resultant principal components logs are segmented using the statistical zonation method to enhance the efficiency and quality of the interpreted results. Hierarchical cluster analysis is then used to group the segments into electrofacies. Optimal number of groups is determined on the basis of the ratio of within-group variance to total variance and core data. This technique is applied to the wells in the Korea Continental Shelf. The results of field application demonstrate that the prediction of lithology based on the electrofacies classification matches well to the core and the cutting data with high reliability This methodology for electrofacies classification can be used to define the reservoir characteristics which are helpful to the reservoir management.

• Journal of the Korean Home Economics Association
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• v.40 no.2
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• pp.1-13
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• 2002

The purpose of this study is to analyze typologic methods in the Family Studies. For this goal, we reviewed literatures related to social research methodology, and analyzed articles in the Family Studies part on the basis of themes and typologic methods. The major resets can be summarized as follow: Typology methods used to clarify complex and subtle family phenomena and distinguish redundant interaction in everyday life. Especially, they can show family system type, communication mode style, leisure activity type, life altitude type, and personality traits type. Typology was made by the methods as follow: the insight, crossing the two single question, intersecting scale's mean or middle point, cluster analysis, and factor analysis. Typology is useful method in the Family Studies, but the accuracy standard needs in the future studies.

• Journal of The Korean Association For Science Education
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• v.15 no.2
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• pp.194-200
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• 1995

The purpose of this study is to investigate the attitudes related to the science of elementary and middle school students. The instrument used for measuring attitudes was developed by Korea National University of Education. 1488 students were sampled by stratified cluster sampling method. The major findings of this study are as follows. 1.Elementary school students have significantly higher attitude scores than middle school students. 2.The value of Pearson's correlation coefficient among the sub-categories of science attitudes was 0.3773 - 0.6336, which was significant at the 0.001 level. 3.There was no statistically significant difference between grade and sex in middle school students. 4.There was statistically significant difference between grade and sex in elementary school students.

• Publications of The Korean Astronomical Society
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• v.32 no.1
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• pp.49-53
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• 2017

The point sources in the Bright Source Catalogue of the AKARI Far-Infrared Surveyor (FIS) were classified based on their FIR and mid-IR fluxes and colours into young stellar object (YSO) and extragalactic source types using a Quadratic Discriminant Analysis method (QDA) and Support Vector Machines (SVM). The reliability of the selection of YSO candidates is high, and the number of known YSO candidates were increased significantly, that we demonstrate in the case of the nearby open cluster IC348. Our results show that we can separate galactic and extragalactic AKARI point sources in the multidimensioal space of FIR fluxes and colours with high reliability, however, differentiating among the extragalactic sub-types needs further information.

• 한국데이터정보과학회:학술대회논문집
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• 2005.04a
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• pp.185-192
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• 2005

There are many data mining techniques such as association rule, decision tree, neural network analysis, clustering, genetic algorithm, bayesian network, memory-based reasoning, etc. We analyze 2003 Gyeongnam social indicator survey data using k-means clustering technique for environmental information. Clustering is the process of grouping the data into clusters so that objects within a cluster have high similarity in comparison to one another. In this paper, we used k-means clustering of several clustering techniques. The k-means clustering is classified as a partitional clustering method. We can apply k-means clustering outputs to environmental preservation and environmental improvement.

• Journal of the Korean Society of Costume
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• v.54 no.3
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• pp.73-85
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• 2004

The purpose of this study was to investigate the characteristic and sensibility of Japanism fashion designs which represented by Japanese designers and Western designers. The stimulus were 29 pictures of contemporary fashion designs which represented the Japanism style fashion designs from fashion collections. The data were analyzed by Cluster analysis, Factor analysis, Multidimensional Scaling Method and Regression Analysis. The specific objectives were as follows ; 1) As result of design analysis, Japanism fashion sensibility is unique and good-looking. 2) As result of the factor analysis. 4 factors which are Attractiveness, Attention, Maturity and Hardness and softness. 3) According to sensibility positioning, The Japanism fashion design was classified by Decorative-Simple, Hard-Soft. 4) As result of the Regression Analysis, The preference of Japanism fashion design was related to attractive factor. 5) As result of the Regression Analysis. The buying desirable of Japanism fashion design was related to attractive, attentive and mature factor.

• Journal of Mechanical Science and Technology
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• v.20 no.12
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• pp.2168-2177
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• 2006

The purpose of this investigation was to determine the specific fracture mechanics response of cracks that initiate at the stem-cement interface and propagate into the cement mantle. Two-dimensional finite element models of idealized stem-cement-bone cross-sections from the proximal femur were developed for this study. Two general stem types were considered; Rectangular shape and Charnley type stem designs. The FE results showed that the highest principal stress in the cement mantle for each case occurred in the upper left and lower right regions adjacent to the stem-cement interface. There was also a general decrease in maximum tensile stress with increasing cement mantle thickness for both Rectangular and Charnley-type stem designs. The cement thickness is found to be one of the important fatigue failure parameters which affect the longevity of cemented femoral components, in which the thinner cement was significantly associated with early mechanical failure for shot-time period.

• Journal of the Korean Society of Clothing and Textiles
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• v.25 no.3
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• pp.516-524
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• 2001

This dissertation has been intented to grasp the components of personal colors and classify personal colors. The Method of the study was quasi-experimental. In the experiment to evaluate personal colors, the subjects was 315 male and female college students in Taegu and Kyungbuk area. The evaluations were analyzed by SAS and the methods used were descriptive statistics, cluster analysis, T-test. The results obtained were as follows: First, the major components of subjects personal colors were found to be the colors of skin and hair. Secondly personal colors were classified into three types: warm, cool, and ambiguous. Third types of personal colors tended to be different between men and women.

• Journal of the Korean Society for Precision Engineering
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• v.31 no.8
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• pp.677-682
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• 2014

One of the most important element technologies for achieving high-precision in machine tool spindle systems is preload technology for the bearing of spindle systems. Fixed position preload, constant pressure preload, conversion preload and variable preload methods have been applied for the spindle systems. In this study, a new variable preload method using centrifugal force and rubber pressure is used for reducing installation costs through simplifying its structure. The main objective of the work is the verification of the operability in a preload device using the rubber pressure by the finite element analysis. It is shown that the variable preload device proposed in this study is applicable to high speed machine tool spindles.