• 한국정보과학회논문지:데이타베이스
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• 제32권3호
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• pp.228-242
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• 2005

투영 클러스터링은 고 차원 데이타집합에서 서로 다른 부분공간들에서 클러스터들을 찾으려고 모색한다. 사용자가 출력 클러스터들의 개수와 투영 클러스터들의 부분공간의 평균 차원수를 지정하지 않아도, 거의 최적인 투영 클러스터들을 탐사해내는 알고리즘을 제안한다. 클러스터링의 각 단계에서 알고리즘의 목적 함수는 투영 에너지, 품질, 그리고 이상치들의 개수를 계산한다. 클러스터링에서 투영 에너지를 최소화하고 품질을 최대화하기 위하여, 전체 차원의 표준 편차들을 비교함으로 입력 점들의 밀도 상에서 각 클러스터의 최선의 부분영역을 찾기 시작한다. 부분공간의 각 차원에 대한 가중치 요소가 투영 거리 측정에서 확률 오차를 없애기 위하여 사용된다. 제안된 알고리즘이 투영 클러스터들을 정확하게 발견해내고 대 용량의 데이타 집합에서 비례확장성을 갖는다는 것을 여러 가지 실험으로 보여준다.

• 한국작물학회지
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• 제44권2호
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• pp.112-116
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• 1999

Genetic diversity of 31 rice varieties including 25 japonica and 6 indica varieties was evaluated using a combination of 19 microsatellite or simple sequence repeats (SSRs) and 28 random decamer oligonucle-otide primers. All 19 microsatellite primer sets representing 19 loci in the rice genome showed polymorphisms among the 31 varieties and revealed 91 alleles with an average of 4.80 bands per primer. Also all 28 random decamer primers used were informative and generated 114 non-redundant bands with a mean of 4.07 bands. Microsatellite markers detected higher number of alleles than random primers .although the mean difference was not statistically significant. A cluster analysis based on Nei＇s genetic distances calculated from the 205 bands resolved the 31 varieties into two major groups that correspond to indica and japonica subspecies, which is consistent with the genealogical information. As few as six random decamer primers or a combination of one microsatellite and four random decamer primers were sufficient to uniquely differentiate all 31 varieties. These combinations would be potentially useful in rice variety protection and identification considering that 25 out of 31 varieties used in this study are japonica rices with high grain quality and have close make up.

• 한국의류산업학회지
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• 제22권1호
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• pp.25-37
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• 2020

This study investigates the clothing purchase behavior of active seniors in their 50s and 60s. Differences of clothing purchase behaviors were examined according to gender and the group classified by shopping orientation. Data were collected from September 2 to September 9, 2019 using a professional internet research panel; subsequently, 246 sets of useful data were analyzed by descriptive statistics, factor analysis, reliability analysis, t-test, chi-squared test, ANOVA and Duncan-test using SPSS 21.0. The results of this study were as follows. First, there were significant differences in clothing purchase behavior of purchase frequency, purchase item, purchase price, and purchase channel according to gender; therefore marketers need plan different merchandising and retailing strategies between man's wear and woman's wear. Second. the result of cluster analysis by shopping orientation showed that active seniors were categorized into four groups including 'active shopping pursuit', 'economic/pleasure pursuit', 'convenience/brand pursuit', and 'passive shopping pursuit'. Third, there were significant differences in demographic variables such as gender and occupation according to four categorized groups. In addition, the significant differences of clothing purchase behaviors were verified according to four groups. 'Active shopping pursuit' group was shown to make the best use of offline channels and online channels in information research and product purchase.

• Journal of Information Science Theory and Practice
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• 제8권2호
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• pp.6-17
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• 2020

Word similarity is often measured to enhance system performance in the information retrieval field and other related areas. This paper reports on an experimental comparison of values for word similarity measures that were computed based on 50 intentionally selected words from a Reuters corpus. There were three targets, including (1) co-occurrence-based similarity measures (for which a co-occurrence frequency is counted as the number of documents or sentences), (2) context-based distributional similarity measures obtained from a latent Dirichlet allocation (LDA), nonnegative matrix factorization (NMF), and Word2Vec algorithm, and (3) similarity measures computed from the tf-idf weights of each word according to a vector space model (VSM). Here, a Pearson correlation coefficient for a pair of VSM-based similarity measures and co-occurrence-based similarity measures according to the number of documents was highest. Group-average agglomerative hierarchical clustering was also applied to similarity matrices computed by individual measures. An evaluation of the cluster sets according to an answer set revealed that VSM- and LDA-based similarity measures performed best.

• 센서학회지
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• 제23권2호
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• pp.99-104
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• 2014

Sensor arrays based on chemical sensors produce multidimensional patterns of data that may be used discriminate between different chemicals. For the human observer, visualization of multidimensional data is difficult, since the eye and brain process visual information in two or three dimensions. To devise a simple means of data inspection from the response of sensor arrays, PCA (Principal Component Analysis) or Sammon's nonlinear mapping technique can be applied. The PCA, which is a well-known statistical method and widely used in data analysis, has disadvantages including data distortion and the axes for plotting the dimensionally reduced data have no physical meaning in terms of how different one cluster is from another. In this paper, we have investigated two techniques and proposed a combination technique of PCA and nonlinear Sammom mapping for visualization of multidimensional patterns to two dimensions using data sets from odor sensing system. We conclude the combination technique has shown more advantages comparing with the PCA and Sammon nonlinear technique individually.

• 디지털융복합연구
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• 제14권4호
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• pp.251-258
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• 2016

빅 데이터 처리는 데이터의 크기나 복잡도가 커서 기존의 전통적인 데이터 처리 기법으로는 다루기 힘든 데이터의 처리를 의미한다. 싱글보드 컴퓨터를 포함하는 스마트 기기의 보급은 데이터를 처리하는 방법에 많은 영향을 미치고 있으며 이 들을 활용하여 데이터를 처리하는 기법에 대한 연구가 진행되고 있다. 본 연구에서는 빅 데이터 처리에 필요한 분산처리 시스템을 데스크톱 기기 환경이 아니라 라즈베리파이를 활용하여 하둡 분산처리 환경을 구축하는 방안을 제시한다. 또한 제안하는 시스템의 다양한 테스트를 통한 성능 분석과 스케일링의 용이성을 통해 구축한 학습 환경 구성의 효율성을 보인다.

• Journal of Computational Design and Engineering
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• 제2권3호
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• pp.183-194
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• 2015

This paper proposes a novel method for visualizing the thickness and clearance of 3D objects in a polyhedral representation. The proposed method uses the distance field of the objects in the visualization. A parallel algorithm is developed for constructing the distance field of polyhedral objects using the GPU. The distance between a voxel and the surface polygons of the model is computed many times in the distance field construction. Similar sets of polygons are usually selected as close polygons for close voxels. By using this spatial coherence, a parallel algorithm is designed to compute the distances between a cluster of close voxels and the polygons selected by the culling operation so that the fast shared memory mechanism of the GPU can be fully utilized. The thickness/clearance of the objects is visualized by distributing points on the visible surfaces of the objects and painting them with a unique color corresponding to the thickness/clearance values at those points. A modified ray casting method is developed for computing the thickness/clearance using the distance field of the objects. A system based on these algorithms can compute the distance field of complex objects within a few minutes for most cases. After the distance field construction, thickness/clearance visualization at a near interactive rate is achieved.

• 가족자원경영과 정책
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• 제4권1호
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• pp.95-111
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• 2000

The family financial management is the important element which has a effect on the improvement of family economic well-being. Thus the study sets up human & material resources and requirement as an input factor, family financial management as an throughput factor, and economic well-being as an output factor, and then identifies if there are some relationships among them by using a systematic approach of family financial management. The questionaires were distributed to 600 employed wives by carrying out cluster sampling and disproportional stratified sampling. The 573 cases of them were used as the mean, ratio, Pearson’s Correration, ANOVA, factors analysis, and Stepwise Regression using the SAS/PC+. The major findings of the study are as follows: 1) A practical application of information as on input variable, appears the fator which has an important effect upon the throughput factor, that is, family financial management. The employed wives should manage a lot of resources in rapidly changing social-economic circustances. So it shows that not only they should take informations open to their daily life and then make practical use of them in managing their family finance, but also they must be capable of judging and accepting reasonable informations in order to gain and manage resources suitable to the characteristics of family finance and family members’need. 2) There was significant relationship between the employed wives’family financial management and family economic well-being, focused on the systematic theory of family financial management. This study provides for the information to develope the program for the employed wives’family financial planning and counseling.

• Earthquakes and Structures
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• 제9권5호
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• pp.957-981
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• 2015

Earthquakes occur as a cluster in many regions around the world where complex fault systems exist. The repeated shaking usually induces accumulative damage to affected structures. Damage accumulation in structural systems increases their level of degradation in stiffness and also reduces their strength. Many existing analytical tools of modeling RC structures lack the salient damage features that account for stiffness and strength degradation resulting from repeated earthquake loading. Therefore, these tools are inadequate to study the response of structures in regions prone to multiple earthquakes hazard. The objective of this paper is twofold: (a) develop a tool that contains appropriate damage features for the numerical analysis of RC structures subjected to more than one earthquake; and (b) conduct a parametric study that investigates the effects of multiple earthquakes on the response of RC moment resisting frame systems. For this purpose, macroscopic constitutive models of concrete and steel materials that contain the aforementioned damage features and are capable of accurately capturing materials degrading behavior, are selected and implemented into fiber-based finite element software. Furthermore, finite element models that utilize the implemented concrete and steel stress-strain hysteresis are developed. The models are then subjected to selected sets of earthquake sequences. The results presented in this study clearly indicate that the response of degrading structural systems is appreciably influenced by strong-motion sequences in a manner that cannot be predicted from simple analysis. It also confirms that the effects of multiple earthquakes on earthquake safety can be very considerable.

• 한국의류학회지
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• 제21권3호
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• pp.559-570
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• 1997

The purpose of this study was to investigate consumer shopping orientation toward foreign brands in the context of clothing involvement, ethnocentrism, country-of-orion effects and demograpic variables. But in this paper, to begin with, shopping orientation was studyed in connection with ethnocentrism and country-of-orion effects. The questionnaire was distributed to 300 female consumers over twenties living in pusan area and finally 213 data sets were used for statistical analysis.8y factor analysis,5 shopping orientation factors were identified: following to foreign brands, desire for flaunt, preference to domestics, favor to foreign brands and country-of-orion consciousness. By univariate analysis, consumer's disposition of ethnocentrism was studyed and consumers were divided into 3 groups according to disposition of ethnocentrism through fast cluster analysis. Resurts reveled that Korean consumers have strong ethnocenterism. And country-of-orion effects were studyed. Consumers are favorable toward foreign brands and products, especially toward Italy and France goods, except Hongkong and China goods nevertheless strong ethnocentrisuL As a result of canonical correlation analysis about shopping orientation factors and ethnocenterism revealed that ethnocenterism correlated negatively with one factor (following to foreign brands) and positively with another (preference to domestics).