• Journal of the Korean Society for Nondestructive Testing
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• v.23 no.3
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• pp.220-226
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• 2003

This paper presents the result of an investigation on the application of the acoustic emission method to the monitoring of fatigue crack initiation, growth and track location in welded joints. Fatigue test was carried out for a typical fillet welded joint of ship structure. AE parameter such as ring down count was analyzed in time domain and crack locations were examined by source location and cluster option which is one of the functions of AE signal processor The usability of AE mettled was confirmed for the detection of the initiation and location of through crack.

• Horticultural Science & Technology
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• v.19 no.2
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• pp.159-162
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• 2001

The genetic relationships of Korean native Orostachys species collected from various regions were analysed using random amplified polymorphic DNA (RAPD) method. Eighteen Orostachys species analysed with UPGMA were clustered into three groups A, B, and C. However, four species were not clustered into any group. O. iwarenge species in group A (No. 18-No. 22) showed low similarity with 66.3-73.9% according to the cluster analysis. O. malacophyllus species in group B (No. 12-No. 17) showed low similarity with 66.7-83.7% according to the cluster analysis. The similarity coefficient value of O. japonicus (No. 3-No. 8) except Anmyeondo collected variety (No. 9) showed higher level with 84.2-92.3% than O. iwarenge or O. malacophyllus. Therefore, O. japonicus is thought to be genetically stable, and have less regional variation.

• Journal of the Korean Society for Library and Information Science
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• v.43 no.3
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• pp.399-416
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• 2009

In this study, clustering methods with related tags were discussed for improving search and exploration in the tag space. The experiments were performed on 10 Delicious tags and the strongly-related tags extracted by each 300 documents, and hierarchical and non-hierarchical clustering methods were carried out based on the tag co-occurrences. To evaluate the experimental results, cluster relevance was measured. Results showed that Ward's method with cosine coefficient, which shows good performance to term clustering, was best performed with consistent clustering tendency. Furthermore, it was analyzed that cluster membership among related tags is based on users' tagging purposes or interest and can disambiguate word sense. Therefore, tag clusters would be helpful for improving search and exploration in the tag space.

• Journal of Korean Academy of Fundamentals of Nursing
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• v.13 no.2
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• pp.304-311
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• 2006

Purpose: This study was done to examine the relation of self-reported adult attachment style, perceived parental rearing styles and anger in undergraduate students. Method: The six hundred and fifty undergraduate students participating in this descriptive correlational design study were conveniently sampled from K University and S College located in Seoul, Korea. The instruments were Spielberger's state-trait anger expression inventory - Korean version(Chon, Han, Lee & Spielberger, 1997), the instrument for measuring attachment styles by Hazen and Shaver (1987), and Hong's instrument for measuring parental rearing style(2001). Data were analyzed by descriptive statistics, t-test, $X^2-test$, ANOVA, and cluster analysis using pc-SAS(version 8.0e) program. Results: The mean scores for trait anger and anger-in were higher in undergraduate students with insecure and ambivalent attachment style compared to students with a secure attachment style. The mean score for anger-control was highest in undergraduate students with a secure attachment style. The parental rearing styles by cluster analysis were grouped as Neglect, Permissive, Democratic, and Protective-control. The mean scores for trait anger, anger-in, and anger-out were higher in undergraduate students with 'Neglect' parental rearing style than in those with 'Democratic' and 'Protective-control' rearing styles. Conclusion: Trait anger and anger expression might be related to an attachment style and/or a parental rearing style.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.12 no.5
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• pp.942-947
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• 2008

A cluster server usually consists of a front end node and multiple backend nodes. Though increasing the number of bookend nodes can result in the more QoS(Quality of Service) streams for clients, the possibility of failures in backend nodes is proportionally increased. The failure causes not only the stop of all streaming service but also the loss of the current playing positions. In this paper, when a backend node becomes a failed state, the recovery mechanisms are studied to support the unceasing streaming service. The basic techniques are hewn as providing very high speed data transfer rates suitable for the video streaming. However, without considering the architecture of cluster-based VOD server, the application of these basic techniques causes the performance bottleneck of the internal network for recovery and also results in the inefficiency CPU usage of backend nodes. To resolve these problems, we propose a new failure recovery mechanism based on the pipeline computing concept.

• Bulletin of the Korean Chemical Society
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• v.21 no.7
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• pp.720-726
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• 2000

The analytic gradient method for the equation-of-motion coupled-cluster singles and doubles (EOM-CCSD) energy has been extended to employ a reduced molecular orbital (MO) space. Not only the innermost core MOs but also some of the outermost virtua l MOs can be dropped in the reduced MO space, and a substantial amount of computation time can be reduced without deteriorating the results. In order to study the magnitudes and trends of the effects of the dropped MOs, the geometries and vibrational properties of the ground and excited states of BF, CO, CN, N2, AlCl, SiS, P2, BCl, AIF, CS, SiO, PN and GeSe are calculated with different sizes of molecular orbital space. The 6-31 G* and the aug-cc-pVTZ basis sets are employed for all molecules except GeSc for which the 6-311 G* and the TZV+f basis sets are used. It is shown that the magnitudes of the drop-MO effects are about $0.005\AA$ in bond lengths and about 1% on harmonic frequencies and IR intensities provided that the dropped MOs correspond to (1s), (1s,2s,2p), an (1s,2s,2p,3s,3p) atomic orbitals of the first, the second, and the third row atoms, respectively. The geometries and vibrational properties of the first and the second excited states of HCN and HNC are calculated by using a drastically reduced virtual MO space as well as with the well defined frozen core MO space. The results suggest the possibility of using a very smalI MO space for qualitative study of valence excited states.

• Korean Journal of Social Welfare Studies
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• v.49 no.1
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• pp.163-190
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• 2018

The citizen-initiative has been frequently mentioned in community building project which is being promoted by Seoul City. The citizen-initiative has become an important concept in the direction of community welfare efforts. However, this concept has not been defined clearly in social welfare. In this context, the purpose of this study is to find how the practitioners of the social welfare practice field recognize the concept of citizen-initiative. In this study, concept mapping method was used to generate 59 statements about the citizeninitiative in 10 social workers in Seoul. Multidimensional scaling analysis and hierarchical cluster analysis are used to do mapping and grouping the 59 statements. The results are as follows. A total of 6 categories were derived. The six categories are named "Inducement of Participation", "Practice", "Procedure", "Awareness and Interest extension", "Expression of Opinion", "Attitude and Emotion". "Practice" category was revealed as a core category in the concept of citizen-initiative. This study is meaningful as a first step to discuss "what is the citizen-initiative?" and to make consensus in social welfare academic area and practice field.

• Korean Journal of Remote Sensing
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• v.34 no.6_1
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• pp.1067-1087
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• 2018

In a study for LiDAR data based building boundary extraction, usually dense point cloud was used to cluster building rooftop area and extract building outline. However, when we used DSM generated from stereo image matching to extract building boundary, it is not trivial to cluster building roof top area automatically due to outliers and large holes of point cloud. Thus, we propose a technique to extract building boundary semi-automatically from the DSM created from stereo images. The technique consists of watershed segmentation for using user input as markers and recursive MBR algorithm. Since the proposed method only inputs simple marker information that represents building areas within the DSM, it can create building boundary efficiently by minimizing user input.

• Women's Health Nursing
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• v.25 no.3
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• pp.315-328
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• 2019

Purpose: The purpose of this study was to explore the components and nature of happiness in middle-aged women in Korea. Methods: Thirty middle-aged women living in metropolitan Seoul and Gyeonggi and Chungcheong provinces agreed to participate in this study. The data were collected through in-depth interviews with the participants in one-on-one settings. The data were analyzed qualitative using Colaizzi's method of phenomenology. Results: The three theme clusters were extracted from the raw data, along with 13 themes and 138 meaningful sentences and phrases. The three happiness theme clusters in middle-aged women were "live healthy for stability," "rule one's mind for harmony," and "activate hopes for self-esteem." The first theme cluster included healthy life, economic stability, physical youth, and positive thought. The second theme cluster included that harmonious family, ruling of mind, my position as invisible person in social relationships, and precious relationships to support. The last theme included the center of one's life is oneself, a sense of accomplishment, self-improvement, recognition of one's worth and rest for one self. The three theme clusters were associated with the existence, relatedness, and growth (ERG) of ERG areas, respectively. Conclusions: We conclude that the core components of happiness in middle-aged women are to live healthy and mind-ruled and activate hope. The nature of happiness is egocentric stability in middle-aged women. The results suggest that theme clusters might be used to develop a scale for measuring happiness in middle-aged women. This will be helpful to assess the psychosocial status of middle-aged women in Korea.

• Journal of Digital Convergence
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• v.17 no.8
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• pp.439-446
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• 2019

The purpose of this study is to analyze the relationship between social development and life satisfaction according to horse riding participation degree of participants. In order to accomplish the purpose of this study, participants of the equestrian program were set as the population and the sample was extracted by the method of Stratified cluster random sampling. The input data were statistically processed according to the purpose of the study using the SPSS / AMOS 22.0 Version Statistical Program for Windows, and the results were as follows. The results of the analysis are as follows. First, there were some differences in demographic characteristics such as horse riding experience, social development, life satisfaction, and participation level. Second, there was a partial relationship between participation level and social development of participants. Particularly, the degree of participation in horse riding experience was related to the activity of social development. Third, the participation level of horse riding experience was analyzed as having no direct influence on participants' life satisfaction. Fourth, it was analyzed that the development of sociality due to participation in horse riding experiences did not directly affect life satisfaction. Fifth, participation in experience of horse riding, social development and life satisfaction were not causally related.