• The Plant Pathology Journal
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• 제37권3호
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• pp.243-257
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• 2021

Bacillus pumilus is the causal agent of trunk bulges disease affecting rubber and rubberwood quality and yield production. In this study, B. pumilus and other closely related species were included in B. pumilus group, as they shared over 99.5% similarity from 16S rRNA analysis. Multilocus sequence analysis (MLSA) of five housekeeping genes and repetitive elements-based polymerase chain reaction (rep-PCR) using REP, ERIC, and BOX primers conducted to analyze the diversity and systematic relationships of 20 isolates of B. pumilus group from four rubber tree plantations in Peninsular Malaysia (Serdang, Tanah Merah, Baling, and Rawang). Multi rep-PCR results revealed the genetic profiling among the B. pumilus group isolates, while MLSA results showed 98-100% similarity across the 20 isolates of B. pumilus group species. These 20 isolates, formerly established as B. pumilus, were found not to be grouped with B. pumilus. However, being distributed within distinctive groups of the B. pumilus group comprising of two clusters, A and B. Cluster A contained of 17 isolates close to B. altitudinis, whereas Cluster B consisted of three isolates attributed to B. safensis. This is the first MLSA and rep-PCR study on B. pumilus group, which provides an in-depth understanding of the diversity of these rubber-pathogenic isolates in Malaysia.

• Restorative Dentistry and Endodontics
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• 제32권3호
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• pp.180-190
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• 2007

이 연구는 강화형 미세입자 복합레진인 Micronew에 Biscover 레진전색제를 적용한 후 칫솔마모시험을 시행하여 복합레진 표면의 조도와 현미경적 변화를 비교함으로써 레진전색제를 복합레진 표면에 재적용할 시기를 알아보고자 하였다. 분리 가능한 알루미늄 판과 복합레진을 이용하여 $8\times3\times2mm$ 크기의 복합레진 시편 200개를 제작하였다. 복합레진 시편의 양쪽표면을 Sof-Lex disc로 거친 입자에서 중간 입자까지 마무리한 후 실온의 증류수에 24시간 동안 보관하였다. 시편은 disc로 마무리만 시행한 F군 (n = 10)과 마무리 후 레진전색제인 Biscover를 적용한 B군 (n = 190)으로 분류하였다. B군은 다시 칫솔질을 가하지 않은 B-IM군 (n = 10)과 칫솔질을 가한 군 (n = 180, B-1군에서 B-18 군)으로 분류하였다. 칫솔질을 가한 군은 칫솔마모검사기의 수조에 페리오 치약과 증류수를 무게 비 50 : 50으로 혼합하여 부은 다음, 홈이 파진 알루미늄 블록에 각 군의 시편을 위치시키고 칫솔을 고정장치에 부착하여 전, 후 왕복운동을 가하여 칫솔질을 가하였다. 칫솔질은 B-1 군에서 B-18군 까지 각각 900회씩 증가시켜 16,200회 까지 시행하였다 표면조도측정기를 사용하여 각 군의 복합레진 표면의 평균 표면조도 값 (Ra)을 산출한 후 통계적으로 분석하였고, 주사전자현미경하에서 각 군의 대표적인 시편 1개를 관찰하여 다음과 같은 결과를 얻었다. 1. F군의 Ra는 $0.898{\pm}0.145{\mu}m$, B-IM군의 Ra는 $0.289{\pm}0.142{\mu}m$를 나타냈으며, B-1 군에서 B-18 군까지의 Ra는 점차적으로 증가하여 B-1 군에서 $0.299{\pm}0.48{\mu}m$, B-18 군에서 $0.642{\pm}0.313{\mu}m$까지 나타났다. 2. Ra 최종 군집중심은 군집 1 $(B-IM\simB-7)$에서 $0.361{\mu}m$, 군집 2 $(B-8\simB-14)$에서 $0.511{\mu}m$, 군집 3 $(B-15\simB-18)$에서 $0.624{\mu}m$를 나타내어 각 군집의 Ra 최종 군집중심 간에 통계학적으로 유의한 차이를 나타내었다. (F = 49.705, p = 0.000) 3. B-IM군의 Ra 증감율은 F 군에 비해 210.72%감소되었으며, B-8 군과 B-15군의 Ra 증감율은 B-IM군에 비해 각각 35.49%와 51.35% 증가되었다. 4. FE-SEM 관찰에서 B-IM 군은 매우 평활한 복합레진 표면을 나타내었고, B-8 군은 전체적으로 평활한 복합레진 표면을 보였지만 표면에 수직으로 아주 얕은 흠집을 나타내었다. B-15 군은 복합레진 표면의 중앙에서 B-8군보다 더 넓고 불규칙한 수직의 흠집을 나타내었고, B-18군은 복합레진 표면 전체에 넓은 흠집을 나타내었다.

• 한국가정과교육학회지
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• 제25권1호
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• pp.1-14
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• 2013

본 연구의 목적은 고등학생의 성장환경에 따라 진로의사결정에 차이가 있는가를 알아보는 것이다. 고등학생 600명을 대상으로 설문 조사를 실시하여 539부를 최종분석에 사용하여 성장환경 변인에 따라 군집분석을 실시하여 2개의 집단으로 구분하였다. 군집 A와 B는 성장환경에서 독립-성취 지향 요인을 제외하고 나머지 하위 요인의 점수에서 유의한 차이가 있어 성장환경의 특성이 서로 다른 집단임을 검증하였다. A group는 B group보다 정치적 사회적 지적 문화적인 활동에 관심을 갖고, 사회적 활동과 여가활동에 적극 참여하며 윤리적 도덕적 종교적 문제와 가치를 강조한다. 진로의사결정의 합리적 유형 점수는 A group보다 B group이 높고, 의존적 유형 점수는 A group이 B group보다 높다. 직업정보수집은 A group이 B group보다 점수가 높고, 목표설정과 자기평가 요인에서는 B group이 A group보다 점수가 높다. 성장환경의 특성에 따라 진로의사결정 유형과 자기효능감 점수는 차이가 있으므로 가정에서는 자녀에게 긍정적인 성장환경을 제공하는 것에 관심을 갖고 다양한 자극과 풍부한 경험이 제공되는 성장환경을 조성해 줌으로써 자녀들이 자신의 적성에 맞는 진로를 탐색하고 결정하는데 도움을 주어야 할 것이다.

• Membrane and Water Treatment
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• 제10권3호
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• pp.207-212
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• 2019

Non-aqueous solvents (NASs) are generally known to be barely miscible, and reactive with polar compounds, such as water. However, water can interact with some NASs, which can be used as a new means for water recovery from saline water. This study explored the fate of water and salt in NAS, when saline water is mixed with NAS. Three amine solvents were selected as NAS. They had the same molecular formula, but were differentiated by their molecular structures, as follows: 1) NAS 'A' having the hydrophilic group ($NH_2$) at the end of the straight carbon chain, 2) NAS 'B' with symmetrical structure and having the hydrophilic group (NH) at the middle of the straight carbon chain, 3) NAS 'C' having the hydrophilic group ($NH_2$) at the end of the straight carbon chain but possessing a hydrophobic ethyl branch in the middle of the structure. In batch experiments, 0.5 M NaCl water was blended with NASs, and then water and salt content in the NAS were individually measured. Water absorption efficiencies by NAS 'B' and 'C' were 3.8 and 10.7%, respectively. However, salt rejection efficiency was 98.9% and 58.2%, respectively. NAS 'A' exhibited a higher water absorption efficiency of 35.6%, despite a worse salt rejection efficiency of 24.7%. Molecular dynamic (MD) simulation showed the different interactions of water and salts with each NAS. NAS 'A' formed lattice structured clusters, with the hydrophilic group located outside, and captured a large numbers of water molecules, together with salt ions, inside the cluster pockets. NAS 'B' formed a planar-shaped cluster, where only some water molecules, but no salt ions, migrated to the NAS cluster. NAS 'C', with an ethyl group branch, formed a cluster shaped similarly to that of 'B'; however, the boundary surface of the cluster looked higher than that of 'C', due to the branch structure in solvent. The MD simulation was helpful for understanding the experimental results for water absorption and salt rejection, by demonstrating the various interactions between water molecules and the salts, with the different NAS types.

• 한국지역지리학회지
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• 제22권2호
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• pp.397-410
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• 2016

본 연구는 국가주도형으로 조성된 대표적인 산업집적지인 구미 IT 클러스터의 내생적 발전 가능성을 탐색하기 위해서 2005년부터 추진되어 온 산업단지 혁신클러스터정책의 미니클러스터 사업에 대하여 심층 고찰한 것이다. 구미 IT 클러스터를 구성하고 있는 산 학 연 주체들로 구성된 미니클러스터들은 관 주도의 외생적 조직으로 형성되었으나, 점차 자생적 조직화 과정을 거치면서 자율적인 학습 커뮤니티 조직으로 진화되는 모습을 나타내고 있다. 이를 통해 국지적 학습과 지식 공유가 활성화될 수 있는 사회적 자본의 축적과 국지적 뿌리내림으로 참여기업들뿐만 아니라 지역 기업들의 경쟁력 강화에 기여한 것으로 평가된다. 이러한 성과는 정부주도형으로 형성된 외생적 산업집적지가 대 다수를 차지하고 있는 한국의 산업집적지 활성화 정책 수립에 있어서 중요한 시사점을 제공한다. 특히 본 연구 결과는 미니클러스터 사업과 같이 자생적인 학습 커뮤니티 조직이 활성화될 수 있는 소프트웨어 중심의 클러스터 사업이 일관성 있게 추진될 필요가 있음을 강조한다.

• 한국의류학회지
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• 제29권5호
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• pp.637-648
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• 2005

The purpose of this study was to investigate the differences among internet and TV home-shopping perceived risk segments in regard to clothing shopping orientations and purchase intention. The subjects used for the study were 290 female consumers aged from 20 to 40 living in Seoul. The study used factor analysis, cluster analysis, ANOVA, Duncan test, and $\chi^2-test$. The results showed that the Internet and TV home-shopping perceived risks consisted of 9 factors: Products uncertainty risk, Internet shopping mall trust risk, account-related risk, delivery risk, social risk, size risk, exchange/return risk, TV watching-related risk, and price risk. The cluster analysis showed that there were five groups segmented: Size risk/TV watching risk group, Social risk/Internet trust risk group, Return risk/TV watching low-risk group, Delivery risk/product trust group, and Product risk group. The clothing shopping orientations were classified by 5 factors: Planned shopping, pleasure shopping, sales/fashion oriented shopping, time saving shopping, and credit card preference/in-store oriented shopping. The results showed that the five segmented perceived risk groups differed in regard to clothing shopping orientations, purchase intention, and demographics. Further group differences and implications of the results were discussed.

• 한국의류학회지
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• 제29권7호
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• pp.948-958
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• 2005

The purposes of this study were to segment adolescents into groups by family and school factors and to investigate the differences among the groups regarding body image and self-esteem. The study distributed the questionnaires to the adolescents who were middle and high school students in South Korea. The total respondents were 2240. The data were analyzed by factor analysis, cluster analysis, ANOVA, Duncan test, and $X^2-test$. Factor analysis showed that body image had four dimensions: appearance management, physical attractiveness, weight control, and the opposite sex fear. The cluster analysis showed that Korean adolescents were segmented into four groups (family preference/school preference group, family dissatisfaction/school dissatisfaction group, family average/peer competition group, family average/peer dissatisfaction group). The four groups were significantly different in regard to three dimensions of body image, self-esteem, and demographics. For example, the family preference/school preference group was most satisfied with their bodies, had a lowest opposite sex fear, and had a highest self·esteem. However, family dissatisfaction/teacher dissatisfaction group was most dissatisfied with their bodies, had a greatest interest in their appearance, and had a lowest self-esteem.

• 한국생활과학회지
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• 제19권1호
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• pp.157-165
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• 2010

The purpose of this study was to investigate the awareness and practices for diet according to the lifestyles of college students in Youngnam region. The data were collected by self-administered questionnaires during May 2007. One hundred-ninety samples were analyzed by SPSS Windows. Frequencies, Cronbach's alpha, factor analysis, cluster analysis, one-way analysis of variance, Duncan's multiple range test and chi-square test were conducted. The results were as follows. Lifestyles were categorized into four factors by factor analysis: popularity-seeking type, body-management-seeking type, convenience-seeking type and healthy-seeking type. In addition, the respondents belonged to one of four groups by cluster analysis: body-management-seeking group, popularity-seeking group, convenience-seeking group, and healthy-seeking group. There were significant differences in perception about individual body images, concern of diet, awareness of diet necessity and knowledge and practices for diet among the four groups. That is, the body-management-seeking group showed the highest levels of concern of diet, awareness of diet necessity and the practice of fasting therapy. Additionally, the healthy-seeking group showed the highest level of practice of exercise therapy.

• 한국의류산업학회지
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• 제7권6호
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• pp.650-656
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• 2005

The objective of this study is to analyze the formative attributes of face by measuring the shape and features of face. The faces of women in 20's were taken by digital camera and measured, then it has conducted a statistical analysis using a SPSS for factor analysis, correlation and cluster analysis. The findings are that it is consisted of six(6) different factors and it is responsible for 73.93%. In Factor 1 and Factor 2, it has explained the most significant factor to determine the shape of face. The result on cluster analysis is that it is classified into 5 groups and it is as follows. Attributes of each group is that Group 1 has a wide and long forehead, small and longish chin-line and chubby cheeks that represent polished and modern images, while Group 2 has small and longish forehead and chin-line that represent classical and mature images. On the other hand, Group 3 has a narrow forehead, small and longish chin-line and upward-style eyebrows that represents provocative images, whereas Group 4 has a shaped style that represent intellectual images and Group 5 has small and longish forehead and chin-line and cheekbones that represent polished and cute images.

• 한국학교ㆍ지역보건교육학회지
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• 제19권1호
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• pp.61-70
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• 2018

Purpose: The purpose of this study was to analyze the motivation of choosing a teaching profession, teacher efficacy, and satisfaction of teaching class of pre-health education teachers and compare the teacher efficacy, and satisfaction of teaching class by motivation of choosing a teaching profession group. Methods: The participants were 54 pre-health education teachers studying the teaching curriculum in 1 college located in S city. The collected data was analyzed with descriptive statistics, cluster analysis, ANOVA and Kruskal-Wallis using SPSS/WIN 21.0 program. Results: The average motivation of choosing a teaching profession, teacher efficacy, satisfaction of teaching class were above medium. After cluster analysis, 3 distinct groups emerged: motivation of choosing a teaching profession high group, motivation of choosing a teaching profession middle group, motivation of choosing a teaching profession low group. And the results showed significant differences in teacher efficacy, satisfaction of teaching class according to motivation of choosing a teaching profession group. Conclusion: The findings indicate that motivation of choosing a teaching profession affect the teacher efficacy, satisfaction of teaching class. Therefore It is necessary to identify the variables that influence motivation of choosing a teaching profession.