• Title/Summary/Keyword: variance structure

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Measurements of Stress and Coping with Stress Among School-Aged Children in the Chon-buk Area (일부지역 초등학생의 스트레스와 대처행위 측정)

  • Chung, Young Sook;Chung, Seung Hee
    • Journal of the Korean Society of School Health
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    • v.9 no.2
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    • pp.185-195
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    • 1996
  • This study attempts to discover ways to prevent and cope with stress m primary school students, Specific, ally, we wish to investigate the sources of stress and to identify the variance and frequency of coping methods which have been used by the subjects. After examining the school children's list of items about stress and coping strategies by on open structure method, subjects ranked the seventy of stressor's and frequency of a coping strategies by closed structure method. A survey was done of 720 students who were from the 4th to 6th grade in 4 primary schools in the Chonbuk area from April 1st to May 30th, 1995. The major results obtained from this study were the following. 1. The sources of stress bad were classified in 57 items Among the 57 items, 'were school records' 'illness of parents' 'death of family members' 'meetings with trouble makers' ranked high ranking in the stress ratings. 2. Severity of stress. the mean total stress scores were 186.4 with 285 as the highest score. 3. The kinds of coping with stress using were classified in 35 items, Among the 35 items, 'wandering and walking alone' 'mood getting out of the in any way' 'trying to forget the stressor' 'were among the highest scored. 4. Frequency of coping with stress: mean total stress coping scores were 67.9 with 140 as the highest score. 5. Difference m stress and coping strategies between sex, age, living district and religion groups were examined. 1) Significant variables influencing stress scoring were sex (t=-2,29, p<.001) and grade (F=6.33, p<.001). 2) Significant variables influencing stress coping practice were residence (t=1.94, p<.05), sex (t=-3.17, p<.002) and religion (F=5,95, p<.0001).

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The Effect of Etching Time on the Biaxial Flexural Strength of IPS Empress® 2 Ceramic (불산 처리 시간이 IPS Empress® 2 세라믹의 2축 굴곡강도에 미치는 영향에 대한 연구)

  • Kim, Youn-Hwi;Shin, Soo-Yeon;Cho, In-Ho;Lee, Joon-Seok
    • Journal of Dental Rehabilitation and Applied Science
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    • v.23 no.4
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    • pp.269-281
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    • 2007
  • Fluoric acid etching is an essential procedure in cementation of reinforced ceramics to tooth surface. But there have been few studies about the changes of surface structure and flexural strength of IPS $Empress^{(R)}$ 2 ceramic according to the etching time. The objectives of this study were to examine the surface structure changes and the difference in biaxial flexural strength of IPS $Empress^{(R)}$ 2 ceramic according to various etching times. Sixty one disk-shaped specimens of IPS $Empress^{(R)}$ 2 ceramic($14mm{\times}1.2mm$) were fabricated for the biaxial flexural strength test and SEM analysis according to the manufacturer's recommendations. Sixty specimens were divided into 6 groups(n=10) according to the time of HF acid etching(0, 20, 180 and 300s)and silane/resin cement application. Each disk was loaded using a piston-on-3 ball biaxial configuration in a universal testing machine. The failure loads(N) were recorded, and the biaxial flexural strength for each disk was calculated. A one-way analysis of variance and independent t-test on transformed fracture strength data were used to determine significant differences between groups. The groups of no cementation showed a trend toward progressive weakening with increasing the etching time. However, this was not statistically significant at p=0.05 level. The groups of resin cementation exhibited no apparent trend in their mean strength values. SEM photomicrographs showed very different results of etching. Within the conditions of this study, alteration of surface topography by acid etching does not have a deleterious effect on the biaxial flexural strength of IPS $Empress^{(R)}$ 2 ceramic.

Construct Validity of Korean Translated Gifted Rating Scale (한국어판 Gifted Rating Scale의 구인타당도)

  • Lee, Dong-Hyuck
    • Journal of Gifted/Talented Education
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    • v.20 no.2
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    • pp.595-619
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    • 2010
  • This study examined the construct validity of a Korean translated version of the Gifted Rating Scales-School Form (GRS-S). Data were collected from five elementary schools in a metropolitan area and a midsize town in South Korea. Confirmatory factor analysis results indicated that the original factor structure (6-factor solution) fit the data collected from the teachers. However, the 6-factor solution did not fit the data collected from the parents. Thus, exploratory factor analysis was conducted for the parent data. The results showed that seven factors were extracted, and the factors explained 71.96% of the total variance. Unlike the original factor structure, some items of the academic ability scale were grouped with intellectual ability scale, and a creativity scale item and another academic ability scale item were an independent factor. The study outcomes provide preliminary support for a translated version of the GRS-S with elementary students in Korea. More detailed interpretations and implications of the results are discussed in the study.

Structure-Activity Relationships of Fungicidal N-Substituted Phenyl 1,3,5- Trimethylpyrazole-4-carboxamides in the Inhibition of Succinate Dehydrogenase (SDH) Isolated from Rhizoctonia solani $K{\ddot{u}}hn$ (벼 잎집무늬 마름병균 (Rhizoctonia solani $K{\ddot{u}}hn$)에서 분리한 Succinate Dehydrogenase (SDH) 에 대한 N-치환 phenyl 1,3,5-trimethylpyrazole-4-carboxamide 유도체의 효소활성저해)

  • Kim, Yong-Whan
    • Applied Biological Chemistry
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    • v.40 no.5
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    • pp.447-450
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    • 1997
  • Eighteen N-substituted phenyl 1, 3, 5-trimethylpyrazole-4-carboxamides were synthesized to screen for their mycelial growth inhibition activity against Rhizoctonia solani $K{\ddot{u}}hn$ $(pEC_{50})$ and to measure enzymatic inhibition activity of these compounds $(pI_{50})$ against succinate dehydrogenase (SDH) isolated from Rhizoctonia solani $K{\ddot{u}}hn$ A structure-activity relationship formulated by regression analysis showed that 79% of the variance in mycelial growth inhibition activity can be explained with SDH inhibition activity and chromatographic capacity factor $(\acute{k})$ as a hydrophobic parameter related to the penetration and transport processes in the biological system.

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Quantitative structure-activity relationship of N-substituted phenyl 5-chloro-1,3-dimethylpyrazol-4-carboxamides (N-치환 phenyl 5-chloro-1,3-dimethylpyrazole-4-carboxamide의 정량적구조활성상관관계)

  • Kim, Yong-Whan;Park, Chang-Kyu
    • Applied Biological Chemistry
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    • v.35 no.5
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    • pp.382-388
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    • 1992
  • Mycelial growth inhibition activity of forty-one N-substituted phenyl 5-chloro-1,3-dimethylpyrazole-4-carboxamides against Rhizoctonia solani was analysed quantitatively by multiple regression analysis using physicochemical parameters of substituents as independent variables and $pEC_{50}$ as dependent variable. As a result, a quantitative structure-activity relationship was formulated using eight physicochemical parameters, which explains 83% of variance of the fungicidal activity. The most important parameter for the biological activity was log k', as related to the penetration and transport processes in the biological system. The activity also correlated with other hydrophobic parameters$({\pi}_2,\;{\pi}_3)$, an electronic parameter$({\Sigma}{\sigma})$, and steric parameters$(STERIMOL\;parameters\;L_3,\;L_4)$.

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Studies on the properties of electrochromic films and the effect of migration barrier (Electrochromic 막의 특성과 물질이동 방지막의 효과에 대한 연구)

  • 황하룡;백지흠;허증수;이덕동;임정옥;장동식
    • Journal of the Korean Vacuum Society
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    • v.9 no.3
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    • pp.221-226
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    • 2000
  • After manufacturing the electrochromic device (structure: ITO glass/$WO_3$/electrolyte/$V_2O_5$/ITO;glass) by using of sol-gel process and evaporation, optical properties and migration effect were investigated. The result shows that electrochromic device with heat treated (at water vapor ambient, $500^{\circ}C$, 1 hour) sol-gel coated $WO_3$ and $V_2O_5$ films had the highest transmittance variance. Electrochromic devices are based on the reversible insertion of guest atoms into structure of the host solid. But after cyclic operation, we find that the tungsten in $WO_3$ film and the indium in ITO film were migrated with each other. For the purpose of blocking migration, tungsten barrier film is inserted between ITO and $WO_3$ film. The result of cyclic voltamogram and the Auger depth profile show that the peak separation of cyclic voltamogram is reduced to below 1/10 and we could effectively block the indium and tungsten migration that is caused by flow of Li ions.

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Molecular analysis of genetic diversity, population structure, and phylogeny of wild and cultivated tulips (Tulipa L.) by genic microsatellites

  • Pourkhaloee, Ali;Khosh-Khui, Morteza;Arens, Paul;Salehi, Hassan;Razi, Hooman;Niazi, Ali;Afsharifar, Alireza;Tuyl, Jaap van
    • Horticulture, Environment, and Biotechnology : HEB
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    • v.59 no.6
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    • pp.875-888
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    • 2018
  • Tulip (Tulipa L.) is one of the most important ornamental geophytes in the world. Analysis of molecular variability of tulips is of great importance in conservation and parental lines selection in breeding programs. Of the 70 genic microsatellites, 15 highly polymorphic and reproducible markers were used to assess the genetic diversity, structure, and relationships among 280 individuals of 36 wild and cultivated tulip accessions from two countries: Iran and the Netherlands. The mean values of gene diversity and polymorphism information content were 0.69 and 0.66, respectively, which indicated the high discriminatory power of markers. The calculated genetic diversity parameters were found to be the highest in wild T. systola Stapf (Derak region). Bayesian model-based STRU CTU RE analysis detected five gene pools for 36 germplasms which corresponded with morphological observations and traditional classifications. Based on analysis of molecular variance, to conserve wild genetic resources in some geographical locations, sampling should be performed from distant locations to achieve high diversity. The unweighted pair group method with arithmetic mean dendrogram and principal component analysis plot indicated that among wild tulips, T. systola and T. micheliana Hoog exhibited the closest relationships with cultivated tulips. Thus, it can be assumed that wild tulips from Iran and perhaps other Middle East countries played a role in the origin of T. gesneriana, which is likely a tulip species hybrid of unclear origin. In conclusion, due to the high genetic variability of wild tulips, they can be used in tulip breeding programs as a source of useful alleles related to resistance against stresses.

A Study on the Factors Influencing the Learning Satisfaction of Records Management Cyber Education (기록물 사이버교육의 학습만족도 향상을 위한 영향 요인 연구)

  • Na, Kyeongwon;Chang, Wookwon
    • Journal of Korean Society of Archives and Records Management
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    • v.22 no.1
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    • pp.61-82
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    • 2022
  • This study aims to investigate the factors influencing the learning satisfaction of records management cyber education that is opened and operated by the National Archives of Korea, as well as to improve the quality of cyber education program. Cyber education consisted of an introductory course, an intensive course, and a liberal arts course. As the major factors for learning satisfaction, "validity of content structure, interaction between professors and learners, learning motivation, active learning attitude, ease of use environment, and level of organizational support" were set. An online survey was conducted on the learning satisfaction according to the curriculum of each course. The survey was conducted to 107 institutions with specialized records management personnel, and additional in-depth interviews were also conducted. The survey analysis consisted of factor analysis, independent sample T-test, analysis of variance (ANOVA), correlation analysis, and multiple regression analysis. As a result of the study, the factors influencing learning satisfaction were found in the order of interaction between professors and learners, learning motivation, and validity of content structure.

Characteristics of Wintering Bird Communities in the Moeyungyi Wetland Wildlife Sanctuary, Myanmar

  • Aung, Hsu Sandar;Kim, Hankyu;Lee, Yohan
    • Journal of Forest and Environmental Science
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    • v.38 no.3
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    • pp.195-206
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    • 2022
  • Gaining an understanding of bird communities in different habitat types is essential for the conservation of ecologically important habitats. Wetlands possess different types of habitats and provide an important environment for wintering waterbird communities. This study compares avian communities in five different habitat types in the Moeyungyi Wetland Wildlife Sanctuary (MWWS), Myanmar. From December 2014 to the first week of February in 2015, bird and habitat data were collected from representative areas of five habitat types (i.e., short grassland, tall grassland, lotus fields, open water areas, and rice fields) at MWWS. We established nine sampling plots in each habitat type, and used the point quadrat method to survey habitats and the point count method to survey birds in the habitats. Simple one-way analysis of variance (ANOVA) and post-hoc tests were used to determine differences between bird communities. We made 95 detections during 19 daily visits to each of the five habitat types. During the survey period, we recorded a total of 10,389 individuals belonging to 52 different bird species, based on 7-min observations at each of the 45 point count stations. Furthermore, we detected significant differences by habitat structure (i.e., vegetation coverage, height, and density; water depth; and plant species diversity) as well as bird communities (i.e., species richness, abundance, and diversity indices). In addition, the detailed analysis of 52 avian species revealed significant differences among 45 species with respect to the mean numbers of observed individuals in the survey habitats. The findings of this study revealed significant differences in the structure and composition of waterbird communities among the five assessed habitat types. Because natural marshes provide preferable habitats for a larger number and greater diversity of birds, relative to rice fields, natural marshes should be prioritized for conservation and restoration in Moeyungyi Wetland Wildlife Sanctuary.

Analysis of genetic differentiation and population structure of the Korean-peninsula-endemic genus, Semisulcospira, using mitochondrial markers

  • Eun-Mi Kim;Yeon Jung Park;Hye Min Lee;Eun Soo Noh;Jung-Ha Kang;Bo-Hye Nam;Young-Ok Kim;Tae-Jin Choi
    • Fisheries and Aquatic Sciences
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    • v.25 no.12
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    • pp.601-618
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    • 2022
  • The genus Semisulcospira is an economically and ecologically valuable freshwater resource. Among the species, Semisulcospira coreana, Semisulcospira forticosta and Semisulcospira tegulata are endemic to the Korean peninsula and Semisulcospira gottschei is widespread in Asia. Therefore, maintenance and conservation of wild populations of these snails are important. We investigated the genetic diversity and population structure of Semisulcospira based on the mitochondrial cytochrome c oxidase subunit I (COI), NADH dehydrogenase subunit 4 (ND4), and combined mitochondrial DNA (COI + ND4) sequences. All four species and various genetic makers showed a high level of haplotype diversity and a low level of nucleotide diversity. In addition, Fu's Fs and Tajima's D neutrality tests were performed to assess the variation in size among populations. Neutrality tests of the four species yielded negative Fu's Fs and Tajima's D values, except for populations with one haplotype. The minimum spanning network indicated a common haplotype for populations of S. coreana, S. tegulata and S. gottschei, whereas S. forticosta had a rare haplotype. Also, genetic differences and gene flows between populations were assessed by analysis of molecular variance and using the pairwise fixation index. Our findings provided insight into the degree of preservation of the species' genetic diversity and could be utilized to enhance the management of endemic species.