• Journal of the Korean Chemical Society
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• v.54 no.6
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• pp.711-716
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• 2010

New electroluminescent polymers with fluoro groups in vinylene units, poly(m-silylphenyl-p-phenylene-difluorovinylene) (m-SiP-PPDFV) have been synthesized by GILCH polymerization. These polymers have been used as the electroluminescent (EL) layers in single layer light-emitting diodes (LEDs) (ITO/PEDOT/polymer/Ca:Al). m-SiP-PPDFV shows PL around $\lambda_{max}$ = 452 nm and green EL around $\lambda_{max}$ = 497 nm. The current-voltage-luminance (I-V-L) characteristics of the polymers show turn-on voltages of 4.0 V approximately. Two fluoro groups were introduced on every vinylene units of m-SiP-PPV to give m-SiP-PPDFV in an attempt to increase the electron affinity of the parent polymer, and the devices show an increased color stability even with vinylene units. The color stability is attributed to the electron-withdrawing effect of the fluoro groups, which protect vinylene units from oxidation in PPV derivatives. We believe that fluoro groups can be introduced in vinylene units in order to attain excellent stability of PPV derivatives.

• Journal of the Korean Society of Tobacco Science
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• v.14 no.1
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• pp.24-32
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• 1992

The present study was conducted to compare the relative efficiency of two different haploid breeding methods in tobacco varietal development. A single F t hybrid plant from cross of two flue-cured cultivars of Nicotiana tabacum L., Bright Yellow4(BY4) and NC 95, was used to develop the 30 dihaploid lines by anther culture(F1-ADH) and maternally-derived doubled haploid utilizing Nicotiana africana(F1-MDH), respectively. As compared with mid-parent, ADH lines showed increasing in number of leaves, delaying in days to flower and narrowing in leaf width. However, no significant differences in the other characters investigated were recognized. MDH lines also showed narrow leaf width, while no significant differences in the other characters were observed. The variations of the characters investigated were generally greater in ADH than MDH lines. MDH lines had higher plant height and shorter days to flower than ADH lines, while other characters did not show remarkable differences. The degree of heritability for each of the characters observed between ADH and MDH was almost the same. The characters showing high heritability value were plant height, leaf number, days to flower, and yield, while those showing relatively low value were leaf length, leaf width, and total alkaloid content. Predicted gains from selection for increased yield were calculated for both populations(F1-ADH, F1-MDH) and correlated responses associated with selection for yield were estimated. Plant height, leaf width, days to flower, percent reducing sugar and disease resistance would be expected to improve with selection for yield much faster in the MDH population than in the ADH.

• Korean Journal of Childcare and Education
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• v.7 no.3
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• pp.125-141
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• 2011

This study investigates the mediation effects of trait anxiety in the relationships between reports by middle school adolescents in regards to self-differentiation and parents' marital conflicts. The participants were 252 middle school adolescents attended middle schools in Daegu or Gyeongbuk Province. The collected data were analyzed by Pearson's correlation, single and hierarchical multiple regressions, using SPSS 19.0. The results are as follows. (1) Parents' marital conflicts and trait anxiety were negatively associated with self-differentiation of middle school adolescents. (2) Trait anxiety was positively associated with parents' marital conflicts. (3) Trait anxiety exerted indirect effects on self-differentiation mediated by parents' marital conflicts.

• Korean Journal of Child Studies
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• v.24 no.1
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• pp.99-108
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• 2003

This study was based on theories of the culture of poverty and the causes and consequences of poverty. The strong relationship of family income to mother's education presents the possibility of an intergenerational education cycle. Using a longitudinal approach, parental poverty status was measured by family income, welfare assistance, single parent, and occupation when children were 2 years of age; children's school performance was measured by teacher reports of their reading, mathematics, writing, and overall ability at grade 1. Data were analyzed by structure equation modeling. Results showed that mother's pre-childbearing level of education predicted child school performance in grade 1, confirming an intergenerational cycle. In addition, the results indicated that parental poverty acts as a mediator between the cycle.

• Journal of the Korean housing association
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• v.24 no.5
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• pp.49-56
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• 2013

The goal of this research is to explore quantitative and residential features and spatial patterns of two-person households to suggest policy implications for housing supply and development in Seoul. Major findings of this study are as follows. First, the number of two-person households has increased rapidly mainly due to the growth of the elderly and single-parent households. They are mainly composed of the elderly over 60s and the youth of 30s of householder age. They are less likely to have well-paying jobs, and thus more likely to suffer from poverty. They are also inclined to live in rental and small-sized residential units and spatial segregation between the youth and the elderly became serious. In addition, their residential area can be classified into four types: area adjacent to employment centers, hinterland of urban centers, affordable multi-family housing area and redeveloped apartment area. It is necessary to change the current housing policy directions to take changing population and household structure into consideration. Also, diversified housing strategies and programs should be prepared to consider various household types and their needs and demands. Place-based strategies for housing supply and development are needed in consideration of spatial patterns and locational attributes of two-person households. Attention needs to be paid to resolving the social issue of residential segregation between different generations.

• The Journal of the Korea Contents Association
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• v.16 no.7
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• pp.566-574
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• 2016

The purpose of this study was to determine the viewing trends in eco-childhood education. Analyte is analyzed, such as from 10 March 2008 and 2015 annual target of 97 pieces of thesis until March trends, research content, research methods. As a result, first, the ecological childhood education subjects infant destination, Teachers, took place in indoor and outdoor environments subject, parent targeted net was a study of the most frequent targets 5 years of single age, 4 years old, 3 years old, It was a three-order. Second, the research method consisted of the most experimental studies. Third, research topics include ecology toddler exploring related variables of education, ecological infant was the most common educational programs academic and theoretical basis for the direction sought, ecological Early Childhood Curriculum understanding and national levels of the education process, linking childcare courses, ecology teacher education the program was in order. Fourth, training in experiential learning is the most common forest garden gardening had appeared, walking activities, ecology, art, spirituality, work, raise animals and plants, environmental education in order.

• Journal of The Korean Society of Grassland and Forage Science
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• v.17 no.1
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• pp.1-10
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• 1997

Unreduced (2n) gametes are meiotic products (pollen or egg) having a sporophytic (somatic) chromosome number, resulting from abnormalities during either microsporogenesis or megasporogenesis. They occur naturally at a low frequency in many plant species. Unreduced (2n) gametes in plants can be identified for four possible ways as follow i) pollen size and/or shape differences between haploid (n) and diploid (2n) pollen, ii) ploidy analysis (chromosome number) of progeny or meiotic analysis (presence of dyads andlor triads at the microspore stage), iii) progeny performance and fertility and iv) dosage of isozyme and DNA markers. Unreduced (2n) gametes can be an effective breeding tool in synthesizing new cultivars, providing a unique method to maximizing heterozygosity, i.e., transferring a large proportion of the non-additive genetic effects (intra- and inter- locus interactions) h m parent to offspring and can also be used to overcome infertility of interploidy crosses. Sexual polyploidization through 2n gametes has been a major route to the formation of naturally occurring polyploids. The three mechanisms of 2n pollen formation in potato have been discovered as follow: i) parallel spindles (ps) or tripolar spindles (ts), ii) premature cytokinesis (pc-I, pc-2) and iii) synaptic mutants (sy-2, sy-3, sy-4). Genetic analysis indicated that the mechanisms of 2n gamete formation were controlled by single recessive gene in potato, alfalfa, red clover, etc., and by two recessive genes in wheat. The use of 2n gametes which can efficiently transfer germplasm fiom wild relatives to cultivated species, especially fiom diploid to tetraploid could make a contribution to the improvement of germplasm base in breeding programs.

• Research in Plant Disease
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• v.11 no.2
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• pp.106-114
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• 2005

To breed powdery mildew resistant varieties, 104 accessions of Cucurbita spp. germplasm were evaluated. Powdery mildew resistance and horticultural characteristics of the accessions were investigated in the field conditions. C. martinezii was selected for high resistance to powdery mildew in the field. The growth of powdery mildew pathogen and response of leaf surface tissue to the pathogen were observed after artificial inoculation to resistant C martinezii and susceptible C. moschata cv. 'Wonye No.402'. Mycelium growth was very clearly different between resistant C. martinezii and susceptible C moschata cv. 'Wonye No. 402' at 5 days after inoculation at the adult stage. Interspecific hybridization was attempted to transfer powdery mildew resistance gene(s) from C. martinezii to C. moschata. A single dominant gene action was postulated as deter mining powdery mildew resistance at the seedling stage. But for the effective selection of powdery mildew resistant individuals, it was established that adult plant resistance should be confirmed in the field conditions after the seedling test. Through the seedling and field tests, C. moschata lines resistant to powdery mildew and superior to horticultural characteristics, were selected after 2 backcrossing and 3 selfing generations. The fruit characteristics of newly developed lines were similar to those of the recurrent parent, 'Jaechenjarae'.

• Structural Engineering and Mechanics
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• v.4 no.5
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• pp.553-568
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• 1996

Finite element stiffness matrix methods are presented for finding natural frequencies (or buckling loads) and modes of repetitive structures. The usual approximate finite element formulations are included, but more relevantly they also permit the use of 'exact finite elements', which account for distributed mass exactly by solving appropriate differential equations. A transcendental eigenvalue problem results, for which all the natural frequencies are found with certainty. The calculations are performed for a single repeating portion of a rotationally or linearly (in one, two or three directions) repetitive structure. The emphasis is on rotational periodicity, for which principal advantages include: any repeating portions can be connected together, not just adjacent ones; nodes can lie on, and members along, the axis of rotational periodicity; complex arithmetic is used for brevity of presentation and speed of computation; two types of rotationally periodic substructures can be used in a multi-level manner; multi-level non-periodic substructuring is permitted within the repeating portions of parent rotationally periodic structures or substructures and; all the substructuring is exact, i.e., the same answers are obtained whether or not substructuring is used. Numerical results are given for a rotationally periodic structure by using exact finite elements and two levels of rotationally periodic substructures. The solution time is about 500 times faster than if none of the rotational periodicity had been used. The solution time would have been about ten times faster still if the software used had included all the substructuring features presented.

• Korean Journal of Child Studies
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• v.2
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• pp.55-66
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• 1981

Research on children should be perferably made in reference with the past thinking if it is to be affirmed by the present and to predict the future. In this respect, Buddhism, which is one of the major original thinkings in the Orient as well as the most influential religion upon Koreans daily lives and attitudes, deserves to be researched in the light of education of children. In this thesis, I have made a trial to delve into the original Buddhistic scriptures to find out Buddha's outlook on home children and arrived at the following conclusions: 1. Concerning human development stages, Buddha regarded the starting point of human life from fertilization instead of birth, even at that ancient time, and the fetal life was devided into 4, 5, or 8 stages. 2. In spite of the numerous scriptures by Buddha, very little is written about children, and even these teaching did not regard the child as an independent entity. In addition, since Buddha was a person of superior enlightenment, he did not regard the age of human beings as of great importance. 3. On the relationship between parents and children, Buddha warned the extra ordinary attachment of parents toward children, because such attachment would be an obstacle in the search of truth. This idea was originated from his thought that the relationship between parents and children was not a single fixed one but of unlimited variation through numerous life times of reincarnation. This idea gives some illumination upon the problems of today's education where parent's exclusive attachment to their children and over-protection are hindrance for successful education. 4. Buddha put emphasis on parents' social duty, by which he meant that parents should care and accept not only their biological children but all children and all living things as if they were their own children. 5. Regardeding the children's role to their parents, Buddha taught that children should respect and support their parents under any condition. Buddha also emphasized that true filial piety was to help parents to improve their religious status by helping them attain the truth, morality, and wisdom. It is my intention to investigate Buddha's View tin children of entering pristhood.