• Bulletin of the Korean Chemical Society
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• v.35 no.11
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• pp.3199-3204
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• 2014

Two novel phosphorescent heteroleptic cationic Ir(III) complexes, Ir(bt)2(dmpe) (Ir1) and Ir (bt)2(dppe) (Ir2), where bt is 2-phenylbenzothiazole, dmpe is 1,2-bis(dimethylphosphino)ethane, and dppe is 1,2-bis(diphenyl-phosphino) ethane, were designed and synthesized. Their photophysical and electrochemical properties and the X-ray structure of the Ir1 complex were investigated. The prepared Ir(III) complexes exhibited blue-green emissions at 503-538 nm with vibronic fine structures in dichloromethane solution and PMMA film, implying that the lowest excited states are dominated by ligand-based $^3{\pi}-{\pi}^*$ transitions. The ${\pi}$-acceptor ability of the diphosphine ancillary ligand leads to blue-shift emission. The room temperature photoluminescent quantum yields (PLQYs) of Ir1 and Ir2 were 52% and 45%, respectively, in dichloromethane solution. These high PLQYs resulted from steric hindrances by the bulky cationic iridium complexes. The crystal structure of Ir1 was determined by X-ray crystallography, which revealed that central iridium adopted a distorted octahedral structure coordinated with two bt ligands (N^C) and one dmpe ligand (P^P) showing cis C-C and trans N-N dispositions. The bent nature of the dmpe ligand resulted in a relatively wide bite angle of $83.83^{\circ}$ of P-Ir-P.

• Journal of Welding and Joining
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• v.32 no.2
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• pp.48-53
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• 2014

This study was carried out to investigate the effect of postweld heat treatment(PWHT, 930, 1080, $1230^{\circ}C$) on the microstructure, phase formation, pitting corrosion and mechanical properties such as hardness, tensile strength and impact values of super duplex stainless steel(UNS S32750) multipass welds. Based on the microstructural examination and X-ray diffraction analysis, it was found that the ${\sigma}$ phase was formed in the welds heat treated at $930^{\circ}C$ in which the ferrite content greatly decreased into 5~10% in the welds. The secondary austenite was formed in the reheated zone of welds and redissolved into ferrite with increasing heat treatment temperatures. The tensile strength and impact values of welds heat treated at $930^{\circ}C$ were the lowest and revealed the brittle fracture surface. The weight loss by pitting corrosion increased with test temperatures. It was confirmed that pitting corrosion occurred mainly in secondary austenite of reheated zones. The postweld heat treatment temperature is recommended to be in the range of $1050{\sim}1150^{\circ}C$.

• Journal of The Korean Association For Science Education
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• v.11 no.2
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• pp.133-142
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• 1991

The purpose of this study is to develop a data base system for the information on research and development of science education. As the first step of this study and development, a classification system for the research and development materials was devised after discussing the process of science education and the research and development of science education. The classification system has nine main categories : 1. area, 2. subject, 3. behavior, 4. skill, 5. support, 6. type, 7. materials, 8. language, and 9. the others, each of which has one or two levels of subcategory. This classification system was revised and supplemented through the theoretical analysis by speci.diSts and the practical classification of master's theses and doctoral dissertations from the Department of Science Education, Seoul National University. But it still needs more revision and enlargement through the continuous application and analysis.

• Hwankyungkyoyuk
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• v.17 no.1
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• pp.43-56
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• 2004

The purpose of environmental education is to cultivate democracy citizens suitable for sustainable society. Suitable citizens for sustainable society are fostered person of environmental literacy, environmental sensibility, ecological and synthetic sights of environmental problems, decision making of environmental problems, and environmental responsibility etc. by environmental education. To achieve this purpose of environmental education effectively, it is desirable that produces and utilizes ICT(Information and Communication Technologies) works and methods that can show efficiently special sides(inter-relation, long-term effects etc.) of environmental problems. ICT environmental education materials and methods are raising the interest and participate of teenagers to environmental education because they are accustomed to the Internet in South Korea. Students can easily conversation with the person of similar interests and environment experts through cyber ICT environmental education. The directions of developing ICT teaching materials for environmental education to enforce self-directed learning, cooperation studying etc.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.14 no.11
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• pp.5601-5609
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• 2013

The purpose of this study is to figure out the application of perceived quality and authentication evaluation system of teaching materials and implements for children in the early childhood education field. To achieve this, a survey was carried out from April 20 to April 30, 2013 on 150 guidance teachers who teach children classes for more than 3 years at kindergartens in Daejeon area, Chungnam. The results of the analysis are as follows. First, for the use of teaching materials and implements, 96.1% of teachers thought the quality of teaching materials and implements in their interaction with children was important. Most of them had a high perception of the quantity and quality when using teaching materials and implements with early childhood curriculum. For the most inconvenience when using teaching implements, developmental appropriateness was the highest by 47.3%. And the convenience of the application to children was 3.54 points on average. Above this, the application of teaching implements to children when using play and teaching implements was useful by 3.89 points on verage. The current teaching materials and implements for children in the early childhood education field was normal by 3.29 points on average. Second, teachers' perception of teaching materials and implements was relatively positive by 3.99 points on average, proving that the quality of teaching materials and implements based on the application of teaching materials and implements to early children in kindergartens was very important. Consequently, considering the importance and usefulness of teaching materials and implements, it is necessary to introduce institutional policies that teaching materials and implements with quality standard and institution evaluation can introduce the evaluation authentication system to guarantee the convenience of children' safety and use by the supply of quality-guaranteed products.

• Journal of The Korean Association For Science Education
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• v.23 no.1
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• pp.1-8
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• 2003

The purpose of present study was to develop teaching-learning materials based virtual reality technology(VRT), and to examine the effect of it on the knowledge achievement of biology. Authoring tool of virtual reality(VR) was 3D Webmaster made in Superscape Ltd., United Kingdom. Educational materials was developed for the structure and function of eye of life field in the 10th science. It was learner-directed and interactive educational material using the Web-based and desktop VR. The result showed a meaningful improvement on the achievement. Using 3D VR shows the potential of available education media in the next generation as science teaching-aided materials, which especially was efficient in the understanding and perception of abstract or difficult to direct experience learning contents.

• Advances in nano research
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• v.15 no.3
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• pp.253-261
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• 2023

This study investigates the application of nano-composite materials in physical education, specifically focusing on improving the performance of sports hall flooring. The research centers on carbon nanotube reinforced polyvinyl chloride (PVC) composites, which offer enhanced mechanical properties and durability. The incorporation of carbon nanotubes as reinforcements in the PVC matrix provides notable benefits, including increased strength, improved thermal stability, electrical conductivity, and resistance to fatigue. The key parameters examined in this study are the weight percentage of carbon nanotubes and the temperature during the fabrication process. Through careful analysis, it is found that higher weight percentages of carbon nanotubes contribute to a more uniform dispersion within the PVC matrix, resulting in improved mechanical properties. Additionally, higher fabrication temperatures aid in repairing macroscopic defects, leading to enhanced overall performance. The findings of this study indicate that the utilization of carbon nanotube reinforced PVC composites can significantly enhance the strength and durability of sports hall flooring. By employing these advanced materials, the safety and suitability of physical education environments can be greatly improved. Furthermore, the insights gained from this research can contribute to the optimization of composite material design and fabrication techniques, not only in the field of physical education but also in various industries where composite materials find applications.

• Korean Journal of Community Nutrition
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• v.6 no.2
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• pp.234-242
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• 2001

This study was aimed at development of a nutrition education program, which was designed for children, their parents and personnel in preschool nursery facilities and carried out by dieticians. The program was conducted at 6 preschool nursery facilities for 3 months from July to September 1998. Four-hundred thirty-three children aged 2 to 7 years were engaged in the program. Children in each class were given nutrition education practice once a week by dieticians using education materials and a guide book based on a 12-week program. The themes of nutrition education for children consisted of 'knowledge of food sources and foods', 'relations between food and health', 'other roles of food', 'right eating habit', and 'cooking practice'. Each of five leaflets on nutrition education for parents was delivered eery three weeks in a series and leaflets were posted on a bulletin board. Nursery school teachers were educated by their participation in the class with dieticians using education materials. Evaluation of nutrition education by children, parents and personnel was carried out by interviewing and using questionnaires before and after the program. Children responded more positively more positively on their eating behavior and sanitary behaviors after nutrition education. Parents'opinions on the nutrition education program were positive : 72.3 described the nutrition education program as 'very good'and 'good'. In addition, 71.3% answered that the education materials for parents were helpful. A majority(93.8%) of personnel in facilities evaluated the nutrition education program effective. Nursery personnel evaluated the importance of general nutrition knowledge, childhood nutrition, and obesity control for nutrition management and nutrition education more highly after nutrition education. This study indicates that nutrition management and nutrition education programs for preschool nursery facilities are necessary and they would be effective when implemented by dieticians.

• Research in Community and Public Health Nursing
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• v.10 no.2
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• pp.494-507
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• 1999

This study has developed the sex education contents including new natural family plan, concept and principle by receiving the opinions and advices from professionals and professors on sex education, by amending and supplementing existing teaching materials on sex, and examining the books related with sex education contents that reflect the request of teachers and students, and the lack of sex education teaching materials which have been the reason that needs of school sex education has been highly recognized but not vitalized. The developed sex education contents are 8 areas such as knowing my body right, caring my body, observing the ability of being pregnant, marriage, sexual intercourse, process of pregnancy, miscarriage, and sexual violence, 30 lower areas, and 105 detailed contents in their composition, and here are the results of analyses of the degree of request of nurse teachers and the students on them. The teachers showed highest request in the area of sexual violence(M =4.67), the next was my body care(M=4.44), knowing my body right(M =4.38), process of pregnancy(M=4.13), marriage(M=4.11) and sexual intercoursen (M=3.98), ways of judging the ability of being pregnant(M=3.88), and miscarriage(M=3.72) showed comparative higher request than normal. Not like the teachers, the students showed that they requested Marriage area as the highest need(M=3.04) and next was sexual violence(M=3.02), caring my body(M=3.00) to have been higher than normal. Process of pregnancy(M=2.99), Sexual intercourse(M=2.81), miscarriage(M = 2.77), observation of the ability of being pregnant(M=2.74), and knowing my body right(M=2.70) have been the requests lower than normal. This study showed that sexual violence, marriage, caring my body, were the items most requested by both the leacgers and students and in elementary school the development of sex education teaching materials on natural family plan suitable to the level of development of the children has been requested as it has had no inclusion of the concept of natural family plan, and the students in elementary school are concerned on indirect sexual contents related with physical health like regular exercise rather than direct sexual education contents including sexual intercourse. All these show that they are still so naive on sex. The sense of the teachers on sex has been connected with the level of achievement of sex education of the children as it has been the important cause of deciding the contents of sex education. Therefore the materials developed onesidedly by leaders without reflecting the needs or the preference of the students might be worries of bringing shameful. low quality and negative opinions on sex, and on the other hand the children might lose the concerns and interest on sex education, So the materials should be developed to have the contents of sex education coinciding with the request of the children.

• Korean Journal of Community Nutrition
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• v.13 no.6
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• pp.818-828
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• 2008

This study was conducted to investigate actual conditions and needs on breastfeeding education for pregnant women in health centers for the development of a breastfeeding educational program. The questionnaires were mailed to 245 health centers and 148 (60.4%) questionnaires were returned. 91% of the health centers had breastfeeding education for pregnant women. 66% of them operated breastfeeding education as one part of other health programs. About 76% of supervisors and 64% of educators were the nurses. The teaching methods frequently used were lectures (30.5%), giving out booklets and leaflets (22.6%), demonstration and practice (21.5%), personal counseling (13.3%), and others. The teaching materials used were materials of outside speakers (39.7%), materials of development oneself (19.0%), materials of academic association or institute (14.8%), and others. The subjects which educators taught were the benefits of breastfeeding (16.7%), breastfeeding techniques (15.8%), caring for breasts before and after delivery (15.1%), nutritional management for lactating women (14.2%), coping strategies for the difficult situation of breastfeeding (13.3%), and others. Those were different from each other according to the educators' general characteristics. Success factors of education were increased motivation for breastfeeding (52.8%), practice (22.6%), professional's lecture (11.3%) and others. The failure factors of education were the ineffectiveness of the lecture method (69.2%), lack of education for supporters (15.4%) and lack of standardized education (15.4%). The most important barrier of education was the lack of a standardized breastfeeding educational programs (43.9%). The most effective teaching methods that educators thought were demonstration and practice (24.0%). The educators thought they need the tools and space for practice (28.2%), a standardized breastfeeding educational program (26.9%), and the human resources (24.4%) for effective education. Subjects that educators thought important for education were the breastfeeding techniques, benefits of breastfeeding, caring for breasts before and after delivery, nutritional management for lactating women, coping strategies for the difficult situation of breastfeeding, rooming system after delivery, ways to assess mother's milk quantity, introducing successful cases of breastfeeding in rank order. To promote the effectiveness of breastfeeding education, standardized breastfeeding educational programs, diverse teaching materials, space and tools, and human resources are needed.