• Journal of the Korean Wood Science and Technology
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• v.30 no.4
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• pp.8-16
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• 2002

This study was performed to produce the high reactive lignin zero substrates from autohydrolyzed wood resources. In chemical compositions of used raw-materials, there were significant differences between two species, Japanese larch (Larix leptolepis) and oak (Quercus mongolica) woods. Japanese larch contained 25 to 3.5 times higher amounts of extractives than oak wood, which is mainly derived from high content of arabinogalactan in Japanese larch wood. Oak wood has 5% lower lignin content and 3% higher holocellulose and pentosans than larch wood. Concerned to changes in wood components during autohydrolysis pretreatment at 22 kg/cm² steaming pressure for 5~60 min, glucose content was constant during pretreatment, while hemicellulose and lignin were abruptly changed. Hemicellulose fraction was decreased significantly and lignin contents increased because of its condensation reaction with hemicellulose degradation products. The pH of hydrolyzates during pretreatment was decreased, reached upto pH 3 and since then leveled off. In the case of oak wood, same tendency was observed as in Japanese larch. Autohydrolysis followed by sodium chlorite and sulfite or bisulfite pretreatment was very effective in delignification of the substrates. In particular, two-stage delignification of autohydrolyzed woods with alkali and O₂-alkali resulted in very low lignin content substrates, such as 0~0.2% lignin substrate.

• Journal of the Korean Society of Earth Science Education
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• v.15 no.3
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• pp.345-353
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• 2022

This study was conducted to investigate the effect of PBL applied environmental writing class on the climate literacy and environmental sensitivity of 43 5th grade students. To carry out this study, an environmental writing class that applied PBL in the 8th class was developed and applied to examine the effect. The conclusions of this study are as follows. First, the environmental writing class applying PBL had a statistically significant effect on improving the climate literacy of elementary school students. Statistically significant results were found in the cognitive and definitional domains, excluding the sub-domain of climate literacy. Second, the environmental writing class applying PBL has a significant effect on improving the environmental sensitivity of elementary school students. Statistically significant effects were found in all sub-domains of environmental sensitivity, sensitivity, aesthetic sense and emotional stability, and sympathy and compassion. The reason why the environmental writing class applying PBL was able to improve the climate literacy and environmental sensitivity of elementary school students is that students actively participate in the class to solve environmental problems and realize that environmental problems are deeply related to our real lives.

• Applied Chemistry for Engineering
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• v.34 no.2
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• pp.126-130
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• 2023

In response to environmental demands, pyrolysis is one of the practical methods for obtaining reusable oils from waste plastics. However, the waste plastic pyrolysis oils (WPPO) are consumed as low-grade fuel oil due to their impurities. Thus, this study focused on the upgrading method to obtain naphtha catalytic cracking feedstocks from WPPO by the hydroprocessing, including hydrotreating and hydrocracking reaction. Especially, various transition metal sulfides supported catalysts were investigated as hydrotreating and hydrocracking catalysts. The catalytic performance was evaluated with a 250 ml-batch reactor at 370~400 ℃ and 6.0 MPa H₂. Sulfur-, nitrogen-, and chlorine-compounds in WPPO were well eliminated with nickel-molybdenum/alumina catalysts. The NiMo/ZSM-5 catalyst has the highest naphtha yield.

• Journal of Practical Agriculture & Fisheries Research
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• v.20 no.1
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• pp.125-143
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• 2018

The study consisted of a survey of the residential satisfaction level of the 3rd grade students and a survey of accessibility from farms for practical field training to public facilities. According to the geographical location of the farms on the map, the average distance to facilities related to convenience or safety and health that students complained was about 12km. And that to social and public facilities was about 4.4km. Students pointed out the convenience of using transportation, commercial and convenient facilities, and the safety of anti-crime security facilities as complaints during the practice session. Residential satisfaction levels in five realms, such as facility and structure, convenience, safety, comfort and sociality, were not all reached at the satisfaction level. In particular, the satisfaction level of female students was sub-normal in the safety and convenience realms. The average satisfaction levels reviewed by department were sub-normal for horse industry and floriculture departments. By residential patterns, satisfaction with sharing with the farmers was higher than with other patterns. And satisfaction level by housing structure was much lower in the assembly and container structures Since residential satisfaction level is determined by the inside and outside environment of the dwelling, college should provide students with accurate and vivid data using information communication technologies.

• Journal of The Korean Association For Science Education
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• v.29 no.1
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• pp.43-53
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• 2009

The teacher's role in education is important. Science education majors must be able to solve problems effectively and pertinently when facing new ones in various situations and complicated human relations in order to become successful science teacher. The purpose of this research is to develop a test that measures the Practical Ability of pre-service science teachers and to apply this to them. The Practical Efficacy Scale for Science Education Majors was also developed in order to be used for validation. In this research, Practical Ability of Science Education Majors consisted of four sub-domains: subject education, business administration, relations and self-development. The result of the correlations between the scores of four sub-domains and the composite score of Practical Ability Test for Preservice Science Teacher(PATPST) is relevant. Subject education and administration business is the highest correlation with PATPSP score specially, and correlation between two areas appeared high. The result of applying PATPSP scores differed according to the grade of science education majors, but not according to their majors. This study's limitation is that the subjects consisted only of female students. However, PATPSP could be a new method that will help science education majors be successful science teachers.

• Journal of Acupuncture Research
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• v.18 no.4
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• pp.55-67
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• 2001

Objective : This study was performed to evaluate result of thoracolumbar compression fracture patient treated with Hua-Tuo-Jia-Ji-Xue(華佗夾脊穴) acupuncture. Methods : This clinical study was carried out 50 cases with thoracolumbar compression fracture, who had been admitted from January, 2000 to February, 2001, in the department of acupuncture and moxibustion, Hanseo University Oriental Medical Hospital. We divided two groups; A group, without using Hua-Tuo-Jia-Ji-Xue(華佗夾脊穴) acupuncture and the other group is B group, by using Hua-Tuo-Jia-Ji-Xue(華佗夾脊穴) acupuncture. Results : 1. The distribution of sex and age, 78% were female, and 84% were most above there sixties. 2. In the duration of symptom, the largest group was over 4 weeks. 3. In the distribution of cause, the largest group was "lifting heavy object"(32%) and the next was "slip down"(26%). 4. In the distribution of injured level was L1 body the most(19.6%) and T12 body was the next. 5. In the distribution of clinical symptoms on the admission, the largest group was lumbosacral pain(18%). 6. The result of treatment due to the duration of admission, 17case(34%) was the most above "Fair" during the 2~3 weeks. 7. The result of treatment, Good and Fair were the same in 24case(48%). 8. The duration of treatment was longer in high grade of clinical symptom. 9. B group discharged above good state 60% higher than A group.

• Journal of Korean Elementary Science Education
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• v.31 no.4
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• pp.541-557
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• 2012

Interest is acknowledged to be a critical motivational variable that influences learning and achievement. The purpose of this study was to investigate the interest of the elementary students when free inquiry activities were performed through a brain-based evolutionary scientific teaching and learning model. For this study, 106 fifth grade students were chosen and performed individually free inquiry activities. The results of this study were as follows: First, after free inquiry activities, as to free inquiry science related attitude, a statistically significant difference was not observed. But they came to have positive feelings about the free inquiry. Especially students marked higher mean score in openness showed consistency in sub-areas of free inquiry science related attitude. Second, students had interests in various fields, especially they had many interests in area of biology. They chose inquiry subjects that seems to be easily accessible from surrounding and as an important criterion of free inquiry they thought the possibility that they could successfully perform it. And students who belong to the high level in the science related attitudes and academic achievement diversified more topics. Third, most of students failed to further their topics. However, the students who specifically and clearly extended their topics suggested appropriate variables in their topics. On the other hand, students who couldn't elaborate their topics were also failed to suggest further topics and their performance of inquiry was more incomplete. In conclusion, the experiences of success in free inquiry make the science attitude of students more positive and help them extend their inquiry. These results have fundamental implications for the authentic science inquiry in the elementary schools and for the further research.

• Korean Journal of Community Nutrition
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• v.20 no.6
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• pp.399-410
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• 2015

Objectives: This study aims to identify self-resilience factors that drive right dietary and food safety practices in middle school students. Methods: Data was collected from 438 middle school students in Daegu using a self-administered questionnaire in December, 2013. The questionnaire consisted of 81 items with the following categories: general information, self-resilience, right dietary and food safety practices. Statistical analyses to determine frequency, average, ANOVA, factor analysis, reliability analysis, and regression analysis were performed using SPSS 21. Results: The results of factor analysis indicated that self-resilience was classified into challenge, adaptability, patience and achievement needs, and right dietary practices were sub-grouped into family meals, experience of dietary life, eco-friendly, balanced food, economy and bad food control, and food safety practices consisted of management of bacteria, hand washing and eating off a plate, safety food and food purchasing. The score of right dietary and food safety practices showed significant differences by sex, grade, and school achievement (p < 0.05). The economy factor of right dietary practices was significantly affected by the management of bacteria (p < 0.001), hand washing and eating off a plate (p < 0.001), safety food (p < 0.01), food purchasing of food safety practices (p < 0.05). The challenge factor of self-resilience significantly affected family meals, experience of dietary life, balanced food, economy, bad food control, management of bacteria, hand washing and eating off a plate, and safety food (p < 0.05). The adaptability factor of self-resilience was associated with factors such as eco-friendly, balanced food, economy, bad food control, management of bacteria, hand washing and eating off a plate, and food purchasing (p < 0.05). Conclusions: This study suggests that dietary education programs for middle school students could incorporate food safety practices, and self-resilience such as challenge, adaptability, patience and achievement needs to be effective.

• Journal of The Korean Association of Information Education
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• v.21 no.1
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• pp.97-104
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• 2017

This paper evaluates the appropriateness of the proposed robot education curriculum to consider conceptual understanding and learning activities model considering the curriculum and achievement criteria in order to make it easier to apply for a course in robot area. The professors of dept. of computer education at national universities of education reviewed the importance of education contents system and appropriateness of education period. Based on the results of the review, the conceptual elements and achievement standards of each sub-area were revised and supplemented, and then evaluated in three stages. Finally, the educational elements of the concept factors and achievement criteria were agreed upon. The proposed robotic computing education information systems and the achievement standards for schools in the area, as well as to match the grade level of the students without distinction variety of robots will be able to take advantage of computing education activities to reorganize the robot computing courses.

• Journal of The Korean Society of Integrative Medicine
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• v.5 no.4
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• pp.103-112
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• 2017

Purpose : This study was conducted to improve cognitive oral healthcare care by analyzing the correlation between oral health behavior and oral health status Korean adolescents. The subjects were 65,528 youths in 798 schools monitored in the Twelfth Korea Youth Risk Behavior Web-based Survey in 2016. Methods : The general characteristics consisted of 9 items including sex, grade, and academic performance. The academic performance and economic status were restructured into "upper, middle, lower". Subjective health perception and subjective oral health perception were reorganized as "health", "normal", "no health". The sub-areas of oral health behavior include five times of daily brushing during the day yesterday. The number of brushing times was "0", "1-2", "3", "more than 4" After lunch at school, brushing was restructured as "always," "sometimes," "not." The oral health status subscale consisted of 6 items including tooth breakage and toothache at the time of eating. Result : Tooth fracture(43.7 %), pain in mastication(43.7 %), tooth tingling(47.4 %), gum pain and bleeding(45 %), pain in buccal mucosa(43.8 %) and halitosis(46.6 %) were rare in adolescent having healthy oral health status cognitively(P<.001). Nosymptom adolescents without dental sealant showed low tooth fracture(0.64 times), pain in mastication(0.67 times), tooth tingling(0.59 times), gum pain and bleeding(0.84 times), pain in buccal mucosa(0.76 times), and halitosis(0.90 times). Nosymptom adolescents without scaling showed low tooth fracture(0.88 times), pain in mastication(1.03 times), tooth tingling(0.82 times), gum pain and bleeding(0.64 times), pain in buccal mucosa(0.70 times) and halitosis(0.82 times). Conclusion : This study revealed that oral health status is correlated with oral health behavior. Development of educational media and program, and aggressive promotion required to establish oral health Korean adolescent.