• Korean Journal of Environmental Agriculture
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• v.12 no.2
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• pp.144-152
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• 1993

A bacterium which degrades efficiently synthetic detergents was isolated from the polluted waters, activated sludge of wastewater treatment plants or polluted soil. This bacterium showed considerably higher growth rate in the agar plate containing $2,000{\mu}g/ml$ of synthetic detergents than any other isolated strains, was identified as a Pseudomonas fluorescens or strains similar to it. The strain was named as a Pseudomonas fluorescens S1. Optimum pH and temperature for the growth of the Pseudomonas fluorescens S1 were pH 7.0 and $30^{\circ}C$, respectively. The strain was resistant to streptomycin and gentamycin, but sensitive to kanamycin. The strain was greatly resistant to zinc chloride, lead nitrate and copper sulfate, but unable to grow in the presence of relatively low concentrations of mercury chloride and silver nitrate. This strain utilized benzene, catechol, cyclohexane and xylene as a sole carbon source. The strain was well grown in the medium containing ABS 10,000${\mu}g$/ml. Degradation of ABS was 55% and 60% at 20${\mu}g$/ml and 100${\mu}g$/ml of ABS, respectively. Benzene ring was degraded 45% in 100${\mu}g$/ml of ABS. During the incubation of the strain in the medium containing ABS 100${\mu}g$/ml and COD 10,000${\mu}g$/ml for 4 days, degradation of ABS and COD were reduced to 40${\mu}g$/ml and 3,200${\mu}g$/ml, respectively. Total amino acid content of the Pseudomonas fluorescens S1 grown with 1,000${\mu}g$/ml of ABS was 115mg/g cell, whereas its content was decreased in the bacterium grown without synthetic detergent by 9.4%.

• Korean Journal of Environmental Agriculture
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• v.32 no.2
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• pp.117-122
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• 2013

BACKGROUND: The scab, which is caused by Venturia nashicola, gives serious damages to pear trees. 'Niitaka' accounts for 82% of areas in pear cultivation. However 'Niitaka' is a scab susceptible cultivar. So, most of Korean farmers who growing pear trees have suffered by economic losses with the scab. In this research, we evaluated the scab resistance among elite pear seedlings to clarify genetics about the scab resistance. And we analyzed photosynthetic features with these seedlings to develop suitable cultivar which is advantageous for producing quality fruits during the growth and development of plants. METHODS AND RESULTS: We measured the rates of scab incidence among seedlings in a field experiment condition and an in-vitro test. An in-vitro test has been done with field experiment-based results. We made plant materials by grafting branches of each seedlings with 'Kongbae' rootstocks. And they had been grown for one month. Then, scab conidia suspension is sprayed to seedlings and sustained for 40 days under the controlled environment. As the results, 6 seedlings displayed lower incidence rates than other seedlings and 'Niitaka'. We also measured instant photosynthetic rates of each seedlings to determine the correlation between photosynthetic rates and fruit characteristics. However, it seemed that there is no correlation between them. CONCLUSION(S): Among the seedlings, 6 seedlings displayed the higher resistance to scab than other seedlings and 'Niitaka'. This characteristics is considered to be come from the gene expression of European pear. And we found that photosynthetic rate in trees rarely does not influence the fruit characteristics. It is considered to be affected by cultivar's own characteristics.

• Journal of the Korean Society of Earth Science Education
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• v.10 no.2
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• pp.122-139
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• 2017

The purposes of this study are to develop the STEAM program grounded on curriculum and to investigate educational effects of the developed program on students' attitude of science and science self-efficacy by application to elementary informal science education environment. In order to develop this program, the literature reviews were conducted and then STEAM education program based on the theme 'light' is developed. The developed program was revised and complemented through preliminary applications and consulting with experts, and applied to 65 students. A single group pre-post paired t-test was conducted through the students' attitude of science and science self-efficacy test. The semi-structure interviews were used to gather focused and additional data. The results of this study were as follows: firstly, STEAM education program was developed with the theme 'light' for elementary students in order to increase their interest related to real life. Secondly, the results indicated that the program was statistically significant on the attitude of science for the group of third and fourth graders. However, the effects of science self-efficacy did not appear a significant result for the third and fourth graders. They expressed one possible reason. The theme of light was not familiar with them because the theme was scheduled to teach in the second semester of the fourth graders. Some of students in this group did have a chance to learn the theme. Thirdly, the program was very effective for the fifth and sixth graders on their attitude of science and science self-efficacy. In conclusion, STEAM education program developed with the theme of light is contributed to elementary students' attitude of science in the informal science education. Students' learning experiences of relevant concepts can influence on students' science self-efficacy. It could be very important factor to consider students' grade level and previous learning experiences when the educational programs develop.

• Journal of the Korean Society of Earth Science Education
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• v.10 no.3
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• pp.262-277
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• 2017

Digital textbooks enable learning that is appropriate to the characteristics and level of learners through various interactions. The purpose of this study was to develop an instruction model that can more effectively use digital textbooks in elementary science classes and to verify its effectiveness. The results were as follows. The instruction model for helping learners complete their learning by using digital textbooks needs to receive diagnostic assessment and feedback on entry behavior, to build a self-directed learning environment, and to interact with teachers, students, and digital textbooks as scaffolding. In this study, we developed an instruction model using digital textbooks reflecting these characteristic. The instructional model consists of preparation, practice and solidity step. In the preparation step, the learner performs a diagnostic evaluation using digital textbooks. Based on the results, feedback provided at each level can complement the entry behavior and maintain interest in learning activities. In the practice step, self-directed learning is implemented using diverse functions of digital textbooks and various types of data. In the solidity step, learners can internalize the learning contents by reviewing video clips which are provided by teachers, performing problem-solving activities, and accessing outcomes accumulated by learners in the community online. In order to verify the effectiveness of this model, we selected the "Weather and our Life" unit. This experiment was conducted using 101 students in the 5th grade in B Elementary School in Gwangju Metropolitan City. In the experimental group, 50 students learned using a smart device that embodies digital textbooks applied with the instruction model. In the comparative group, 51 students were taught using the paper textbooks. The results were as follows. First, there was a significant effect on the improvement of the learning achievement in the experimental group with low academic ability compared with the comparative group with low academic ability. Second, there was a significant effect on self-directed learning attitude in the experimental group. Third, in the experimental group, the number of interactions with the learner, teacher, and digital textbook was higher than the comparative group. In conclusion, the digital textbooks based on the instruction model in elementary science classes developed in this study helped to improve learners' learning achievement and self-directed learning attitudes.

• Horticultural Science & Technology
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• v.17 no.5
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• pp.572-577
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• 1999

Research was initiated to evaluate plant growth regulator effects on the vertical shoot growth of Korean lawngrass and to determine desirable growth regulator and its rate. The experiments were conducted twice at different sites in 1995. All the tested growth regulators inhibited the growth, but the inhibition period was variable among the product in Experiments I and II. During the first week after treatment, there was approximately 10 to 20% growth reduction in most of the treated plots. In the amidochlor-treated plots, growth suppression was effective for 3 to 4 weeks at low to medium rates ($0.60mL{\cdot}m^{-2}$). A Type II growth regulator, trinexapac-ethyl exceeding the medium rate of $0.08mL{\cdot}m^{-2}$ consistently tended to suppress vertical shoot growth for 8 weeks, being above 35% reduction in both experiments. In the plots applied with mefluidide, growth suppression appeared with foliar discoloration 3 or 4 days earlier than the other growth regulators and continued to work till the 8 weeks after treatment. Suppression intensity on vertical shoot growth increased with time after treatment up to a certain period of time, depending on growth regulators. Generally, the higher the application rate, the greater the suppression intensity. Seasonal variation of activity and effectiveness of growth regulators was observed, resulting in lower suppression intensity in July than in June. It is expected to reduce mowing requirements by 30 to up to 60% for a certain period with a specific growth regulator. In low to medium maintenance of Korean lawngrass turf, a long-term suppression may be more effectively accomplished with trinexapac-ethyl rather than mefluidide and amidochlor in terms of vertical shoot growth inhibition. Therefore, turf managers will need to select proper growth regulator and determine optimum rate of application for turfgrass management, based on a defined period of mowing reduction.

• Journal of the Korea Organic Resources Recycling Association
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• v.28 no.3
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• pp.27-36
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• 2020

This study investigates the changes in inorganic composition and the microbial counts during the process of fermentation of mixed domestic organic resources for the development of alternatives for imported oil cake, and examines the characteristics of mixed fermentation organic fertilizer (MFOF). The effect of the MFOF on the lettuce growth is investigated in order to evaluate the possibility of replacing the existing mixed oil cake with the MFOF. Six kinds of domestic by-product resources, which are rice bran, distiller's dried grains, sesame meal, fish meal, and spent mushroom substrate, are mixed by mixing ratio and the composition was analyzed during the fermentation process for 90 days under moisture content 30% and sealed condition. During the 90 days of fermentation, the pH change of the MFOF was little, and the moisture content was maintained at 34-35% until the 60^th day of fermentation, and then decreased to 30-31% on the 90^th day. Total nitrogen content remained unchanged during the fermentation period, but total carbon content showed a significant difference on the 21^st day of fermentation. It was confirmed that the content of fertilizer composition (nitrogen, phosphate, and potash) of the MFOF was 8.7% or more, which is suitable for the minimum amount standard of the main nutrients to be contained in the organic fertilizer. During the fermentation process of organic fertilizer, the density of bacteria and actinomycetes increased until 60 days and 30 days, respectively, and thereafter little changes were shown, and fungal population showed an increasing trend. As a result of lettuce cultivation test in the greenhouse by applying the MFOF, the growth and yield were comparable to that of using the existing mixed oil cake fertilizer when 100% was applied based on crop standard nitrogen fertilizer level. The use of mixed fermentation organic fertilizer made with domestic by-product resources can be used for use in farms in the future and is expected to contribute to the stable production of environment friendly agricultural products.

• Cartoon and Animation Studies
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• s.51
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• pp.181-201
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• 2018

The cartoon industry in Korea has continued to decline due to the contraction of published comics market and decrease in the number of comic books rental stores until the 2000s when it rapidly started to experience qualitative changes and quantitative growth due to the emergence of webtoon. The market size of webtoon industry, valued at 420 billion won in 2015, is expected to grow to 880.5 billion won by 2018. Notably, most cartoonists who draw cartoon strips are using digital devices and producing scripts in data, thereby overcoming the geographical, spatial and physical limitation of contents. As a result, a favorable environment for the creation of local ecosystems is generated. While the infrastructures of human resources are steadily growing by region, cartoon industries that are supported by the government policy have shown good performance combined with factors of creative infrastructures in local areas such as webtoon experience centers, webtoon campuses and webtoon creation centers, etc. Nevertheless, it is true that cartoon infrastructures are substantially based on a capital area which leads to an imbalanced structure of cartoon industry. To see the statistics, companies of offline cartoon business in Seoul and Gyeonggi Province make up 87%, except for distribution industry. In addition, companies of online cartoon business which are situated outside of Seoul and Gyeonggi Province form merely 7.5%. Studies and research on local webtoon are inadequate. The existing studies on local webtoon usually focus on its industrial and economic values, mentioning the word "local" only sometimes. Therefore, this study looked into the current status of local webtoon of the present time for the current state of local cartoon ecosystem, middle and long-term support from the government, and an alternative in the future. Main challenges include the expansion of opportunities to enjoy cartoon cultures, the independence of cartoon infrastructure, and the settlement of regionally specialized cartoon cultures. It means that, in order to enable the cartoon ecosystem to settle down in local areas, it is vital to utilize and link basic infrastructures. Furthermore, it is necessary to consider independence and autonomy beyond the limited support by the government. Finally, webtoon should be designated as a culture, which can be a new direction of the development of local webtoon. Furthermore, desirable models should be continuously researched and studied, which are suitable for each region and connect them with regional tourism, culture and art industry. It will allow the webtoon industry to soft land in the industry. Local webtoon, which is a growth engine of regions and main contents of the fourth industrial revolution, is expected to be a momentum for the decentralization of power and reindustrialization of regions.

• Microbiology and Biotechnology Letters
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• v.40 no.2
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• pp.128-134
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• 2012

Foot and mouth disease (FMD) is one of the most notorious and contagious viral diseases afflicting cloven-hoofed animals. In this study, the physicochemical properties of leachate from a FMD landfill site at 773-1, Waryong, Andong, Korea and the ground water from 777, Waryong, Andong, Korea, were analyzed for 1 year from December $10^{th}$ 2010 to November $17^{th}$ 2011. The leachate was collected from the FMD landfill site during March, May, July, September and November, 2011 and changes in pH, brix, water content, insoluble solids, crude proteins, crude lipids, total and reducing sugars and ash content were determined. Considering the annual profiles of temperature and rainfall at the FMD landfill site, the dramatic changes in the physicochemical properties of the leachate from March to July, and especially from May to July, such as increases in pH, and a rapid reduction of brix and organic matter, may be closely linked to the growth of microorganisms in the leachate. The sharp decreases in the concentration of biominerals, such as Mg, Ca, and Fe from 1073, 4311 and 56.2 ppm in March to 151, 78, and 0.1 ppm in November, further suggest that decreases in organic matter in the leachate result from degradation by microorganisms originating from the intestines of the livestock. Analysis of the profiles of the organic materials in the leachate revealed that the properties of the leachate were similar to those of excremental matter-derived water. These results could be applied to a number of fields for the analysis of organic matter behavior, the development of the degradation process, and risk analysis in the environment for hygiene and food industries, of leachate from FMD landfill sites.

• Journal of Pharmaceutical Investigation
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• v.35 no.3
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• pp.201-205
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• 2005

The aim of publishing the Korean Pharmaceutical Codex is to update and set specification of essential drugs for humane health. In accordance with speedy development of new drugs and improvement of science and technology, the need of revision of drug specification through the ICH guidelines and discussions between regulatory agency and pharmaceutical industry for the quality assurance of safer and efficient drugs is getting higher. The first edition of Korean Pharmaceutical Codex was published in 1983. Now, the third revision of the Codex is prepared because of the revision of domestic and foreign Pharmacopeias, changes of drug control environment, improvement of science and technology and so on. The aim of 3th edition is to improve the quality of essential drugs through the setting of the required specifications and discussions between the regulatory agency and pharmaceutical industry.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.10 no.1
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• pp.63-75
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• 2012

This paper gives some basic requirements and preferences of various geological environmental conditions for the final deep geological repository of spent nuclear fuel (SNF). This study also indicates how the requirements and preferences are to be considered prior to the selection of sites for a site investigation as well as the final disposal in Korea. The results of the study are based on the knowledge and experience from the IAEA and NEA/OECD as well as the advanced countries in SNF disposal project. This study discusses and suggests preliminary guideline of the disposal requirements including geological, mechanical, thermal, hydrogeological, chemical and transport properties of host rock with long term geological stabilities which influence the functions of a multi-barrier disposal system. To apply and determine whether requirements and preferences for a given parameter are satisfied at different stages during a site selection and suitability assessment of a final disposal site, the quantitative criteria in each area should be formulated with credibility through relevant research and development efforts for the deep geological environment during the site screening and selection processes as well as specific studies such as productions of safety cases and validation studies using a generic underground research laboratory (URL) in Korea.