• Korean Journal of Microbiology
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• v.54 no.4
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• pp.369-378
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• 2018

This study was conducted to evaluate effects of dietary microbial probiotics on the growth and disease resistance of olive flounder (Paralichthys olivaceus) in a recirculating aquaculture system (RAS), and the effects of the probiotic bioaugmentation on the microbial community structure and water quality. For the analysis, 80 juvenile fish (average weight, $25.7{\pm}7.6g$; average length, $15.2{\pm}1.7cm$) were fed a basal diet containing a commercial microbial product CES-AQ1 (CES; $1{\times}10^9\;CFU/kg$ diet) in an RAS for 8 weeks. Weight gain, the specific growth rate, feed efficiency, and protein efficiency ratio of the fish fed the CES diet in the RAS were 1.5~2.5 times higher than those of fish fed the basal diet alone, or the basal diet containing oxytetracycline (OTC), yeast plus bacterium, or Bacillus subtilis in a still water system. There was no significant difference in the pathogen challenge test between fish fed the OTC diet and fish fed the CES diet in the RAS, suggesting the CES-AQ1 probiotic used in the RAS as a potential replacement for antibiotics. The RAS biofilter maintained the highest microbial diversity and appeared to harbor microbial communities with ammonium oxidation, denitrification, and fish pathogen suppression functions. Ammonia, which is hazardous to fish, was significantly decreased to < 0.5 mg/L in 19 days, indicating the effectiveness of probiotic supplementation to maintain good water quality in RAS. These results suggest that the intestinal microbial communities of fish are stabilized by a probiotic-containing diet (CES) and that bioaugmentation with probiotics may be an eco-friendly and economical supplement for aquaculture of olive flounder, promoting both good water quality and fish health in an RAS.

• Korean Journal of Heritage: History & Science
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• v.54 no.3
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• pp.150-167
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• 2021

Since the advent of tertiary curriculum, middle school history education has been focused on political history, but many students perceive history as a simple memorization subject and complain about difficulties in abstract learning. The researcher saw this problem as caused by the history curriculum, and carried out this study for the purpose of proposing a revitalization of cultural property education in the middle school history curriculum. First, through the analysis of prior research, the usefulness of cultural property education, such as nurturing creative talent and realizing interactive history classes, was revealed, and the problems of the current political history-centered middle school history curriculum were pointed out. Afterwards, as a result of conducting an opinion survey on middle school 3rd grade students and social studies teachers, it was found that first, both middle school students and their teachers thought that the current political history-centered history had much room for improvement. Second, all groups agreed on the necessity of cultural property education in history education. However, in reality, it was found that it was not easy to sufficiently educate students about cultural property in a political history-centered curriculum. Third, teachers thought that it was necessary to improve the current history curriculum in order to enhance cultural property education. Based on these findings, the researcher suggested an improvement plan for the 2015 revised history curriculum. First, in the 'nature of the subject' section, cultural properties and historical materials should be included, and in the 'objective' section, politics, economy, society, and culture should be included. Contents related to cultural properties should be added to the sub-themes in the 'content system and achievement standards', and cultural properties-related contents should be further reinforced in the achievement standards, 'teaching, learning and evaluation'. It was suggested that this section should include cultural property learning and historical material learning, and guidance on teaching and learning methods of cultural property education should be added. If these aspects are reflected in the 2022 revised curriculum that is currently being developed, cultural property education will be improved, and more lively history education will be provided to students.

• Journal of the Korea Organic Resources Recycling Association
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• v.28 no.4
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• pp.77-85
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• 2020

This study analyzes the effects of mixed fermented organic fertilizer on chinese cabbage growth and soil properties in order to investigate the nutritional effects of organic fertilizers, which are developed as an alternative fertilizer for imported castor oil cake. In this study, four treatments were set up: 100% and 200% rate of nitrogen application (320 kg ha-1 for Chinese cabbage) on mixed fermented organic fertilizer A(FA) and mixed fermented organic fertilizer B(FB), respectively, 100% rates of the mixed expeller cake (MEC) fertilizer, and the untreated control. Results revealed that the growth and yield of Chinese cabbage increased as more fermented organic fertilizer was used. However, while there were no significant differences in growth characteristics between treatments of 100% rate of mixed fermented organic fertilizer and 100% rate of MEC, the impacts on yields resulted similar. The nitrogen use efficiency (NUE) of Chinese cabbage was measured a range of 20-31% depending on the response to treatment. The 100% FA showed the same as NUE and nitrogen absorption with 100% rate of MEC. Regarding soil properties after cultivation, there were no significant differences among the effects of fertilizers in pH, EC, soil organic matter, and available phosphate. However, the content of exchangeable cations(K, Ca, Mg) was higher in areas treated with mixed fermented organic fertilizer than in untreated areas. Furthermore, the bacterial population density in the soil was higher in areas treated with mixed fermented organic fertilizer than in untreated areas and increased as more mixed fermented organic fertilizer was used. There were no significant differences in the population density of actinomycetes and fungi when fertilizer was applied to the soil. These results also show that FA, as a alternative organic fertilizer for imported castor oil cake, has similar nutritional effects as that of MEC. Therefore, further research the appropriate amounts of fertilizer is required to achieve economical and eco-friendly nutrient management.

• Ecology and Resilient Infrastructure
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• v.7 no.4
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• pp.388-395
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• 2020

Exotic species have been imported for economic purposes, but more recently, an increasing number of animals are imported as pets. With the increasing popularity of two species of turtles, Mauremys sinensis and Pseudemys concinna, the number of pet turtle owners has gradually increased since 2014. The number of turtles increased by 180 in 2017 and 281 in 2019. However, these turtle species have been abandoned to nature, owing to their long lifespans and the changes in conditions of pet owners. The two turtle species have been designated as invasive alien species (AIS) in Korea considering their ecological risks, and the Biological Diversity Act prohibits their release. The owners of Mauremys sinensis and Pseudemys concinna are required to submit the "Application for Approval of Breeding and Grace for AIS" document. In this study, the breeding conditions for the two turtle species were investigated by analyzing the information in the submitted applications for six months (e.g., the suitability of breeding facilities, number of turtles, breeding period, type of pet adoption, and local district of pet owner). A total of 614 cases were analyzed. Because only 58% of breeders provided suitable breeding conditions, breeding information and responsible pet ownership training should be offered to prevent abandonment in natural ecosystems. In addition, continuous monitoring is necessary to prepare for potential problems caused by the lack of information in many applications and the one-off licensing policy.

• The Journal of Sustainable Design and Educational Environment Research
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• v.20 no.2
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• pp.1-10
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• 2021

The results of research and analysis are as follows: First, there were 108 types of change patterns in the number of elementary school students. Second, based on the similarity of 108 types of change patterns in the number of students, a type system diagram was presented. Third, in the case of a total of 18 types of change patterns in the number of students, the number of students decreased significantly due to the establishment of additional schools on top of the existing schools. The result of a a long-term survey and analysis on the trend of increase and decrease in the number of students across the country shows an urgent need todevelop policy tasks across the entire school accommodation plan, such as the establishment of differentiated schools suitable for regional characteristics, relocation, consolidation, reorganization of school districts, remodeling, and appropriatization projects.

• Journal of The Korean Society of Grassland and Forage Science
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• v.40 no.4
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• pp.221-226
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• 2020

This experiment was conducted to compare the seed productivity of the Italian ryegrass(Lolium multiflorum Lam.) varieties sown in the spring in Gangwon region. The experiment was randomized block design with three replications. The Experimental field was located in alpine areas of about 600 m above sea level in Gangwon province. The tested Italian Ryegrass varieties were 'Greenfarm', 'Greencall' and 'Kowinearly' developed by National Institute of Animal Science, RDA. Italian Ryegrass varieties were sown on March 26, 2020, and the harvest was on the 60th day of mean heading date, July 2. The heading date of Kowinearly was May 8, but Greenfarm and Greencall was May 4. The plant length was the largest in the Kowinearly variety. However, the Kowinearly suffered severe lodging. There was no significant difference in the length of spike among varieties, and the number of seeds per spike was the lowest in Greenfarm at 118.5 seed/spike. As for the seed weight per spike, the Greenfarm variety was significantly lower at 0.56 g/spike, but the 1,000 seed weight was the heaviest in the Greenfarm at 2.5g.. The number of spike per unit area was the highest in Greenfarm at 906/㎡. The dry matter content of seeds was the highest in Greenfarm at 54.3%, and for straw, Kowinearly was the highest at 35.3%. Seed productivity was not significant among varieties, and the average was 1,493 kg/ha. The yield of straw after seed production was also not significant among varieties (P>0.05), and the average was 3,172 kg/ha. From the above results, the production of Italian ryegrass seeds through spring sowing in the Gangwon region is not much than autumn seeding, requiring the input of various technologies to increase productivity in the future, and it is desirable to determine the production cost through economic analysis was judged.

• Korean Chemical Engineering Research
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• v.60 no.2
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• pp.243-248
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• 2022

As the scope of use of portable and wearable electronic devices is expanding, the limitations of heavy and bulky solid-state batteries are being revealed. Given that, it is urgent to develop a small energy harvesting device that can partially share the role of a battery and the utilization of energy sources that are thrown away in daily life is becoming more important. Contact electrification, which generates electricity based on the coupling of the triboelectric effect and electrical induction when the two material surfaces are in contact and separated, can effectively harvest the physical and mechanical energy sources existing in the surrounding environment without going through a complicated intermediate process. Recently, the interest in the harvest and utilization of wind energy is growing since the wind is an infinitely ecofriendly energy source among the various environmental energy sources that exist in human surroundings. In this study, the optimization of the energy harvesting device for the effective harvest of wind energy based on the contact electrification was analyzed and then, the utilization strategy to maximize the utilization of the generated electricity was investigated. Natural wind based Fluttering TENG (NF-TENG) using fluttering film was developed, and design optimization was conducted. Moreover, the safe high voltage generation system was developed and a plan for application in the field requiring high voltage was proposed by highlighting the unique characteristics of TENG that generates low current and high voltage. In this respect, the result of this study demonstrates that a portable energy harvesting device based on the contact electrification shows great potential as a strategy to harvest wind energy thrown away in daily life and use it widely in fields requiring high voltage.

• The Korean Journal of Nuclear Medicine Technology
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• v.26 no.1
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• pp.42-46
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• 2022

Purpose In the meantime, there have been not many samples that require dilution, and it has been difficult for the examiner to set an appropriate dilution multiple for RIA test item and report the results. Accordingly, it was judged that it was necessary to set the maximum dilution multiple for each test and to verify the upper limit of the clinical reportable range. Therefore, in this study, the maximum dilution multiple for each RIA test was set and the upper limit of the clinical reportable range was verified accordingly Materials and Methods Among all RIA tests conducted at Asan Medical Center, the study treated on 30 types of tests which also conduct the dilution test. Data from March to July 2021 were collected and analyzed. The study was conducted on samples subjected to serial dilutions such as X2, X4 or X10, X10², X10³, X10⁴, X10⁵. Results Among a total of 30 test types, 18 test types have more than 5 N values in the tolerance range of 80~120%. As a result of the verification of maximum dilution multiples, the test set to 10⁴ is 𝛼-fetoprotein and thyroglobulin, and the test set to 10³ is CA-125, CEA, and 𝛽-hCG, and the test set to 10² is Free PSA, PSA, CA15-3, SCC, Ferritin, PTH, Cortisol, and Calcitonin. Tests set to 10 include three categories: 𝛽2-Microglobulin, C-peptide, and Testosterone. Conclusion It is expected that it will contribute to improving the quality of nuclear medicine blood tests as the results of dilution experiments can be reported quickly and accurately through the verification of the clinical reportable range.

• Journal of Korean Society of Forest Science
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• v.111 no.3
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• pp.365-373
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• 2022

We compared carbon stocks in tree biomass and soils of Quercus acutissima, Q. mongolica, Q. serrata, and Q. variabilis stands. A total of 531 plots (Q. acutissima: 110 plots, Q. mongolica: 177 plots, Q. serrata: 96 plots, Q. variabilis: 148 plots) were examined between 2016 and 2021 to determine the tree biomass and soil carbon stocks throughout the country. The carbon stocks of tree biomass were significantly higher in Q. mongolica (mean stand age, 57 years, 144.9 Mg C ha^-1) than in Q. variabilis (mean stand age, 43 years, 123.7 Mg C ha^-1), Q. serrata (mean stand age, 43 years, 120.1 Mg C ha^-1), and Q. acutissima (mean stand age, 36 years, 113.2 Mg C ha^-1) stands. The soil carbon concentration was significantly higher in Q. mongolica (A: 43.1 mg C g-1) than in Q. serrata (31.0 mg C g-1), Q. variabilis (25.31 mg C g-1), and Q. acutissima (24.4 mg C g-1) stands. The soil carbon stocks were significantly higher in Q. mongolica (116.8 Mg C ha^-1) than in Q. acutissima (49.3 Mg C ha^-1) stands. Total carbon stocks of tree biomass and soil were highest in Q. mongolica (262 Mg C ha^-1), followed by Q. serrata (218 Mg C ha^-1), Q. variabilis (211 Mg C ha^-1), and Q. acutissima (163 Mg C ha^-1) stands. Multiple linear regressions were performed to estimate the total carbon stocks of the four Quercus spp., and results showed that total carbon stocks increased with increasing elevation, mean diameter at breast height, and basal areas. Basal area and elevation of Quercus spp. stands were important explanatory variables based on multiple linear regressions for estimating carbon stocks.

• The Journal of the Convergence on Culture Technology
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• v.8 no.3
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• pp.581-587
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• 2022

The water god, Venerable Bhadra, Indian Tammola (Tamla as the 'mol' and 'ju' characters were eliminated) came to Tamla with 900 Arahants(The highest Buddhist monks) around 563-483 BC. It is the propagation of Buddhism through the world's most sacred water (Heiligkeit). The traces of the three surnames of Goyangbu are the first samsunghyeol and the dwelling of the den of Jonjaam(cave of venerable Bhadra) in Yeongsil, giving a glimpse into the era of living in caves. The second is a link that is in line with 3, the basic number in the decomposition of 900 (=3^*3^*100) disciples of Bhadra, considering that 3 and 3 of the three surnames in Goyangbu are three times 9. At this time, 3 is the person of heaven and earth, religiously, marriage, hope, or complete number, and Jeju culture is resting everywhere. For example, 3 of the samsunghyeol, 3 of the 1, 2, 3 Dodong, 3 of the 3 Dado, 3 of the 3 Mudo, 3 of the 3 disasters, 3 of the Goyangbu 3-surnames, 3 of the house Olle Jeongnang and, among 900 (=3^*3^*100) disciples of Venerable Bhadra, the common factor is 3. It is the 'island of 3'. These papers consist of 1 and 2 parts. In Part 1, the name of Tamla came from Tammola, India, and 900 Indian Buddhist Arahants estimated that the three surnames in Goyangbu were the ancestors. Part 2 highlights how the basic principle of jeonganag derived from Indian customs has evolved and is being used in modern mobile communication and DNA gene life science.