• Journal of Environmental Science International
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• v.28 no.12
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• pp.1061-1069
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• 2019

Common reed (Phragmites australis) is widespread in reclaimed land and wetland habitats. Every year, the common reed produces extensive colonies by means of underground rhizomes and ground-surface stolons. From an agricultural point of view, the common reed's large biomass is a good material for supplying organic matter. However, it has not yet been studied in terms of seedling production, transplanting conditions, and decomposition characteristics in reclaimed land. Seeds were harvested from the native common reed in Saemangeum, South Korea, the previous year and stored on an open field. The seeds were sowed in the greenhouse at the beginning of April. Common reed decomposition was studied from June to September, with the use of coarse mesh (5 mm) stem litterbags, on three samping dates and with five replicate packs per sample. These packs were dug in five soil condition (low-salinity topsoil, subsoil, high-salinity topsoil, subsoil, paddy topsoil) to 0.2 m and 0.4 m depth. The highest germination rate of common reed seeds was observed in non-salt solution, but the exhibited germination rate was 70% at 9.38 dS m^-1. The plant height of young reed decreased steadily with increasing salinity, but leaf number did not decrease by 9.38 dS m^-1. The survival rate of the two-year-old reed was 83.3%, which was 35% higher than that of the one-year reed. The transplant success rate was 0% in the no vinyl mulching in the soil, but the first year and second year seedlings survived rates were 63% and 83.3%, respectively, in vinyl mulching. Common reed decomposition rates were faster low salinity than high salinity. All nutrient contents were found to fluctuate significantly with time by soil conditions. We also need to study the growth rate of reed transplanting seedlings by soil moisture contents and the comparison of degradation in common reed tissues.

• The Pure and Applied Mathematics
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• v.23 no.2
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• pp.131-143
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• 2016

In this paper, we present some common fixed point theorems for two pairs of weakly compatible self-mappings on multiplicative metric spaces satisfying a generalized Meir-Keeler type contractive condition. The results obtained in this paper extend, improve and generalize some well known comparable results in literature.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.29 no.12
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• pp.963-968
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• 2018

In this paper, a compact common mode filter using passive elements is designed and fabricated. To design a common mode filter with required frequency response, the equivalent circuits of the common mode filter in differential mode and common mode were analyzed. Compared with the former filter using a ${\lambda}/4$ resonator, the size of the proposed structure was reduced by 60 %. The fabricated common mode filter has a maximum differential mode insertion loss of 1.2 dB and a minimum common mode absorption efficiency of 78.2% in the CMA - bandwidth of 27.5 %.

• Journal of The Korean Association For Science Education
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• v.13 no.3
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• pp.389-395
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• 1993

Science textbooks which were compiled by CHOSUN Government General are known as books which appeared after 'Science Textbook for Common School' (1923-) compiled by CHOSUN Government General which are almost similar to state authorized textbooks and are also known as leaving the effect on 'Science Textbook for Elementary School' (1931-) which were focused on the subjects being issued since then and 'Science Text for Elementary Course' (1942-) being compiled by the Education Ministry, However in this research it was found out that there were publications in 1911, 1913 and 1921 and they were harbingers for 'Science Textbook for Elementary School' 0931-). For this reason it was decided to report overall picture on the science textbooks being compiled by CHOSUN Government General. And it was possible to illustrate that such textbooks can be classified into following 5 periods ; The 1st period:The time for search--'Science Textbook for Students of Common school' 1911 compiled by CHOSUN Government General. The 2nd period:Commencing separate compilation--'Science Textbook for Common School' 1913 compiled by CHOSUN Government General. (The 2'nd period:Final Separate Compilation-- Reissue after corrections of 'Science Textbook for Common School' compiled by CHOSUN Government General, 1921.) The 3rd period:Same as the state authorized science textbook of Japan--' Science Textbook for Common School' compiled by CHOSUN Government General, totally 3 books 1923-. The 4th period:Separate compilation, centered on subjects--'Science Textbook for Elementary School' compiled by CHOSUN Government General, 1931-. (The 4'th period:Changers of subjects--'Science Text for Elementary School' compiled by CHOSUN Government General, 1937-. The 5th period:Matched to compiled by the Education Ministry--'Observation of Nature' compiled by CHOSUN Government General, 1942-'Science Text for Elementary School'(Writing laterally) 1943-.

• Journal of electromagnetic engineering and science
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• v.15 no.2
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• pp.89-96
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• 2015

This paper describes the application of a passive noise cancellation method to a prototype inductor-inductor-capacitor (LLC) resonant converter by placing a compensation winding in a transformer to reduce common mode noise. The connection method for the compensation winding is investigated. A circuit analysis is implemented for the displacement currents between the primary and secondary windings in the transformer. The analyzed displacement currents are verified by performing a circuit simulation and a proper compensation winding connection that reduces common mode noise is found. The measurement results show that common mode noise is reduced effectively up to 20 dB in the 1 to 7 MHz frequency region for the prototype LLC resonant converter by using the proposed passive noise cancellation method.

• Asian-Australasian Journal of Animal Sciences
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• v.10 no.2
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• pp.206-209
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• 1997

The effect of supplementation of Jackfruit (Artocarpus heterrophyllus) tree leaves and mashkalai (Vigna mungo) barn on the intake and digestibility of freshly cut common grass by Black Bengal goats was evaluated. Twelve castrated goats of approximately 5-6 months age were randomly allocated to three dietary treatments: freshly cut common grass ad libitum, common grass+100g Jackfruit tree leaves and common grass+100g mashkalai bran. Although digestibilities of dry matter, organic matter, nitrogen and neutral detergent fibre were very similar in the grass alone and mashkalai bran supplemented goats but the values were significantly (P < 0.01) higher than those observed in the Jackfruit leaves supplemented goats. Supplementation of mashkalai bran promoted higher (p < 0.05) digestible nutrients intake with the consequent higher daily live weight gain (75 g) than those fed grass alone (31 g). It could be concluded that mashkalai bran could be a suitable supplement for goats consuming common grass in the tropics and subtropics.

• Korean Management Science Review
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• v.19 no.1
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• pp.1-12
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• 2002

Performances of common zone with various sizes are examined for possible demand rate variations for an AS/RS. Common zone is a middle area located between the 1st class and the 2nd class to be used by the 1st class Items if the assigned racks are not enough. This area is designed to resolve the rack shortage problem associated with a particular class. In the previous researches, effect of demand rate variation is Ignored since flxed demand rate is assumed. It is found that rack shortage rate is decreased up to 67% of common zone size. However, no difference is found at above 70%. Waiting time tends to be longer with Increased common zone while travel time and throughput are not affected at all with the common zone sloe.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.49 no.6
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• pp.862-866
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• 2016

Common stalked barnacle Pollicipes mitella is a filter-feeding crustacean that attaches itself to the surfaces of rocks in the ocean intertidal zone. Pollicipes mitella is one of about a dozen species of goose barnacle that are gathered commercially for human consumption. In Portugal and Spain, they are a widely consumed and expensive delicacy known as "Percebes (Pollicipes pollicipes )". However, common stalked barnacle is less popular in Korea, and information on its nutritional component is not yet available. In the present study, we analyzed the proximate and fatty acid compositions and mineral content of common stalked barnacle (muscle and cirrus). The muscle and cirrus of common stalked barnacle were 15.1% and 14.3% protein, and 3.31% and 1.81% lipid, respectively. The prominent fatty acids in the muscle and cirrus were 22:6n-3 (docosahexaenoic acid, DHA), 16:0, 20:5n-3 (eicosapentaenoic acid, EPA), 18:0, 18:1n-9, 16:1n-7 and 14:0. In particular, common stalked barnacle contained high levels of n-3 polyunsaturated fatty acids, such as DHA (25.4-25.6%) and EPA (14.7-15.1%), and low levels of the n-6 fatty acid, 20:4n-6 (1.2-1.3%). Common stalked barnacle contained a relatively large amount of Zn (10-42 mg/100 g) in its muscle and cirrus.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 2017.04a
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• pp.31-31
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• 2017

On farm evaluation for the control of airborne diseases like FMD and flu virus has been done in past but control of disease in process of transportation of livestock and manures is still needed. The objective of this study was to predict a common pattern of livestock vehicles movement. The analysis were done on GPS data, collected from drivers of livestock vehicles in Jeju Island, South Korea in year 2012 and 2013. The GPS data include the coordinates of moving vehicles according to time and dates, livestock farms and manure keeping sites. 2012 year data was added to ArcGIS and different tools were used for predicting common vehicle moving pattern. The common pattern of year 2012 were determined and considered as predicted common pattern for year 2013. To compare with actual pattern of year 2013 the same analysis was done to find the difference in 2012 and 2013 pattern. When the manure keeping sites and livestock farms were same in both years, as a result common pattern of 2012 and 2013 were similar but difference were found in patterns when the manure keeping sites and livestock farms were changed. In future for more accurate results and to predict the accurate pattern of vehicles movement, more dependent and independent variables will be required to make a suitable model for prediction.

• Journal of the Korean Society of Earth Science Education
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• v.12 no.3
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• pp.224-238
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• 2019

The purpose of this study is to analyze the perception of integrated school education and education for sustainable development of secondary school science teachers, judging that the existence of a common science teacher qualification certificate is related to the expertise of the common science map. To that end, the survey was conducted for three months from June to August 2018 for secondary school science teachers, and multiple choice questions were analyzed as statistical processing and descriptive questions as topical modeling. According to the analysis, teachers with a common science teacher qualification certificate had a high awareness of integrated school education, and the response average was high in all areas of value, direction and success condition of integrated school education. In addition, the average response of teachers with a common science teacher qualification certificate was also found to be higher than those with a common science teacher qualification. There were no major differences in perception between the two groups on the strength of science education and ESD integration, but the difference was that teachers with a common science teaching certificate focused on science in all topics and recognized science as a medium for each topic compared to teachers who did not.