• Korean Journal of Soil Science and Fertilizer
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• v.44 no.5
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• pp.937-943
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• 2011

In order to develop constructed wetlands for treating hydroponic wastewater in greenhouses, removal efficiencies and decomposition velocities of pollutants in constructed wetland were investigated for treating hydroponic wastewater. Removal rates of BOD, COD, SS, T-N and T-P in effluent in constructed wetlands were 88%, 79%, 92%, 64% and 92%, respectively. The decomposition velocities (K; $day^{-1}$) of pollutants in $1^{st}$ HF bed of constructed wetlands were higher in the order of SS ($0.54day^{-1}$) > BOD ($0.39day^{-1}$) > COD ($0.27day^{-1}$) > T-P ($0.26day^{-1}$) > T-N ($0.06day^{-1}$). In $1^{st}$ HF bed of constructed wetlands, the decomposition velocity of SS was rapid than that for BOD, COD, T-N and T-P in constructed wetland for treating hydroponic wastewater. The decomposition velocity (K; $day^{-1}$) of pollutants in $2^{nd}$ HF bed of constructed wetland were higher in the order of T-P ($0.52day^{-1}$) > BOD ($0.28day^{-1}$) > COD ($0.15day^{-1}$) > T-N ($0.06day^{-1}$) > SS ($0.10day^{-1}$). In $2^{nd}$ HF bed of constructed wetlands, the decomposition velocity of T-P was rapid than that for BOD, COD, SS and T-N in constructed wetland for treating hydroponic wastewater.

• Korean Journal of Soil Science and Fertilizer
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• v.44 no.3
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• pp.434-441
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• 2011

To improve T-N and T-P removal efficiencies, removal efficiencies of pollutants in full-scale livestock wastewater treatment plant by natural purification method with water plant filtration and activated sludge beds were investigated under different re-injection rates and injection methods of livestock wastewater. The removal rates of COD, SS, T-N, and T-P in effluent in full-scale livestock wastewater treatment plant were in the order of 30% < 70% ${\leq}$ 100 % at different re-injection rates. The removal rates of pollutants in effluent in full-scale livestock wastewater treatment plant were higher as re-injection rate of livestock wastewater increased. Removal rates of COD, SS, T-N, and T-P by continuous injection were slightly higher than those by intermittent injection method in full-scale livestock wastewater treatment plant. Removal rates of COD, SS, T-N, and T-P by continuous injection method in full-scale livestock wastewater treatment plant with water plant filtration and activated sludge beds were 99.5, 99.8, 99.0 and 99.8%, respectively.

• Journal of Sericultural and Entomological Science
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• v.53 no.2
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• pp.135-142
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• 2015

The American cockroaches, Periplaneta americana L. was the most important worldwide pest species. It has been an public health problems. We were determinated life cycle and extraction of crude extracts by chemical reagents from cockraches (P. americana L.). The extracted crude solution has been antibacterial activity to gram negative bacteria (Pseudomonas aeruginosa, $6.44{\pm}1.03mm$), gram positive bacteria (Bacillus subtilis, $1.88{\pm}0.40mm$), and fungus (Candida albicans, $5.61{\pm}0.57mm$) using radial diffusion assay. We were analysed of up-regulation of Glutathione-S-transferases (GSTs) stimulation, indicating that antioxidantial protein from various classes are simultaneously expressed in a single insect upon infection or injury. The gene from Periplaneta americana L. were cloned, analysed sequence, and measured protein expression by Real Time PCR (Polymerase Chain Reaction).

• Korean Journal of Psychosomatic Medicine
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• v.23 no.2
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• pp.86-92
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• 2015

Objectives : The aim of this study was to investigate the gender differences of direct aggression and relational aggression in Korean elementary and middle school students. Methods : Parents of 946 elementary school students(age $9.54{\pm}1.72$ years, 485 boys, 461 girls) completed the Child Behavior Checklist(CBCL). Six-hundred-and-three middle school students(age $13.98{\pm}0.93$ years, 301 boys, 302 girls) completed the Youth Self-Report(YSR). Independent t-test, chi-square test, and Fisher's exact test were used. Results : Boys had significantly higher direct aggression scores than girls in elementary school students(p<0.001). There was no significance gender difference of relational aggression in elementary school students(p=0.235). In middle school students, boys had significantly higher direct aggression than girls(p=0.017), and girls had significantly higher relational aggression compared to the boys(p<0.001). Conclusions : Our results suggest the presence of gender differences in manifestation of aggression subtypes in Korean elementary and middle school students. These gender differences should be taken into account in prevention and intervention approaches of aggression in children and adolescents.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.16 no.4
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• pp.195-209
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• 2021

According to the 2019-2020 social media usage survey conducted by the Seoul e-commerce center, 5 out of 10 consumers have experienced shopping through social media. The cost of traditional advertising media has been reduced and advertising spending on social media has risen by 74%, indicating that social media is becoming a more important marketing element. While the number of users of social media has increased and corporate marketing activities have increased accordingly, research has been conducted in various aspects of marketing such as user motivation for social media, satisfaction, and purchase intention. There was no subdivided study on the differences in the social media usage frequency of consumers in actual purchasing behavior. This study attempted to identify differences in consumer characteristics by cluster in the agrifood purchase situation by grouping them by type according to the frequency of use of social media for consumers who purchase agri-food online. Product involvement, product need, and online purchase channel Consumer characteristics such as demographic distribution, perceived risk, and eating and lifestyle in each cluster were checked for the three agrifood purchase situations including choice, and types for each cluster were presented. To this end, questionnaire data on the frequency of social media use and online agrifood purchase behavior were collected from 245 consumers, and the validity of the measurement variables was secured through factor analysis and reliability analysis. As a result of cluster analysis according to the frequency of social media use, it was divided into three clusters. The first cluster was a group that mainly used open social media, and the second cluster was a group that used both open and closed social media and online shopping malls; The third cluster was a group with low online media usage overall, and the characteristics of each cluster appeared. Through regression analysis, the effect on product involvement, product need, and purchase channel selection when purchasing agri-food online through each of the three clusters was confirmed through regression analysis. As a result of the regression analysis, the characteristic of cluster 1 in the situation of purchasing agri-food online is a male in his 30s living in a rural area who has no reluctance to purchase agri-food on social media or online shopping malls. The characteristics of cluster 2 are mainly consumers who are interested in purchasing health food, and the consumer characteristics are represented. In the case of cluster 3, when purchasing products online, they purchase after considering quality and price a lot, and the consumer characteristics are represented as people who are more confident in purchasing offline than online. Through this study, it is judged that by identifying the differences in consumer characteristics that appear in the agri-food purchase situation according to the frequency of social media use, it can be helpful in strategic judgments in marketing practice on social media customer targeting and customer segmentation.

• Journal of Wetlands Research
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• v.23 no.4
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• pp.327-341
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• 2021

The riparian eco-belt is an efficient technique that can reduce non-point pollution sources in the basin and improve ecological connectivity and health. In Korea, a legal system for the construction and management of riparian eco-belts is in operation. However, it is currently excluded that rivers and floodplains in dam reservoir that are advantageous for buffer functions such as control of non-point pollutants and ecological habitats. Accordingly, this study presented and analyzed a plan to select a site for an integrated riparian ecol-belt that comprehensively evaluates the water quality and ecosystem characteristics of each dam floodplain and riparian zone for the Daecheong Dam basin in Geum River watershed. First, the Daecheong Dam basin was divided into 138 sub-basin with GIS, and the riparian zone adjacent to the dam floodplain was analyzed. Sixteen evaluation factors related to the ecosystem and water quality impact that affect the selection of integrated riparian eco-belt were decided, and weights for the importance of each factor were set through AHP analysis. The priority of site suitability was derived by conducting an integrated evaluation by applying weights to sub-basin by floodplains and riparian zone factors. In order to determine whether the sites derived through GIS site analysis are sutiable for actual implementation, five sites were inspected according to three factors: land use, pollution sources, and ecological connectivity. As a result, it was confirmed that all sites were appropriate to apply integrated riparian ecol-belt. It is judged that the riparian eco-belt site analysis technique proposed through this study can be applied as a useful tool when establishing an integrated riparian zone management policy in the future. However, it might be necessary to experiment various evaluation factors and weights for each item according to the characteristics and issues of each dam. Additional research need to be conducted on elaborated conservation and restoration strategies considering the Green-Blue Network aspect, evaluation of ecosystem services, and interconnection between related laws and policy and its improvements.

• Journal of Plant Biotechnology
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• v.48 no.3
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• pp.179-185
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• 2021

Indoor gardening includes wall greening, terrariums, and flower arrangements. Among these types of indoor gardens, the terrarium is easy to access for the general public, but in Korea, because of the focus on esthetics, the original purpose of creating terrariums, which was to grow plants sustainably in an enclosed space, has been lost. In addition, miniaturization of plants is required to grow plants in an enclosed space. Since the available plant species suitable for a terrarium are limited, only plants such as succulents, cacti, and moss have been used. In this study, Bronze (X Graptosedum) was used, and these problems were solved using the following three methods: placement and growth of virus-free plants in the terrarium; extending the diversity of plants with minimal size that can be planted in terrariums; and reducing the price of in vitro plants with minimal size by achieving large-scale production. In particular, tissue-cultured succulents were developed into a Vivorium by replacing the tissue culture container and renewing the composition of the plant. This paper suggests a new indoor horticultural field, Vivorium, that can improve the current limitations of terrariums and make them more accessible to the general public. The introduction and popularization of new indoor gardening fields with the increase in single-person households and indoor activities in the Pandemic era can also improve psychological stability among people and in the society.

• Journal of the Korean Association of Geographic Information Studies
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• v.24 no.3
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• pp.83-98
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• 2021

Urban green space is an important component for enhancing urban ecosystem health. Thus, identifying the spatial structure of urban green space is required to manage a healthy urban ecosystem. The Ministry of Environment has provided the level 3 land cover map(the highest (1m) spatial resolution map) with a total of 41 classes since 2010. However, specific urban green information such as street trees was identified just as grassland or even not classified them as a vegetated area in the map. Therefore, this study classified detailed urban green information(i.e., tree, shrub, and grass), not included in the existing level 3 land cover map, using two types of high-resolution(<1m) remote sensing data(i.e., airborne LiDAR and RGB ortho imagery) in Suwon, South Korea. U-Net, one of image segmentation deep learning approaches, was adopted to classify detailed urban green space. A total of three classification models(i.e., LRGB10, LRGB5, and RGB5) were proposed depending on the target number of classes and the types of input data. The average overall accuracies for test sites were 83.40% (LRGB10), 89.44%(LRGB5), and 74.76%(RGB5). Among three models, LRGB5, which uses both airborne LiDAR and RGB ortho imagery with 5 target classes(i.e., tree, shrub, grass, building, and the others), resulted in the best performance. The area ratio of total urban green space(based on trees, shrub, and grass information) for the entire Suwon was 45.61%(LRGB10), 43.47%(LRGB5), and 44.22%(RGB5). All models were able to provide additional 13.40% of urban tree information on average when compared to the existing level 3 land cover map. Moreover, these urban green classification results are expected to be utilized in various urban green studies or decision making processes, as it provides detailed information on urban green space.

• Journal of Mushroom
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• v.19 no.3
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• pp.200-209
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• 2021

In this study, a low-salt Lentinula edodes soybean paste (LSLESP) with improved palatability and storability relative to traditional Korean soybean paste was developed by utilizing low quality log cultivation of L. edodes. We also conducted quality characteristic analyses of spread jam made from low-salt L. edodes soybean paste (SJLLESP). The lowest salinity content and the highest L (brightness) value was found in LSLESP. According to proximate compositions analysis, crude protein, crude fat, and ash content were higher in commercial soybean paste than in LSLESP. Glucose, fructose, and maltose were the only free sugars detected in commercial soybean paste, whereas arabinose and fucose were additionally detected in LSLESP. Only two types of organic acid, were detected in common in commercially available soybean paste and LSLESP. Four types of organic acid, were detected in SJLLESP due to its added ingredients. The major free amino acids in commercially available soybean paste and LSLESP are histidine, glutamic acid, and arginine. Total amino acid, content was higher in LSLESP (54.81 mg%) than in commercial soybean paste (49.26 mg%). Total free amino acid, content in SJLLESP was 43.01 mg%. Ergosterol and β-glucan contents were highest in SJLLESP. The elevated ergosterol and β-glucan content in low-salt LSLESP relative to commercial soybean paste was significant. In conclusion, LSLESP and SJLLESP contain useful components from L. edodes, and offer the advantage of low salinity. LSLESP and SJLLESP could thus contribute to the development of health foods using L. edodes.

• Journal of the Korean Society of Radiology
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• v.15 no.5
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• pp.675-681
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• 2021

Recently, the Ministry of Education stipulates in the distance class operation regulations that student lecture evaluations for distance learning subjects should be conducted at least twice per semester and the results should be disclosed to students. Therefore, the lecture evaluation of D college was compared with the first semester of 2020 and the first semester of 2021. As for the multiple-choice evaluation result of the distance learning mid-course evaluation, the overall average of the mid-course evaluation of the distance class in the first semester of 2020 increased from 4.1819 to 4.4000 in the mid-course evaluation in the first semester of 2021.In the case of the first semester of 2020, due to Corona 19, all non-face-to-face classes were held, but in the first semester of 2021, face-to-face classes increased. The overall satisfaction level rose from 4.18 points in the first semester of 2020 to 4.39 points in the first semester of 2021. The screen composition, sound and picture quality, playback time, face appearance, lecture material provision, and frequency of use of the top 3% and bottom 3% also increased. Despite the changes caused by the LMS replacement, which was a concern, student attendance, assignments, and test submission rates also increased compared to the previous year. The null hypothesis that 'the difference between the two scores is the same' is the null hypothesis because the probability of significance is 0.000 and less than 0.05 in the case of the best 3% of the test result of the test result of the mid-course evaluation of distance classes in the first semester of 2020 and the evaluation of the intermediate lectures in the first semester of 2021. As this was rejected, it can be seen that the best score for the 2021 school year has significantly increased compared to the first semester of 2020. Also, in the case of Worst 3% or less, the significance probability is 0.000, which is less than 0.05, so the null hypothesis that 'the difference between the two scores is the same' was rejected, indicating that the Worst score for the 2021 school year was significantly higher than that for the first semester of 2020.