• Journal of Environmental Science International
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• v.33 no.2
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• pp.139-160
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• 2024

The community structure of benthic macroinvertebrates in the Madongho Wetland protected area and inflow river located in Goseong-gun, Gyeongsangnam-do, was investigated in 2022 and 2023. We collected and identified 3,582 individuals belonging to 7 classes, 23 orders, 51 families, and 78 species over the 2 years from six sites. Gnorimosphaeroma naktongense was the dominant species with a ratio of 20%, and Caridina denticulata denticulata was the subdominant species with a ratio of 13.32%. Predators and gathering collectors were the most abundant in the functional feeding group, while sprawlers were the most diverse and numerous in the habitual dwelling group. Diversity, richness, dominance, and evenness were calculated as the biological indices. In addition, various biological water quality indices were calculated. Most insects in the inflow rivers belonged to group I in evaluating relative resistance and resilience, showing high colony stability. The results of analyzing the correlation between salinity and substrate particle size with brackish water species showed that Gnorimosphaeroma naktongense and Hediste japonica had a significant positive correlation with salinity, while Assiminea lutea and Neomysis awatschensis had a significant positive correlation with substrate particle size. Additionally, Sinelobus kisui was found to be a new record of Korean Tanaididae in this study.

• Korean Journal of Environment and Ecology
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• v.23 no.5
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• pp.447-459
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• 2009

This study is intended to provide basic date for the efficient management of Pinus densiflora community by analyzing ecological characteristics of Pinus densiflora inhabiting Byeonsanbando National Park. According to investigations, P. densiflora community and P. densiflora-Quercus community are widely distributed, occupying 40.3% of the total area. 21 sites ($400m^2$per site) are selected for TWINSPAN analysis, and the result indicates that the whole community of P. densiflora and P. densiflora-Quercus can be classified into 8 types, and the age of P. densiflora is 40-50 years, which is similar to that of deciduous broad-leaved trees. The 8 community types are: P. densiflora community which competes with Quercus variabilis; P. densiflora community in which Fraxinus sieboldiana and Quercus serrata grow in the understory layer; P. densifloa community in which Q. serrata grow in the understory layer and Smilax china var. microphylla in the shrub layer respectively; P. densifloa community in which P. densiflora and F. sieboldiana grow in the understory layer; P. densiflora community which competes with Q. serrata and Carpinus tschonoskii; P. densiflora community which competes with Q. variabilis and Q. serrata; P. densiflora community in which Prunus sargentii grow; P. densiflora community in which Abies holophylla grow. P. densiflora community which competes with Q. variablis and C. tschonoskii seems to be in a stage of succession to deciduous broad-leaved community. The analysis indicates that Shannon diversity index is 0.2756-1.3879. It also indicates that there is a negative correlation between P. densiflora and Q. variabilis and C. tschonoskii; there is a positive correlation between P. densiflora and F. sieboldiana and Rhododendron schlippenbachii. These investigations show that the transformation of vegetation is already under way. There is a possibility that ecological succession can take place in 30.4% of the total area from P. densiflora to Quercus and deciduous broad - leaved trees. Therefore, it is recommended that the preservation and maintenance of P. densiflora be implemented by taking control of competing species which undermine the stability of P. densiflora forest community.

• The Journal of the Korea Contents Association
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• v.20 no.10
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• pp.615-629
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• 2020

Conducting Focus Group Interview (FGI), this study examined the roles and discourses of cryptocurrency's online communities and media (legacy media and YouTube), and based on this, the study proposed the direction of cryptocurrency policy. By reviewing previous literature, this study analyzed the characteristics of investors, the online community, and YouTube, which is an investment environment factor. The study figured out the purpose of use and role of the community via interviews with cryptocurrency professional investors and online community members and analyzed main discussion themes of the five top-ranked YouTube channels related to cryptocurrency with the highest number of subscribers. The results suggested that cryptocurrency's investment was led by those who are in their 20s and 30s, the investors preferred and trusted information on new media than legacy media. The online community played the role of emotional homogeneity and empathy, and YouTube mainly performed the informational role. As a result of discourse analysis and interviews, this study argued that the legal stability of cryptocurrency's policy and protection of individual investors are needed. This study's significance indicates that it used various research methods such as literature research, interviews, content analysis of community/YouTube to analyze the informational role and emotional aspects of new media and suggested policy direction of the digital new deal blockchain technology and the fairness of financial industry.

• Computers and Concrete
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• v.25 no.6
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• pp.485-495
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• 2020

This paper, presents the dynamic and stability analysis of the simply supported single walled Carbon Nanotubes (SWCNT) reinforced concrete beam on elastic-foundation using an integral first-order shear deformation beam theory. The condition of the zero shear-stress on the free surfaces of the beam is ensured by the introduction of the shear correction factors. The SWCNT reinforcement is considered to be uniform and variable according to the X, O and V forms through the thickness of the concrete beam. The effective properties of the reinforced concrete beam are calculated by employing the rule of mixture. The analytical solutions of the buckling and free vibrational behaviors are derived via Hamilton's principle and Navier method. The analytical results of the critical buckling loads and frequency parameters of the SWCNT-RC beam are presented in the form of explicit tables and graphs. Also the diverse parameters influencing the dynamic and stability behaviors of the reinforced concrete beam are discussed in detail.

• Journal of The Korean Society of Agricultural Engineers
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• v.65 no.5
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• pp.1-11
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• 2023

Due to climate change and aging of reservoirs, damage to embankment slopes is increasing. However, the safety diagnosis of the reservoir slope is mainly conducted by visual observation, and the time and economic cost are formidable to apply soil mechanical tests and slope stability analysis. Accordingly, this study presented a predicting method for the compaction and strength characteristics of the reservoir embankment soil using a portable static cone penetration test. The predicted items consisted of dry density, cohesion, and internal friction angle, which are the main factors of slope stability analysis. Portable static cone penetration tests were performed at 19 reservoir sites, and prediction equations were constructed from the correlation between penetration resistance data and test results of soil samples. The predicted dry density and strength parameters showed a correlation with test results between R² 0.40 and 0.93, and it was found to replace the test results well when used as input data for slope stability analysis (R² 0.8134 or more, RMSE 0.0320 or less). In addition, the prediction equations for the minimum safety factor of the slope were presented using the penetration resistance and gradient. As a result of comparing the predicted safety factor with the analysis results, R² 0.5125, RMSE 0.0382 in coarse-grained soil, R² 0.4182 and RMSE 0.0628 in fine-grained soil. The results of this study can be used as a way to improve the existing slope safety diagnosis method, and are expected to be used to predict the characteristics of various soils and inspect slopes.

• Journal of The Korean Society of Agricultural Engineers
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• v.66 no.1
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• pp.25-37
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• 2024

As the agricultural land use shifts from paddy to upland, ensuring reservoir water supply stability for upland crop irrigation becomes essential. The objectives of this study were to estimate the irrigation water requirements considering the upland irrigation scenario and to evaluate the reliability of the water supply from the agricultural reservoir using resilience indexes. Two study sites, Sinheung and Hwajeong, were selected, and soybean and red peppers, the most water-intensive crops, were selected as study crops, respectively. For the irrigation scenario, two irrigation methods of traditional scheduling (which irrigates all sites at once) and rotational scheduling (which distributes irrigation by districts), along with the upland conversion rate, were considered. The net irrigation requirement was estimated through a water balance analysis. The stability of the reservoir was evaluated using resilience indexes based on the simulated 10-years reservoir water levels and drought criterion. Overall, the water supply of the reservoir was evaluated as stable during the simulated 10 years, except for the one year. Compared to the two irrigation methods, rotational scheduling resulted in lower irrigation water usage in both sites, with reductions of 1.6%, and 0.3%, respectively. As the upland conversion rate increases, the water deficit could be intensified in Hwajeong with a conversion rate exceeding 50%, showing the number of deficit(ND) over the one and a rapid increase in the deficit ratio(DR). It was confirmed that the reservoir operation criteria can be enhanced by incorporating resilience indicators along with crop growth information, thus, this will be a further study.

• Korean Journal of Social Welfare
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• v.56 no.2
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• pp.261-283
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• 2004

This study verified the effectiveness of brief family education programs for schizophrenic outpatients and their families in a community social welfare center, using a pre - post test control group design. The results of this study verified that the program was effective to improve knowledge about schizophrenia, reduce feelings of rejection and anxiety about patients, and help the patients to recognize their family emotional support. Therefore, it was found in this study that the brief family education program in the community social welfare center had a positive impact on schizophrenic outpatients and their families' treatment and rehabilitation. From the results of this study, it can be seen that this program positively effects the treatment and rehabilitation of schizophrenic patients and the stability of their families. The program can also be easily utilized as a community resource. Furthermore, the results of this study can be utilized as fundamental support to suggest the need for mental health programs in community social welfare centers. This study suggested the importance of increasing the number of mental health professionals working in this arena. There is also a need to create additional supportive programs for schizophrenic outpatients and their families. Follow up care also needs to be provided to families after completing family education programs. Continuous study is needed in these areas.

• Korean Journal of Microbiology
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• v.27 no.3
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• pp.265-271
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• 1989

Bacteria isolated from Cheonsu Bay at 4 seasons were analyzed by numerical taxonomic method. Results of 48 morphological, physiological and biochemical tests showed different adaptability of bacteria to temperature in consequence with sampling season and isolated bacteria were able to survive at various environmental conditions, Identification results revealed that Enterobacteriaceae, Aeromonas, Pseudomonas and Vibrio were dominant genera in geterotrophic bacterial community. For each season, Aeromonas was most dominant in spring and autumn, Pseudomonas and Enterobacteriaceae in summer and winter, respectively. Cluster ananlysis was performed and all vacteria were clustered into 29 phenetic groups. Seasonal characteristics were distict in each group. Different physiological characteristics and species compositions for each season contribute to the stability and diversity of environmental ecosystem.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.19 no.4
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• pp.221-228
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• 2016

The gastrointestinal exposome represents the integration of all xenobiotic components and host-derived endogenous components affecting the host health, disease progression and ultimately clinical outcomes during the lifespan. The human gut microbiome as a dynamic exposome of commensalism continuously interacts with other exogenous exposome as well as host sentineling components including the immune and neuroendocrine circuit. The composition and diversity of the microbiome are established on the basis of the luminal environment (physical, chemical and biological exposome) and host surveillance at each part of the gastrointestinal lining. Whereas the chemical exposome derived from nutrients and other xenobiotics can influence the dynamics of microbiome community (the stability, diversity, or resilience), the microbiomes reciprocally alter the bioavailability and activities of the chemical exposome in the mucosa. In particular, xenobiotic metabolites by the gut microbial enzymes can be either beneficial or detrimental to the host health although xenobiotics can alter the composition and diversity of the gut microbiome. The integration of the mucosal crosstalk in the exposome determines the fate of microbiome community and host response to the etiologic factors of disease. Therefore, the network between microbiome and other mucosal exposome would provide new insights into the clinical intervention against the mucosal or systemic disorders via regulation of the gut-associated immunological, metabolic, or neuroendocrine system.

• Journal of Korean Library and Information Science Society
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• v.44 no.3
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• pp.5-27
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• 2013

The purpose of this study is to examine the characteristics and continuity of 'One Book, One City' community reading campaign in the U.S.A. An analysis of 584 'One Book' projects registered in the Library of Congress, the Center for the Books shows that this innovative model of reading campaign has been diffused through three stages: the beginning(1998-2001), the growth (2002-2006), and the second take-off(2007-present). The stability of more than fifty 'One Book' projects was confirmed and the continuing diffusion of 'One Book' model through 'The Big Read' Initiative and some projects' attempt to try new directions seem worth observing.