• FLOWER RESEARCH JOURNAL
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• v.16 no.1
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• pp.63-70
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• 2008

This experiment was conducted to acquire the basic data necessary for the artificial pond greening. Eighty four hydrophytes collected from 11 domestic small ponds and a farm were used in this experiment. The size of the artificial pond used was $6m{\times}3m{\times}1.5m(length{\times}width{\times}depth)$. Twelve months after planting, species were selected for their high ornamental values and tissue contents of N and P in each month. Tissue contents of N in Trapha nantan, Nymphoides indica, Nymphaea hybrid, and Murdannia keisak were high. Tissue contents of P in Monochoria vaginalis and Murdannia keisak were also high. The pH of artificial pond stabilized at a 6.8~7.6 range from May 2005 to March 2007. The EC was low in summer and high in autumn. From April to October, 5, 19, 23, 32, 31, 28, and 26 species, respectively, were selected for artificial pond greening. One year after planting, vegetation changed from 78 species (Potamogeton octqandrus, Salvinia natans, Potamogeton malaianus, etc.) to 38 species (Scirpus tarbernaemontani, Scirpus karuizawensis, Scirpus triqueter, etc.). Species diversity in the artificial pond was as follows, indicating it being a stabilized artificial pond; 38 species, 1,437 total number of plants, species richness index of 11.72, and maximum diversity index of 0.97.

• Journal of the Korea Organic Resources Recycling Association
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• v.27 no.2
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• pp.41-49
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• 2019

Livestock manure is a significant source for greenhouse gas (GHG) emission, and a huge amount of GHG emission is generated during its storage. In the present work, lowering temperature was attempted to mitigate methane ($CH_4$) emission from cattle manure (CM) with high solid content. CM was stored for 60 d at $15-35^{\circ}C$ ($5^{\circ}C$ interval). $CH_4$ emission reached $63.6{\pm}3.6kg\;CO_2\;eq./ton\;CM$ at $35^{\circ}C$, which was reduced to $51.6{\pm}1.8$, $24.1{\pm}4.4$, $14.9{\pm}0.5$, and $3.7{\pm}0.1kg\;CO_2\;eq./ton\;CM$ at 30, 25, 20, and $15^{\circ}C$, respectively. After storage, 30% of COD reduction was observed in the CM stored at $35^{\circ}C$, while the COD removal decreased to only 6% at $15^{\circ}C$. It was found that only 3-11% of COD removal was done by anaerobic process, while the rest of COD removal was done by aerobic biological process. Methanobrevibacter and Methanolobus were found to be the dominant species in the CM, and the dominance of Methanolobus psychrophilus increased at lower storage temperature. Specific methanogenic activity test results showed that the inhibition by low temperature was temporal.

• Journal of Korea Water Resources Association
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• v.55 no.9
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• pp.687-700
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• 2022

For comprehensively assessment the water resources performance of multi-purpose dams and water supply dams in South Korea, a methodology was proposed to utilize the durational reliability along with the integrated auxiliary indicators including resiliency, dimensionless vulnerability, water resource efficiency, specific inflow, and specific water supply. In addition, for the purpose of sustainable dam operation in the future, a plan to grade the water resources performance was presented to periodically evaluate the performance and determine the priority of each dam's structural or non-structural planning according to the evaluation results. As major results, in the case of Sumjingang Dam, the durational reliability was 99.0%, but the integrated auxiliary index was the lowest of 44 points, which was 5th grade. This means that despite the current high reliability, hydrological changes due to future climate change or regional change of water demand-supply balance can have significant impacts on the water resources performances. In contrast, the Chungju Dam with a durational reliability of 93.0%, which is below the average among all multi-purpose dams, shows the 76 points of the integrated auxiliary index, which is 3^rd highest following the Soyanggang Dam and the Namgang Dam. Nevertheless, due to the size of the basin, the specific inflow is sufficiently high as 185%, so the actual performance could be evaluated relatively high. The water supply dams designed for a single purpose tend to be evaluated relatively high because they have a high proportion of industrial and municipal water supply and have enough room for the supply capacity.

• Journal of Applied Biological Chemistry
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• v.65 no.4
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• pp.269-275
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• 2022

Betula platyphylla extract includes various materials which showed biological activity such as terpenoids. For this reason, Betula platyphylla extract has been used to alleviate inflammation. In this study, extract of Betula platyphylla was obtained and purified using several solvents and evaluated whether they showed effect on prevention of hair loss. Cell cytotoxicity assay was performed to investigate the effect of extracts on cell proliferation. Western blotting was performed to observe the changes in expression of several related growth factors such as β-catenin, VEGF, IGF1, and cyclin D. Also, 5-α-reductase activity was measured. The ethyl acetate extract was divided into four partial extracts and named as H3-1, H3-2, H3-3, and H3-4. The H3-2 extract showed proliferation activity of human derma papilla cell and increased the protein expression of several related growth factors such as β-catenin, VEGF, IGF1, and cyclin D, comparable to the effect of Ethyl 3,4,5-Trimethoxy Benzoate (ETB)and Lupeol (LPO). Moreover, we found that the fraction H3 was shown to decrease 5-α-reductase activity while ETB and LPO had no significant effect on 5-α-reductase activity.

• KDI Journal of Economic Policy
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• v.26 no.2
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• pp.179-208
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• 2004

With the outbreak of the financial crisis in mid-1997, the Korean government has removed a majority of M&A-related regulations in order to facilitate M&A transactions. This was based upon the belief that M&As are one of the most efficient ways to restructure financially distressed firms compared to other government-driven restructuring programs. In this paper, we try to empirically assess the role of M&A in restructuring distressed firms in Korea following the financial crisis. In doing so, three empirical analyses have been conducted. The first analysis attempts to identify financial characteristics of the insolvent M&A targets. The second exercise directly tests the change in performance of insolvent M&A targets before and after such M&A transactions. The third analysis is a more general assessment on the role of M&A transactions to determine if being involved in an M&A transaction (regardless of its motivate) has reduced the probability of becoming insolvent in the future. Overall, we find some evidence supporting that M&A activities after the financial crisis have played a positive role in restructuring financially distressed firms in Korea.

• Journal of Digital Convergence
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• v.18 no.2
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• pp.235-247
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• 2020

The Mutual Financial Cooperatives(MFCs) in Korea need to make efforts to increase efficiency and productivity in order to secure stable and sustainable growth and competitiveness. Therefore, this study analyzes the efficiency and productivity of MFCs from 2012 to 2018 and suggests some implications. The methodology employed is a Dynamic-Network Slacks-Based Measure(DNSBM) Model. The findings from an empirical study include that first, on average efficiency scores of the institutions, NH(0.225) showed the highest overall efficiency, and followed by SH(0.128) and MG(0.126). After 2015, most of the MFCs' efficiency scores had risen until to 2018. Second, in divisional analysis, the inefficiency in creating the high profitability-stage had been greater than establishing-funds-stage. Third, in projection analysis of Division 2, the inefficiency of the output factors such as interest income and operating income was severe. Fourth, the results from the Malmquist Productivity Index analysis of Division 1 of the fist-stage illustrate that all three MFCs showed minus catch-up effects. Also, a soundness from reducing bad loans and expansion of loans in combination with generating various ways of creating profits besides the interest income is urgently needed for Korean MFCs.

• Journal of the Korea Convergence Society
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• v.12 no.6
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• pp.197-203
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• 2021

In this study, to develop a higher value-added makgeolli, the Korean traditional rice wine were made of four kinds of raw material cereals (wheat flour, puffed rice, non-glutinous rice, and glutinous rice). To investigate the development potential of makgeolli as functional materials, their physicochemical characteristics, phenol, flavonoid, and vitamin contents, and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid)(ABTS) radical scavenging activity were evaluated. Puffed rice makgeolli and non-glutinous rice makgeolli among four types of makgeolli were higher contents of alcohol (16-16.5%). Of four types of makgeolli, puffed rice makgeolli showed 5.2±0.06 mg GAE/mL, the highest level content of total phenol, and flavonoid contents of them were similarly high, with a level of 470-490 ㎍ QE/mL. Puffed rice makgeolli containing the highest level content of total phenol resulted in 81.5%, the highest activity of ABTS radical scavenging. These results suggest that puffed rice may be an effective raw material for makgeolli to be developed the antioxidant functional materials.

• Journal of Navigation and Port Research
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• v.46 no.3
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• pp.168-178
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• 2022

In this study, the resistance test, the vertical static angle of the attack test and VPMM test will be conducted to estimate the maneuverability of underwater vehicles with ahead propeller. The vertical static test will be conducted within the range of -40deg to 40deg, to investigate the cross-flow drag at high incidence angles. The tests will be conducted by dividing the propeller rotation into a case in which the propeller rotates at a specific rpm, and a case in which the propeller rotates naturally, according to the towing speed. Hydrodynamic coefficients of vertical direction will be estimated by the captive model tests. Additionally, the vertical dynamic stability index based on estimated hydrodynamic coefficients will be calculated and the impact of the propeller revolution state on the index will be investigated. The results are expected to be used as reference test data for underwater vehicles with ahead propeller.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.15 no.5
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• pp.328-334
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• 2022

The process that one may consciously focuses on necessary stimulation among tremendous amount of stimulation through human sensory systems is called attention in psychology. It is known that the attention can be affected by many factors such as room temperatures, humidity level, etc. In the field of sports science, ice packs are widely used for recovery from exercise fatigue providing fast heat transfer by conduction. However, the effect on attention by so-called iced-pack-cooling has not been tested. This research focuses on the attention levels when one is provided with a special cooling pad on their dorsal and lateral cervices. 40 subjects were divided into four groups and their attention level was evaluated based on the exposure conditions of combinations in reading and light walking with and without the cooling pad. The Frankfruter Aufmerksamkeits-Inventar, FAIR was used to evaluate the attention levels; the performance index, quality index, and continuity index consist of the FAIR test indicating the selectiveness of the attention, correctness of the attention, and maintaining term of the attention, respectively. Analysis of variance was carried out for those variables and post-hoc if applicable. When visual attention is constantly used for reading and studying, application of conductive heat transfer by the cooling pads is significantly helpful for improvement in selectiveness of the attention and maintaining terms of the attention levels. Also, light walking yielded improvement in selectiveness of the attention and maintaining terms of the attention levels; however one should presupposedly consider the loss of reading time.

• Clinical and Experimental Pediatrics
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• v.50 no.10
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• pp.987-994
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• 2007

Purpose : This study investigated the clinical significance of AN in children and adolescents with obesity induced metabolic complications. Methods : Forty-nine patients who had obesity induced metabolic complications were participated in this cross-sectional study. Obesity induced metabolic complications are as follows: hypertension, dyslipidemia, impaired fasting glucose (IFG), impaired glucose tolerance (IGT), nonalcoholic steatohepatitis (NASH), homeostasis model assessment of insulin resistance (HOMA-IR)>3.16. Clinical characteristics, such as, age, percentage-weight-for-height (PWH), pubertal status, blood pressure (BP), fasting plasma insulin level, fasting and post-oral glucose tolerance test 2-hour glucose levels, liver function test, lipid profile, HOMA-IR were compared according to the presence of AN. Results : Sixty-five percent of patients had AN, 57.1% NASH, 57.1% dyslipidemia, 55.1% hypertension, 46.9% IFG, 24.5% HOMA-IR>3.16 and 16.2% IGT. The patients who were moderately to severely obese with AN had higher incidence of IGT and HOMA-IR>3.16. The patients with AN had significantly higher diastolic BP ($79.4{\pm}6.9$ vs $75.4{\pm}5.6mmHg$), fasting levels of plasma insulin ($10.6{\pm}6.0$ vs $6.2{\pm}5.4{\mu}IU/mL$), HOMA-IR index ($2.6{\pm}1.4$ vs $1.4{\pm}1.3$) and PWH ($42.4{\pm}13.0$ vs $34.3{\pm}1.8%$). The increasing tendency for the presence of AN was significantly related to the cumulative number of obesity induced metabolic complications. Binary logistic regression analysis revealed that the presence of AN was significantly associated with fasting plasma insulin level, PWH and IFG. Conclusion : AN could be useful as a clinical surrogate of obesity induced metabolic complications.