• Korean Journal of Ichthyology
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• v.34 no.2
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• pp.113-118
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• 2022

The feeding habits of sandfish, Arctoscopus japonicus were studied using 781 specimens collected by Eastern Sea Danish and gill net from January 2020 to December 2021 in the coastal waters of East Sea, Korea. The size of the specimens ranged from 14.8 to 25.4 cm in total length. A. japonicus were fed mainly on amphipods that constituted 54.7% in IRI. Cephalopods were the second largest prey component. The diets also include small quantities of euphausiids, crabs, shrimps, fishes, and worms. The diet composition of A. japonicus showed changes in season. The cephalopods feeding rate was highest in summer, whereas the proportion of euphausiids was higher in spring than in other seasons. The proportion of cephalopods has increased as the body size of A. japonicus increased, whereas the proportion of amphipods and euphausiids decreased gradually. As the body size of A. japonicus increased the mean weight of prey per the stomach (mW/ST) tended to increase significantly (One-way ANOVA, P<0.05).

• Journal of Korean Tunnelling and Underground Space Association
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• v.24 no.4
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• pp.327-339
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• 2022

The purpose of this study is to present the effective smoke control flow rate and mode for securing safety through quantitative risk assessment according to the smoke control flow rate and mode (supply or exhaust) of the platform when a train fire occurs at the subway platform. To this end, a fire outbreak scenario was created using a side platform with a central staircase as a model and fire analysis was performed for each scenario to compare and analyze fire propagation characteristics and ASET, evacuation analysis was performed to predict the number of deaths. In addition, a fire accident rate (F)/number of deaths (N) diagram (F/N diagram) was prepared for each scenario to compare and evaluate the risk according to the smoke control flow rate and mode. In the ASET analysis of harmful factors, carbon monoxide, temperature, and visible distance determined by performance-oriented design methods and standards for firefighting facilities, the effect of visible distance is the largest, In the case where the delay in entering the platform of the fire train was not taken into account, the ASET was analyzed to be about 800 seconds when the air flow rate was 4 × 833 m³/min. The estimated number of deaths varies greatly depending on the location of the vehicle of fire train, In the case of a fire occurring in a vehicle adjacent to the stairs, it is shown that the increase is up to three times that of the vehicle in the lead. In addition, when the smoke control flow rate increases, the number of fatalities decreases, and the reduction rate of the air supply method rather than the exhaust method increases. When the supply flow rate is 4 × 833 m³/min, the expected number of deaths is reduced to 13% compared to the case where ventilation is not performed. As a result of the risk assessment, it is found that the current social risk assessment criteria are satisfied when smoke control is performed, and the number of deaths is the flow rate 4 × 833 m³/min when smoke control is performed at 29.9 people in 10,000 year, It was analyzed that it decreased to 4.36 people.

• Journal of Korea Port Economic Association
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• v.38 no.2
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• pp.81-93
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• 2022

Since 2008, China's shipping industry has been in a slump, with shipbuilding orders falling sharply, and high-growth excess capacity has become increasingly apparent, leaving many firms with sharply reduced orders at risk of bankruptcy and shutdown. To ensure the development of the shipbuilding industry and enhance the international competitiveness of the shipbuilding industry, it is necessary to analyze the present situation of the shipbuilding industry and the financial situation of the shipbuilding enterprises. And analyzing the problems faced by enterprises from the perspective of capital structure is very meaningful to the shipbuilders with high capital operation. We are trying to analyze the determinants of capital structure of China's shipbuilding listed companies. 30 listed Chinese shipbuilding and listed companies have been designated as sample companies that can obtain financial statements for 13 consecutive years. They also divided 30 sample companies into shipbuilding, shipbuilding-related manufacturing, and shipbuilding-related transportation. Dependent variable is the debt level of the year, independent variable includes the debt level of the previous year, fixed asset ratio, profitability ratio, depreciation cost ratio and asset size. The regression model of the panel used to analyze determinants is capital structure. The results of the empirical analysis are as follows. First, a fixed-effect model for the entire entity showed that the debt-to-equity ratio and the size of the asset in the previous period had a positive effect on the debt-to-equity ratio in the current period. Second, the impact of the profitability ratio on the debt level in the prior term also supports the capital procurement ranking theory rather than the static counter-conflict theory. Third, it was shown that the ratio of the depreciation of the prior term, which replaces the non-liability tax effect, affects the debt-to-equity ratio in the current period.

• Korean Journal of Organic Agriculture
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• v.29 no.4
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• pp.601-612
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• 2021

This study was conducted to evaluate the appropriate sowing method and mixture seeding rate on germination of Kentucky bluegrass (Poa pratensis L.) and white clover (Trifolium repens L.). The experimental design includes two sowing methods and six mixed seeding per each method: BT₁:BP₀ (broadcast seeding; B, Trifolium repens; T, Poa pratensis; P), BT₁:BP₂, BT₁:BP₃, BT₃:BT₁, BT₂:BP₁, BT₀:BP₁ and ST₁:SP₀ (spot seeding; S), ST₁:SP₂, ST₁:SP₃, ST₃:ST₁, ST₂:SP₁, ST₀:SP₁. The germination was the highest for both species when the seeding rate was higher than other species. In overall, the germination of white clover was higher and faster than Kentucky bluegrass. Two plots, BT₂:BP₁, ST₁:ST₂, were retained the balanced proportion of the germination rate. Therefore, It was suggested, for maintaining the balanced field, it is better to seed white clover twice Kentucky bluegrass on broadcast seeding and Kentucky bluegrass twice white clover on spot seeding. In regard of sowing method, broadcast seeding is better than spot seeding in terms of increasing the germination. It is necessary to supplement the result for real application by long-term monitoring.

• Journal of Korea Water Resources Association
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• v.54 no.11
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• pp.875-889
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• 2021

This study compares and analyzes the Soil and Water Assessment Tool (SWAT) and Terra MODIS (Moderate Resolution Imaging Spectroradiometer) as coniferous, deciduous and mixed forest with Yongdam Dam upstream (904.4 km²). The hydrologic evaluation period was set to 10 years from 2010 to 2019, and the applicability of the 8-day MOD15A2 Leaf Area Index (LAI) data, 3 TDR (Time Domain Reflectometry) (GB, JC, CC), and 1 Flux Tower (DU) evaporation volume (YDD) data was simulated. As a result, the R² of coniferous forest, deciduous forest and mixed forest are 0.95, 0.89, 0.90, soil moisture and evaportranspiration stations R² were analyzed at 0.50 to 0.55 and 0.51, respectively, with R² at 0.74, RMSE 2.75 mm/day, NSE 0.70 and PBIAS 14.3% for Yongdam inflow. Based on the calibrated and validated watersheds, the annual average evaportranspiration was calculated as coniferous 469.7 mm, deciduous 501. mm and 511.5 mm mixed forest, total runoff were estimated at coniferous 909.8 mm, deciduous 860.6 mm and 864.2 mm mixed forest. In the case of annual average evaportranspiration, it was evaluated that deciduous were high, but in the case of streamflow, it was evaluated that coniferous were high. Unlike other hydrologic with similar patterns throughout the year, the average annual evapotranspiration was about 7% higher than coniferous due to the higher evapotranspiration of deciduous with high leaf area index in summer and fall. In addition, deciduous were 9% and 6% higher for surface runoff and lateral flow, but the groundwater of coniferous was 77% higher. Therefore, it was confirmed that the total runoff was in order of coniferous, mixed forest, and deciduous.

• Journal of the Society of Disaster Information
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• v.17 no.4
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• pp.864-881
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• 2021

Purpose: This study aims is to provide a total care solution preventing disaster based on Big Data and AI technology and to service safety considered by individual situations and various risk characteristics. The purpose is to suggest a method that customized comprehensive index services to prevent and respond to safety accidents for calculating the living safety index that quantitatively represent individual safety levels in relation to daily life safety. Method: In this study, we use method of mixing AHP(Analysis Hierarchy Process) and Likert Scale that extracted from consensus formation model of the expert group. We organize evaluation items that can evaluate life safety prevention services into risk indicators, vulnerability indicators, and prevention indicators. And We made up AHP hierarchical structure according to the AHP decision methodology and proposed a method to calculate relative weights between evaluation criteria through pairwise comparison of each level item. In addition, in consideration of the expansion of life safety prevention services in the future, the Likert scale is used instead of the AHP pair comparison and the weights between individual services are calculated. Result: We obtain result that is weights for life safety prevention services and reflected them in the individual risk index calculated through the artificial intelligence prediction model of life safety prevention services, so the comprehensive index was calculated. Conclusion: In order to apply the implemented model, a test environment consisting of a life safety prevention service app and platform was built, and the efficacy of the function was evaluated based on the user scenario. Through this, the life safety index presented in this study was confirmed to support the golden time for diagnosis, response and prevention of safety risks by comprehensively indication the user's current safety level.

• Korean Journal of Poultry Science
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• v.49 no.1
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• pp.1-8
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• 2022

We investigated the effects of stunning methods and gas treatments during slaughter on the quality characteristics of chicken breast and small intestine. Broilers (Ross 308) were stunned and slaughtered using halal, CO₂, or N₂ gas stunning methods (for 10 birds). After slaughter, the pH, proximate composition, color, water-holding capacity, cooking loss, and shear force of chicken breast muscle and small intestine were determined. Compared with the halal treatment, CO₂ treatment resulted in higher pH and lower cooking loss (P<0.05), and the pH, color, and shear force of chicken breast muscle with N₂ treatment were similar to those of the halal treatment (P>0.05). Compared with the halal treatment, the gas treatments resulted in lower pH and lightness and higher redness, yellowness, thickness, and shear force of the small intestine (P<0.05). However, compared with the CO₂ treatment, the N₂ treatment resulted in lower pH, redness, and yellowness, and higher lightness, thickness, and shear force. Overall, compared with the halal method, our results suggest that the use of N₂ gas suppresses the discoloration and deterioration of the texture of chicken meat and small intestine caused by CO₂ gas treatment in the gas stunning method.

• Korean Journal of Environment and Ecology
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• v.36 no.1
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• pp.102-111
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• 2022

Among protected areas, National Parks are rich in biodiversity, and the benefits of ecosystem services provided to human are higher than the others. Ecosystem service evaluation is being used to manage the value of national parks based on objective and scientific data. Ecosystem services are classified into four services: supporting, provisioning, regulating and cultural. The purpose of this study is to evaluate habitat quality among supporting services. Habitat Quality Model of InVEST was used to analyze. The coefficients of sensitivity and habitat initial value were reset by reflecting prior studies and the actual conditions of protected areas. Habitat quality of 21 national parks except Hallasan National Park was analyzed and mapped. The value of habitat quality was evaluated to be between 0 and 1, and the closer it is to 1, the more natural it is. As a result of habitat quality analysis, Seoraksan and Taebaeksan National Parks (0.90), Jirisan and Odaesan National Parks (0.89), and Sobaeksan National Park (0.88) were found to be the highest in the order. As a result of comparing the area and habitat quality of 18 national parks except for coastal-marine national parks, the larger the area, the higher the overall habitat quality. Comparing the value of habitat quality of each zone, the value of habitat quality was high in the order of the park nature preservation zone, the park nature environmental zone, the park cultural heritage zone, and the park village zone. Considering both the analysis of habitat quality and the legal regulations for each zone of use, it is judged that the more artificial acts are restricted, the higher the habitat quality. This study is meaningful in analyzing habitat quality of 21 National Parks by readjusting the parameters according to the situation of protected areas in Korea. It is expected to be easy to intuitively understand through accurate data and mapping, and will be useful in making policy decisions regarding the development and preservation of protected areas in the future.

• Pediatric Infection and Vaccine
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• v.28 no.3
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• pp.133-143
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• 2021

Purpose: This study aimed to determine the incidence of central line-associated bloodstream infection (CLABSI) in the neonatal intensive care unit (NICU), evaluate the patients' clinical characteristics, and identify the etiologic agents for guidance in prevention and treatment. Methods: A retrospective chart review study of infants classified as having CLABSI was conducted at the NICU of Seoul National University Bundang Hospital from January 2016 to December 2020. Results: Of the 45 infants, 53 had CLABSIs within a follow-up period of 18,622 catheter days. The incidence of CLABSIs was 2.85 per 1,000 catheter days. The most common catheter type was a peripherally inserted central catheter (n=47, 81%). A total of 57 pathogens were isolated, of which 57.9% (n=33) were Gram-positive bacteria, 36.8% (n=21) were Gram-negative bacteria, and 5.3% (n=3) were Candida spp. The most common pathogens were Staphylococcus aureus (n=12, 21%) and coagulase-negative staphylococci (n=12, 21%), followed by Klebsiella aerogenes (n=8, 14%). The median duration of bacteremia was 2 days, and 19 episodes showed bacteremia for 3 days or more. The mortality rate of infants within 14 days of CLABSI was 13.3% (n=6). Conclusions: This study analyzed the incidence of CLABSI and the distribution of pathogens in the NICU. Continuous monitoring of CLABSI based on active surveillance serves as guidance for empiric antibiotic use and also serves as a tool to assess the necessity for implementation of prevention strategies and their impact.

• Ecology and Resilient Infrastructure
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• v.9 no.1
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• pp.68-76
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• 2022

In this study, the Habitat Suitability Index (HSI) was calculated in the Miho stream of the Geum river system, and the environmental ecological flow by point was evaluated. Two points (St.3 and St.8) representing the up and downstream of Miho Stream were selected, in order to calculate the Habitat Suitability Index, the depth and velocity at point where each species is appeared were investigated. The Habitat Suitability Index (HSI) was calculated by the Washington Department of Fish and Wildlife (WDFW) method using the number collected by water depth and velocity section and the results of the flow rate survey. Two target species were selected in this study; dominant species and swimming species sensitive to flow. In the case of a single species of Zacco platypus, the water depth was 0.1 - 0.5 m and the velocity was 0.2 - 0.5 m/s. For species of swimming fish, the water depth was 0.2 - 0.5 m and the velocity was 0.2 - 0.5 m/s. The discharge-Weighted Useable Area (WUA) relationship curve and habitat suitability distribution were simulated at the Miho Stream points St.3 and St.8. At the upstream St.3 of Miho Stream, the optimal discharge was simulated as 4.0 m³/s for swimming fishes and 2.7 m³/s for Zacco platypus. At the downstream point of St.8, species of swimming fish were simulated as 8.8 m³/s and Zacco platypus was simulated as 7.6 m³/s. In both points, the optimal discharge of swimming fish was over estimated. This is a result that the Habitat Suitability Index for swimming fish requires a faster flow rate than the habitat conditions of the Zacco platypus. In the calculation of the minimum discharge, the discharge of Zacco platypus is smaller and is evaluated to provide more Weighted Useable Area. In the case of swimming fishes, narrow range of depth and velocity increases the required discharge and relatively decreases the Weighted Useable Area. Therefore, when calculating the Habitat Suitability Index for swimming fishes, it is more advantageous to calculate the index including the habitat of all fish species than to narrow the range.