• Journal of Korea Water Resources Association
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• v.52 no.7
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• pp.463-473
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• 2019

This study compared the characteristics of the optimization technique and the water supply and demand forecast using K-WEAP (Korea-Water Evaluation and Planning System) model and MODSIM (Modified SIMYLD) model considering wtaer supply priority. Currently, The national water resources plan applied same priority for municipal, industrial and agricultural demand. the K-WEAP model performs the ratio allocation to satisfy the maximum satisfaction rate, whereas the MODSIM model should be applied to the water supply priority of demands. As a result of applying the priority, water shortage decreased by an average of $1,035,000m^3$ than same prioritized results. It is due to the increase of the return flow rate as the distribution of Municipal and industrial water increases. Comparing the analysis results of K-WEAP and MODSIM applying the priorities, the relative error was within 5.3% and the coefficient of determination ($R^2$) was 0.9999. In addition, if both models provide reasonable water balance analysis results, K-WEAP is superior to GUI convenience for model construction and data processing. However, MODSIM is more effective in simulation time efficiency. It is expected that it will be able to carry out analysis according to various scenarios using the model.

• Journal of Food Hygiene and Safety
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• v.34 no.1
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• pp.52-57
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• 2019

Method development and validation of decursin for the standardization of Angelica gigas Nakai as a functional ingredient and health food were accomplished. The quantitative determination method of decursin as a marker compound of aerial parts of Angelica gigas Nakai extract (AAGE) was optimized by HPLC analysis using a C18 column ($3{\times}150mm$, $3{\mu}m$) with 0.1% TFA in water and acetonitrile as the mobile phase at a flow rate of 0.5 mL/min and detection wavelength of 330 nm. The HPLC/PDA method was applied successfully to quantification of the marker compound in AAGE after validation of the method with linearity, accuracy, and precision. The method showed high linearity in the calibration curve at a coefficient of correlation ($R^2$) of 0.9994 and the limit of detection and limit of quantitation were $0.011{\mu}g/mL$ and $0.033{\mu}g/mL$, respectively. Relative standard deviation (RSD) values of data from intra- and inter-day precision were less than 1.10% and 1.13%, respectively. Recovery of decursin at 0.5, 1, 5 and $10{\mu}g/mL$ were 92.38 ~ 104.11%. These results suggest that the developed HPLC method is very useful for the determination of marker compound in AAGE to develop a health functional material.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.1
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• pp.419-425
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• 2019

The objective of this study was to investigate the cooling performance characteristics of a hybrid refrigeration system in a heavy duty vehicle. The tested hybrid refrigeration system had additionally an electric compressor besides the present mechanical compressor for selective use according to the operating conditions. The applied electric compressor was a scroll type and with 18.0 cc displacement. In order to analyze the performance characteristics of the hybrid refrigeration system with respect to the cooling capacity and Coefficient of Performance (COP), other components, including two different types of compressors, were installed and tested under various operating conditions such as compressor speed and air flow rate of the evaporator. When the electric compressor was operated at 4,500 rev/min, the cooling capacity was about 4.0kW and COP was 3.5. When the mechanical compressor was operated, whereas the cooling capacity was higher than the electric controlled compressor, COP was lower due to the larger displacement and higher power consumption. To analyze the hybrid system operating characteristics due to reasonable cooling capacity with electric compressor operation, the mechanical compressor and electric compressor were operated by turns every 10 minutes under certain system operating conditions. Because surge pressure occurred when both compressors were switched on, the operating strategy required some time to balance the system pressure.

• Journal of the Korean Society of Mineral and Energy Resources Engineers
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• v.55 no.6
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• pp.527-537
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• 2018

Column tests of a sulfate reducing bacteria (SRB) bioreactor were conducted to determine the design factors for sulfate-rich mine drainage. Various substrates were applied to the bioreactor, including cow manure and its mixture with a mushroom compost, with rice straw and limestone as subsidiary materials. This procedure provided a removal efficiency of up to 82% of the total sulfur with the mixture of cow manure (70%), mushroom compost (10%) and rice straw (20%), and higher efficiencies were observed after 2 days of retention time. In the downflow condition of the flow direction, oxygen supply and re-oxidation of the sulfates occurred, causing a decrease in sulfate removal efficiency. The addition of an inorganic sludge containing heavy metals, which was intended for production of metal-sulfides in the bioreactor, had a negative effect on the long-term operation owing to arsenic release and toxicity to the SRB. The results thus show that a bioreactor using a mixed substrate with cow manure and operating in the downflow direction could reduce sulfates and total dissolved sulfur content; this process confirms the applicability of the SRB bioreactor to sulfate-rich saline drainage.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.38 no.6
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• pp.867-878
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• 2018

As the era of AVs (Automated Vehicles) comes to a close, many researches related to AVs have been conducted. Up until now, research on traffic flow impact of AVs has been the main topic, and research on traffic management for AVs is still in beginning stage. This study analyzed the effect of Dynamic Merge Control (DMC) in manual vehicle (MV) and AV environment at work zone. Dynamic Late Merge (DLM) and DLM with Dynamic Early Merge (DEM) are compared by simulation. Simulation results showed that DLM improves travel time and work zone throughput compared to no merge control case in both MV and AV environment. In the case of additional operation of DEM, the improvement effect was not observed in MV environment, but it was improved in AV environment. As a result, DMC operation in AV environment was as effective as the improvement in transition from MV to AV environment. Therefore congestion reduction at freeway work zone by DMC will be possible in future AV environment, and the improvement of DMC can be suggested.

• Journal of Veterinary Clinics
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• v.36 no.1
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• pp.46-52
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• 2019

Pimobendan has inotropic and vasodilating effects on cardiovascular system, and pentoxifylline is known to decrease blood viscosity and improve blood flow to the heart. This study investigated the pharmacokinetics and pharmacodynamics following oral administration of pimobendan-pentoxifylline powder mixture in dogs. Eight healthy dogs were included and were divided into control (n = 4) and experimental (n = 4) groups. Vehicle powder and pimobendan-pentoxifylline powder mixture (pimobendane 0.25 mg/kg, pentoxifylline 15 mg/kg) were administrated orally to control and experimental groups, respectively. Plasma samples and measurement of echocardiographic indices were obtained for 24 hours following administration. Pimobendan and pentoxifylline concentrations were investigated using liquid chromatography-mass spectrometer (LC-MS) assay. The elimination half-life ($T_{1/2}$) were $2.65{\pm}1.42hours$ for pimobendan and $0.29{\pm}0.23hours$ for pentoxifylline. The time to reach maximum concentration ($T_{max}$) were $1.08{\pm}0.72hours$ for pimobendan and $0.29{\pm}0.14hours$ for pentoxifylline. The maximum blood concentration ($C_{max}$) were $2.83{\pm}1.50ng/mL$ for pimobendan and $1184.33{\pm}932.37ng/mL$ for pentoxifylline. Among echocardiographic indices, fractional shortening (FS), left ventricular internal diameter at end systole (LVIDs), and pre-ejection period (PEP) showed significant changes at 1-4 hours after the administration of pimobendan-pentoxifylline powder mixture. No adverse effects were observed during the investigation. This study demonstrates that pimobendan-pentoxifylline powder mixture can be used to control cardiovascular diseases in dogs.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.3
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• pp.400-406
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• 2019

This study will explore the reenactment of visual special effects used in TV dramas. The subjects of the study are images that are reproduced in visual special effects through and . Accordingly, we looked at the changes in the way TV dramas were produced according to the times, and looked at the changes in the market. Also, we looked at cases of visual special effects of Korean dramas, and looked at expressions according to the degree of completion of visual special effects. For the purpose of the analysis of the research targets, the images of reproducibility and the flow through reality were analyzed. In the case of , the period setting is realistic, but visual special effects were used to maximize the actor's safety and expression, and in the case of , the visual effects were used to maximize the aesthetic of the period background. In addition, it can be seen that the visual special effects were used for the effect of PPL on the export of images. This shows that the emphasis of reality and image montage techniques are being used to pursue hyperrealism. It is now possible to actively express and use the beauty of TV dramas rather than technical limitations. In addition, the pursuit of realism can actively express the changing times of digital age. This is an active representation of the camera's angle, lighting, and perspective that coincides with the background. The environment of video production is crucial for realistic expressions. The study examined various visual directions and applications. In TV images, we looked at reproduction, which can make a natural period of time by combining. As a follow-up study, we are going to study the changes in the new quadratic image based on the present image representation.

• The Journal of Society for e-Business Studies
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• v.23 no.3
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• pp.159-171
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• 2018

The imported foods, which are imported and sold domestically, are on the rise every year, and the scale is expected to be larger, including processing the imported raw materials. However, the origin of raw materials is indicated when declaring cargo for finished products of agricultural products, but the standardization of inspection information management system for raw materials is insufficient. In addition, there is a growing concern about the presence of residual pesticides or radioactivity in raw materials or products, and customer want to know production history information when purchasing agrifoods. It manages the hazard analysis of imported agricultural products, but most of them are global issues such as microorganisms, residual pesticides, food additives, and allergy components, etc. Therefore, it is necessary to share among the logistics entities in the entire transportation process the related data. Additionally, to do this, it needs to design an architecture and standardize business model. In this paper, it defines the architecture and the work-flow that occurs between the business process for collecting, processing, and processing information for tracking the status of imported agricultural products by steps, and develops XML message with UBL and the extracted conceptual information model. It will be easy to exchange and share information among the logistics entities through the defined standard model and it will be possible to establish visibility, reliability, safety, and freshness system for transportation of agricultural products requiring real-time management.

• Korean Journal of Radiology
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• v.19 no.6
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• pp.1161-1171
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• 2018

Objective: The aim of this study was to investigate diffusion tensor (DT) imaging-derived properties of benign oligemia, true "at risk" penumbra (TP), and the infarct core (IC) during the first 3 hours of stroke onset. Materials and Methods: The study was approved by the local animal care and use committee. DT imaging data were obtained from 14 rats after permanent middle cerebral artery occlusion (pMCAO) using a 7T magnetic resonance scanner (Bruker) in room air. Relative cerebral blood flow and apparent diffusion coefficient (ADC) maps were generated to define oligemia, TP, IC, and normal tissue (NT) every 30 minutes up to 3 hours. Relative fractional anisotropy (rFA), pure anisotropy (rq), diffusion magnitude (rL), ADC (rADC), axial diffusivity (rAD), and radial diffusivity (rRD) values were derived by comparison with the contralateral normal brain. Results: The mean volume of oligemia was $24.7{\pm}14.1mm^3$, that of TP was $81.3{\pm}62.6mm^3$, and that of IC was $123.0{\pm}85.2mm^3$ at 30 minutes after pMCAO. rFA showed an initial paradoxical 10% increase in IC and TP, and declined afterward. The rq, rL, rADC, rAD, and rRD showed an initial discrepant decrease in IC (from -24% to -36%) as compared with TP (from -7% to -13%). Significant differences (p < 0.05) in metrics, except rFA, were found between tissue subtypes in the first 2.5 hours. The rq demonstrated the best overall performance in discriminating TP from IC (accuracy = 92.6%, area under curve = 0.93) and the optimal cutoff value was -33.90%. The metric values for oligemia and NT remained similar at all time points. Conclusion: Benign oligemia is small and remains microstructurally normal under pMCAO. TP and IC show a distinct evolution of DT-derived properties within the first 3 hours of stroke onset, and are thus potentially useful in predicting the fate of ischemic brain.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.39 no.1
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• pp.183-194
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• 2019

In recent years, the risk of external flooding of major national facilities has increased significantly since 2000 due to the increase in local heavy rainfall events. For important domestic national facilities, it is necessary to analyze the risk of external flooding as flooding in major sites due to heavy rain can cause functional paralysis in major facilities and ultimately lead to massive trouble events. In order to manage the safety of main facilities and its related facilities at a high level, it is necessary to analyze the degree of disaster such as flood depth, flood flow rate, flood time and flood intensity when extreme floods (LIP) are introduced. In addition, the degree of vulnerability of these related facilities should be assessed and risk assessments should be reassessed through linkage analysis that combines the degree of disaster and vulnerability. By calculating a new flood hazard curve for the flood depth and flood intensity in major national facilities under the heavy rainfall conditions through this study, it is expected to be a basis for the waterproof design of important SOC facilities, flood prevention function design, advancement of flood prevention measures and procedures and evaluation of flood mitigation functions.