• 한국태양에너지학회:학술대회논문집
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• 2008.11a
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• pp.202-207
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• 2008

Measures for coping with energy shortage are being sought all over the world. Following such a phenomenon, effort to use less energy in the design of buildings and equipment are being conducted. In particular, a program to evaluate the performance of a building comes into the spotlight. However. indispensable standard wether data to estimate the exact energy consumption of a building is currently unprepared. Thus, after appling standard weather data for four weather factors which were used in previous researches to Visual DOE 4.0, we compared it with the result of the existing data and evaluated them. For the monthly cooling and heating load of our target building, we used revised data for June, July, August, and September during which cooling load is applied. When not the existing data but the revised data was used, the research shows that an average of 14.9% increased in June, August, and September except for July. Also, in a case of heating load, the result by the revised data shows a reduction of an average of 11.9% from October to April during which heating load is applied. In particular, the heating loads of all months for which the revised data was used were more low than those of the existing data. In the maximum cooling and heating load according to load factors, the loads by residents and illumination for which the revised data was used were the same as those of the existing data, but the maximum cooling loads used by the two data have a difference in structures such as walls and roofs. Through the above results, the research cannot clearly grasp which weather data influences the cooling and heating load of a building. However, in the maximum loads by the change of weather data in four factors (dry-bulb temperature, web-bulb temperature, cloud amount, and wind speed) among 14 weather factors, the research shows that 5.95% in cooling load and 27.56% in heating load increased, and these results cannot be ignored. In order to make weather data for Performing energy performance evaluation for future buildings, the flow of weather data for the Present and past should be obviously grasped.

• Proceedings of the KWS Conference
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• 2002.10a
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• pp.193-198
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• 2002

In 1his paper, applicability of laser welding to joining process of single crystal nickel base superalloy turbine blades was investigated. Because heat input of laser welding is more precisely controlled 1han TIG welding, it is possible to optimize solidification microstructure of the welds. Since in single crystal nickel base superalloy the crystal orientation have a significant effect on the strength, it is important to control the solidification microstructure in the fusion zone. A single crystal nickel base supera1loy, CMSX-4, plates were bead-on welded and butt welded using a $CO_2$ laser. The effects of microstructure and crystal orientation on properties of the weld joints were investigated. In bead-on weldling, welding directions were deviated from the base metal [100] direction by 0, 5, 15 and 30 degrees. The welds with deviation angles of 15 and 30 degrees showed fusion zone transverse cracks. As the deviation angles became larger, the fusion zone had more cracking. In the cross section microstructure, the fusion zone grains in 0 and 5 degrees welds grew epitaxially from the base metal spins except for the bead neck regions. The grains in the bead neck regions contained stray crystals. As deviation angles increased, number of the stray crystals increased. In butt welding, the declinations of the crystal orientation of the two base metals varied 0, 5 and 10 degrees. All beads had no cracks. In the 5 degrees bead, the cross section and surface microstructures showed that the fusion zone grains grew epitaxially from the base metal grains. However, the 10 degrees bead, the bead cross section and surface contained the stray crystals in the center of the welds. Orientations of the stray crystals accorded with the heat flow directions in the weld pool. When the welding direction was deviated from the base metal [100] direction, cracks appeared in the area including the stray crystals. The cracks developed along the grain boundaries of the stray crystals with high angles in the final solidification regions at the center of the welds. The fracture surfaces were covered with liquid film. The cracks, therefore, found to be solidification cracks due to the presence of low melting eutectic. As the results, in both bead-on welding and butt welding the deviation angles should be control within 5 degrees for preventing the fusion zone cracks. To investigate the mechanical properties of the weld joints, high temperature tensile tests for bead-on welds with deviation angles of 0 and 5 degrees and the butt welds with dec1ination angles of 0, 5 and 10 degrees were conducted at 1123K. The the tensile strength of all weld joints were more 1han 800MPa that is almost 80% of the tensile strength of the base metal. The strength of the laser weld joints were more than twice that of tue TIG weld joints with a filler metal of Inconel 625. The results reveals 1hat laser welding is more effective joining process for single crystal nickelbase superalloy turbine blades 1han TIG welding.

• Journal of Veterinary Clinics
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• v.23 no.4
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• pp.393-399
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• 2006

Ketamine, one of general anesthetics for human and veterinary use, is a non-competitive N-methyl-D-aspartate (NMDA) receptor antagonist which interferes with the action of excitatory amino acids. It has been reported to impair various leukocyte functions. In this study, the effect of ketamine on the oxidative burst activity (OBA) of canine peripheral blood leukocytes was examined. The OBA of canine peripheral blood phagocytes was analyzed by flow cytometry system. Ketamine at higher concentration such as $1,000{\mu}M$ exhibited a low viability of leukocytes. Thus, ketamine was used at concentration of 10 to $500{\mu}M$ showing no cytotoxic effect and high cell viability. The OBA of leukocytes in the presence or absence of latex beads was analyzed by addition of dihydrorhodamine 123. The direct treatment of ketamine revealed the inhibitory effect on the OBA of peripheral blood polymorphonuclear cells (PMN) and monocyte-rich cells but not peripheral blood mononuclear cells (PBMC) in the presence of latex beads. However, when latex beads were not added to PMN, its OBA was not inhibited by ketamine. The OBA of PMN and monocyte-rich cells but not PBMC in the presence of latex beads was also inhibited by culture supernatant from ketamine-treated- PBMC but not -PMN. But the OBA of PMN in the absence of latex beads was not inhibited by culture supernatant from PBMC treated with ketamine. Therefore, these results suggested that ketamine has the inhibitory effect on the OBA of canine peripheral blood phagocytes such as neutrophils and monocytes during phagocytic response.

• Korean Journal of Veterinary Service
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• v.31 no.3
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• pp.385-395
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• 2008

This study was carried out to investigate the residue level of fluoroquinolones in hen's general eggs and specific eggs by microbiological assay method and high performance liquid chromatography (HPLC) method. HPLC separation was carried out by reversed phase chromatography on a Symmetry $C_{18}$ (250${\times}$4.6 mm, $5{\mu}m$ particle size) with a phase composed of distilled water (containing 0.4% triethylamine and phosphoric acid) : Methanol (780 : 220, v/v), pumped isocratically at a flow rate of 1.0ml/min. A fluorescence detector was utilized with an excitation wavelength of 278nm and an emission wavelength of 456nm. The calibration curves were linear $({\gamma}^2{\geq}0.999)$ over a concentration range of $0.025{\sim}0.4{\mu}g/ml$. Average recoveries of the five fluoroquinolones in whole eggs at fortified levels of $0.05{\sim}0.2{\mu}g/g$ were ranged mean $78.1{\sim}91.7%$ and low coefficient of variation was less than 10% for all analysed samples. The limits of detection and limits of quantification for whole eggs were $1.2{\sim}6.0ng/g$ and $2.3{\sim}9.1ng/g$, respectively. Only one hen's general eggfrom chicken farm in Incheon was detected with the residual fluoroquinolones (Microbiological assay method; 1 of 47 general eggs) ; the range of residual concentration enrofloxacin was 0.12ppm. Those in food stores were detected with the residual fluoroquinolones (Microbiological assay method; 4 of 88 general eggs) ; the ranges of residual concentration enrofloxacin were $0.15{\sim}2.2 ppm$, ciprofloxacin $0.01{\sim}0.06ppm$, and hen's specific eggs (40) in food stores were not detected. For the microbiological assay method of fluoroquinolones in hen's eggs, as the results of comparative analysis, the disc diffusion method with E coli may be a little highly detected for the residual fluoroquinolones.

• Journal of Korea Water Resources Association
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• v.49 no.11
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• pp.951-959
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• 2016

This study was conducted to evaluate observed runoff data collected every 10 minutes at stream gauging stations in Jeju Island using a physically-based model, SWAT. The Hancheon watershed was selected as study area, and ephemeral stream algorithm suggested by previous research was incorporated into the model, which is able to simulate ephemeral runoff pattern of Jeju streams. Simulated runoff and runoff rates were compared to observations during 2008-2013, which showed 'very good' performance rating in Nash-Sutcliffe model efficiency (ME) and determination coefficient ($R^2$). Some observations had problems such that runoff rates were very high for some rainfall events with little amount of antecedent rainfall, and were very low or missing with much rainfall comparing to previous researches. Additionally, regression equation between precipitation and simulated runoff was generated with high degree of correlation. The equation can be utilized to simply predict reasonable runoff, or to investigate and complement the abnormal or missing data of observations on the assumption that modelling results were sufficiently reliable and satisfactory. As results, minimizing the error in calibrating the model by evaluation of observed data would be helpful to accurately model the rainfall-runoff characteristics and analyze the water balance components of watersheds in Jeju Island.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.16 no.2
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• pp.116-127
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• 2017

A fog on road is known as a weather factor that affects traffic flow. The method in order to solve the problem, recently, Variable Speed Limit(VSL) which provide reasonable speed limit by road and weather conditions in real time is introduced. However, if drivers do not comply with VSL, the road safety more decrease than without VSL because individual vehicle's speed deviation is larger than without VSL. Therefore, this paper aims to analyze to speed limit compliance and traffic characteristics under foggy conditions with and without VSL. A test using driving simulator divides into normal and foggy condition with visibilities are 200m, 150, 50~100m. The test results showed that 70 subjects's average speed mostly obeyed speed limit, but speed deviation generally declined with VSL. Especially, the speed deviation more reduced under foggy conditions. According to this study, compliance of VSL clearly rose in low visibility and VSL helped improve road safety due to reduction of speed deviation. The results of this study are expected to make use of reasonable speed limit for reference.

• Bulletin of the Korean Chemical Society
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• v.32 no.8
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• pp.2648-2656
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• 2011

A simple HPLC-DAD method was developed and validated to determine B group vitamin content (thiamine, riboflavin, nicotinamide, pantothenic acid, pyridoxine and folic acid) in supplemented food samples, i.e., infant formula, cereal, low-calorie food, a multi-vitamin pill and a vitamin drink. In this study, the most significant advantages were simultaneous determination of the six B group vitamins in various food matrices and a small number of sample treatment steps that required only an organic solvent, acetonitrile. Moreover, this method prevents reduction of column durability, because the mobile phase does not contain ion-pairing reagents. Analytes were separated on a Develosil RPAQUEOUS $C_{30}$ (4.6 mm ${\times}$ 250 mm, 5 ${\mu}M$ particle size) column with a gradient elution of acetonitrile and 20 mM phosphate buffer (pH 3.0) at a flow rate between 0.8 and 1.0 mL/min. Detection was performed at 275 nm, except for that of pantothenic acid (205 nm). The calibration curves for all six vitamins showed good linearity with correlation coefficients ($r^2$) higher than 0.995. The developed method was validated with respect to linearity, intra- and inter-day accuracy and precision, limit of quantification (LOQ), recovery and stability. The method showed good precision and accuracy, with intra- and inter-assay coefficients of variation less than 15% at all concentrations. The recovery was carried out according to the standard addition procedure, with yields ranging from 89.8 to 104.4%. This method was successfully applied to the determination of vitamin B groups in supplemented food products.

• Journal of the Korean Geographical Society
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• v.39 no.4
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• pp.495-513
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• 2004

The shape of land surface work as a cradle for various environmental processes and human activities. As spatially distributed process modelings become increasing important in current research communities, a classification system that delineates land surface into characteristic geomorphological units is a pre-requisite for sustainable land use planning and management. Existing classification systems are either morphometric or generic, which have limitations to characterize continuous ecological processes over the landscape. A new classification system was developed to delineate the land surface into different geomorphological units from Digital Elevation Models(DEMs). This model assumes that there are pedo-geomorphological units in which distinct sets of hydrological, pedological, and consequent ecological processes occur. The classification system first divides the whole landsurface into eight soil-landscape units. Possible energy and material nows over the land surface were interpreted using a continuity equation of mass flow along the hillslope, and subsequently implemented in terrain analysis procedures. The developed models were tested at a 12$\textrm{km}^2$ area in Yangpyeong-gun, Kyeongi-do, Korea. The method proposed effectively delineates land surface into distinct pedo-geomorphological units, which identify the geomorphological characteristics over a large area at a low cost. The delineated landscape units mal provide a basic information for natural resource survey and environmental modeling practices.

• Journal of Aquaculture
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• v.11 no.2
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• pp.133-140
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• 1998

A 20-week growth trial was conducted in flow-through aquarum system to investigate the practical dietary carbohydrate sources for juvenile abalone (Haliotis discus hannai). Four replicate grops of the abalone averaging 0.125g were fed one of eight diets containing 24.2% wheat flour (WF), 20% dextrin (DEX), 20% sucorse (SUC), 10% $^{\alpha}$-potato starch+10% $^{\beta}$-potato starch (ab-S), 15% $^{\alpha}$-potato starch (a-S15), 20% $^{\alpha}$-potato starch (a-S20), 25% $^{\alpha}$-potato starch (a-S25), or mixture (MIX) with practical ingredients such as soybean meal, corn gluten meal, cotton seed meal and heat flour. In addition, these formulated diets were compare with macroalgae such as dried sea mustard Undaria (D-SM) or dried sea tangle Laminaria(D-ST). Survival rate, weight gain, shell growth and soft body weight of abalone were not significantly affected by the different dietary carbohydrate sources (P>0.05), whereas those fed a-S15 diet were slightly low. These values of abalone fed D-ST were lowest (P<0.05), followed by those fed D-SM. Lipid contents of soft body from abalones fed a-S25, D-ST or D-SM were significantly lower than those of abalone fed other diets (P<0.05). These data indicate that abalone can equally utilize any carbohydrate sources used in this study.

• Korean Chemical Engineering Research
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• v.54 no.6
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• pp.806-811
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• 2016

Organosolv pretreatment is the process to frationation of lignocellulosic feedstocks to enhancement of enzymatic hydrolysis. This process has advantages that organic solvents are always easy to recover by distillation and recycled for pretreatment. The chemical recovery in organosolv pretreatment can isolate lignin as a solid material and carbohydrates as fermentable sugars. For the economic considerations, using of low-molecular-weight alcohols such as ethanol and methanol have been favored. When acid catalysts are added in organic solvent, the rate of delignification could be increased. Mineral acids (hydrochloric acid, sulfuric acid, and phosphoric acid) are good catalysts to accelerate delignification and xylan degradation. In this study, the biomass was pretreated using 40~50 wt% ethanol at $170{\sim}180^{\circ}C$ during 20~60 min. As a results, the enzymatic digestibility of 2-stage pretreatment of rigida using 50 wt% ethanol at $180^{\circ}C$ was 40.6% but that of 1-stage pretreatment was 55.4% on same conditions, therefore it is shown that the pretreatment using mixture of the organosolv and catalyst was effective than using them separately.