• Journal of the Korean Society of Safety
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• v.29 no.3
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• pp.114-120
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• 2014

The purpose of this study is to conduct the study of the combustion and thermal characteristics through transportation oil for the analysis of fire hazard. Transportation oil breaks down into fuels such as diesel for civilian demands, gasoline, DF1(diesel for military), high sulfur diesel(for marine), kerosene and JP1(for aviation), and lubricants like brake fluid, power steering oil, engine oil, and automatic and manual transmission oil. The experiments of flash point, ignition point, flame duration time, heat release rate were carried out using TAG closed cup flash point tester(AFP761), Cleveland open cup auto flash point analyzer(AFP762), KRS-RG-9000 and Dual cone calorimeter. As a result, the fuel's ignition points were lower than lubricants, especially that of gasoline was not conducted as it has below zero one. Gasoline has the highest ignition point of about $600^{\circ}C$, while the other fuels showed $400{\sim}465^{\circ}C$. For flame duration time, lubricants had over 300 seconds, but fuels had less than 300 seconds except high sulfur diesel(350 seconds). Total heat release rate ranged $287{\sim}462kW/m^2$ for lubricants and gasoline showed the highest total heat release rate, $652kW/m^2$.

• Journal of the Korean Home Economics Association
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• v.43 no.11 s.213
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• pp.127-140
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• 2005

Sanitary management performance and knowledge of employees in hospital food service was evaluated by survey questionnaire to improve their sanitary management performance, analyse the weak points of sanitary management, and determine more practical and efficient alternatives of sanitation education. For this study, we selected 6 dieticians and 250 employees working in the six general hospitals larger than 400 beds in Gyeonggi and Incheon area. The questionnaire consisted of three parts: general subjects in the nutrition division of hospitals, sanitation education of dieticians, and sanitary management performance and knowledge of employees. The average ratio of HACCP related equipment and facilities of the target hospitals was relatively high at $86.5\%$. The number of sanitation education was 1.99 times/month by regular schedule and 6.47 times/month by occasional schedule. The average dietician's inspection time of cooking was 178.77 minutes/day. The average point of sanitary management performance was 4.62/5.0, showing a relatively high grade. In each region of sanitary management performance, food treatment sanitation was marked with the highest point, at 4.85, fellowed by cleaning and sterilizing sanitation at 4.65, personnel sanitation at 4.61 point and device and utensil sanitation was ranked with the lowest point at 4.53. Sanitary management performance was affected by the number of occasional education which was highest at 6-10times/month. The mean score of sanitary knowledge was 11.17/15.0. The assigned position, type of employment, status, working career and number of occasional education affected the mean score of sanitary knowledge of employees significantly. Sanitary knowledge of employees was highest in the case that occasional education was peformed at 6-10 times/month. There was no correlation between the sanitary management performance and sanitary knowledge of employees. In contrast, there were correlations between sanitary management performance and dietician's inspection time of cooking and number of employees.

• Journal of Environmental Science International
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• v.14 no.11
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• pp.1057-1062
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• 2005

The present study investigated runoff characteristics of non-point pollutants and discharge load amount according to the land utilization in Yeinam river basin. The land utilization of target basin was divided into paddy field, dry field, forest, residential area and composition area. The study on the runoff characteristics of non-point pollutants by rainfall-runoff process showed that COD, SS and T-P had the first-flushing effect with relatively high concentration in early-stage of the rainfall-runoff process, but the T-P revealed similar runoff characteristics. Event Mean Concentration(EMC) of BOD and COD according to the land utilization revealed the range of $3.11\~15.50mg/L$ and $3.37\~33.42mg/L$, and the highest concentration of EMC corresponding to BOD and COD was detected in the paddy field. The EMC of SS showed $1.7\~305.02mg/L$ and it's highest concentration was found in the dry field. The EMC of T-N and T-P represented the highest concentration in the paddy field and dry field with range of $0.91\~8.76mg/L$ and $0.02\~0.44mg/L$.

• The Journal of Korean Academy of Prosthodontics
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• v.37 no.5
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• pp.651-657
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• 1999

This study was performed to investigate the retrievability of the cementation type implant abutments. The cements used in this study were Cavitec, Tembond and Zinc Phosphate Cement. The types of surface conditioning were no treatment, 50 microne sandblasting, 250 microne sandblasting, fine diamond finishing point and coarse diamond point. The retention of cast crown was measured with Instron Universal Testing Machine(Instron Engineering Co., U.S.A.). The results were as fellows: 1. The Maximium retention was obtained by the group of Z.P.C. cementation and Coarse diamond point surface conditioning. 2. Z.P.C. shows maximum retention, and reduced in orders Tembond, Cavitec, No cement. 3. The value of retention of surface condition was highest in coarse diamond point, lowest in no tretment. 4. The similar results were obtained between fine diamond point and 50 microne sandblasting, coarse diamond point and 250 microne sandblasting. 5. The were no direct corelation between mechanical retention and cementation retention.

• The Korean Journal of Food And Nutrition
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• v.31 no.2
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• pp.272-277
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• 2018

This research was conducted to elucidate the optimum conditions for the antibacterial activity of konjak jelly using the evolutionary operation-factorial design technique. In the first set of experiments, concentration of a coagulation agent, soaking liquid, and temperature of water were set to 0.4%, $0.6{\times}10^{-2}N$, and $65^{\circ}C$ as a central point, respectively. The highest antibacterial activity was acquired at E21, in which the number of bacteria was 1.25 log cfu/g. Because the code of changes in the main effect was (-), it could be decided that the central point of the first set was not the optimum point. Although antibacterial activity in the second set was improved, the values of the main effect were higher than that of changes in the mean effect. The central point of third set was concentration of coagulation agent 0.8%, concentration of soaking liquid $1.0{\times}10^{-2}N$, and temperature of water $65^{\circ}C$. It was found that the antibacterial activity of central point in the third set was highest among all the tested set. Further, all the necessary conditions were appropriate to reach the optimum condition. The antibacterial activity of the central point in third set was more than 1,000 times higher than that of E11, in first set.

• Korean Journal of Plant Resources
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• v.20 no.6
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• pp.548-552
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• 2007

This research is the basic research to develop new anti-inflammatory medicine by feeding Scutellariae Radix extract to lipopolysaccharide(LPS) exposed rats, and analyzed it's effect on inflammatory response by LPS derivation. As a result, Plasma interleukin-$1\beta(IL-1\beta)$ and Plasma interleukin-6(IL-6) concentration showed the highest point at 5h after LPS injection, and in this time, the concentration of $IL-1\beta$ and IL-6 in the Scutellariae Radix extract groups at 200mg/kg and 300mg/kg showed lower values than that of control group. Plasma tumor necrosis $factor-\alpha(TNF-\alpha)$ concentration after LPS injection showed the highest point at 2h and showed similar level till at 5h. $TNF-\alpha$ concentration at 2h after LPS injection showed the low value only in the Scutellariae Radix extract 300mg/kg group compared to others, and in 5h, the all Scutellariae Radix extract groups showed lower value than that of the control group. Plasma interleukin-10(IL-10) concentration increased at 2h after LPS injection and reached the highest at 5h. After LPS injection the IL-10 concentration at 2h, the Scutellariae Radix extract injection group at 300mg/kg showed higher value than that of the others, and in 5h after LPS injection, Scutellariae Radix extract 200mg and 300mg groups showed higher value than the control group. Concluding from the above results, in inflammatory response by LPS derivation, the Scutellariae Radix gives positive effect.

• Journal of Hydrogen and New Energy
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• v.33 no.6
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• pp.692-698
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• 2022

With the expansion of domestic hydrogen fuelling station infrastructure, it is necessary to secure reliability among hydrogen traders, and for this, technology to accurately measure hydrogen is important. In this study, 4 types of hydrogen trading volume calculation models (model 1-4) were presented to improve the accuracy of the hydrogen trading volume. In order to obtain the reference value of model 4, and experiment was conducted using a flow rate measurement equipment, and the error rate of the calculated value for each model was compared and analyzed. As a result, model 1 had the lowest metering accuracy, model 2 had the second highest metering accuracy and model 3 had the highest metering accuracy until a certain point. But after the point, model 2 had the highest metering accuracy and model 3 had the second metering accuracy.

• Journal of ILASS-Korea
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• v.13 no.2
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• pp.79-84
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• 2008

The correlations for cross-flow have not been well established, because of the complexity of breakup and atomization mechanism. A study was performed to investigate the characteristics of spray behaviour of liquid jet in the bag breakup regime injected into low-speed cross-flow with the pressure single-hole nozzle. The shadow-graphy method was used for the cross-flow jet visualization. The experimental variables of liquid jet were nozzle diameter $(0.3mm{\sim}1.0mm)$, injection pressure $(50kPa{\sim}150kPa)$, and the velocity of cross-flow $(27m/s{\sim}42m/s)$. The highest penetration trajectories of liquid jet are governed by the momentum ratio $({\rho}_{\iota}U_{\iota}^2/{\rho}_aU_{cross}^2)$ rather than the Weber number and the new empirical equations of the highest penetration trajectory and breakup point at low-speed corss-flow are established.

• Journal of Korean Society of Water and Wastewater
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• v.23 no.5
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• pp.631-636
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• 2009

This study has its intention to investigate the water quality of non-point source which is runoff from roads. We have classified and selected twelve sites as city road, industrial road, national road and mountain road by considering their traffic volume and surroundings. Water quality was analyzed based on BOD, COD, SS, T-N and T-P and the concentrations were measured by sampling after rainfall with the interval of 10 minutes, 20 minutes, and 30 minutes. BOD was the highest in city road with 57.6 mg/L and the lowest in mountain road with 45.0 mg/L. For COD, the highest concentration in industrial road was 146.5 mg/L and the lowest was in mountain road with 98.0 mg/L. The run off concentration of SS was up to maximum 630.0 mg/L (average 280.4 mg/L) which was remarkable compared to other types of road. It showed its lowest concentration in national road with 76.0 mg/L. T-N and T-P were the highest in industrial road and the lowest in mountain road. We found out that the runoff concentration was high with large amount of traffic volume and it seemed to be high in city road and industrial road where they were largely affected by their surroundings. Relatively, national road and mountain road seemed to show low concentration as they have less traffic volume and less affected by their surroundings.

• Journal of Environmental Science International
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• v.26 no.8
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• pp.881-891
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• 2017

In this study, the discharge loads of non-point pollution sources were analyzed using a Hydrologic Simulation Program-Fortran (HSPF) model for 46 sub-watersheds in order to guide the management plan for water and streams passing through the city. The results using HSPF showed good applicability in comparison to point measurements, which were based on BOD, TP, and TN. The mean value of the BOD loads was $4.08kg/km^2$ per day, and the highest level of BOD was $17.75kg/km^2$ per day at Namri. Three potential areas of high priority for the installment of constructed wetlands were selected in order to reduce non-point pollution sources based on BOD loads and on environmental and economic conditions. The results for these scenarios indicated a maximum rate of reduction in BOD of 39.12% within the proposed constructed wetlands.