• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.18 no.7
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• pp.549-555
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• 2006

In the present study, sterilizing and antibacterial performance tests of Polybutylene pipe with nano-silver were carried out in the testing bench of water supply facilities. Experimental results show that the average sterilizing and antibacterial rate of two micro-biological samples such as E. coli and S. aureus is about 90% in case of stillness experimental condition and 99% in case of flowing experimental condition, when elapsed time is 120 hours and 3 hours, respectively. Experimental results also show that the supply water velocity in nano-silver Polybutylene pipe varies from 1 m/s to 1.5 m/s, the elapsed time needed sterilizing rate reach to 100% decreases.

• Korean Journal of Veterinary Service
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• v.38 no.4
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• pp.211-220
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• 2015

Many chemical disinfectants are using to protect the foot and mouth disease (FMD) and avian influenza (AI) in Korea since 2000. This study was performed to confirm disinfective ability of commercialized chemical disinfectants and to investigate the sterilizing ability of E-ball as alterative to chemical disinfectants. 4 kinds of acidulant, 3 kinds of aldehyde, 1 kind of oxidizer and 300 g of E-ball were used in this study. Dilution rate of disinfective power of all chemical disinfectants were to 200 times. The sterilizing ability of aldehydes were better than the acidulant and oxidizer with Salmonella typhimurium. The sterilizing ability of E-ball treated solution was guessed due to the friction of E-ball deads. In the case of the friction of 2 beads of E-ball, Salmonella typhimurium was sterilizted on $1{\times}10^6/mL$ CFU in the E-ball treated solution. The E-ball treated solution had superior sterizing power compared with the chemical disinfectants in the bacteria of soil for antibacterial examination. E-ball treated solution has a possibility as the substitute of chemical disinfectants to protective the animal diseases contains FMD, AI.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.58 no.3
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• pp.559-565
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• 2009

In this paper, we invented a new and unique technique for the sterilization of Escherichia coli(E. coli) in polluted water. We applied a rich ultra-violet(UV) light from pulsed xenon flashlamp and photocatalyst(TiO2) to sterilize E. coli in polluted water. This method based on the use of UV light and photocatalyst is eco-friendly and does not cause secondary pollution. The proposed elliptical reactor is able to concentrate on quartz sleeve coated TiO2 or general quartz sleeve. The primary objective of our research was to determine the important parameters such as pulse repetition rate and input voltage and to know on the sterilizing efficiency of quartz sleeve coated TiO2 and general quartz sleeve. We obtained to achieve 99.999% sterilization in as little as 6 pulses at 800V in case of quartz sleeve coated Ti02, and 10 pulses at 800V in case of general quartz sleeve for 5 minutes. Although transmitted light of quartz sleeve coated TiO2 is deceased, the sterilizing efficiency is increased by 40% than general quartz sleeve. The reason of high sterilizing efficiency is that generated hydroxyl radical(OH) by photocatalyst and is able to concentrate light at a focus by using elliptical reactor.

• Food Science and Biotechnology
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• v.14 no.3
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• pp.328-333
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• 2005

Finite difference model and dynamic thermal property evaluation system were developed to estimate convection heat transfer coefficient by modeling temperature-time profile of beef cube in continuous flow sterilizing system. As input parameters of the model, specific heat and thermal conductivity values of beef frankfurter meat were independently measured from 20 to $80^{\circ}C$. Convection heat transfer coefficient was estimated by comparing simulated and measured temperature-time profiles. Actual temperature-time profiles of meat cube were measured at flow rates of 15, 30, and 45 L/min and viscosities from 0 to 15 cp, and mean values of convection heat transfer coefficients ranged from 792 to $2107\;W/m^2{\cdot}K$. Convection heat transfer coefficient increased with increase in flow rate and decreased as viscosity increased.

• Journal of environmental and Sanitary engineering
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• v.5 no.2
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• pp.81-94
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• 1990

The view of this research was to investigate the state of a sanitary management in the industrial area of Masan and Changweon cities through the nutritionists who works in the group food service facilities. The following results are as indicated . 1. The management types of group food service facilities are a direct management 89.7% , a consignned management 7.7% , an(1 a semimanagement 2.6% . 2. The survey for purulent inflammation and a possible disease of a cook is 59.0%. In the case of a wound of hand and foot and disease, the rate of non-worked people is 51.3% 3.4 regular medical examination of a cook was generally well executed, but only 64.1% were received an examination of the feces, and 88.0%, among them had one time per 6months. 4. Wearing a cap, a gown, and a private foot-wear in a kitchen of the cook was well executed, but nowhere was found to put on a mask 5. Only 11.5% of the group feeding facilities had a their own sterilizing lamp, and the company with a repository in a low temperature was 25.6% , 6.4 private toilet of the cook were estabilshed at rate of 38.5% , and also a private toilet providing with a sterilizing soap was 52.6% . 7. The pasteurization of a kitchen table before cooking was 28.2%, In the case of using a cooking dipper, spoon, tweezers when one taste was 83.3% , and using a hand when one dish up was 74.4 %. 8. When one use a raw egg, washing a shell was 35.9%. 9. The rate of a nutritionists writing a diary of the sanitary check-up was 75.6%, and only 23.1% of the facilities was provided with a preserved food. 14.1% of the nutritionists did a sanitary eaucation periodically.

• Journal of Biosystems Engineering
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• v.28 no.5
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• pp.449-456
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• 2003

A robot system was developed to pick desired colony. This robot system consisted of an image acquisition process which acquires the image information of colony, an illumination device which irradiates the object once when it gets the image of it, a picking head, a replicating head, a bed for fixing well-plates, and a sterilization device of sterilizing pin stained with colony. Picking pins were washed in an ultrasonic wave washing for takes ten seconds. Picking pins were dipped for sterilizing in alcohol for ten seconds. The time for resterilizing picking pins in a heater was five seconds. This performance test resulted 100% success rate for both the colony picking and the colony replication process. Considering the procedure in which 8 pins were smeared by colony, picked on a well plate, and sterilized as one cycle, the system could carry out one cycle in 110 seconds. It took about 138 minutes to pick around 600 colonies.

• 한국전산유체공학회:학술대회논문집
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• 2008.03b
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• pp.534-537
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• 2008

Growing attention has been given to sterilizing and antibacterial effects of nano-silver, recently. Nano-silver solution can be applied to the heat exchanger in an air conditioner to prevent bad smell or bacteria. The present study is directed at the nozzle spray characteristics over a heat exchanger. This problem is of particular interest in the design of a nano-silver HVAC system. The effects of nozzle position and flow rate on the spray area over a horizontal surface have been investigated for various nozzles. The results obtained indicate that spray area is increased as the height of spray position is increased or mass flow rate is increased. The wetted area over a practical heat exchanger is also studied at a given nozzle height. It is found that the wetted area is gradually increased with an increase in the flow rate. However, the effect of flow rate on the wetted area is a little affected by flow rate in the range of too much flow rate. It is also found that the wetted area is decreased as the inclination angle of a heat exchanger is increased.

• The Journal of Asian Finance, Economics and Business
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• v.9 no.2
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• pp.37-47
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• 2022

This study uses monthly data from January 2009 to December 2020 to examine the effectiveness of foreign currency intervention and its influence on monetary policy in Vietnam using a Hierarchical Bayesian VAR model. The findings suggest that foreign exchange intervention has little influence on the exchange rate level or exports, but it can significantly minimize exchange rate volatility. As a result, we can demonstrate that the claim that Vietnam is a currency manipulator is false. As well, the forecast error variance decomposition results reveal that interest rate differentials mainly determine the exchange rate level instead of foreign exchange intervention. Moreover, the findings suggest that foreign exchange intervention is not effectively sterilized in Vietnam. Inflation is caused by an increase in international reserves, which leads to an expansion of the money supply and a decrease in interest rates. Although the impact of foreign exchange intervention grows in tandem with the growth of international reserves, if the sterilizing capacity does not improve, rising foreign exchange intervention will instead result in inflation. Finally, we use a rolling window approach to examine the time-varying effect of foreign exchange intervention.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.42 no.2
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• pp.12-19
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• 2010

This study was carried out to explore the availability of seedling pots made from paper mill sludge using red pepper species called Nokkwang. The seedling pots were made by several conditions such as different mixing ratios between sludge and old newspaper (ONP), sterilizing treatment and latex coating. After 30 day cultivation in a green house, the growth condition of the red peppers was evaluated by comparison with those raised in the plastics seedling pots. The red peppers in the plastics pot showed a better growth than those in the sludge pots. Sterilizing treatment, latex coating and different mixing ratios between paper sludges and ONP did rarely affect a growth rate of the plant and the contents of inorganic elements. However, latex coating contributed to protection of physical structure of the sludge pots in spite of constant water feeding. Even though some inorganic elements from the sludge pots migrated into the bed soils, electronic conductivity of the bed soils was within the proper range for the plant growth. Finally it was confirmed that the seedling pots made from paper mill sludges could be used to cultivate horticultural plants as the alternative to the plastics pots.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.25 no.6
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• pp.520-528
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• 1992

In order to establish the standard conditions for thermal sterilization of foods, a microcomputer based $F_o-value$ measuring system was developed upon the basis of the time-temperature profile in food. $F_o-value$ was calculated simultaneously from the time-temperature profile, and described as integrated lethality during the whole sterilization process. The accuracy of system was evaluated by the analysis of thermal diffusivity of the model solid food, Alaska pollack surimi. The $F_o-value$ could be measured precisely under the different sterilizing conditions as the varied time and temperature. The practical thermal diffusivities from various sterilizing conditions agreed well to the values predicted by some experimental equations suggested in the literatures. The differences were within the range of $\pm12\%$.