• Journal of Microbiology and Biotechnology
• /
• v.12 no.4
• /
• pp.583-591
• /
• 2002

Biodegradation of fat, oil, and grease (FOGs) plays an Important role in wastewater management and water pollution control. However, many industrial food-processing and food restaurants generate FOG-containing waste waters for which there Is no acceptable technology for their pretreatment. To solve these problems, this study evaluated the feasibility of effective FOG-degrading microorganisms on the biodegradation of olive oil and FOG-containing wastewater. Twenty-two strains capable of degrading FOGs were isolated from five FOG-contaminated sites for the evaluation of their FOG degradation capabilities. Among twenty-two strains tested, the lipase-producing Pseudomonas sp. strain D2D3 was selected for actual FOG wastewater treatment. Its biodegradability was performed at 3$0^{\circ}C$ and pH 8. The extent of FOG removal efficiency was varied for each FOG tested, being the highest for olive oil and animal fat (94.5% and 94.4%), and the lowest for safflower oil (62%). The addition of organic nitrogen sources such as yeast extract, soytone, and peptone enhanced the removal efficiency of FOGs, but the addition of the inorganic nitrogen nutrients such as $NH_4$Cl and $(NH_4)_2SO_4$ did not increase. The $KH_2PO_4$ sources in 0.25% to 0.5% concentrations showed more than 90% degradability. As a result, the main pathway for the oxidation of fatty acids results in the removal of two carbon atoms as acetyl-CoA with each reaction sequence: $\beta$-oxidation. Its lipase activity showed 38.5 U/g DCW using the optimal media after 9 h. Real wastewater and FOGs were used for determining the removal efficiency by using Pseudomonas sp. strain D2D3 bioadditive. The degradation by Pseudomonas sp. strain D2D3 was 41% higher than that of the naturally occurring bacteria. This result indicated that the use of isolated Pseudomonas sp. strain D2D3 in a bioaugmentating grease trap or other processes might possibly be sufficient to acclimate biological processes for degrading FOGs.

• Journal of Bio-Environment Control
• /
• v.20 no.1
• /
• pp.1-7
• /
• 2011

The objective of the present study is to identify the applicability of a low pressure fogging system for cooling commercial tomato greenhouse. In particular, the cooling system in this experiment utilizes low pressure spray nozzles which were developed in Korea recently. The experimental result that the temperature in fog-cooled greenhouse was lower than the non-cooled greenhouse showed the cooling effect by the low pressure fogging system. But because the relative humidity in fog-cooled greenhouse was comparatively low, the satisfactory cooling effect could be acquired by narrowing the space of fog nozzles and extending fogging time to supply more fog spray quantity. The variation of temperature distribution in fog-cooled greenhouse along timelag was insignificant during short time, but that was great during long period of day. This result showed the variation of temperature along timelag was slight by fog cooling but great by other factors like radiation, ventilation, air flow, etc. The advanced operation technology of fog system was required to reduce the variation of temperature along time lag. We plan to suggest the advanced installation and operation technology of low pressure fogging system for cooling commercial tomato greenhouse by further experiments in near future.

• Journal of Bio-Environment Control
• /
• v.24 no.3
• /
• pp.258-263
• /
• 2015

This study was conducted to evaluate the effects of the fog-cooling system on the growth and yield characteristics of two large-fruited paprika cultivars during summer cultivation season. The temperature inside the greenhouse equipped with fog-cooling system was $2-3^{\circ}C$ lower than that in the control. The results of study show the possibilities of maintaining indoor temperatures below $35^{\circ}C$ and relative humidity at the level of 80% using fogcooling system during hot seasons of the year. Plant height, fruit weight and number of fruits per plant were higher for both cultivars in the fog-cooling treatment compared to those in control. Mean fruit weight and yield per unit area were higher in the fog-cooling treatment than those in the control. However there were no significant differences in sugar content, flesh thickness and locule number of fruits due to fog-cooling system. Number of fruits with epidermal cracking was decreased in the fog-cooling system for both paprika cultivars. Mineral contents of plants such as nitrogen (N), potassium (K), calcium (Ca), magnesium (Mg), were not affected due to fog-cooling treatment.

• Journal of Conservation Science
• /
• v.32 no.4
• /
• pp.491-500
• /
• 2016

Fog is atmospheric in which tiny drops of water vapor are suspended in the air near the ground. Its form, occurrence, etc., change according to the temperature, relative humidity, wind and geographical features of the space around it. In particular, fog tends to occur near a source of water because of temperature and relative humidity difference. These days, climate change is increasingly affecting the occurrence of fog. Therefore the purpose of this study was to investigate how fog affects materials that are part of our cultural properties through outdoor exposure tests and artificial degradation. The degradation evaluation of materials as a function of fog occurrence frequency, showed that the color of metals changed noticeably, whereas dyed silk and Dancheong showed degradation on the surface and color differences but no particular tendencies. Therefore, damage prediction by color differences as a function of fog occurrence frequency was based on metal samples, which showed constant color differences. Through a comparison of the predictive value and color difference by outdoor exposure, the accuracy and applicability of the damage prediction formula was confirmed. If a more complex damage prediction formula is created, it is expected that prediction of the degree of material damage in the field would be possible.

• Korean Journal of Breeding Science
• /
• v.40 no.2
• /
• pp.159-163
• /
• 2008

A New spary chrysanthemum (Dendranthema grandiflorum) cultivar 'Water Fog' was bred by open pollination of 'Angaesoguk'. Its characteristics were investigated three times from 2004 to 2006 under forcing culture in spring and retarding culture in autumn. The natural flowering time of 'Water Fog' was 24 October, but year-round production was possible by shading and lighting. It had flower diameter of 2.3 cm, 46.5 petals and 34.4 flowers per stem in autumn. The petal was narrow(0.4cm) and the color of petal was white with presence of green at flower center. Days to flower from short-day start for 'Water Fog' was about 48 in spring. 'Water Fog' showed the vase life of 22.6 days in autumn. This cultivar was registered for a commercialization in 2007. 'Water Fog' would be cultured under greenhouse and rain shelter condition in Korea.

• The Journal of The Korea Institute of Intelligent Transport Systems
• /
• v.21 no.2
• /
• pp.101-115
• /
• 2022

This study compared the performance of LiDAR in detecting objects in rough weather with that in clear weather. An experiment that reproduced rough weather divided the fog visibility into four stages from 200 m to 50 m and controlled the rainfall by dividing it into 20 mm/h and 50 mm/h. The number of points cloud and intensity were used as the performance indicators. The difference in performance was statistically investigated by a T-Test. The result of the study indicates that the performance of LiDAR decreased in the order in situations of 20 mm/h rainfall, fog visibility less than 200 m, 50 mm/h rainfall, fog visibility less than 150 m, fog visibility less than 100 m, and fog visibility less than 50 m. The decreased performance was greater when the measurement distance was greater and when the color was black rather than white. However, in the case of white, there was no difference in performance at a measurement distance of 10 m even at 50 m fog visibility, which is considered the worst situation in this experiment. This no difference in performance was also statistically significant. These performance verification results are expected to be utilized in the manufacture of road facilities in the future that improve the visibility of sensors.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2012.05a
• /
• pp.1187-1188
• /
• 2012

• Journal of Bio-Environment Control
• /
• v.14 no.1
• /
• pp.29-37
• /
• 2005

In order to provide fundamental data on utilization of dehumidifier in greenhouses, a condensing type dehumidifier using ground water as a coolant was developed and tested dehumidification performance. The developed dehumidifier was applied to greenhouse with fog cooling system and effect of dehumidification on improvement of evaporative cooling efficiency was analyzed. Results of the dehumidifier performance test showed that dehumidification using ground water as a coolant was sufficiently possible in fog cooling greenhouse. When the set point temperature of greenhouse cooling was $32^{\circ}C$ and as temperatures of ground water rose from $15^{\circ}C\;to\;18^{\circ}C,\;21^{\circ}C\;and\;24^{\circ}C$, dehumidification rates decreased by $17.7\%,\;35.4\%\;and\;52.8\%$, respectively. As flow rates of ground water reduced to $75\%\;and\;50\%$, dehumidification rates decreased by $12.1\%\;and\;30.5\%$, respectively. Cooling efficiency of greenhouse equipped with fog system was distinctly improved by artificial dehumidification. When the ventilation rate was 0.7 air exchanges per minute, dehumidification rates of the fog cooling greenhouse caused by natural ventilation were 53.9%-74.4% and they rose up to 75.4%-95.9% by operating the dehumidifier. In case of using the ground water of $18^{\circ}C$ and flow rate of design condition, it was analyzed that whole fog spraying water can be dehumidified even if the ventilation rate is 0.36 exchanges per minute. As a utilization of dehumidifier, it is possible to improve cooling efficiency of fog system in naturally ventilated greenhouses.

• Journal of Bio-Environment Control
• /
• v.3 no.1
• /
• pp.58-65
• /
• 1994

It is necessary to effective temperature and humidity management for normal growth of crops in protected cultivation during the summer season. Because the highest temperature of vinyl house inhibit normal growth of crop and decrease of crop production or marketability in summer season. Finally, the vinyl house was impossible some crop cultivation in summer season. This study was conducted to investigate effective and economic method for temperature drop in protected cultivation during the summer season. 1. In medium size vinyl house(5$\times$13$\times$3m), the effect of temperature drop appeared the highest in treatment of shading with aluminium thermal curtain＋fog system＋ventilation with fan. The effect of temperature drop was about 1$0^{\circ}C$ lower than outer air temperature and about 4$^{\circ}C$ lower than outer soil temperature. 2. The effect of temperature drop according to shading with aluminium thermal curtain＋fog system＋ventilation with fan during the highest temperature of summer season Jul., 20 to Aug., 21 was appeared about 8$^{\circ}C$ lower than outdoor above ground(1.2m) and about 7$^{\circ}C$ lower than outdoor surface ground. 3. The changes of solar radiation during a day according to shading with aluminium thermal curtain＋ventilation with fan and shading with black curtain＋ventilation with fan treatments was appeared respectively about 29.3%, 32.5% of outdoor solar radiation a fine day and respectively about 27.4%, 31.8% of outdoor solar radiation a cloudy day.

• Journal of Bio-Environment Control
• /
• v.6 no.1
• /
• pp.48-54
• /
• 1997

Among the various vegetables eggplant and gourd family can stand against high temperature environmental condition, about 35$^{\circ}C$. However, most of greenhouse farmers are giving up crop cultivation during hot summer season due to extreme temperature, 4$0^{\circ}C$ or above, condition of greenhouse interior. To improve this inferior crop growth condition, for nozzle system was installed in the pet greenhouse and the effect of fog system was investigated in order to determine fog water amount and the required fog nozzle numbers according to house volumes. MEE fog nozzle was selected for this Investigation which can produce water particle size of 27${\mu}{\textrm}{m}$ with water amount of 100$m\ell$ at pumping pressure of 70kg/$\textrm{cm}^2$. House cooling test was conducted in the pet greenhouse with one minute fogging and one minute air ventilation without stopping. It maintained 32$^{\circ}C$ at the house interior when the atmosphere and the house temperature were 35 and 4$0^{\circ}C$, respectively. And, an experimental equation was developed through calculating the changes of relative humidity and temperature with psychrometric equation which revealed the moisture transfer pattern between the house air and fog system. It showed that the required water fogging amounts to reduce 1$0^{\circ}C$, 40 to 3$0^{\circ}C$, needs 80.7$\ell$ for 1-2W(8,350㎥) and 99.9$\ell$ for 3-2G-3S(10,330㎥) type greenhouse with particle size of 27${\mu}{\textrm}{m}$.