• KSCE Journal of Civil and Environmental Engineering Research
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• v.4 no.4
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• pp.113-125
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• 1984

Water supply has been mainly dependent on the construction of the dams in Korea. It is difficult, however, to continue to construct dams for many reasons, such as the decrease of construction sites, the increase of construction costs, the compensation of residents in flooded areas, and the environmental effects. Water demands have increased and are expected to continue increasing due to the concentration of people in the cities, the rise of the living standard, and rapid industrial growth. It is acutely important to find countermeasures such as development of ground water, desalination, and recycling of waste water to cope with increasing water demands. Recycling waste water includes all means of supplying non-potable water for their respective usages with proper water quality which is not the same quality as potable water. The usages of the recycled water include toilet flushing, air conditioning, car washing, yard watering, road cleaning, park sprinkling, and fire fighting, etc. Raw water for recycling is obtained from drainage water from buildings, toilets, and cooling towers, treated waste water, polluted rivers, ground water, reinfall, etc. The water quantity must be considered as well as its quality in selecting raw water for the recycling. The types of recycling may be classified roughly into closed recycle systems and open recycle systems, which can be further subdivided into individual recycle systems, regional recycle systems and large scale recycle system. The treatment methods of wastewater combine biochemical and physiochemical methods. The former includes activated sludge treatment, bio-disc treatment, and contact aeration treatment, and the latter contains sedimentation, sand filtration, activated carbon adsorption, ozone treatment, chlorination, and membrane filter. The recycling patterns in other countries were investigated and the effects of the recycling were divided into direct and indirect effects. The problems of water reuse in recycle patterns were also studied. The problems include technological, sanitary, and operational problems as well as cost and legislative ones. The duties of installation and administrative organization, structural standards for reuse of water, maintenance and financial disposal were also studied.

• Journal of the Korea Organic Resources Recycling Association
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• v.25 no.1
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• pp.103-110
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• 2017

In Concentrated Animal Feeding Operations(CAFOs), emission of ammonia from stored manure contributes negatively on the wellness of livestock. In CAFOs facilities, indoor aerial ammonia concentration oftentime surpasses the critical level potentially harmful to livestock's immune system. Understandably, numerous researches to control aerial ammonia have been conducted in countries where CAFOs were practiced for many decades. Some innovative technologies, such as scrubber, bio-filter, and additives emerged, as a result. Among them, microbial additives became popular in Korea, due to an easiness of use and affordability. However, microbial additives still have some weaknesses. Their price is still high enough to discourage farmers who run a small scale farm and their effectiveness are still questioned by many users and researchers. In the present study, we found soluble carbohydrates, such as sugar, glucose, and molasses, when supplemented to pig slurry manure, can mitigate ammonia emission. To be more specific, pig manure slurry(120kg), stored in container(200L), was supplemented with sugar at 0.1%(w/w) and was, subsequently, monitored for pH and aerial ammonia for next 10 days. From this experiment, it was found that the sugar supplementation was effective in mitigating the aerial ammonia concentration (33% in average) when monitored daily. Also, the pH of manure slurry was maintained at relatively low level(8.2) in sugar-supplemented manure slurry while it was elevated to 8.5 in untreated slurry. Conclusively, the obtained data suggest that soluble carbohydrate can mitigate ammonia emission by acidifying manure slurry. Additionally, it can be suggested that soluble carbohydrates, such as sugar, glucose, and molasses, can be reasonable choices for animal farmers who have been looking for an alternative choice to replace expensive microbial additives.

• Journal of the Korean Institute of Landscape Architecture
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• v.46 no.2
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• pp.62-68
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• 2018

This study investigated the effect of light intensity on the removal of particulate matter by Dieffenbachia amoena 'Marianne' and Spathiphyllum spp.. An acrylic chamber ($600{\times}800{\times}1200mm$, $L{\times}W{\times}H$) modeled as an indoor space and a green bio-filter ($495{\times}495{\times}1000mm$, $L{\times}W{\times}H$) as an air purification device were made of acrylic. The removal of particulate matter PM10 and PM1, the photosynthetic rate, stomatal conductance, and number of stomata of Dieffenbachia amoena 'Marianne' and Spathiphyllum spp. were measured according to three different levels of light intensity (0, 30 and $60{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}PPFD$). Regarding the length of time taken for PM10 to reach $1{\mu}g$, the Dieffenbachia amoena 'Marianne' showed a significant difference according to the presence or absence of light, and there was no significant difference shown between light intensity of 30 and $60{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}PPFD$. As for the Spathiphyllum spp., there was no significant difference between 0 and $30{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}PPFD$, while a significant difference was shown at $60{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}PPFD$. After 90 minutes, the PM1, PM10, and $CO_2$ residuals of the Spathiphyllum spp. were lowest at $60{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}PPFD$. The remaining amount of PM1 and PM10 was lower with the Spathiphyllum spp. than with the Dieffenbachia amoena 'Marianne', even at $0{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}PPFD$. With both plants, the higher the light intensity, the higher the photosynthetic rate, while the stomatal conductance did not show any significant difference. Spathiphyllum spp. showed a higher photosynthetic rate and stomatal conductance and a greater number of stomata than Dieffenbachia amoena 'Marianne', and stomata were observed in both the front and back sides of the leaves. The air purification effect of Spathiphyllum spp. is considered to be better than Dieffenbachia amoena 'Marianne' at the same light intensity due to such plant characteristics. Therefore, in order to select effective indoor plants for the removal of particulate contamination in an indoor space, the characteristics of plants such as the photosynthetic rate and the number and arrangement of stomata according to indoor light intensity should be considered.

• Journal of Korean Society of Forest Science
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• v.109 no.1
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• pp.41-49
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• 2020

In this study, the effect of seed pre-treatments and pellet coating materials to enhance the efficiency of large-scale propagation of Aster koraiensis seeds were investigated. Seeds were immersed in water for one day, and only those that sank were used for pre-treatment to use filled seeds. Pre-treatments were divided into hormone treatments, with gibberellic acid (GA₃; 200 and 500 ppm) and 24-epibrassinolide (10^-6, 10^-7, and 10^-8M), and priming with potassium nitrate (100 mM of KNO₃). To produce pellet-coated seeds, pellet materials (DTCS or DTK) were applied to control (unprimed) and primed seeds with binders (PVA or CMC). The maximum germination percent (GP) of seeds before pellet coating was 65% (with the priming treatment), and there was no difference in the GP of seeds among hormone treatments. For seeds sown in a growth chamber on filter paper, GP was 41% for control (unprimed/uncoated) seeds, 65% for uncoated primed seeds, 71% for DTCS/PVA-pellet-coated seeds, and 42% for DTK/CMC-pellet-coated seeds. Seeds that were primed first and then pellet-coated showed greatly improved GP, mean germination time (MGT), and germination rate than seeds that were only pellet-coated. For seeds sown in commercial soil in a greenhouse, control seeds had a GP of 27%, whereas primed seeds had the highest GP (58%), and their MGT and GT were 9.4 days and 7.0%·day, respectively. In addition, DTK/PVA-pellet-coated seeds (40%) also had a GP higher than the control (27%), and their MGT was 15-27 days. For seeds sown in sandy-loam soil in a greenhouse, unprimed-pellet-coated seeds and primed-pellet-coated seeds both had GPs ranged of 39%, which were lower than that of control seeds. In general, the seeds that were pellet-coated with DTK had a higher GP than those pellet-coated with DTCS. Furthermore, the MGT of unprimed-pellet-coated seeds was 15.0-19.8 days, which was longer than the MGT of primed-pellet-coated seeds. These results suggest that priming enhances seedling emergence of Aster koraiensis seeds. Moreover, when priming is combined with pellet coating, DTK is a more suitable pellet material than DTCS, and PVA and CMC are equally suitable adhesives.

• The Korean Journal of Nuclear Medicine Technology
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• v.14 no.1
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• pp.122-126
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• 2010

Purpose: F-18-FPCIT that shows strong familiarity with DAT located at a neural terminal site offers diagnostic information about DAT density state in the region of the striatum especially Parkinson's disease. In this study, we altered the iteration and subset and measured SUV${\pm}$SD and Contrasts from phantom images which set up to specific iteration and subset. So, we are going to suggest the appropriate range of the iteration and subset. Materials and Methods: This study has been performed with 10 normal volunteers who don't have any history of Parkinson's disease or cerebral disease and Flangeless Esser PET Phantom from Data Spectrum Corporation. $5.3{\pm}0.2$ mCi of F-18-FPCIT was injected to the normal group and PET Phantom was assembled by ACR PET Phantom Instructions and it's actual ratio between hot spheres and background was 2.35 to 1. Brain and Phantom images were acquired after 3 hours from the time of the injection and images were acquired for ten minutes. Basically, SIEMENS Bio graph 40 True-point was used and True-X method was applied for image reconstruction method. The iteration and Subset were set to 2 iterations, 8 subsets, 3 iterations, 16 subsets, 6 iterations, 16 subsets, 8 iterations, 16 subsets and 8 iterations, 21 subsets respectively. To measure SUVs on the brain images, ROIs were drawn on the right Putamen. Also, Coefficient of variance (CV) was calculated to indicate the uniformity at each iteration and subset combinations. On the phantom study, we measured the actual ratio between hot spheres and back ground at each combinations. Same size's ROIs were drawn on the same slide and location. Results: Mean SUVs were 10.60, 12.83, 13.87, 13.98 and 13.5 at each combination. The range of fluctuation by sets were 22.36%, 10.34%, 1.1%, and 4.8% respectively. The range of fluctuation of mean SUV was lowest between 6 iterations 16 subsets and 8 iterations 16 subsets. CV showed 9.07%, 11.46%, 13.56%, 14.91% and 19.47% respectively. This means that the numerical value of the iteration and subset gets higher the image's uniformity gets worse. The range of fluctuation of CV by sets were 2.39, 2.1, 1.35, and 4.56. The range of fluctuation of uniformity was lowest between 6 iterations, 16 subsets and 8 iterations, 16 subsets. In the contrast test, it showed 1.92:1, 2.12:1, 2.10:1, 2.13:1 and 2.11:1 at each iteration and subset combinations. A Setting of 8 iterations and 16 subsets reappeared most close ratio between hot spheres and background. Conclusion: Findings on this study, SUVs and uniformity might be calculated differently caused by variable reconstruction parameters like filter or FWHM. Mean SUV and uniformity showed the lowest range of fluctuation at 6 iterations 16 subsets and 8 iterations 16 subsets. Also, 8 iterations 16 subsets showed the nearest hot sphere to background ratio compared with others. But it can not be concluded that only 6 iterations 16 subsets and 8 iterations 16 subsets can make right images for the clinical diagnosis. There might be more factors that can make better images. For more exact clinical diagnosis through the quantitative analysis of DAT density in the region of striatum we need to secure healthy people's quantitative values.

• Journal of Food Hygiene and Safety
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• v.28 no.4
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• pp.349-353
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• 2013

This study was performed to evaluate the bactericidal efficacy of Fumagari OPP$^{(R)}$, fumigation disinfectant, containing 20% ortho-phenylphenol against Staphylococcus aureus (S. aureus). In this research, efficacy test of fumigant against S. aureus was carried out according to French standard NF T 72-281. S. aureus working culture suspension number (N value), all of the colony numbers on the carriers exposed with the fumigant (n1, n2, and n3), the number of bacterial test suspentions by pour plate method (N1), the number of bacterial test suspentions by filter membrane method (N2) and the mean number of bacteria recovered on the control-carriers (T value) were obtained from the preliminary test. In addition, the reduction number of S. aureus exposed with the fumigant (d value) was calculated using T value, the mean number of bacteria in recovery solution (n'1) and the mean number of bacteria on carriers plated in agar (n'2). N value was $4.0{\times}10^8$ CFU/mL, and n1, n2, and n3 were higher than 0.5N1, 0.5N2 and 0.5N1, respectively. Additionally, T value was $3.4{\times}10^6$ CFU/mL. In the bactericidal effect of the fumigant, the d value was 6.43 logCFU/mL. According to the French standard for the fumigant, the d value for the effective bactericidal fumigant should be over than 5 logCFU/mL. The results indicated that Fumagari OPP$^{(R)}$ had an effective bactericidal activity against S. aureus, then the fumigant can be applied to disinfect food materials and kitchen appliances contaminated with pathogenic bacteria.

• Journal of Food Hygiene and Safety
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• v.29 no.1
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• pp.60-66
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• 2014

This test was performed to evaluate the bactericidal efficacy of a fumigation disinfectant containing 20% ortho-phenylphenol against Pseudomonas aeruginosa (P. aeruginosa) and Enterococcus hirae (E. hirae). In preliminary tests, P. aeruginosa and E. hirae working culture suspension number (N value) were $2.8{\times}10^8$ and $4.0{\times}10^8CFU/mL$, respectively. And all the colony numbers on the carriers exposed to the fumigant (n1, n2, n3) were higher than 0.5N1 (the number of bacterial test suspentions by pour plate method), 0.5N2 (the number of bacterial test suspentions by filter membrane method) and 0.5N1, respectively. In addition, the mean number of P. aeruginosa and E. hirae recovered on the control-carriers (T value) was $2.8{\times}10^8$ and $3.4{\times}10^6CFU/mL$, respectively. In the bactericidal effect of the fumigant, the reduction number of $2.8{\times}10^8$ (d value) was 6.46 and 5.19 logCFU/mL, respectively. According to the French standard for the fumigant, the d value for the effective bactericidal fumigant should be over than 5 logCFU/mL. With the results from this study, the fumigation disinfectant containing 20% ortho-phenylphenol has an effective bactericidal activity, then the fumigant can be applied to disinfect food materials and kitchen appliances contaminated with the pathogenic bacteria.

• Korean Journal of Environmental Agriculture
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• v.37 no.4
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• pp.302-311
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• 2018

BACKGROUND: Dithianon (75%) formulation were mixed and sprayed as closely as possible by normal practice on the ten farms located in the Mungeong of South Korea. Patches, cotton gloves, socks, masks, and XAD-2 resin were used for measurement of the potential exposure of dithianon on the applicators wearing standardized whole-body outer and inner dosimeter (WBD). This study has been carried out to determine the dermal and inhalation exposure to dithianon during preparation of spray suspension and application with a power sprayer on a apple orchard. METHODS AND RESULTS: A personal air monitor equipped with an air pump, IOM sampler and cassette, and glass fiber filter was used for inhalation exposure. The field studies were carried out in a apple orchard. The temperature and relative humidity were monitored with a thermometer and a hygrometer. Wind speed was measured using a pocket weather meter. All mean field fortification recoveries were between 85.1% and 99.1% in the level of 100 LOQ (limit of quantification), while the LOQ for dithianon was $0.05{\mu}g/mL$ using HPLC-DAD. The exposure to dithianon on arms of the mixer/loader (0.0794 mg) was higher than other body parts (head, hands, upper body, or legs). The exposure to dithianon on the applicator's legs (3.78 mg) was highest in the body parts. The dermal exposures for mixer/loader and applicator were 10 and 8.10 mg, respectively, from a grape orchard. The inhalation exposure during application was estimated as 0.151 mg, and the ratio of inhalation exposure was 11.2% of the dermal exposure (inner clothes). CONCLUSION: The dermal and inhalation exposure on the applicator appeared to be 4.203 mg - 25.064 mg and $0.529{\mu}g-116.241{\mu}g$, respectively. The total exposures on the agricultural applicators were at the level of 2.596 mg - 25.069 mg to dithianon during treatment for apple orchard. The TER showed 3.421 (>1) when AOEL of dithianon was used as a reference dose for the purpose of risk assessment of the mixing/loading and application.