• Journal of Animal Environmental Science
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• v.10 no.1
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• pp.1-10
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• 2004

A field-scale(8.6${\times}$2.5${\times}$2.4 m) and pilot-scale(1.39${\times}$0.89${\times}$0.89 m) thermophilic aerobic oxidation (TAO) units were installed to investigate the volume reduction efficiency of slurry, by varying the aeration and treatment temperature of swine manure, and the collected liquid was evaluated as a liquid fertilizer. In the field-scale unit, the aeration level and numbers of foam breakers made different effects on the slurry volume and temperature in the TAO system. The experiments were peformed for three cases, using different levels of aeration and numbers of foam breakers: Treat-A (aeration rate; 120 ㎥ air/hr using 2 air pumps and 2 foam breakers), Treat-B (aeration rate; 180 ㎥ air/hr using 3 air pumps and 3 foam breakers) and Treat-C (aeration rate; 180 ㎥ air/hr using 3 air pumps and 4 foam breakers). With the same input volume (5 ㎥/day) of swine manure slurry, the resulting liquid levels, temperatures and evaporation rates were 50∼100 cm, 31∼$64^{\circ}C$ and 55 $\ell/m^2$/day for Treat-A; 40∼90 cm, 29∼$52^{\circ}C$ and 75 $\ell/m^2$/day for Treat-B; and 40∼70 cm, 45∼$54^{\circ}C$ and 120.0 $\ell/m^2$/day for Treat-C. In the pilot-scale unit, semi-continuous flow of swine manure slurry was introduced. 50 $\ell$ every 2hr(T-1), 50 $\ell$ every 3hr(T-2), 40 $\ell$ every 2hr (T-3) and 60 $\ell$ every 4hr (T-4) within 24 hours, in order to find the maximum slurry volume reduction conditions.

• Journal of Animal Environmental Science
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• v.15 no.3
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• pp.217-224
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• 2009

The pig slurry is one of important fertilizer source for production of crops in recent years, but it has many controversial points of utilization such as offensive odor, lack of spread equipment and farmland possession, respectively. This study was carried out in order to remove water pollutants and malodor of pig slurry using biofiltration system. The biofiltration system consists of pig slurry separator, mixing shift and attached blade for sawdust or ricehull, air injection nozzle and outlet for pig slurry and sawdust or ricehull. The characteristics pH, $BOD_5$ (Biochemical Oxygen Demand), $COD_{Mn}$ (Chemical Oxygen Demand), SS (Suspended Solid), T-N (Total Nitrogen), T-P (Total Phosphorus) of the untreated pig slurry used in this study were 7.2, 34,450, 24,604, 71,000, 4,194, $1,631\;ml/{\ell}$, respectively. The $NH_3$ (Ammonia) and $H_2S$(Hydrogen Sulfide) concentration were 70.0, 9.6 ppm, respectively. The initial total microorganisms of pig slurry were $5.0{\times}10^3\;cfu/ml$, and Salmonella, Bacillus were $5.8{\times}10^2$, $1.1{\times}10^3\;cfu/ml$, respectively. The filtration system was very effective on removal of water pollutants of pig slurry. The removal efficiency of the offensive odor of ammonia and hydrogen sulfide in sawdust was higher than those of ricehull. The total microorganisms and bacillus of pig slurry are on the increase by sawdust and ricehull, but Salmonella showed a tendency to decrease in number after that time. Accordingly, the filtration system was very effective to produce a good quality pig slurry.

• Research in Plant Disease
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• v.16 no.1
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• pp.101-105
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• 2010

This study was aimed to understand conidial disperse of the pepper anthracnose fungus Colletotrichum acutatum, elapse time for the disease development, and inoculum potentials on infected fruits. Most (99.2%) conidia of the fungus disseminated from inoculum source on the rainy day, while only 0.8% conidia dispersed on the sunny day. Among the conidia 93.3% were caught under 60 cm height at 30 cm distance; however, conidia were detected at 120 cm height at the distance. Relatively susceptible pepper fruits to anthracnose showed first visible symptoms at 4 days after infection under a mimic field condition. However, it seemed that over 10 days are required for the disease to develop on moderately resistant pepper fruits under unfavorable conditions. The number of conidia formed on a lesion was positively correlated with the lesion size ($R^{2}=0.88$). Over 10 millions of conidia were formed at a normal lesion size 1.5 cm in length. In some large coalesced lesions ca. 4cm in length produced over 100 millions of the fungal conidia. Results further confirmed that the rainfall is the key factor for the inoculum disperse of the pepper anthracnose pathogen, Colletotrichum acutatum, and a long distance dissemination is plausible according to rain and wind intensity. Consequently, rain-proof structures are ideal to avoid the disease, and removal of infected fruits and timely chemical spray are indispensible to reduce the inoculum potential in the field.

• Journal of Korea Soil Environment Society
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• v.1 no.2
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• pp.23-34
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• 1996

The biological magnification of Pb, Cu, Zn and Fe in vascular plant, Persicaria thunbergii, Trapa japonica and Nymphoides peltata natually grown at the river and riverside and relationship between the concentration of heavy metals in these vascular plants and in the soil were investigated in the Chonju river, Chonju city. The biological magnification values of these metals in P thunbergii were founded as follows ; Pb, Cu, Zn and Fe were 80.4~254.6$mu\textrm{g}$/g, 284.6~688.4$mu\textrm{g}$/g, 635.5~1979.4$mu\textrm{g}$/g and 1160.0~3590.9$mu\textrm{g}$/g respectively. In the case of T. japonica, Pb, Cu, Zn and Fe were 107.8~306.0$mu\textrm{g}$/g, 282.7~963.0p$mu\textrm{g}$/g, 1328.3~3546.$mu\textrm{g}$/g and 656.8~9944.0$mu\textrm{g}$/g and in N. peltata, 140.1~ 193.9$mu\textrm{g}$/g, 187.7~327.3$mu\textrm{g}$/g, 1126.6~1723.6$mu\textrm{g}$/g and 611.7~1914.6$mu\textrm{g}$/g respectively. The amount of the biological magnification of heavy metals in the leaf, stem and root of these plants was generally increased in the sequence of leaf

• Journal of Korea Soil Environment Society
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• v.2 no.2
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• pp.9-24
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• 1997

Surfactant-aided in situ soil flushing has been proposed as an alternative for the expensive and time consuming 'pump and treat' technology in remediation of contaminated soil and groundwater Injected surfactants can effectively solubilize contaminants sorbed to the soil matrix or nonaqueous phase liquids(NAPLs) in residual saturation. The contaminants solubilized in groundwater are recovered and treated further. The theoretical background of the technology and the results of the field operations, mostly in the US. were summarized. In addition, the factors crucial to the successful application of the technology were discussed. Cost analyses and technical limitations in current applications were also discussed. In conclusion, it is likely that in situ surfactant flushing become a viable option for soil remediation in limited cases. Currently, further advances with respect to operation cost and to treatment efficiency are required for more extensive application of the technology. However, the current trends in soil remediation, specially the growing emphasis on risk based corrective action and natural attenuation, will increase the competitiveness of the technology. For example, removal of easily washable contaminants by short term soil flushing followed by long term monitoring and natural attenuation can greatly reduce the operation cost and time.

• Journal of Food Hygiene and Safety
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• v.31 no.3
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• pp.153-166
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• 2016

The purpose of this study was to investigate consumers' perceptions on monosodium L-glutamate (MSG) in social media. Data were collected from Naver blogs and Naver web communities (Korean representative portal web-site), and media reports including comment sections on a Yonhap news website (Korean largest news agency). The results from Naver blogs and Naver web communities showed that it was primarily mentioned MSG-use restaurant reviews, 'MSG-no added' products, its safety, and methods of reducing MSG in food. When TV shows on current affairs, newspaper, or TV news reported uses and side effects of MSG, search volume for MSG has increased in both PC and mobile search engines. Search volume has increased especially when TV shows on current affairs reported it. There are more periods with increased search volume for Mobile than PC. Also, it was mainly commented about safety of MSG, criticism of low-quality foods, abuse of MSG, and distrust of government below the news on the Yonhap news site. The label of MSG-no added products in market emphasized "MSG-free" even though it is allocated as an acceptable daily intake (ADI) not-specified by the Joint FAO/WHO Expert Committee on Food Additives (JECFA). When consumers search for MSG (monosodium L-glutamate) or purchase food on market, they might perceive that 'MSG-no added' products are better. Competent authorities, offices of education and local government provide guidelines based on no added MSG principle and these policies might affect consumers' perceptions. TV program or news program could be a powerful and effective consumer communication channel about MSG through Mobile rather than PC. Therefore media including TV should report item on monosodium L-glutamate with responsibility and information based on scientific background for consumers to get reliable information.

• Korean journal of food and cookery science
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• v.25 no.3
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• pp.365-378
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• 2009

This study performed microbiological hazards analysis in raw food materials, cooking processes, kitchen staff, utensils, and the environment in order to obtain contamination levels of S. aureus in school foodservice operations. S. aureus was not detected in cooked foods offered by the foodservice operations; however, it was found in raw food materials prior to cooking. In the case of vegetables, S. aureus was detected in washed mung bean sprouts, parboiled mung bean sprouts, and bellflower roots both before and after disinfection, at levels of 2.2, 1.0, 1.0, and 1.0 log CFU/g, respectively. For processed foods, S. aureus was detected in one sample of packaged bean curd as well as in mung bean jelly cake at the level of 1.5 log CFU/g. For meat products, S. aureus was detected in beef brisket and chicken at levels of 2.3 and 1.3 log CFU/g, respectively. To determine microbiological hazard data for the hands and gloves of cooking personnel, the staff members were divided into two groups: a group presenting Enterobacteriaceae or coliforms, and another group presenting neither Enterobacteriaceae nor coliforms. The results showed that S. aureus was detected on the hands of staff in each group at levels of 2.0 and 2.1 log CFU/hand, respectively, and at 1.8 and 0.0 log CFU/hand on the gloves of staff in each group, respectively. Among kitchen utensils, as an environmental factor in school foodservice operations, S. aureus was detected on meat knives, mixing bowls, and dish cloths at levels exceeding 1.0 log CFU/hand.

• Journal of the Korean Geographical Society
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• v.38 no.4
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• pp.630-639
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• 2003

This study aims to analysis the distribution and change of cropland and forest, the Onseong, Saebyeol, and Eundeok counties on the lower reach of Duman(Tumen) river, northeast Korea, using 1992 year Landsat TM data, 2000 year Landsat ETM data, and digital terrain elevation data(DTED). Land cover and land use of the study areas are classified into cropland, forest, village, and water body, using the supervised classification method including 1:50,000 DTED analysis, image band composition, and principal component analysis(PCA). Results of quantitative analysis present that each growth rate of cropland of Onseong and Eundeok are 22.8% and 14.7% corresponding to decreasing rates of forest, 8% and 13.6% during 8 years from 1992 to 2000. In Onseong, Saebyeol, and Eundeok, each values of mean elevations and slope gradients increased to 192m, 95m, and 91m from 157m, 85m, and 78m, and to 6.6$^{\circ}$, 3.0$^{\circ}$, and 4.4$^{\circ}$ from 5.2$^{\circ}$, 2.5$^{\circ}$, and 3.0$^{\circ}$. Especially, in case of newly developed cropland, the values of mean elevation and mean gradient have 225m, 122m, and 127m, and 9.4$^{\circ}$, 5.1$^{\circ}$, and 8.0$^{\circ}$, in above three regions. These new croplands were developing along to deeper valleys and toward lower hill and mountain slope up to knickpoint zone of gradient change. Deforested lands for cropland have formed irregular pattern of patch-type, and become sources for the sheet erosion, rilling and gulleying in mountain slope and sedimentation in local river channel. Though there were no field checking, analysis using landsat images and GIS mapping can help understand actual environmental problems relating to cropland development of mountain slope in North Korea.

• Journal of Bio-Environment Control
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• v.29 no.4
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• pp.337-343
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• 2020

This study was carried out to evaluate the yield of cuttings according to the planting and runner releasing times of mother plants in order to raise the cutting seedlings of raising seedling period 75 days or more needed for forcing culture of strawberries to be transplanted into the field around the 15^th of September. Three domestic cultivars of 'Maehyang', 'Jukhyang', and 'Kuemsil' were tested. For experiment 1 to determine the yield of cuttings with the change of transplanting time, the mother plant were planted on February 28, March 20, and April 9 in 20 days intervals, and the cuttings were collected two to three times from June 4 to July 1. Experiment 2 was conducted to investigate the yield of cuttings depending on the runner releasing time, the runners were released in three intervals of 20 days, 40 days, and 60 days after planting the mother plant on March 5, and the cutting were collected once to three times from May 29 to June 26. From the comparisons of cutting yield according to the transplanting time of mother plants, February 28 treatment was more 9~25% and 114~165% for each cultivar than March 20 and April 9, respectively (Experiment 1). The yield of cuttings with releasing time 20 days after planting the mother plants had higher by 60~77% and 104~176% for each cultivar than 40 days and 60 days, respectively (Experiment 2). From these results, in case of propagating the seedlings from cuttings needed for field planting around September 15, early planting around in the latter part of February is the best for cuttings yield. In addition, releasing after the removal of the runners produced from mother plants by 20 days after planting gives an advantage over higher yield of cuttings. Consequently, this study suggest to apply an efficient raising seedling system for labor saving and quality improvement in raising seedlings of three strawberry cultivars in Korea.

• Journal of Wetlands Research
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• v.22 no.2
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• pp.81-91
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• 2020

As part of method for ecologically utilizing abandoned paddy, potential of the abandoned paddy as a target site for ex-situ conservation of 9 endangered species of different life form was confirmed by considering the nature of rice paddy. In order to create Dum-bung, a component of traditional Korean rice paddy, a part of the abandoned paddy was modified to change the water environment. The seeds, asexual reproductive and sexually reproductive individuals of each endangerd species were transplanted into the abandoned paddy to observe the survival rate and phenological response for 1 year, and then monitored for 2 years. As a result, Hydrophyte 4 taxa (Euryale ferox, Saururus chinensis, Dysophylla yatabeana, Menyanthes trifoliata), Geophyte taxa 1 (Epilobium hirsutum), and Hemicryptophyte taxa 1 (Cicuta virosa) could be introduced into the abandoned paddy. In particular, Euryale ferox, Dysophylla yatabeana, and Menyanthes trifoliata should be introduced into Dum-bung, and Saururus chinensis, Epilobium hirsutum, and Cicuta virosa should be introduced into paddy wetland. Growth of Euryale ferox and Brasenia schreberi was inhibited by herbaceous species, and the growth of Epilobium hirsutum was inhibited by herbivores. Therefore, in order to help efficient settlement of endangered plants introduced in abandoned paddy, it is necessary to remove herbs that inhibit growth and to manage herbivores. In addition, it is necessary to prevent the collapse of paddy bank by planting on the paddy field trees or herbaceous forming vegetation mat. When using abandoned paddy ecologically, it is effective to diversify the moisture environment by creating a Dum-bung to increase biodiversity.