• Korean Journal of Environmental Agriculture
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• v.41 no.4
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• pp.355-364
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• 2022

BACKGROUND: Pre-harvest interval and decline pattern of thiamethoxam were determined in kiwifruit using liquid chromatography-tandem mass spectrometry (LCMS/MS). The study was carried out to propose import tolerance using OECD maximum residue limit (MRL) calculator for the export promotion of kiwifruit to Taiwan. METHODS AND RESULTS: The thiamethoxam residue in kiwifruit was determined by using the LC-TriQ-MS/MS with the analytical process to set up the import tolerance under greenhouse conditions for Taiwan. Excellent linearity was observed for all of the analytes with a determination coefficient (R²)≥0.99. The limit of quantification was determined to be 0.01 mg/kg for both thiamethoxam and clothianidin in kiwifruit. Linearity was determined from the co-efficient of determinants (R²) obtained from the seven-point calibration curve. The standard calibration curve showed as follows; 1) Site 1 (Gimje): y = 944,406X + 1,583 (R²=0.9995), 2) Site 2 (Goheung): y = 1,356,205X + 934 (R²=0.9983), and 3) Site 3 (Jangheung): y = 1,239,937X - 3,090 (R²=0.9908). The residue of thiamethoxam in the kiwifruit for three decline trials showed the range of 0.35 to 0.56 mg/kg in site 1 (Gimje), 0.24 to 0.55 mg/kg in site 2 (Goheung), and 0.28 to 0.42 mg/kg in site 3 (Jangheung), respectively. However, clothianidin was not detected in all of the treatments. The maximum residual amounts (decline) in the samples, sprayed according to the safe-use standard for thiamethoxam 10% WG in kiwifruit (30 days before harvest, 3 sprays every 7 days) were 0.56 mg/kg in site 1, 0.55 mg/kg in site 2, and 0.42 mg/kg in site 3, respectively. CONCLUSION(S): The import tolerance (IT) of thiamethoxam for kiwifruit may be proposed to be 0.9 mg/kg by using the OECD MRL calculator.

• Korean Journal of Environmental Agriculture
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• v.39 no.4
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• pp.343-351
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• 2020

BACKGROUND: Irrigation water is known to be one of the major sources of bacterial contamination in agricultural products. In addition, anti-microbial resistance (AMR) bacteria in food products possess serious threat to humans. This study was aimed at investigating the prevalence of foodborne bacteria in irrigation water and evaluating their anti-microbial susceptibility. METHODS AND RESULTS: Surface water (n = 66 sites) and groundwater (n = 40 sites) samples were collected from the Gyeongi and Gangwon provinces of South Korea during April, July, and October 2019. To evaluate the safety of water, fecal indicators (Escherichia coli) and foodborne pathogens (E. coli O157:H7, Salmonella spp., and Listeria monocytogenes) were examined. E. coli isolates from water were further tested for antimicrobial susceptibility using VITEK2 system. Overall, detection rate of foodborne pathogens in July was highest among three months. The prevalence of pathogenic E. coli (24%), Salmonella (3%), and L. monocytogenes (3%) was higher in surface water, while only one ground water site was contained with pathogenic E. coli (2.5%). Of the 343 E. coli isolates, 22.7% isolates were resistant to one or more antimicrobials (ampicillin (18.7%), trimethoprim-sulfamethoxazole (7.0%), and ciprofloxacin (6.7%)). CONCLUSION: To enhance the safety of agricultural products, it is necessary to frequently monitor the microbial quality of water.

• Tunnel and Underground Space
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• v.19 no.6
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• pp.526-533
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• 2009

This study presents Mine Green Framework(M.G.F) which can protect the slope of rock and tailings. M.G.F method provides the fiber frame which helps the growth of the plant in the barren site like mined rock slope. M.G.F system consists of the polyester fiber mat, soil, seeds and anchors for the attachment. The optimum rate of filling materials was figured out by many germination tests in order to improve the effect of filling materials and the optimum rate of filling materials was applied in four test sites individually. High rooting rate over 70% was confirmed in all field tests. Especially the moisturizer was the most important component of filling materials and it could make the better condition for the plants.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.3 no.2
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• pp.35-46
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• 2000

Environmental pollution has become more and more serious in urban areas since industrialization as most streams and rivers were developed heavily because of economic opportunism. Recently river restoration techniques, applied in advanced countries, have been introduced to Korea. But the application of river restoration techniques developed in advanced countries, has a lot of limitations in respect of economic loss during construction, suitability for the domestic situation and the problem of flood control. The method of minimizing the problems must take into consideration these issues, including economic considerations. So from these points of view this study intends to plan ecological river restoration and to create a nature friendly river in the case of the Chungrang river. The subject site is the upper part of Chungrang river, from the Nokchun bridge to Sang-kye bridge, where the ecosystem is well preserved in comparison with other parts of the river. The subject site is divided into 10 sections for plant state investigation. The result of plant-state investigation showed pioneer water plants such as Persicaria thunbergii, Oenanthe jaranica, Rumex crispus. appeared very often. On the basis of the existing plant state, this study has planned an appropriate plant state for the river and has planned for bank protection using a method of construction, which is suitable for natural river. In this study, first of all, it is intended to investigate the plant growth state of Chungrang river and try to plan a particular ecosystem for the river for the purpose of the revival of the natural river.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.13 no.4
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• pp.18-29
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• 2010

The vascular plants in ecological forest site on the Gujaebong (Mt.), Hadong were listed 338 taxa; 85 families, 219 genera, 290 species, 1 subspecies, 40 varieties and 7 forms. Divided into 338 taxa; woody plants were 121 taxa (35.8%) and herbaceous plants were 217 taxa (64.2%). Based on the legal protection species, endangered wild plants II were recorded; Aconitum austro-koreense, Corylopsis gotoana var. coreana and rare plants (IUCN) by the Korea Forest Service and Korea National Arboretum 5 taxa were recorded; Botrychium virginianum, Aconitum austro-koreense, Coreanomecon hylomecoides, Corylopsis gotoana var. coreana, Viola albida. Based on the list of Korean endemic plants, 13 taxa were recorded; Cephalotaxus koreana, Thalictrum actaefolium, Vicia nipponica, Indigofera koreana, Stewartia koreana, Weigela subsessilis, etc. Based on the list of approved for delivering overseas of plants, 5 taxa were recorded; Coreanomecon hylomecoides, Vaccinium oldhami, Paulownia coreana, Asperula lasiantha, Carex okamotoi. Specific plant species by floral region were total 21 taxa (6.2% of all 338 taxa of vascular plants); Aconitum austro-koreense, Corylopsis gotoana var. coreana in class V, Cimicifuga heracleifolia, Coreanomecon hylomecoides in class IV, 4 taxa (Stewartia koreana, Phacellanthus tubiflorus, Lonicera subhispida, etc.) in class III, Potentilla dickinsii, Viola orientalis in class II, 11 taxa (Aconitum jaluense, Angelica anomala, Erythronium japonicum, etc.) in class I. The naturalized plants in the surveyed sites were 8 families, 15 genera, 15 taxa (Phytolacca americana, Crassocephalum crepidioides, Lolium perenne, etc.) and naturalization rate was 4.4% of all 338 taxa of vascular plants.

• Journal of Radiation Protection and Research
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• v.37 no.4
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• pp.197-201
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• 2012

Annual dose at the boundary of the interim storage facility at normal condition was calculated to estimate the site area of the facility of PWR spent nuclear fuel. In this work, source term was generated by ORIGEN-ARP for 4.5 wt% initial enrichment, 45,000 MWd/MTU burnup and 10 years cooling time. Modeling of the storage facilities and radiation shielding evaluations were conducted by MCNP code depending on the storage capacity. In the case of the centralized storage system, the required site area was found to have the radius of more than 700 m.

• Journal of Advanced Navigation Technology
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• v.15 no.5
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• pp.714-721
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• 2011

In this paper, developing management programs for EMI tracking can navigate the site quickly and solve EMI tracking cause and location to use materials such as analysis of air accidents, EMI site location data of 1000 RF companys, radio wave spectrum analysis and audio data. these data are databased and used comparable data. Also, EMI has been prevented by establishing continuous monitoring system through a 24-hour surveillance. Therefore we were able to provide high quality air waves in order to prevent aircraft accidents. In addition, radar control staff of Korea Airports Corporation against passenger aircraft that will prevent the worst aircraft accident have been established based to continue periodic aviation frequency protection and Portable Electronic Devices(PED) on board aircraft to prevent the culture of safety campaign.

• BMB Reports
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• v.32 no.5
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• pp.515-520
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• 1999

Incubation of two types of glutamate dehydrogenase isoproteins from bovine brain with the arginine-specific dicarbonyl reagent phenylglyoxal resulted in a biphasic loss of enzyme activity. Reaction of the glutamate dehydrogenase isoproteins with phenylglyoxal caused a rapid loss of 53~62% of the enzyme activities and modification of two residues of arginine per enzyme subunit. Prolonged incubation of the glutamate dehydrogenase isoproteins with phenylglyoxal resulted in the modification of an additional four residues of arginine per enzyme subunit without further loss of the residual activities. Partial protection against inactivation was provided by the coenzyme NADH or substrate 2-oxoglutarate. The most marked decrease in the rate of inactivation was observed by the combined addition of NADH and 2-oxoglutarate, suggesting that the first two modified arginine residues are in the vicinity of the catalytic site. However, inactivation of the glutamate dehydrogenase isoproteins by phenylglyoxal appears to be partial with approximately 40% activity remained after an extended reaction time with excess reagent, suggesting that the modified arginine residues may not be directly involved in catalysis. The lack of complete protection by substrates also suggest the possibility that the modified arginine residues are not directly involved at the active site, and the partial loss of activity by the modification of arginine residues may be due to a conformational change. There were no significant differences between the two glutamate dehydrogenase isoproteins in sensitivities to inactivation by phenylglyoxal, indicating that the microenvironmental structures of the glutamate dehydrogenase isoproteins are very similar to each other.

• Journal of Radiation Protection and Research
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• v.19 no.2
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• pp.109-120
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• 1994

A method for estimating the effectiveness of each protective action against a nuclear accident has been proposed using the fuzzy set theory. In most of the existing countermeasure models in actions under radiological emergencies, the large variety of possible features is simplified by a number of rough assumptions. During this simplification procedure, a lot of information is lost which results in much uncertainty concerning the output of the countermeasure model. Furthermore, different assumptions should be used for different sites to consider the site specific conditions. Tn this study, the diversity of each variable related to protective action has been modelled by the linguistic variable. The effectiveness of sheltering and evacuation has been estimated using the proposed method. The potential advantage of the proposed method is in reducing the loss of information by incorporating the opinions of experts and by introducing the linguistic variables which represent the site specific conditions.

• Journal of Radiation Protection and Research
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• v.23 no.1
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• pp.1-6
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• 1998

A diffusion model of radioactive liquid effluents is developed and applied for YGN NPP's site, based on the Gaussian plume type model. Due to the complexity of oceanic diffusion characteristics of YGN site, a simple and reliable statistical model based on Reg. Guide 1.113 is developed. Also, a computer code package to calculate dilution factors as a function of plant operation conditions and pathway of radioactive materials. A liquid effluents diffusion model is developed by dividing the diffusion range into two categories, i. e, a near field mixing region and a far field mixing region. In the near field, the initial mixing is affected by a buoyance force, a high initial turbulence and momentum which is characterized by a plant operation condition and environmental conditions. The far field mixing is similar to gaseous effluents diffusion. So, beyond the near field region, wellknown Gaussian plume model was adopted. A different area averages of Gaussian plume equation was taken for each radioactive exposure pathway. As a result, we can get different dilution factors for different pathways. Results shows that present dilution factors used for YGN ODCM is too much overestimated compared with dilution factors calculated with the developed model.