• 설비공학논문집
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• 제17권4호
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• pp.333-340
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• 2005

Horizontal air-jet effect has been utilized in some air conditioning systems in order to control the contaminated air indoor. In the present study, the flow and heat transfer of the contaminated air from a range hood system has been investigated with or without horizontal air-jet effect when the hood fan is on or off. For the present numerical experiment, PAT Flow code has been used. From the present numerical simulations, it has been shown that the air jet of a range hood generates coanda effect confining the contaminated air in a certain region. Furthermore, the qualitative relation between the flow rate of the capture air jet and the distribution pattern of the contamination has been discussed.

• 한국물환경학회지
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• 제24권5호
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• pp.523-532
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• 2008

A phase II site investigation and feasibility study was conducted at a military mortar shooting range near the demilitarized zone (Kyunggi, South Korea) to assess the extent of contaminants migration to the nearby Imjin river in which a flood control dam is under construction. The results showed that silty-clay soils around target areas were co-contaminated with heavy metals (Cd, Cu, and Pb) and explosives (HMX, RDX, and TNT). The total amount of contaminant was estimated to be 497.1 kg-RDX, 20.6 kg-HMX, 1.4 kg-TNT, 35.2 kg-Cd, 4,331 kg-Cu, and 5,115 kg-Pb, respectively. Both heavy metals and explosives were almost equally distributed on each soil particle size fraction. Neither subsurface soil samples nor ground water samples showed signs of contamination above the environmental criteria. The major migration route of contaminants was soil particles in surface run-off during rain at which a mass discharge rate of 30.0 mg-RDX/hour was observed.

• Journal of Radiation Protection and Research
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• 제25권1호
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• pp.21-30
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• 2000

벼의 방사성 핵종 직접오염 경로를 분석하기 위하여 동위원소 실험온실내에서 $^{54}Mn,\;^{57}Co,\;^{85}Sr,\;^{134}Cs$의 혼합용액을 벼의 생육중 여섯 차례에 걸쳐 작물체 지상부에 처리하였다. 작물체 차단계수는 핵종 간에 차이가 없었고 처리시기가 수확기에 가까울수록 증가하여 최고 약 0.94에 달리하였다. 작물계에 침적한 각 핵종의 수확시 잔류율은 방사능 붕괴가 없다고 가정할 예 처리시기에 따라 각각 $19{\sim}47%,\;17{\sim}43%,\;19{\sim}42%,\;23{\sim}61%,\;11{\sim}69%$였다. 종실 전류계수는 처리시기에 따라 각각 $6.9{\times}10^{-4}{\sim}3.8{\times}10^{-2},\;3.6{\times}10^{-3},\;1.6{\times}10^{-1}{\sim}5.8{\times}10^{-4}{\sim}3.2{\times}10^{-2},\;1.6{\times}10^{-4}{\sim}7.6{\times}10^{-5},\;3.2{\sim}10^{-2}{\sim}2.0{\times}10^{-1}$의 범위였고 모두 종실의 발육성기 처리시 가장 높았다. 강우 빈도의 차이가 2배 이내일 때는 강우빈도가 잔류율과 전류계수에 큰 영향을 미치지 않는 것으로 나타났다. 본 연구결과는 벼의 생육중 사고침적시 쌀알 내 핵종농도 예측에 활용될 수 있다.

• Environmental Analysis Health and Toxicology
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• 제23권3호
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• pp.143-164
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• 2008

Concern about perfluorinated compounds (PFCs) is growing nationally as well as globally. PFCs could be considered emerging POPs due to their environmentally persistent, bioaccumulative, and potentially harmful properties. Moreover. perfluoroalkylates (PFAs) such as PFOS and PFOA are reported to experience long-range transport (LRT) to the Arctic in spite of their low volatility and strong solubility. The possible pathways contributing to LRT have been proposed but are still in debate in combination with unclear source definition and uncertain physico-chemical properties. The environmental fate of PFCs is more complicated because of the presence of precursors that are degraded to PFAs and are extremely different from their daughters, PFAs. in physico-chemical properties. To what extent and through what pathways are human and wildlife exposed is determined by the environmental fate and distribution of PFCs. To define uncertainties in fate and distribution thus is critical to prevent erroneous policy and/or determination related with exposure and risk reduction. This article aimed to review controversy and/or uncertain issues for the environmental fate and distribution of PFCs and to prospect research topics necessary to dissolve uncertainties.

• 한국동물위생학회지
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• 제27권1호
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• pp.7-15
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• 2004

For measuring general bacterial count and Escherichia coli count, the standard plate count was used to conduct a test on 113 cases of pork carcass surfaces from slaughterhouses in Incheon area from January to February 2003. And Salmonella spp, Staphylococcus aureus and Listeria monocytogenes was used to conduct a test on 68 cases of pork carcass surfaces and 76 cases of feces, that is to say, a total of 144 cases. The results were obtained as follows: In the case of general bacterial count, 29 cases(25.7%) were in the range of 100∼999 and 62 cases(54.9%) were in the range of 1,000∼9,999 and 22 cases(19.4%) were in the range of 10,000∼99,999. Meanwhile as regards E coli count, 22 cases(19.4%) were in the range of 1∼9 and 69 cases(61.2%) were in the range of 10∼99 and 22 cases(19.4%) were in the range of 100∼999. On 68 cases of pork carcass surfaces, 7 strains(10.2%) of Salmonella spp, and 12 strains(17.6%) of S aureus were detected and 27 strains(39.7%) of L monocytogenes, respectively. As for the detected Salmonella spp, 6 strains of the B group, 3 strains of S enterica subsp salame and 2 strains of S typhimurium were detected, respectively. On 76 cases of feces, 14 strains(18.4%) of Salmonella spp, and 15 strains(19.7%) of L monocytogenes and 14 strains(18.4%) of S aureus were detected respectively. As for the detected Salmonella spp, 6 strains of the B group, 4 strains of S derby and 8 strains of the C group, 5 strains of S rissen were detected, respectively. All of 42 strains of L monocytogenes were type 1. As a result of conducting a toxin test on the detected S aureus, all of 26 strains were found to be non-toxin.

• 생명과학회지
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• 제18권3호
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• pp.395-402
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• 2008

본 연구는 2007년 6윌부터 10월까지 제주도에서 양식장이 가장 많이 밀집되어 있는 제주도 동부 연안에 위치한 양식장 4개소를 대상으로 하여 사육 용수, 양어 사료, 양식 넙치의 미생물학적 오염도를 조사하였다. 식품병원성 미생물 중 일반세균과 총대장균군 그리고 Escherichia coli O157:H7, Salmonella spp., Vibrio parahaemolyticus, Staphylococcus aureus, Bacillus cereus를 조사 하였다. 이번 연구를 수행하는 동안 동부지역은 집중적인 호우로 인해 전년보다 400 mm 이상의 많은 강우량을 나타내었다. 사육 용수의 검사결과 V. parahaemolyticus, Salmonella spp., S. aureus, B. cereus가 빈번하게 검출되었고, 양어 사료의 경우 Salmonella spp, S. aureus, B. cereus는 각각 $0{\sim}4.3{\times}l0^3$ CFU/ml, $0{\sim}2.7{\times}l0^4$ CFU/ml, $0{\sim}7.6{\times}l0^3$ CFU/ml 검출 되었다. 또한 양식 넙치의 미생물 검사 결과 적은 양이지만 Salmonella spp., S. aureus, B. cereus가 검출되었고, 총대장균군과 E. coli Ol57:H7은 검출되지 않았다. 이번 조사 결과로 보아 미생물학적 위해요소는 양식장의 작업 환경이나 주변 환경 등의 환경적 요인이 크게 작용하는 것으로 사료되며, 양식장의 위생관리에 작업자들은 주의를 기울여야 할 것으로 생각된다. 앞으로 이와 관련하여 수산물 위생에 대한 좀 더 체계적인 시스템을 도입하여 적용한다면 수산물에서 야기되는 문제점들이 해결되어 제주도의 청정 브랜드의 이미지를 더욱 부각시킬 수 있으며, 안전하고 깨끗한 수산물의 생산이 가능할 것으로 생각된다.

• 한국수산과학회지
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• 제52권4호
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• pp.344-348
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• 2019

This study assessed the microbiological hazards of gloves worn during the shell shucking process of the oyster Crassostrea gigas, and we suggest an in situ method for minimizing microbial contamination. The study consisted of two groups, one in which the working gloves were periodically replaced (PRG) with new gloves, and another in which the gloves were not replaced (NRG). In the PRG group, gloves were replaced every 2 h during 8 h of processing. Food pathogenic bacteria Escherichia coli, Salmonella species, and Listeria monocytogenes were not found in any samples, including gloves and shucked oysters. However, Staphylococcus aureus (SA) was detected in some samples, and the contamination levels were correlated with the working time and the regular replacement of gloves. SA was not detected on gloves or oysters of the PRG group. However, it was detected in the range of <$15CFU/15cm^2$ to $2.9{\times}10^2CFU/15cm^2$ on gloves after 6 h of continuous work, and from <$15CFU/15cm^2$ to $2.23{\times}10^2CFU/15cm^2$ on oysters after 8 h. These results indicate that the SA contamination in shucked oysters originated from the working gloves, and that replacement of working gloves every 2-4 h will minimize SA contamination in oyster products.

• 대한수의학회지
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• 제51권1호
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• pp.47-53
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• 2011

In Korea, groundwater is main water source in livestock farms. Most dairy and cattle farms have constructed their own wells for human drinking and livestock farming. However, these private residential wells have not been controlled by government and also there was scant study about livestock drinking water quality. Therefore this study was to monitor of the livestock farms' groundwater quality in Korea. Water samples were collected at 123 dairy and cattle farms and were analysed forty six substances with quality standard for drinking water approved by the Minister of Environment. Seventy eight (63.4%) of 123 samples failed to drinking water stand a test. The most frequent contaminants were nitrate-nitrogen and microbial. 22.8% (n=28) of samples showed nitrate-N concentration of higher than 10 mg/L meant that can't be used drinking water for human and the Nitrate-N concentration analysed in the range of 0.2 to 61.2 mg/L. All of 78 failed to drinking samples had microbial problems, especially 5.7% (n=7) of samples indicated water could be contaminated by feces. Other contaminants detected were zinc and evaporation residue. Especially detected zinc concentration (32 mg/L) was about ten times higher than standard of zinc (3 mg/L). Regression analysis indicated that groundwater pH did not influence to nitrate-N concentration but the hardness and chloride could affect to nitrate-N concentration in the groundwater. Most livestock farms were adjacent to crop farmland in Korea. This could cause contamination of groundwater with nitrate-N and pesticide that could accumulate livestock product. Moreover Heavy metal such as zinc and copper could be released from a corrosive plated water pipe in livestock farm. Put together, Korea livestock system is indoor, not pasture-based, hence livestock could be exposed to potential contaminated water consistently. Therefore on the basis of these data, appropriate livestock drinking water quality standards should be prepared to keep livestock healthy and their product safe. Further, livestock drinking water quality should be monitored continuously in suitable livestock drinking water standards.

• 한국식품위생안전성학회지
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• 제33권2호
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• pp.94-101
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• 2018

본 연구에서는 김치 제조시 철저한 재료 세척의 필요성을 확인하고, 더불어 비가열 식품인 김치의 위생 안전성 실태를 파악하여 효율적 미생물 저감화 방안을 마련하고자 국내에서 유통되는 김치 원 부재료 200건의 세척 전과 후의 비교분석과 시판 김치 100건에 대하여 미생물 분석을 실시하였다. 김치 원 부재료 및 완제품에 대하여 일반세균수, 대장균 및 대장균군을 모니터링 하였으며, 병원성 미생물 9종(Bacillus cereus, Clostridium perfringens 정성 정량, Staphylococcus aureus, Enterohemorrhagic Escherichia coli, Campylobacter jejuni/coli, Yersinia enterocolitica, Salmonella spp., Vibrio parahaemolyticus, Listeria monocytogenes 정성)을 분석 하였다. 모니터링 결과, 김치 원 부재료 및 완제품에서 일반세균은 1.4~9.0 log CFU/g 수준으로 확인되었으며, 원 부재료 중 생강에서 8.8 log CFU/g, 완제품 중 총각김치에서 9.0 log CFU/g으로 일반세균이 가장 높게 나타났다. 대장균군은 0.5~7.3 log CFU/g으로 확인되었으며, 생강에서 7.3 log CFU/g으로 가장 높게 나타났고, 병원성 미생물 9종의 분석결과, Bacillus cereus를 제외한 나머지 8종의 식중독균은 모든 시료에서 검출되지 않았다. 김치 제조 시 사용되는 김치 원 부재료들의 세척공정 후 미생물 수는 일반세균수 0.2~3.2 log CFU/g, 대장균군 0.3~2.7 log CFU/g, Bacillus cereus 1.0~3.9 log CFU/g 감소하였다. 따라서, 김치 원 부재료의 세척 공정으로 미생물 오염도를 감소 시켰으며, 이 결과를 통하여 김치 완제품의 위생 및 저장성 증진에 기여 할 수 있을 것으로 확인되었다.

• Parasites, Hosts and Diseases
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• 제54권1호
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• pp.113-118
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• 2016

Hydatidosis has become a real concern for health care institutions and animal rearers in Tunisia. The Tunisian endemicity is aggravated by the growing number of dogs and the difficulty of getting rid of contaminated viscera because of the lack of equipment in most slaughterhouses. Therefore, microscopic and molecular tools were applied to evaluate the role of slaughterhouses in canine infection and Echinococcus granulosus sensu lato (s. l.) egg dissemination. Exposure risk to E. granulosus s. l. eggs in urban and rural areas was explored in order to implant preventive and adapted control strategies. Microscopic examinations detected taeniid eggs in 152 amongst 553 fecal samples. The copro-PCR demonstrated that 138 of 152 taeniid samples analyzed were positive for E. granulosus s. l. DNA. PCR-RFLP demonstrated that all isolated samples belonged to E. granulosus sensu stricto (s. s.). An important environmental contamination index (25.0%) by E. granulosus s. l. eggs was demonstrated. The average contamination index from the regions around slaughterhouses (23.3%; 95% CI: 17.7-28.9%) was in the same range as detected in areas located far from slaughterhouses (26.0%, 95% CI: 21.3-30.8%). Echinococcosis endemic areas were extended in both rural (29.9%, 95% CI: 24.8-34.9%) and urban locations (18.1%, 95% CI: 13.0-22.9%). The pathogen dissemination is related neither to the presence/absence of slaughterhouses nor to the location in urban or rural areas, but is probably influenced by human activities (home slaughtering) and behavior towards the infected viscera.