• 제목/요약/키워드: Contamination Level

검색결과 1,026건 처리시간 0.037초

폐금속 광산의 토양 중금속 오염 조사 자료 해석을 위한 핫스팟 분석의 적용 (Application of Hot Spot Analysis for Interpreting Soil Heavy-Metal Concentration Data in Abandoned Mines)

  • 이채영;김성민;최요순
    • 한국지리정보학회지
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    • 제22권2호
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    • pp.24-35
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    • 2019
  • 본 연구에서는 핫스팟 분석을 통해 폐금속 광산의 토양 중금속 오염 조사 자료를 통계적 유의수준에 따라 해석할 수 있는 새로운 방법을 제시하였다. 이상 값을 나타내는 토양 중금속 오염 조사 자료들이 특정한 공간에 집중 또는 분산되어 나타나는지를 확인하기 위해 자료들의 공간적 자기상 관성을 Getis-Ord $Gi{\ast}$ 통계량을 이용하여 분석하였다. 그 결과 폐금속 광산지역에서 이상 값을 나타내는 자료들이 통계적으로 얼마나 유의미하게 집중되어 있는지 확인할 수 있었다. 각각의 자료들이 가지는 중금속 원소별 오염도 값과 Getis-Ord $Gi{\ast}$ 통계량 계산 결과를 이용하여 자료들을 (1) 오염도와 집중도가 모두 높은 것, (2) 오염도는 높으나 집중도가 낮은 것, (3) 오염도는 낮으나 집중도가 높은 것, (4) 오염도와 집중도가 모두 낮은 것 중 하나의 유형으로 분류할 수 있었다. 이러한 분류 결과를 활용하면 토양 중금속 오염 조사자료를 통계적 유의수준에 따라 해석할 수 있으며, 폐광산 지역의 토양오염 관리와 관련하여 합리적인 의사결정을 지원할 수 있으리라 판단된다.

염분 오손 자동측정에 관한 연구 (A Study on the Automatic Measurement of Salt Contamination)

  • 곽희로;김한상;권동진;이동준;김경화;조국희
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1995년도 하계학술대회 논문집 C
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    • pp.1362-1364
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    • 1995
  • In this paper, the automatic device for measuring the salt contamination on insulators was developed. The device consists of electronic insulators, measuring system, monitoring system, and printer. It was shown that the level of salt contamination measured by the developed device is similar to that measured by the brush cleaning method. Therefore, the developed automatic measuring device can be used in field, in order to predict the cleaning time of insulators and prevent the failure due to the salt contamination.

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광섬유 센서를 이용한 오일 오염도 검사시스템 연구 (A Study on Oil's Contamination Detection System using Optical Fiber Sensor)

  • 송두상;홍준희;류상현
    • 한국생산제조학회지
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    • 제21권4호
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    • pp.541-546
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    • 2012
  • This study investigates the detection system of oil pollution level using single optical fiber sensor. This study focus on sensing of oil pollution by moisture and iron powder which are representatives of oil pollution factor. In addition, It is placed that the water and iron powder as an oil pollution factor in the oil tank which is the oil circulation in. The oil pollution detection system was measured by the changing of intensity of light and sensing gap. The result of this experimentation not only confirmed the contamination by moisture volume in the oil tank from the section 190ppm to 540ppm, but also monitored the contamination by iron volume from the section 1200ppm to 3500ppm. This study confirmed effectiveness of this detection system using optical fiber sensor. There is expectations of measuring another section by various optical fiber sensor.

Using AP2RC & P1RB micro-silica gels to improve concrete strength and study of resulting contamination

  • Zahrai, Seyed Mehdi;Mortezagholi, Mohamad Hosein;Najaf, Erfan
    • Advances in concrete construction
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    • 제4권3호
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    • pp.195-206
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    • 2016
  • Today, application of additives to replace cement in order to improve concrete mixes is widely promoted. Micro-silica is among the best pozzolanic additives which can desirably contribute to the concrete characteristics provided it is used properly. In this paper, the effects of AP2RC and P1RB micro-silica gels on strength characteristics of normal concrete are investigated. Obtained results indicated that the application of these additives not only provided proper workability during construction, but also led to increased tensile, compressive and flexural strength values for the concrete during early ages as well as ultimate ones with the resulting reduction in the porosity lowering permeability of the micro-silica concrete. Furthermore, evaluation of microbial contamination of the mentioned gels showed the resultant contamination level to be within the permitted range.

소규모 돼지도축공정에서 도체오염 미생물의 변화 (Microbial change of pork carcass during processing in small size slaughterhouse)

  • 홍종해;이경환;이성모
    • 한국동물위생학회지
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    • 제25권1호
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    • pp.31-37
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    • 2002
  • Major hazards existed in slaughterhouse are pathogenic microorganisms originated from intestinal microflora of slaughtered animals. This study was intended for the identification of microbial contamination sources during pork slaughtering in small plants. Total aerobic bacteria, Coliform group, Salmonella spp, Listeria monocytogenes, and Campylobacter jejuni/coli were isolated from the surface sample of pork carcasses. Contamination level among different sampling points of ham, belly and neck did not showed statistical differences. Therefore, the mixed sampling from belly and neck of carcass could be effective for microbiological monitoring. Isolation rates of pathogenic microorganisms showed Salmonella spp 20.9%, Listeria monocytogenes 10.5%, and Campylobacter jejuni/coli 8.1% from 296 sampling points. High prevalence rate of Salmonella spp indicated that the contamination of intestinal microflora occurred due to unsanitary processing control, which required HACCP system in small plants. It was recommended that the prerequisite program should be a key factor for a successful HACCP system implementation especially in small size slaughterhouse.

Effect of Contamination of Liquid Crystal by Spilled Components from Color Filter

  • Kim, Young-Seok;Lee, Jeong-No
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2009년도 9th International Meeting on Information Display
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    • pp.1469-1471
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    • 2009
  • Effect of contamination of liquid crystal on the electrical behavior of liquid crystal display (LCD) by spilled components from color filter layer was investigated. It is noted that the level of contamination was different following the kind of liquid crystal and organic layers. Transmittance curve of LCD cell was shifted by spilled components of color filter and BM materials. C-V curve also showed different behavior following color filter type. The results obtained show the image sticking of LCD can be varied by pairing liquid crystal with color filter materials.

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Study of point defects caused by a thin contamination layer in a-Si TFT-LCD

  • Oh, Jae-Young;Lee, Jae-Kyun;Yang, Moung-Su;Kang, In-Byeong
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2007년도 7th International Meeting on Information Display 제7권1호
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    • pp.845-848
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    • 2007
  • Analysis of point defects invisible by a microscope has been studied on the a-Si thin film transistor panel. The point defects which were named Invisible Point Defect (IPD) is characterized by no particles or distortion of patterns on a pixel structure and randomly distributed on panels. To investigate the IPD, measurements were carried out: gray level driving, transistor transfer characteristic, focused ion beam (FIB), and secondary ion mass spectrometry (SIMS). The results showed that a contamination layer had a bad influence on an active surface. The contamination layer consisted of oxygen and iron from a water supply line during cleaning process. After the process tuning, IPD has been stabilized.

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Remediation of Contaminated Groundwater: Change of Paradigm for Sustainable Use

  • Lee, Jin-Yong;Lee, Kang-Kun
    • 한국지하수토양환경학회지:지하수토양환경
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    • 제18권6호
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    • pp.1-7
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    • 2013
  • Groundwater development and use have been increasing in Korea causing frequent occurrences of related hazards such as groundwater level decline, land subsidence, and groundwater contamination. To tackle these groundwater problems, central and local governments have set-up and maintained many groundwater monitoring programs such as the National Groundwater Monitoring Network and the Groundwater Quality Monitoring Network, which collect very valuable data on the overall status of domestic groundwater to aid proper groundwater management. However, several problems mainly related to the remediation of contaminated groundwater remain unresolved. Recently, there have been some incidents related to the contamination of groundwater, and these have drawn the concern of the Korean people. Although groundwater contamination has been investigated in detail, actual groundwater remediation work has not yet been implemented. The remediation of the contaminated groundwater must begin immediately in order to sustain the eco-system service of clean groundwater and enhance the welfare of the Korean people.

초, 중, 고교 교과서의 식품위생 내용 분석 연구 (An Analysis on the Contents of the Food Sanitation in the Primary, Middle and High School Textbooks)

  • 남철현;변부형;노병의;남원계
    • 한국식품위생안전성학회지
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    • 제9권2호
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    • pp.95-104
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    • 1994
  • A study on food sanitation in school textbooks was performed for 7 months from October 1, 1992 through may 31, 1993. A total of 243 textbooks (77 from elementary school level, 52 from junior high school level and 114 from senior high school level) were reviewed and analyzed. This study was performed in order to develop better method for teaching the subjet of food sanitation to students effectively. The results are as follows: 1) A total number of pages of textbooks dealing with food sanitation were 48 pages (0.53%) in elementary level textbooks, 38.05 pages (0.31%) in junior high school level and 105.05 pages (0.34%) in senior high school level. 2) 104.05 pages were allocated for the subject of food storage, 33 pages for insect and rodent control, 32 pages for food poisoning, 15 pages for food contamination and 7 pages for kitchen hygiene. 3) Of the four categories of textbooks, the numbr of pages dealing with food sanitation were 145 in home economics, 31 in physical education, 12 in social studies and 3.0 in science. 4) Home economics and physical education textbooks allocated many pages in dealing with food sanitation. Home economics textbooks had 88 pages for food storage, 26.05 pages for food poisoning, 7 pages for food contamination, and 2 pages for kitchen hygiene. Physical education textbooks had 15 pages about food storage, 4 pages for food poisoning, 5 pages for food contamination, and 1 page for kitchen hygiene. 5) Social studies textbooks had 5 pages for food storage, 4 pages for insect and rodent control, 3 pages for food contamination. 6) The number of pages dealing with food sanitation in elementary school level textbooks were 20 in physical education, 13 in home economics, 12 in social studies, 3 in science respectively. 7) The number of pages dealing with food sanitation in junior high school level textbooks were 31.05 in home economics, and 7.00 in physical education textbooks. 31.50 pages were about food storage, 6 pages about food poisoning, 13 pages about insect and rodent control, and 1 page about kitchen hygiene. 8) The number of pages dealing with food sanitation in senior high school level textbooks were 101.05 in home economics and 4 in physical education textbooks. 64 pages were about food storage, 21.05 about food poisoning, 13 about insect and rodent control, 4 about kitchen hygiene, and 3 about food contamination. 9) Pictures, drawings and tables were used in explaining food sanitation in the textbooks, 32 drawings of a total of 38 cuts in elementary school level textbooks, 8 pictures of 10 cuts in junior high school level and 13 tables of 14 cuts in senior high school level were used. 10) 5th grade textbooks of elementary school did not have a subject on food poisoning. Other grade textbooks in elementary school level did not contain a subject on food contamination and insect and rodent control. It's recommended that these subjects be contained in the textbooks. 11) It is necessary to teach a subject on health or health and environment independently and contain food sanitation in the subject. It is recommended that a textbook on health or health and environment be published and taught to students. 12) It is recommended that teachers specialized in health education be assigened to schools to teach health related subjects. 13) It is recommended that book publishers use the latest information in the textbooks and technical terms be unified.

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빙과류의 미생물학적 위해요소에 대한 노출평가 (Exposure Assessment of Microbiological Risk Factors from Edible Ices)

  • 김태웅;최재호;박경진;오덕환
    • 한국식품위생안전성학회지
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    • 제24권3호
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    • pp.226-231
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    • 2009
  • 본 연구는 위해 미생물에 대한 빙과류의 오염수준 모니터링 결과를 바탕으로 미생물 위해평가(Microbial risk assessment : MRA)를 적용하여 노출정도를 평가하였다. 그 결과 원재료에서 S. aureus 균의 오염수준이 높았으며 살균 전 혼합액에서는 오염수준이 더욱 증가한 것으로 나타났으나 살균 후 혼합액에서는 오염 수준이 현저하게 감소하는 것으로 나타났다 한편 최종 냉동 저장된 빙과류에서의 오염수준은 초기의 원재료 오염수준보다 약간 더 감소하는 것으로 나타났다. 최종적으로 빙과류의 위해성 평가 결과, 빙과류를 1일 동안 1인이 섭취하였을 때 평균적으로 식중독에 걸릴 가능성은 최소 $5.89{\times}10^{-7}$, 최대 $5.01{\times}10^{-5}$의 발생가능성을 제시할 수 있다. 하지만 좀 더 현실적인 위해 수준을 추정하기 위해서는 빙과류의 섭취량, dose-response model(양-반응 모델) 등에 연구가 이루어져야 할 것이다.