• 제목/요약/키워드: Contamination sources

검색결과 366건 처리시간 0.029초

DOT-3 브레이크액에서 오염에 따른 광학적 특성 연구 (A study of the Optical Characteristics for Contaminated Brake Fluid, DOT-3)

  • 지인근;김여환
    • 한국정보전자통신기술학회논문지
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    • 제8권5호
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    • pp.354-358
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    • 2015
  • DOT-3 규격의 자동차 브레이크액에 대하여 수분 함유량과 시스템 마찰로 인한 오염도를 전기저항과 광학 투과율을 측정하여 비교하였다. 기존의 저항측정법은 수분 함유량을 주로 측정하는 반면에 광학 투과율 방식은 제동장치 내부의 마찰에 의하여 발생된 입자의 오염을 포함하여 측정할 수 있어서 저항변화 측정보다는 광학 투과율 방법이 더 선형적이고 효율적이었다.

호소 및 하천의 오염 저질토 sampling 방법 및 처리방안 연구

  • 최동호;배우근;최형주
    • 한국지하수토양환경학회:학술대회논문집
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    • 한국지하수토양환경학회 2003년도 총회 및 춘계학술발표회
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    • pp.115-119
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    • 2003
  • Pollutants from industry, mining, agriculture, and other sources have contaminated sediments in many surface water bodies. Sediment contamination poses a severe threat to human health and environment because many toxic contaminants that are barely detectable in the water body can accumulate in sediment at much higher levels, the purpose of this study was to make convenient sampling method and optimal treatment of sediment for water quality improvement in reservoir or stream based on an evaluation of degree of contamination. Results for analysis of S-reservoir sediments were observed that copper concentration of almost areas were higher than the regulation of soil pollution (50 mg/1) for the riverbed. S-stream sediments were observed that copper, arsenic and TPH concentration of almost areas were exceeded soil pollution concerning levels for factorial areas. We used Remscreen(version. 1.0) program which is contaminated soil recovery program to select optimal treatment method of contaminant sediments. The result was shown in the order of Thermal Calcination > Excavation, Retrieval and Off-site Disposal(comparative less then contaminant) > Low Temperature Thermal Desorption + Solidification/Stabilization.

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Rapid and accurate identification of microorganisms contaminating cosmetic products based on DNA sequence homology

  • Jita, Yuriko-Fu;Hiroharu Shibavama;Yasuhiro Suzuki;Syuichi Karita;Susumu Takamatsu
    • 대한화장품학회:학술대회논문집
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    • 대한화장품학회 2003년도 IFSCC Conference Proceeding Book II
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    • pp.448-455
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    • 2003
  • Because cosmetics are applied directly to human skin, contamination of such products by microorganisms should be carefully avoided. Since cosmetics are usually kept at room temperature and contain large amounts of nitrogen and carbon sources, they may easily become contaminated by a variety of microorganisms, such as bacteria, filamentous fungi, and yeasts. The rapid and accurate identification of these microorganisms is essential to prevent further expansion of such contamination and the damage it causes. However, more than 30 days and laboratory skills are usually necessary in order to identify microorganisms in cosmetic materials. These time and labor constraints may allow further damage of the cosmetic products and thereby harm the consumer.(omitted)

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Development of Ceramic Arc-tube by the PIM Process

  • Rhee, Byung-Ohk;Choi, Seung-Chul;Park, Jeong-Shik;Kim, Byoung-Kyu;Kim, Hyung-Soo;Kim, Sang-Woo
    • 한국분말야금학회:학술대회논문집
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    • 한국분말야금학회 2006년도 Extended Abstracts of 2006 POWDER METALLURGY World Congress Part 1
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    • pp.205-206
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    • 2006
  • A ball-shape alumina arc-tube for low-wattage lamp was developed by the PIM process. An ultra high purity translucentgrade alumina powder was used. In injection molding process, a hot-runner type mold was developed. The translucent-grade alumina powder was extremely sensitive to contamination so that the injection molding condition and atmosphere control in the furnace should be taken care of with extreme caution. Contamination sources were pinpointed with EPMA. The arc-tube was molded in half and two halves were bonded in the middle by a new bonding technique at room temperature developed in this study.

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삼파장 4채널 적외선식 불꽃감지기의 자가진단 성능 개선 (An Improvement on the Self Diagnostic Characteristics of the Triple Quard Channel Infrared Flame Detector)

  • 송현선
    • 조명전기설비학회논문지
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    • 제30권1호
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    • pp.49-54
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    • 2016
  • There is needed the quard channel triple wave lengths pyroelectric infrared flame detector to recognize the unique characteristics of fire sources in various type. This system detects the triple wave lengths of infrared flame emitting maximum radient energy and scattering frequency of flame. The quard channel infrared flame detector detects the duplicate wave lengths of maximum radient energy to enhance the accuracy of detecting fire. Especially this paper focuss on development of the self diagnosis function system including contamination, temperature and input voltage. Therefore, the prevention and early suppression of fire is available.

지하수 상수원 활용의 타당성 고찰을 위한 상수도 취수원의 특성 비교 연구 (A Comparison Study of Various Water Sources for Feasibility of Expanding the use of Groundwater in Public Water Supply of South Korea)

  • 차은지;현윤정
    • 한국지하수토양환경학회지:지하수토양환경
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    • 제22권4호
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    • pp.60-70
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    • 2017
  • As water sources become more vulnerable to the effects of climate change such as drought and contamination, the diversification of water sources is important for securing water supply. This study examines the properties of five water sources for public supply, including river and river-bed water, dams, reservoirs, and groundwater, while ensuring that the quantities available from such sources are stable and the water itself is safe for use. This study also analyzes the power, chemical, repair and maintenance, and labor costs associated with each water source. The results demonstrate that groundwater has high potential as a water source because it is readily available (about $12.89billion\;m^3/yr$), but only a small portion of it is currently used. Analyses indicated that groundwater is the most efficient source of water to meet water demand below $1,000,000m^3/yr$, which covers 62.5% of water supply facilicities. With the implementation of groundwater dams, groundwater can become cost-efficient even for larger water demand. Additionally, the water source protection areas are the smallest for groundwater among the five water sources. In conclusion, the use of groundwater as an alternative water source is feasible becasue it is readily available, safe, cost-efficient, and requires the lowest amount of environmental regulations for the diversification of water supply sources.

휴대용 XRF와 GIS를 이용한 폐광산 지역의 토양오염에 관한 연구 (A Study on the Soil Contamination(Maps) Using the Handheld XRF and GIS in Abandoned Mining Areas)

  • 이현규;최요순
    • 한국지리정보학회지
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    • 제17권3호
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    • pp.195-206
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    • 2014
  • 본 연구에서는 휴대용 X-선 형광 분석기(X-Ray Fluorescence, XRF)와 지리정보시스템(Geographic Information Systems, GIS)을 이용하여 부산 폐광산 지역의 구리와 납에 관한 토양오염지도를 작성하였다. 연구지역의 수치표고모델(Digital Elevation Model, DEM)을 이용한 수문 분석을 통해 오염원으로부터 오염 물질이 확산될 수 있는 빗물의 흐름방향을 분석하였으며, 이를 고려하여 토양오염도 측정 지점을 24곳 선정하였다. 휴대용 X-선 형광 분석기를 이용하여 24곳 토양에서 구리와 납의 농도를 측정한 결과, 구리는 최대 8,255ppm, 납은 최대 2,146ppm가 검출되었다. 휴대용 X-선 형광 분석기로 측정한 구리와 납의 농도 자료를 ArcGIS 소프트웨어에 입력하였으며, 정규크리깅(ordinary kriging) 기법을 이용하여 공간보간(spatial interpolation)을 수행한 후 구리와 납에 관한 5m 해상도의 토양오염지도를 작성하였다. 그 결과 부산 폐광산 지역에서는 갱구들 주변에 적치되어 있는 폐석 및 광미를 중심으로 고농도의 구리와 납이 토양 내에 존재하는 것을 작성된 토양오염지도로부터 확인할 수 있었다. 본 연구를 통해 휴대용 X-선 형광 분석기와 GIS를 이용한 구리와 납의 토양오염지도 작성방법이 현장에서 효과적으로 사용될 수 있음을 알 수 있었다.

DRASTIC과 지하수 수질에 의한 창원시 지하수 오염취약성 평가 (Assessing Groundwater Vulnerability Using DRASTIC Method and Groundwater Quality in Changwon City)

  • 함세영;정재열;김무진;김인수;황한석
    • 자원환경지질
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    • 제37권6호
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    • pp.631-645
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    • 2004
  • 본 연구는 DRASTIC 기법과 지하수 자료를 이용하여 창원시의 공단지역과 주거상업지역의 지하수 오염취약성을 평가하였다. DRASTIC 기법은 원래 오염원이 지표에 있으며 강우의 침투와 함께 오염물질이 지하수로 유입되는 조건에 적용시켰었다. 공단지역은 대체로 주거상업지역보다 높은 DRASTIC 평가지수를 가진다. 그러나, 주거상업지역 중 용지동지역은 연구지역 중에서 가장 낮은 DRASTIC 평가지수를 가짐에도 불구하고 지하수 오염정도가 높다. 이러한 사실은 도시지역의 지하수 오염이 과잉양수와 이에 따른 지하수위 하강과 밀접하게 관련된다는 것을 지시한다. 각 동별 최소 DRASTIC 평가지수와 먹는물 수질 부적합의 상관계수는 0.4로서 비교적 낮다. 그러나, 각 동별 최소 DRASTIC 평가지수와 지하수 사용량의 상관계수는 0.70이고, 각 동별 최소 DRASTIC 평가지수와 지하수 공 분포밀도의 상관계수는 0.87로서 높게 나타난다. 따라서, 도시지역에서 지하수 오염취약성을 평가하기 위해서는 기존의 DRASTIC 평가요소뿐만 아니라 지하수 사용량과 지하수 공 분포 밀도와 같은 인위적인 요소도 함께 고려하는 것이 필요하다.

Forty Years of Anthropogenic Radionuclides in Surface Seawater. Italian and Japanese Data

  • Cigna, Arrigo A.
    • Ocean Science Journal
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    • 제41권4호
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    • pp.261-290
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    • 2006
  • The concentrations of man made radionuclides in surface seawater since early '60s are here reported as measured in Italy and Japan. Most of the data refers to $^{90}Sr$ and $^{137}Cs$, but occasionally the concentrations of $^{89}Sr$ and $^{134}Cs$ in some Italian samples are also given. The main sources of man made radionuclides were the global fallout produced by the nuclear weapon tests and the Chernobyl accident. The respective contributions to the contamination of surface seawater around both countries are discussed.

A New Hybrid Method for Flow-Dominated Transport

  • Lee, Jung-Lyul
    • 한국해안해양공학회:학술대회논문집
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    • 한국해안해양공학회 1997년도 정기학술강연회 발표논문 초록집 Annual Meeting of Korean Society of Coastal and Ocean Engineers
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    • pp.110-115
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    • 1997
  • Recently, since one of the most important societal problems facing us today is the growing incidence of the contamination of coastal sea from variety of sources, several distinct numerical improvements have been made and applying the transport models to flow-dominated transport area. Application of Eulerian numerical models to the solution of sharp-front problems often results in oscillations, phase errors, peak depression, and/or numerical dispersion, unless very fine temporal and spatial steps are adopted. (omitted)

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