• 제목/요약/키워드: Artificial contamination

검색결과 127건 처리시간 0.021초

태안반도 기름 유출사고 이후 인근해안에 서식하는 굴(Crassostrea gigas) 간췌장 (digestive gland) 의 미세구조 변화에 관한 연구 (A study on the effects of an artificial oil-spill on the ultrastructural changes in the digestive glands of Crassostrea gigas)

  • 전제천;강세원;백문기;정지은;신윤경;박영제;한연수;이용석
    • 한국패류학회지
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    • 제27권1호
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    • pp.77-86
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    • 2011
  • The unwanted artificial oil-spill has severely contaminated the coastal environment in the world. Level of contamination has so far been monitered by various indicator species including mussel, oysters, flounder, and cockle. In this study, we decided to use the oyster as a model organism to observe the morphological changes being exposed to the artificial oil-spill in the coastal areas in Taean, Korea. The oysters were collected from four local sites (Sindu-ri, Uiwang-ri, Jonghyeon-dong, Ansan and Uihang-ri) exposed to various levels of pollution after an oil spill in Taean. Microscopic analysis of the hepatopancreatic microstructure in the digestive gland from the collected oysters show that the swelling, whorl, and destruction phenomenon of the nuclear membrane, a well-known microstructure induced by heavy metal exposure, was observed. Nuclear body (Nb), another typical characteristic of contamination or infection were also observed in some samples. Necrosis was observed in tissue samples collected from the area with a high degree of oil pollution. In addition, parasite-like particles (virus, perkinsus) were observed in most samples. Taken together, these results suggest that oil contamination in the oyster habitats influences the cytopathological changes in Crassostrea gigas.

오손도 자동측정장치 개발을 위한 기초연구 (A Fundamental Investigation to Develope a Automatic Apparatus for Contamination Measurement)

  • 최남호;한상옥
    • 조명전기설비학회논문지
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    • 제15권3호
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    • pp.74-82
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    • 2001
  • 유지·보수를 위한 비용과 선로의 안정성과 신뢰성을 저해하는 정전 등의 사고를 감소시키기 위해서는 오손정도에 대한 정확한 측정이 선행되어야만 한다. 그러나, IEC 60815 등을 통해 추천되어 많은 연구에 있어 사용되어 온 수동 필세법은 인력, 비용, 측정오차 등의 측면에 있어 많은 문제점을 지니고 있다. 이에 본 연구에서는 옥외 환경에서 사용되는 애자표면의 오손정도를 측정할 수 있는 새로운 형태의 자동측정장치의 개발을 목적으로 한 일련의 연구를 수행하고자 한다. 장비의 설계 및 평가를 위해 FLUX 2D를 이용한 시뮬레이션과 인공오손과 관련한 다양한 실험을 수행하였다. 이와 같은 노력의 결과, 새로운 형태의 오손도 자동측정장치의 개발에 있어 중요한 것으로 사려되는 몇몇 결론을 얻을 수 있었다.

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배초향 추출액을 이용한 염색포의 염색성 및 항균성 (The Dyeing Properties and Antibiosis of Fabrics Dyed with Agastache rugosa Extract)

  • 박영희
    • 패션비즈니스
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    • 제16권1호
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    • pp.16-25
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    • 2012
  • As the test results for surface color, dyeing durability, antibiosis of cotton fabrics and silk fabrics dyed with Agastache rugosa extract, the following conclusions were obtained. The surface color of all the dyed fabrics was confirmed mostly as a GY system. As the result of chrominance(${\Delta}E_{ab}$) measurement, in the case of cotton fabrics the dyed fabrics treated with $Al_2(SO_4)_3$ mordant showed the highest value and in the case of silk fabrics the non-mordant dyed fabrics showed the highest value. The dyeing durability of test fabrics dyed with Agastache rugosa extract are as follows. As the test results of colorfastness to laundry for cotton dyed fabrics, the discoloration degree showed 1st-2nd grade and the contamination degree showed 4th-5th grade. As the test result of colorfastness to dry cleaning for silk dyed fabrics, the contamination degree showed from 1st to 3rd-4th grade. As the test results of colorfastness to acid artificial perspiration, the discoloration degree showed from 1st to 3rd-4th grade and the contamination degree showed from 3rd to 4th-5th grade. As the test results of colorfastness to alkaline artificial perspiration, the discoloration degree showed from 1st to 4th grade and the contamination degree showed from 3rd to 4th-5th grade. The colorfastness to sunlight showed from 1st to 2nd grade. The colorfastness to rubbing showed from 3rd to 4th-5th grade in dry process and from 2nd-3rd to 4th-5th grade in wet process. As the test results of antibiosis, the decrease rate of germs to virus Klebsiella pneumoniae and Staphylococcus aureus showed at least more than 99% after the wash of 10 times. As the test results of antifungal activity to mycete Trichophyton mentagrophytes and Aspergillus niger, the both cotton and silk dyed fabrics didn't gain the significant antifungal effect.

Bacterial Community Structure and the Dominant Species in Imported Pollens for Artificial Pollination

  • Kim, Su-Hyeon;Do, Heeil;Cho, Gyeongjun;Kim, Da-Ran;Kwak, Youn-Sig
    • The Plant Pathology Journal
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    • 제37권3호
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    • pp.299-306
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    • 2021
  • Pollination is an essential process for plants to carry on their generation. Pollination is carried out in various ways depending on the type of plant species. Among them, pollination by insect pollinator accounts for the most common. However, these pollinators have be decreasing in population density due to environmental factors. Therefore, use of artificial pollination is increasing. However, there is a lack of information on microorganisms present in the artificial pollens. We showed the composition of bacteria structure present in the artificial pollens of apple, kiwifruit, peach and pear, and contamination of high-risk pathogens was investigated. Acidovorax spp., Pantoea spp., Erwinia spp., Pseudomonas spp., and Xanthomonas spp., which are classified as potential high-risk pathogens, have been identified in imported pollens. This study presented the pollen-associated bacterial community structure, and the results are expected to be foundation for strengthening biosecurity in orchard industry.

옥외에서 사용되는 배전급 폴리머 현수애자의 오손특성에 관한 연구

  • 이병성;한상옥
    • 대한전기학회논문지:전기물성ㆍ응용부문C
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    • 제50권7호
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    • pp.340-345
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    • 2001
  • Because they have superior insulating properties and lower in price than their ceramic equivalents, polymeric insulators have been used in outdoor insulators. But polymeric insulators mainly using in an heavy contamination area of outdoor could be easily attached to contaminants such as salt and by-products of industrial processes. To understand its effect on contaminants adhered to these insulators, we dismounted polymeric insulators adhered contaminant in the field, and evaluated its electrical characteristics, CA, and ESDD. We also manufactured slurry mixed by some kaolin and salt for the artificial contamination test and measured the degree of contaminant, AC leakage current for these contaminated samples. Consequently, the adhered contaminants to its surface is likely to be affected the performance of insulation.

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송전용 현수애자의 인공오손 평가 (Evaluation of Artificially Contaminated Suspension Insulators for Transmission)

  • 김찬영;최인혁;홍동석;김범수
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2002년도 제4회 영호남학술대회 논문집
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    • pp.123-127
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    • 2002
  • This paper presented the results of evaluation of artificially contaminated suspension insulators for transmission lines. The suspension insulators were contaminated with kaolin and clay which were included various amount of natural salt. The degree of contamination were evaluated by measuring equivalent salt deposit density(ESDD). Then, the leakage currents were measured as a function of applied voltage, degree of contamination, humidity.

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LDPE에서 부시형 전기트리의 성장에 수반되는 부분방전 펄스의 특성 (Properties of PD Pulses accompanying with propagation of Bush-type tree in LDPE)

  • 박영국;강성화;정수현;박철현;임기조
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 1998년도 춘계학술대회 논문집
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    • pp.293-296
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    • 1998
  • Surface electrical conduction in insulator is most important factor to assess the insulation performances of outdoor insulating materials. In this paper, contamination performance of the widely used materials for outdoor insulator - porcelain, EPDM, Silicone rubber - were discussed by measuring properties of average leakage current and scintillation discharge pulses under artificial contamination conditions. The artificial contaminations used were deionized distilled water fog, 0.5wt% NaCl salt fog of light pollution and 2wt% NaCl salt fog of medium pollution. The average leakage current was appeared linearly with applied voltage at dry and clean surface condition. The magnitude of leakage current was almost same at different kinds of samples. In case of deionized distilled water fog, the characteristics of leakage current and applied voltage was most different to that in case of dry and clean condition. In case of salt fog pollution condition, The leakage current was increased above critical voltage. The scintillation discharges were also activated at the level. the leakage current and scintillation discharges were increased with increasing pollution degree. The resistance to pollution properties of silicone rubber appeared excellent among them.

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시화호의 중금속 오염과 산화-환원 상태의 공간적 차이 (Heavy Metal Contamination and Spatial Differences in Redox Condition of the Artificial Shihwa lake, Korea)

  • 현상민;김은수;팽우현
    • 한국환경과학회지
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    • 제13권5호
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    • pp.479-488
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    • 2004
  • Five sediment cores from the tidal flat of artificial Lake Shihwa are analyzed in terms of sedimentology and geochemistry to evaluate the heavy metal contamination and redox condition of surficial sediment following the Shihwa seawall construction. The variability of concentrations of various elements depends on the depositional environment, and reflects the various redox conditions and sediment provenances. The amounts of Ti and Al and their ratio of Ti/ Al with respect to Li clearly indicate that there is an anthropogenic contribution to the surficial sediment. The high concentrations of heavy metals suggest an anthropogenic contribution at ST. 34 and ST. 22. Concentrations of most elements (Cr, Cu, Zn and Pb) are higher near the Shihwa-Banwol industrial complex than in the central part of Lake Shihwa. Concentrations of heavy metal in surficial sediment near the Shihwa-Banwol industrial complex are two to eight times higher than in the center of Lake Shihwa. Enrichment factors (EF), which are normalized by the unpolluted shale, suggests a significant metallic contamination near the Shihwa-Banwol industrial complex (SBIC). The redox condition is divided into two anoxic and mixed oxi $c_oxic zones based on the carbon:sulfur (C/S) ratios of organic matter and elemental relationships. Correlations among geochemical elements Mn, U and Mo are significantly different from site to site, and may therefore be an indicator of the spatial redox condition. Controlling factors for switching anoxic/oxic conditions are thought to be water depth and the differences in industrial effluent supply. The variations of the Cu/Mn ratio in the sediments confirms above mentioned spatial differences of a redox condition in part, and therefore shows a location-dependence redox condition in sediments at four other sites. The redox condition of the surficial sediment characteristics of the Shihwa Lake are controlled by its geographic location and water depth.th.

인공타액오염이 유치 상아질에서 3종 상아질 접착제의 결합 강도에 미치는 영향 (Effects of Artificial Saliva Contamination on the Bond Strength of Three Dentin Adhesives to Dentin of Primary Teeth)

  • 배영은;김신;정태성;김지연
    • 대한소아치과학회지
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    • 제44권1호
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    • pp.72-81
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    • 2017
  • 본 연구의 목적은 유치 상아질의 복합레진 술식에서 각 단계별로 치면에 인공타액이 오염되었을 때와 이것을 제거하는 방법이 한 단계 자가부식 접착제와 두 단계 산 부식 접착제의 결합강도에 미치는 영향을 비교 분석하는 것이다. 연구 목적을 달성하기 위해, 건전한 유구치 42개를 선정하여 세 종류의 상아질 접착제인 Scotchbond Universal Adhesive(SBU), All-Bond Universal(ABU)과 Prime & Bond NT(PNT)에 따라 3개의 군으로 분류하였다. 이를 다시 각 접착제에서 7개의 하위 그룹으로 나누었다. 대조군인 1군을 제외한 나머지 군은 인공타액으로 오염시킨 군으로 다음과 같이 분류하였다: 2, 3군 - 접착제 도포 전; 4, 5군 - 접착제 중합 전; 6, 7군 - 접착제 중합 후. 인공타액은 수세, 건조(2, 4, 6군)와 건조(3, 5, 7군)로 제거하였다. 처치된 치면에 복합레진(Filtek, Z-350)으로 수복하고 시편을 제작한 후 미세인장 결합강도(Microtensile bond strength, MTBS)를 측정하였다. One-way ANOVA와 Tukey HSD test를 이용해서 통계분석을 실시하였다(p < 0.05). 대조군에서 MTBS의 평균값은 PNT가 ABU와 SBU에 비해 높게 나타났다(p < 0.001). 세 가지 접착제의 각 오염단계에서 수세와 건조를 시행했을 때(2, 4, 6군)가 건조만 시행했을 때(3, 5, 7군)보다 높은 결합강도를 나타내었다. 그리고 접착제 중합 전 단계에서 인공타액의 오염이 발생했을 때(4, 5군)는 대조군에 비해 낮은 MTBS를 보였다(p < 0.001). 전반적으로 두 단계 산 부식 접착제가 한 단계 자가부식 접착제에 비해 높은 MTBS를 보였다. 접착제를 중합하기 전 단계에서 인공타액에 오염되었을 경우에는 접착 강도가 현저히 감소하였고, 수세와 건조 과정으로 접착강도를 회복할 수 없었다.

인공지능 윤리 인식에 대한 데이터 분석 및 시각화 연구 -대화형 인공지능 서비스 '이루다'를 중심으로- (A Data Analysis and Visualization of AI Ethics -Focusing on the interactive AI service 'Lee Luda'-)

  • 이수련;최은정
    • 디지털융복합연구
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    • 제20권2호
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    • pp.269-275
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    • 2022
  • 사람을 대상으로 하는 인공지능 서비스가 증가하면서 인공지능에서도 윤리적 토대 위에서 이루어져야 한다는 사회적 요구가 증가하고 있다. 이러한 흐름에 따라 정부와 기업에서는 인공지능 윤리와 관련된 정책, 규범 등을 마련하고 있다. 합리적인 정책, 규범을 마련하기 위해서는 대중들이 가지고 있는 인식을 파악하는 것이 첫 번째 단계이다. 본 논문에서는 인공지능과 윤리에 대한 대중들의 인식을 파악하기 위해 소셜데이터와 뉴스 댓글을 수집하고 관심도 분석, 감성 분석, 담론 분석 수행 후 시각화하였다. 분석 결과, "인공지능 윤리"에 대한 관심도와 '인공지능" 호감도는 반비례하는 상관관계를 보여주었다. 담론분석 결과로, 가장 큰 이슈가 "개인정보 유출"이었고 학습 데이터의 오염 및 편향 문제와 컴퓨터로 만들어진 인공지능에게 법인격을 부여해야 하는지에 대한 담론도 보여주었다. 본 연구가 인공지능 윤리 규범, 정책을 마련할 때 대중들의 인식을 파악할 수 있는 자료로 활용될 수 있을 것이다.