• Title/Summary/Keyword: Artificial contamination

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

  • Jun, Je-Cheon;Kang, Se-Won;Baek, Moon-Ki;Jeong, Ji-Eun;Shin, Yun-Kyung;Park, Young-Je;Han, Yeon-Soo;Lee, Yong-Seok
    • The Korean Journal of Malacology
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    • v.27 no.1
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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.

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

  • 최남호;한상옥
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.15 no.3
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    • pp.74-82
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    • 2001
  • To reduce the maintenance expense and the possibility of electric outage and/or accident, which causes the decrease in stability and reliability of transmission/distribution line, most of all, accurate measurement for the degree of contamination should be preceded. But the conventional method (brush wiping method), which is recommended in IEC 60815, has sow significant problem in the aspect of man power, expense, error, and so forth. In this investigation, we purpose the development of a new type automatic measuring apparatus, which could measure the degree of contamination on the surface of insulator in outdoor condition. To design and evaluate the apparatus, a FLUX 2D is used, and various laboratory tests, artificial contamination tests, were carried to proof the actual performance. With the result of these effort, we can get the meaningful conclusion to develope a new type automatic apparatus for contamination measurement.

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

  • Park, Young-Hee
    • Journal of Fashion Business
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    • v.16 no.1
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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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    • v.37 no.3
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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

  • Lee, Byung-Sung;Han, Sang-Ok
    • The Transactions of the Korean Institute of Electrical Engineers C
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    • v.50 no.7
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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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Evaluation of Artificially Contaminated Suspension Insulators for Transmission (송전용 현수애자의 인공오손 평가)

  • Kim, Chan Young;Choi, In-Hyuk;Hong, Dong-Suk;Kim, Beom-Soo
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2002.08a
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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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Properties of PD Pulses accompanying with propagation of Bush-type tree in LDPE (LDPE에서 부시형 전기트리의 성장에 수반되는 부분방전 펄스의 특성)

  • 박영국;강성화;정수현;박철현;임기조
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 1998.06a
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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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Heavy Metal Contamination and Spatial Differences in Redox Condition of the Artificial Shihwa lake, Korea (시화호의 중금속 오염과 산화-환원 상태의 공간적 차이)

  • Hyeon, Sang-Min;Kim, Eun-Su;Paeng, U-Hyeon
    • Journal of Environmental Science International
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    • v.13 no.5
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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.

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

  • Bae, Youngeun;Kim, Shin;Jeong, Teasung;Kim, Jiyeon
    • Journal of the korean academy of Pediatric Dentistry
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    • v.44 no.1
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    • pp.72-81
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    • 2017
  • The aim of this study was to evaluate the effectiveness of artificial saliva contamination and decontamination procedures at different stages of a bonding procedure on the microtensile bond strength (MTBS) of two one-step self-etch adhesives and a two-step total-etch adhesive to dentin of primary teeth. Forty-two extracted sound primary molars were randomly divided into three groups depending on three adhesives, Scotchbond Universal Adhesive (SBU), All-Bond Universal (ABU) and Prime & Bond NT (PNT). For each adhesive, the teeth were allocated into seven groups. Except for control group, group 1, the groups were contaminated with artificial saliva at three different stages: the groups 2 and 3 - before adhesive application; the groups 4 and 5 - before adhesive polymerization; the groups 6 and 7 - after adhesive polymerization. Decontaminating procedures were rinsing, air-drying (group 2, 4, 6) and air-drying (group 3, 5, 7). The specimens were restored with composite resin (Filtek, Z350) and microtensile bond strength was measured. The data was analyzed with one-way ANOVA and Tukey HSD test (p < 0.05). In the control group, using PNT resulted in significantly higher bond strength than when ABU and SBU were used (p < 0.001). For three adhesives, the groups 2, 4 and 6 had greater bond strength than the groups 3, 5 and 7. Also, when the artificial saliva was contaminated before adhesive polymerization (group 4, 5), it showed a significantly lower bond strength. Generally the two-step total-etch adhesive generated a higher bond strength than the one-step self-etch adhesive. Artificial saliva contamination before adhesive polymerization led to a drastic decrease in bond strength, and rinsing with water followed by air-drying could not recover the bond strength.

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

  • Lee, Su-Ryeon;Choi, Eun-Jung
    • Journal of Digital Convergence
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    • v.20 no.2
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    • pp.269-275
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    • 2022
  • As artificial intelligence services targeting humans increase, social demands are increasing that artificial intelligence should also be made on an ethical basis. Following this trend, the government and businesses are preparing policies and norms related to artificial intelligence ethics. In order to establish reasonable policies and norms, the first step is to understand the public's perceptions. In this paper, social data and news comments were collected and analyzed to understand the public's perception related to artificial intelligence and ethics. Interest analysis, emotional analysis, and discourse analysis were performed and visualized on the collected datasets. As a result of the analysis, interest in "artificial intelligence ethics" and "artificial intelligence" favorability showed an inversely proportional correlation. As a result of discourse analysis, the biggest issue was "personal information leakage," and it also showed a discourse on contamination and deflection of learning data and whether computer-made artificial intelligence should be given a legal personality. This study can be used as data to grasp the public's perception when preparing artificial intelligence ethical norms and policies.