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음란 사이트 현황과 차단 방법에 대한 고찰 (A Survey of Internet Sexual Sites and Blocking Methods)

  • 정진성;조동욱
    • 한국콘텐츠학회:학술대회논문집
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    • 한국콘텐츠학회 2003년도 추계종합학술대회 논문집
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    • pp.474-480
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    • 2003
  • 인터넷 유해 사이트중 청소년들에게 가장 해악이 심한 것이 음란 사이트이다. 본 고에서는 이같은 음란사이트에 대한 현황, 배포방법, 내용과 차단책 등 음란사이트 전체에 대한 심도있는 고찰을 행하고자 한다. 이를 통해 음란 사이트에 대한 문제점을 심도있게 분석 및 다룸으로써 건전한 인터넷 문화 형성에 기여하고자 한다.

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용접작업시 유해물질 발생이 건강에 미치는 영향과 관리대책 (The management counterplan of health caused by harmful materials during the welding work)

  • 이경만;이철구
    • 대한용접접합학회:학술대회논문집
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    • 대한용접접합학회 2006년 추계학술발표대회 개요집
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    • pp.274-276
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    • 2006
  • This study was researched by measuring the amount how much a welder inhaled the major harmful metals such as Fe, Mn, Cu, Zn and so on which occurred at the welding site during welding work and also by measuring the heavy metal concentration in a welder's blood after the welding. By using the mobile fan, the measure of welding fume and the result were taken.

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통신회선의 잡음전압 기준 및 측정법 (Psophometeric Noise Voltage of Telecommunication Lines and Test methods)

  • 황종선;김영민;이경욱;김재준
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2001년도 추계학술대회 논문집 Vol.14 No.1
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    • pp.617-620
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    • 2001
  • The protection of communication lines against harmful effects from electricity lines is very important with the rapid development of communications network. This paper is introduced the reference of noise voltage and the test methods of foreign countries. Further we will also present study measurement equipment for telecommunications noise voltage and circuit noise phenomenon.

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Chemical Control of Weed for Flax

  • Kwon, Byung-Sun
    • Plant Resources
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    • 제7권2호
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    • pp.110-115
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    • 2004
  • This study was conducted to evaluate the effect of herbicides on weed control, growth characteristics and yield in flax, after direct seeding it to the field, the herbicides treated had no effect on the emergence period. The major weeds were decreased some what more with mecoprop-wp, herbicide than the other herbicides and by hand weeding. Mecoprop-wp and simazin-wp were had no injury but sethoxydim-EC and 2.4-D-wp were slighthy harmful for the flax with recommended concentration, On the other hand, all herbicides were harmful in the double dosage level

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통신회선의 잡음전압 기준 및 측정법 (Psophometeric Noise Voltage of Telecommunication Lines and Test methods)

  • 황종선;김영민;이경욱;김재준
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2001년도 추계학술대회 논문집
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    • pp.617-620
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    • 2001
  • The protection of communication lines against harmful effects from electricity lines is very important with the rapid development of communications network. This paper is introduced the reference of noise voltage and the test methods of foreign coutnreis. Further we will also present study measurement equipment for telecommunications noise voltage and circuit noise phenomenon.

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식품중(食品中) 유해성중금속(有害性重金屬)에 관(關)한 연구(硏究) ( I ) -콩나물중의 수은 정량- (Studies on the Harmful Heavy Metal of Food Stuff( I ) -Contents of Hg in edible Bean Sprouts-)

  • 박재홍;남현근
    • Journal of Nutrition and Health
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    • 제10권3호
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    • pp.7-9
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    • 1977
  • Quantitative analysis of harmful Hg in edible bean sprouts was carried out by the Atomic Absorption Spectrophotometer (Perkin-Elmer Model 403). The samples studied as shown in Table 2. are edible bean sprouts (36) which wet·e collected from Gwangju area. It was investigated that the Mercury (Hg) content of edible bean sprouts was from 0.0098 ppm to 0.533 ppm (average 0.240). Mercury contaminated edible bean sprouts studied, was about 50 percentage of total samples.

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Alexandrium catenella와 유해성 적조종에 대한 Arthrobacter sp. NH-3와 살조물질의 살조능 (The Algicidal Activity of Arthrobacter sp. NH-3 and its Algicide against Alexandrium catenella and other Harmful Algal Bloom Species)

  • 정성윤;정남호
    • 한국환경농학회지
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    • 제34권2호
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    • pp.139-148
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    • 2015
  • BACKGROUND: The aim of this study was to isolate and identify algicidal bacterium that tends to kill the toxic dinoflagellate Alexandrium catenella, and to determine the algicidal activity and algicidal range of algicide. METHODS AND RESULTS: Among of algicidal bacteria isolated in this study, NH-3 isolate was the strongest algicidal activity against A. catenella. NH-3 isolate was identified on the basis of biochemical characteristics and analysis of 16S rRNA gene sequences. The NH-3 isolate showed over 99% homology with Arthrobacter oxydans, and was designated as Arthrobacter sp. NH-3. The optimal culture conditions were $25^{\circ}C$, initial pH 7.0, and 2.0% (w/v) NaCl concentration. The algicidal activity of Arthrobacter sp. NH-3 was significantly increased to maximum value in the late of logarithmic phase. Arthrobacter sp. NH-3 showed algicidal activity through indirect attack, which excreted active substance into the culture filtrate. When 10% culture filtrate of NH-3 was applied to A. catenella, 100% of algal cells were destroyed within 30 h. In addition, the algicidal activities were increased in dose and time dependent manners. The pure algicide was isolated from the ethyl acetate extract of the culture filtrate of NH-3 by using silica gel column chromatography and high performance liquid chromatography (HPLC). We investigated the algicidal activity of this algicide on the growth of harmful algal bloom (HAB) species, including A. catenella. As a result, it showed algicidal activity against several HAB species at a concentration of $100{\mu}g/mL$ and had a relatively wide host range. CONCLUSION: Taken together, our results suggest that Arthrobacter sp. NH-3 and its algicide could be a candidate for controlling of toxic and harmful algal blooms.

남녀 대학생들의 방사선 인식 정도에 관한 비교 연구 (A Comparative Study on the Radiation Awareness of University Students Gender in Chungbuk Area)

  • 장재선;황성희
    • 한국식품영양학회지
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    • 제28권3호
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    • pp.486-492
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    • 2015
  • This study was conducted to provide fundamental data on the awareness of radiation, specifically the differences between general awareness, psychological state and harmful effects. Data was collected from 334 University students in the Chungbuk region through a self-administered questionnaire. According to the results of the reliability and factor analysis, the awareness of radiation was 2.80, with a Cronbach alpha coefficient of 0.815 and KMO of 0.798. Factor analysis extracted three components of the awareness of radiation, which we named general awareness (factor 1), psychological state (factor 2), and harmful effect (factor 3). There were significant differences in the general awareness of natural radiation and radiation-containing foods (p<0.05), whereas no significant differences were found in the general awareness of radiation food supply (p>0.05). Also, the psychological state showed a significant difference in exposure inspection, future exposure, and radiation-containing food (p<0.05), whereas no significant differences were found in the refusal of radiation inspection (p>0.05). The harmful effects showed a significant difference in the rejection of radiation (p<0.05), but no significant differences in the cancer and genetic effects, diseases and physical harmfulness (p>0.05). A significant positive result (p<0.05) was found for the psychological state according to the harmful effects of radiation. Based on this study, detailed and continuous education must be accomplished by increasing the awareness of radiation and the acceptance level, conveying a proper understanding of radiation and assisting subjects with receiving the information they desire through various educational mediums.

Methods for sampling and analysis of marine microalgae in ship ballast tanks: a case study from Tampa Bay, Florida, USA

  • Garrett, Matthew J.;Wolny, Jennifer L.;Williams, B. James;Dirks, Michael D.;Brame, Julie A.;Richardson, R. William
    • ALGAE
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    • 제26권2호
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    • pp.181-192
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    • 2011
  • Ballasting and deballasting of shipping vessels in foreign ports have been reported worldwide as a vector of introduction of non-native aquatic plants and animals. Recently, attention has turned to ballast water as a factor in the global increase of harmful algal blooms (HABs). Many species of microalgae, including harmful dinoflagellate species, can remain viable for months in dormant benthic stages (cysts) in ballast sediments. Over a period of four years, we surveyed ballast water and sediment of ships docked in two ports of Tampa Bay, Florida, USA. Sampling conditions encountered while sampling ballast water and sediments were vastly different between vessels. Since no single sample collection protocol could be applied, existing methods for sampling ballast were modified and new methods created to reduce time and labor necessary for the collection of high-quality, qualitative samples. Five methods were refined or developed, including one that allowed for a directed intake of water and sediments. From 63 samples, 1,633 dinoflagellate cysts and cyst-like cells were recovered. A native, cyst-forming, harmful dinoflagellate, Alexandrium balechii (Steidinger) F. J. R. Taylor, was collected, isolated, and cultured from the same vessel six months apart, indicating that ships exchanging ballast water in Tampa Bay have the potential to transport HAB species to other ports with similar ecologies, exposing them to non-native, potentially toxic blooms.