• Title/Summary/Keyword: media exposure

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Accelerated SCC Testing of Stainless Steels According to Corrosion Resistance Classes

  • Borchert, M.;Mori, G.;Bischof, M.;Tomandl, A.
    • Corrosion Science and Technology
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    • v.14 no.6
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    • pp.280-287
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    • 2015
  • The German Guidelines for stainless steel in buildings (Z.30.3-6) issued by the German Institute for Building Technology (DIBt) categorizevarious stainless steel grades into five corrosion resistance classes (CRCs). Only 21 frequently used grades are approved and assigned to these CRCs. To assign new or less commonly used materials, a large program of outdoor exposure tests and laboratory tests is required. The present paper shows theresults of stress corrosion cracking (SCC) tests that can distinguish between different CRCs. Slow strain rate tests (SSRT) were performedin various media and at different temperatures. CRC IV could be distinguished from CRC II and CRC III with a 31.3 % $Cl^-$ as $MgCl_2$ solutionat $140^{\circ}C$. CRC II and CRC III could be differentiated by testing in a 30% $Cl^-$ as $MgCl_2$ solutionat $100^{\circ}C$.

Deterioration of Cement Matrix with Alkali-free Accelerator Exposed to Sulfate Media (황산염환경에 노출된 알카리프리계 급결제 사용 시멘트경화체의 성능저하)

  • Lee, Seung-Tae;Hooton, R.D.;Kim, Seong-Soo;Kim, Dong-Gyou
    • Proceedings of the Korea Concrete Institute Conference
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    • 2006.05b
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    • pp.277-280
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    • 2006
  • This paper presents the findings on the sulfate resistance of mortar specimens with or without alkali-free accelerator exposed to sodium sulfate solution for 270 days. Test results confirms a negative effect of alkali-free accelerator on the sulfate deterioration. Additionally, the influences of exposure concentration and temperature of sulfate solution on expansion were investigated. Especially, at a high concentration of solution a significant expansion of mortar specimens with alkali-free accelerator was observed. Further, low temperature also promoted the deterioration of the cement system due to sulfate attack.

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토양 오염물질의 독성 탐지를 위해 유전자 재조합 발광 박테리아를 이용한 환경 바이오 센서의 개발과 응용

  • Jang, Seok-Tae;Lee, Hyeon-Ju;Gu, Man-Bok
    • 한국생물공학회:학술대회논문집
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    • 2000.11a
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    • pp.212-215
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    • 2000
  • Recombinant bioluminescent bacterial strains that use specific promoters fused to the bioluminescence genes (lux genes) have been applied in environmental monitoring. Advantages of using recombinant bioluminescent bacteria as blosensing cells include rapid responses, low costs, and improved reproducibility. In this study, a recombinant Escherichia coli, GC2, containing a lac::luxCDABE fusion immobilized with solid agar media and glass beads was used to estimate the effect of this soil flushing technique. This bacterium constitutively emits light under normal conditions (no toxic chemicals). When growth and metabolism of these bioluminescent bacteria is inhibited by their exposure to toxic chemicals, the bioluminescence (BL) is reduced. A biosurfactant, rhamnolipids, was used to extract phenanthrene from the soil after flushing.

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Advanced Auto-Focus and Auto-Exposure Algorithm Detecting Object for Video Camera (피사체 인식을 이용한 비디오 카메라용 자동 초점 및 자동 노출 알고리즘)

  • Lee, Kwang-Hyun;Lee, Sang-Hoon
    • Proceedings of the Korean Society of Broadcast Engineers Conference
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    • 2008.02a
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    • pp.147-150
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    • 2008
  • 현재의 비디오 카메라는 인간의 눈으로 볼 수 있는 것과 동일한 화질의 비디오 영상을 얻을 수 없다. 인간의 눈은 움직이는 물체에 중점을 두고 초점을 맞추는 시각적 특성을 가진다. 하지만 현재의 비디오 카메라 시스템은 영상에 대한 인간의 눈의 시각적 특성에 대한 고려 없이 조리개와 렌즈의 조절 작업이 이루어진다. 본 논문은 이러한 비디오 카메라 시스템의 개선을 위해 인간의 눈의 시각적 특성에 기반을 둔 실시간 피사체 적응 비디오 카메라 시스템을 제안한다. 제안하는 알고리즘은 영상내에서 움직임을 가진 물체를 찾아낸 뒤, 이것에 가중치를 두고 조리개와 초점제어 작업의 순서로 이루어진다. 움직이는 물체는 영상 코덱의 움직임 정보를 파악하여 찾아내었다. 제안된 알고리즘은 프로그램언어로 구현되었으며, 초점거리와 조리개제어가 가능한 카메라와 PC를 사용하여 영상을 분석, 검증하였다.

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Materials and Systems for Noise Control : Categorization and Challenges

  • Bolton, J. Stuart
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2010.05a
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    • pp.44-44
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    • 2010
  • In this presentation, noise control materials will be discussed from several points-of-view. First, materials will be categorized in terms of their intended function: i.e., as dissipative materials, as barriers, and as media intended to modify some aspect of the sound field. Within each category, example implementations will be described as will modeling procedures. In the context of barrier materials, recent developments in the area of metamaterials will be described briefly, and problems with some recently suggested approaches will be highlighted. Acoustical cloaking will be described as a method of modifying a sound field in such a way that a sensitive area is shielded from noise exposure; the practical difficulties of this approach will also be described. Finally, within each category of material and approach, a series of suggested research challenges will be described.

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Scientific Management Policy for Hazardous Substances (유해물질 관리정책의 과학화)

  • Jung, Ki-Hwa
    • Journal of Food Hygiene and Safety
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    • v.26 no.2
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    • pp.171-181
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    • 2011
  • Though food safety efforts of the government has been increasing, but the health hazards resulting from food does not stop and thus increases consumers' anxiety and distrust of government. For more reliable safety management, developing analysis and intake measurement methods and strengthening regulatory control with strict criteria is necessary. In addition, as not only the known hazards by now, but also unknown but obvious hazards are simultaneously ongoing in current environments, the unified risk management and health assessment for food, health food and medicines from the media is critical. As risks and damage to health may show up after a long time after exposure, preventive measures and strategies for safety control is also needed.

Non-uniform Deblur using Gyro sensor and long/short exposure image pair (자이로 센서와 노출시간이 다른 두 장의 영상을 이용한 불균일 디블러)

  • Ryu, Ho Hyoung;Song, Byung Cheol
    • Proceedings of the Korean Society of Broadcast Engineers Conference
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    • 2015.07a
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    • pp.540-541
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    • 2015
  • 본 논문은 카메라 촬영 시 손 떨림 등에 의해 생기는 불균일한 블러 현상에 대해 영상 IMU 센서와 노출시간이 긴 영상과 짧은 영상 쌍을 이용한 디블러 알고리즘을 제안한다. 먼저 IMU 센서로부터 얻어진 gyro 데이터로 초기 커널을 추정한다. 그런 다음 노출시간이 다른 영상 쌍에 Lucas-Kanade 기법을 적용하여 상기 추정된 초기 커널을 개선한다. 이렇게 구해진 커널에 기반하여 residual deconvolution 을 수행 디블러 영상을 생성한다. 실험 결과로부터 제안 알고리즘이 기존 기법에 비해 우수한 성능을 보임을 알 수 있다.

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PSYCHOLOGICAL EVALUATION AND THE APPLICABILITY OF THE IMPRESSION TRANSFER VECTOR METHOD FOR SYNTHESIZING HIGHER-ORDER FACIAL IMPRESSIONS

  • Sakuta, Yuiko;Ishi, Hanae;Akamatsu, Shigeru;Gyoba, Jiro
    • Proceedings of the Korean Society of Broadcast Engineers Conference
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    • 2009.01a
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    • pp.689-694
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    • 2009
  • We developed a facial image generating technique that can manipulate facial impressions. The present study applied this impression transferring method to higher-order impressions such as "elegance" or "attractiveness" and confirmed the psychological validity of this method using the semantic differential method. Subsequently, we applied this method to two types of cognitive experiments. First, we examined the contributions of texture and shape on the facial impressions by using those face images for which the impressions have already been quantitatively manipulated based on this method. Second, we used such stimuli to examine the effect of facial impressions and attractiveness on the "mere exposure effect." Thus, we concluded that the impression transfer vector method is an effective tool to quantitatively manipulate the facial impressions in various cognitive studies.

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Verification of AGB (alpha-glucosidase biosynthesis) Bacterial Bioassay of Metal Toxicity and Inhibition Effect of Fulvic Acid (EA) (박테리아(E. Coli)의 AGB (alpha-glucosidase biosynthesis)를 이용한 중금속의 독성시험과 풀빅산에 의한 독성 억제효과)

  • Kim Jae Hyoun;Kim Myung Gill;Om Ae Son
    • Environmental Analysis Health and Toxicology
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    • v.19 no.1
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    • pp.25-32
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    • 2004
  • Aim of the present study was the development of a bioassay which enables the detection of toxic effects of heavy metal ions to a bacterium, Escherichia coli. Inhibition effects of the metals on growth rates of the bacterium were studied in the absence or presence of fulvic acid. This method does not clearly differentiate among metals, but does detect overall AGB inhibition rate (toxicity) for 5 different heavy metals. The toxicity of the metals in the absence of fulvic acid in the same testing conditions was significantly increased in following order: Hg < Pb, Zn < Cd < Cu, whereas the inhibition rate (toxicity) in the presence of FA was shown to be increased In following order: Cd < Pb, Hg < Cu < Zn. The results of the present study indicate that this simple and fast biomonitoring assay with direct exposure of E coli. might be a valuable supplement to analytical methods of contaminated media.

Study on the Effect of Vitamin E on Cultured Hippocampal Neurons Damaged by Hydrogen Peroxide (과산화수소로 손상된 배양 해마신경세포에 대한 Vitamin E의 영향에 관한 연구)

  • Lee Jung Hun;Lee Joung Hwa;Cho Nam Su
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.17 no.2
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    • pp.447-450
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    • 2003
  • To clerify the cytotoxicity of reactive oxygen species in cultured hippocampal neurons of neonatal mouse, toxic effect was measured by MTT assay after cultured cells were incubated for 3 hours in the media containing 1~40 μM concentrations of H₂O₂. In addition, the protective effect of vitamin E was determined in these cultrures. Cell viability was significantly decreased in a dose-dependent manner after exposure of 10 μM H₂O₂ to cultured mouse hippocampal neurons for 5 hours. In the protective effect of vitamin E, vitamin E prevented the H₂O₂-induced cytotoxicity in these cultures. From these results, it suggests that H₂O₂ has toxic effect in cultured mouse hippocampal neurons and vitamin E has protective effect on the cytotoxicity induced by H₂O₂.