• Title/Summary/Keyword: rapid visual screening

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Pre-earthquake fuzzy logic and neural network based rapid visual screening of buildings

  • Moseley, V.J.;Dritsos, S.E.;Kolaksis, D.L.
    • Structural Engineering and Mechanics
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    • v.27 no.1
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    • pp.77-97
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    • 2007
  • When assessing buildings that may collapse during a large earthquake, conventional rapid visual screening procedures generally provide good results when identifying buildings for further investigation. Unfortunately, their accuracy at identify buildings at risk is not so good. In addition, there appears to be little room for improvement. This paper investigates an alternative screening procedure based on fuzzy logic and artificial neural networks. Two databases of buildings damaged during the Athens earthquake of 1999 are used for training purposes. Extremely good results are obtained from one database and not so good results are obtained from the second database. This finding illustrates the importance of specifically collecting data tailored to the requirements of the fuzzy logic based rapid visual screening procedure. In general, results demonstrate that the trained fuzzy logic based rapid visual screening procedure represents a marked improvement when identifying buildings at risk. In particular, when smaller percentages of the buildings with high damage scores are extracted for further investigation, the proposed fuzzy screening procedure becomes more efficient. This paper shows that the proposed procedure has a significant optimisation potential, is worth pursuing and, to this end, a strategy that outlines the future development of the fuzzy logic based rapid visual screening procedure is proposed.

Terror Risk Analysis of High-rise Building by Rapid Visual Screening (Rapid Visual Screening을 통한 국내 고층건물의 테러 위험도 분석)

  • Ji, Jung-Hwan;Yoon, Sung-Won
    • Journal of Korean Association for Spatial Structures
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    • v.11 no.2
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    • pp.55-62
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    • 2011
  • While frequency of occurrence of terrorism has recently increased, it intensively occurs in buildings that many unspecified persons gather. Terrorism which occurs in high-rise buildings causes a lot of damage. It is necessary for design approach to reduce terrorism damage from explosive of buildings. Terror risk analysis of domestic tall and high-rise buildings is evaluated by fema 455, Rapid Visual Screening which is found to be comparatively simple and practicable. Common risk factors of terrorism in domestic buildings were investigated. The results of terror risk assessment of all buildings are found to be a medium risk score, Main reason is that domestic tall or high-rise buildings have similar external-environmental factors.

A Comparative Analysis of Terrorism Threat Level of Domestic Tall Buildings and General Buildings through Rapid Visual Screening (Rapid Visual Screening통한 건물 높이별 테러위험도 비교 분석)

  • Song, Jin-Young;Yoon, Sung-Won
    • Journal of Korean Association for Spatial Structures
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    • v.11 no.4
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    • pp.89-99
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    • 2011
  • As the scope of the target of terrorism is recently extending, the danger of domestic terroristic attacks is increasing constantly, and the form of terrorism is changing from hard targets such as significant facilities of the country into soft target of multi-complex buildings such as skyscrapers. Accordingly this study analyzes the terrorism threat level on skyscrapers by comparing the assessment results of the terrorism threat level on skyscrapers and high-rise buildings with the assessment results of the terrorism threat level on low-rise buildings through fema 455 - Rapid Visual Screening. As a result, skyscrapers and high-rise buildings are relatively higher threat rating than consequences and vulnerability rating. This is caused by the fact that the terrorism threat level on skyscrapers is high due to their residents and their national or regional symbolism and visibility

Analysis on the Risk of Explosive Terror in Domestic Buildings (국내 건물의 폭발물 테러 위험도 요인 분석)

  • Song, Jin-Young;Yoon, Sung-Won
    • Journal of Korean Association for Spatial Structures
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    • v.12 no.2
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    • pp.73-80
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    • 2012
  • According to the global status of terroristic acts occurred from 2002 to 2010, 10,431(nearly 52.2%) of 19,946 cases have happened by bomb blasts, and 10,431(nearly 52.2%) of weapons used for terrorism were explosive substances Therefore, this study analyzed the terrorism risks of buildings according to height through FEMA 455 - rapid visual screening. As a result, the higher the building is, the higher the terror risk gets. It shows that total risk increases proportionally to buildings's height. In case of buildings over 100 meter high, the total risk is most affected by threat items. According to the risk of explosion associated with the scenario analysis, buildings over 100 meter high have high risks of Internal-Explosive.

Explosive-Terror Risk Curve by RVS (RVS에 의한 폭발물테러 위험도 곡선)

  • Do, Ki-Young;Yoon, Sung-Won
    • Journal of Korean Association for Spatial Structures
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    • v.13 no.3
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    • pp.57-64
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    • 2013
  • Since the terrorist attacks 9.11 in 2001, the public places such as subway, department stores or office buildings have become a target of terror in major public facilities. In this paper, for the prevention of terrorist attack in domestic building, the assessments of terror risk were conducted and their relationship with building heights was discussed through FEMA 455-Rapid Visual Screening(RVS). Explosive terror risk tends to increase rapidly with building heights(H<230m), showing the correlation coefficient between total risk and building heights(H<230m) is 0.93. In addition, The average of consequences is 8.47 and that of' threat is 8.95. Vulnerability is found to be 6.62 in average.

Risk Assessment of Tall Buildings in Korea by comparative study of Modified RVS and IRVS system (수정 RVS와 IRVS시스템의 비교분석을 통한 국내 고층건물 테러위험도 평가)

  • Yu, Young-Su;Yoon, Sung-Won;Ju, Young-Kyu
    • Journal of Korean Association for Spatial Structures
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    • v.12 no.4
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    • pp.91-98
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    • 2012
  • As the occurrence rate of terror and hazard is increasing throughout the world, GSA, DoD, and FEMA are proceeding a study about mitigating the damage of terror. Korea is no more a safe place from the terrorist's threat, so we need to make measures against them. In this study we developed modified RVS System by revising some items to adjust the system to the domestic condition and conducted a risk assessment on several tall buildings in Korea. By using IRVS system which is developed by DHS, we also carried out the risk assessment. Comparing the results between RVS with IRVS, we performed terror risk evaluation of tall buildings. Through risk assessment of several tall buildings, we analyzed key factors of each scenarios and suggested the mean value of each items, so we would like to help the counter-terrorism in the design phase.

Development of a Redox Dye-Based Rapid Colorimetric Assay for the Quantitation of Viability/Mortality of Pine Wilt Nematode

  • Han, Kyeongmin;Lee, Jaejoon;Shanmugam, Gnanendra;Lee, Sun Keun;Jeon, Junhyun
    • Journal of Microbiology and Biotechnology
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    • v.29 no.7
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    • pp.1117-1123
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    • 2019
  • Control of pine wilt disease, which is caused by pine wilt nematode Bursaphelenchus xylophilus, is heavily dependent on the use of chemicals such as abamectin. Although such chemicals are highly effective, demands for alternatives that are derived preferentially from natural sources, are increasing out of environmental concerns. One of the challenges to discovery of alternative control agents is lack of fast and efficient screening method that can be used in a high-throughput manner. Here we described the development of colorimetric assay for the rapid and accurate screening of candidate nematicidal compounds/biologics targeting B. xylophilus. Contrary to the conventional method, which relies on laborious visual inspection and counting of nematode population under microscope, our method utilizes a redox dye that changes its color in response to metabolic activity of nematode population in a given sample. In this work, we optimized parameters of our colorimetric assay including number of nematodes and amount of redox dye, and tested applicability of our assay for screening of chemicals and biologics. We demonstrated that our colorimetric assay can be applied to rapid and accurate quantification of nematode viability/mortality in a nematode population treated with candidate chemicals/biologics. Application of our method would facilitate high-throughput endeavors aiming at finding environment-friendly control agents for deadly disease of pine trees.

The Use of Guided Waves for Rapid Screening of Chemical Plant Pipework

  • Alleyne, D.N.;Pavlakovic, B.;Lowe, M.J.S.;Cawley, P.
    • Journal of the Korean Society for Nondestructive Testing
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    • v.22 no.6
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    • pp.589-598
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    • 2002
  • The safe operation of petrochemical plant requires screening of the pipework to ensure that there are no unacceptable levels of corrosion. Unfortunately, each plant has many thousands of metres of pipe, much of which is insulated or inaccessible. Conventional methods such as visual inspection and ultrasonic thickness gauging require access to each point of the pipe which is time consuming and very expensive to achieve. Extensional or torsional ultrasonic guided waves in the pipe wall provide an attractive solution to this problem because they can be excited at one location on the pipe and will propagate many metres along the pipe, returning echoes indicating the presence of corrosion or other pipe features. Guided Ultrasonics Ltd have now commercialised the technique and this paper describes the basis of the method, together with examples of practical test results and typical application areas.

Development of Immunochromatography Strip-Test Using Nanocolloidal Gold-Antibody Probe for the Rapid Detection of Aflatoxin B1 in Grain and Feed Samples

  • Shim, Won-Bo;Yang, Zheng-You;Kim, Jung-Sook;Kim, Ji-Young;Kang, Sung-Jo;Woo, Gun-Jo;Chung, Young-Chul;Eremin, Sergei A.;Chung, Duck-Hwa
    • Journal of Microbiology and Biotechnology
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    • v.17 no.10
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    • pp.1629-1637
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    • 2007
  • An immunochromatography (ICG) strip test using a nanocolloidal gold-antibody probe was developed and optimized for the rapid detection of aflatoxin B1 (AFB1). A monoclonal antibody specific to AFB1 was produced from the cloned hybridoma cell (AF78), coupled with nanocolloidal gold, and distributed on the conjugate pad of the ICG strip test. The visual detection limit of the ICG strip test was 0.5 ng/ml, and this method showed a cross-reaction to aflatoxin B2, G1, and G2. In total, 172 grain and feed samples were collected and analyzed by both the ICG strip test and HPLC. The results of the ICG strip test showed a good agreement with those obtained by HPLC. These results indicated that the ICG strip test has a potential use as a rapid and cost-effective screening tool for the determination of AFB1 in real samples and could be applied to the preliminary screening of mycotoxin in food and agricultural products, generating results within 15 min without complicated steps.