• 제목/요약/키워드: Hazard material

검색결과 320건 처리시간 0.032초

고흡수성 수지와 기포콘크리트를 이용한 보수성포장용 보수재 성능 평가 (Evaluation of Characteristics of Water Retaining Material for Water Retaining Pavement using High Absorptiveness Resin and Foamed Concrete)

  • 이수형;유인균
    • 한국방재학회:학술대회논문집
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    • 한국방재학회 2008년도 정기총회 및 학술발표대회
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    • pp.321-324
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    • 2008
  • Water retaining pavement is a pavement to lower the surface temperature by using evaporation of the water that the pavement contains when the pavement is heated by the sun in the daytime, so, to improve performance, the performance can absorb water. Most of the high-performance material that absorbs water swell $2\sim3$ times as much volume when it contact with water. Water retaining material exists independently of the material in the cement. so it doesn't have the space to expand. Therefore, the performance of absorbing water is decreased. Therefore, this study was to develop a foamed concrete and evaluation of performance characteristics using high absorptiveness resin. The result has been evaluated as excellent compared to other materials.

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ADS-B장착 항공기 예비위험분석 (Preliminary Hazard Analysis for ADS-B equipped Aircraft)

  • 김용석;최영재;신대원
    • 한국항공운항학회지
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    • 제16권3호
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    • pp.58-63
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    • 2008
  • ICAO has recommended ADS-B implementation that is considered as next generation surveillance system to meet the air traffic capability and aviation safety. However, safety verification for the new ADS-B technology should be carried out in advance. FAA performed a preliminary hazard analysis for ADS-B equipped aircraft through Capstone program in Alaska in order to reduce aviation accidents. The present study deals with ADS-B concept, FAA Capstone program and PHA for ADS-B equipped aircraft. We expect that this paper will be a valuable material to assess ADS-B risk when it is applied to the domestic environment.

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화학공정 주변지역에 미치는 위험성(사회적 위험성 및 개인적 위험성) 평가방법에 관한 비교 연구 (A Comparative Study on the Risk(Individual and Societal) Assessment for Surrounding Areas of Chemical Processes)

  • 김윤화;엄성인;고재욱
    • 한국안전학회지
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    • 제10권1호
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    • pp.56-63
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    • 1995
  • Two methods of the numerical method of CPQRA(Chemical Process Quantitative Risk Analysis) and the manual method of IAEA(International Atomic Energy Agency) were used to estimate the individual risk and societal risk around the chemical plant. Where, the CPQRA is introduced to verify the theoritical background of the manual of international atomic energy agency. The Gaussian plume model which has a weather stability class D with velocity of 5m/s was applied to calculate dispersion of hazard material. Also, 8-point method was employed to the effects of accidents for wind distribution. Furthermore, historical record, FTA(Fault Tree Analysis) and ETA(Event Tree Analysis) were used to estimate the probability or frequency of accidents. Eventually, the individual risk shows isorisk contour and the societal risk shows F-N curve around hazard facility, especially in chemical plants. Caulculated results, which both individual and societal risk, by using IAEA manual show simillar results to those of calculation by numerical method of CPQRA.

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GEOTECHNICAL HAZARD REVIEW

  • Hencher, Steve
    • 대한지질공학회:학술대회논문집
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    • 대한지질공학회 2000년도 정기총회 및 학술발표회
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    • pp.3-18
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    • 2000
  • Engineering projects often run into "difficult" ground donditions which cause delays, failures, hugely increased costs or even abandonment with consequent disputes and claims. Pertinent questions are "what constitute difficult conditions\ulcorner" and "how might they be foreseen\ulcorner" and these questions provide the focus for this paper. Geological, geotechnical and hydrogeological models for engineering projects(simplified representations of the ground) need to be developed in a systematic manner. Within these models, the potential hazards associated with material (small) and mass (large) scale attributes of the geology, the environmental setting and the influence of the engineering works themselves need to be considered individually and in a progressive, systematic manner. This paper introduces the concept of a Geotechnical Hazard Review with reference to examples from various engineering works.

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Formulation of Dynamic Vehicle-Bridge Interaction Problems

  • Yi, Gyu-Sei
    • 한국방재학회 논문집
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    • 제2권4호
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    • pp.97-116
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    • 2002
  • In this papers, a finite element formulation is proposed for dynamic analysis of vehicle-bridge interaction problems under realistic loading conditions. Although the formulation presented in this paper is based on the consideration of only a single traversing vehicle, it can be extended to include several different bridge configurations. The traversing vehicle and the vibrating bridge superstructure are considered as an integrated system. Hence, although material and geometric nonlinearities are excluded, this introduces nonlinearity into the problem. Various vehicle models, including those with suspension systems, are considered. Traveling speed of the vehicle can be varied. The finite element discretization of the bridge structure permits the inclusion of arbitrary geometrical configurations, and surface and boundary conditions. To obtain accurate solutions, time integration of the equation of vehicle-bridge motion is carried out by using the Newmark method in connection with a predictor-corrector algorithm.

시뮬레이션 기법을 이용한 지진 시 사면안정 해석 (Simulation-Based Assessment of Seismic Slope Stability)

  • 김진만
    • 한국지진공학회:학술대회논문집
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    • 한국지진공학회 2003년도 춘계 학술발표회논문집
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    • pp.157-164
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    • 2003
  • A simulation-based approach that can be used to systematically model the uncertainties of seismic loading and geotechnical property is presented in the context of reliability analysis of slope stability. The uncertainty of seismic loading is studied by generating a large series of hazard-compatible artificial motions, and by using them in subsequent response analyses. The stochastic nature of spatially varying material properties and also the uncertainty arising from insufficient information are treated in the framework of random fields. The simulation-based analyses indicate that in a seismically less active region, a moderate variability in soil properties has a relatively large effect as much as characterization of earthquake hazard on the computed risk of slope failure and excessive slope deformations.

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Simplified nonlinear simulation for composite segmental lining of rectangular shield tunnels

  • Zhao, Huiling;Liu, Xian;Yuan, Yong
    • Structural Engineering and Mechanics
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    • 제81권4호
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    • pp.513-522
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    • 2022
  • Steel-concrete composite segments replacing the conventional reinforced concrete segments can provide the rectangular shield tunnel superiorities on bearing capacity, ductility and economy. A simplified model with high-efficiency on computation is proposed for investigating the nonlinear response of the rectangular tunnel lining composed of composite segments. The simulation model is developed by an assembly of nonlinear fiber beam elements and spring elements to express the transfer mechanism of forces through components of composite segments, and radial joints. The simulation is conducted with the considerations of material nonlinearity and geometric nonlinearity associated with the whole loading process. The validity of the model is evaluated through comparison of the proposed nonlinear simulation with results obtained from the full-scale test of the segmental tunnel lining. Furthermore, a parameter study is conducted by means of the simplified model. The results show that the stiffness of the radial joint at haunch of the ling and the thickness of inner steel plate of segments have remarkable influence on the behaviour of the lining.

UN GHS 기준에 의한 국내 건강.환경유해성 분류기준 및 분류결과의 통일화 방안 연구 (Study on the Harmonization of Health and Environmental Hazard Classification Criteria and Its Results Based on the UN GHS)

  • 이권섭;이종한;송세욱
    • 한국산업보건학회지
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    • 제22권2호
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    • pp.140-148
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    • 2012
  • Objectives: This study was performed to provide harmonized guidelines on health and environmental classification criteria and its results of chemicals in Korea. Methods: Firstly, The history of GHS implementation in UN and Korea was reviewed. Secondly, the differences in classification criteria on health and environmental hazards among UN GHS and two Korean government agencies, Korea Ministry of Employment and Labour (KMoEL) and Korea Ministry of Environmental (KMoE). The classification results were compared between classifications of Korea Occupational Safety and Health Agency (KOSHA) based on KMoEL and classifications of Korea National Institute of Environmental Research (KNIER) based on KMoE. Finally, an inter-agency harmonization on the classification criteria and the results was suggested by comparing the classification results of 5 chemicals; Benzene, carbon disulfide, formaldehyde, toluene-2,4-diisocyanate, and trichloroethylene. Results: KMoEL and KMoE revised regulations on chemical management and published a Notices on GHS classification criteria according to UN GHS document. However, the hazard to the ozone layer contained in the latest edition of UN GHS document published in 2011 was not included yet. The differences in classifications of 5 chemicals between KOSHA and KNIER were 36.2% in health hazards and 23.4% in environmental hazards, respectively. In conclusion, we suggested that a new revision be needed to include newly contained hazard and inter-agency working party be organized to harmonize classification results.

Safety Data Sheets as a Hazard Communication Tool: An Assessment of Suitability and Readability

  • Kevin Ho;Thomas Tenkate
    • Safety and Health at Work
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    • 제15권2호
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    • pp.192-199
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    • 2024
  • Background: Safety data sheets (SDSs) are hazard communication materials that accompany chemicals/hazardous products in the workplace. Many SDSs contain dense, technical text, which places considerable comprehension demands on workers, especially those with lower literacy skills. The goal of this study was to assess SDSs for readability, comprehensibility, and suitability (i.e., fit to the target audience). Methods: The Suitability Assessment of Materials (SAM) tool assessed SDSs for suitability and readability. We then amended the SAM tool to further assess SDSs for comprehensibility factors. Both the original and amended SAM tool were used to score 45 randomly selected SDSs for content, literacy demand, graphics, and layout/typography. Results: SDSs performed poorly in terms of readability, suitability, and comprehensibility. The mean readability scores were Flesch-Kincaid Grade Level (9.6), Gunning Fog index (11.0), Coleman-Liau index (13.7), and Simple Measure of Gobbledygook index (10.7), all above the recommended reading level. The original SAM graded SDSs as "not suitable" for suitability and readability. When the amended SAM was used, the mean total SAM score increased, but the SDSs were still considered "not suitable" when adding comprehensibility considerations. The amended SAM tool better identified content-related issues specific to SDSs that make it difficult for a reader to understand the material. Conclusions: In terms of readability, comprehensibility, and suitability, SDSs perform poorly in their primary role as a hazard communication tool, therefore, putting workers at risk. The amended SAM tool could be used when writing SDSs to ensure that the information is more easily understandable for all audiences.

Chinese buffer material for high-level radiawaste disposal --Basic features of GMZ-l

  • WEN Zhijian
    • 한국방사성폐기물학회:학술대회논문집
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    • 한국방사성폐기물학회 2005년도 Proceedings of The 6th korea-china joint workshop on nuclear waste management
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    • pp.236-244
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    • 2005
  • Radioactive wastes arising from a wide range of human activities are in many different physical and chemical forms, contaminated with varying radioactivity. Their common feature is the potential hazard associated with their radioactivity and the need to manage them in such a way as to protect the human environment. The geological disposal is regarded as the most reasonable and effective way to safely disposal high-level radioactive wastes in the world. The conceptual model of geological disposal in China is based on a multi-barrier system that combines an isolating geological environment with an engineered barrier system. The buffer is one of the main engineered barriers for HLW repository. The buffer material is expected to maintain its low water permeability, self-sealing property, radio nuclides adsorption and retardation property, thermal conductivity, chemical buffering property, overpack supporting property, stress buffering property over a long period of time. Benotite is selected as the main content of buffer material that can satisfy above. GMZ deposit is selected as the candidate supplier for Chinese buffer material of High Level Radioactive waste repository. This paper presents geological features of GMZ deposit and basic property of GMZ Na bentonite. GMZ bentonite deposit is a super large scale deposits with high content of Montmorillonite (about $75\%$) and GMZ-l, which is Na-bentonite produced from GMZ deposit is selected as reference material for Chinese buffer material study.

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