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991.
992.
香港特区建筑安全管理的探讨与借鉴 总被引:2,自引:2,他引:2
近年来 ,香港特区的建筑业安全状况有了长足进步 ,由于香港的发展既长期受到西方国家先进技术和知识的影响 ,同时又具有中国的传统文化背景 ,因此 ,研究其成功的经验对内地的建筑安全工作有着十分重要的借鉴意义。笔者主要从香港政府部门 (劳工处和环境运输工务局 )对建筑安全的管理和非政府机构 (职业安全健康局、绿十字会等 )对建筑安全的作用两方面进行探讨 ,总结香港特区在建筑安全方面的成功做法 ,最后对内地的建筑安全工作提出了一些建议。 相似文献
993.
军机易损性评估体系安全度值的研究 总被引:1,自引:1,他引:1
军机易损性评估至为关键的因素之一是可靠的确定评估指标的安全度值。基于模糊统计基础上的集值统计 ,能有效地确定具有随机、模糊性质的军机易损性评估指标的安全度值 ;在确定过程中 ,可以给出易损性评估指标安全度值的可靠性程度和各评估专家的偏离度。实例表明 ,该法弥补了目前军机易损性评估中由经典统计法确定安全度值的不足 ,提高了军机易损性评估的准确度和可靠度。 相似文献
994.
Multi-indicator assessment of water environment in government
environmental auditing 总被引:1,自引:0,他引:1
This study focused on a multi-indicator assessment methodology for governmental environmental auditing of water protection programs. The environmental status of Wuli Lake in China was assessed using the global indicators (driver-status-response) developed by the Commission on Sustainable Development, and four additional indicators proposed by the author: water quality, pollution load, aquatic ecosystem status, and lake sediment deposition. Various hydrological, chemical, biological and environmental parameters were used to estimate the values of the indicators for assessment of environmental status of the lake based on time series data sets for twenty years. The indicators proposed can be customized to meeting the needs for particular assessment of water protection programs. This method can be used to evaluate the performance of national environmental protection programs and provide technical support for environmental auditors. 相似文献
995.
Introduction: This study addressed a gap in the literature – the potential of using autonomous vehicles (AV) to enhance children’s mobility. Prior studies documented the perceived benefits and concerns about this prospect, but did not examine the features in AV and support mechanisms that are desired by potential users. Method: An on-line survey was used to collect public opinions within the United States. In the survey, willingness to use AVs for this use case was asked twice to assess if participants changed their mind after being asked about concerns related to this prospect and importance of car features. A combination of statistical and machine-learning methods were used to profile individuals with high versus low post-willingness and to identify variables that differentiated the two groups. Results: Results indicated that respondents who were lower on their post-willingness to use AVs to transport children were more concerned about how AVs would protect children, how someone could harm the children inside, and whether there would be someone at the destination. In addition, they were less in favor of technology, older in age, and rated car features such as having a designated adult waiting at destination, a camera, and a microphone as relatively required (as opposed to optional). These results highlight potential users’ needs and requirements as they think about AVs in the context of parent–children mobility practices. Practical Applications: Relevant stakeholders should develop deployment and implementation plans while taking into account ridership contexts and vulnerable road users who can benefit from enhanced mobility. 相似文献
996.
通过对现代石化流程状态转移模式的分析, 建立了系统安全度分析模型,提出了改善系统安全状态的策略,并列举了用于催化裂化装置的结果 相似文献
997.
The gas pipeline network is an essential infrastructure for a smart city. It provides a much-needed energy source; however, it poses a significant risk to the community. Effective risk management assists in maintaining the operational safety of the network. The risk management of the network requires reliable dynamic failure probability analysis. This paper proposes a methodology of condition monitoring and dynamic failure probability analysis of urban gas pipeline network. The methodology begins with identifying key design and operational factors responsible for pipeline failure. Subsequently, a causation-based failure model is developed as the Bowtie model. The Bowtie model is transformed into a Bayesian network, which is analyzed using operational data. The key contributory factors of accident causation are monitored. The monitored data is used to analyze the updated failure probability of the network. The gas pipeline network's dynamic failure probability is combined with the potential consequences to assess the risk. The application of the approach is demonstrated in a section of the urban gas pipeline. 相似文献
998.
O.H. Manscher N.Z. Heidam J. Vikelse P. Nielsen P. Blinksbjerg H. Madsen L. Pallesen T.O. Tiernan 《Chemosphere》1990,20(10-12)
During the last two years an extensive series of dioxin measurements has been conducted on Danish municipal and hospital solid waste incinerators. The study was directed toward finding the total annual dioxin emissions from MSWI in Denmark, now estimated to be 3 kg. of dioxines and furanes. This sum is equivalent to 50 g. of 2,3,7,8-TCDD according to the Nordic Equivalents. Measurements were carried out according to a statistical design following a plan of pre-randomized sampling. This procedure allowed causal interpretation of the correlations found between the dioxin emissions and certain operating parameters. The statistical model obtained describes the emissions by variations between incinerators, by variation in time, and by changes in the load, the excess air and the HCl concentration in the flue gas. 相似文献
999.
1000.
采用东方香蒲(Typha orientalis Presl)和铜绿微囊藻(Microcystis aeruginosa)共培养的试验方法研究了东方香蒲对铜绿微囊藻多糖及亚显微结构的影响。结果表明:在质量浓度为20 g/L和40 g/L的东方香蒲化感胁迫下,铜绿微囊藻总糖(TSP)、胞内多糖(IPS)及固着性胞外多糖(bEPS)含量呈现先增加后逐渐降低的趋势,溶解性胞外多糖(sEPS)含量在培养过程中呈现逐渐增加的趋势,表明东方香蒲化感胁迫在前期促进了铜绿微囊藻的多糖合成和分泌,但在培养后期抑制多糖合成,并进一步促进多糖分泌和溶解;在培养后期,藻细胞叶绿素荧光参数包括YⅡ(光系统Ⅱ有效量子产量)、ETR_(max)(线性最大电子传递速率)显著降低,表明东方香蒲对铜绿微囊藻的光合系统产生了明显的化感抑制,光合活性及光合效率明显下降;藻细胞亚显微结构显示,在培养后期,藻细胞类囊体片层分解断裂,表明经过持续地化感胁迫,东方香蒲诱导铜绿微囊藻产生氧化胁迫,藻的光合系统受到严重破坏。东方香蒲使用量越高,藻细胞结构损伤越严重。 相似文献