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421.
浙江省台风灾害及应急机制建设 总被引:14,自引:6,他引:14
针对浙江省特殊的地理位置和气候条件,研究分析了台风灾害的特点以及应急机制建设的情况。在此基础上,提出了提高预防台风灾害能力的建议。 相似文献
422.
重大事故的应急救援预案编制技术 总被引:45,自引:12,他引:33
邢娟娟 《中国安全科学学报》2004,14(1):57-59
重大应急预案编制是安全生产的一项重要基础工作 ,对于提高应急救援能力 ,控制事故与灾害的恶化 ,保障人民安全具有重大意义。笔者从应急预案编制的技术层面上 ,论述了应急预案的基本框架和应急预案体系 ;认为该体系可以由 6个一级和 2 0个二级的核心要素构成。其中 ,应急策划是制定应急预案的技术基础 ,包括风险评价、资源分析和法律法规要求 3个二级要素 ;应急准备包括机构与职责、应急设备设施与物质、应急人员培训、预案演练、公众教育和互助协议 6个二级要素 ;应急响应是应急预案中核心的内容 ,包括现场指挥与控制等 1 1个二级要素。所提出的应急救援预案文件体系 ,建议一般按照四级文件形式的设想 ,应急预案的目标是提高整体应急能力 ;建议把应急预案的具体编制过程划分为 6个基本的步骤 ,对于预案编制与实施应实现持续改进的机制 相似文献
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Vincent H. Y. Tam Brian Corr 《Journal of Loss Prevention in the Process Industries》2000,13(6):588-447
The design of topsides against explosions requires the definition of a design over-pressure, however, these values are often treated as deterministic and there is a wide variation within the industry in the treatment and interpretation of the loads.
This paper advocates the adoption of a number of limit state for explosion loading. Events of different magnitudes are differentiated on the basis of frequency and linked to appropriate degree of reliability thus avoiding disproportionate effects from minor events.
The two principal limit states considered are a limit state for all the safety critical systems for relatively high frequency events and a survival condition for low probability events. Parallels are drawn from other branches of engineering where extreme loads have to be designed for. 相似文献
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427.
The idea that natural selection can be meaningfully applied at the group level may be more important than previously thought. This perspective, a modern version of group selection, is called multilevel selection. Multilevel selection theory could incorporate previous explanations for the evolution of cooperation including kin selection. There is general agreement that natural selection favors noncooperators over cooperators in the case of an unstructured population. Therefore, the evolution of cooperation by multilevel selection often requires positive assortment between cooperators and noncooperators. The question is how this positive assortment can arise in the ecological meaning. We constructed an individual-based model of multilevel selection and introduced migration and evolution. The results showed that positive assortment was generated especially when a migration strategy was adopted in which individuals respond specifically to bad environmental conditions. It was also shown that the founder effect in the evolutionary process could further facilitate positive assortment by working with migration. We analyzed assortment by using relatedness defined in group-structured populations. The fact that cooperation was achieved by such migration and by the founder effect highlights the importance of sensitiveness to the ecological environment and of fluctuations in group size, respectively. 相似文献
428.
摘要:为研制适用于煤矿瓦斯抽采钻孔、满足施工强度要求的小尺寸随钻超声成像仪器,对随钻超声成像仪器的关键受力部位——超声探头安装孔进行优化设计,分析煤矿瓦斯抽采钻孔的一般规格,建立超声探头安装孔的三维模型,确定关键参数类型及其取值范围,采用极差分析法找到对受力部件强度影响较大的参数,基于响应面法开展有限元数值模拟,运用Box-Behnken设计方法得到超声探头安装孔关键参数与仪器受力部件性能指标的关系,优化受力部件关键参数的数值。结果表明:优化前最大的等效应力为138.6 MPa,优化后受力部件最大等效应力较优化前降低9.05%。结论验证了设计方法的有效性,为煤矿抽采钻孔随钻测井仪器的研制提供思路。 相似文献
429.
Accidents involving contractors continue to occur with regular frequency. By using the standard set within the PSM 29 CFR 1910.119(h) regulations, it has been identified that certain aspects of the way contractors do work are not up to the stipulated regulatory requirements especially regarding matters like not providing mandatory personal protective equipment (PPE) to the workers, not discussing hazards related to handling procedures with the workforce and improper control of non-routine activities during changes in shifts. The PSM 29 CFR 1910.119(h) regulations promulgated in 1992 provides standards that covered processes to obtain and evaluate data regarding contractors' health and safety programs as well as the contractors' performance evaluation. Many of the accidents involving contractors are direct result of poor training of contractors and/or poor control of the contracted work. Even though most organizations have their own contractor management systems, there are issues in meeting the requirements of PSM. The PSM standard only state “what to do” not “how to do it”. This is known as self-regulatory policy which depends on the industries understanding to interpret the standard that also contribute to this problem. This paper presents a structured and easy technique to plan and implement a practical and comprehensive contractors' management system in process industries that will comply with OSHA CFR 1910.119. A model has been developed based on this technique and its application has been tested in a pilot plant for compliance to PSM regulation. The model is beneficial to the process industries as any deficiencies in the PSM contractors' management program will be highlighted by the model which will then easily correct the identified deficiency so as to minimize and prevent catastrophic accidents. 相似文献
430.
Lotaustralin from the root of Rhodiola rosea L was extracted using supercritical carbon dioxide with methanol as modifier. Response surface methodology using Box–Behnken experimental design was utilized to explore parameters for supercritical carbon dioxide extraction. The effects of various values of temperatures (50–70 °C), pressures (200--400 bar), and percentages of methanol modifier (80%–100%) on the extraction yields of lotaustralin were evaluated. Extract identification was performed using high-performance liquid chromatography. The experimental data obtained were fitted to second-order polynomial equations and assessed using analysis of variance. The highest yields predicted from the experiments were 2.05 g kg?1 lotaustralin at the optimal values, i.e. temperature 65 °C, pressure 316 bar, 88% methanol modifier at a flow rate of 0.4 mL min?1, and dynamic extraction time 90 min. 相似文献