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751.
在系统分析目前应急能力评估研究存在问题的基础上,提出了石化企业应急能力评估方法,包括应急准备评估和重大事故情景应对能力评估。应急准备评估为定量评估,设置10个一级指标、26个二级指标、48个三级指标,每个指标依据权重赋值,按照得分情况分为5个等级。重大事故情景应对能力评估为定性评估,基于"情景-应对"的方式、从10个应急功能对现有应急能力进行分析,评估结果分为4个等级。提出的方法在某天然气生产企业进行了应用,结果表明方法科学、合理,可以帮助企业了解现有应急能力存在的不足。 相似文献
752.
分析了近年来因运行班组人员操作不当引发事故的原因,主要归结于日常安全管理工作和应急处置不当。提出在日常安全管理方面,操作人员须熟知岗位风险、防止“三违行为”和做好装置开停工期间的安全管理;在应急处置方面,需熟练掌握应急操作技能,培养反应快速、清晰的应急意识等措施,不断提高班组安全能力建设,以便更有效地控制安全风险,实现安全生产。 相似文献
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为提高建设地震安全社区减灾综合效益,解决我国地震频发造成的严重经济损失和人员伤亡,在发展尚未成熟的地震安全社区建设理念基础上探究其应急管理影响因素,从应急三阶段管理以及社会环境影响方面选取指标建立评价体系;引入AHP-熵权法和可拓物元数学理论,构建地震安全社区应急管理综合评价模型;应用该模型对大连地震安全社区进行实例验证,得出该社区应急管理等级以及应急全过程中不足之处,得到的评价结果与实际情况相符,表明多级可拓物元模型的定量计算结果准确可靠,对完善地震安全社区应急管理具有指导和实用价值。 相似文献
755.
成乾龙 《中国安全生产科学技术》2019,15(3):81-85
在煤层巷道垮落后需安全快速地开挖出1条应急救援巷道,为了了解开挖速率和法向压力对救援巷道稳定性的影响,通过将垮落的破碎煤视为均质散粒体的方式,采用相似模拟实验的手段,分析了剪切速率和法向压力对煤散体抗剪强度的影响。研究结果表明:煤散体的抗剪强度与其对应的法向应力存在线性关系,该关系近似符合莫尔库仑强度准则,但剪切强度增长率随法向压力增大而先增大后减小;在相同法向应力作用下,剪切速率对黏聚力的影响明显大于对内摩擦角的影响。 相似文献
756.
危险品事故泄漏模糊路网应急资源优化研究 总被引:1,自引:1,他引:0
当危险品大规模泄漏事故发生后,应急物资快速配送对于减轻危险品对人员伤害和挽救损失有重要意义。首先从损毁路网修复和救援物资2个方面建立双层模型,从有限物资分配修复损毁路网和救援上进行优化分配,并通过路径优化时间最短分配物资,使应急救援系统的损失最小化。利用宽容分层的方法对模型进行求解,求解最优的物资分配和运输路径方案。最后利用算例,对模型和算法进行检验,找出需要修复受损路网中关键路段。 相似文献
757.
Vertebrate animals can be injured or threatened with injury through human activities, thus warranting their “rescue.” Details of wildlife rescue, rehabilitation, release, and associated research (our 4 Rs) are often recorded in large databases, resulting in a wealth of available information. This information has huge research potential and can contribute to understanding of animal biology, anthropogenic impacts on wildlife, and species conservation. However, such databases have been little used, few studies have evaluated factors influencing success of rehabilitation and/or release, recommended actions to conserve threatened species have rarely arisen, and direct benefits for species conservation are yet to be demonstrated. We therefore recommend that additional research be based on data from rescue, rehabilitation, and release of animals that is broader in scope than previous research and would have community support. 相似文献
758.
John A. Kronenberger Jill C. Gerberich Sarah W. Fitzpatrick E. Dale Broder Lisa M. Angeloni W. Chris Funk 《Conservation biology》2018,32(4):838-848
Human land use is fragmenting habitats worldwide and inhibiting dispersal among previously connected populations of organisms, often leading to inbreeding depression and reduced evolutionary potential in the face of rapid environmental change. To combat this augmentation of isolated populations with immigrants is sometimes used to facilitate demographic and genetic rescue. Augmentation with immigrants that are genetically and adaptively similar to the target population effectively increases population fitness, but if immigrants are very genetically or adaptively divergent, augmentation can lead to outbreeding depression. Despite well‐cited guidelines for the best practice selection of immigrant sources, often only highly divergent populations remain, and experimental tests of these riskier augmentation scenarios are essentially nonexistent. We conducted a mesocosm experiment with Trinidadian guppies (Poecilia reticulata) to test the multigenerational demographic and genetic effects of augmenting 2 target populations with 3 types of divergent immigrants. We found no evidence of demographic rescue, but we did observe genetic rescue in one population. Divergent immigrant treatments tended to maintain greater genetic diversity, abundance, and hybrid fitness than controls that received immigrants from the source used to seed the mesocosms. In the second population, divergent immigrants had a slightly negative effect in one treatment, and the benefits of augmentation were less apparent overall, likely because this population started with higher genetic diversity and a lower reproductive rate that limited genetic admixture. Our results add to a growing consensus that gene flow can increase population fitness even when immigrants are more highly divergent and may help reduce uncertainty about the use of augmentation in conservation. 相似文献
759.
TIMOTHY J. SMYSER SCOTT A. JOHNSON L. KRISTEN PAGE CASSIE M. HUDSON OLIN E. RHODES JR. 《Conservation biology》2013,27(4):752-762
Translocations are an important tool for wildlife conservation, although progress in the field of reintroduction biology has been hindered by the ad hoc and opportunistic nature of many translocations. We used an experimental translocation to elucidate the role of raccoon roundworm (Baylisascaris procyonis) and inbreeding depression in the decline of the Allegheny woodrat (Neotoma magister), an endangered species. We translocated woodrats from genetically diverse populations in the core of the species range to 4 previously occupied sites (reintroductions) and 2 sites supporting genetically depauperate populations (reinforcements) in Indiana (U.S.A.). In 2 reintroduction sites and 1 reinforcement site, we distributed anthelmintic baits to passively deworm raccoons and reduce the risk of woodrat exposure to roundworms. The remaining sites served as controls. We used raccoon latrine surveys and fecal flotation to monitor temporal variability in roundworm prevalence and effect of treatment. We used live trapping and microsatellite genotyping to monitor the demographic and genetic response of translocated populations over the following 54 months. At the conclusion of the study, 4 of 6 translocations were successfully maintaining abundance through local recruitment. The distribution of anthelmintic baits reduced levels of roundworm contamination, but levels of contamination were also low in 2 of 3 control sites. Reintroductions failed at control sites, one of which was due to high roundworm exposure. The other failed control reintroduction was likely attributable to demographic stochasticity and limited reproductive potential following initial mortality within the first 4 months. In both control and treatment reinforcements, increases in both allelic richness and heterozygosity were accompanied by increases in abundance, which is suggestive of genetic rescue. Our results demonstrate that mitigation of roundworm exposure through the distribution of anthelmintic baits can facilitate woodrat recovery and that diversity within genetically depauperate populations can be restored through the introduction of a limited number of individuals. El Uso de Reubicaciones Experimentales de Neotoma magister para Descifrar Agentes Causales de Disminución 相似文献
760.