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971.
为了合理地确定边坡的最不利滑裂面、探讨坡顶开裂原因及出现滑坡险情时的应急措施,将变分方法用于边坡稳定性分析。通过建立一个与边坡稳定相关的泛函,根据边界条件选取适当的基函数,获得了边坡最不利滑裂面。基于所得最不利滑裂面,得到垂直边坡和普通边坡最不利滑裂面的分布随土体内摩擦角和内聚力的变化趋势,为垂直边坡和普通边坡采取正确的应急措施、提高边坡的稳定性提供了理论依据;根据泛函T沿最不利滑裂面的变化将边坡划分为主动滑动区和被动滑动区。比较分析得出:变分方法和Bishop条分法所获得的安全系数比较接近,且变分方法获得的安全系数略小。 相似文献
972.
973.
分析了应对重大灾害的应急物资需求的特点和我国现有应急物资储备体系的现状和不足,基于轴辐网络优势,构建了轴辐式应急物资储备网络体系,分析了应急轴辐网络储备体系运行的四个阶段,同时提出了建立轴辐式应急物资储备网络相关具体措施建议,实现中央和地方应急储备库物资、各职能部门储备物资、军队物资、各社会团体储备物资、国内外捐助物资以及企业物资生产能力储备等专业应急物资储备和社会应急物资储备的有效整合,以有助于在较短时间内积聚大量应急物资,扩大应急物资的服务辐射范围,提高应急物资调度效率,以有效应对各类重大灾害。 相似文献
974.
975.
Lars Hendrik Simon Volker Wilkens Thomas Fedtke Michael Beyer 《Journal of Loss Prevention in the Process Industries》2013,26(6):1583-1589
This paper shows the results of our investigations on the ignition source ultrasound in dust-air atmospheres. Ultrasound is, on the one hand, considered to be an ignition source according to international safety standards (EN 1127–1 (2011)). On the other hand, though, ultrasound is used for various applications in gases and air, such as level and flow measurement, or in the process industry, but no explosion accidents have yet been reported. Our research now shows that it is indeed possible to ignite dust-air mixtures in ultrasound fields under certain conditions. We conducted our experiments in an ultrasound standing wave field and used maize starch, calcium stearate and sulfur dust. For ignitions, an absorbing target was needed to convert the acoustic energy into heat. From theoretical estimations and experiments critical conditions that provoke ultrasonically triggered explosions are identified. 相似文献
976.
为了解决震后应急物资调度中,因不考虑各应急需求点灾情差异和需求差异带来的决策结果不够合理的问题,采用改进的专家打分法将收集到的灾情信息量化为灾情因子,在此基础上建立应急成本和应急延误时间的多目标模型。采用逐步法求解,为每一个应急需求点确定提供应急物资的供应点及供应量。将此方法运用到云南发生的某地震灾后救援中,计算得出与3个应急需求点对应的应急供应点及其供应量。 相似文献
977.
Monique Lortie Geneviève Baril-Gingras 《International journal of occupational safety and ergonomics》2013,19(1):3-18
The handling of 2,306 boxes being loaded or unloaded from vans onto or from 4-wheeled trolleys by 31 handlers in a warehouse were characterized. Handling was videotaped and characterized through an analysis grid completed by three trained observers. The following execution parameters were observed: nature of the exertion applied by the upper limbs, plane and direction of the exertion, resulting displacement of the box, grip, use of the lower limbs and the back. Results show that execution parameters used by handlers vary considerably from those usually recommended or studied. For example, symmetric grips were rarely used (4%). The grip was modified during the handling of half the boxes. Significant knee flexion was rarely observed (3% of exertions). Each box was moved by applying an average of . 3.5 different exertions. Exertions were mostly applied in a plane parallel to the shoulders; they were rarely executed in a strict sagittal plane (11%). The implication of these observations are discussed. 相似文献
978.
Ann-Sofie Lindberg Christer Malm Juha Oksa Désirée Gavhed 《International journal of occupational safety and ergonomics》2013,19(2):309-321
Objectives. The present study sought to identify firefighters’ rated physical demands for the most frequently occurring work tasks and to determine if the ratings differed between full-time and part-time firefighters to help create a basis for the development of physical employment tests for firefighters. Methods. An extensive questionnaire was completed by 125 and 68 firefighters in 2000 and 2010, respectively. The data were analysed with the Mann-Whitney U test and binominal test and ranked on the basis of the responses in each category. Results. Significant differences were seen between the full- and part-time firefighters. The work tasks rated as the most physically strenuous in terms of aerobic fitness, muscle strength, work posture and body control by most respondents were smoke diving upstairs (carrying a hose), victim rescue in different ways, carrying a stretcher over terrain and pulling a hose. Conclusions. Physically strenuous work tasks should be included in the end-point performance variables used to select physical performance tests for firefighters. The part-time firefighters with no experience in several of the work tasks suggests that work-related exercises are important if both groups of firefighters are expected to do similar work. 相似文献
979.
网站是目前政府开展应急管理工作最具时效性和覆盖面最广的平台,各地纷纷在政府网站上设置应急管理专栏或开设专门的政府应急管理网站,逐渐把政府网站发展成为进行应急管理工作,提供应急服务的常态工具.构建了应急管理栏目(网站)评价指标体系,从10个方面对全国32个省市区的应急管理栏目(网站)进行综合比较,在此基础上分析省级政府应急管理网站功能建设现状、已取得的成效和建设中存在的主要问题,借鉴国内外应急管理网站的建设经验提出相应的改进建议. 相似文献
980.
中国石油数字化应急预案系统研究 总被引:1,自引:0,他引:1
中国石油高度重视应急预案体系建设工作,集团公司和所属企业均在风险分析的基础上,建立了“横向到边、纵向到底”的应急预案体系,为有效应对各类突发事件提供了重要的支持.旨在对文本应急预案的数字化应用技术进行研究,以进一步提高应急预案的可操作性.首先,探讨了数字化应急预案的概念,分析了国内外数字化应急预案系统技术的研究现状.其次,基于中国石油数字化应急预案系统的需求分析,从业务流程设计、系统部署设计和系统功能设计等三个方面对其进行了研究和分析.最后,立足于中国石油应急信息系统建设实际,提出了中国石油建设数字化预案系统建设的实施步骤. 相似文献