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211.
为提升建筑施工安全管理水平,探讨施工组织正式网络的结构特征对组织安全行为的影响关系。基于社会网络分析方法,引入安全沟通作为中介变量,建立施工组织正式网络结构特征、安全沟通和组织安全行为的假设模型。基于91个施工组织正式网络结构特征分析,使用多层回归分析方法检验假设模型。结果表明:网络密度、出度中心势和聚类系数均显著正向影响组织安全行为;中间中心势和平均路径长度均显著负向影响组织安全行为;入度中心势对组织安全行为影响不显著;安全沟通分别在出度中心势和中间中心势与组织安全行为的关系中起完全中介作用;安全沟通分别在密度、平均路径长度和聚类系数与组织安全行为的关系中起部分中介作用;安全沟通在入度中心势与组织安全行为的关系中未起到中介作用。 相似文献
212.
The inherent risks associated with accidental releases of hazardous materials during transport have drawn attention and concerns in the recent decades. The aim of this study is to propose a tool for evaluation and comparison of the transportation networks which can be used to assess the routing options between origins and destinations of the cargos for their suitability for transporting hazardous material cargos by tanker trucks and to identify routes which provide lower accidental release risks, lower public exposure risks, and offer economical benefits. Each route segment of transportation networks were evaluated using specific criteria which included health risk and cost of delay in case of an accidental release of materials, trucking cost and proximity to vulnerable areas. Since, the health impact of hazardous materials differ depending on the characteristics of the material being transported as well as release quantities and atmospheric conditions; this paper aimed in providing a tool that can be used to estimate the impact radius (for health risks) after accidental release of hazardous materials by taking into account different atmospheric conditions based on the meteorological data and solar elevation angle. The Gaussian air dispersion model paired with ArcGIS using Python programming were employed to estimate the health risk impact zones by considering the meteorological data, and accordingly to analyze road segments for cost impacts (delay and trucking costs), and the proximity to vulnerable areas. The route assessment tool was demonstrated with a case study. The results of this study can efficiently aid decision makers for transportation of hazardous materials. 相似文献
213.
为更加科学有效地辨识景区道路网络中的客流关键节点,以节点脆弱性为度量指标,提出1种基于FIM模型的关键节点脆弱性评价方法.以某大型公园为例,首先通过ArcGIS软件将该公园的道路网络信息转换成可编译的文本信息,经过Java枚举可行路径,然后利用嵌入FIM算法的Lingo进行优化,得出网络节点的重要度.最后综合节点容量、... 相似文献
214.
This study analyzes 46 brain and 48 spinal-cord impact experiments. The velocity of brain impact was 2.0-10.0 m/s and displacement, 0.75-5.0 mm (5.3-33% compression) using a controlled pneumatic impact. The velocity of spinal-cord impact was 1.5-6.0 m/s and displacement, 1.25-3.25 mm (25-65% compression). Brain injury varied from cortical contusion, diffuse axonal injury (DAI), to fatalities, and spinal-cord injury from temporary to complete loss of somatosensory-evoked potentials. Logist functions were determined for each injury severity and various biomechanical parameters, VC, C, V, and combinations. Brain and spinal-cord injury is most strongly correlated to VC, the viscous response. The goodness-of-fit was x2 = 22.1, R-0.84 and p< 0.0000 for fatal brain injury, x2 = 27.5, R = 0.96 and p< 0.0000 for cortical contusion, and x2 = 17.7, R = 0.49 and p < 0.0001 for partial recovery of spinal-cord conduction. Neural tissue is viscoelastic, with a rate-dependent tolerance related to energy absorption. VC is a measure of energy absorption by impact deformation and is predictive of neural contusion, DAI, long-duration coma, spinal-cord dysfunction, and death. Tolerances for various severities of neural injury are presented. At the tissue level, VC is the product of strain and strain-rate, ε dε/dt. The research shows that strain is not a sufficient parameter of neural injury risk, and that the product of strain and strain-rate is a key biomechanical parameter for brain and spinal-cord injury. 相似文献
215.
基于神经网络的重大危险源动态分级研究 总被引：8，自引：2，他引：8
利用自组织神经网络对重大危险源进行动态分级研究，介绍了神经网络的模式聚类即分级法的自组织学习过程和算法，克服了以往危险源分级方法的某些局限性。在计算机上进行的模拟计算表明：基于自组织神经网络的重大危险源动态分级方法是合理可行的 相似文献
216.
Loss of the underground gas storage process can have significant effects, and risk analysis is critical for maintaining the integrity of the underground gas storage process and reducing potential accidents. This paper focuses on the dynamic risk assessment method for the underground gas storage process. First, the underground gas storage process data is combined to create a database, and the fault tree of the underground gas storage facility is built by identifying the risk factors of the underground gas storage facility and mapping them into a Bayesian network. To eliminate the subjectivity in the process of determining the failure probability level of basic events, fuzzy numbers are introduced to determine the prior probability of the Bayesian network. Then, causal and diagnostic reasoning is performed on the Bayesian network to determine the failure level of the underground gas storage facilities. Based on the rate of change of prior and posterior probabilities, sensitivity and impact analysis are combined to determine the significant risk factors and possible failure paths. In addition, the time factor is introduced to build a dynamic Bayesian network to perform dynamic assessment and analysis of underground gas storage facilities. Finally, the dynamic risk assessment method is applied to underground gas storage facilities in depleted oil and gas reservoirs. A dynamic risk evaluation model for underground gas storage facilities is built to simulate and validate the dynamic risk evaluation method based on the Bayesian network. The results show that the proposed method has practical value for improving underground gas storage process safety. 相似文献
217.
污水处理厂出水总氮(TN)浓度是评价水处理效果的关键指标之一。建立BP神经网络模型对污水处理厂脱氮工艺进行模拟,引入自回归整合移动平均模型(ARIMA模型)对污水处理厂未来短期出水TN浓度进行预测。结果表明:BP神经网络模型在训练集和测试集模拟结果的平均相对误差分别为15.9%和16.5%,模型预测结果的平稳性较差;ARIMA模型对未来7 d出水TN浓度的时序预测平均误差为4.41%,预测精度较高;2个模型相结合有助于实现污水处理厂快捷和高效的在线检测。 相似文献
218.
介绍了锡矿山矿务局北矿童家院区北风井通风系统建立的过程,对北风井通风系统投产运行的实际效果进行了评价. 相似文献
219.
温晓杰 《中国安全科学学报》2019,29(Z2):187-194
为提升对铁路行车事故的应急救援效率、减小铁路行车事故损失及影响,通过分析铁路行车事故救援工作现状,找出救援管理工作存在的问题和弊端,研究探索解决的途径和办法,形成铁路行车事故的监测、预测、预警和快速反应、应急救援的机制,建立从铁总到集团公司、运输站段,从铁路部门到地方专业部门,从铁路系统救援力量到全社会应急救援力量,“横向到边,纵向到底”的立体化、多角度铁路行车事故救援快速反应网络,实现铁路行车事故救援快速化、高效化,追求铁路行车事故损失和影响最小化,促进铁路行车事故应急救援管理工作纳入经常化、制度化、法制化的轨道。 相似文献
220.
在实测数据的基础上,以邻苯二甲酸酯(PAEs)的各类影响因素为自变量,PAEs浓度为因变量,采用Back-propagation(BP)神经网络建立儿童卧室内PAEs浓度预测模型.结果表明,该模型的预测效果较理想,其中,STD比值均＞0.5,NMB均接近0,EMR均＜19％.以室内环境与儿童健康(CCHH)课题组天津地... 相似文献