地面爆燃式电打火装置在火炬上的应用

介绍了地面爆燃式电打火装置的结构及安装要点,实践表明该装置点火效率高、故障率低、便于检修,非常适合石油化工行业的火炬打火系统。     

井架背车液压系统故障诊断与处理

介绍了井架背车液压系统常见故障现场快速诊断方法,列举了常见故障处理实例及故障诊断效果。     

Traffic accident reconstruction and an approach for prediction of fault rates using artificial neural networks: A case study in Turkey

Objective: Currently, in Turkey, fault rates in traffic accidents are determined according to the initiative of accident experts (no speed analyses of vehicles just considering accident type) and there are no specific quantitative instructions on fault rates related to procession of accidents which just represents the type of collision (side impact, head to head, rear end, etc.) in No. 2918 Turkish Highway Traffic Act (THTA 1983). The aim of this study is to introduce a scientific and systematic approach for determination of fault rates in most frequent property damage–only (PDO) traffic accidents in Turkey.

Methods: In this study, data (police reports, skid marks, deformation, crush depth, etc.) collected from the most frequent and controversial accident types (4 sample vehicle–vehicle scenarios) that consist of PDO were inserted into a reconstruction software called vCrash. Sample real-world scenarios were simulated on the software to generate different vehicle deformations that also correspond to energy-equivalent speed data just before the crash. These values were used to train a multilayer feedforward artificial neural network (MFANN), function fitting neural network (FITNET, a specialized version of MFANN), and generalized regression neural network (GRNN) models within 10-fold cross-validation to predict fault rates without using software. The performance of the artificial neural network (ANN) prediction models was evaluated using mean square error (MSE) and multiple correlation coefficient (R).

Results: It was shown that the MFANN model performed better for predicting fault rates (i.e., lower MSE and higher R) than FITNET and GRNN models for accident scenarios 1, 2, and 3, whereas FITNET performed the best for scenario 4. The FITNET model showed the second best results for prediction for the first 3 scenarios. Because there is no training phase in GRNN, the GRNN model produced results much faster than MFANN and FITNET models. However, the GRNN model had the worst prediction results. The R values for prediction of fault rates were close to 1 for all folds and scenarios.

Conclusions: This study focuses on exhibiting new aspects and scientific approaches for determining fault rates of involvement in most frequent PDO accidents occurring in Turkey by discussing some deficiencies in THTA and without regard to initiative and/or experience of experts. This study yields judicious decisions to be made especially on forensic investigations and events involving insurance companies. Referring to this approach, injury/fatal and/or pedestrian-related accidents may be analyzed as future work by developing new scientific models.     

基于故障树分析法研究变电站检修触电事故防控

对变电站检修工作人员触电事故进行了故障树分析,通过定性分析,得出最小割集和结构重要度,并提出变电站检修触电事故的预防控制措施。     

Public participation in NGO-oriented communities for disaster prevention and mitigation (N-CDPM) in the Longmen Shan fault area during the Wenchuan and Lushan earthquake periods

ABSTRACT

The Longmen Shan fault area in southwest China is one of the world’s most active earthquake zones. The epicenters of the two most recent earthquakes, the 2008 Wenchuan earthquake (8.0?Ms) and the 2013 Lushan earthquake (7.0?Ms), both of which caused serious losses, were only 85?km apart. Community-based disaster risk reduction is the foundation of the disaster management system pyramid and is critical to the success of ‘sustainable hazard mitigation’. Based on multiple collaborative stakeholder perspectives, this paper examines public participation in an NGO-oriented Community for Disaster Prevention and Mitigation (N-CDPM) in the period between the two earthquakes as a multi-stage problem; N-CDPM establishment, normal operations, disaster testing, and continuous improvement. Multi-stage field research was conducted in the affected areas in the Longmen Shan fault area to examine the collaboration in each stage, after which the differences were compared across the four stages based on eight key indices; scales, core stakeholders, core network stability, mean number of lines, mean collaborative level, governments, and individual and public organization participation. The government participation, individual participation, and public organization participation are then discussed. This paper provides a novel research approach to CDPM in multiple earthquake regions and gives rich insights into the collaboration between the government and the public for N-CDPM.     

系统故障演化过程不连续现象的原因及消除方法研究*

为研究系统故障演化过程中,通过原因事件得到的结果事件发生可能性与直接试验得到的结果事件发生可能性不同的问题,定义系统故障演化过程的不连续现象,研究不连续现象出现的原因和消除方法。根据不连续现象的程度将原因分为3层,第1层是基本的原因事件、结果事件或传递的概率错误造成的不连续;第2层是因素对应错误造成的概率错误;第3层是演化结构不清造成的错误。针对这些错误提出消除方法,基本方法包括试验法、结构分析法和逻辑推理法;第2层次使用空间故障树和因素空间等方法;第3层使用三值逻辑等方法。研究结果表明:导致不连续的原因是演化过程的结构性问题,消除的方法应根据实际情况进行选择和变化。     

基于可公度法的航材故障预测

介绍了可公度性的概念和可公度信息预测理论。应用可公度信息预测理论,以故障时间窗口期为研究对象,对航材故障预测进行了初步探索,进而建立了一种较为实用的预测模型,并且给出了具体算例,验证所建模型的科学性和有效性。通过与指数平滑法预测模型对比可看到可公度预测模型精度更高且计算模型更为简单,为航材故障次数预测提供了一种解决方案。进而可以更好地应用在实践当中,提高航材管理水平,保障飞行任务的完成。     

基于BN的FTA在通用航空风险评价中的应用

针对事故树分析法(FTA)在风险评价中的局限性,采用以事故树为基础建立的贝叶斯网络(BN)风险模型,对通用航空中的两机空中相撞事故进行分析和推理,对事故模型进行改进和修正时,注重基事件的多态性和事件间的逻辑合理性。根据贝叶斯推理得出的数据,找到了事故的主要致因。结果表明,基于BN的FTA既能向前预测顶事件的发生概率,又能向后诊断基本事件的后验概率,可以更好地对通用航空风险进行评价。     

电气设备触电危险因素分析

我国现阶段生产、生活中触电事故增加,采用故障树的分析方法,对用电设备触电事故进行危险因素分析,得出保护接地在供配电系统中的重要作用。简要介绍保护接地,并指出目前我国用电设备保护接地中存在的问题及接地故障的防范措施。     

长江干线船舶碰撞原因的故障树分析一以武汉海事局辖区水域为例

以2007年武汉海事局辖区船舶碰撞资料为基础,利用故障树分析方法构建该水域船舶碰撞故障树,进行定性、定链分析,得到包括航行疏于戒备、车舵控制失误、疏于了望等14个主要危险因素及各因素的相关事故数。在故障树分析的基础上,构建布尔代数和最小割集,计算各危险旧素的概率重要度,以衡精各危险因素发生概率的变化给碰撞事故发生概率带来的影响;计算临界重要度,从敏感度和概率双重角度衡量每个危险因素的重要度。通过分析发现应急操作不当、违反其他规定、航行疏于戒备、违反分道通航、疲劳驾驶等人为因素是引起该水域船舶碰撞的重要原因。建议船公司重视船员应急培训,提高船员应急处置能力,海事管理机构加大相关法规宣传力度和监管力度。