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1.
通过解析EN 50129标准中质量、安全管理的要求,探讨企业在实施铁路信号电子产品产业化过程中的实施要点。  相似文献   
2.
A sensitivity analysis has been performed to assess the influence of the elastic properties of railway vehicle suspensions on the vehicle dynamic behaviour. To do this, 144 dynamic simulations were performed modifying, one at a time, the stiffness and damping coefficients, of the primary and secondary suspensions. Three values were assigned to each parameter, corresponding to the percentiles 10, 50 and 90 of a data set stored in a database of railway vehicles. After processing the results of these simulations, the analysed parameters were sorted by increasing influence. It was also found which of these parameters could be estimated with a lesser degree of accuracy in future simulations without appreciably affecting the simulation results. In general terms, it was concluded that the highest influences were found for the longitudinal stiffness and the lateral stiffness of the primary suspension, and the lowest influences for the vertical stiffness and the vertical damping of the primary suspension, with the parameters of the secondary suspension showing intermediate influences between them.  相似文献   
3.
The summer minimum extent of Arctic sea ice shrank drastically in these years, and the opportunity on Arctic international shipping emerged. The Northern Sea Route (NSR), formerly blocked by permanent ice, was completely ice-free in September in the past 3 years. Because this route is much shorter than conventional Asia–Europe shipping lane, many maritime countries have paid attention to exploit the enormous potential of the Arctic Ocean from economical consideration. This study measured the economical advantage of the seasonal NSR by calculating the shipping cost saved.  相似文献   
4.
机车车辆车体上安装的部件在工作过程中主要承受振动载荷,作为部件的载体机械结构的可靠性至关重要。对目前被广泛采用的对车体部件可靠性做出相关规定的标准IEC 61373和EN 12663进行分析,在累计损伤等效的前提下推导了随机振动与正弦振动的等效关系,为部件结构设计、可靠性试验提供了多种验证的手段,通过等效关系公式对两个标准中耐久性试验的振动量级进行比较,针对部件结构设计校核、耐久性试验中存在的问题提出了改进建议。  相似文献   
5.
高速铁路供电系统安全性评估研究   总被引:2,自引:1,他引:1  
研究目的:供电系统是高速铁路系统的重要组成部分,其安全可靠运行与铁路系统安全性密切相关。安全性评估是现代安全管理的重要一环。而我国在高铁供电系统安全性评估方面还只在定性阶段,缺乏定量评估指标和相应分析方法。本文在探讨系统安全性评估的方法、步骤的基础上将EN50126标准与铁路供电系统安全性评估相结合,分析提出了能反映系统各类风险发生概率和风险等级的定量安全性评估指标和安全性评估方法,为提高高铁供电系统的安全性管理水平提供参考。研究结论:基于事件树分析法(ETA)和改进的概率风险评估方法(LEC)相结合的安全性评估方法,对铁路供电段典型算例进行安全性定量评估分析,分别得到了各类供电设备的危险度指标和由其引发的系统安全风险等级,以及应采取的风险控制对策。说明本文提出的安全性量化指标和评估方法的有效性。  相似文献   
6.
为合理评价港珠澳大桥护栏的安全防护性能,对香港、澳门、内地三地护栏安全性评价规范进行对比分析,并结合相关规范修订完善的最新进展报告,确定港珠澳大桥护栏的评价指标。  相似文献   
7.
Recent studies to evaluate the quality of transit service are generating a good amount of renewed interest in an old idea, the passenger's perspective; this new interest stems from recognizing that transit service quality should be characterised, measured, and managed by parameters capturing both passenger and transit operator perspectives. However, although the selected parameters are user‐oriented in their input, the output may not be as user‐oriented as considered, and the number or the percentage of passengers is often neglected. As a result, the findings are often misleading because the perspectives of transit operators dominate. Therefore, academics and practitioners must rethink their strategies of quality analysis of public transportation by stressing more on the role of passengers. These challenges are addressed in this paper with a practical, simple, and holistic framework, for Transit Quality (TRANSQUAL). This framework provides for the involvement of all stakeholders in the characterisation, measurement, and management of the stages of quality monitoring, which is jointly analyzed at different planning levels. In the characterization stage, the framework supports the selection of parameters to be monitored. The measurement stage sets and measures four quality areas in terms of percentage of passengers who expect a predefined level of service, for whom the service is designed, who receive the planned service, and who perceive the service as delivered. The management stage computes the differences between these percentages, points out criticalities, and recommends corrective actions. These stages are investigated in‐depth, integrated, and discussed in a real‐life case study. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
8.
建立地铁车车厢及贯通道的三维物理模型,内部乘客站立密集.使用κ一ε标准湍流模型对地铁车车厢及贯通道处空气流场和温度场进行数值模拟,考虑了人体散热以及车体各组件对外部温度的传热作用,计算结果表明:贯通道内流场平均温度为22.5℃,气流组织速度范围约为0.1~0.3m/s.参照欧洲EN14750-1标准,贯通道内部空气流动速度及温度的热舒适性指标满足设计使用要求.  相似文献   
9.
从试验内容、试验载荷、试验工况组合和试验结果评定等方面对比了UIC、EN和JIS关于转向架构架强度试验的标准,并针对我国进行转向架构架强度试验给出了一些建议。  相似文献   
10.
Road restraint systems are roadside structures that include safety barriers, crash cushions, terminal of barriers, the transitions among different road restraint systems, motorcyclist protection devices, etc. These systems are used to protect vehicle occupants from dangerous roadside elements and are a key issue in roadside safety.  相似文献   
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