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针对模糊Petri网在故障诊断中缺乏较强的自学习能力的缺点,将人工神经网络引入到模糊Petri网中,定义一种模糊神经Petri网,应用于天然气长输管道故障诊断,对过程中的故障诊断进行建模,通过分析说明该方法的可行性。 相似文献
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<正>自百度、谷歌、360搜索等搜索引擎对以"地铁事故"为关键词的搜索结果进行盘点之后发现,在历年地铁事故引发原因的文章中出现最多的字眼即为"信号故障"。经媒体"曝光"过的"地铁信号系统故障"屡见报端,引来不少普通民众质疑,为何"信号故障"成为地铁"大患"并屡治屡犯?对于节奏不断加快的现代城市生活来说,轨道交通在公众的日常生活中占据着举足轻重的地位,因而只要地铁运营发生延误,大家可能就会产生"信号系统又发生故障了"的错觉。 相似文献
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从地铁牵引供电系统的内容入手,阐述地铁的供电方式,分析当前影响地铁牵引供电系统可靠性和安全性的因素,并提出提高供电系统可靠性和安全性的有效策略. 相似文献
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Gleig Frazer 《现代隧道技术》2004,(Z2):85-91
当要全面考虑伦敦地铁的维护或将来的发展时,若对伦敦地铁历史(见附录)有个初步的了解将会是很有帮助的.这个系统的发展已经超过100年了,并且只是最近才改由一个独立的机构来管理.本文将部分地解释不同线间施工差异的复杂性.伦敦地下结构的大部分是地铁隧道,其中一些隧道自从在19世纪被建造以来还从来没有被完全评估过.当时,他们所使用的材料的物理性质和耐久性还不是完全地被人们所了解;如果这些隧道真是被"设计"的话,而且人们也只是按照经验来设计这些隧道的.当在1998年公私合营企业(PPP)刺激该程序最早开始实施的时候,隧道资产中的一些竖井和其它一些部分似乎已经被遗忘或丢失了.当前维护计划的一个主要部分就是确定需要维护和改善的大约178 km的地铁隧道资产现在所处的状况. 相似文献
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为了有效降低地铁运营中的安全风险,阐述地铁行车中调度指挥安全控制的重要性,以及地铁行车调度安全指挥过程中存在的安全隐患,并提出基于地铁行车的调度指挥安全控制策略,为提升地铁运营安全水平提供可行思路。 相似文献
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随着科技的发展进步,人们的生活水平正在不断提高,生活节奏也在不断加快,城市化建设进程也在日渐加速。地铁作为城市的主要交通工具之一,不仅可以带动城市发展,更能够方便人们出行,地铁检修也是地铁有效运行的重要保障,其中辅助供电系统是地铁检修工作的重点内容,而辅助逆变器作为辅助供电系统的重要组成部分,不仅直接关系到地铁车辆的运行安全,更影响着人们的生命财产安全。本文主要从绝缘栅双极晶体管(IGBT)元件故障及逆变器过流故障两方面分析地铁辅助逆变器发生故障的原因,提出其检测方式及整改措施。 相似文献
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当前城市的发展为地铁建设创造了一定的发展优势,由于盾构法具有地面作业少、自动化技术水平较高、对周边环境影响较小等优势,因此被广泛应用于地铁项目施工中.鉴于此,对盾构法施工技术进行详细的分析. 相似文献
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基于地下水动力学的地铁隧道裂隙水预测分析 总被引:2,自引:0,他引:2
针对城市中土岩组合的矿山法地铁隧道的实际情况,文章基于隧道潜水含水体的连续多孔介质模型建立了潜水含水体与裂隙含水体的组合介质分析模型;结合地下水动力学理论,推导了适用于该模型的裂隙水涌水量预测公式,并给出了公式中参数的具体取值方法,提出了该公式在地铁隧道注浆加固断面的涌水量预测中的应用方法。以青岛地铁隧道工程为依托,分别用解析法和数值分析法预测了隧道的涌水量,并与现场试验测量值进行了对比分析。分析结果表明,解析公式预测值误差较小,具有较高的工程应用价值。最后,分析了不同的洞室形状对隧道涌水的影响,得出了在地铁工程中断面形状对涌水量影响较小的结论。基于以上研究,文章推导的解析公式对土岩组合地层中地铁隧道涌水量的预测具有较高的适用性。 相似文献
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The Traffic Alert and Collision Avoidance System (TCAS) is a world-wide accepted last-resort means of reducing the probability and frequency of mid-air collisions between aircraft. Unfortunately, it is widely known that in congested airspace, the use of the TCAS may actually lead to induced collisions. Therefore, further research regarding TCAS logic is required. In this paper, an encounter model is formalised to identify all of the potential collision scenarios that can be induced by a resolution advisory that was generated previously by the TCAS without considering the downstream consequences in the surrounding traffic. The existing encounter models focus on checking and validating the potential collisions between trajectories of a specific scenario. In contrast, the innovative approach described in this paper concentrates on quantitative analysis of the different induced collision scenarios that could be reached for a given initial trajectory and a rough specification of the surrounding traffic. This approach provides valuable information at the operational level. Furthermore, the proposed encounter model can be used as a test-bed to evaluate future TCAS logic changes to mitigate potential induced collisions in hot spot volumes. In addition, the encounter model is described by means of the coloured Petri net (CPN) formalism. The resulting state space provides a deep understanding of the cause-and-effect relationship that each TCAS action proposed to avoid an actual collision with a potential new collision in the surrounding traffic. Quantitative simulation results are conducted to validate the proposed encounter model, and the resulting collision scenarios are summarised as valuable information for future Air Traffic Management (ATM) systems. 相似文献
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利用标准正态化转换多项式方法(SNTP)进行边坡可靠度分析,建立了精确的SNTP,并经过算例进行了验证;通过修正SNTP对高阶矩法进行了改进,利用边坡可靠度分析验证了其准确性和应用性。 相似文献
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This paper investigates the reliability of information on prevailing trip times on the links of a network as a basis for route choice decisions by individual drivers. It considers a type of information strategy in which no attempt is made by some central controller or coordinating entity to predict what the travel times on each link would be by the time it is reached by a driver that is presently at a given location. A specially modified model combining traffic simulation and path assignment capabilities is used to analyze the reliability of the real-time information supplied to the drivers. This is accomplished by comparing the supplied travel times (at the link and path levels) to the actual trip times experienced in the network after the information has been given. In addition, the quality of the decisions made by drivers on the basis of this information (under alternative path switching rules) is evaluated ex-post by comparing the actually experienced travel time (given the decision made) to the time that the driver would have experienced without the real-time information. Results of a series of simulation experiments under recurrent congestion conditions are discussed, illustrating the interactions between information reliability and user response. 相似文献
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More than 9 million passengers take Shanghai’s subway system every work day. The system’s air quality has caused widespread concern because of the potential harm to passengers’ health. We measured the particulate matter (PM) concentrations at three kinds of typical underground platform (side-type, island-type, and stacked-type platforms) and inside the trains in Shanghai’s metro during 7 days of measurements in April and July 2015. Our results demonstrated that the patterns of air quality variation and PM concentrations were similar at the side-type and island-type platforms. We also found that the PM concentrations were higher on the platforms than inside the train and that the PM concentrations in the subway system were positively correlated with those in the ambient air. Piston wind generated by vehicle motion pushes air from the tunnel to the platform, so platform PM concentrations increase when trains approach the platform. However, the piston wind effect varies greatly between locations on the platform. In general, the effect of the piston wind is weaker at the middle of the platform than at both ends. PM concentrations inside the train increase after the doors open, during which time dirty platform air floods into the compartments. PM1.0 and PM2.5 were significantly correlated both inside the train and on the platforms. PM1.0 accounted for 71.9% of PM2.5 inside the train, which is higher than the corresponding platform values. Based on these results, we propose some practical suggestions to minimize air pollution damage to passengers and staff from the subway system. 相似文献
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通过对广州地铁西草区间两台盾构机现场实测刀盘转速、刀盘扭矩数据,结合盾构配置的电机、液压泵、马达、减速箱的铭牌标定参数,计算分析得出制造商配置的减速箱并不能满足招投标时的产品承诺和现场实际需要。 相似文献
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钢丝绳电容监测系统是指专门用来监测索道钢丝绳对地绝缘电阻的装置。章通过对该系统工作原理的分析,阐述了该监测装置在索道安全运行中的地位和作用。 相似文献
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Donghyung Yook 《运输规划与技术》2015,38(8):935-953
In this paper, the crowding effect in a transit vehicle is modeled in a time-expanded network that considers the daily variation in passenger flows. The study models the daily variation of in-vehicle crowding in a real large-scale transit system. A transit assignment for this real network is modeled and implemented by constructing a crowding cost function that follows the valuation of crowding and by using the reliable shortest path finding method. The direct application of the crowding model to a real network for the Utah Transit Authority indicates that crowd modeling with multi-user classes could influence public transportation system planning and affect the revenues of transit agencies. Moreover, the addition of the disutility factor, crowding, does not always appear to cause an increase in disutility for transit users. 相似文献