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151.
Capturing the dynamics in passenger flow and system utilization over time and space is extremely important for railway operators. Previous studies usually estimated passenger flow using automatic fare collection data, and their applications are limited to a single stopping pattern and/or a single type of ticket. However, the conventional railway in Taiwan provides four types of ticket and five types of train service with a number of stopping patterns. This study develops a comprehensive framework and corresponding algorithms to map passenger flow and evaluate system utilization. A multinomial logit model is constructed and incorporated in the algorithms to estimate passenger train selection behavior. Results from the empirical studies demonstrate that the developed framework and algorithms can successfully match passengers with train services. With this tool, operators can efficiently examine passenger flow and service utilization, thereby quickly adjusting their service strategies accordingly to improve system performance. 相似文献
152.
为解决传统勘察手段及方法很难查明岩溶发育特征的难题,以昆明轨道交通4 号线岩溶专项勘察为案例工程,介绍在岩土工程初步勘察、详细勘察的基础上,采用以工程地质钻探及现场物探测试(孔间层析成像(CT)、高密度电法、地质雷达)为主,并结合工程地质测绘、原位测试、钻孔抽水试验和室内土工试验等综合勘察技术手段和方法,查明了线路沿线的岩溶分布、规模及形态等发育特征,并对其做出定量或定性评价,为岩溶专项治理施工图设计、优化设计方案及完善施工组织设计等提供了可靠的地质依据,对类似工程具有一定的指导及参考作用。 相似文献
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轨道固定系统是起重机平稳安全运行的基础,文章从轨道的受力分析出发,比较说明有缝轨道鱼尾板硬式固定系统和无缝轨道柔性固定系统的优缺点。 相似文献
157.
轨道交通牵引供电系统仿真中的算法研究 总被引:1,自引:0,他引:1
由于城市轨道交通直流供电系统建模后表现出非线性特性,对模型求解的仿真算法大都基于迭代技术。文章介绍了双重线性迭代和牛顿迭代两种算法,并从收敛效果和快速性两方面对它们进行了测试对比分析,同时通过改变电路结构模型和选用合适的迭代算法得到了理想的仿真效果。 相似文献
158.
长钢轨焊接是铺设无缝线路的一个极其特殊和重要的过程,原因在于其内部质量的好坏不能通过后续检验来判定,直接危及运输行车安全;其几何外形尺寸的平顺是保证无缝线路正常运用的关键。钢轨焊接质量不良,将使线路维修工作后患无穷,因此有效控制钢轨焊接质量成为目前急需探讨和解决的新课题。 相似文献
159.
A well-designed service plan efficiently utilizes its infrastructure and ensures an acceptable level of service stability with consideration of potential incidents that disturb or disrupt the rail transit services. To perform service evaluation, an integrated process combining capacity, resource usage, and system reliability is required to quantify service efficiency and stability in a consistent way. This study adopts capacity-based indices, “capacity utilization” and “expected recovery time”, as the attributes for service efficiency and stability, and develops a comprehensive evaluation framework with three corresponding modules to incorporate capacity, service plan, and system reliability and maintainability simultaneously. The capacity analysis module computes the rail transit capacities under normal and degraded operations. The reliability module classifies and fits the proper reliability and maintainability distributions to the historical interruption data. The service efficiency and stability module analyzes the results of the previous two modules and evaluates the service efficiency and stability of rail transit service plans. Empirical results show that the established evaluation framework can not only evaluate the service efficiency and stability but also identify critical sections and time slots. This tool can help rail transit operators rapidly assess their operational changes and investment strategies related to efficiency and stability so as to provide efficient and stable services to their customers. 相似文献
160.
Cost effective future derailment mitigation techniques for rail freight traffic management in Europe
Safe and reliable traffic management is vital for uninterrupted and successful operation of the European rail network, where mixed traffic (i.e. freight and passenger) services are run. Although rail freight derailment is infrequent, its consequences can be severe and may result in different forms of costs, including infrastructure; rolling stock; traffic disruptions; injuries and fatalities. The objective of this research paper is to conduct a cost benefit analysis (CBA) to identify cost effective mitigation techniques for efficient rail freight traffic management in Europe, by 2050. Reviewing previous derailments and studies, eight sets of derailment causes are analysed and, for each of them, sets of mitigation techniques are aimed at for their alleviation. The study finds that the highest cumulative costs of derailment are associated with ‘wheel failure’, while the lowest cumulative cost is identified for ‘excessive track width’. Regarding mitigation techniques, the lowest cumulative benefits are demonstrated for ‘track height’ interventions, whereas ‘wheel failure’ alleviation demonstrates the highest benefits, in value terms (all by 2050). In most cases, the benefit to cost ratio did not exceed 2.6; in two cases (‘track height’ and ‘rail failures’) the ratio remained below 1 – a negative outcome where cost is higher than benefit. The study suggests that the most cost-efficient interventions are those applied to ‘hot axle box and axle rupture’ and ‘spring and suspension failure’. 相似文献