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排序方式: 共有512条查询结果,搜索用时 15 毫秒
201.
重庆轨道交通2号线是我国第一条跨座式单轨线路,2004年运营至今客流急剧增加,现状客流已达到远期设计客流,正线运营行车间隔已缩短至3 min,从而对车辆段的出段能力提出了更高的要求.车辆段出段能力的主控制因素是段内发车能力,对白居寺车辆段段内发车能力的研究不仅能提升该车辆段的出段能力,而且对提升2号线的运营效率和降低运... 相似文献
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203.
对基于同步压缩小波变换提取瞬时频率的方法进行改进,使之可完整、准确地提取振动信号的瞬时频率曲线,避免因时频聚集性较差以及交叉项的干扰带来的问题。采用该方法对高速综合检测列车轴箱加速度数据进行时频分析,提取钢轨短波不平顺的瞬时频率,根据其变化特性精确定位钢轨疑似波磨和打磨痕迹区段。结果表明:轴箱加速度波形均呈现周期性;分析区段的振动数据中包含150和75mm 2种波长呈现倍数关系的强振动数据,现场测试发现该处存在较强的钢轨波磨现象,波磨波长为150mm,同时现场还存在波长为75mm的钢轨周期性打磨痕迹;75mm的钢轨周期性打磨痕迹引起轮轨系统的非线性振动,振动频率达到1 125Hz,与扣件固有频率562Hz呈倍频关系,导致扣件产生强烈的共振,从而引发轮-轨接触共振,造成钢轨表面产生塑性变形,形成塑流性波磨,在列车的反复作用下,该处产生150mm波长的波磨。 相似文献
204.
《铁道标准设计通讯》2017,(5):45-49
城市外围组团快速发展,需要较大运量的接驳线快速衔接城市轨道交通资源,同时缓解组团内日益增长的交通压力。从接驳线的功能定位、规划条件、制式比选及衔接模式等方面进行分析,并以天津空港经济区为例进行较为系统的说明。中低运量的轨道交通系统和BRT(快速公交系统)均能满足接驳线的需求。接驳线的建设应在发挥现有公共交通能力的基础上进行充分论证,不宜过度超前;采用轨道交通系统时要处理好同既有轨道交通线网的关系。 相似文献
205.
实现城市轨道交通信号系统资源共享的基本形式有技术共享、操作界面和方式的共享、检修设备共享、人力资源共享、维修工艺共享、仿真培训设备资源共享等;信号系统互联互通的基本条件是:信号制式相同,系统结构和功能划分一致,地车信息传输系统兼容,列车定位技术兼容或统一,ATP安全控制方式统一设计和要求,列车驾驶模式和操作方式统一,信号与车辆接口相同,信号与PIS系统合理分配频道和接口;实现信号系统互联互通的基本手段有:采用同一厂商相同制式的信号系统,加装多套信号车载设备和地面设备.采用通用的信号车载设备,实现规范和标准的信号互联互通等.概括介绍国外轨道交通资源共享与互联互通的研究发展情况. 相似文献
206.
This paper explores how the selection of public transit modes can be optimized over a planning horizon. This conceptual analysis sacrifices geographic detail in order to better highlight the relations among important factors. First, a set of static models is proposed to identify which type of service, e.g., bus only, rail only, or bus and rail, is the most cost-effective in terms of the average trip cost for given demand. After analyzing essential factors in a long-term planning process, e.g., economies of scale in rail extension and future cost discounting, a dynamic model incorporating such considerations is formulated to optimize the decision over a planning horizon. While analytical solutions can be obtained for some decision variables, the final model is solved with a graphical method by exploring the tradeoffs between the initial and recurring costs. Major findings from this study include: (a) there exists a minimum economic length for a rail line, which can be determined numerically; (b) economies of scale favor large extensions and excess supplied capacity; (c) the rail-only service is largely dominated by the feeder-trunk service, even in the long run. 相似文献
207.
In this paper, we develop a new framework for strategic planning purposes to calculate railway infrastructure occupation and capacity consumption in networks, independent of a timetable. Furthermore, a model implementing the framework is presented. In this model different train sequences are generated and assessed to obtain timetable independence. A stochastic simulation of delays is used to obtain the capacity consumption. The model is tested on a case network where four different infrastructure scenarios are considered. Both infrastructure occupation and capacity consumption results are obtained efficiently with little input. The case illustrates the model’s ability to quantify the capacity gain from infrastructure scenario to infrastructure scenario which can be used to increase the number of trains or improve the robustness of the system. 相似文献
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209.
Despite the growing development of tools that can integrate land use and transport, the desired integration is still illusive in daily practice. To address this gap, the current study uses spatial metrics, a set of methods traditionally used for studying changes in the spatial structure of landscapes, which are translated into the domain of transport planning. It examines how spatial metrics can be integrated into “Land Use Transport” strategy-making, and how useful they are according to the practitioners’ perceptions. A Light Rail Transit corridor in Granada (Spain) provides the empirical focus of this research. Land use characteristics such as: land use mixing, land use diversity and green areas connectivity were successfully studied using spatial metrics, and they were used to map three “Land Use Transport” strategies: (i) proximity dynamics and non-motorised modes; (ii) modal shift from cars to Light Rail Transit system; (iii) shared spaces between motorised and non-motorised modes. Practitioners perceived that spatial metrics could improve the “Land Use Transport” strategy-making process in comparison with traditional methods used in practice. However, certain shortcomings related to the usability of spatial metrics are also highlighted and discussed. This study concludes with a reflection on research challenges for adapting spatial metrics to transport practice. 相似文献
210.
从线芯选择、铠装层选择、绝缘层选择方面对城市轨道交通33(35)kV环网电缆结构选型作了分析,综合考虑实际施工时可能产生的影响,得出了较适宜城市轨道交通的33(35)kV环网电缆的型号。 相似文献