Urban rail transit(URT) has been playing an important role in urban sustainable development with its advantages of high speed,large capacity,high efficiency and low pollution.Estimating URT network scale is the key to...Urban rail transit(URT) has been playing an important role in urban sustainable development with its advantages of high speed,large capacity,high efficiency and low pollution.Estimating URT network scale is the key to ensure the scientificity and feasibility of its construction.The existing studies on rational scale of URT network have not dealt with the interaction of supply and demand.This paper describes the establishment of a system dynamics model of rational URT network scale determination,considering the interaction between URT construction and city social economic development as well as the dynamic equilibrium of capital supply and traffic demand,and the verification of the model validity by applying it to the case of Wuhan City's URT construction.展开更多
The skip-stop operation strategy （SOS） is rarely applied to Chinese urban rail transit networks because it is a simple scheme and a less universally popular transportation service. However, the SOS has performance a...The skip-stop operation strategy （SOS） is rarely applied to Chinese urban rail transit networks because it is a simple scheme and a less universally popular transportation service. However, the SOS has performance advantages, in that the total trip time can be reduced depending on the number of skipped stations, crowds of passengers can be rapidly evacuated at congested stations in peak periods, and the cost to transit companies is reduced. There is a contradiction between reducing the trip time under the SOS and increasing the passengers＇ waiting times under an all-stop scheme. Given this situation, the three objectives of our study were to minimize the waiting and trip times of all passengers and the travel times of trains. A comprehensive estimation model is presented for the SOS. The mechanism through which the trip time for all passengers is affected by the SOS is analyzed in detail. A 0-I integer programming formulation is established for the three objectives, and is solved using a tabu search algorithm. Finally, an example is presented to demonstrate that the estimation method for the SOS is capable of optimizing the timetable and operation schemes for a Chinese urban rail transit network.展开更多
城市轨道交通通信网络的设计与优化在提升系统性能和确保通信质量方面至关重要。分析系统需求,包括高速数据传输与实时监控、广泛的覆盖能力等关键要素。在此基础上,提出分层架构的网络设计,涵盖应用层、核心层、接入层以及列车层,以满...城市轨道交通通信网络的设计与优化在提升系统性能和确保通信质量方面至关重要。分析系统需求,包括高速数据传输与实时监控、广泛的覆盖能力等关键要素。在此基础上,提出分层架构的网络设计,涵盖应用层、核心层、接入层以及列车层,以满足不同通信需求。在无线通信技术优化方面,采用正交频分复用(Orthogonal Frequency Division Multiplexing,OFDM)、波束赋形技术和自适应调制与编码(Adaptive Modulation and Coding,AMC)等先进信号传输技术。同时,合理使用网络拓扑结构,如星型拓扑结构、分布式拓扑结构和混合型拓扑结构。此外,实施高效的信道编码、多址接入技术和动态频谱接入策略,以增强数据传输效率。为了优化无线覆盖范围,最大化信号覆盖和减少干扰,探讨天线配置与选择,包括定向天线、全向天线和组合天线的应用,强调合理的天线布局与信号优化策略。通过信号覆盖仿真软件的评估和现场测试,确保网络在实际部署中达到最佳性能。展开更多
基金Funded by Independent Innovation Grant of Huazhong University of Science & Technology (No. M2009013)
文摘Urban rail transit(URT) has been playing an important role in urban sustainable development with its advantages of high speed,large capacity,high efficiency and low pollution.Estimating URT network scale is the key to ensure the scientificity and feasibility of its construction.The existing studies on rational scale of URT network have not dealt with the interaction of supply and demand.This paper describes the establishment of a system dynamics model of rational URT network scale determination,considering the interaction between URT construction and city social economic development as well as the dynamic equilibrium of capital supply and traffic demand,and the verification of the model validity by applying it to the case of Wuhan City's URT construction.
基金financed by the National Basic Research Program of China, under project ID 2012CB725403
文摘The skip-stop operation strategy （SOS） is rarely applied to Chinese urban rail transit networks because it is a simple scheme and a less universally popular transportation service. However, the SOS has performance advantages, in that the total trip time can be reduced depending on the number of skipped stations, crowds of passengers can be rapidly evacuated at congested stations in peak periods, and the cost to transit companies is reduced. There is a contradiction between reducing the trip time under the SOS and increasing the passengers＇ waiting times under an all-stop scheme. Given this situation, the three objectives of our study were to minimize the waiting and trip times of all passengers and the travel times of trains. A comprehensive estimation model is presented for the SOS. The mechanism through which the trip time for all passengers is affected by the SOS is analyzed in detail. A 0-I integer programming formulation is established for the three objectives, and is solved using a tabu search algorithm. Finally, an example is presented to demonstrate that the estimation method for the SOS is capable of optimizing the timetable and operation schemes for a Chinese urban rail transit network.
文摘城市轨道交通通信网络的设计与优化在提升系统性能和确保通信质量方面至关重要。分析系统需求,包括高速数据传输与实时监控、广泛的覆盖能力等关键要素。在此基础上,提出分层架构的网络设计,涵盖应用层、核心层、接入层以及列车层,以满足不同通信需求。在无线通信技术优化方面,采用正交频分复用(Orthogonal Frequency Division Multiplexing,OFDM)、波束赋形技术和自适应调制与编码(Adaptive Modulation and Coding,AMC)等先进信号传输技术。同时,合理使用网络拓扑结构,如星型拓扑结构、分布式拓扑结构和混合型拓扑结构。此外,实施高效的信道编码、多址接入技术和动态频谱接入策略,以增强数据传输效率。为了优化无线覆盖范围,最大化信号覆盖和减少干扰,探讨天线配置与选择,包括定向天线、全向天线和组合天线的应用,强调合理的天线布局与信号优化策略。通过信号覆盖仿真软件的评估和现场测试,确保网络在实际部署中达到最佳性能。
