Optimal Allocation of Public Transport Hub Based on Load Loss Value and the Economy of Distribution Network

The rapid development of electric buses has brought a surge in the number of bus hubs and their charging and discharging capacities.Therefore,the location and construction scale of bus hubs will greatly affect the operation costs and benefits of an urban distribution network in the future.Through the scientific and reasonable planning of public transport hubs on the premise of meeting the needs of basic public transport services,it can reduce the negative impact of electric bus charging loads upon the power grids.Furthermore,it can use its flexible operation characteristics to provide flexible support for the distribution network.In this paper,taking the impact of public transport hub on the reliability of distribution network as the starting point,a three-level programming optimization model based on the value and economy of distribution network load loss is proposed.Through the upper model,several planning schemes can be generated,which provides boundary conditions for the expansion of middle-level optimization.The normal operation dispatching scheme of public transport hub obtained from the middle-level optimization results provides boundary conditions for the development of lower level optimization.Through the lower level optimization,the expected load loss of the whole distribution system including bus hub under the planning scheme given by the upper level can be obtained.The effectiveness of the model is verified by an IEEE-33 bus example.

30 years of the transformation of non-urban public transport in Poland's peripheral areas – what went wrong?

Transport-based social exclusion is currently a serious social problem in Poland,and one which is apparently most severe at the level of the county(Polish powiat)in the south-eastof the country,including the Beskid Niski and Bieszczady Mountains.A deeper illustration of this problem requires both observation of changes in the suburban public-transport network and the identification of areas in which this has deteriorated significantly in quantity and quality.The chosen starting point for the research was therefore 1990,as a year in which–on the one hand–the Polish economy was already shifted to the new free-market principles;while–on the other–state PKS(Przedsiębiorstwo Komunikacji Samochodowej)non-urban bus transport enterprises still dominated public transport.The endpoint of the study is then the beginning of 2019(the author's research year).The article introduced here seeks to identify and present cartographically the changes affecting the public-transport network in the study area over the last 30 years,as well as to point to possible consequences of these processes.The background of the described changes is also discussed,as are the observed consequences of what is taking place.

Open Queueing Network Model of Shanghai Public Transportation Problem

In this paper, the open queueing network model is proposed for solving the problem of public transportation in cities. The vertices of the networks(i.e., the bus stops) are determined by means of the fuzzy clustering method. The arcs (i.e., the paths of the public transportation) can be set up by using the shortest path model in the time sense or the 0 1 integer programming method.Applying the statistics method, we can calculate the parameters(such as the passenger flow's distribution, passenger flow's transition probability, mean waiting time for the bus etc. ) of the public transportation network. In this paper, we suggest to divide the network into two or three stages to implement the public transportation system in the form of ``frog jumping' fast transfer and ``permeation' fast dispersion.Combining the computer simulation and the evaluation of the achievement and effect of public transportation system, we modify the model so as to solve the public transportation problem better.

Optimization Processes of Tangible and Intangible Networks through the Laplace Problems for Regular Lattices with Multiple Obstacles along the Way

A systematic approach is proposed to the theme of safety,reliability and global quality of complex networks(material and immaterial)by means of special mathematical tools that allow an adequate geometric characterization and study of the operation,even in the presence of multiple obstacles along the path.To that end,applying the theory of graphs to the problem under study and using a special mathematical model based on stochastic geometry,in this article we consider some regular lattices in which it is possible to schematize the elements of the network,with the fundamental cell with six,eight or 2(n+2)obstacles,calculating the probability of Laplace.In this way it is possible to measure the“degree of impedance”exerted by the anomalies along the network by the obstacles examined.The method can be extended to other regular and/or irregular geometric figures,whose union together constitutes the examined network,allowing to optimize the functioning of the complex system considered.

Possible Sustainability of Intermodal Transportation in Africa

The lack of adequate and modern transport infrastructures makes the cost of transport in Africa higher than the rest of the world. Most of the transport infrastructures that exist were constructed during the colonial era which makes inter-regional connectivity difficult. The African Union in collaboration with other organization has committed to bridge the transport gap in Africa but still, face some challenges. This paper discusses the main issues that contribute for the weak nature of transportation in Sub-Saharan Africa with regards to the main transport modes and seeks to establish the possibility of sustainable intermodal transport through the integration of the different transport modes. Some policy reforms and other bilateral agreements such as deregulating the transport markets in West and Central Africa have been suggested to facilitate the development of an effective and efficient transport network in the Sub-Saharan African region.

Potential Benefits of Increased Public Transit Ridership in Medium Sized Cities: A Case Study

At the beginning of the twentieth century, the United States was leading in the public transit sector, but following World War II, private automobiles became more affordable and gained popularity. Transportation infrastructure investments that increased road capacity further facilitated the increase in automobile use at the expense of reduced public transit ridership. With the increase of dependency on automobiles and the continuing growth of private automobile ownership and use, various problems became major challenges in big cities of USA. These include traffic congestion, air pollution, road and parking infrastructure costs, energy consumption, traffic safety, fewer mobility options for the non-drivers, and a decline in the image and use of public transit. This study uses a medium sized city, Birmingham as a case study to investigate the potential of public transit to reduce automobile trips and in turn improve the overall performance of the road network by addressing the abovementioned challenges. An agent-based simulation model was developed for the Birmingham metropolitan region using the Multi-agent Transport Simulation (MATSim) platform. Three scenarios were considered with gradually increased transit ridership to identify the benefits of increased public transit. Traffic volume, network average speed, and travel times were used as performance measures for the evaluation of the designated scenarios. Results suggest that modal shifts toward public transit and reduction in travel demand for an automobile can result in improvements in speed and travel time for all users. Therefore, investments for improving transit quality and frequency of service, as well as campaigns to improve the image of public transit and make it a mode of choice for transportation users can increase transit ridership and, in turn, improve network operations, thus are deemed worthy for medium sized cities.

Scheme of Railway 5G Integrated Innovation Test Platform

An inevitable trend has already taken shape for the application of the 5th Generation Mobile Communication Technology(5G)in the railway sector.The application scenarios and business types of the railway sector are complex and diverse,so it is indispensable to test and verify the railway 5G before actual deployment.The design and creation of the railway 5G integrated innovation test platform provides engineering design,test and verification conditions for the networking,coverage and business development of 5G public networks and 5G-R in railway scenarios.This paper introduces the design of the overall architecture for the integrated railway 5G innovation test platform according to the railway network requirements,application scenarios and intelligent development trend;respectively elaborates on the design of the 5G-R core network,bearer network and wireless access along loop tracks,in combination with the characteristics of railway scenarios and the requirements of railway dispatching,operation and safety;raises further solutions on the network deployment and coverage schemes of 5G public networks so as to meet the application requirements of 5G public networks.The study results show that the integrated railway 5G innovation test platform scheme contains co-existence of 5G public and private networks,combines the indoor and outdoor scenarios,as well as takes into account of the dynamic and static tests so as to meet the environmental requirements for the integrated railway 5G test and application of all network functions,for which it can provide comprehensive technical support for railway 5G technology research and development,standard formulation,testing,etc.

空铁综合运输网络结构特征实证分析

为探究中国空铁综合运输网络结构特性,以城市为节点,若城市间有航班或高铁则连边,以航班数量和高铁数量为权重,分别建立了3个加权网络:高铁子网络、航空子网络和空铁综合运输网络。首先,通过均值关联、三角中介中心度、加权谐波中心度指标对比研究了不同网络的关键节点;其次,通过聚类系数和平均最短路径长度研究了三个网络的小世界特性;再次,通过Newman算法研究了三个网络的社团结构;最后,通过加权网络效率为指标,研究了三个网络的鲁棒性。研究结果表明,北上广深是三个网络的三种不同加权中心度的排名都很靠前,是共有的最为关键的节点。三个网络都具有小世界特性,但只有高铁子网络的模块度值大于0.3,存在明显的社团结构,并被划分为了10个社团。空铁综合运输网络具有更好的加权网络效率,约为0.32,为三个网络中最高,节点失效时的加权效率变化最小,鲁棒性最强。可见空铁综合运输网络集成了高铁网络、航空网络的互补优势,网络结构特征优于单一运输网络。

基于GIS的公交换乘网络构建及可达性分析

为了提高公交换乘效率、优化公交系统,基于GIS软件构建公交换乘网络,运用该网络对换乘可达性进行了测度和分析.结合Space-P模型和网络分析法,以拉萨市城关区为研究区域,基于公交线路路径、站点、交叉口等基本信息构建同站换乘子网络.结合公交站点服务范围、步行通道路径、交叉口等信息构建异站换乘子网络.二者协同实现了基于ArcGIS的公交换乘网络构建,并依据该网络对公交线路的乘客在车时间和换乘系数进行测度和分析.结果表明:构建的换乘网络能够对乘客在车时间进行良好的测度,乘客在车时间最大值为68.68 min,最小值为2.00 min,乘客换乘在车时间平均值为29.90 min.该换乘网络能够对换乘系数进行良好的测度,得到有效换乘线路90 300条,换乘系数最大为4条(线路为62条),最小为0条(线路为1 354条).采用可达性度量模型,可实现对公交站点时间可达性和换乘可达性的良好测度和分析.

四网融合的信号系统方案研究

城市轨道交通、市域(郊)铁路和城际铁路建设均在向网络化运营推进,各种轨道交通之间的互联互通已经是工程建设必须面临的问题,而信号系统的兼容性则是实现各种轨道交通互联互通的一个基础条件。目前,CBTC系统和CTCS列控系统在各自轨道交通领域均处于统治性的市场地位,两种列控系统对土建条件的需求截然不同,由此导致工程规模、功能定位等各方面的重大差异。重点论述两种列控系统在运营能力、公交化运营等方面的差异,针对目前互联互通所面临的技术难点,提出解决方案,为后续工程设计提供一个可行的思路。

循环神经网络模型下道路碳排放浓度预测

以湖南省永州市永州大道基本路段CO_(2)浓度时序数据为研究对象,旨在实现道路CO_(2)浓度的实时预测。测得用于模型训练和预测精度计算的路段CO_(2)浓度数据,利用Savitzky-Golay滤波器对数据进行平滑去噪,在调试并建立循环神经网络最优模型结构的基础上,引入多元预测模型(MLR、SVR、BP)和时序预测模型(BP、RF、RNN、LSTM、GRU)进行预测性能对比,为路段CO_(2)浓度的实时预测提供参照。结果表明:时序预测模型相比于多元预测模型具有更好的预测效果,特别是循环神经网络模型中的GRU表现出较高的预测精度,其次是LSTM,最后是RNN;循环神经网络模型在处理路段CO_(2)浓度时序数据的训练和预测任务中具备突出性能,能够实时且精准预测道路路段CO_(2)浓度。

四网融合条件下以客流需求为导向的市域铁路运输组织优化建议

[目的]区域一体化建设对区域多层次轨道交通网络的融合发展提出了更高的要求。在四网融合趋势下,应充分考虑客流需求,以客流需求为导向进行市域铁路的运输组织优化。[方法]从长江三角洲等区域轨道交通四网融合背景和市域铁路在其中的功能定位出发,明确了轨道交通互联互通的内涵。从客运需求总量、市域铁路客流分担率、运力供给和客运需求的匹配性3个方面阐述了当前市域铁路面临的运输组织困境。以客流需求为导向,从战略层、策略层及运营层3个层面提出了市域铁路运输组织的优化建议。[结果及结论]当前市域铁路运输组织的3大制约因素分别为线路规划建设与客运需求的差异、市域铁路与其他运输方式竞争优势不明显、缺少客流导向的列车开行方案调整机制及方法。从战略层角度应强化顶层设计,形成一体化运输组织体系;从策略层角度应化竞为合,发挥多模式轨道交通网络化效应;从运营层角度应以人为本,实行多样化行车组织模式。

交旅融合视域下重庆轨道交通公共设施数智化设计方法研究

目的致力于探索在交旅融合背景下,如何适应信息技术的快速发展,应用数智化手段提升重庆轨道交通公共设施的功能性、便捷性和用户体验等,为乘客打造一个高效、舒适且互联互通的出行环境。方法采用定量与定性相结合的研究方法。通过调查问卷收集使用群体的需求与偏好;运用层次分析法(AHP)分析重庆轨道交通公共设施,建立评价指标体系,并基于结果分析确立指标权重。结果将大数据、物联网、人工智能等数智化工具应用于重庆轨道交通公共设施中,可以帮助政府部门、轨道交通运营单位和设计师等利用科学数据全面提升服务功能和水平,精准满足乘客的功能性、文化性、情感性需求。结论探索一套适用于重庆轨道交通的公共设施数智化设计方法。该方法着眼于乘客的真实需求,兼顾科技发展趋势,有效促进重庆轨道交通公共设施的现代化改造,促进交旅融合。相关研究也为未来类似项目提供了重要的理论依据和实践指南。

低轨卫星与5G-R融合网络架构设计

由于地面网络覆盖不均匀,信号质量不够稳定,无法实现铁路交通网络的全程、快速、实时监测,阻碍了我国铁路交通网络的快速发展。同时,低轨卫星通信与地面5G的融合成为热点,二者的融合能够使卫星网络作为地面网络的有效补充。当前星地融合较少用于5G-R技术场景中。本文梳理了铁路卫星通信以及星地融合网络的研究现状与发展趋势;分析了铁路通信系统中各业务的通信需求。在此基础上,提出低轨卫星与5G-R融合网络架构。在弥补铁路通信网络覆盖盲区的同时,提供大容量的信息回传,有效保障铁路交通的安全运行,实现铁路交通的信息化、智能化管理。

一种空铁联运枢纽节点选择与分级的综合方法

空铁联运枢纽节点的选取与发展定位对构建完善合理的空铁运输网络至关重要。为此,文章基于复杂网络、熵权Topsis与系统聚类理论等提出了一种综合性评价方法,即熵权Topsis-Q型聚类法,同时全面考虑城市的运输能力与社会经济发展水平,对我国空铁联运枢纽城市的选择与分级问题进行了系统研究。首先,以36个国家级流通节点城市为研究对象,构建了有向非加权的空铁联运网络,明确并计算出反映城市运输能力的节点中心性指标。其次,进一步考虑城市社会经济发展水平指标,建立了一个三级综合评价指标体系。再次,应用熵权Topsis-Q型聚类分析法进行枢纽城市筛选与分级,最终确定出2个全国性枢纽城市和7个区域性枢纽城市。文章结论与经济、社会发展高度一致,提出的方法可用于不同模式交通枢纽节点分级评价研究。

基于LSTM神经网络的公交线路可靠性评估

公交线路可靠性是保证公交正常调度、提升乘客出行体验的前提和基础.本文将失效概率作为公交线路可靠性的评估指标,通过解析线路行程时间与可靠性之间的关联,建立基于窄界限理论的LSTM神经网络评估模型,评估宜兴市常规公交的26条线路,并进一步应用多元线性回归分析方法探究宜兴市高峰期不同站点可靠性的特点和规律.结果表明:本方法与蒙特卡洛法相比拟合速度更快,与BP神经网络模型相比,MSE降低了3.5%,MAE降低了2.9%;对公交线路站点分析发现,运营可靠性与站点所处的车道数量、路口信号灯数量、线路数量均有显著关系,车道数量与可靠性呈正相关,而路口信号灯数量、线路数量与可靠性呈负相关.

面向四网融合的大型铁路枢纽规划重点问题探讨

新时代开展面向“四网融合”的大型铁路枢纽规划是落实交通强国铁路先行规划纲要的重要工作。在解读“四网融合”内涵并剖析其对铁路枢纽规划的内在要求基础上,针对枢纽总图研究范围、枢纽总图格局、客运系统布局及分工、生产力布局、高速铁路及城际铁路引入、既有铁路资源利用等重点问题开展研究,并结合案例进行分析:在“为铁路服务”的基础上应强化“以人民为中心”“为城市服务”的规划理念;总图研究范围应逐步拓展至都市圈;总图格局应当推进“客内货外”“互联互通”;客运系统应“多点布局”,加强与国土空间规划、综合交通规划的耦合,客运站分工应“多点到发”“兼顾高普”“分向把口”;生产力布局应考虑不同层次网络资源共享;高速铁路、城际铁路应尽量实现“进城”;充分利用枢纽内铁路资源,研究利用既有铁路开行市域(郊)列车。

公交线网重构的必要性

从公交客流、公交运营成本及财政补贴三个方面介绍公交线网重构的必要性,随后介绍其他城市公交线网重构的成功经验,总结国内城市公交线网重构的方法和思路,以东莞市莞城街道公交线网优化为例,介绍了具体公交线网重构的案例和实施效果。