为满足铁路网区间运输能力可视化决策的需求,以及铁路枢纽紧张区段日常分析要求,基于地理信息系统(GIS,Geographic Information System)、大数据技术,设计了集铁路运行线、经营、客票、货票、计划、统计等多源运输数据信息为一体的铁路...为满足铁路网区间运输能力可视化决策的需求,以及铁路枢纽紧张区段日常分析要求,基于地理信息系统(GIS,Geographic Information System)、大数据技术,设计了集铁路运行线、经营、客票、货票、计划、统计等多源运输数据信息为一体的铁路网能力利用分析系统。提出了面向高速铁路、普速铁路的实际通过能力计算方法,以及融合客/货运密度、客座利用率的计算方法;构建了标准统一的时空信息关联模型,将多源数据信息与GIS数据进行融合,实现了铁路网运输能力的可视化表达、多维统计、智能检索、一省一图、车站到发量分析等功能。试点应用表明,该系统能够显著提升面向铁路网的分析能力,减少数据维护工作量,对改善铁路运输能力提供信息化支撑。展开更多
According to the railway transportation system＇s characteristics, a new cellular automaton model for the single- line railway system is presented in this paper. Based on this model, several simulations were done to i...According to the railway transportation system＇s characteristics, a new cellular automaton model for the single- line railway system is presented in this paper. Based on this model, several simulations were done to imitate the train operation under three working diagrams. From a different angle the results show how the organization of train operation impacts on the railway carrying capacity. By using the non-parallel train working diagram the influence of fast-train on slow-train is found to be the strongest. Many slow-trains have to wait in-between neighbouring stations to let the fast-train（s） pass through first. So the slow-train will advance like a wave propagating from the departure station to the arrival station. This also resembles the situation of a highway jammed traffic flow. Furthermore, the nonuniformity of travel times between the sections also greatly limits the railway carrying capacity. After converting the nonuniform sections into the sections with uniform travel times while the total travel time is kept unchanged, all three carrying capacities are improved greatly as shown by simulation. It also shows that the cellular automaton model is an effective and feasible way to investigate the railway transportation system.展开更多
The problems of fast determining shortest paths through a polygonal subdivision planar with n vertices are considered in GIS. Distances are measured according to an Euclidean metric. A geographical information system ...The problems of fast determining shortest paths through a polygonal subdivision planar with n vertices are considered in GIS. Distances are measured according to an Euclidean metric. A geographical information system (GIS) has a collection of nearest neighborhood operations and this collection serves as a useful toolbox for spatial analysis. These operations are undertaken through the Voronoi diagrams. This paper presents a novel algorithm that constructs a' shortest route set' with respect to a given source point and a target point by Voronoi diagrams. It will help to improve the efficiency of traditional algorithms, e. g., Djkstra algorithm, on selecting the shortest routes. Moreover, the novel algorithm can check the connectivity in a complex network between the source point and target one.展开更多
文摘为满足铁路网区间运输能力可视化决策的需求,以及铁路枢纽紧张区段日常分析要求,基于地理信息系统(GIS,Geographic Information System)、大数据技术,设计了集铁路运行线、经营、客票、货票、计划、统计等多源运输数据信息为一体的铁路网能力利用分析系统。提出了面向高速铁路、普速铁路的实际通过能力计算方法,以及融合客/货运密度、客座利用率的计算方法;构建了标准统一的时空信息关联模型,将多源数据信息与GIS数据进行融合,实现了铁路网运输能力的可视化表达、多维统计、智能检索、一省一图、车站到发量分析等功能。试点应用表明,该系统能够显著提升面向铁路网的分析能力,减少数据维护工作量,对改善铁路运输能力提供信息化支撑。
文摘According to the railway transportation system＇s characteristics, a new cellular automaton model for the single- line railway system is presented in this paper. Based on this model, several simulations were done to imitate the train operation under three working diagrams. From a different angle the results show how the organization of train operation impacts on the railway carrying capacity. By using the non-parallel train working diagram the influence of fast-train on slow-train is found to be the strongest. Many slow-trains have to wait in-between neighbouring stations to let the fast-train（s） pass through first. So the slow-train will advance like a wave propagating from the departure station to the arrival station. This also resembles the situation of a highway jammed traffic flow. Furthermore, the nonuniformity of travel times between the sections also greatly limits the railway carrying capacity. After converting the nonuniform sections into the sections with uniform travel times while the total travel time is kept unchanged, all three carrying capacities are improved greatly as shown by simulation. It also shows that the cellular automaton model is an effective and feasible way to investigate the railway transportation system.
文摘The problems of fast determining shortest paths through a polygonal subdivision planar with n vertices are considered in GIS. Distances are measured according to an Euclidean metric. A geographical information system (GIS) has a collection of nearest neighborhood operations and this collection serves as a useful toolbox for spatial analysis. These operations are undertaken through the Voronoi diagrams. This paper presents a novel algorithm that constructs a' shortest route set' with respect to a given source point and a target point by Voronoi diagrams. It will help to improve the efficiency of traditional algorithms, e. g., Djkstra algorithm, on selecting the shortest routes. Moreover, the novel algorithm can check the connectivity in a complex network between the source point and target one.
