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21.
城市对外交通中,铁路是发展较早的交通运输方式。本文以新疆的铁路交通网络为依据,以道路密度为指标,利用Arc GIS的叠加分析和空间分析功能,研究新疆铁路交通网络的空间分异,并分析新疆各区域人口、生产总值差异与铁路密度差异之间的相互关系。结果表明:(1)新疆铁路密度差异显著,大体呈现"南北低中部高"的趋势;(2)新疆各地区铁路密度与人口分布、生产总值高度正相关。 相似文献
22.
铁路物流园区相关特性的研究 总被引:1,自引:0,他引:1
通过对物流园区概念和模式的论述,分析了铁路物流园区的特点和分类,并结合我国既有铁路物流园区存在的缺乏规划和定位不准等问题,对铁路物流园区建设规划和运作方法进行了探讨,提出确保铁路物流园区健康发展的建议。 相似文献
23.
铁路与经济发展之间的关系得到了大量的研究,但均集中于短期经济影响,且很少关注铁路在发展中国家从传统农业社会向工业社会转型过程中的作用。文章使用中国1980年的铁路线研究了铁路在中国转型期对县域经济发展的长期影响。研究发现,铁路开通对县域经济发展具有显著的长期促进作用,具体来说,以2000年数据为例,1980年铁路线对以GDP为衡量指标的经济发展的年均促进作用为1.16%。排除了无法观测因素和溢出效应、控制县级异质性、以及使用"三线建设"作为外生冲击的结果均支持上述结论。机制检验发现,铁路促进了县域层面的工业化,同时还显著增加了县域层面的外商投资和出口,进而促进了经济发展。本文的研究不仅提供了铁路的长期经济影响的经验证据,同时也揭示了以铁路为代表的基础设施对经济转型的作用,从而有助于理解中国经济增长奇迹,也为其他发展中国家转型提供了借鉴。 相似文献
24.
帽梁施工采用无支架法施工相对满堂支架法施工而言,具有施工简便,对地面承载力无要求,节约大量钢管,降低施工成本,缩短工期等优点。文章针对洛湛铁路旺甫1号三线大桥设计出穿心棒无支架法施工帽梁的支撑系统方案,成功地解决了三线大桥因帽梁砼重量大、跨度长而致使常用材料不适合做承托梁的问题,并对支撑系统进行了受力检算。 相似文献
25.
中国高速铁路客运产品设计 总被引:2,自引:0,他引:2
以形成完整的中国高速铁路客运产品设计方法体系为目标,从分析客运产品层次及要素出发.提出客运产品设计原则与总体思路。研究客运产品的设计方法,从可达性、时效性、便捷性和经济性四方面研究列车开行方案设计及调整,从自助式、人性化、差异化等六方面研究服务产品设计,并提出中国高速铁路品牌战略。 相似文献
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27.
Understanding the cascade dynamics of delay propagation under inclement weather is crucial to proactive railway management. In this paper, we proposed a Switching Max-Plus System (SMPS) to model the delay propagation on railway networks, which extends the conventional MPS by incorporating multiple system matrices to capture the dynamic impacts of inclement weather. An algorithm based on the All-Paired Critical-Path (APCP) graph was developed to solve the SMPS, which calculates secondary delays without backtracking the precedent events. The proposed model and its solution algorithm were validated using discrete-time simulations on both artificial and empirical networks. The robustness of railway services was also analyzed using the concepts of vulnerability and diffusivity. 相似文献
28.
Two fundamental mathematical formulations for railway timetabling are compared on a common set of sample problems, representing both multiple track high density services in Europe and single track bidirectional operations in North America. One formulation, ACP, enforces against conflicts by constraining time intervals between trains, while the other formulation, RCHF, monitors physical occupation of controlled track segments. The results demonstrate that both ACP and RCHF return comparable solutions in the aggregate, with some significant differences in select instances, and a pattern of significant differences in performance and constraint enforcement overall. 相似文献
29.
This paper proposes an accessibility-based spatial mixed logit (SML) model with panel data structure to examine the impacts of High-Speed Rail (HSR) on land cover change in large urban areas. Using data between 1990 and 2006, impacts of the Spanish HSR on Madrid’s Atocha railway station influence area – a 20 km radius buffer centred on the station – were investigated. To model the HSR impacts, besides socioeconomic variables, the development of both local and regional transportation networks with corresponding accessibility improvement is also taken into account to segregate the impacts of land-cover change brought by different sources of accessibility measures. In this study, two SML models are used: one incorporates regional accessibility indicators as a base model, and the other does not, acting as a control model. The model estimation results reveal that the reduction of the local and regional weighted travel average time has positive impacts on the Atocha station catchment area’s urbanised land-cover rates. Although the base and control models both achieve high goodness-of-fit values, the base model that considers regional accessibility reveals a better goodness-of-fit statistic and is more robust than the control model. It is concluded that the improvement of regional accessibility due to the arrival of HSR at Atocha station plays an essential role in the urbanisation of land cover changes in the study area. 相似文献
30.
George Hudson was the most important railway promoter of his time. He had a particular aptitude for visualizing and arranging spectacular company and line amalgamations and his activities helped to bring about the beginnings of a more modern railway network. In 1849 he exercised effective control over nearly 30 per cent of the rail track then operating in the UK, most of it owned by four railway groups, the Eastern Counties Railway, the Midland, the York, Newcastle and Berwick, and the York and North Midland, before a series of scandalous revelations forced him out of office. The economic, railway and accounting literatures have treated George Hudson as an important figure in railway history, although concentrating largely on the financial reporting malpractices of the Eastern Counties Railway, while Hudson was its chairman, which were incorporated into the influential Monteagle Committee Report of 1849. Relatively little attention has been paid, however, to events at Hudson's other major companies. This paper analyzes the available evidence, particularly that produced by the Committees of Investigation established at all four railway groups, in order to provide a more balanced assessment of George Hudson's approach to financial reporting and thereby place events at the Eastern Counties Railway in a broader context. 相似文献