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1.
This paper presents an approach to include both the unstorable feature of transportation service and the technological differences within railway companies in efficiency and effectiveness measurements. We explore efficiency and effectiveness for a group of 40 global railways in the year 2002, using traditional data development analysis (TDEA) and network data development analysis (NDEA). Comparing the results obtained from the NDEA model with those from the TDEA indicate that performance measures are quite different in terms of the magnitude, and even using different DEA type models to evaluate railway system performance does not distort the ranking of their performance. We also analyze the inter-related effects among three performance measures, finding that transportation service characteristics have positive effects on the evaluation of performance. Generally speaking, the NDEA model provides deeper insight regarding the sources of inefficiency and process-specific guidance to railway managers so as to help them improve their railway’s performance.  相似文献   

2.
当前铁路隧道施工亟待解决的若干技术问题   总被引:1,自引:0,他引:1  
高速铁路隧道工程建设标准高,施工难度大,安全风险高,施工管理要求严格。文章以贵广铁路隧道工程为实例,结合当前国内隧道施工技术现状和贵广铁路隧道创新技术的现场实践,研究分析了制约隧道施工安全和施工效率的突出技术问题,取得了一系列研究成果:①基于精细爆破技术的微台阶开挖工艺可有效解决IV、V级围岩隧道开挖进度与工序安全距离之间的矛盾;②得益于通风技术和空气净化技术的进步,无轨运输方式可以适应于长大隧道的施工;③隧道仰拱快速施工设备和隧道沟槽移动模架的开发应用填补了这一领域的空白;④信息化施工是未来隧道施工技术发展的大趋势。  相似文献   

3.
This paper examines various regulatory methods for congested urban railways. After building a closed spatial model with a congestible railway line, we conduct a numerical simulation of the impacts of the regulatory methods, using data on a typical railway firm in Japan. A closed spatial model in this paper enables us to evaluate the regulatory methods in terms of social welfare as well as to show a change in the typical performance of railways, such as the level of fares, railway capacity, and congestion. The simulation results show that implementing simple price-cap regulation, without properly addressing the congestion problem, makes railway firms operate efficiently, but substantially shrinks railway capacity and lowers social welfare. We then consider modified versions of price-cap regulation, which are consistent with relief of congestion.  相似文献   

4.
Noise and vibration are two of the main problems associated with railways in residential areas. To ensure quality of life and well-being of inhabitants living in the vicinity of railway paths, it is important to evaluate, understand, control and regulate railway noise and vibration. Much attention has been focused on the impact of noise from railway traffic but the consideration of railway-induced vibration has often been neglected. This paper aims to provide policy guidance based on results obtained from the analyses of relationships estimated from ordinal logit models between human response, railway noise exposure and railway vibration exposure. This was achieved using data from case studies comprised of face-to-face interviews (N = 931), internal vibration measurements (N = 755), and noise calculations (N = 688) collected within the study “Human Response to Vibration in Residential Environments” by the University of Salford, UK. Firstly, the implications of neglecting vibration in railway noise policies are investigated. The findings suggest that it is important to account for railway induced vibrations in future noise and transport policies, as neglecting vibrations results in an underestimation of people highly annoyed by noise. Secondly, implications of neglecting different types of railway sources are presented. It was found that the impact of noise and vibration form maintenance operations should be better understood and should be taken into account when assessing the environmental impact of railways in residential environments. Finally, factors that were found to influence railway vibration annoyance are presented and expressed as weightings. The data shows that factors specific to a particular residential area should also be taken into account in future vibration policies as the literature shows that attitudinal, socio-demographic and situational factors have a large influence on vibration annoyance responses. This work will be of interest to researchers and environmental health practitioners involved in the assessment of vibration complaints, as well as to policy makers, planners and consultants involved in the design of buildings and railways.  相似文献   

5.
Reform of trucking Vehicle Weights and Dimensions (VWD) regulations in Canada is now underway. The effect these reforms will have on the freight transportation industry are only recently the subject of research. This paper is part of this new research effort, aimed at understanding how regulatory reform in the trucking sector will affect the existing competitive relationship between trucks and the railways. The paper presents the results of study and research into modelling the relationship between mode choice and the service characteristics that are affected by VWD reform.Using several periods of data, a series of econometric models are developed which help to elucidate the relative relationships between the mode service characteristics for both of the principal interprovincial freight modes. A technique is developed and presented to model railway user costs in order to overcome the complex and often unrepresentable pricing activities of Canadian railways.The strength of the developed econometric models is presented, including their significance and statistical reliability. This is further reinforced by the similarities exhibited by all the models in the series. The selected model is applied to predict market service responses required of the railway industry in order to compete with the trucking sector now adapting to the new regulations.The impact of the newly implemented vehicle weight and dimension reform on the rail transportation industry is analyzed and railway industry improvements aimed at maintaining its market share are presented. The results predicted by the model show that railway user cost reductions should be moderate, and likely less than the level of inflation over the period of time when trucking converts its fleet to take advantage of the new regulations.Abbreviations AASHTO American Association of State Highway and Transportation Officials - CCMTA Canadian Conference of Motor Transport Administrators - EPI End products, inedible commodity classification - GVW Gross Vehicle Weight - NA 1988 VWD National Agreement - RTAC Roads and Transportation Association of Canada - VWD Vehicle Weight(s) and Dimension(s) - WA 1988 VWD Western Agreement  相似文献   

6.
铁路运输在国民经济运行中发挥着重要作用,各国铁路公司都非常重视对铁路运营、安全、效益的管理及评价。国外铁路经过两个世纪的发展,积累了丰富经验,通过分析美国、日本、欧洲等国家和地区的普速、高速铁路,在运营效率评价、运营安全评价、服务质量评价、经营效益评价、安全保障法律法规建设和第三方评价机构发展等方面的现状,从客户服务质量评价、安全评价标准体系建立、效率效益导向的经营效益评价机制建设、第三方专业评价机构发展等维度,总结对我国高速铁路运营安全效益评价的经验借鉴及启示。  相似文献   

7.
文章分析了城际高速铁路的特点和功能,阐述了交通产业结构的基本属性和发展趋势。并结合我国第一条城际铁路——京津城际铁路建成后对周边产业结构的实际影响效果,从交通产业结构优化的角度分析发展城际铁路的意义。  相似文献   

8.
This work presents an intelligent system which allows the detection of obstacles on railways. The sensory system is based on one barrier of infrared emitters and another of receivers, placed on opposing sides of the railway. Obstacle detection is achieved by a lack of reception in the detectors. The efficiency of the system is improved with the geometrical distribution of the sensory system and the encoding used at the emitting and receiving stages. Additionally optimal estimation techniques have been proposed to avoid false alarms, based on Kalman and H∞ filtering. Furthermore, Principal Component Analysis is applied to validate the obstacle detection, and to improve the efficiency of the system. A high reliability under adverse conditions is obtained with the barrier, it now being possible to detect the presence of obstacles, and to report on their position.  相似文献   

9.
瓦斯隧道施工控制及防治措施探讨   总被引:1,自引:0,他引:1  
"十二五"规划提出每年投入7000亿修建铁路,隧道占很大比例,其中施工遇到的瓦斯隧道越来越多.文章以兰渝铁路13标段瓦斯隧道群的施工实践为例,探讨了瓦斯隧道的特征和危害,并提出隧道瓦斯的预测、检测和防治措施,以及防爆设备的防爆改装依据和改装项目,可供同类工程借鉴.  相似文献   

10.
11.
In the US, freight railways are one of the major means to transport goods from ports to inland destinations. According to the Association of American Railroad’s study, rail companies move more than 40% of the nation’s total freight. Given the fact that the freight railway industry is already running without much excess capacity, better planning and scheduling tools are needed to effectively manage the scarce resources, in order to cope with the rapidly increasing demand for railway transportation. This research develops optimization-based approaches for scheduling of freight trains. Two mathematical formulations of the scheduling problem are first introduced. One assumes the path of each train, which is the track segments each train uses, is given and the other one relaxes this assumption. Several heuristics based on mixtures of the two formulations are proposed. The proposed algorithms are able to outperform two existing heuristics, namely a simple look-ahead greedy heuristic and a global neighborhood search algorithm, in terms of railway total train delay. For large networks, two algorithms based on the idea of decomposition are developed and are shown to significantly outperform two existing algorithms.  相似文献   

12.
地铁盾构区间穿越铁路站场设计与施工分析   总被引:1,自引:0,他引:1  
文章以郑州地铁1号线火车站站至二七广场站盾构区间隧道为背景,对隧道施工中的特级风险源——区间下穿国铁站场路段的施工过程进行了三维仿真数值模拟。按照国家相关规范标准,两轨面间的差异沉降不得大于5 mm,这对地铁下穿段的施工提出了较高要求。数值模拟计算结果表明,通过对下穿段一定范围内的土体进行注浆加固,可以有效控制盾构隧道施工引起的既有铁路纵向和横向沉降及不均匀沉降,从而保证既有铁路的运营安全。  相似文献   

13.
With a large number of railway development projects in Europe and worldwide, which once completed will be serving rail passengers of the future, this paper aims to take a step back and evaluate current railway systems performance. The objectives are to compare statistical data on various passenger-related parameters of the railway system in a number of selected European countries and draw conclusions on the level of their performance when compared to the European average.Analyses of publically available statistical data, extracted from the Eurostat service at a European level will allow for a comparison of various indicators which influence the performance of the railway systems from an infrastructure and operational perspectives. The analyses will also allow identifying key performance indicators for the accurate assessment of the rail systems.The paper will highlight case studies for various parameters which are important to stakeholders of the railways, including infrastructure managers, rail operators, policy makers and the end users. This knowledge will be to the benefit of today’s railway industry as well as the rail systems of the future, as it will show trends drew upon existing data which might continue in the future.  相似文献   

14.
客运专线耐久性混凝土对骨料的指标要求及原因浅析   总被引:1,自引:0,他引:1  
客运专线施工中的混凝土配制要求采用耐久性混凝土,而经验和实践证明优质骨料是配制耐久性混凝土的关键因素;客运专线标准也都对骨料的质量指标提出了很高的要求.文章通过对现行规范和验标的解读,分析了优质骨料在优质耐久性混凝土中的作用机理.  相似文献   

15.
The development of railway transportation, especially through the gradual implementation of high-speed European network, is inciting railway companies to design railway movements command and control systems to enhance technical performance in terms of throughput and control of disturbances while simultaneously minimizing operational costs. The new command-control systems must be modular, adaptable and evolutive structures from both functional and geographical viewpoints if they are to satisfy all operational needs. Concurrent research into performance enhancement and cost reduction prescribes a system in which the majority of the “real time” components are aboards the locomotives. This is particularly true for those components used by the train to indicate its own position on the network as well as those enabling it to converse with operational control centers. The initial task is to design a global architecture of the command-control system that satisfies modularity and availability criteria followed by the development of numerous technical components including radar self-location systems and cellular radio transmission networks. The French (SNCF) and German (DB) national railways have implemented a vast program of co-operation aimed at providing valid, proven answers to these problems so as to allow their trains to travel freely on either network.  相似文献   

16.
Planning and operating railway transportation systems is an extremely hard task due to the combinatorial complexity of the underlying discrete optimization problems, the technical intricacies, and the immense size of the problem instances. Because of that, however, mathematical models and optimization techniques can result in large gains for both railway customers and operators, e.g., in terms of cost reductions or service quality improvements. In the last years a large and growing group of researchers in the OR community have devoted their attention to this domain developing mathematical models and optimization approaches to tackle many of the relevant problems in the railway planning process. However, there is still a gap to bridge between theory and practice (e.g. Cacchiani et al., 2014; Borndörfer et al., 2010), with a few notable exceptions. In this paper we address three individual success stories, namely, long-term freight train routing (part I), mid-term rolling stock rotation planning (part II), and real-time train dispatching (part III). In each case, we describe real-life, successful implementations. We will discuss the individual problem setting, survey the optimization literature, and focus on particular aspects addressed by the mathematical models. We demonstrate on concrete applications how mathematical optimization can support railway planning and operations. This gives proof that mathematical optimization can support the planning of railway resources. Thus, mathematical models and optimization can lead to a greater efficiency of railway operations and will serve as a powerful and innovative tool to meet recent challenges of the railway industry.  相似文献   

17.
The operations of European railway companies are generally confined to the territory of one country. Each company incurs the cost of operations on its network. For international trains there are systems of physical compensation for vehicles and staff operating outside their home network. Revenues either go direct to each company involved, or, in the case of through international rates, are apportioned according to distance. This situation implies that for any decision on price and services agreement of all operators involved is necessary. Also, the apportionment of costs between operators is not in line with real cost structure. With further integration in the European community, and freer movement between Eastern and Western Europe, international transport will become more important, and railways will be at a disadvantage compared with other modes that can operate international services throughout. An organisation is proposed and illustrated with some examples, wherein separate commercial units are formed responsible for running and marketing an international rail service. Track, vehicles, and staff of national railway companiew may be used as now, but at a price to be agreed, and without the need for physical compensation.  相似文献   

18.
The paper develops a model to represent the cost structure of European railways based on a general index of technical change, which allows completely general estimation of productivity growth. The estimated model is based on a variable cost function for panel data, which allows for heterogeneity in spite of previous approaches in the railway economics and general index model literature which adopt the assumption of common technical parameters across countries.  相似文献   

19.
随着集装箱物流的发展,部分既有铁路要改造为双层集装箱运输通道,然而既有铁路的隧道限界大多为隧限-2,不能满足双层集装箱运输隧道建筑限界。文章通过对限界、接触网悬挂方式及隧道处理措施等方面的研究,提出了隧限-2B隧道通行双层集装箱列车是可行的结论。  相似文献   

20.
随着“一带一路”设施联通建设的不断推进,作为泛亚铁路中线工程的中老泰铁路也是其中重要的一部分。为研究一带一路中老泰铁路货物运输风险以及相关保费计算,本文首先采用层次分析法得到铁路货物运输过程中存在的政治因素、气候因素、运维因素和自然力因素的风险以及不同风险因素组合的权重;其次基于N-K模型对风险进行耦合,并且结合权重计算风险耦合值,根据风险耦合值划分风险区间,不同风险区间对应的附加费率不同,最后利用保费计算公式可以得到保险费用。本文末以中老泰铁路运输水果为例,基于不同风险因素的耦合得到15个风险耦合值,并计算保费,得出不同风险下的保费结果。  相似文献   

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