日本高速铁路环境影响评价动态

本文介绍了日本在修建新干线时,对沿线土地利用、人口、交通、学校、文化遗址等情况的调查,着重叙述了新干线运营对环境的主要影响,特别是对地形、地质、动植物和景观等自然环境的影响,以及对环境影响评价方法和采取的对策     

对我国交直传动电力机车型谱的分析

简述了我国电力机车主要部件的标准化，简统化，系列化设计特点，分析了货运电力机车３种车型和客运电力机车５种车型的现状，表明了我国交直传动电机型谱化的必要性。     

Joint optimization of a rail transit line and its feeder bus system

A model is developed for jointly optimizing the characteristics of a rail transit route and its associated feeder bus routes in an urban corridor. The corridor demand characteristics are specified with irregular discrete distributions which can realistically represent geographic variations. The total cost (supplier plus user cost) of the integrated bus and rail network is minimized with an efficient iterative method that successively substitutes variable values obtained through classical analytic optimization. The optimized variables include rail line length, rail station spacings, bus headways, bus stop spacings, and bus route spacing. Computer programs are designed for optimization and sensitivity analysis. The sensitivity of the transit service characteristics to various travel time and cost parameters is discussed. Numerical examples are presented for integrated transit systems in which the rail and bus schedules may be coordinated.     

块石层对其下部路基土体温度的影响

块石调温路堤是多年冻土区铁路设计施工中采取的一项积极主动保护冻土的措施。本文根据野外观测资料 ,对两种不同粒径块石层下地温状况给予了初步的分析。结果表明 ,暖季粒径为 5～ 8cm的碎石层热屏蔽作用要好于片石层 ,而冷季粒径为 4 0～ 5 0 cm的片石层对流作用要强于碎石层。块石层阴阳面下地温分布具有不对称性 ,表现为阳面下地温高于阴面下的地温     

我国首台AC4000交流传动电力机车系统设计与总参数选择

论述了我国首台ＡＣ４０００交流传动电力机车方案选择与系统设计的基本原则，了选择电压型交直交变流器供电的异步机系统作为电力传动装置的优越性。介绍了机车总参数，运行特 及其电路结构与原理。     

电磁兼容性试验室的设计要求

汇集ＩＥＣ、ＣＩＳＰＲ等电磁兼容性试验标准的要求，提出适用于变流行业特别是机车变流器、机车电气设备及电子装置的电磁兼容性试验室的建设方案。     

An artificial neural network approach for evaluating transportation network improvements

As demand increases over time, new links or improvements in existing links may be considered for increasing a network's capacity. The selection and timing of improvement projects is an especially challenging problem when the benefits or costs of those projects are interdependent. Most existing models neglect the interdependence of projects and their impacts during intermediate periods of a planning horizon, thus failing to identify the optimal improvement program. A multiperiod network design model is proposed to select the best combination of improvement projects and schedules. This model requires the evaluation of numerous network improvement alternatives in several time periods. To facilitate efficient solution methods for the network design model, an artificial neural network approach is proposed for estimating total travel times corresponding to various project selection and scheduling decisions. Efficient procedures for preparing an appropriate training data set and an artificial neural network for this application are discussed. The Calvert County highway system in southern Maryland is used to illustrate these procedures and the resulting performance.     

Estimating the demand for urban bus travel

The disadvantages of conventional transportation study models, in particular their large data requirements and their weaknesses in dealing with changes in trip generation rates have led to a need for a simple model that can quickly and at low cost examine alternative public transport strategies.This paper investigates simple economic models of bus demand, examines alternative variables that can be used and discusses some alternative model forms. It demonstrates the results of a model using data from twelve urban bus operators in Britain and compares the results with those from other types of study. The model utilises fare and service quality elasticities to explain the decline in passengers on urban bus services, and derives an average elasticity with respect to fare changes of –0.31 and with respect to service quality changes of +0.62. It is estimated that fare rises accounted for 13% of the 43% decline in passengers over the last fifteen years, vehicle mileage reductions for 14.3% and that only 15.7% was due to such factors as rising car ownership which are often given as the cause of declining bus patronage.The results, by showing that passengers are far more sensitive to changes in service than they are to fare rises, are a useful guide to the broader public transport policy issues, and the paper concludes that the model does provide a useful method of forecasting public transport demand at a strategic level. Further work is needed, however, to establish more accurate forecasts for different types of passenger and studies are now being undertaken to establish these and to construct an operational forecasting model that can be applied with only limited data requirements     

长隧道电力牵引高压工频电磁场的卫生学评价

对我国长隧道的电力牵引27.5kV50Hz电磁场的分布状况及其规律进行了实测和论述,其均值电场强度为2.01±1.01kV/m,磁感应强度为0.21±0.23mT,人体感应电流为17.18±9.51μA,各项指标均以接触网下及复线钢轨间的强度高,两侧人行道低,且比隧道外明显降低,各点3项指标均值均在我国及国外规定或建议容许值之内,为全面制订长隧道运营维护方面的防护措施提供了依据。