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51.
This paper presents an off‐line forecasting system for short‐term travel time forecasting. These forecasts are based on the historical traffic count data provided by detectors installed on Annual Traffic Census (ATC) stations in Hong Kong. A traffic flow simulator (TFS) is developed for short‐term travel time forecasting (in terms of offline forecasting), in which the variation of perceived travel time error and the fluctuations of origin‐destination (O‐D) demand are considered explicitly. On the basis of prior O‐D demand and partial updated detector data, the TFS can estimate the link travel times and flows for the whole network together with their variances and covariances. The short‐term travel time forecasting by O‐D pair can also be assessed and the O‐D matrix can be updated simultaneously. The application of the proposed off‐line forecasting system is illustrated by a numerical example in Hong Kong. 相似文献
52.
53.
M.W. Sayers 《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》1991,20(5):297-308
Vehicle offtracking behavior at low speeds is closely approximated by a geometric entity called a tractrix. This paper presents differential equations for generalized coordinates of a planar multibody vehicle model based on tractrix behavior. The equations are exact, can be used with any type of input path, are valid for forward and backward movements, and are much simpler than previously published formulations used to compute transient offtracking. The differential equations can be integrated using conventional numerical integration algorithms to obtain plots of the low-speed tracking performance of articulated vehicles. The equations were formulated symbolically by a computer program used to analyze the kinematic and dynamic behavior of multibody systems. Example numerical results are plotted. 相似文献
54.
阿尔斯通开发的PRIMA 3U15型电力机车 总被引:3,自引:0,他引:3
王渤洪 《变流技术与电力牵引》2005,(3):43-49
阿尔斯通公司运输部开发了PRIMATM机车系列,其类型满足了运营部门提出的模块化和系列化要求.投放欧洲市场的PRIMA型电力机车既满足了通用性要求,又有助于与公路的经济竞争取得成效.为此,阿尔斯通公司继法国双流制机车后又开发了一种三流制机车,该型机车可用于法国、德国和瑞士之间的跨境运输.文章介绍PRIMATM系列的开发过程以及得到法国国家铁路的订单.详细叙述了PRIMA 3U15型三流制机车,重点是PRIMA电力机车的维修、可靠性和可用性. 相似文献
55.
Over the past decade, the escalating roadway congestion and environmental deterioration due to heavy use of private vehicles
have provoked the Taiwan government to realize the importance of public transport systems. Under the “carrot-and-stick” rationales,
the government has formulated public transport policies and exercised a series of related initiatives by providing sufficient
and higher quality of public transport services so as to attract more private vehicle users. In this paper, the planning philosophy
and policy formulation of Taiwan’s public transport development are highlighted. The most important initiatives, including
the Five-year Enhancement of Mass Transportation Program and the upgrading public transport schemes in the National Development
Plan are examined. Based on previous experience and lessons, we point out the most challenging issues that the government
will encounter. Suggestions for the future of public transport planning are also addressed. 相似文献
56.
Y. Hattori K. Asano N. Iwama T. Shigematsu 《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》1995,24(4):299-311
This report describes a decelerating driver-model expressed by driving mode transition in car-following situations. The assumptions for constructing the model are that decelerating strategy of a driver is classified into several simple driving modes and that a driver changs his driving modes based on his perceptible characteristics and experiential rules. Deceleration action is divided into three states; following, standing and braking, which are applied to the model. The model has two paths for driver's decelerating action, one of which is selected by the driver based on the perceptible characteristics and experiential rules. The suitability of the model has been experimentally verified. 相似文献
57.
N. Docquier P. Fisette H. Jeanmart 《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2007,45(6):505-524
This article presents a multidisciplinary approach of railway pneumatic suspension modelling: both multibody and pneumatic aspects are taken into account. The work aims at obtaining a realistic model of the secondary suspension and coupling it with a multibody model of a train. Various components of the pneumatic circuit such as bellows, tanks, pipes and valves are taken into account. The article focuses on the bellow-pipe-tank subsystem for which several modelling approaches are presented and compared. Differences between differential and algebraic models are highlighted, and an application-dependent choice between them is suggested. A complete model of the pneumatic circuit is then obtained and coupled with a multibody model of the train. As a result, the behaviour of a suburban train equipped with a pneumatic secondary suspension is analysed, in particular undesired oscillating motions which affect the comfort. Topological modifications and improvements of the suspension are also investigated and discussed. 相似文献
58.
腹地经济发展对港口吞吐量影响的动态研究 总被引:8,自引:2,他引:6
腹地经济规模和经济结构的变化影响着港口的发展方向,但是一般的静态回归模型中解释变量参数是固定的,无法反应腹地各种影响因素变化对港口吞吐量产生的动态影响,而变参数状态空间模型克服了这一缺陷,解释变量的参数可以随时间改变,充分体现了解释变量对因变量影响关系的改变,因此能够更加准确反映考察期内腹地各种因素对港口吞吐量的动态影响。在介绍模型的基础上,就东北经济对大连港集装箱吞吐量影响进行了实证研究,得出了较为详尽的结论,这些结论是港口未来发展的重要决策依据。 相似文献
59.
王志恩 《西安交通大学学报(英文版)》1995,(2)
T_H1ANDT_H2CELLANTIGENRECEPTORSINEXPERIMENTALLEISHMANIASISStevenL.Reiner,WangZhi'en;FarahHatam,PhillipScott,RichardM.Locksley(... 相似文献
60.
The work described was undertaken as part of the CASSIOPE project in the EC DRIVE programme. A range of fare collection procedures in public transport is described, and the importance of these for data collection by operators is stressed. It is suggested that such data management could be standardized and to this end four case studies were carried out in different European cities. Data models were built for each city, and these models are merged into a preliminary version of a generalized model. The need and uses for such a fare collection data model is explained. 相似文献