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891.
892.
H.-H. Braess 《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》1976,5(3):127-145
The present study is meant to prove in a theoretical way that a controlled seat movement relative to the passenger compartment will result into an improvement of passenger deceleration during vehicle frontal impacts.
This effect could be of advantage in some respects: as possible alternative for the most favourable design of the energy absorbing zones of a vehicle, as an additional safety device for the occupants of heavy vehicles with relatively soft impact absorbing zones in case of crashes against rigid obstacles, and in small vehicles where only little space exists for passenger protection.
With regard to the complexity of this subject, the study at hand must be regarded as a first step towards the final solution of the problem. 相似文献
This effect could be of advantage in some respects: as possible alternative for the most favourable design of the energy absorbing zones of a vehicle, as an additional safety device for the occupants of heavy vehicles with relatively soft impact absorbing zones in case of crashes against rigid obstacles, and in small vehicles where only little space exists for passenger protection.
With regard to the complexity of this subject, the study at hand must be regarded as a first step towards the final solution of the problem. 相似文献
893.
894.
895.
896.
R. Van Der Valk H.B. Pacejka 《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》1993,22(2):97-121
A dynamical model is presented to analyse the stability of motion of the two-wheeled 'Fokker F.28-like' landing gear including tyres. The model is equally applicable to similar landing gears. The influence of the introduction of a specially designed torsional damper on the dynamical behaviour of the landing gear-tyre combination is investigated. Results of the stability calculations are supported by test results. 相似文献
897.
A. H. Vanags 《Maritime Policy and Management》1993,20(4):319-324
Conventional wisdom has it that, because of locational and other advantages, transit trade and transport, especially maritime transport, could be expected to play a major role in the development process of the Baltic States which was expected to follow their renewed independence in 1991. This paper secks to evaluate this proposition. The first section of the paper provides a brief account of the present state of the shipping and port sectors in the three Baltic republics and offers some speculation about likely future developments. The following section considers whether there is any historical basis for the presumption in favour of transit trade. The paper concludes with a somewhat speculative discussion of whether the Baltic States might be expected to possess any long run comparative advantage in maritime transport. It is suggested that in this respect a distinction should be made between ports and shipping and that in a more prosperous future, shipping, in particular, might be expected to decline in importance. 相似文献
898.
This paper summarises work done to assess the market potential and likely financial performance of a planned high-speed rail link connecting Sydney, Canberra and Melbourne, under a variety of scenarios concerning the services offered and the possible market responses of the competing transport modes in the corridor. In the Australian context, such a link has the characteristics of an essentially new transport mode since existing rail services are extremely poorly developed. The expectation was that generated demand could be a substantial part of the overall ridership. A programme of market research was commissioned by the private consortium considering the project, designed to support forecasting models capable of predicting both diverted and generated travel on the new service. A major survey of current travellers was conducted in 1988, followed by an extensive collection of stated preference evidence about the factors affecting the travel decisions of both existing travellers and those who had not recently made any journeys in the corridor. The paper focuses mainly on the design and organisation of the surveys, on the analysis approach, and on the methods used to generate forecasts for simulated populations and scenarios. 相似文献
899.
900.
Little is known about the sources of public support for transit systems even though the perceptions of transit users and potential users have been extensively documented. Research reported here examines dimensions of public support for the first U.S. downtown people mover during three critical phases in the system's life: construction, shakedown, and operations. The method employed was a community sample survey with home interviews. Data analysis showed that the public—who were virtually all nonusers—were largely favorable toward the system during the construction phase. During the shakedown phase, when system reliability was extremely low, many attitudes toward the system became less favorable, especially perceptions of performance and direct community impacts. Later, reliability improved, and attitudes which had become less favorable tended to grow more favorable once again. It is suggested that a system's performance can influence many aspects of public support for a transit system, even among nonusers. This pattern has implications for system planners who must depend on public good will for continuing support of transit systems. In particular, extensive pretesting of new systems should occur before the fare gates are opened to patrons. 相似文献