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351.
Active control systems offer significant functional advantages over passive systems; their introduction into production-line vehicles, however, is cautious and slow. This survey describes the recent progress in the analysis, design and technology of active controls in vehicles. It includes the state-of-the-art of their introduction into operation as well as their future potential in view of recent advances in technology and computer aided design strategies. The survey has been limited to suspensions for vehicles on roads and tracks.  相似文献   
352.
Agricultural tractors are relatively slow moving vehicles but a good steer response under all working conditions is generally required. This paper evaluates the effect of ground slope, axle load, ground speed, tyres and ground surface on yaw rate response to steer input.  相似文献   
353.
This brief paper examines some of the problems of interpretation of documents and procedures given in English faced by non-English seafarers, and suggests the use of 'controlled' English to simplify these problems.

' Speak English ', said the Eaglet, ' I don't know the meaning of half those long words, and what's more, I don't believe you do either. '

Alice's Adventures in Wonderland

Lewis Carroll  相似文献   
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357.
This paper examines the competitiveness of selected eastern Canadian ports for the handling of foreign cargoes in terms of macroeconomic and geographic factors.  相似文献   
358.
With the publication of the Sydney Area Transportation Study, land-use/transportation studies now have been conducted in all capital cities as well as in the majority of other urban areas with populations in excess of 40.000. A review of these studies is made and a qualitative assessment is attempted of the technical phases —land-use planning, trip-generation, trip-distribution, modal-split, traffic assignment and evaluation. Full summary results of this comparative survey are presented in tabular form, although themes developed in the text are illustrated with specific examples from individual studies. The methodology of land-use/transportation studies has been attacked by some Australian writers. An attempt is made to assess the relevance of these criticisms when applied to the practical planning process in Australia.  相似文献   
359.
Non-Contact Suspension and Propulsion Technology   总被引:3,自引:0,他引:3  
As a result of extensive research and development in several countries, the technologies of magnetic suspension and linear electric drives are becoming available for transportation applications. The successful demonstration and operation of prototype vehicles has established the technical viability of these systems. Several urban transit or shuttle services, with magnetic suspension and/or linear motor propulsion are likely to be operational within 3-4 years. After the final stages ofdevelopment and rigorous testing, high speed systems are likely to be an option for intercity implementation by the end of the decade. This paper presents a report on the worldwide status of R&D and test programs of non-contact suspension and propulsion technology for guided ground transport.  相似文献   
360.
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