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91.
92.
H. E. Tseng 《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2001,36(4):307-328
Road bank angles have a direct influence on vehicle dynamics and lateral acceleration measurement. A vehicle stability control system that knows road bank angle has an advantageous capability in achieving desired control sensitivities for maneuvers on ice and snow, among all surfaces, while avoiding false/nuisance activation on a banked road. Since neither lateral velocity nor road bank angle are directly measurable in current vehicle systems due to economical reasons, the major challenge is to differentiate the bias induced by road bank disturbances from actual effect of vehicle lateral dynamics in current measurements. This paper proposes a method of road bank estimation and provides theoretical background for the decoupling effort of lateral dynamics and road disturbances involved in bank estimation. 相似文献
93.
H. Minamoto S. Takezono 《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2000,34(4):229-248
This paper deals with two-dimensional motion analysis of vehicles damaged due to collision. Various parts of vehicles are damaged due to collision in general. The effects of the damage in vehicle body and wheels on the vehicle motions are investigated. The center of gravity of the vehicle and the polar moment of inertia are changed by the deformation of vehicle body. Furthermore, the geometrical relations of wheels like wheelbase, treads and steering angles may be changed by damage of the wheels. Thus the vehicle loses symmetry with respect to the vehicle axis. The four-wheel vehicle model is extended to take into account the vehicle damage due to collision. The motions of damaged vehicles are compared with those of undamaged vehicles. It is found that vehicle damages have a significant influence on vehicle motion after impact. 相似文献
94.
H.K. Sachs 《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》1972,1(3):161-177
The influence of vehicle handling on the possible avoidance of accident situations is discussed. lit is shown that accident reconstruction at present does not provide the necessary information to relate the cause of accidents to the lack of road worthiness of vehicles. It follows that the vehicle behavior in proximity of its performance limit must be determined in order to infer its accident avoidance potential.
The paper presents a review of the state-of-the-art of vehicle modeling, simulation of vehicle maneuvers and full scale testing. The application of the direct method of the stability theory is suggested as a possible means of obtaining performance limit envelopes which are necessary for establishing standards of the performance of vehicles. 相似文献
The paper presents a review of the state-of-the-art of vehicle modeling, simulation of vehicle maneuvers and full scale testing. The application of the direct method of the stability theory is suggested as a possible means of obtaining performance limit envelopes which are necessary for establishing standards of the performance of vehicles. 相似文献
95.
李虎松 《西安交通大学学报(英文版)》1995,(2)
REGULATIONOFPRODUCTIONOFPARATHYROIDHORMONE-RELATEDPEPTIDE(PTHrP)ANDEXPRESSIONOFITSmRNAINAHUMANLIVER-DERIVEDCELLLINELiHusong;P... 相似文献
96.
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98.
Urban transportation is identified as a functional element in the broader context of urban facilities and services. From this point of view, the relative merits of separate information systems for transportation planning and general urban planning, as contrasted to unified systems for all urban management functions, are discussed. The overriding need to make the most effective use of urban resources argues strongly for the unification of urban information systems to the greatest possible extent consistent with the special data requirements of various functional programs. The need to identify and correlate data items for very small areal units and to keep current records of the constantly shifting patterns of social and economic activities in urban areas present difficult, but not insurmountable technical problems. However, the most serious barrier to the development and implementation of comprehensive urban information systems is concluded to be institutional, rather than technical, in nature. 相似文献
99.
A. H. Wickens 《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》1979,8(1):33-48
For railway vehicles having coned wheels mounted on solid axles there is, in general, a conflict between stability of lateral deviations from the motion along the track and ability to steer round curves. However, certain configurations of three-axle vehicle can satisfy the requirement of perfect curving and for certain values of the system parameters are dynamically stable. In the case where three wheelsets have semi-rigid articulation and either the distribution of conicity amongst the wheelsets or the position of the articulation joint are varied, it is shown that both flutter and divergence instabilities can occur at low speeds, in contrast to the more common dynamic instabilities of other forms of railway vehicle which are driven by the inertia forces. 相似文献
100.