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751.
This article deals with the simulation of a vehicle/pilot system experiencing external disturbances. In the simulation, the car is modeled with two degrees of freedom and the pilot is assumed to respond to the state vector with a time delay. When perturbations are introduced, the pilot is expected to drive his car back to the initial state while minimizing a quadratic cost function. With some simplifications for low frequencies responses, the model is then used to simulate the response of different vehicles to an initial step in lateral displacement. The results from the simulations are interpreted in the light of the controllability diagrams.  相似文献   
752.
Part I of this paper has argued that any meaningful evaluation of transport system safety must include a consideration of the exposure to accidents, and has demonstrated the use and limitations of several measures of exposure at intersections and along links of the network. To complement this treatment of site exposure, this part of the paper will describe the use of group exposure measures in the assessment of risks incurred by people within particular population groupings. The use of induced exposure measures is also briefly reviewed.  相似文献   
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Using methods established in earlier work, calculations are carried out to reveal the influence of actuator bandwidth on the performance capabilities of a class of active suspension system for automobiles. The suspension consists of an actuator in series with a spring, the combination being in parallel with a passive damper, and the system is modelled as a single wheel station traversing a random road. The results indicate that a system with a 3 Hz bandwidth actuator and variable damping will have excellent ride performance qualities over a wide range of road roughness conditions. Since such a system can be expected to be easily adaptable to the running conditions, to provide good static and dynamic attitude control, to be capable of contributing to good steering control responses and to be inexpensive in terms of capital and energy consumption costs compared with most of the active systems which have previously been discussed, it is suggested that it is a prime candidate for further study and practical development.  相似文献   
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The idea of a passive safety belt operated solely by the motor car's door has been rigorously analysed on a mathematical model. By calculation methods, an optimal configuration of the device was produced and a working model built, based on the analytically obtained design specifications. The model proved the feasibility and advantages of the proposed system, which is based on the conventional 3-point safety-belt design and utilises existing car structures.  相似文献   
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Haritos  Z.  Elliott  A. 《Transportation》1983,12(1):3-20
Transportation - In Canada, transportation regulation has evolved in response to the country's unique economic and demographic conditions—a land mass larger than that of the U.S.A. with...  相似文献   
760.
This paper examines the growth of world trade in the period 1960-70 and its characterization by two indices, the Maritime Potential Index and the Maritime Dependence Index.  相似文献   
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