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991.
Welfare effects of congestion pricing in Singapore 总被引:1,自引:0,他引:1
Paul W. Wilson 《Transportation》1988,15(3):191-210
This paper examines the Singapore Area License Scheme. Changes in scheduling and choices of transportation mode by commuters are discussed. Although the toll is shown to reduce travel times for many commuters, many commuters are shown to incur scheduling costs as a result of the toll. Using estimated parameters of an indirect utility function, welfare functions are computed to compare welfare levels prior to, and just after, the toll was put into place. The evidence suggests that the toll may have reduced welfare. 相似文献
992.
W.X. Wu B.V. Brickle J.H. Smith R.K. Luo 《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》1998,30(3):229-236
A model for the numerical simulation of vehicle/track interaction and stick-slip vibration is presented. A finite element model is developed to calculate vertical contact forces. These forces are then coupled through the contact patch into a non-linear time-domain model by which the stick-slip vibration behaviour of a wheel-rail system is analysed. The investigation suggests that stick-slip vibration may occur if a vehicle which has a maligned or an initial 'wind-up' wheeiset meets a vertical irregularity or contaminants on the track. 相似文献
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995.
Hamid Bazargan Hamid Bahai Amin Aminzadeh–Gohari 《Journal of Marine Science and Technology》2007,12(1):34-42
This study presents a new method for calculating return values. The essence of the method is that it utilizes nonstationary
data to calculate the return value for a region in the Northeast Pacific. The nonstationary data was obtained from a model
which was previously developed for the behavior of the significant wave height as a function of time in the region. The method
is illustrated by convolving two generalized Pareto distribution functions fitted to two parts of the model, computing a suitable
extreme value from the new distribution function, and calculating the return value using this extreme value. 相似文献
996.
A new marine propulsion system 总被引:1,自引:0,他引:1
HANWei-shi LIUTao 《船舶与海洋工程学报》2003,2(1):30-34
A new marine propulsion system is proposed . A small liquid sodium cooled reactor acts as prime mover; alkali-metal thermal-to-electric conversion (AMTEC) cells are employed to convert the heat energy to electricity; superconducting magneto-hydrodynamic thruster combined with spray-water thruster works as propulsion. The configuration and characteristics of this system are described. Such a nuclear-powered propulsion system is not only free of noise, but also has high reliability and efficiency. It would be a preferable propulsion system for ships in the future。 相似文献
997.
一种用于地铁轻轨的智能行车控制方法 总被引:5,自引:2,他引:3
本文利用模糊建模技术,通过建立调度员决策模型和引入新的思维,设计了高效的市郊铁路行车控制器。此项研究的主要目标是消除基本时刻表偏差及由车站或列车停发进路问题所引起的对列车运行的干扰。本文所提出的方法接近调度员的思维方式,在相关市郊铁路和地铁系统中具有应用价值。 相似文献
998.
B.Volf 《变流技术与电力牵引》2003,(6):20-22
论述了弹簧减振装置基本参数对改善机车车辆运行特性的转向架动态特性的影响.转向架动态特性主要影响机车车辆的总特性.车辆总特性又影响到车辆运行噪声的水平,同时对铁路线路产生不利的影响. 相似文献
999.
Stanislaw Raczynski 《Journal of Marine Science and Technology》2007,12(1):15-21
A commonly used mathematical tool in vehicle dynamics simulation is the ordinary differential equation. However, in some situations,
these equations may not be sufficient to solve problems. For robust flight, surface ship or submarine control design, safety
assessment, missile and aircraft guidance, the influence of disturbances, and differential games of pursuit–evasion, more
versatile tools are needed. The differential inclusion (DI) is a generalization of a differential equation that can be extremely
useful. The solution of a DI is not just a model trajectory or a set of trajectories obtained by a randomization of the original
problem. The solution is a reachable set, and it is a deterministic object. A differential inclusion solver and its application
to vessel movement are described. Compared to previous publications on the DI solver, the new feature is an implementation
of the fuzzy sets technique to improve the resulting images. It is pointed out that the reachable sets cannot be assessed
properly while treating the uncertain variables as random. The application of the DI solver can give a proper view of the
regions in the state space where all the possible model trajectories belong. 相似文献
1000.