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291.
Dietrich R. Bergmann 《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》1973,2(3):139-154
Vehicle dwell times are perhaps the most unpredictable parameters of station operations because of occasional passenger intervention. This paper reports on an investigation involving theoretical and Monte Carlo techniques to ascertain the sensitivity of station throughput to randomness in dwell times. Alternative configurations of vehicle loading positions, e.g., loading positions in parallel, in series, or in a series-parallel combination, are considered in an effort to rank the configurations by their associated performance levels. 相似文献
292.
293.
B. R. Davis A. G. Thompson 《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》1988,17(6):357-366
This paper considers the application of linear optimal control to the design of an active automobile suspension system. By inclusion of an integral constraint in the performance index it is possible to achieve zero steady state axle to body response to both static body forces and ramp road inputs. Full state feedback is achieved by reconstructing the state variables from easily measured quantities. 相似文献
294.
Static and changing port economic impacts 总被引:1,自引:0,他引:1
This paper attempts to provide general guidelines for conducting a port' economic impact analysis. In so doing, a methodology is proposed to organize efficiency the search for port-related industries and to determine the degree of their dependence on a port. this methodology is applied to the port of Hampton Roads. In addition, some constraints in predicting the changes in the economic impact of a port attribute to changes in the volume cargo are identified. 相似文献
295.
Contained herein are the results of research which quantifies the effects that various existing and projected truck configurations have as live loadings upon bridges which currently exist on the National Bridge Inventory (NBI). The truck configurations were determined from those actual or proposed vehicles which exhibit the highest GVW and which either are causing or are perceived to cause the highest levels of overstress on bridge superstructure elements. In order to simulate most accurately the actual field conditions, a criterion was defined which contained three major requirements: 1) The bridges utilized within the study shall be defined as being a statistically significant sample and be actual bridges taken from the NBI; 2) The analysis method shall be consistent with those actually used by engineers in designing and rating bridges, and; 3) The criteria utilized in evaluating the various bridge structures under the defined loadings shall be consistent with current practices. The results obtained indicates the acceptability of various truck configurations by GVW, size, and axle deployments, by system for the different criteria now in use. 相似文献
296.
This paper describes the theory, development and estimation of a simultaneous disaggregate model of automobile ownership and mode to work choices. The motivation for such a model and the general theory of the simultaneous probabilistic choice model are briefly discussed. The general model specification and the set of choices assumed to be available to each household is then considered. Finally, the variables used in the model are defined and the estimation results are presented. 相似文献
297.
298.
R. L. Cosgriff H. H. Yeh 《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》1975,4(4):249-271
The dynamic shuttle system treated in this paper consists of main line trains traveling at a fixed speed. Passengers are shuttled to and from these fixed speed trains by means of shuttle cars. The shuttle cars can provide local service and thus alleviating the need for stations along the route of the main line trains. The main line trains have a peak volume, depending upon operating speed which is an order of magnitude greater than existing modes. They provide high speed service to travelers in the belt traversed by the trains. 相似文献
299.
S. R. C. Wanhill 《Maritime Policy and Management》1974,2(1):48-55
The correct number of berths that a port should provide is solved by a model which minimizes the total port usage cost in terms of the costs of berth provision and the costs accruing to ships from time spent in the port. This model is then applied to Mina Zayed in the Arabian Gulf as an aid to future planning, and from different sets of cargo forecasts an optimal stategy is derived using a game-theoretic approach. 相似文献
300.