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631.
632.
Doubting that its infant shipping industry would be able to overcome, unaided, the bottleneck it was becoming for the country's export expansion policy, the government of the Republic of China has implemented in the last 25 years a set of shipping policies to address the problem. This paper examines the details of these policies, assesses the extent to which they have succeeded, and comments on the conflicts their implementation has created within the shipping and shipbuilding sectors. 相似文献
633.
A. G. Thompson B. R. Davis 《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》1988,17(4):179-192
In optimally controlled active suspensions with either full or incomplete state feedback there is tradeoff between system performance and overall stiffness. It is sought to remove this limitation by incorporating integral action which results in a system with infinite stiffness towards static loading, but which is soft with respect to road inputs. The system is also able to eliminate the steady state deflections due to step and (potentially) ramp type inputs at the wheel. Optimality is retained at the cost only of a derivative constraint and the system can be physically realised using output feedback control. 相似文献
634.
Using case study material, this paper examines the relative merit of metros and high performance bus systems in use in Third World cities. It demonstrates that buses with suitable priority measures are capable of meeting high passenger demands. The paper also shows that despite the poor financial performance and other shortcomings of metros, they can yield a respectable economic return. The paper draws on studies undertaken as part of the research program of the Overseas Unit of the Transport Research Laboratory. 相似文献
635.
R. Van Der Valk H.B. Pacejka 《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》1993,22(2):97-121
A dynamical model is presented to analyse the stability of motion of the two-wheeled 'Fokker F.28-like' landing gear including tyres. The model is equally applicable to similar landing gears. The influence of the introduction of a specially designed torsional damper on the dynamical behaviour of the landing gear-tyre combination is investigated. Results of the stability calculations are supported by test results. 相似文献
636.
Estimates of the numbers of trips likely to be made by individuals and of the modes of transport that will be available to them for those trips are provided by the trip production model. The objective of the work described in this paper was to investigate the geographical stability of the trip production model by comparing the numbers of trips estimated by the model when using national rather than local data. The 1972/3 National Travel Survey was used as the national data. Household interview survey data from the transportation studies of Lincoln, Sheffield/Rotherham, South East Dorset and Bristol were the local data sources. Three home based trip purposes are modelled; 24 hour work, 24 hour shop, 24 hour other.The models calibrated from national and local data perform similarly provided both operate with local trip rates. The car ownership sub-model with national parameters produces similar forecasts to the models with local parameters. There are probably real differences in household trip rates for some trip purposes between urban areas. 相似文献
637.
F. Donati R. Genesio A. Laurentini V. Mauro G. Menga M. Milanese 《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》1974,3(3):141-161
The purpose of this paper is to present analytical techniques for evaluating the dynamic riding behaviour of a vehicle. These techniques have been applied to a fairly sophisticated model of a bus, where a three-dimensional structure, elastic frame and non-linear shock-absorbers have been considered.
A computer simulation program (DYNASIM 3) has been set up, which is actually used at FIAT corporation for evaluating vehicle riding qualities and improving the design process. 相似文献
A computer simulation program (DYNASIM 3) has been set up, which is actually used at FIAT corporation for evaluating vehicle riding qualities and improving the design process. 相似文献
638.
Mary R. Brooks 《Maritime Policy and Management》2013,40(3):187-189
Part 2 of this paper deals with the variety of ro-ro cargo-handling methods employed in Marseilles, and considers the hinterlands and land transport links with the ro-ro services of the port 相似文献
639.
Paul R. Tétreault Ahmed M. El-Geneidy 《Transportation Research Part A: Policy and Practice》2010,44(6):390-402
In recent years, several transit agencies have been trying to be more competitive with the automobile to attract choice riders. Transit agencies can only be competitive if they can provide services that are reliable, have a short access and egress time, and have run times that are comparable to automobiles. Several transit agencies try to be competitive through offering faster service, such as limited-stop (express) bus service. This study uses AVL and APC data, in addition to a disaggregate data obtained from a travel behavior survey, to select stops and estimate run times for a new limited-stop service that will run parallel to a heavily used bus route (67 Saint-Michel) in Montréal, Canada. Three different scenarios are developed based on theory and practice to select stops to be incorporated in the new limited service. The time savings for each scenario are then evaluated as a range and a fourth scenario is developed. A limited-stop service is recommended based on selecting stops serving both directions of the route, major activity points and stop spacing. This study shows that implementing a limited-stop service would yield substantial time savings for both, the new limited service and the existing regular service running in parallel. 相似文献
640.