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141.
142.
James R. Jones Lu Qu Kenneth L. Casavant Won W. Koo 《Maritime Policy and Management》1995,22(1):63-80
A mathematical spatial programming model developed to analyse changes in international and hinterland commodity flows through a regional port system is applied to wheat shipments through the U.S. Pacific Northwest port system. Two scenarios, one focusing on a Chinese quarantine on wheat shipments from the Pacific Northwest and the other on possible closure of barge transportation on the Columbia-Snake River, illustrate the capacity of the model to evaluate the impacts of international and hinterland shocks on the regional port system. 相似文献
143.
Mary R. Brooks 《Maritime Policy and Management》1983,10(2):77-85
This paper focuses on the potential effects the UNCTAD Liner Code of Conduct's provisions for cargo reservation on consumers of shipping services, with special reference to Canada. It is clear that as more nations enact flag-discriminating legislation then fewer choices amongest distribution options will exist for the consumer. This will involve nations like Canada in a fundamental reassessment of their current shipping policy, since the rationale of 'free market' competition will no longer be valid: carrier and services options will be curtailed. In the light of this, Canada will be forced to examine the concepts of 'free trade' and 'private sector enterptise' and develope a considered response that protects the consumer interest. 相似文献
144.
Although recent budgetary considerations by the Federal govenment do not portend well for urban public transit, some transit systems are considering expansion into less densely-settled areas further from the Central Business District. Of some concern to planners has been their belief that suburban and rural dwellers may be much less inclined than urban dwellers to support expansion of transit service. This paper presents an analysis of a random-digit dialing/mail-out, mail-back survey conducted in Washtenaw County, Michigan which was designed specifically to examine differences in attitudes between urban and rural residents. Six mutually-exclusive spatial strata were established based upon population density. This paper tests for expected spatial differences in socioeconomic and demographic variables and then examines spatial variations in attitudes toward public transportation. The major conclusion is that the expected spatial variations in attitudes about transit service provision between the spatial strata do not arise. Most of the significant differences found are with respect to questions which relate to where transit is provided. Residents in rural (urban) areas support more strongly the provision of services to rural (urban) areas. Many residents, however, will support transit service that may not benefit them directly. 相似文献
145.
R. Caillol 《Maritime Policy and Management》1981,8(1):41-47
With the soaring fuel costs modifying the general cost structure of ship management. shipowners running deep-sea services are being forced to reconsider the routeing of their vessels. some geographical regions (and ports within those regions) appear to begaining new spatial advantages in overall cargo flows because of this factor. This study looks at a methodological framework for a computer simulation analysis of these advantages by treating a specific example: that of second- and third-generation container vessels plying between the Far East and Europe. It tests the hypothesis that, on this particular route, the increase in fuel costs is tending to give a competitive edge to Mediterranean ports compared with those in north-western Europe. 相似文献
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147.
R. M. Goodall W. Kortü m 《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》1983,12(4):225-257
Active control systems offer significant functional advantages over passive systems; their introduction into production-line vehicles, however, is cautious and slow. This survey describes the recent progress in the analysis, design and technology of active controls in vehicles. It includes the state-of-the-art of their introduction into operation as well as their future potential in view of recent advances in technology and computer aided design strategies. The survey has been limited to suspensions for vehicles on roads and tracks. 相似文献
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Non-Contact Suspension and Propulsion Technology 总被引:3,自引:0,他引:3
H. Alscher M. Iguchi A. R. Eastham I. Boldea 《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》1983,12(4):259-289
As a result of extensive research and development in several countries, the technologies of magnetic suspension and linear electric drives are becoming available for transportation applications. The successful demonstration and operation of prototype vehicles has established the technical viability of these systems. Several urban transit or shuttle services, with magnetic suspension and/or linear motor propulsion are likely to be operational within 3-4 years. After the final stages ofdevelopment and rigorous testing, high speed systems are likely to be an option for intercity implementation by the end of the decade. This paper presents a report on the worldwide status of R&D and test programs of non-contact suspension and propulsion technology for guided ground transport. 相似文献