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441.
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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This study was designed to examine the relationship between actual and perceived values of cost and time for the work trip and to examine how perceptions have changed over a period of dramatically increased travel costs. Variations in the relationship between perceived and actual values were examined as a function of situational and attitudinal variables. Two telephone surveys were conducted one year apart (Fall 1978 and Fall 1979). On the next working day following a survey, a research assistant recreated the respondent's work trip, recorded time values and used distance measures, car type information and parking costs to compute travel cost. The first survey revealed that most auto users were unable to articulate dollars-and-cents driving costs for the work trip, but auto users in the second survey were able to provide fairly accurate cost estimates. Dramatic changes in fuel prices between surveys is probably the main reason for the change in driving cost awareness. Auto users were also asked to rate relative costs of driving a car compared to using the bus for the work trip. These ratings showed that auto users tended to underestimate driving costs relative to bus costs, but this tendency decreased from the first to the second time period. Commuters in all modal groups at both time periods tended to overestimate travel times. Perception of travel time varied as a function of mode, perceived comfort (for car users), and perceived convenience and number of transfers (for bus users).To whom correspondence should be addressed.  相似文献   
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The choice of fare policy is more flexible in personal rapid transit than in conventional transit and has some unique aspects. The implementation of fare policies as a function of distance are discussed, and, following a discussion of how the fare would be collected in a PRT system, consideration is given to whether the fare should be per person or per vehicle.  相似文献   
448.
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   
449.
Although liner conferences are traditionally assumed to possess effective monopoly power, such a view ignores many important aspects of their competitive environment. This article examines some of these neglected competitive features and shows how they may decisively influence conference pricing strategies.

In the analysis of linear shipping, the notion that conferences are effective monopolists lies at the root of many of the grievances of the conference system. It has also become an integral part of the conventional wisdom of shipping economies, to such an extent that the monopoly power of conferences is virtually regarded as a matter of established fact rather than what it really is-namely a postulated assumption open to testing and refutation.

It is the purpose of this paper to explore the competitive conditions of the industry in which liner conferences operate and to try and establish the extent and limitations of their market power. This will involve an analysis of hte bariers to entry which conferences may be protected by, the manner in which the relevant industry should be defined, the possibility and consequences of new entry, and the response of conferences to their competitive environment.  相似文献   
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