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821.
822.
This paper presents a new cost allocation method developed for estimating the fully-allocated costs of the excess peak hour bus transit service provided by two public transit systems. The estimates were produced for the explicit purpose of carrying out a realistic comparison of these costs and the costs of the potential provision of the same service by private operators. The method utilizes the same service data for the analysis. The pragmatic estimation of the fully allocated costs of service by the public and private sectors enables a more accurate estimation of potential cost savings. Sensitivity analysis was also performed using the same costing procedure to determine the range of cost savings that are feasible in a competitive contract arrangement of private sector providers. The new method separates costs of the direct provision of service from other indirect costs and thus facilitates the identification of each cost item and its significance in comparative cost estimates. 相似文献
823.
R. W. Vickerman 《Transportation Research Part B: Methodological》1985,19(6):471-479
Trip generation models have generally received less attention than other aspects of travel decision making. This article presents some explorations into the structure of trip decisions for shopping, using data from weekly shopping diaries. The paper compares alternative formulations of the naturally-ordered choice model used by Sheffi (1979) to avoid the problems inherent in multinomial logit models. Firstly, imposing cross-alternative restrictions on some of the coefficient values is termed the constrained model. Secondly, when no such restrictions are imposed, the model decomposes into a sequence of binary models, and this is termed the unconstrained model, which can be used to test the validity of the restrictions. The variables used include both shopping expenditures and locational factors, both of which are found to play a key role in shopping travel decisions, as well as more conventional socio-economic variables. A clearer understanding of the role of car ownership in travel decisions is obtained. 相似文献
824.
R. O. Goss 《Maritime Policy and Management》1990,17(3):221-234
This paper contrasts the economic policies adopted towards seaports by different countries in terms of their approaches to national, regional or local control. Various examples are presented and described, together with some of the difficulties that have been encountered. Examples are cited where national, regional and local governments have become involved, even though constitutional provisions appeared to present this. It is argued that national, regional and local governments all have interests in the efficiency of ports from various points of view; hence all should be involved. The arguments for and difficulties experienced in centralized planning and co-ordination are also discussed.
The variety of activities directly undertaken by port authorities is discussed, with the extreme positions labelled 'landlord' and 'comprehensive'. The remarkable variety of intermediate positions is also described. Whilst oversimplification is dangerous, the opportunities for expanding the private sector are analysed, even to the extent of wondering whether public sector port authorities are needed at all. This, therefore is the subject of the next paper. 相似文献
The variety of activities directly undertaken by port authorities is discussed, with the extreme positions labelled 'landlord' and 'comprehensive'. The remarkable variety of intermediate positions is also described. Whilst oversimplification is dangerous, the opportunities for expanding the private sector are analysed, even to the extent of wondering whether public sector port authorities are needed at all. This, therefore is the subject of the next paper. 相似文献
825.
826.
As urban systems increase in size and diversity, the factors which influence spatial change increase in number and their interactions become more complex. Increasing emphasis is thus being placed by some governments and agencies on regular reviews of policies and programs, to ensure that they are consistent with and facilitate the evolving urban form. Consequently, the monitoring of urban transport and activity systems is of increasing importance, to aid the review processes. This paper considers the progress which has been made in and use of procedures for monitoring urban, transport-related spatial changes. The specification, estimation and presentation of appropriate indicators is briefly discussed. Experience with the use of spatial monitoring procedures on data for two Australian cities has revealed several possible implications for transport investment practice and the development of monitoring and modelling procedures. These are discussed and the paper then indicates the approach which is currently being taken at ARRB towards developing a monitoring system. 相似文献
827.
With the port industry facing increased cargo volumes, the need for expansion of landside facilities is eminent. The ports face a dilemma which can cause considerable damage to their futures. This threat comes in the form of environmental policy. Since the early 1970's, Europe has been involved in an 'environmental crusade' which seeks to protect habitats and species of wildlife. The creation of 'environmental zones' to protect these areas, are spreading rapidly along the coastlines and waterways where ports are situated and in need of development to handle increased cargo volumes. This paper is aimed at developing an understanding of the potential impact of environmental zoning on the future of ports, as well as presenting the facts and legislation supporting this environmental crusade. 相似文献
828.
Earlier work by the Transport Studies Group of the Polytechnic of Central London on minibus development in Britain for the Transport and Road Research Laboratory provided a financial analysis of intensive urban minibus operation. This is taken as the basis for the application of cost-benefit analysis. Unit operating cost savings and passenger benefits are taken into account, using typical demand elasticities derived from earlier work. Particular attention is paid to the problem of evaluating passenger benefits for which waiting time at the roadside is not necessarily an adequate proxy. A direct survey of passenger waiting times indicates that these do not necessarily decrease when a higher-frequency minibus service replaces a conventional bus service but the improved convenience produces an increase in ridership which may be assessed in terms of a demand curve shift to estimate benefits obtained. 相似文献
829.
R. Morris 《Maritime Policy and Management》1983,10(1):53-60
In this paper, the author focuses attentioon on the so-called Melbourne Dockers War of 1971-3. Having descrided its mains events, he goes on to analyse of the unprecedented level of violence in the milieuof trade union elections. He traces this in part to the influx of criminal elements into the Federated Ship-Painters and Dockers Union of Australia (FSPDU) during the Second World War, and to the more immediate disagreement between rival factors concerning the direction which union activities, legal or othewise, should follow. He then assesses the implications of the episode for Australian politics, law and public administration in general. 相似文献
830.
Rajendra G. Kulkarni Roger R. Stough Kingsley E. Haynes 《Transportation Research Part C: Emerging Technologies》1996,4(6):407-424
This paper models traffic congestion formation on highways and roads by recognizing the centrality of dynamical systems and using concepts from complexity theory as imbedded in the spin glasses analogue. Further, it explores the concept of how an increase in air pollution caused by vehicle exhaust emission can be traced to traffic congestion, specifically to the acceleration/deceleration of vehicles on the roads. First, spin glass is introduced and then by applying the two-dimensional x − y Ising model and defining a Hamiltonian (based on Edwards-Anderson and Mattis models of spin glass systems) for a system of vehicles on the road, derivations are made of the specific friction of congestion and the bulk modulus of congestion using the Gibbs-Boltzmann statistic. Similarly using the interactions of vehicles with each other and the resulting accelerations and decelerations of vehicles as the basis for exhaust emissions, derivations are made of a specificity of exhaust emissions. These are analogues to the entropy models of thermodynamics. This series of derivations serves as an analytical model for detecting incidents of congestion and increase in air pollution due to exhaust emissions in transportation systems. 相似文献