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991.
This paper examines the claim that US bus transit productivity has declined in recent years. It does so with reference to a piecewise-linear best-practice (DEA) production frontier, computed for multi-modal bus transit between 1988 and 1992. Efficiency is measured both by a Russell (static) and Malmquist (dynamic) measure of productivity change. The principal finding is that, overall, bus transit efficiency has improved slightly over the period.  相似文献   
992.
Inspite of the inherent weaknesses in aggregate demand models, they continue to be used in everyday applications, especially in developing countries. The largely data intensive disaggregate model preclude its application in many cases. This paper attempts the formulation and calibration of an aggregate total demand model for estimating inter-district passenger travel by public transport in Sri Lanka. In its process, an investigation is made of the common problems in the aggregate approach while examining possible remedial measures to improve the accuracy and (hence) the usability of the aggregate model. It is argued that commonly used variables and functional forms are inappropriate for making accurate estimates in developing countries. Consequently, the model calibration is shown to incorporate variables representing urbanisation, under-development, transfers, a mode-abstract cost function and intrinsic features. The necessity for functional form for each variable to be based on behavioral assumptions that are tested using the Box-Cox transformation for ensuring the best fit of the data is also observed. Although, the model form was calibrated for Sri Lanka, the model is generalised in order for its applications to other countries as well as, both, inter-district and intercity travel demand estimation.  相似文献   
993.
There is a renewed interest in intercity and long-distance rail services in many countries, with both new high-speed rail services and improvements to conventional rail under review. The current study reports on an investigation using a stated choice experiment, of the demand for sleeper services between Sydney, Northern New South Wales (NSW) and Brisbane in Australia, a 12 to 14 hour trip, just after a decision by the NSW government to temporarily suspend sleeper services and introduce seating service only, pending an inquiry into the demand for such loss-making services under alternative price and service levels. A matrix of direct fare elasticities within the rail mode and between rail and competing modes are obtained for concession and non-concession travellers from a nested logit model. The empirical evidence extends our knowledge of the sensitivity of the long distance passenger market to a range of rails fares, distinguishing between classes of fares and levels of service.  相似文献   
994.
Lowering the speed of car drivers will have positive impacts on environmental pollution and the number of road accidents. It is therefore a potentially interesting policy option for governments which want to reduce negative externalities of transport. In this paper, the acceptance of such policies is analysed by means of a survey questionnaire among car drivers and public transport users. First, an analysis is presented on the general speed behaviour, the behaviour on distinct road types, the acceptance of lower limits, and the acceptance and perception of electronic speed limiters. Next, a statistical analysis of subgroups is carried out. It is concluded that the speed of car drivers is, in general, not considered to be a main problematic issue by drivers and non-drivers; therefore, there is little scope for the acceptance of changes in speed policies. When speed policies are changed (lower limits), it seems to be most effective to emphasize safety aspects in order to increase the support of the public. However, psychological factors of speed behaviour may play an important role in this respect.  相似文献   
995.
The objective of this paper is to introduce a computer simulation model with on-screen animation graphics, which can simulate the operations of a container terminal equipped with straddle carriers. The movements of the equipment are simulated as realistically as possible, to include time losses due to the mismatch in the sequence of equipment movements and to traffic congestion. Trucks are normally served in a specified area, but in some cases, straddle carrier drivers can call the truck to be served directly in the container storage areas. The experience of operators is incorporated in the model, in the form of a knowledge base, that is used to simulate the above process and determine the service discipline. The model was designed to evaluate different configurations (changes in yard layout, equipment number and productivity, truck arrival pattern and service discipline) of the simulated system. The proposed model was used to examine the differences between “the observed” operations strategy and the strategy dictated by the operational rules of the port of Piraeus. The results indicate that “the observed” strategy leads to shorter truck service time but increase the traffic conflicts in the terminal's internal transport networks.  相似文献   
996.
Delays caused by congestion at the US/Canadian border crossing between Washington state and British Columbia have underscored the need for some sort of intervention. One obvious congestion-mitigation measure would be to estimate delay times and then relay this information to motorists so that they could select among alternative border crossing sites, or delay their trips. This paper applies duration models to estimate vehicular delay and demonstrates the usefulness of such models as a basis for a fully automated motorist information system. The paper also explores the flexibility of duration models, in providing estimates of vehicle delay, by using alternate parametric forms and assessing prediction accuracy.  相似文献   
997.
Stated preference (SP) rating experiments are easy to design and conduct. Furthermore, they constitute a generalisation of SP choice experiments in terms of the information about preferences that can be achieved. However, its results are sensitive to the numerical values assigned by the analyst to the semantic scale used by individuals to express their preferences. We consider this problem in depth using a variety of statistical techniques, including ordinal probit and a novel optimal scale linear regression approach.  相似文献   
998.
Editorial     
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999.
The established ownership mix of urban bus operations in Australia provides a unique opportunity to investigate the productivity differences between public and private bus service supply. Using duality theory in economics which links economic indices of factor productivity to the cost structure of a firm, we develop empirical measures of total and partial productivity of inputs, and adjust the differences for the effects of ownership status and operating environment. The evidence supports the notion that private supply of public passenger transport in general has performed more efficiently in the past than public supply, although the differences in productivity need not continue in the future.  相似文献   
1000.
Historically, computer models have grown in complexity, and consequently have become more difficult to use. At the same time there is a growing need for quick-response methods and techniques for broad-brush policy formulation and decision making. The personal computer and its attendant software offer new means for quantitative sketch planning. This paper illustrates two PC-based applications for quick-response exercises. These involve interactive mapping and data analysis methods for the appraisal and interpretation of transport data, and the development and use of eclectic models for systems analysis and scenario generation. The LAMM and DIAMONDS packages are described, and their use in data analysis is illustrated. The Trends Integrator Procedure (TIP) is used to formulate a simple but versatile model for investigation of developments in an urban retailing system. These packages all run on PC's and offer powerful and adaptive tools for improved transport planning.Nomenclature a i a technical coefficient indicating the influence of the unique factor component (U i ) for factor F i - c ij a technical coefficient relating the influence of factor F i on factor F j - F i the relative change in the level of factor F i - U i the relative change in the unique factor component for F i   相似文献   
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