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1.
Abstract

Flexible transport services (FTS) have been of increasing interest in developing countries as a bridge between the use of personal car travel and fixed route transit services. This paper reports on findings from a recent study in Queensland Australia, which identified lessons from an international review and implications for Australia. Potential strategic directions, including a vision, mission, key result areas, strategies, and identified means of measuring performance are described. Evaluation criteria for assessing flexible transport proposals were developed, and approaches to identifying and assessing needs and demands outlined. The use of emerging technologies is also a key element of successful flexible transport services.  相似文献   

2.
Intermodal freight transport has developed into a significant sector of the transport industry in its own right. This development has been followed by an increase in intermodal freight transportation research. We contend that a new transportation research application field is emerging; and that, while still in a pre-paradigmatic phase, it is now time to move on to a more mature independent research field. An independent research field can be justified because intermodal transport is a complex system that has characteristics which distinguishes it from other transport systems. We have reviewed 92 publications in order to identify the characteristics of the intermodal research community and scientific knowledge base. This paper will discuss aspects of this research, assessing the status quo and seeking directions for the future. To conclude, we will propose an intermodal research agenda which can direct the intermodal research field towards a period of “normal science”.  相似文献   

3.
Over recent decades, there have been numerous cases of land-based transport policies that have lacked clear and coherent strategies. This has not only hampered the resolution of issues like road congestion, but has also created new ones (e.g. strong social opposition to new train infrastructures). The absence of such strategies highlights the need for long-term transport policies with a wider vision of the issues, since land-based transport cannot be considered from just a technical perspective.The main objective of this article is to implement a participatory integrated approach to facilitate the understanding of land-based passenger transport governance issues on Tenerife, in the Canary Islands. Relevant policy issues and alternatives are identified by the stakeholders involved. The inclusion of stakeholders in the assessment process is crucial to frame transport governance issues appropriately and to define and assess plausible policy alternatives. This assessment process even included a final step of validation of the results by stakeholders to foster discussion among them about transport issues and policy alternatives.Finally, due to the obstructive role played by some stakeholders in influencing past transport policies, an analysis of possible coalitions among stakeholders is also discussed.  相似文献   

4.
The interaction between accessibility and rural development is a subject of current concern. The degree of accessibility determines the ability of individuals to participate in development and other social activities. The paper describes the development of a numerical method for quantifying accessibility-benefits suitable for application in developing countries. The methodology provides an integrated approach to analysing accessibility by considering all constraints faced by individuals, particularly their income. The method can be used to evaluate different accessibility-enhancing strategies, and to quantify the benefits derived by different groups of individuals under various states of socio-economic development in rural areas of developing countries. The application of the accessibility-benefits model is demonstrated using two hypothetical case studies featuring the effects of improving intermediate means of transport and improving temporal strategies. The purpose of the case studies is to demonstrate how different accessibility-enhancing strategies can be related to the key model parameters, and to show the likely magnitude of the benefits, in monetary terms, that can be attained by individuals with different income levels.  相似文献   

5.
Transport planning is usually based on models’ forecasts, but the reliability of their outputs depends so much on the quality of input-data they are fed with. Discrete-choice models are used to characterise travellers’ behaviour in choosing their transport mode. Their calibration process is usually based on data stemming from household survey campaigns. However, the modelling in multimodal and intermodal transport on an interurban level is far more complicated and costly than in the case of an urban area. An alternative way to reduce costs is achieved by designing a choice-based sampling strategy where household surveys are replaced by specific surveys for each transport mode. This strategy generates a non-random sample that has to be treated correctly during the estimation process. In principle, the sample does not represent population market quotas for each different transport option. Moreover, as a result of both physical and functional constraints, the survey period cannot cover all origin–destination pairs (O–D pairs) in an optimal way and, consequently, the above-mentioned bias also affects each different individual O–D pair or, at least, group of pairs. In order to overcome this problem, this study presents a new procedure derived from the introduction of maximum likelihood estimators. These estimators assume the original mode options in terms of population quotas and in terms of O–D groups of pairs. The procedure is based on the optimisation of an objective-function to correct the above-mentioned bias in a way similar to the estimators of samples based on different choice options. The method named DWELT estimates the parameters corresponding to each explanatory variable using mode shares for each O–D pair or group of pairs. DWELT has been successfully validated in the case study of the Madrid–Barcelona interurban corridor in Spain. This result allows to achieve a more flexible cheaper survey procedure for interurban transport planning activities. Therefore transport policy strategies could be better designed and tested with lower costs.  相似文献   

6.
This paper presents and evaluates a new method for how emissions from freight transport routes with single or several points of loading and unloading, can be allocated to individual consignments. The method, called Dedicated Distance Proportional Allocation (DDPA), has been developed based on a literature review, discussions with logistics providers, and analysis. DDPA is designed to have low data processing requirements and be easy to explain to actors involved. Furthermore, it supports several levels of information availability, and accounts for any set of vehicle-limiting factors, as well as prepositioning/repositioning. DDPA has been evaluated in simulations with different levels of information availability, together with three existent allocation methods: the Equal profit method (EPM), the CEN EN16258:2011 standard and the Greenhouse gas (GHG) protocol. The simulations show that the GHG protocol under-allocates the total amount of emissions, on average. EPM and DDPA achieve equal relative savings, whereas for CEN EN16258:2011 and the GHG protocol, relative savings vary, on average. When DDPA is used with low level of information availability, an error is introduced which can be reduced by applying compensation factors. Since DDPA accepts low information availability, the Intelligent Products concept can be applied for computing and storing emissions allocations, at the time of unloading. The results from this study can be used for further development and implementation of consignment allocation methods. Furthermore, by combining DDPA with other environmental load approaches for other parts of a product’s life cycle, a complete life cycle assessment of the product’s environmental impact can be obtained.  相似文献   

7.
Among the crises facing our society is the public's loss of confidence in technical professionals and their ability to make decisions about large-scale projects (such as highways) in the public interest. To overcome this crisis of confidence, this paper hypothesizes a model for the role of the technical professional in the process of reaching decisions about public actions.In evaluating technological projects with social consequences, one key issue is the differential incidence of impacts. Typically, some groups are hurt in order that others may benefit. Social equity must be considered explicitly. Such presently-used techniques as benefit-cost analysis and point-rating schemes are unsatisfactory. New techniques are needed, reflecting a more comprehensive model for the role of the technical team in the political process.A normative model is outlined. First, the objective of the technical process is defined: to achieve substantial effective community agreement on a course of action which is feasible, equitable, and desirable. Second, a process for achieving this objective is proposed. A key element of this process is a four-phase strategy of technical and community interaction activities to achieve the objective. The basic premise of this approach is that the role of the technical team is to clarify the issues of choice, to assist the community in determining what is best for itself.This theoretical model has resulted in several practical products. A procedural guide for use by highway and transportation agencies has been prepared, and a number of specific operational techniques have been developed and are included in the guide. The procedural guide is now being field-tested in several state highway departments. The theoretical model has already been useful in identifying, in one highway department, opportunities for significant changes in the agency's mission, organization and procedures to enable it to be more responsive to public concerns. The theoretical model also has served as the basis for the development of federal guidelines for consideration of social, economic and environmental factors in highway planning and decision-making, in all of the state highway departments in the U.S.This is a revised version of a paper presented to the Seventeenth North American Meeting, Regional Science Association, November 6–8, 1970.  相似文献   

8.
In the next few years, exciting developments in the field of freight transport are likely to occur. The Channel Tunnel will be perceived as giving railways much greater distance of operation, compared to the current train ferry to/from Great Britain. The further development of swap-body technology will allow easier modal transfer and the creation, in 1992, of a single market in Europe will transform the pattern of trade. All of these are likely to have significant impacts on modal choice, and hence modal split, in freight transport. Reappraisal by many firms of the modes of transport used is likely but will it result in a net transfer of freight from road to rail and, if so, to what extent? To answer such questions, an accurate and reliable method of predicting modal split is required. Research in the past has concentrated on the development of modal split models based on generalised costs. These fail to explain adequately the prevalence of road freight in the UK. From surveys of freight managers within industry, it is clear that models to date rely too heavily on the economic cost factor and too little on behavioural factors (Jeffs 1985). This paper derives from a recent study of freight transport modal choice from the standpoint of the transport decision-maker within the firm. It attempts to shed light on the actual parameters which should be incorporated into a modal split model. Many variables appear to exert an influence on modal choice decision-making process. However, it is possible to categorise them into six main groups, namely: customer-requirements; product-characteristics; company structure/organisation; government interventions; available transport facilities; and perceptions of the decision-maker him/herself. It is the interactions and inter-relationships between these which ultimately determine freight modal split. This study has shown that the relationship between the outcome of the transport decision process and the values of particular determinants of modal split is not straight-forward, due to the complexity and variety of interactions involved. Perhaps one of the main reasons for researchers' failure hitherto to develop a successful modal-split model has been the preoccupation with techniques that rely on the development of common metric (e.g. generalised cost), which has led to the exclusion of some important explanatory variables along quite different dimensions. Another important issue concerns the appropriate level of aggregation. In order not to reduce the explanatory power of the key variables, it is important to work at a disaggregate level, although this does make substantial demands on data. The use of factor analysis enables both the aggregation of information without loss of behavioural reality and the specification of variables in terms of a common metric. In conclusion, freight transport has usually been examined within too narrow a framework. It must be placed firmly within the context of the total industrial process. The demand for freight transport is directly influenced by the level, composition and geographical distribution of production and consumption activities. Freight flows are complex and so it is highly unlikely that a universal mode-choice model can ever be developed. Future research should, therefore, be directed towards developing partial models in response to specific needs of those involved in decision-taking in the freight sector.  相似文献   

9.
Despite the growing development of tools that can integrate land use and transport, the desired integration is still illusive in daily practice. To address this gap, the current study uses spatial metrics, a set of methods traditionally used for studying changes in the spatial structure of landscapes, which are translated into the domain of transport planning. It examines how spatial metrics can be integrated into “Land Use Transport” strategy-making, and how useful they are according to the practitioners’ perceptions. A Light Rail Transit corridor in Granada (Spain) provides the empirical focus of this research. Land use characteristics such as: land use mixing, land use diversity and green areas connectivity were successfully studied using spatial metrics, and they were used to map three “Land Use Transport” strategies: (i) proximity dynamics and non-motorised modes; (ii) modal shift from cars to Light Rail Transit system; (iii) shared spaces between motorised and non-motorised modes. Practitioners perceived that spatial metrics could improve the “Land Use Transport” strategy-making process in comparison with traditional methods used in practice. However, certain shortcomings related to the usability of spatial metrics are also highlighted and discussed. This study concludes with a reflection on research challenges for adapting spatial metrics to transport practice.  相似文献   

10.
Transit Oriented Development (TOD) with railway service is recognized as a sustainable mode of development for highly dense megacities. In addition to providing safe and efficient transit services, reducing auto dependence and therefore less need for highway expansions, the improved accessibility of TOD influences commuters’ residential location choices and the resultant housing value. Traditionally, statistical approaches have been used to estimate the relationship between railway development and housing value for individual sites. To some degree, TOD has also been studied with integrated land-use transport models. While useful, they lack an analytical framework to study the region-wide impacts of TOD on residential location and travel choices and the resultant land value changes. In this study, the joint railway and housing development strategy is modeled based on a combined equilibrium formulation with the bid-rent process. The problem is formulated as a mathematical program with equilibrium constraints, in which the upper level optimizes the objective for the joint development strategy by deciding on the combination of housing supplies and railway service levels. Analytical results are obtained for a single corridor in a multi-modal transport network, which are further illustrated by sensitivity analyses. A numerical example is constructed to demonstrate the approach and compare with other separate development strategies. The results generally confirm the synergy between railway and housing developments.  相似文献   

11.
The scenario workshop is an example of the Scandinavian tradition of citizen involvement. The method is a mix of scenario and workshop. Scenarios produced by experts (scientists) are presented to a local community in a workshop lasting two to three days during which local participants produce criticism, debate and plans for community action. The method, originally used to actively involve citizens in the development of environmentally sustainable cities in Denmark, is now in use throughout Europe, as the various EU directorates have become very aware of their usefulness. A method has now been generated at the Copenhagen Business School for the field of transport. Four transport scenarios were generated relating to post-Fordist production systems, transport and the concept of sustainable mobility. They are to be presented in a transport-intensive region of Denmark to analyse barriers against environmentally induced adjustments to the transport sector and to find new solutions to the dilemma by creating dialogue between planners, politicians and transport managers.  相似文献   

12.
Mobility management (MM) is a transportation management policy that uses “soft” measures to attempt to reduce car use and promote sustainable transportation modes such as public transport, bicycles, and walking. Using communication and other means, MM induces voluntarily change towards more sustainable transportation modes. We implemented MM marketing to promote an experimental community bus service. This project had two components: a questionnaire conducted in the service area and a monthly newsletter. The questionnaire was more than a survey; it also communicated information about the bus and helped promote bus use. One month after the survey, we implemented a follow-up survey targeting the initial survey respondents. Results suggest that the MM program produced a general increase in bus use, as well as mouth-to-mouth advertising, that helped promote bus use.  相似文献   

13.
This paper deals with the development of a strategic approach for optimizing the operation of public transport system that considers both user's objective and operator's objective. Passengers of public transport are assumed to seek a minimum wait time to conduct the trips, while on the other hand, operators are concerned with the efficient operation such as minimum fleet size. The average minimum wait time is to be achieved by creating an optimal despatching policy for each vehicle from the terminal. As for efficient operation the utilisation of vehicle should be maximised by having a minimum number of vehicles in operation. User's and operator's objectives are optimized within certain operational constraints such as vehicle capacity to maintain acceptable level of service. The i‐model is contructed in a bi‐level programming form in which the user's objective is minimized by dynamic programming and the operator's objective is minimized by various routing strategies. Furthermore, an algorithm and a contrived example are developed to solve and see the performance of the approach.  相似文献   

14.
Travel planning by employers promoting more sustainable travel has delivered less car dependent behaviour for the commute in many places. Area-wide or precinct travel plans are less common but, where they exist, attempt to provide a more holistic approach through capturing synergies between employers and employees throughout a precinct. Area-based travel planning aimed at influencing employers, employees and residents are new, especially in relation to creating synergies for a single precinct that has more of an origin focus with participants travelling to diverse destinations. This paper examines various strategies that have been employed in order to achieve greener travel and to provide a self-sustaining travel planning environment. The aim of this paper is to assess the community awareness, interest and involvement with a number of green initiatives and to understand how sustainable travel planning has been absorbed by residents within a new regional centre in New South Wales, Australia. The analysis of a resident survey undertaken in 2011 distinguishes between the community awareness and their propensity to take part in each of the greener travel initiatives. The results show that a generic approach is likely to be less effective than segmenting the market so as to more directly target likely participants. Attitudes to greener travel are also highly significant and working to change them should also affect potential take up of sustainable travel initiatives. The conclusions inform the development of successful precinct based travel demand strategies both in Australia and beyond.  相似文献   

15.
The city of San Francisco is undertaking a large-scale controlled parking pricing experiment. San Francisco has adopted a performance goal of 60–80% occupancy for its metered parking. The goal represents an heuristic performance measure intended to reduce double parking and cruising for parking, and improve the driver experience; it follows a wave of academic and policy literature that calls for adjusting on-street parking prices to achieve similar occupancy targets. In this paper, we evaluate the relationship between occupancy rules and metrics of direct policy interest, such as the probability of finding a parking space and the amount of cruising. We show how cruising and arrival rates can be simulated or estimated from hourly occupancy data. Further, we evaluate the impacts of the first two years of the San Francisco program, and conclude that rate changes have helped achieve the City’s occupancy goal and reduced cruising by 50%.  相似文献   

16.
The paper describes an approach to the vexing problem of transport planning and policy. It deals jointly with three questions, which in today's practice are addressed separately: How are hypotheses about transport problems and alternatives to their solution developed? How can a good plan or policy be identified? What is the process of implementing a transport plan or policy? In doing this the paper has the ambitious objective of proposing a new model and process for transport planning and policy. It is applicable in developed and developing countries and is not restricted to the transport sector. The paper builds on, and is a reinterpretation of two cornerstone transport planning and decision-making models – the CATS (Chicago Area Transportation Study) Planning and Design Model and Braybrooke and Lindblom's Disjointed Incrementalism. It advances a technique of experiential incrementalism (termed polisanalysis) to develop and implement plans and policies. It proposes that problems should be diagnosed by observation and continuous data collection; that their continuous analysis, finding the “cure”, and implementation take place through the method of experiential incrementalism. In this method interventions are grounded on the theories of neoinstitutional economics and psychoanalysis and derived using contact function, explained in the paper, which renders the method scientific replicability. Experiential incrementalism can employ a wider array of options in planning and policy than is presently thought possible. Like other scientific methods, its application requires rigorous training.  相似文献   

17.
Transport systems in real cities are complex with many modes of transport sharing and competing for limited road space. This work intends to understand how space distributions for modes and interactions among modes affect network traffic performance. While the connection between performance of transport systems and general land allocation is the subject of extensive research, space allocation for interacting modes of transport is an open research question. Quantifying the impact of road space distribution on the performance of a congested multimodal transport system with a dynamic aggregated model remains a challenge. In this paper, a multimodal macroscopic fundamental diagram (MFD) is developed to represent the traffic dynamics of a multimodal transport system. Optimization is performed with the objective of minimizing the total passenger hours traveled (PHT) to serve the total demand by redistributing road space among modes. Pricing strategies are also investigated to provide a higher demand shift to more efficient modes. We find by an application to a bi-modal two-region city that (i) the proposed model captures the operational characteristics of each mode, and (ii) optimal dynamic space distribution strategies can be developed. In practice, the approach can serve as a physical dynamic model to inform space distribution strategies for policy makers with different goals of mobility.  相似文献   

18.
This paper investigates how California may reduce transportation greenhouse gas emissions 80% below 1990 levels by 2050 (i.e., 80in50). A Kaya framework that decomposes greenhouse gas emissions into the product of population, transport intensity, energy intensity, and carbon intensity is used to analyze emissions and mitigation options. Each transportation subsector, including light-duty, heavy-duty, aviation, rail, marine, agriculture, and off-road vehicles, is analyzed to identify specific mitigation options and understand its potential for reducing greenhouse gas emissions. Scenario analysis shows that, while California’s 2050 target is ambitious, it can be achieved in transport if a concerted effort is made to change travel behavior and the vehicles and fuels that provide mobility. While no individual ‘‘Silver Bullet” strategy exists that can achieve the goals, a portfolio approach that combines strategies could yield success. The 80in50 scenarios show the impacts of advanced vehicle and fuels technologies as well as the role of travel demand reduction, which can significantly reduce energy and resource requirements and the level of technology development needed to meet the target.  相似文献   

19.
Dramatic deteriorations in the future development of demographic and socio-economic factors having a decisive impact on public transport demand in 2000 - 2030 are predicted. How can a reasonable public transport service be maintained under these changing conditions? Depending on the entrepreneurial objectives defined individually by each public transport company a range of strategic actions must be taken in the field of offer and performance: Advancing strategies, consolidation strategies and defensive strategies are discussed with the stress laid on improving service in order to attract more ridership.  相似文献   

20.
The general international trend of increasingly subjecting the public transport industry to market principles has been concretized via various developments in many countries. In line with this trend, there is an increased interest in public procurement processes as a model for public service delivery. Sweden is one of the leading countries where public procurement is the prevailing model for delivering public services. In accordance with the general trend, efforts have been made to make Sweden’s public transport more sensitive to passenger needs, and to stimulate a competitive public transport system. For instance, a new Act, which came into effect on 1 January 2012, is aimed at fostering a customer-centric public transport system, with increased role clarity for the public transport actors. Since market-oriented strategies and public procurement processes are both receiving increased interest from the public transport industry, the market orientation of both public authorities and service providers in Sweden’s public transport has been studied. Since market orientation is a process of change, a longitudinal approach was whereby the first study was conducted in the spring of 2011 and the second in the spring of 2014. All of Sweden’s public transport authorities and the service providers that they stated as their major contract holders were asked to participate. In total, 184 respondents participated in the studies. The findings show that the industry as a whole has increased its organizational and inter-organizational efforts to both acquire knowledge of and respond to passenger needs. In particular, the public service providers have increased their involvement in market-oriented activities.  相似文献   

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