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931.
水面无人船的发展与使命(英文)   总被引:5,自引:0,他引:5  
  相似文献   
932.
This paper focuses on recent experiences in the evolution of Flexible Transport Services (FTS). It describes how previous manifestations of FTS provided dedicated solutions for special groups, often in parallel to the conventional public transport network, but highlights that in numerous countries across Europe there is now a discernable trend towards open access FTS providing services for the whole community and often feeding the conventional public transport network to provide wider access and opportunities. This is as a result of policies intended to mainstream services for people with disabilities and moves to tackle social exclusion amongst other groups while at the same time reducing the very high costs per trip associated with STS.To meet these policies, and the higher expectations and different travel behaviours of citizens to-day, it is suggested that FTS will need to radically reposition itself in terms of scale, so that there is mass coverage and ability to function as a full transport mode. This will require breakthroughs in concepts; business models; organisational and operational models; and in supporting technologies. A proposed solution to this is the Flexible Agency for Collective Mobility Services (FAMS) which provides an organisational structure and business model for FTS that incorporates the required supporting technologies.  相似文献   
933.
Mass transit projects are often a top contender of many cities to meet their increasing demand for travel. Despite the global trend of privatization, mass transit services, as public goods, remain largely being provided and operated by the public sector. Hong Kong is one of the few exceptions that all mass transit services are commercially operated. Both rail and bus services in Hong Kong are reputable for their quality and profitability, often serving as benchmarks for new projects. In this study, we investigate the factors contributing to this success. In particular, we ascertain the quality of transit service provision by the private sector over the past two decades. Then, we conduct an in-depth analysis of the account books of leading railway and bus operators in Hong Kong so as to shed light on their financial viability. Through this study, we hope to present crucial factors for providing financially viable private transit services.  相似文献   
934.
Although people are often encouraged to use public transportation, the riding experience is not always comfortable. This study uses service items to measure passenger anxieties by applying a conceptual model based on the railway passenger service chain perspective. Passenger anxieties associated with train travel are measured using a modern psychometric method, the Rasch model. This study surveys 412 train passengers. Analytical results indicate that the following service items cause passenger anxiety during trains travel: crowding, delays, accessibility to a railway station, searching for the right train on a platform, and transferring trains. Empirical results obtained using the Rasch approach can be used to derive an effective strategy to reduce train passenger anxiety. This empirical study also demonstrates that anxiety differs based on passenger sex, age, riding frequency, and trip type. This information will also prove useful for transportation planners and policy-makers when considering the special travel needs of certain groups to create a user-friendly railway travel environment that promotes public use.  相似文献   
935.
This paper seeks to explore the relationship between mode and destination choice in an integrated nested choice model. A fundamental argument can be made that in certain circumstances, the ordering of choices should be reversed from the usual sequence of destination choice preceding mode choice. This results in a travel demand model where travelers are more likely to change destinations than to change transportation modes. For small and medium size urban areas, particularly in the United States, with less well developed public transit systems that draw few choice riders, this assumption makes much more sense than the traditional modeling assumptions. The models used in the new travel modeling system developed for Knoxville, Tennessee utilize this reversed ordering, with generally good results, which required no external tinkering in the logsum parameters.  相似文献   
936.
937.
This paper proposes a new activity-based transit assignment model for investigating the scheduling (or timetabling) problem of transit services in multi-modal transit networks. The proposed model can be used to generate the short-term and long-term timetables of multimodal transit lines for transit operations and service planning purposes. The interaction between transit timetables and passenger activity-travel scheduling behaviors is captured by the proposed model, as the activity and travel choices of transit passengers are considered explicitly in terms of departure time choice, activity/trip chain choices, activity duration choice, transit line and mode choices. A heuristic solution algorithm which combines the Hooke–Jeeves method and an iterative supply–demand equilibrium approach is developed to solve the proposed model. Two numerical examples are presented to illustrate the differences between the activity-based approach and the traditional trip-based method, together with comparison on the effects of optimal timetables with even and uneven headways. It is shown that the passenger travel scheduling pattern derived from the activity-based approach is significantly different from that obtained by the trip-based method, and that a demand-sensitive (with uneven headway) timetable is more efficient than an even-headway timetable.  相似文献   
938.
In this paper we review freight forecasting models and current advances and needs with respect to data and model development. We then present a case study to suggest which models should be developed for the State of California in the US. We suggest several alternatives including an aggregate commodity flow model, a disaggregate regional logistics model and a hybrid regional logistics model with a truck touring model. We point out however, that the data requirements for the latter model would be extensive. In addition, the development of hybrid models, for example progress in the integration of regional logistics models with urban truck touring models, will introduce new problems such as reconciling the outputs of multiple models for consistency.  相似文献   
939.
A new model system dealing with trips of length up to 100 km has recently been developed in Norway. A new way of dealing with seasonal passes for public transport is used in the travel-to-work model. The objective was to account for the fact that a respondent that posses a seasonal pass for public transport may behave as if public transport is free on the day they report a travel diary. On the other hand, we can not assume that public transport is free for respondents that used other modes of transport or that public transport is free to alternative destinations. This problem was solved by defining seasonal pass as a separate alternative in the form of a nest that included all modes of travel. The cost of a seasonal pass is a common cost for all modes in the nest and will thus not affect the choice within the nest. The estimation of this specification is compared with the more common approach of assigning an average cost per day based on the cost of a monthly pass and the number of workdays in a month. The comparison indicates that the “average cost per day” approach may produce biased estimates for several parameters. It also turns out that the cost parameter for seasonal pass is higher than the parameter for “out of pocket” cost, probably reflecting that there will be some uncertainty with respect to the actual use of a seasonal pass.  相似文献   
940.
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