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1.
Abstract

Microscopic traffic simulators are the most advanced tools for representing the movement of vehicles on a transport network. However, the energy spent in traffic microsimulation has been mainly oriented to cars. Little interest has been devoted to more sophisticated models for simulating transit systems. Commercial software has some options to incorporate the operation of transit vehicles, but they are insufficient to properly consider a real public transport system. This paper develops an Application Programming Interface, called MIcroscopic Simulation of TRANSIT (MISTRANSIT), using the commercial microsimulator PARAllel MICroscopic Simulation. MISTRANSIT makes advances in three ways: public transport vehicles can have new characteristics; passengers are incorporated and traced as individual objects; and specific models represent the interaction between passengers and vehicles at stops. This paper presents the modelling approach as well as various experiments to illustrate the feasibility of MISTRANSIT for studying policy operations of transit systems.  相似文献   

2.
Reliability of a public transport operation is known to be an important measure of level-of-service for its patrons. It has been suggested that the reliability of a transit operation may be increased by regulating transit vehicles at various checkpoints to improve the schedule adherence of vehicles. It is possible to analyse changes in vehicle performance when checkpoint control strategies are introduced, as well as measure changes in level-of-service from the patrons' point of view, by using the TRAMS package to simulate the operation of a transit network. The simulation observations can also be used to determine optimum checkpoint control strategies.  相似文献   

3.
May  Anthony D.  Shepherd  Simon P.  Timms  Paul M. 《Transportation》2000,27(3):285-315
A new procedure for generating optimal transport strategies has been applied in nine European cities. A public sector objective function which reflects concerns over efficiency, environmental impact, finance and sustainability is specified and a set of policy measures with acceptable ranges on each, identified. Optimal strategies based on combinations of these policy measures which generate the optimal value of the objective function, are identified, and compared between cities. Resulting policy recommendations are presented. The results demonstrate the importance of an integrated approach to transport strategy formulation. They emphasise the role of changes in public transport service levels and of fares, and of charges for car use. By contrast, new infrastructure projects are less frequently justified. In the majority of cities the revenues from car use charges are sufficient to finance other elements in the strategy. However, private sector involvement either in initial financing or in operation may be desirable. Revised objective functions to reflect private sector involvement are specified, and optimal strategies with private sector operation of public transport are also identified. The requirement to meet private sector rates of return for public transport operation typically results in lower frequencies and higher fares; charges for car use then need to be raised to satisfy public policy objectives, but system performance is reduced. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   

4.
The existing studies concerning the influence of weather on public transport have mainly focused on the impacts of average weather conditions on the aggregate ridership of public transit. Not much research has examined these impacts at disaggregate levels. This study aims to fill this gap by accounting for intra-day variations in weather as well as public transport ridership and investigating the effect of weather on the travel behavior of individual public transit users. We have collected smart card data for public transit and meteorological records from Shenzhen, China for the entire month of September 2014. The data allow us to establish association between the system-wide public transit ridership and weather condition on not only daily, but also hourly basis and for each metro station. In addition, with the detailed trip records of individual card holders, the travel pattern by public transit are constructed for card holders and this pattern is linked to the weather conditions he/she has experienced. Multivariate modeling approach is applied to analyze the influence of weather on public transit ridership and the travel behavior of regular transit users. Results show that some weather elements have more influence than others on public transportation. Metro stations located in urban areas are more vulnerable to outdoor weather in regard to ridership. Regular transit users are found to be rather resilient to changes in weather conditions. Findings contribute to a more in-depth understanding of the relationship between everyday weather and public transit travels and also provide valuable information for short-term scheduling in transit management.  相似文献   

5.
Social equity is increasingly becoming an important objective in transport planning and project evaluation. This paper provides a framework and an empirical investigation in the Greater Toronto and Hamilton Area (GTHA) examining the links between public transit accessibility and the risks of social exclusion, simply understood as the suppressed ability to conduct daily activities at normal levels. Specifically, we use a large-sample travel survey to present a new transport-geography concept termed participation deserts, neighbourhood-level clusters of lower than expected activity participation. We then use multivariate models to estimate where, and for whom, improvements in transit accessibility will effectively increase activity participation and reduce risks of transport-related social exclusion. Our results show that neighbourhoods with high concentrations of low-income and zero-car households located outside of major transit corridors are the most sensitive to having improvements in accessibility increase daily activity participation rates. We contend that transit investments providing better connections to these neighbourhoods would have the greatest benefit in terms of alleviating existing inequalities and reducing the risks of social exclusion. The ability for transport investments to liberate suppressed activity participation is not currently being predicted or valued in existing transport evaluation methodologies, but there is great potential in doing so in order to capture the social equity benefits associated with increasing transit accessibility.  相似文献   

6.
Smart card data are increasingly used for transit network planning, passengers’ behaviour analysis and network demand forecasting. Public transport origin–destination (O–D) estimation is a significant product of processing smart card data. In recent years, various O–D estimation methods using the trip-chaining approach have attracted much attention from both researchers and practitioners. However, the validity of these estimation methods has not been extensively investigated. This is mainly because these datasets usually lack data about passengers’ alighting, as passengers are often required to tap their smart cards only when boarding a public transport service. Thus, this paper has two main objectives. First, the paper reports on the implementation and validation of the existing O–D estimation method using the unique smart card dataset of the South-East Queensland public transport network which includes data on both boarding stops and alighting stops. Second, the paper improves the O–D estimation algorithm and empirically examines these improvements, relying on this unique dataset. The evaluation of the last destination assumption of the trip-chaining method shows a significant negative impact on the matching results of the differences between actual boarding/alighting times and the public transport schedules. The proposed changes to the algorithm improve the average distance between the actual and estimated alighting stops, as this distance is reduced from 806 m using the original algorithm to 530 m after applying the suggested improvements.  相似文献   

7.
Downs (1962) and Thomson (1977) suggested that highway capacity expansion may produce counterproductive effects on the two-mode (auto and transit) transport system (Downs–Thomson Paradox). This paper investigates the occurrence of this paradox when transit authority can have different economic objectives (profit-maximizing or breakeven) and operating schemes (frequency, fare, or both frequency and fare). For various combinations of economic objectives and operating schemes, the interaction between highway expansion and transit service is explored, as well as its impact on travelers’ mode choices and travel utilities. Further, for each combination, the conditions for occurrence of the Downs–Thomson Paradox are established. We show that the paradox never occurs when transit authority is profit-maximizing, but it is inevitable when the transit authority is running to maximize travelers’ utility while maintaining breakeven. This is because the former transit authority tends to enhance transit service (e.g., raise frequency or reduce fare) when facing an expanded highway; and on the contrary, the latter tends to compromise transit service (e.g., reduce frequency or raise fare). Both analytical and numerical examples are provided to verify the theoretical results.  相似文献   

8.
This paper studies the effects of road pricing on land use under different development scenarios (business as usual scenario and transit oriented development scenario) by a quantitative method, which combines the integrated land use and transport interaction model (TRANUS model) with the scenario-planning techniques. Moreover, in order to further analyze the differences of the land use effects of road pricing on traffic analysis zones (TAZs) with different urban form attributes, a quantitative classification method combining factor analysis and cluster analysis is then used to quantitatively classify TAZs. The results demonstrate that the effects of road pricing on the land use of a specific region depend on the urban form attributes of the region. The higher the densities of employments and population, and better street design (high densities of street and intersections) and public transportation condition, the less the region is negatively affected by road pricing, and vice versa. More importantly, rail transit can alleviate the negative impact of road pricing on commercial development and population concentration of the region. Therefore, before introducing a road pricing policy, it is necessary to develop public transport system, especially rail transit.  相似文献   

9.
In the past decade public authorities have developed a wealth of creative funding mechanisms to support transit systems. This paper offers a taxonomy of various unconventional funding mechanisms (i.e. outside the domain of charges for transit passengers or general taxation schemes), based on a review of financial arrangements for public transport. The paper identifies which classes of funding are particularly successful for the financing of transit systems. This cross-sectional analysis uses a type of artificial intelligence method, viz. rough set analysis. It appears that the nature of the funding scheme and the degree of public acceptability are mainly responsible for the success of unconventional funding mechanisms.  相似文献   

10.
This paper presents an economic theory of the public transit firm that considers the public transit firm's operating objectives related to size maximization and cost minimization as well as its operating options and passenger quality-of-service characteristics. The theory indicates that the variables to be used in the performance evaluation of a public transit firm are its operating options and fare. A single measure for transit performance evaluation is the shadow price in maximizing passengers subject to an overall deficit constraint (to be financed by government).  相似文献   

11.
Social equity is increasingly incorporated as a long-term objective into urban transportation plans. Researchers use accessibility measures to assess equity issues, such as determining the amount of jobs reachable by marginalized groups within a defined travel time threshold and compare these measures across socioeconomic categories. However, allocating public transit resources in an equitable manner is not only related to travel time, but also related to the out-of-pocket cost of transit, which can represent a major barrier to accessibility for many disadvantaged groups. Therefore, this research proposes a set of new accessibility measures that incorporates both travel time and transit fares. It then applies those measures to determine whether people residing in socially disadvantaged neighborhoods in Montreal, Canada experience the same levels of transit accessibility as those living in other neighborhoods. Results are presented in terms of regional accessibility and trends by social indicator decile. Travel time accessibility measures estimate a higher number of jobs that can be reached compared to combined travel time and cost measures. However, the degree and impact of these measures varies across the social deciles. Compared to other groups in the region, residents of socially disadvantaged areas have more equitable accessibility to jobs using transit; this is reflected in smaller decreases in accessibility when fare costs are included. Generating new measures of accessibility combining travel time and transit fares provides more accurate measures that can be easily communicated by transportation planners and engineers to policy makers and the public since it translates accessibility measures to a dollar value.  相似文献   

12.
基于复杂网络的兰州市公交网络分析   总被引:1,自引:0,他引:1  
城市交通系统是一个动态的、自组织的、开放的复杂巨系统,交通拥挤等问题严重制约着城市有序、快速、高效地发展。文章基于复杂网络理论,以兰州市为例,运用Pajek软件和L空间法,构造了兰州市公交站点网络,并对公交网络的度、累积度和聚类系数进行了分析。结果表明,兰州市公交站点网络具有无标度特性。  相似文献   

13.
Transit operators face a difficult fiscal environment and an imperative to contribute to urban sustainability. Under these circumstances, operators must find innovative ways to make public transportation attractive to broader segments of the public, while simultaneously trying to raise revenue to reduce reliance on public subsidies. Development of commercial partnerships is seen as a promising way to achieve these goals. Previous research has examined the potential of using geodemographics to assist transit agencies in the task of identifying potential partners for developing mutually beneficial commercial agreements. In this paper we describe an approach to model isoexposure to transit users as a tool to assess market potential. The approach is based on the analysis of walking behavior of transit users, and specifically distance walked at the end of their transit trip. Spatial modeling is used to geographically project estimates of walking distance for a desired demographic profile at a specific transit facility. After expanding the estimates using sample weights, overlays of these estimates can be used to generate variations in exposure to transit travelers at different locations in space. The approach is demonstrated using the case of Metro users in Montreal, Canada. The case study demonstrates the use of isoexposure profiles as a novel approach to generate marketing intelligence. This should be of interest to transit agencies and businesses interested in developing partnerships.  相似文献   

14.
Sustainable land use planning and advanced public transport system are believed to be effective solutions to traffic congestion. To this end, it is important to reveal the relationship between transit ridership and land use. However, current Direct Ridership Models only focus on the relationship between single station's boarding volume and the corresponding catchment area land use. This paper analyzed the ridership distribution between transit stations by considering the land use difference between catchment areas. Land use difference was calculated from point of interest (POI) data extracted from an electronic map of Beijing; transit trip distribution volume was obtained from ‘automatic fare collection’ facility. After data specification, a transit ridership distribution model was proposed and calibrated. The calibration results suggest that land use difference has a directly proportional correlation with transit ridership distribution. The research findings build a bridge between detailed urban form and public transport, which is of significance for the further research of sustainable urban planning. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   

15.
步晓庆 《综合运输》2021,(1):104-109
在"一带一路"战略背景下,铁路物流中心的公铁联运业务至关重要。公铁联运业务各主体的协同存在易变性,资源双方是否信任会影响各自的策略选择。本文以铁路运输企业为主导,铁路运输企业接到客户公铁联运订单时会借助平台发布公路运输需求信息,公路运输企业根据自身情况向铁路运输企业表达意愿,最后铁路运输企业根据其采取的策略找到自身是否接受合作的均衡条件。本文通过对公、铁运输企业的短期博弈分析,找到双方合作的均衡条件,为双方利益分配奠定基础。  相似文献   

16.
17.
Little is known about the sources of public support for transit systems even though the perceptions of transit users and potential users have been extensively documented. Research reported here examines dimensions of public support for the first U.S. downtown people mover during three critical phases in the system's life: construction, shakedown, and operations. The method employed was a community sample survey with home interviews. Data analysis showed that the public—who were virtually all nonusers—were largely favorable toward the system during the construction phase. During the shakedown phase, when system reliability was extremely low, many attitudes toward the system became less favorable, especially perceptions of performance and direct community impacts. Later, reliability improved, and attitudes which had become less favorable tended to grow more favorable once again. It is suggested that a system's performance can influence many aspects of public support for a transit system, even among nonusers. This pattern has implications for system planners who must depend on public good will for continuing support of transit systems. In particular, extensive pretesting of new systems should occur before the fare gates are opened to patrons.  相似文献   

18.
19.
The importance of measuring customer satisfaction for a public transport service is apparent, even beyond more immediate marketing purposes. The present paper shows how satisfaction measures can be exploited to gain insights on the relationship between personal attitudes, transit use and urban context. We consider nine satisfaction measures of urban transit services, as expressed by a representative sample of Italian multimodal travelers (i.e. users of both private cars and public transport). We use correlations and correspondence analyses to show if and how each attribute is related to the levels of use of public transport, and how the relationship is affected by the urban context. Then we apply a recently developed method to combine ordinal variables into one score, by adapting it to work with large samples and with satisfaction measures which have a neutral point in the scale (i.e. “neither satisfied nor dissatisfied”). The resulting overall satisfaction levels and frequency of use were not correlated in our sample. We also found the highest satisfaction levels in smaller towns and the lowest ones in metropolitan cities. Since we focus on multimodal travelers, an interpretation paradigm is proposed according to which transit services must be well evaluated by car drivers in smaller towns in order to be considered a real alternative to cars. On the other hand, transit is more competitive on factual elements in larger cities, so that it can still be used by drivers, even if it is not very well evaluated.  相似文献   

20.
This paper focuses on four issues. The first is the case of one-sided investments in mass transit in metropolitan areas of developing countries. It is pointed out that in many cases in which the conditions for optimum investment policies (Pareto's Optimum) are not maintained, excessive investments on mass transit, including large annual operating subsidies, usually lead to substantial sub-optimizations and waste of scarce financial resources. This problem is then reviewed under the light of the “Theory of Second Best” as articulated for all investment options within Welfare Economic Theory. The second issue examined is the matter of recently discovered important diseconomies of scale of large metro transit systems in developing and developed countries, and the need to retain production of transport services within small-scale production units that are well coordinated and controlled. The third issue discussed is the problem of mismanagement of most public sector transit companies and agencies. The notion that most such systems are simply administered, not managed, is being brought up and the requirements for proper management are amplified. Finally, the case of public vs. private ownership of mass transit is being discussed with a distinction between public policies of providing mass transit services and the actual production process of these services. Provision of services represents a public responsibility that belongs to the public sector. However, production of service is a techno-economic process that requires different talents and circumstances. The paper concludes with a strong suggestion for major reorientation of urban mass transit in the metro areas of developing countries towards more efficiency and higher productivity.  相似文献   

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