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1.
In this paper, a “by transit accessibility (BTA)” measure to evaluate the impacts of travel distance and transfer tolerance on the convenience of commuting by transit on a regional scale is proposed. Considering the spatiotemporal factors for commuting efficiency evaluation, the timetable-dependent passenger carrying capacity of the transit station and the time-varying passenger demand at originating sites have been formulated into the BTA model. Moreover, the proposed BTA measure could reflect the commuting trip demand elasticity, which is caused by travel distance and transfer tolerance. In the meantime, this BTA measure can provide an important basis for transit timetable adjustment in the study area during different time periods. The proposed measure is tested on a small transit network to display its function, and finally, it is applied to an empirical case to draw practical findings.  相似文献   

2.
The trilogy of distance, speed and time   总被引:1,自引:0,他引:1  
Over the recent past there has been a dramatic increase in travel, mainly driven by the desire to move faster and over ever greater distances. This growth is unsustainable, and the continued growth in levels of mobility needs to be reassessed through substantially reducing the levels of consumption (energy and carbon) in transport. This means that travel activities should be based on shorter distances and slower speeds, with a more flexible interpretation of time constraints. Transport geographers should have a strong and instrumental role to play in this debate. This paper outlines the changing patterns of movement, before concentrating on urban areas where most daily travel takes place, and it examines the trilogy of distance, speed and time. The focus of the paper is on distance, and the role that land use planning and development, and technology can play in encouraging new forms of travel in cities, but there are strong implications on the ways in which speed and time are conceptualised. The conventional transport paradigm is heavily embedded in the belief that travel time needs to be minimised and consequently speeds need to be increased. The resulting impacts on travel distances have not been part of that debate, but reducing travel distances is central to sustainable transport.  相似文献   

3.
Accessibility to transit, together with other important system characteristics such as network coverage and frequency, is a crucial driver of modal choice for urban commuting. In turn, commuting is a major driver of energy consumption and of socio-environmental externalities in cities. So far, few quantitative and comparative assessments of paratransit in cities of Africa have been carried out due to data scarcity and the prevalence of informal services. Here we leverage the recent release of General Transit Feed Specification (GTFS) data to produce comparative metrics of accessibility, network, and service quality of paratransit in seven major cities in sub-Saharan Africa (Abidjan, Accra, Addis Ababa, Freetown, Harare, Kampala, Nairobi). Our results allow for a first-order assessment and comparison of different crucial paratransit characteristics in these cities, shedding light on transport inequality and urban segregation dynamics. The analysis and metrics produced can support transport systems planners in major cities of low-income countries. Further research should focus on approaches for overcoming the residual data limitations and expand the quantitative understanding of paratransit.  相似文献   

4.
This paper tries to break new ground in how distance-decay relationships are modelled in accessibility and transport demand studies and does it based on an innovative approach to empirical data collection on psychological perceptions of distance in relation with activities located in space and a new aggregate distance-decay function. This new approach improves on the quality of the representation of spatial interaction effects on transport demand modelling studies that commonly rely on generic curves barely confronted with empirical data. We compare the level of fit of the proposed curve with other distance-decay functions mentioned in the literature and used in practice and draw relevant conclusions on the proper model specification.  相似文献   

5.
6.
A number of transportation infrastructure projects were conducted in Europe during the 1990s with the explicit objective of promoting regional cohesion goals through the improvement of the accessibility of peripheral regions. Given its peripheral situation in the Union, Portugal was a key target for some of these projects. A decade later, it is pertinent to ask whether the new infrastructure achieved its objective of promoting lagging regions. The objective of this paper is to analyze one of the lagging regions in Portugal, to try to establish the link between changes in accessibility levels brought by improvements in the transportation network, and two indicators commonly used in accessibility research (population and purchasing power), while controlling other variables of possible relevance, such as the levels of educational achievement of the population in the region. The analysis is based on the use of spatially autoregressive models which allow the representation of accessibility as spatially lagged variables of first and second order. The results place the contribution of accessibility changes in context, and point at the relevance of education as an alternative policy.  相似文献   

7.
This paper approaches the airport location problem as a function of accessibility considerations. First, a structural equation model is established to find the relationship between the size of an airport catchment area and its flight network scale. Landside and airside accessibilities are measured by the qualities and costs of surface transportation and flight networks. The two accessibilities are combined to form a regional air transportation accessibility profile, which can be used as a criterion to evaluate airport locations at a macro-planning level. Finally, the scenarios of airport locations in terms of small and large areas are analyzed using two regional case studies in China.  相似文献   

8.
The regional differences in the level of accessibility and GDP per capita in Europe are the subject of many scientific analyses and much applied research. Using the road network for the whole continent and the division of Europe into transport areas on the basis of NUTS 3, we have concentrated on the potential quotient as a research method. The quotient is a ratio of economic and population potential, and its level and spatial distribution differ based on the dimensions of accessibility: spatial scope (intra-European and intra-national) and impedance. Depending on the variants of the above-mentioned accessibility dimensions, we focus on analysis of the core-periphery pattern. Based on a comparison of the level of GDP per capita with the level of potential quotient, we define the discontinuity belts in the cross-border areas and in urban agglomerations, i.e. areas particularly sensitive to migratory movements or commuting to work. In turn, the analysis of regional differences in the level of the potential quotient for different travel durations and, as we call it in the paper, the value of the CATCH-time, leads us to show the so-called tornado effect which is associated with declining spatial polarisation as a result of the extension of trip distribution towards longer trips. The typology presented describing the relationship between GDP per capita and the level of potential quotient at different spatial scales and for different trip durations allows the identification of regions particularly exposed to migration or interregional commuting flows and is a good premise for defining inner peripheries.  相似文献   

9.
The paper draws together results from several major revealed preference (RP) and stated preference (SP) data sets, collected for large-scale disaggregate models and VTTS research, respectively, to comment on trends which appear in time and cost trading as between different time periods and different countries.  相似文献   

10.
This paper contributes to the airport benchmarking literature in two ways. To our knowledge, this is the first attempt at using a stochastic distance function to measure airports’ productivity changes while considering multiple outputs. Secondly, we calculate the evolution and decomposition of the Total Factor Productivity (TFP) for Spanish airports. The average rate of productivity showed a slight annual improvement of 0.9%, and the core engine of this was 3% increase in technical progress rather than through efficiency. Results, by airport, identify those needing improvement, to be more attractive in the Spanish airport restructuring program.  相似文献   

11.
Approximately one-fifth of Perth’s population is aged 60 or older. Projections suggest that this proportion will continue to increase as a result of the large number of children born after the World War II (1946–1964). Access to and accessibility around train stations for the aging population is and will become a more important issue as the elderly population continues to grow. The aim of the paper is to develop and apply a new measure of accessibility to train stations at a fine spatial scale, justified by the special circumstance of the elderly using a case study in Perth, Western Australia. Intercept surveys are used to collect data on factors affecting train station accessibility for patrons aged 60 years or older, at seven highly dispersed train stations. Overall accessibility is measured separately using a composite index based on three travel modes (walk-and-ride, park-and-ride and bus-and-ride). The results illustrate that key variables, such as distance from an origin to a station, walking or driving route directness, land-use diversity, service and facility quality, bus connection to train stations, all affect the accessibility to train stations for the elderly. This implies that improvements to these factors will improve accessibility for this population group.  相似文献   

12.
How transport and employment agglomeration enhance urban productivity is a fundamental problem for many cities. Internationally, there has been a great deal of interest in the effect of employment concentration on urban productivity, but very few studies have examined its effect on worker commuting burdens and transport costs. This paper aims to advance international knowledge by measuring job growth and costs of labour market access between 2011 and 2016 for employment centres (EC) in Melbourne, Australia. A comprehensive transport cost model is used that incorporates detailed transport costs and travel times associated with transport modes. By tracking job growth and changes in worker commuting burdens, this paper distinguishes ‘high-cost’ ECs from ‘low-cost’ ECs, for their respective labour pools, and identifies which ECs offer opportunities for better transport outcomes. The results show that well-planned public transport (PT) systems and residential development, coupled with walking and cycle networks, are important features of ECs experiencing lower commuting burdens. Drawing upon the conclusions, this research recommends more effective approaches by governments to foster effective investments in urban infrastructure and discusses how broader policy and investment decisions can align to optimise employment agglomeration and minimise negative transport impacts.  相似文献   

13.
Seaports have traditionally been the focus of maritime logistics supply chains. Changing production patterns demanding greater end to end visibility by customers and accessibility to key inland population centers assume greater importance in the organization and design of transport resources and cargo flows. While synchronization of all aspects of the supply chain has become an operational necessity for firms, it is often held hostage to the efficiency of hinterland networks who must respond to a large group of stakeholders with sporadic coordination. This is particularly true when looking at the central US city and region of Chicago, a critical intermodal exchange point for truck, air and river barge traffic domestic and global, as well as a major central distribution location. This paper analyzes supply chain integration (SCI) efforts in the metropolitan Chicago region and considers efforts by public and private actors to collaborate for region-wide SCI improvements. Pareto analysis suggests that concentrated freight corridors exist, influencing freight planning for regional transportation networks more directly than diffused regional freight movements. If the corridor service becomes less responsive or congested the corridor will move to different end nodes within the broad region. Regional planning must thus address national, regional, and local moves. Private/public sector infrastructure firms should address functional cooperation on SCI by focusing on corridors as well as local improvements.  相似文献   

14.
The accessibility impacts of transport projects ex-post implementation are generally evaluated using cumulative opportunity measures based on a single travel time threshold. Fewer studies have explored how accessibility appraisal of transport plans can be used to evaluate policy scenarios and their impacts for different social groups or examined whether the results of project appraisals are sensitive to the time threshold of choice. This paper analyzes how different scenarios of full and partial implementation of the TransBrasil BRT project in Rio de Janeiro (Brazil) will likely impact the number of jobs accessible to the population of different income levels. The analysis is conducted under various travel time thresholds of 30, 60, 90 and 120 min to test whether the results are sensitive to the boundary effect of the modifiable temporal unit problem (MTUP). Compared to a partial operation scenario, the full implementation of TransBrasil that extends this corridor into the city center would lead to higher accessibility gains due to network effects of connecting this BRT to other transport modes. Nonetheless, the size of the accessibility impacts of the proposed BRT as well as its distribution across income classes would significantly change depending on the time threshold chosen for the accessibility analysis. Considering cut-off times of 30 or 60 min, both scenarios of TransBrasil would lead to higher accessibility impacts in general and particularly for low-income groups, moving Rio towards a more equitable transportation system. However, under longer thresholds of 90 and 120 min, an evaluation of this project would find much smaller accessibility gains more evenly distributed by income levels. The paper highlights how time threshold choice in cumulative opportunity measures can have important but overlooked implications for policy evaluation and it calls for further research on the MTUP in future transport and mobility studies.  相似文献   

15.
While adequate integration of land use and transport is seen as crucial for achieving sustainable outcomes, the reciprocal interconnection between retail activity and non-motorised accessibility is yet to be adequately examined. To address this gap, this paper proposes the concept of Retail Mobility Environment (RME) and develops a methodological process for identifying and mapping RMEs, using the city of Zaragoza, Spain, as a case study. The concept of RME is developed through three methodological phases: (i) definition of non-motorised Accessibility Zones (AZs), using three indicators (walking accessibility, bicycling accessibility, betweenness); (ii) definition of Retail Zones (RZs), also using three indicators (retail density, retail diversity, retail contiguity); and (iii) definition of RMEs, where both retail activity and non-motorised indicators were weighted and combined using multi-criteria analysis. In total, four RMEs were identified and mapped: short-distance environments, motorised environments, non-motorised environments, and long-distance environments. The paper concludes with a discussion on the need to unravel the relationships between retail activity and non-motorised accessibility, in order to reach sustainable planning goals, as well as the potential usefulness of RMEs for transport policy-making.  相似文献   

16.
In this paper we consider vendor-buyer channels subject to trade credit and quantity discounts for freight cost. We deal with the problems of determining the vendor’s credit period, the buyer’s retail price and order quantity while still maximizing profits. We focus on how channel coordination can be achieved using trade credit and how trade credit can be affected by quantity discounts for freight cost. We show that profits for both parties increase under channel coordination when the credit period is kept within an appropriate range. This range becomes wider as the discount for freight rates increases.  相似文献   

17.
The average commuting distance in Finland has increased steadily during recent decades. Daily long-distance commuting especially increases the number of vehicle-kilometres travelled. The aim of this work was to determine the relationship between commuting distance and frequency. The focus was on direct impacts of telework on commuting, but the significance of second apartments close to the workplace was also estimated. The empirical analyses were based on aggregate national data concerning commuting distances and a survey providing data of 19 000 employed respondents. The results of the study indicated that telework reduced by 0.7% the total kilometres travelled in Finland. The probability of working at home increases with commuting distance, but when the commuting trip exceeds 100 km a second apartment near the workplace becomes common and has a stronger impact on commuting kilometres travelled than telework.  相似文献   

18.
Lack of cross-border transport supply has repeatedly been blamed for the fact that national borders limit spatial interaction and, consequently, the growth of border regions. This study applies an accessibility approach to investigate for most municipalities in ten countries in mainland West Europe if foreign transport supply is lagging behind, and if population growth in these municipalities has been affected by the limits that national borders have imposed on market access. To do so, data describing historical population changes and road networks between 1961 and 2011 have been used. The results show that in the study area, cross-border transport accessibility was not at a disadvantage in 1961 and has since then grown even more than domestic accessibility. However, municipal population growth has depended almost exclusively on domestic market access. Processes of economic international integration in the study area are found to coincide with the growth of cross-border accessibility, but do not have a clear coincidence with the effects of cross-border accessibility on population growth.  相似文献   

19.
Indoor environments are increasingly important spaces in contemporary three-dimensional cities. Handling these micro-scale spaces within the broader context of outdoor - urban environments is a significant challenge in transportation analysis and geographic information science. This complexity stems from the greater computational requirements, the specificity of indoor network data structures, as well as the inherent perceptual intricacies of 3D visualization. As built environments grow in size and in complexity, two-dimensional urban geography research reveals its limits. This paper advocates for 3D network-based urban research and showcases the feasibility of this approach for three specific types of urban analytical functionalities, namely route planning, spatial accessibility assessment, and facility location planning. The latter modeling functionality can be viewed as foundational elements for comprehensive network-based three-dimensional analytics of urban environments. The effectiveness of the data modeling scheme and of the integrated software application 3DCityNet is discussed through the three coupled geospatial modeling functionalities.  相似文献   

20.
This paper presents an analysis of the spatial characteristic of the modal accessibility gap (MAG) in Guangzhou based on travel times for public transport and cars to public centers calculated by the Travel O-D point Intelligent Query System (TIQS). Four spatial regression models are used to investigate the effect on the MAG of six factors of the built environment (distance to city public centers, residential density, landuse mix, bus stop density, metro station density and road network density). The results show that travel time for a given origin to destination (OD) trip is likely to be larger by public transport than by car, especially for a trip of longer travel time. The MAG values of all the communities are larger than 0, indicating that when compared with public transport, travelling by car takes less travel time for individuals. Residential density, land-use mix, bus stop density and metro rail station density have significant negative direct impacts and indirect impacts (spatial spillover effects) on MAG, which indicates that appropriate increase in community residential density, providing diversified service facilities within a community, and improving public transport supply are beneficial to promote modal shift. Specifically, the role of metro rail is greater than that of buses. However, the road network density has significant direct positive impacts on MAG, and its spillover effect is also significantly positive, which indicates that building more roads is not an effective way to narrow the accessibility gap between public transport and cars but may facilitate more car travel instead.  相似文献   

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