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1.
This study investigates how urban form is related to accessibility. In particular, it explores the relationship between Transit-Oriented Development (TOD) and rail-based accessibility in a metropolitan area. The following overarching questions are addressed: Does a TOD-informed urban spatial structure correlate with high rail based accessibility? Which features of TOD are correlated to rail-based accessibility? These questions are answered through a comparative analysis of six metropolitan areas in Europe. The “TOD degree”, operationalized as the extent to which urban development is concentrated along rail corridors and stations, is correlated with a cumulative opportunity measure of rail-based accessibility to jobs and inhabitants.The comparison demonstrates that rail-based accessibility is higher in urban areas where inhabitants and jobs are more concentrated around the railway network and in lesser measure in urban areas with higher values of network connectivity. No correlation is found between rail-based accessibility and average densities of inhabitants and jobs.  相似文献   

2.
As accessibility becomes an increasingly relevant concept in the analysis of sustainable transport and urban development, the accuracy of accessibility measures becomes increasingly vital. While more complex measures are gradually gaining popularity with increasing data and computational resources, policy makers and planners are still prone to opt for less complex methods that are easy to use and interpret. The cumulative opportunities measure is the most widely applied accessibility measure in planning practice, but it is also among the least accurate due to its lack of consideration of the impact of competition for those opportunities. This study seeks to highlight the impact of addressing competition for different urban services in the cumulative opportunities measure. A competition component is added to the measure, which is applied to a case study of three types of urban services in the Perth metropolitan area; jobs, primary/secondary education and shopping. The results show that considering competition changes the spatial patterns of accessibility and its equity. Since this approach reveals demand-supply imbalances, it can more accurately determine spatial inequalities in accessibility, and hence increases the utility of the cumulative opportunities measure. We also find that the three services had varying levels and spatial patterns of accessibility and spatial equity, thus relying on any single one of them for assessing spatial structural performance can be misleading.  相似文献   

3.
The construction of the fixed link between Denmark and Sweden will increase the accessibility between South Sweden and East Denmark dramatically. The vision is that the fixed link will span economic, administrative, institutional, technical, cultural and other barriers, and that the two separated urban systems (Greater Copenhagen and Malmö–Lund) can be integrated, opening up for new dynamics. The Öresund (Sound) area has the potential to develop into one functional metropolitan region constituted by flows, markets and terminals. The ambition is to lift Copenhagen to a higher position in the European urban hierarchy by this integration, the instrument being the 16 km long fixed link which will open in the year 2000.  相似文献   

4.
Many US metropolitan areas have undergone dramatic shifts in socioeconomic organization.. As urban areas gentrify, many low-income residents and communities of color have transitioned towards the exurban periphery. These suburban neighborhoods tend to have fewer employment opportunities and are fairly disconnected from public transportation networks serving the urban core. Using regional transportation plans (RTPs) for three California MPOs, we show that the transportation accessibility and environmental health issues affecting these exurban communities are unique and inadequately captured by the MPOs' current equity metrics. MPOs performance evaluation is regional and achieving equity within the urban core communities will not address emerging equity, accessibility and air quality concerns for exurban communities. With a brief history and a focused case study of RTPs for the San Francisco Bay Area, San Diego, and Fresno, we examine how air pollution, equity, and transportation interact in three different types of 21st century cities. We find that when allocating limited transportation funds, California metropolitan planning organizations (MPOs) prioritize the improvement of existing public transportation in urban core areas over expansion of transit networks towards disconnected exurbs. This approach is an effective way to reduce vehicle miles traveled (and thus, air pollution) at the regional level due to high population concentrations in urban cores. However, this approach also concentrates the air quality benefits of VMT reduction in these same urban core areas. Exurban residents' on-road and near-road exposure to Traffic-Related Air Pollution (TRAP) will not be reduced by improving public transit within the urban core. We argue that although these suburban and exurban communities are a small percentage of the regional population, they have a right to share in the benefits of transportation investments, particularly given the historical and ongoing patterns of displacement and economic exclusion from urban core areas.  相似文献   

5.
This study investigates the redistributive effects of Seoul's bus rapid transit (BRT) system on development patterns and property values using an urban simulation model. The Seoul Metropolitan Integrated Urban Model (SMIUM) combines the Seoul metropolitan input-output model with random utility-based location choice models and endogenous real estate markets.The major findings of this study can be highlighted as follows. First, Seoul's BRT contributes to increased development density in urban centers, acting as a centripetal force to attract firms from the suburbs into urban cores and supporting arguments for Smart Growth proponents. Second, unlike its redistributive effects on nonresidential activities, the BRT has a limited effect on the redistribution of residential activities, implying that residential locations are less sensitive to accessibility improvements made by the BRT than are nonresidential locations. Third, reflecting the transferred space demands from the suburbs to the urban cores, the CBD reaps the highest property value gains, while all of the outer ring zones suffer from reduced property values.  相似文献   

6.
Different measures of cycling accessibility have been widely introduced in transportation planning. However, those measurements are mainly restricted by the availability of travel behavior data. In addition, there has been limited comprehensive research on the importance of cycling accessibility to destinations based on the travel time or distance. In this paper, a new index for measuring bikeability in metropolitan areas is introduced. A Cycling Accessibility Index (CAI) is developed for quantifying cycling accessibility within local areas in metropolitan Melbourne, Australia. CAI is defined according to gravity-based measures of accessibility. This index measures cycling accessibility levels in terms of diversity of different land uses, number of activities in statistical areas, and the travel impedance between origins and destinations. The Victorian Integrated Survey of Travel and Activity (VISTA) dataset was used to evaluate the index and investigate the association between the cycling accessibility levels and the number of bicycle trips in local areas. The index is assessed by investigating the association between levels of cycling accessibility and the number of bicycle trips in statistical areas. Key findings indicate that there is a significant positive association between bike trips and the CAI.  相似文献   

7.
The urban growth of large cities in China is at a critical stage with the booming of the economy and impressive increase of the population and traffic demand. This paper studies and qualifies the growth and accessibility of a rapid rail transit network, and characterizes the relations with urban development using a spatio-temporal modelling approach. Several measures of the network topological structure, i.e., beta index (β), cyclomatic number (μ), alpha index (α) and gamma index (γ), are selected in order to examine and quantify the overall metro network growth of the city of Guangzhou in China. The results show that the current spatial connectivity of the Guangzhou’s metro network is relatively low, this stressing the need to augment the reliability of the connections between the network nodes, and to increase the number of circuits in the network. A travel-time matrix is modelled and evaluates the nodes accessibility and characterizes the spatio-temporal evolution of the metro network. The spatial interaction between the different nodes of the network, as well as nodes accessibility are analyzed and derived from a potential-based model. The extension of the metro network clearly shows a dramatic tendency of positive accessibility evolution but with regional differences. In particular, the core of the city is surrounded by areas with highest accessibility values and gradually expanding outward from the core, while the locations of transfer stations have significant influence on the variation of network time-based accessibility. Taking into account different network development scenarios, the approach reveals regional accessibility differences in the metropolitan area of the city of Guangzhou, this clearly illustrating the impact of network accessibility in urban development.  相似文献   

8.
This paper investigates the circuity of transit networks and examines auto mode share as a function of circuity and accessibility to better understand the performance of urban transit systems. We first survey transit circuity in the Minneapolis–St. Paul, Minnesota, region in detail, comparing auto and transit trips. This paper finds that circuity can help to explain mode choices of commuters. We then investigate thirty-five additional metropolitan areas in the United States. The results from these areas show that transit circuity exponentially declines as travel time increases. Moreover, we find that the circuity of transit networks is higher than that of road networks, illustrating how transit systems choose to expand their spatial coverage at the expense of directness and efficiency in public transportation networks. This paper performs a regression analysis that suggests the circuity of transportation networks can estimate transit accessibility, which helps to explain mode share.  相似文献   

9.
Improving public transport accessibility can be considered an effective way of reducing the external costs and negative side effects of motorized commuting. Although there have been many studies conducted that have measured access levels to public transport stops/stations, there has been limited research on measuring accessibility that integrates population density within geographical areas. This study develops a new measure that considers public transport service frequency and population density as an important distributional indicator. A public transport accessibility index (PTAI) is formulated for quantifying accessibility within local areas in metropolitan Melbourne, Australia. A public transport network model is applied to identify the service coverage of public transport modes using a Geographical Information System (GIS). A consistent method is introduced for evaluating public transport accessibility for different levels of analysis, from single elements, including public mode stops to network analysis. The Victorian Integrated Survey of Travel and Activity (VISTA) is used to evaluate the index and examine the association between commuting trips undertaken by public transport and the level of accessibility within the Melbourne metropolitan region. Furthermore, the new index is compared with two existing approaches using the VISTA dataset. Key findings indicate that the PTAI had a stronger association whilst showing more use of public transport in areas with higher values of the PTAI.  相似文献   

10.
Transportation scholars are challenging traditional formulations of the spatial mismatch hypothesis because previous studies have disregarded the considerable difference between travel modes. This case study of the Detroit metropolitan region uses 2000 census data and a gravity-based model of transportation accessibility to test differences in access to jobs among places and people, and provides support for recent calls for reconceptualizing spatial mismatch. It shows that even though Detroit experiences the greatest distance between African Americans and jobs of any region in the country, most central city neighborhoods offer an advantage in accessibility to jobs compared to most other places in the metropolitan region – as long as a resident has a car. Policies aimed at helping carless people gain access to automobiles may be an effective means of improving the employment outcomes of inner-city residents.  相似文献   

11.
The Metrocable in Medellín, Colombia, is an innovative system to improve access to deprived areas located in hilly zones. The idea to use cable cars as feeders to the metro was integrated into an ambitious urban project that, to date, has improved accessibility dramatically for some low-income residents. Using data before and after the project’s implementation, we evaluate the impact on social equity for the population in the zone of influence, considering changes in accessibility to employment and in housing-related costs. The access provided by the project to the main high-employment centres has doubled the number of opportunities that can be reached by the “target population,” even though travel-time savings and costs have seen only small changes. In fact, prior access to the CBD was poor and expensive, but time and costs were reduced with the Metrocable, although this reduction was not equal for all locations in the metropolitan area. In general, we argue that the main benefits, in terms of accessibility that differentiates the areas analysed from those used for comparison, are related to a localised ease of access to specific centres of activity according to the centralised development of the city’s job market along the mass transit lines. In terms of housing costs, we developed a set of difference-in-difference models that considered rent, transport, and public utilities costs; however, none of them have allowed us to conclude that there was a statistically valid relationship between the Metrocable and the changes in costs between the two analysed populations.  相似文献   

12.
Every day, a significant part of the population in large cities suffers transport congestion. One effect of this is a change in the spatial distribution of accessibility, which may lead to people or businesses finding themselves temporally in areas where accessibility values are lower than either desired or required. This paper studies changes in automobile accessibility over the course of the day, as caused by congestion of the road network in eight metropolitan areas of the European Union: London, Paris, Madrid, Berlin, Barcelona, Rome, Hamburg and Milan. The study was carried out using millions of data points on real speeds on segments of the road networks gathered over the course of two years from TomTom® devices, which provided for the incorporation of a dynamic perspective of accessibility. In each of the areas studied, the different impacts of congestion on automobile accessibility can be observed from differences in the distribution of opportunities and the provision of infrastructures, as well as from differences in culture and customs. Despite these differences, all cities experience two peaks with a lower value during the morning and afternoon. However, results show differences in the intensity and form of the effects of congestion on accessibility in these metropolitan areas. London, Paris and Rome are the cities where congestion has the greatest impact on automobile accessibility, while the Spanish cities are hardly affected by it.  相似文献   

13.
Improving job accessibility based on transport connectivity helps to address equity issues. Spatial autocorrelation (SA) is also a focus of interest in transportation planning, but has been neglected in analyzing job accessibility in metropolitan areas. In this study, GIS-based job accessibilities by walking, transit, and car are computed for the metropolitan area of Columbus, Ohio, and three transport-based spatial autoregressive (SAR) models are estimated to account for the SA of job accessibility among neighboring block groups, while controlling for built-environment and socioeconomic factors. SA intensities and extents are compared in order to better understand local spatial clusters of job accessibility across the region. Direct and indirect spillover effects due to an investment change in transportation facilities are estimated and provide important transportation planning information. The results also show that walking-accessed jobs are primarily related to physical settings (e.g., land uses) at the local level. Locations with a higher share of zero-vehicle housing units have better job accessibility by transit. There is a spatial mismatch between Asian population clusters and transit-accessed jobs, possibly because of the car-oriented residential clusters around Honda of America Manufacturing in suburban areas. More importantly, locations with a higher share of single-parent households are at a disadvantage in overall job accessibility. Due to its complex transportation needs, a society friendly to single parents should spatially integrate accessible jobs with other needed activities via land-use and transportation planning. Alternatively, car-ownership programs and non-spatial social supports also might be effective to help secure job opportunities and perform daily life activities.  相似文献   

14.
The achievement of good spatial accessibility and equity in the distribution of urban services is one of the supreme goals for urban planners. With Scottish Government backing, the City of Edinburgh Council (CEC) has started to construct a tram network to cater for the future needs of Scotland’s capital city by providing an integrated transport solution using trams and buses. Spatial Network Analysis of Public Transport Accessibility (SNAPTA) which is a GIS-based accessibility model has been developed to measure the accessibility by public transport to different urban services and activities. The model responds to several limitations in other existing accessibility models in planning practice. It offers an alternative and practical tool to help planners and decision makers in examining the strengths and weaknesses of land use – transport integration. SNAPTA has been applied to a pilot study in Edinburgh city to identify the contribution of the infrastructure improvements of the tram system and Edinburgh South Suburban Railway (ESSR) to improved accessibility by public transport to six types of activity opportunities. This paper outlines the concept and methodology of the SNAPTA model, and presents the findings related to this pilot study with a focus on changes in potential accessibility to jobs between four different public transport network scenarios. The accessibility values so obtained help to identify the gaps in the coverage of the public transport network and the efficiency in the spatial distribution of urban services and activities. The findings focus on whether the planned transport infrastructures for Edinburgh will lead to better accessibility and reduced inequity (in terms of accessibility) across the city.  相似文献   

15.
The relationship between high-speed railway (HSR) construction and economic development has become a significant concern in recent decades. This study uses the spatiotemporal panel data of China's HSR construction and economic development from 2008 to 2018 as bases to discuss the spatial–temporal heterogeneity of the relationship between HSR and the urban economy. Firstly, this research measures the accessibility of different dimensions (i.e. location accessibility, potential accessibility and daily accessibility), and assesses the regional disparity of HSR accessibility and urban GDP using the Gini index. Secondly, the direct and indirect effects of HSR on economic development are analyzed from the global perspective by using the spatial Durbin model. Lastly, the geographically and temporally weighted regression model is applied to assess the spatial–temporal heterogeneity of the correlation between HSR and economic development from a local perspective. The conclusions are as follows. (1) The construction of HSR might reduce the regional disparity of daily accessibility, but expand the disparity of potential accessibility and location accessibility. (2) From a global perspective, HSR has a significant positive impact on urban economic development, but this impact was mainly produced by the spillover effect and not the direct effect. Specifically, the smaller the spatial–temporal distance between cities, the higher the level of regional integration and the better the economic development of cities. (3) The HSR impact on urban economic growth has a periodic feature. The stimulation of large-scale railway construction will expand the economic effect of HSR, although network improvement will gradually converge the corresponding impact. (4) From a local perspective, the HSR impact on economic development has significant spatial heterogeneity. Although HSR has a certain inhibitory effect on the economic development of Eastern China, it has a positive impact on the economic growth of the western region.  相似文献   

16.
Job accessibility and environmental quality are rarely equally distributed in spatial and/or social dimensions within metropolitan regions. Availability of these affects the quality of residential locations, and can be expected to be capitalised into house prices. For prospective house owners, their options will be limited to sub housing markets within certain price bands depending on their available housing budgets. Availability and marginal prices of job accessibility and environmental quality, as well as trade-offs between them, might be different between these submarkets. Using Greater London as the case metropolitan region, this study explored such differences, to shed light on the role of housing market in equity and/or inequity in job accessibility, environmental quality and their interactions. Results of this study show that lower-price submarkets have advantages in job accessibility in terms of marginal price, but are disadvantaged in terms of availability. Differences are more mixed in marginal price and availability between the submarkets for environmental quality. When balancing job accessibility and environmental quality within constrained housing budgets, households in lower-price submarkets would find it relatively easier to gain job accessibility with less sacrifice on environmental quality as compared to those searching in higher-price submarkets, but hard to reach the higher levels of job accessibility that are mainly reserved for the higher-price submarkets.  相似文献   

17.
This study explores the relationship between urban form at the metropolitan and neighborhood scales and the percentages of four individual modes to commute. It then looks at the combined effects of urban forms at the metropolitan scale in metropolitan areas in the continental United States using multi-level regression models with interactive terms between urban forms. This study contains the percentages for four commute modes: percentage of the vehicle (VT), public transit (PT), biking (BI), and walking (WK). As urban form factors, this study contains urban fragments, population density, job-resident balance (JRB), the percentage of green areas at the metropolitan scale, and distance to the nearest job center at the neighborhood scale. The results show that at the neighborhood scale, a farther distance from individual neighborhoods to the nearest job center is associated with higher VT, and lower PT, BI, and WK. At the metropolitan scale, urban form factors have a more significant association with the percentage of individual modes to commute in large MSAs compared with small MSAs in terms of population. Most urban form factors at the metropolitan scale are not independently associated with the use of commute modes, but their interactions are associated with the percentage of individual modes to commute. Particularly, the level of urban fragments and the percentage of green areas may transform the impact of high population density and JRB on the percentage of the individual modes to commute except for WK. This study provides planners and policymakers with important guidelines to establish combined urban form plans rather than single urban form oriented plans to reduce vehicle travel.  相似文献   

18.
In this paper, we analyze the impact of orbital motorways on intra-metropolitan accessibility, using as an example the Madrid M-40 orbital motorway. The maps of changes in accessibility show that, as one might expect, the nodes situated near the M-40 are those that most benefit from the new infrastructure and that the further their distance from the M-40, the weaker the changes, although the gradient is much steeper towards the city centre than towards the exterior. All the indicators used point to the fact that the new orbital motorway has brought about relevant changes, but the intensity with which such changes are registered depends on the variable used as a mass (changes are higher in accessibility to population indicators than in accessibility to employment indicators), and on the type of operationalization adopted (the most complex ones are those which least noticeably reflect the effect of the new orbital motorway). It has been verified, in the case of the Madrid M-40, that orbital motorways do not necessarily lead to an increase in the equality of intra-metropolitan accessibility, for this will depend on their location within the metropolitan area: the further out they are, the greater equality they bring, even though they attract less traffic.  相似文献   

19.
A new high-speed railway line (HSR) connects seven metropolitan areas in Taiwan. From Tainan, it is possible to reach Kaohsiung, Chiayi and Taichung in less than one hour, implying an enlarged spatial range of feasible commuting opportunities. The implicit price of HSR accessibility is estimated using hedonic price functions for the residential property market. The results of pre-specified and Box-Cox hedonic price functions are compared. The estimated functions show that HSR accessibility has at most a minor effect on house prices. High ticket prices and entrenched residential location patterns prevent otherwise feasible daily commuting opportunities between Tainan and other cities.  相似文献   

20.
Like other major metropolitan areas, the urban complex that extends from Los Angeles to Orange County faces numerous transportation challenges. Daily traffic congestion, reduced productivity and loss of income, air pollution, environmental degradation and significant energy consumption are only a few outcomes of the millions of miles travelled every day on the region’s highways and streets. An important response to this significant urban challenge has been the desire for further expansion of an efficient public transportation network and increasing densities in particular areas within the larger metropolitan region. In this paper, we estimate the current energy consumption patterns in various communities, arguing that policy attempts to achieve higher density and better jobs-housing balance should fully consider the social geography of our metropolitan areas and their close relationship with energy consumption patterns.  相似文献   

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