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1.
The phenomenon of urban sprawl has strong impacts on transport performance and accessibility and causes an increase of air pollution. Effective control of urban sprawl requires an integrated approach comprising urban transport and land-use planning. Current research is insufficient to demonstrate the effects of urban sprawl on travel behavior and air pollution emission. The present paper examines the potential of an integrated approach on space–transport development strategies with the aim of increasing accessibility and reducing air pollution. A combination of space and transport strategies has been simulated for the rapidly expanding city of Surabaya. A comparative analysis of the impact of those cases indicates the promising potential alternatives to minimize the phenomenon. The transport options considered are combinations of Public Transport (PT), comprising Mass Rapid Transit (MRT), Light Rapid Transit (LRT), and Bus Rapid Transit (BRT). The options for urban structure include a compact zone development for the city, as formulated by the city planning agency, and a polycentric city set-up based on a job-housing balance aimed at minimizing the house-job distance. The results indicate that the polycentric city structure has the potential to make public transport work successfully for the city of Surabaya. This city structure creates a trip demand pattern which matches citizens’ PT preferences. Compared to the current situation, the combination of such a city structure with an expansion of PT systems would lead to a considerable improvement of transport performance, i.e. a PT mode share, a mean commute distance, and a significant reduction in emissions.  相似文献   

2.
The cost of nation wide travel surveys is high. Hence in many developing countries, planners have found it difficult to develop intercity transportation plans due to the non availability of origin‐destination trip matrices. This paper will describe a method for the intercity auto travel estimation for Sri Lanka with link traffic volume data.

The paper outlines the rationale of selecting the district capitals of Sri Lanka as its “cities,” the methodology for selecting the intercity road network, determination of link travel times from express bus schedules and the location of link volume counting positions.

Initially, the total auto travel demand model is formulated with various trip purpose sub‐models. This model is finally modified to a simple demand model with district urban population and travel times between city pairs as the exogenous variables, to overcome statistical estimation difficulties. The final demand model has statistics within the acceptable regions.

The advantages of a simple model are discussed and possible extensions are proposed.  相似文献   

3.
When public transport is the main means of travel in urban areas, management and planning are easy and the main objective can be to minimise costs for the demand available, i.e. maximise profit. However when public transport faces competition from other modes of transport, and activities can be undertaken in a variety of locations, then the management and planning of public transport services is considerably more difficult.This paper examines a methodology for representing consumer behaviour when faced with alternative travel decisions, in order to identify the demand for public transport and to help operators adjust services and prices to maximise demand, when considering people's disposable income, the alternative modes and activity locations available. From this it is possible to devise criteria for maximising consumer surplus in a city, taking into account social benefits.  相似文献   

4.
In many cities of the world, road space is increasingly contested. Growing vehicle numbers, traffic calming and the development of new infrastructure for more sustainable transport modes such as bicycles have all contributed to pressure on available space and conflicts over the allocation of space. This paper provides the first assessment of urban transport infrastructure space distribution, distinguishing motorized individual transport, public transport, cycling and walking. To calculate area allocation, an assessment methodology was developed using high-resolution digital satellite images in combination with a geographical information system to derive area measurements. This methodology was applied to four distinctly different city quarters in Freiburg, Germany. Results indicate that space is unevenly distributed, with motorized individual transport being the favoured transport mode. Findings also show that if trip number to space allocation ratios are calculated, one of the most sustainable transport modes, the bicycle, is the most disadvantaged. This suggests that area allocation deserves greater attention in the planning and implementation of more sustainable urban transport designs.  相似文献   

5.
This study explores the optimal investment in the length of an expanded section of road to mitigate the congestion on a transportation corridor. It is assumed that one end of the road is in the central business district (CBD) and that the households are uniformly distributed along the road. Each individual makes trips from his/her residence to the CBD. Trip demand is elastic and depends on the cost of the trip (including congestion costs). During the first stage, the government determines the length of the expanded section given the width of that section. In the second stage, road users determine their trip demands by taking into consideration the trip cost function. In the process of solving this problem, the equilibrium traffic volume is first solved using differential equations. The optimal length of the expanded section is then solved by maximizing the social welfare. The analysis is then applied to the case of the Tucheng city – Banciao city – Taipei CBD corridor in the Taipei metropolitan area. The scheme of road expansion without tolling performs closely to the first-best scheme for the case of a high potential demand. This study’s approach can serve as valuable reference for city planners engaged in road planning in a transportation corridor between the CBD and satellite cities in a metropolitan area.  相似文献   

6.
The issue of a peak in world oil supply has become a mainstream concern over the past several years. The petroleum geology models of post-peak oil production indicate supply declines from 1.5% to 6% per year. Travel requires fuel energy, but current transportation planning models do not include the impacts of constrained fuel supply on private travel demand. This research presents a method to assess the risk to activities due to a constrained fuel supply relative to projected unconstrained travel demand. The method assesses the probability of different levels of fuel supply over a given planning horizon, then calculates impact due to the energy supply not meeting the planning expectations. A new travel demand metric which characterizes trips as essential, necessary, and optional to wellbeing is used in the calculation. A case study explores four different urban forms developed from different future growth options for the urban development strategy of Christchurch, New Zealand to 2041. Probable fuel supply availability was calculated, and the risk to transport activities in the 2041 transport model was assessed. The results showed all the urban forms had significantly reduced trip numbers and lower energy mode distributions from the current planning projections, but the risk to activities differed among the planning options. Density is clearly one of the mitigating factors, but density alone does not provide a solution to reduced energy demand. The method clearly shows how risk to participation in activities is lower for an urban form which has a high degree of human powered and public transport access to multiple options between residential and commercial/industrial/service destinations. This analysis has led to new thinking about adaptation and reorganization of urban forms as a strategy for energy demand reduction rather than just densification.  相似文献   

7.
Ad hoc shared ride trip planning (SRTP) utilizes mobile devices, geo-sensors and wireless networks to match on-the-fly individual travel demand with transport supply. It represents one of many alternatives to single occupancy vehicle use. This paper outlines a SRTP approach via a two-phase algorithm based on user preferences in a time-dependent routing. Whereas current algorithms use minimization of travel time as the only optimization criterion in trip planning, in the framework presented here, the user can specify multiple trip preferences including travel time, walking time, number of transfers between cars and trip length. Various scenarios are simulated in the city of Tehran (Iran) to demonstrate how preference settings affect the routes of ad hoc shared journeys.  相似文献   

8.
This paper examines all the disparate technologies and techniques capable of smoothing the integration of public transport modes and services at both the urban and interurban scale. The paper focuses on the application of information technology and telematics solutions which have been designed to create as seamless a journey as possible from the point of view of the transport system user. The scope of the paper is therefore deliberately wide‐ranging and includes an examination of measures as apparently unconnected as smartcard ticketing, bus priority systems, automatic vehicle locationing, trip planning and on‐board information systems as well as new public transport services offering demand responsive travel and integration with taxi services. The paper intends to show how such technological solutions can be used to increase the attractiveness and competitiveness of fixed public transport networks in comparison to the door‐to‐door flexibility of the private car.  相似文献   

9.
Extensive work exists on regular rail network planning. However, few studies exist on the planning and design of ring-radial rail transit systems. With more ring transit lines being planned and built in Asia, Europe and the America's, a detailed study on ring transit lines is timely. An analytical model to find the optimal number of radial lines in a city for any demand distribution is first introduced. Secondly, passenger route choice for different rail networks is analyzed, for a many-to-many Origin-Destination (OD) demand distribution, based on a total travel time cost per passenger basis. The routes considered are: (1) radial lines only; (2) ring line only or radial lines and ring line combined; or (3) direct access to a destination without using the rail system. Mathematica and Matlab are used to code the route choice model. A cost-benefit optimization model to identify the feasibility and optimality of a ring line is proposed. Unlike simulations and agent-based models, this model is shown to be easily transferable to many ring-radial transit networks. The City of Calgary is used as an example to illustrate the applicability of each model. The existing urban rail network and trip distribution are major influencing factors in judging the feasibility and optimal location of the ring line. This study shows the potential net benefit of introducing a ring line by assessing changes in passengers’ costs. The changes in passenger cost parameters, such as ride cost and access cost, are shown to greatly influence the feasibility of a ring line.  相似文献   

10.
Charging infrastructure requirements are being largely debated in the context of urban energy planning for transport electrification. As electric vehicles are gaining momentum, the issue of locating and securing the availability, efficiency and effectiveness of charging infrastructure becomes a complex question that needs to be addressed. This paper presents the structure and application of a model developed for optimizing the distribution of charging infrastructure for electric buses in the urban context, and tests the model for the bus network of Stockholm. The major public bus transport hubs connecting to the train and subway system show the highest concentration of locations chosen by the model for charging station installation. The costs estimated are within an expected range when comparing to the annual bus public transport costs in Stockholm. The model could be adapted for various urban contexts to promptly assist in the transition to fossil-free bus transport. The total costs for the operation of a partially electrified bus system in both optimization cases considered (cost and energy) differ only marginally from the costs for a 100% biodiesel system. This indicates that lower fuel costs for electric buses can balance the high investment costs incurred in building charging infrastructure, while achieving a reduction of up to 51% in emissions and up to 34% in energy use in the bus fleet.  相似文献   

11.
12.
This paper develops a procedure for travel demand estimation via the Saaty method of Analytic Hierarchy. A stratification of the travel demand by trip-making and trip attributes has been represented more inclusively in a hierarchy system. Various elements and dimensions of the hierarchy have been hypothesized as different levels of decisions made by trip-makers. The elements contained in a set of specified matrices of travel attributes have been weighed utilizing a ratio scale, in a process of mapping transportation systems (modal) attributes with the characteristic trip-making behavior in a hierarchical demand structure. The principal output of this procedure is an estimate of the trip distribution by mode, or modal split. The estimate closely approximates the observed modal split pattern for the inter city travel problem simulated. This procedure is proposed for travel demand forecasting and planning.  相似文献   

13.
This paper provides an overview of the urban freight process, in the context of the supply and demand aspects of freight. A framework for analysis is developed, and within that framework, particular aspects of the urban freight process are described. Issues of concern from a public policy viewpoint are highlighted.

Seven main instruments related to public policy are introduced and their application described — taxes and subsidies, regulations, investment, operational instruments, planning, public ownership and research.

It is concluded that the importance of urban freight to the community and its relevance to urban transport justifies a higher level of attention in transport planning and policy formulation, and that there are a wide range of policy instruments available to enable this to be done. The objective of such planning and policy making needs to be specified in each specific context.  相似文献   

14.
This paper presents exploratory and statistical analyses of the activity–travel behaviour of non-workers in Bangalore city in India. The study summarises the socio-demographic characteristics as well as the activity–travel behaviour of non-workers using a primary activity–travel survey data collected by the authors. Where possible, the research also compares the analysis findings with the case studies on activity–travel behaviour of non-workers, carried out in developed and developing countries. This gives an opportunity to understand the differences/similarities in the activity–travel behaviour of non-workers across diverse socio-cultural settings. The preliminary exploratory analysis shed light on the differences in activity participation, trip chaining, time-of-day preference for trip departure, and mode use behaviour of non-workers in Bangalore city. Statistical models were developed for investigating the effects of individual and household socio-demographics, land use parameters, and travel context attributes on activity participation, trip chaining, time-of-day choice, and mode choice decisions of non-workers. A few important results of the analysis are the influence of viewing television at home on out-of-home activity participation and trip-chaining behaviour, and the impact of in-home maintenance activity duration on time-of-day choice. Further, based on the findings of the initial analyses, an attempt has been made in this study to develop an integrated model that links time allocation, time-of-day choice, and trip chaining behaviour of non-workers. The study also discusses the implications of the research findings for transportation planning and policy for Bangalore city.  相似文献   

15.
The distribution of freight is a major contributor to the levels of traffic congestion in cities. However it is much neglected in the research and planning activities of government, where the focus is disproportionately on passenger vehicle movements. Despite the recent recognition of the contribution of freight transportation to the performance of urban areas under the rubric of city logistics, we see a void in the study of how the stakeholders in the supply chain might cooperate through participation in distribution networks, to reduce the costs associated with traffic congestion. Given that transport costs are typically over 45 of all distribution costs, with congestion a major contributor in the urban setting, the importance of establishing ways in which supply chain partnerships might cooperate to reduce levels of freight vehicle movements has much merit. This paper sets out a framework to investigate how agents in a retail supply chain might interact more effectively to reduce the costs of urban freight distribution. We propose an interactive agency choice method as a way of formalising a framework for studying the preferences of participants in the supply chain to support specific policy initiatives. Such a framework is a powerful way of investigating the behavioural response of each agent to many policies, including congestion pricing, as a way of improving the efficient flow of traffic in cities.  相似文献   

16.
Studies on cities in Europe and the United States have demonstrated that travel behaviour is influenced by urban form. Based on these findings policies steering the shape of cities have been proposed to reduce urban transport emissions and limit congestion. Such policies can also be relevant for the rapidly growing and motorising Chinese cities. Yet, empirical evidence on the relationships between urban form and car usage is scarce for the specific Chinese context that is characterised by high densities, fast development and strong government steering. Using novel crowd-sourced datasets we study the impact of several urban form variables (city size, urban density, land-use mix, polycentricity and spatial clustering) on the cost of commuting expressed in time and distance. The results show that city size and spatial clustering are important determinants of commuting: large cities without clear clusters of businesses and other facilities have longer average commuting times and distances. Increased prosperity also adds to longer and lengthier commutes. Spatial planning measures that maintain or reinforce high-density clusters can help limiting commuting distance and time. Current sprawled urban development may have long-term, negative consequences for the accessibility and liveability of Chinese cities and could hamper their economic potential.  相似文献   

17.
Rising population, income and urbanization are increasing urban passenger transport demand in India. Energy and emissions intensities associated with conventional transport are no longer sustainable vis-a-vis energy security, air quality and climate change. Cities are seeking transport roadmaps that jointly mitigate these risks. Roadmaps vary across cities, but approach to delineate actions is common: (i) ‘representative vision’ that articulates long-term goals, (ii) methods for comparative scenarios assessment, and (iii) quantification of co-benefits to prioritize actions. This paper illustrates application of quantitative modeling to assess development and environmental co-benefits for Ahmedabad city. The paper constructs two transport scenarios spanning till 2035. The bifurcating themes are: (i) Business-as-Usual (BAU) and Low Carbon Scenario (LCS). The quantitative assessment using Extended Snapshot (ExSS) Model shows that transport activity shall result in four-fold increase in energy demand under BAU from 2010 to 2035. Three key contributors to CO2 mitigation under LCS in merit order are: (i) fuel switch, including decarbonized electricity, (ii) modal shift, and (iii) substitution of travel demand. Scenarios analysis shows that LCS improves energy security by reducing oil demand and also delivers air quality co-benefits – reducing 74% NOx and 83% PM2.5 from the passenger transport sector compared to BAU in 2035. Finally, the paper argues that cities in developing countries can leverage carbon finance to develop sustainable and low carbon mobility plans that prevent adverse infrastructure and behavioral lock-ins and prompt low carbon development.  相似文献   

18.
Many problems in transport planning and management tasks require an origindestination (O-D) matrix to represent the travel pattern. However, O-D matrices obtained through a large scale survey such as home or roadside interviews, tend to be costly, labour intensive and time disruptive to trip makers. Therefore, the use of low cost and easily available data is particularly attractive.The need of low-cost methods to estimate current and future O-D matrices is even more valuable in developing countries because of the rapid changes in population, economic activity and land use. Models of transport demand have been used for many years to synthesize O-D matrices in study areas. A typical example of this is the gravity model; its functional form, plus the appropriate values for the parameters involved, is employed to produce acceptable matrices representing trip making behaviour for many trip purposes and time periods.The work reported in this paper has combined the advantages of acceptable travel demand models with the low cost and availability of traffic counts. Three types of demand models have been used: gravity (GR), opportunity (OP) and gravity-opportunity (GO) models. Three estimation methods have been developed to calibrate these models from traffic counts, namely: non-linear-least-squares (NLLS), weighted-non-linear-least-squares (WNLLS) and maximumlikelihood (ML).The 1978 Ripon (urban vehicle movement) survey was used to test these methods. They were found to perform satisfactorily since each calibrated model reproduced the observed O-D matrix fairly closely. The tests were carried out using two assignment techniques, all-or-nothing and the stochastic method due to Burrell, in determining the routes taken through the network.requests for offprints  相似文献   

19.
This paper is at the conjunction of arguments for gender equity in transport services on one hand and need to move towards low carbon transport on the other in a developing country city. The case study city, Rajkot, a mid-sized Indian city with mixed land use and limited public transport at the time of this study, has short trip lengths and low trip rates. But, even in this city there is gender disparity in travel pattern. Thus, trip rates and trip lengths of women in the city in each of the income group are lower than that of their male counter parts. With the increase in income, both, the trip rates and lengths increase, but, the increase is higher for men than for women. While the large proportions of women in each income group walk, that among the lowest income group walking is the predominant mode, as they are ‘no-choice’ or ‘forced’ walkers. With the increase in household income, women tend to shift to para-transit and men to personal motorized transport. If sustainability arguments or climate policies are to target retaining the current low ecological footprint of the women as one of the strategies, it needs to cater to expansion of their mobility while improving infrastructure to support the same.  相似文献   

20.
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