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1.
Abstract

In comparison to personal travel, freight movements within large metropolitan areas are much less studied. Most conventional transportation models and planning analysis that disregarded freight flows have been criticized on the plausibility of their results and conclusions. To alleviate these problems, this study proposes a non-survey based approach to assemble and process freight data in a systematic way. A freight origin–destination (OD) matrix of freight flows can be developed using secondary data sources. The estimated freight flows can be loaded together with conventional passenger flows onto the regional highway network of a large metropolitan area. As a case study, this non-survey based approach was applied to build a freight OD and study the traffic flows in Los Angeles. It concluded that this approach can be used to analyze urban freight movement in a low-cost way in which planning agencies can overcome the common omission of freight flow information in their transportation plans.  相似文献   

2.
Abstract

An area pricing scheme for Jakarta, Indonesia, is currently under review as a transportation control measure along with the operation of new bus rapid transit (BRT) system. While this scheme may be effective for congestion reduction in the central business district (CBD), provision of alternative means of transportation for auto users that are ‘pushed-out’ is of great importance to obtain public acceptance. Hence, it is necessary to simulate simultaneously the area pricing scheme and the BRT development which may serve as an alternative for assumed ‘pushed-out’ auto users. Utilizing data from an opinion survey, this paper studies how BRT and auto ridership are likely to vary as a function of traveler and system attributes. Additionally, the study attempts to evaluate the way this new travel mode is distinguished from other existing conventional transportation alternatives in Jakarta. The survey data contains socioeconomic information of over 1000 respondents as well as details of to-work/school trips to the CBD including mode, travel cost, time, etc. Respondents were asked about their willingness to shift from their current mode to BRT to make the same travel for different BRT fare levels. Modeling efforts suggest that a mixed logit model performs better in explaining choice behavior. Therefore, this model was used for policy simulation. The simulation results brought about many implications as to the tested policies. While the developed models may be applied only to future BRT corridors in which the survey was conducted, they capture the key variables that are significant in explaining mode choice behavior and present great potential for practical use in policy simulation and analysis in a large metropolitan area of the developing world.  相似文献   

3.
This paper proposes different policy scenarios to cut CO2 emissions caused by the urban mobility of passengers. More precisely, we compare the effects of the ‘direct tool’ of carbon tax, to a combination of ‘indirect tools’ – not originally aimed at reducing CO2 (i.e. congestion charging, parking charges and a reduction in public transport travel time) in terms of CO2 impacts through a change in the modal split. In our model, modal choices depend on individual characteristics, trip features (including the effects of policy tools), and land use at origin and destination zones. Personal “CO2 emissions budgets” resulting from the trips observed in the metropolitan area of Lille (France) in 2006 are calculated and compared to the situation related to the different policy scenarios. We find that an increase of 50% in parking charges combined with a cordon toll of €1.20 and a 10% travel time decrease in public transport services (made after recycling toll-revenues) is the winning scenario. The combined effects of all the policy scenarios are superior to their separate effects.  相似文献   

4.
Abstract

Middle‐class expansion and new consumption patterns have increasingly become an important focus of studies of the development and change in newly industrialized and middle‐income‐developing East and South East Asian countries. However, there is still a dearth of studies in the literature particularly focusing on middle‐class travel patterns, predispositions and transport policy preferences. Nor have the implications of these factors on current transport and land development policy been examined. The present exploratory study addresses this gap by examining three cases in Bangkok, Thailand, which in recent decades witnessed dramatic middle‐class expansion, an increase in private motor vehicle population, and spatial diffusion of middle‐class residences into lower‐density zones in the suburbs. By mainly employing a survey method of data‐gathering and quantitative research analysis, the paper discusses the following findings: (1) that middle‐class travel behaviour is characterized by a high dependence on private motor vehicle travel and ‘inward commuting’; (2) that middle‐class preferences for transport mode and attitudes about remedial policy options are generally protective of their members’ car‐dependence and ownership; and (3) that present policy measures of the Thai government on Bangkok transport perfectly fit and support exclusively middle‐ and upper‐class predispositions and stakes in mobility. These findings in a developing country city basically follow a similar profile to be found in middle‐class‐dominant transport patterns and urban form in a number of North American cities. This paper further argues that in a developing country city such as Bangkok, where marked social differentiation and the combined population of poor and low‐income classes still comprise almost half of the urban social landscape despite an expanding middle‐class, an adequate and good public transport system that also meets the former’s need for efficient mobility is an imperative.  相似文献   

5.
This paper presents a system dynamics approach to simultaneous land use/transportation system performance modeling. A model is designed based on the causality functions and feedback loop structure between a large number of physical, socioeconomic, and policy variables. The model system consists of 7 sub‐models: population, migration of population, household, job growth‐employment‐land availability, housing development, travel demand, and traffic congestion level. The model is formulated in DYNAMO simulation language, and tested on a data set from Montgomery County, MD. In Part I: Methodology, the overall approach and the structure of the model system is discussed and the causal‐loop diagrams and major equations are presented. In Part II: Application, the model is calibrated and tested with data from Montgomery County, MD. Least square method and overall system behavior are used to estimate the model parameters. The model is fitted with the 1970–80 data and validated with the 1980–1990 data. Robustness and sensitivities with respect to input parameters such as birth rate or regional economy growth are analyzed. The model performance as a policy analysis tool is also examined by predicting the year by year impacts of highway capacity expansion on land use and transportation system performance. While this is a first attempt in using dynamic system simulation modeling in simultaneous treatment of land use and transportation system interactions, and model development and application are limited to some extent due to data availability, the results clearly indicate that the proposed method is a promising approach in dealing with complex urban land use/transportation modeling  相似文献   

6.
The need for sustainable development is increasing as the industrial and service activities keep putting such a strain on the natural functions of the Earth, thus the ability of the planet’s to sustain future generations. Since most of the industrial and service activities are provided via transportation, it is one of the most crucial elements of sustainable development. In this paper, US highway system sustainability problem is studied. System dynamics modeling approach is employed due to the causal relationships and feedback loops that are observed in the problem structure. The reference mode is considered as the increasing CO2 emission trend. The objective is to meet the Liberman and Warner Climate Act’s targets by 2050. Three potential strategies for policy making are tested with the developed dynamic simulation: fuel efficiency, public transportation and electric vehicle usage. The results indicate that hybrid implementation of individual policies has a crucial impact on the success of policy making.  相似文献   

7.
This paper presents a system dynamics approach to simultaneous land use/transportation system performance modeling. A model is designed based on the causality functions and feedback loop structure between a large number of physical, socioeconomic, and policy variables. The model consists of 7 sub‐models: population, migration of population, household, job growth‐employment‐land availability, housing development, travel demand, and traffic congestion level. The model is formulated in DYNAMO simulation language, and tested on a data set from Montgomery County, MD. In Part I: Methodology, the overall approach and the structure of the model system is discussed and the causal‐loop diagrams and major equations are presented. In Part II: Application, the model is calibrated and tested with data from Montgomery County, MD. Least square method and overall system behavior are used to estimate the model parameters. The model is fitted with the 1970–80 data and validated with the 1980–1990 data. Robustness and sensitivities with respect to input parameters such as birth rate or regional economy growth are analyzed. The model performance as a policy analysis tool is examined by predicting the year by year impacts of highway capacity expansion on land use and transportation system performance. While this is a first attempt in using dynamic system simulation modeling in simultaneous treatment of land use and transportation system interactions, and model development and application are limited due to data availability, the results indicate that the proposed method is a promising approach in dealing with complex urban land use/transportation modeling.  相似文献   

8.

One perspective on the allocation of transport investments by public authorities is offered by the so‐called ‘pork barrel’ model, whereby politicians and political parties allocate public investment spatially in such a way as to gain electoral support from localities so benefited. The paper introduces this model and discusses its attractions and problems in the case of the transport sector. A review of the modest number of published examples of this approach is offered before a detailed case study considers the case of railway investment in Nelson, New Zealand.  相似文献   

9.

Foreign consultants still provide much of the analytical expertise for transport planning studies conducted in the Gulf States and other rapidly developing countries. Most of the systems analysis techniques used are adaptations of those developed for western urban areas. The populations of the Gulf States are unique in that they contain very large populations of foreign workers who have very different social and economic characteristics from the national populations. This paper describes these differences and shows how they have influenced the spatial evolution of the Kuwait metropolitan area and the associated transport demands. The paper also describes the analytical tools that are most appropriate for capturing the transport behaviour of residents of the Kuwait metropolitan area.  相似文献   

10.

Particular safety problems relate to traffic on local streets. Local Area Traffic Management (LATM) schemes are often implemented with the objective of counteracting these safety problems. One analytical difficulty in appraising the effectiveness of LATM in dealing with safety problems has been the ‘footloose’ nature of accident locations in a local street network. Seldom are there distinct ‘blackspot’ locations. An area‐wide approach is needed and the interaction between the system and arterial road network must be considered. The paper describes the development of a Safety Evaluation Method for Local Area Traffic Management (termed SELATM). It is a GIS‐based program for analysing accident patterns over time and the evaluation of the safety benefits of LATM schemes. The evaluation is perform at different network levels for various accident variables. The thrust of the program involved the integration of network data with data on accidents and the installed devices to generate summary accident statistics for the various network levels allowing for before and after comparison with a control area. This program as developed is applied to a LATM scheme at Enfield, a suburb in metropolitan Adelaide.  相似文献   

11.
ABSTRACT

This paper describes the development of a probabilistic formulation that provides global optimum selection and allocation of a fleet of buses in a private transportation system of an organization where a third party is hired to provide transportation for its employees and their dependents. In this private transportation system, a fleet of buses is to be selected and allocated to serve employees and their independents on different prescheduled trips along different routes from the organization’s headquarters and residential compound where round-trip times of scheduled trips are subject to uncertainty due to random delays. We propose a probabilistic approach based on 0-1 integer programming for the selection and allocation to determine the optimal number and size of buses assigned to a set of prescheduled trips in a particular time interval. Examples and a case study are presented to illustrate the applicability and suitability of the proposed approach.  相似文献   

12.
Abstract

Based on a review of available data from a database on large‐scale transport infrastructure projects, this paper investigates the hypothesis that traffic forecasts for road links in Europe are geographically biased with underestimated traffic volumes in metropolitan areas and overestimated traffic volumes in remote regions. The present data do not support this hypothesis. Since previous studies have shown a strong tendency to overestimated forecasts of the number of passengers on new rail projects, it could be speculated that road planners are more skilful and/or honest than rail planners. However, during the period when the investigated projects were planned (up to the late 1980s), there were hardly any strong incentives for road planners to make biased forecasts in order to place their projects in a more flattering light. Future research might uncover whether the change from the ‘predict and provide’ paradigm to ‘predict and prevent’ occurring in some European countries in the 1990s has influenced the accuracy of road traffic forecasts in metropolitan areas.  相似文献   

13.
Abstract

Enhancing the bus experience through improved information provision is a key element of UK Government transport policy. Real time passenger information (RTPI) is perceived to reassure waiting passengers, to benefit the bus operator through increased revenue and the local authority, by promoting social inclusion and achieving a modal shift. RTPI also provides an important tool for operators by allowing them to monitor services and refine their schedules.

The aim of this paper is to understand the reasons for implementing RTPI in the bus sector, and to determine the key issues impacting on the likely success of such a policy. A case study approach investigates the experiences of two provincial towns in the UK. The paper suggests that, whilst it is unclear whether RTPI has resulted in an increase in bus patronage, it is considered to be most effective when combined as part of a package of measures. It is intended that the findings from the two case studies will reveal lessons of relevance to authorities contemplating the introduction of RTPI.  相似文献   

14.
This paper provides a modeling framework based on the system dynamics approach by which policy makers can understand the dynamic and complex nature of traffic congestion within a transportation socioeconomic system representation of a metropolitan area. This framework offers policy makers an assessment platform that focuses on the short- and long-term system behaviors arising from an area-wide congestion pricing policy along with other congestion mitigation policies. Since only a few cities in the world have implemented congestion pricing and several are about to do so, a framework that helps policy makers to understand the impacts of congestion pricing is currently quite relevant. Within this framework, improved bus and metro capacities contribute to the supply dynamics which in turn affect the travel demand of individuals and their choice of different transportation modes. Work travel and social networking activities are assumed to generate additional travel demand dynamics that are affected by travelers’ perception of the level of service of the different transportation modes, their perception of the congestion level, and the associated traveling costs. It is assumed that the, population, tourism and employment growth are exogenous factors that affect demand. Furthermore, this paper builds on a previously formulated approach where fuzzy logic concepts are used to represent linguistic variables assumed to describe consumer perceptions about transportation conditions.  相似文献   

15.
Abstract

This paper presents the hypothesis that in order to create a safer road environment, there needs to be a change in the approach used by police services. A shift in methodology is required that moves away from punishment, such as issuing traffic tickets, and its attendant measures of success, total number of tickets issued or total amount of fines, to a safety-based methodology with its main emphasis on reducing collisions and their severity. This requires understanding the social context of driving and how dangerous driving is defined. This paper moves from these topics to describing deterrence theory which is the common philosophy underlying the criminal justice system today, including how the police handle traffic violations. A different approach is then presented which draws from these methods but changes the focus of police resource deployment.  相似文献   

16.
Abstract

This study was designed to present an online model which predicted travel times on an interurban two-lane two-way highway section on the basis of field measurements. The study included two parts: an evaluation of the performance of the model, and an examination of the possibility to improve the model in case of unsatisfactory performance. The model was based on MLP neural networks. The main results of the evaluation showed that the prediction model outperformed a non-predictive system. However, the model for one section had not performed as well during the trial period as was expected. This might be due to a slight change in the congestion phenomenon. After further development, the findings showed that the model could be improved considerably with new data. The main implication was that even a simple prediction model improves the quality of travel time information substantially, compared to estimates based directly on the latest measurements.  相似文献   

17.
The role of transport disadvantage in the social exclusion of low income and marginalised households and communities has received increasing academic and policy interest over the last 10 years or so. Against a backdrop of studies that have predominantly considered this issue within various national contexts, this paper offers a unique opportunity to compare different national context. The paper is informed by a commissioned study for the State of Victoria Department of Transport (Lucas, Study of transport exclusion in the state of Victoria: It doesn’t have to be this way, 2008), which wished to draw lessons from the United Kingdom in order to promote a similar policy agenda for the State. It is the authors’ contention that the issue of transport-related social exclusion is likely receive growing international policy recognition in the context of global recession, associated local job losses and reduced disposable incomes, as well as the ageing structure of most Western societies. The paper seeks to disseminate the important findings of our study about the potential for policy transfer to other national and local contexts to a wider academic, policy and practitioner audience.  相似文献   

18.
This paper is employing the well-known methodology of impact pathway approach to assess the external costs in human health from ship air pollution at port areas. The passenger port of Piraeus, Greece is the scenery of the study. Piraeus port is in the vicinity of the greater Athens metropolitan area where almost half of the country’s population lives. Hence, this port is the central hub of the Greek coastal passenger ship system which connects the islands of the Aegean Sea with land and is characterized by heavy ship traffic. The case study presented in this paper assesses the annual external cost in human health from air emissions produced by all passenger ships and cruise ships calling the port of Piraeus. Health cost from ships at port has been estimated at both local (Athens metropolitan area) and regional level (entire territory of Greece). Results show that higher costs occur at the local level. The dominant pollutants creating this cost are particulate matter (PM2.5, and PM10). Overall, the results indicate that the health impact of Piraeus’s passenger port emissions is not negligible; however the cost of PM10 is considerably lower than the corresponded cost deriving from the land based industries of the Athens regional area for which comparison has been available.  相似文献   

19.

After forty years of economic regulation, the U.S. interstate aviation industry was ‘deregulated’ in 1978. This paper offers an assessment of the reasons for this radical change in official federal policy and an evaluation of the longer term impact of the reforms. Further, it provides a number of observations regarding the universality of the experiences of the U.S.A. in the context of the gradual liberalization of aviation regulation in general and the ‘deregulation’ of European aviation in particular.  相似文献   

20.

Transport policy in Korea is driven by the need to cope with ever-worsening traffic conditions. The development of an intelligent transport systems (ITS) Master Plan for Korea is of particular interest and demonstrates the heavy reliance placed on ITS measures to facilitate both the management of congested (but expanding) highway networks and to encourage a shift to greater use of public transport. The paper highlights the major achievements of ITS in Korea by assessing the evidence provided by the widespread implementation of ITS technologies (such as the creation of 'showcase' demonstrations). Some observations from the implementation of ITS in (so-called) transitional economies are presented.  相似文献   

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