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1.
Abstract

An introduction to random-utility-based multiregional input–output models used for the purpose of spatial economic and transport interaction modelling is provided. The main methodological developments and important results of a dozen applications from the years 1996–2013 are described. This is followed by an outlook of potential future directions. Further research is mainly needed in five areas: (a) overall validation of the method, perhaps through back-casting applications on infrastructure plans with observed trade impacts; (b) extensions of trade coefficient models to add realism and improve accuracy; (c) the use of multi-scale modelling to capture interdependencies between geographical scales and to improve the representation of exports and imports; (d) improvements in the representation of price effects, as well as innovation and technological progress, by way of variable technical coefficients; and (e) a deeper investigation of the algorithm used to include elastic selling prices.  相似文献   

2.
The limited understanding of public–private partnerships (P3s) for transportation infrastructure finance has been generally attributed to a lack of data. The more fundamental question of how P3 data are utilized in the literature is more relevant and critical, but remains unclear. This study investigates this question by examining the linkages between research objectives and data characteristics through a meta-analysis of infrastructure P3 studies using multinomial regressions. It analyzes 95 empirical studies that adopt actual data, selected from a P3 research database that includes over 345 studies and are classified into five categories including performance, contract, risk, value for money, and institutional factors. Results show that the case studies are less frequently utilized to understand P3s' institutional issues compared to those that focus on P3s' performance or VFM. Survey data are more frequently used to study P3 contracts rather than issues related to P3 project risk. We highlight the need for policy-makers to require continuing disclosure of P3 performance for validating the effectiveness of the procurement model and to improve the practice.  相似文献   

3.
The two models FOTO (Forecasting of Traffic Objects) and ASDA (Automatische Staudynamikanalyse: Automatic Tracking of Moving Traffic Jams) for the automatic recognition and tracking of congested spatial–temporal traffic flow patterns on freeways are presented. The models are based on a spatial–temporal traffic phase classification made in the three-phase traffic theory by Kerner. In this traffic theory, in congested traffic two different phases are distinguished: “wide moving jam” and “synchronized flow”. The model FOTO is devoted to the identification of traffic phases and to the tracking of synchronized flow. The model ASDA is devoted to the tracking of the propagation of moving jams. The general approach and the different extensions of the models FOTO and ASDA are explained in detail. It is stressed that the models FOTO and ASDA perform without any validation of model parameters in different environmental and traffic conditions. Results of the online application of the models FOTO and ASDA at the TCC (Traffic Control Center) of Hessen near Frankfurt (Germany) are presented and evaluated.  相似文献   

4.
Since 2000 it has been formally required in the Netherlands to evaluate major infrastructure projects according to a standard manual. Here the focus is on its application to the Zuider Zee line, a possible rail link to run from the west to the north of the country, starting at Schiphol Airport and ending at the northern towns in the province of Groningen. We put a major emphasis on environmental impacts of the line, including the methods used to estimate impacts and the results. Ways to improve current practice are discussed. A major advantage has been that the environment has been put on the research and policy agenda at an early stage, although insights into the effects of rail infrastructure on the landscape and nature are limited.  相似文献   

5.
A procedure for the simultaneous estimation of an origin–destination (OD) matrix and link choice proportions from OD survey data and traffic counts for congested network is proposed in this paper. Recognizing that link choice proportions in a network change with traffic conditions, and that the dispersion parameter of the route choice model should be updated for a current data set, this procedure performs statistical estimation and traffic assignment alternately until convergence in order to obtain the best estimators for both the OD matrix and link choice proportions, which are consistent with the survey data and traffic counts.Results from a numerical study using a hypothetical network have shown that a model allowing θ to be estimated simultaneously with an OD matrix from the observed data performs better than the model with a fixed predetermined θ. The application of the proposed model to the Tuen Mun Corridor network in Hong Kong is also presented in this paper. A reasonable estimate of the dispersion parameter θ for this network is obtained.  相似文献   

6.
The paper sets in context some of the more recent work that has been conducted on public–private partnerships (PPPs) in the provision and operation of infrastructure. PPPs essentially involve a government or its agent signing an agreement with a private company or consortium to supply it with services with the private sector actor involved in major elements of designing, building, temporarily ‘owning’, and running the physical assets; basically they are long-term development and service contracts between government and a private partner. The paper outlines the development of economic thinking regarding the rationale behind PPPs, the extent to which unbundling is optimal and the forms that it may take, the nature of the contracts that are enacted and their renegotiation, the awarding of contracts, and matters of possible corruption. By way of focus, it also provides some indication of what empirical studies in the transportation have thrown up regarding the outcomes of PPPs.  相似文献   

7.
In this paper, we take an initial look at the spatial and temporal flexibility in the activity patterns of the so-called “baby-boomer” cohort (born 1947–1966) in comparison with younger and older adults. Using a unique longitudinal survey carried in Quebec City from 2002 to 2005, we explore activity patterns and trip rates over a seven-day observation period during the first wave, and take a first look at some aspects of their evolution over two subsequent waves at about one-year intervals. We model the propensity to undertake activities within selected conventional non-work classifications such as “shopping” and “leisure”, and also according to respondents’ own perceptions of the spatial and temporal flexibility of each out-of-home activity that they had executed. While we cannot strictly separate cohort effects from age-related effects, after controlling for gender and household structure, we infer that age and related lifestyle effects dominate in explaining these propensities. However, the boomers were the only age stratum to increase their total out-of-home activity participation over the course of the panel, an intriguing starting point for the future study of this cohort.
Martin Lee-GosselinEmail:

Luis F. Miranda-Moreno   has been recently appointed as Assistant Professor in the Department of Civil Engineering and Applied Mechanics at McGill University. His research focuses on travel behaviour, transportation safety and evaluation of sustainable transport strategies. Martin Lee-Gosselin   recently retired as Full Professor at the Graduate School of Planning and CRAD, Université Laval, Québec, and is Visiting Professor at Imperial College London. His research interests are transport and telecommunications behaviour, survey methods, energy efficiency and the impacts of transport on the environment and public health.  相似文献   

8.
Abstract

The motorcycle is a popular mode of transport in Malaysia and developing Asian countries, but its significant representation in the traffic mix results in high rates of motorcycle accidents. As a result, the Malaysian Government decided to segregate motorcycle traffic along its new federal roads as an engineering approach to reduce accidents. However, traffic engineers needed to know the maximum traffic a motorcycle lane could accommodate. Despite substantial literature related to speed–flow–density relationships and capacities of various transport facilities, there is a knowledge gap regarding motorcycle lanes. This paper establishes motorcycle speed–flow–density relationships and capacities of exclusive motorcycle lanes in Malaysia. Observations of motorcycle flows and speeds were conducted along existing and experimental motorcycle lanes. Motorcycle speed–density data were aggregated and plotted for two types of observable motorcycle riding behaviour patterns that were influenced by the widths of a motorcycle lane: the headway pattern (lane width ≤ 1.7 m) and the space pattern (lane width > 1.7 m). For both riding patterns, regression analysis of motorcycle speed–density data best fits the logarithmic model and consequently the motorcycle flow–density and speed–flow models are derived. Motorcycle lane capacities for headway and space riding patterns are estimated as 3300 mc/hr/lane and 2200 mc/hr/m, respectively.  相似文献   

9.
In many past studies dealing with traffic phenomena in merging or weaving sections, only the influence of through traffic on the behavior of a merging car is considered in the analysis. It is, however, often seen that a through car, which runs on the most outside lane, takes a cooperative motion for the merging car called “giving way” by moving to the adjacent lane. That is, both the merging car and the through car affect one another. Because their influence is not independent from one another, it should be jointly treated in the analysis as “interaction”. This behavior is typical in merging sections, and is a dominant factor forming the traffic phenomena in a section of this type. This study develops a game theoretical model to describe the traffic behavior of a pair of merging and through cars, while explicitly considering the interaction between them. Both the merging and through cars attempt to take the best actions for themselves by forecasting the other’s action, respectively. Such a behavior is modeled as a two-person non-zero-sum non-cooperative game. Through a case study with data analysis of videotaped observation, the proposed model can be used to obtain an understanding of traffic behavior at on-ramp merging sections. ©  相似文献   

10.
11.
Using Herfindahl–Hirschman Index and the Mobidrive and Thurgau six-week travel diary datasets this paper examines the degree of repetition of individuals’ choices of their daily activity–travel–location combinations. The results show that the repetitiveness of individual activity–travel–mode–location combinations is highly influenced by the individuals’ out-of-home commitments, the intra-household conditions and the availability and the accessibility of the activity locations. Different types of activity have different pattern of repetition. The level of repetition of individual’s daily activity–travel pattern is less correlated to travel mode choice, but more to the individuals’ commitments and obligations. The repetitiveness of mode choices is more related to the conditions or the accessibilities of the activity location, but not directly to the activity itself.  相似文献   

12.
This study analyzes the annual vacation destination choices and related time allocation patterns of American households. More specifically, an annual vacation destination choice and time allocation model is formulated to simultaneously predict the different vacation destinations that a household visits in a year, and the time (no. of days) it allocates to each of the visited destinations. The model takes the form of a multiple discrete–continuous extreme value (MDCEV) structure. Further, a variant of the MDCEV model is proposed to reduce the prediction of unrealistically small amounts of vacation time allocation to the chosen destinations. To do so, the continuously non-linear utility functional form in the MDCEV framework is replaced with a combination of a linear and non-linear form. The empirical analysis was performed using the 1995 American Travel Survey data, with the United States divided into 210 alternative destinations. The model estimation results provide several insights into the determinants of households’ vacation destination choice and time allocation patterns. Results suggest that travel times and travel costs to the destinations, and lodging costs, leisure activity opportunities (measured by employment in the leisure industry), length of coastline, and weather conditions at the destinations influence households’ destination choices for vacations. The annual vacation destination choice model developed in this study can be incorporated into a larger national travel modeling framework for predicting the national-level, origin–destination flows for vacation travel.  相似文献   

13.
Abstract

Although per‐capita car trip distance (measured in passenger‐km) and car driving distance (measured in vehicle‐km) in the UK have kept increasing, their growth rates slowed considerably in the 1990s when compared with the 1970s and 1980s. The paper investigates the main driving forces behind the changes in car trip and car driving distances, and it examines the determining factors for the slow down of growth in the 1990s on the basis of the analysis of data from the National Travel Survey (1975/76, 1989/91, 1992/94, 1995/97 and 1999/2001). In particular, it emphasizes the significance of changes in car ownership levels as a key driving force and attempts to separate this ‘car ownership effect’ from other effects. The log‐mean Divisia index decomposition method is applied to measure the relative contribution of each effect. Separate analyses are undertaken according to trip purpose. Other underlying causes, such as changes in fuel price and road capacity, are also examined.  相似文献   

14.
Intermodal freight transport has developed into a significant sector of the transport industry in its own right. This development has been followed by an increase in intermodal freight transportation research. We contend that a new transportation research application field is emerging; and that, while still in a pre-paradigmatic phase, it is now time to move on to a more mature independent research field. An independent research field can be justified because intermodal transport is a complex system that has characteristics which distinguishes it from other transport systems. We have reviewed 92 publications in order to identify the characteristics of the intermodal research community and scientific knowledge base. This paper will discuss aspects of this research, assessing the status quo and seeking directions for the future. To conclude, we will propose an intermodal research agenda which can direct the intermodal research field towards a period of “normal science”.  相似文献   

15.
Abstract

This paper presents a review of time-series analysis of road safety trends, aggregated at a national level, which has been performed in the period 2000–12 and applied to European national data sets covering long time periods. It provides a guideline and set of best practices in the area of time-series modelling and identifies the latest methods and applications of national road safety trend analysis in Europe. The paper begins with the methodological framework adopted for aggregate time-series modelling that will be considered, and then discusses a number of relevant applications to long-period data aggregated at the national level, whether for countries alone, or for groups of countries. Some analyses, which were performed at the disaggregated level, are also provided, as they are being used more and more. Finally, the paper summarizes and discusses the significant changes in aggregate road safety trend analysis which occurred during the period and provides recommendations for continuing these research efforts.  相似文献   

16.
Abstract

This paper examines whether a dwell time reduction on a high-intensity metro service, as a result of a series of accessibility enhancements, can contribute to an increased level of service and accessible public transport for passengers together with a reduction in costs for the operator. Actual train operation data were collected by on-site observations and from London Underground Ltd. A simple simulation is built to represent the effect on the overall cycle times of trains if certain parameters (e.g. dwell time) are changed. Four models are developed, concerning: (1) step height between train and platform, (2) an assumption of passenger service time to be no longer than 20 s, (3) door width and (4) the combination of step height and door width. From the application of the models it appears that the fourth model provides the highest reduction in dwell time and diminishes the overall cycle times of trains. However, it is the most expensive to implement as it requires work to raise platforms and the purchase of new rolling stock.  相似文献   

17.
It is often argued lately that the private sector should be allowed to build and operate roads in a transportation network at its own expense, in return it should receive the revenue from road toll charge within some years, and then these roads will be transferred to the government. This type of build–operate–transfer (B–O–T) projects is currently fashionable worldwide, especially for developing countries short of funds for road construction. One of the important issues concerning a highway B–O–T project is the selection of the capacity and toll charge of the new road and the evaluation of the relevant benefits to the private investor, the road users and the whole society under various market conditions. This paper deals with the selection and evaluation of a highway project under such a B–O–T scheme. For a given road network with elastic demand, mathematical models are proposed to investigate the feasibility of a candidate project and ascertain the optimal capacity and level of toll charge of the new highway. The response of road users to the new B–O–T project is explicitly considered. The characteristic of the problem is illustrated graphically with a numerical example.  相似文献   

18.
Estimation of origin–destination (O–D) matrices from link count data is considered. This problem is challenging because the number of parameters to be estimated is typically larger than the number of network links. As a result, it is (usually) impossible to identify a unique optimal estimate of the O–D matrix from mean link traffic counts. However, information from the covariance matrix of link count data collected over a sequence of days can relieve this problem of indeterminacy. This fact is illustrated through a simple example. The use of second-order statistical properties of the data in O–D matrix estimation is then explored, and a class of estimators proposed. Practical problems of model mis-specification are discussed and some avenues for future research outlined.  相似文献   

19.
When car users’ are questioned about the advantages and disadvantages of car use the focus should not be on what they say, but on how they present their arguments to the interviewer. This paper shows such arguments can differ in kind. Swedish car users present the advantages––such as ‘time-saving’––by referring to personal and direct experience. The disadvantages are of two kinds. Some are related to direct experience, such as ‘costs’. Some are made credible by reference to public discourse, notably ‘environmental degradation’. This indicates that the facts about the advantages and environmental impacts are constructed in different ways. Facts about the advantages and some of the disadvantages are constructed in a direct and unreflexive way, situated in practical actions, and leave little room for negotiation. Facts about environmental impacts are constructed by others in a distanced and reflexive process, situated in laboratories, etc. Car users adopt these facts through various media. While the arguments on the advantages of car use are presented as unquestionable and absolute, scientific facts about the negative effects of car use are presented as relative and negotiable. This should be seen as a possible explanation why people do not reduce their own car use, although they say that car use in general ought to be limited.  相似文献   

20.
Goodwin  P.B. 《Transportation》1989,16(2):121-154
Panel data are used to investigate what happens when people have some important transitions or changes in their life-cycle, employment status, income, or car ownership. Only three years data are available, and the pace of transition is slow: as a result relevant sample sizes are rather small. The analysis is carried out in two stages: results are given from a two year period, and these are used to generate hypotheses checked with data from the third year.It is found that in many cases the effects on mobility are different from what would be expected from cross-section data. In particular:
–  - car ownership changes are substantially less than expected;
–  - public transport does not benefit as much as expected when people become members specific dependent or captive groups.
  相似文献   

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