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21.
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   
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Sales tax measures passed at the local level and dedicated to transportation projects have become increasingly popular in the United States. While revenues from fuel taxes stagnate, growth of local transportation sales taxes (LTSTs), most approved in local elections, has led to a gradual shift of the financial base for transportation projects away from user fees and toward broader-based taxes. In this study, the relationship between voter support and the social, political, and geographic characteristics of the voters is explored. Using precinct-level voting data and census demographic data for three local transportation sales tax elections in Sonoma County, in the San Francisco Metropolitan area of California, regression models were constructed to analyze this relationship. In addition, the relationship between the outcomes of the three measures was explored to better understand which transportation projects might have garnered more support for the successful measure. It was found that the closer voters lived to the transportation projects to be funded, the greater their support. Higher incomes were also positively related to support, controlling for other variables. Political leanings were found to affect support, with the direction of the effect dependent upon the project list in each measure’s expenditure plan. Finally, it appears that the latest measure, which passed successfully, benefited greatly from its multi-modal expenditure plan.  相似文献   
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Urban transportation policy during the nineteen seventies has been characterized by attempts to deal with four major problems: 1) the minimization of environmental impacts of transport investments, 2) the alleviation of inequities in mobility, and financial burdens imposed upon some groups by earlier investments in capital intensive highway networks, 3) the accommodation of demands for public participation in transport decision-making, and 4) the precipitous rise of public transit operating costs. In this paper examples are given of policies which have been pursued in attempting to solve each of these problems. It is shown that policies designed to solve one of them have often intensified others. Thus, current policy is characterized by reliance upon very small-scale and timid plans and proposals. The eighties may see a return to large-scale and comprehensive transport plans, but these will not be exclusively physical or system plans. Rather, transportation plans in the eighties will include a balance among physical facilities, institutional arrangements, financial plans, and user incentives and disincentives. Several examples of such comprehensive policies are given in this paper.Paper prepared for presentation at the Fourth World Congress of Engineers and Architects in Tel Aviv, Israel, December, 1976.  相似文献   
27.
A small electrically powered city car has been developed for self-drive hire in the centre of Amsterdam; 35 of these cars are now available to hire from 5 stations in the city centre. The. system has been designed for fully automatic control, including direct debit of hirers' accounts at the Amsterdam Savings Bank. The system, which was conceived in 1969 by an industrial designer and former city councillor to reduce traffic in central Amsterdam, failed to win the support of the City Council and has since been developed by a specially formed co-operative society. The co-operative managed to raise loans of US$ 250,000 for the first phase which has now been completed. This included the design and construction of the vehicles, the purchase of a mini-computer for the central control system, development of the control software and construction of the first five stations. A further 10 stations are scheduled for operation by the end of 1976, by which time the fleet should be extended to 100 vehicles. The ultimate target is 150 stations and 1000 vehicles.  相似文献   
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Trace metal inventories and transboundary fluxes were estimated for the surface waters of the eastern Gotland Basin, and a mass balance for this water body was derived.The study area was delineated by a box which bordered vertically by the sea surface and the halocline and horizontally by the coast of Gotland and the coast of Latvia/Lithuania. For the calculation of the trace metal inventories in the box, a high-resolution sampling was carried out during different seasons. Additional sediment trap studies were performed to calculate the vertical particulate trace metal fluxes through the halocline.The following transboundary fluxes have been estimated: (a) atmospheric input of trace metals; (b) lateral transport from adjacent bodies of surface water; (c) diapycnal fluxes of dissolved trace metals at the halocline; (d) sinking of trace metals, associated with particles, through the halocline, (e) vertical advection through the halocline.The lateral transport into and out of the surface box is important for the metals (Cd, Cu, Zn) with “nutrient-like” behaviour. For particle reactive elements like lead, vertical sedimentation and lateral transport out of the box as much as atmospheric input and lateral input into the box are in the same order of magnitude. Turbulent diapycnal mixing plays a minor role compared to the advective fluxes.The estimated range for the residence times for the region under investigation are  0.5–1.3 years for Pb;  2–11 years for Zn,  7–36 years for Cd and 42–89 years for Cu. This demonstrates that the system reacts very fast for particle reactive elements like Pb, while for copper sedimentation processes are not the preferential sink and can be neglected.  相似文献   
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When designing an arctic cargo ship, it is necessary to consider multiple stochastic factors. This paper evaluates the merits of a simulation-based probabilistic design method specifically developed to deal with this challenge. The outcome of the paper indicates that the incorporation of simulations and probabilistic design parameters into the design process enables more informed design decisions. For instance, it enables the assessment of the stochastic transport capacity of an arctic ship, as well as of its long-term ice exposure that can be used to determine an appropriate level of ice-strengthening. The outcome of the paper also indicates that significant gains in transport system cost-efficiency can be obtained by extending the boundaries of the design task beyond the individual vessel. In the case of industrial shipping, this allows for instance the consideration of port-based cargo storage facilities allowing for temporary shortages in transport capacity and thus a reduction in the required fleet size / ship capacity.  相似文献   
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Analysing the impact of urban policy interventions on urban growth, land use and transport (LUT) is crucial for urban planners, transport planners and policy-makers, especially in rapidly growing cities. This paper presents a cellular automata-based land-use/transport interaction model – Metronamica-LUTI – for Jeddah that is used to analyse the impact of different proposed policy interventions under two urban growth scenarios for the period 2011–2031. Used as an integrated policy impact assessment tool, the model demonstrates a strong reciprocal relationship between LUT in Jeddah. This study shows that relevant spatial information and integrated policy impact assessment can provide rich insights into the interaction between LUT, the appropriate policy to consider in place and time which traditional planning practice and typical static urban models cannot do.  相似文献   
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