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31.
This article introduces a theme issue of the Coastal Management Journal comprising a set of articles on the potential economic benefits from new investments in coastal ocean observing systems. We describe a methodology to estimate these benefits, and apply this methodology to generate preliminary estimates of such benefits. The approach focuses on coastal ocean observing information within ten geographic regions encompassing all coastal waters of the United States, and within a wide range of industrial and recreational activities including recreational fishing and boating, beach recreation, maritime transportation, search and rescue operations, spill response, marine hazards prediction, offshore energy, power generation, and commercial fishing. Our findings suggest that annual benefits to users are likely to run in the multiple $100s of millions of dollars. The project results should be considered first-order estimates that are subject to considerable refinement as the parameters of regional observing systems are better defined, and as our understanding of user sectors improves.  相似文献   
32.
Long‐distance trips are generally under‐reported in typical household surveys, because of relative low frequency of these trips. This paper proposes to utilize location data from cellular phone systems in order to study long‐distance travel patterns. The proposed approach allows passive data collection on many travelers over a long period of time at low costs. The paper presents the results of a study that applies cellular phone technology to assess trips at the national level. The method was specifically designed to capture long distance trips, as part of the development of a national demand model conducted for the Economics and Planning Department of the Israel Ministry of Transport. The method allows the construction of origin–destination tables directly from the cellular phone positions. The paper presents selected results to illustrate the potential of the method for transportation planning and analysis. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   
33.
Understanding and Modeling the Human Driver   总被引:4,自引:0,他引:4  
Summary This paper examines the role of the human driver as the primary control element within the traditional driver-vehicle system. Lateral and longitudinal control tasks such as path-following, obstacle avoidance, and headway control are examples of steering and braking activities performed by the human driver. Physical limitations as well as various attributes that make the human driver unique and help to characterize human control behavior are described. Example driver models containing such traits and that are commonly used to predict the performance of the combined driver-vehicle system in lateral and longitudinal control tasks are identified.  相似文献   
34.
"清新的空气,宽敞的空间,伟大的梦想和重生的感觉",传奇导演约翰·福特在1950年代这样描述美国西部片。在60年后的今天,这句话正好可以用来形容亚当·基梅尔(ADAM KIMMEL)最新的男装。在众多男设计师之中我们大爱的他,能以极快的速度并在极少的时装季里通过男模来表现出他对潮流的看法。  相似文献   
35.
This paper addresses methodological issues in cost–benefit analysis (CBA) regarding congestion charging schemes. Despite suspicion on the reality of travel time savings, it is argued that these savings are a conservative value of surplus gained from a congestion scheme. The methodology of measurement of travel time reliability is not yet stabilised, but the literature review suggests that it may take a growing share of benefits in the future. Sensitivity tests performed on the London and Stockholm case studies with a simulation model underline the need to accurately measure speeds, while the value of travel time appears less critical. Finally, the impact of costs of public funds on public accounts is greatly significant and may increase in the future.  相似文献   
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Availability and affordability of reliable transportation – either through public transportation or individual ownership of automobiles – appears necessary to support a successful transition from welfare to work. One approach adopted by state and local governments is to subsidize vehicle acquisition by welfare recipients in transition. To date there are no empirical studies that analyze the impacts or effectiveness of these vehicle subsidy programs. The objective of this study is to examine the extent to which participation in a small-scale vehicle donation-and-sales program in Vermont increases earned income by individuals in transition from welfare to work. Using reduced-form random effects and censored regression models to account for the simultaneity of decisions to work and participate in welfare programs, we examine the impacts of this vehicle acquisition program for a small group of individuals. Our analyses indicate that the program results in a statistically significant increase in both earned income and the probability of employment.  相似文献   
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THENEURONSDOUBLE-LABELLEDBYSEROTONINANDGLUTAMATE-IMMUNOREACTIVITYINMEDULLARYRAPHENUCLEIPROJECTINGTOTHECEREBELLARCORTEXOFTHEKI...  相似文献   
40.
With 8.76 million residents in 2011, the population of Southern Ontario’s Greater Golden Horseshoe (GGH) has grown dramatically over the past decades, driven by net domestic in-migration and immigration. Corresponding to its growth in population, commuting distances and times within the region have grown as well. Yet, despite the number of immigrants that the region attracts on a yearly basis, there is comparatively little information on commute distances. Consequently, this paper examines commuting distance amongst immigrants in the GGH. Specifically, it evaluates commute distance by immigrant status (immigrants and native born), along with how commute distance differs by arrival cohort and ethnic and racial population groups. Results indicate that commute distance increases with increasing duration of residence, with differences by race and ethnicity.  相似文献   
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