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Current car technologies will not solve upcoming challenges of mitigating greenhouse gas emissions in road transport. Projections of the market penetration by alternative drive train technologies are controversial regarding both forecast market shares and applied scientific methods. Accepting this latter challenge, we provide a (so far missing) overview of methods applied in this field and give some recommendations for further work. Our focus is to classify the applied methods into a convenient pattern and to analyse models from the recent scientific literature which consider the electrification of light-duty vehicles. We differentiate the following bottom-up approaches: Econometric models with disaggregated data (such as discrete choice), and agent-based simulation models. The group of top-down models are subdivided into econometric models with aggregated data (e.g. vehicle stock data), system dynamics, as well as integrated assessment models with general equilibrium models. It becomes obvious that some methods have a stronger methodological background whereas others require comprehensive data sets or can be combined more flexibly with other methods. Even though there is no dominant method, we can identify a trend in the literature towards data-driven hybrid approaches, which considers micro and macro aspects influencing the market penetration of electric vehicles.  相似文献   
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A case study located in Auckland, New Zealand, was used to quantify the magnitude of savings that may result if the SCATS adaptive traffic control system contains an explicitly combined queue estimation and offset adjustment on a cycle‐by‐cycle basis. A validated SATURN traffic model was used to evaluate five scenarios that represent the short‐run and long‐run efficiency gains resulting from progressive signal adaption with an objective of queue minimisation on the main corridors. Optimisation was applied both area‐wide, and on selected arterial corridors, using a combined split/offset optimisation routine with responsive driver behaviour to achieve a network‐wide and corridor‐specific efficiency gain. The modelling heuristic evaluates the efficiency of both the Equisat and P0 optimisation policies that would mimic a more progressive adaption of signals under SCATS. Results for the long‐run area‐wide optimisation can produce network‐wide travel‐time savings in the order of 20% and a reduction in transient queues of 28% if only selected corridors are optimised, with a 5% reduction in journey time over an average 8‐min journey. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
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Ship manoeuvring is something that many seafarers perform, although little attention has been devoted to this in research literature. The topic has generally been explained by members of the trade as gaining knowledge through experience. The purpose of this study was to identify which factors contribute to the perceived state of a ship’s physical condition during manoeuvring. Eight master mariners were interviewed. The data resulted in a division of a sea voyage into three different phases, each requiring varying levels of effort from the bridge crew. The results further describe how the shiphandler strives for harmony between his ship and the environment. This is accomplished by personal factors such as spatial awareness, knowledge and experience to handle environmental factors of context, situation and vessel specific factors of inertia and the use of navigational instruments.  相似文献   
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Abstract

US airports negotiate legally binding contracts with airlines and finance large investment projects with revenue bonds. Applying insights from transaction cost economics, we argue that the observed variation in contractual and financing arrangements at US airports corresponds to the parties' needs for safeguarding and coordination. The case evidence presented reveals that public owners set the framework for private investments and contracting. We suggest that airline contracts and capital market control result in comparative efficient investments and act as a check on the cost inefficiency typically linked to public ownership.  相似文献   
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This paper assesses the economic justification for the selection of priority projects defined under the auspices of the Trans-European transport network. Three different transport models are used to analyse the costs and benefits associated with the current list of 30 priority projects. Most of these projects fail the cost-benefit test and few of the economically justifiable projects would need European subsidies to ensure their viability. Two remedies are proposed to minimise the inefficiencies surrounding project selection. The first remedy would oblige each member state or group of states to perform a cost-benefit analysis, followed by peer review and ensure that the results were published publicly prior to the ranking of federally funded priority projects. The second remedy would require federal funding to be made available only for projects with important spillovers to other countries in order to avoid pork barrel political behaviour.  相似文献   
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Despite the emphasis placed on the contextual nature of integrated coastal management (ICM) implementation in the literature, many uniformities are encountered in ICM implementation worldwide. In this article the tangled threads of ICM practice are unravelled and a theoretically founded set of criteria for evaluating the design of ICM implementation models is provided. First, paradigms in integrated environmental management (IEM) implementation, the broader domain within which ICM practice is nested, are characterized in terms of their key concepts. Next, the paradigms are used as a mechanism to distill uniformities in ICM practice as reported in review articles. Finally a set of fourteen building blocks against which the scientific credibility of contextual, country-specific ICM implementation models can be validated, is generated by translating the theory-based characterization into evaluation criteria readily accessible to practitioners.  相似文献   
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In this paper we suggest a methodology to predict commodity specific transportation flows that brings together data in value and in quantity terms in a consistent way. The approach is based on the modern gravity formulation. There are three driving forces of the transport flows dynamics: economic growth, the ongoing globalization (reduction of trade barriers), and the changing commodity composition of trade, whereby the evolution of value-to-weight ratios is explicitly taken into account. The methodology is applied to forecast the interregional trade flows in Europe.  相似文献   
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A review of wave-energy extraction   总被引:3,自引:0,他引:3  
Comparing ocean-wave energy with its origin, wind energy, the former is more persistent and spatially concentrated. In this paper wave spectrum parameters related to transport, distribution and variability of wave energy in the sea are educed. Many different types of wave-energy converters, of various categories, have been proposed. It is useful to think of primary conversion of wave energy by an oscillating system as a wave-interference phenomenon. Corresponding to optimum wave interference, there is an upper bound to the amount of energy that can be extracted from a wave by means of a particular oscillating system. Taking physical limitations into account, another upper bound, for the ratio of extracted energy to the volume of the immersed oscillating system, has been derived. Finally, the significance of the two different upper bounds is discussed.  相似文献   
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