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31.
Road safety is a policy priority due to the high casualties and costs associated with road accidents. Since speed is a major cause of road accidents, in‐vehicle speed limiters or Intelligent Speed Adaptation (ISA), seems a promising solution. ISA implementation, however, is hindered by large uncertainties, for example about the impacts of ISA, the way users might respond to ISA, and the relationship between speed and accidents. Traditional Multi‐Criteria Analysis (MCA) has limitations in handling these uncertainties. We present an MCA approach based on exploratory modeling, which uses computational experiments to explore the multiple outcomes of ISA policies (safety, emissions, throughput, and cost) across a range of future demand scenarios, functional relationships for performance criteria, and user responses to ISA. As an illustration, by testing the impacts of different ISA penetration levels on two driver groups, we show that when compliance with ISA is expected to be low, a policy aimed only at novice drivers outperforms other ISA policies on safety improvement.  相似文献   
32.
For a large number of applications conventional methods for estimating an origin destination matrix become too expensive to use. Two models, based on information minimisation and entropy maximisation principles, have been developed by the authors to estimate an O-D matrix from traffic counts. The models assume knowledge of the paths followed by the vehicles over the network. The models then use the traffic counts to estimate the most likely O-D matrix consistent with the link volumes available and any prior information about the trip matrix. Both models can be used to update and improve a previous O-D matrix. An algorithm to find a solution to the model is then described. The models have been tested with artificial data and performed reasonably well. Further research is being carried out to validate the models with real data.  相似文献   
33.
An efficient transport system is a crucial precondition for economic development and an asset in international mobility. Mobility of passengers and transport of goods are considered key elements for a modern society. The transport sector is also a sector of continuous technological innovation. However, there is considerable uncertainty surrounding future transport technology and policy, as well as a large variation in ways to deal with this uncertainty. With regard to the latter it may be helpful to use more than one foresight method, e.g. a combination of methods each with a different emphasis on expertise, creativity and interaction with actors. Such a multiple method approach allows for the identification of those futures or future developments that are robust. This paper provides an introduction to the topic of transport innovation as well as providing a context for the four papers which follow in this special issue, illustrating the importance of taking such a multiple method approach.  相似文献   
34.
The trans-European transport network (TEN-T) encompasses the major planned transport infrastructure in Europe, ranging from high speed rail to port infrastructure. Projects in this category are considered priority projects and receive European subsidies; but these have been insufficient to get these projects off the ground. This paper addresses two research questions. First, it sketches the basic economics of cross-boundary infrastructure projects: what pricing and investment policies can we expect, what is the role of through traffic and high fixed costs of infrastructure? Second, it examines briefly what lessons the EU could draw from the experience of other existing federal funding institutions like the US and Germany. These ideas are used to propose a new subsidy scheme for the TEN-T projects.  相似文献   
35.
This article recommends the parallel but separate modeling of nature-based and people-based marine protected areas (MPA) before the design and siting stages of establishing an MPA. Separate but simultaneous modeling of ideal nature and people MPAs permits each to be maximized for its own variables and subsequently compared to identify conflicts and agreements. The case that supports this recommendation is in the Commonwealth of the Bahamas, where the study conducted 572 interviews with people from six traditional settlements in the central Exumas Islands and Cays. The research is focused on why members of these settlements differentially responded to three nearby national MPA proposals.  相似文献   
36.
Sacrificial anodes have become a standard practice for the protection of ballast tanks of merchant vessels against corrosive damage. A well protected tank should extend the life span of a ship and consequently enhances its economic value. An in situ survey comprising more than 100 merchant vessels provided the opportunity to measure the impact of these anodes on the life expectancy of these vessels. Contrary to the general belief of these anodes’ beneficial effect, no significant difference was found in our observations in terms of corrosion occurrence between ship populations with and without sacrificial anodes, across all ship ages. This may be explained by the highly variable conditions and the complex geometry in a ballast tank severely impede optimal and straightforward installation of these anodes in these tanks. Also, poorly placed anodes in it may harm the integrity of the coating of the tank. We therefore plead for uniform and clear rules on anode installation and inspection.  相似文献   
37.
Many decisions taken by mankind are rational only to a limited extent. This holds for individual travel behaviour, but also for long-range strategic decisions on transport systems or transport technology. In any decision problem, coping with uncertainty is the most critical element. The introduction of new transport technology is surrounded by uncertainty. For example, there is uncertainty about the pace and extent of adoption of new technology and there is uncertainty about the impact of new technology in terms of increased sustainability or increased efficiency. This article maps uncertainty surrounding new transport technology and identifies ways in which to deal with uncertainty in policy making. The findings will be illustrated with electric vehicles, particularly with two specific strategies to deal with uncertainty: interactive technology watching and experimentation in a market niche. The paper concludes with a discussion of success factors that influence the outcomes of such strategies.  相似文献   
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39.
Abstract

Catch share programs are used in fisheries management to meet goals such as species recovery, overcapacity reduction, and economic efficiency. Anticipated impacts include fleet consolidation, infrastructure reduction, and social disruption within communities. The Pacific Coast Groundfish Fishery Social Study (PCGFSS) aims to understand social changes related to the recently implemented West Coast Groundfish Trawl Catch Share Program. In this article, we use a subset of PCGFSS data to explore the ways remaining fishery participants have thus far adapted to catch shares. While some vessels have left the fishery, we found that many participants are adapting to this catch shares program despite challenges. Quota leasing strategies, fishery diversification, gear innovation, and community quota funds are some of the tools participants are using to continue operating under the catch shares program. These early challenges and adaptations to the catch share program are worthy of continued tracking, as researchers, managers, and fishing communities, would benefit by considering first-hand perspectives of the on-the-ground realities of harvesting groundfish in the rationalized fishery.  相似文献   
40.
Over the last decade, insights from the strategic management discipline have increasingly been applied to ports. A review of literature shows that in the analysis of port authority strategy, mainly outside-in approaches are applied. This paper adds to the emerging understanding of the port authority’s strategy by applying a cognitive perspective. Specifically, the strategic cognition of firms’ executives is one of the explanatory variables behind firms’ strategic decisions. Furthermore, cognitions are influenced by the organisational contexts in which port authority executives have worked. As a result, managerial “mental maps’ may vary across industry contexts and over time. This research investigates the strategic cognition of a global set of port authority executives through a survey-based instrument. The results show that, to a large extent, PAs resemble “regular” for-profit companies, but that they possess some specific beliefs that distinguish them from “regular” companies.  相似文献   
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