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991.
The transportation sector faces increasing challenges related to energy consumption and local and global emissions profiles. Thus, alternative vehicle technologies and energy pathways are being considered in order to overturn this trend and electric mobility is considered one adequate possibility towards a more sustainable transportation sector.In this sense, this research work consisted on the development of a methodology to assess the economic feasibility of deploying EV charging stations (Park-EV) by quantifying the tradeoff between economic and energy/environmental impacts for EV parking spaces deployment. This methodology was applied to 4 different cities (Lisbon, Madrid, Minneapolis and Manhattan), by evaluating the influence of parking premium, infrastructure cost and occupancy rates on the investment Net Present Value (NPV). The main findings are that the maximization of the premium and the minimization of the equipment cost lead to higher NPV results. The NPV break-even for the cities considered is more “easily” reached for higher parking prices, namely in the case of Manhattan with the higher parking price profile. In terms of evaluating occupancy rates of the EV parking spaces, shifting from a low usage (LU) to a high usage (HU) scenario represented a reduction in the premium to obtain a NPV = 0 of approximately 14% for a 2500 € equipment cost, and, in the case of a zero equipment cost (e.g. financed by the city), a NPV = 0 was obtained with approximately a 2% reduction in the parking premium. Moreover, due to the use of electric mobility instead of the average conventional technologies, Well-to-Wheel (WTW) gains for Lisbon, Madrid, Minneapolis and Manhattan were estimated in 58%, 53%, 52% and 75% for energy consumption and 66%, 75%, 62% and 86% for CO2 emissions, respectively.This research confirms that the success of deploying an EV charging stations infrastructure will be highly dependent on the price the user will have to pay, on the cost of the infrastructure deployed and on the adhesion of the EV users to this kind of infrastructure. These variables are not independent and, consequently, the coordination of public policies and private interest must be promoted in order to reach an optimal solution that does not result in prohibitive costs for the users.  相似文献   
992.
This paper measures the potential effects of low water levels on the Rhine and Danube navigation in the context of weather variability and a number of climate change scenarios. A long-term multimodal network transport analysis over the period 2005–2050 is presented; it analyzes the impact of changes on the water depth conditions on transport costs and the modal splits between three competing modes. The results indicate that the impact of climate change until 2050 should be limited.  相似文献   
993.
刘安  张晖 《船海工程》2012,41(2):67-70
介绍新型环保灭火剂作为船用产品在国内船舶上使用的现状,对其中几种环保灭火剂的综合性能进行了分析比较,结合其各自的性能特征以及国内外相关技术要求,提出了新型环保灭火剂在我国内河船舶上应用的建议。  相似文献   
994.
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   
995.
Abstract

This paper analyses the productivity of a representative sample of African seaports from 2002 to 2008. Productivity scores are decomposed, based on the Luenberger productivity indicator, and the nature of technological change is analysed. The paper finds that Nigerian seaports are the most efficient, followed by Angola and Mozambique. Discussions of the results as well as related policy implications are provided.  相似文献   
996.
Marine resource management and related stakeholder conflicts have been clearly defined in recent decades as pressing issues worldwide. This article provides a comparative study of the management regimes of the Gulf of Castellammare Fishery Reserve and the Egadi Islands Marine Reserve in Sicily, Italy. What managers in these two reserves have neglected to include in management is a social science evaluation scheme to ensure the development of more effective overall management. This is a significant problem in both Italy and the rest of the Mediterranean, where few sociocultural and economic studies have been conducted. Using data collected with standard anthropological field methods, analysis was conducted on how artisanal fishers are impacted by reserves, the extent of their knowledge regarding regulations, their opinions on management, and demographics. The results indicate that while fishers in the two case studies are all aware of the marine reserves where they fish, most fishers are not well informed of the associated regulations. Fishers feel alienated from the management process, and would feel more comfortable with reserve managers and regulations if they were involved in management. The article concludes by showing how such data could help to develop more useful and practical management practices in both these and other MPAs with similar problems.  相似文献   
997.
The integration of climate change adaptation considerations into management of the coast poses major challenges for decision makers. This article reports on a case study undertaken in Christchurch Bay, UK, examining local capacity for strategic response to climate risks, with a particular focus on issues surrounding coastal defense. Drawing primarily on qualitative research with local and regional stakeholders, the analysis identifies fundamental disjunctures between generic concerns over climate change and the adaptive capacity of local management institutions. Closely linked with issues of scale, the problems highlighted here are likely to have broad and continuing relevance for future coastal management elsewhere.  相似文献   
998.
The “no net wetland loss” goal has not been met in urban coastal regions where conditions continue to exacerbate wetland losses. Under the Clean Water Act (Section 404) the U.S. Army Corps of Engineers and U. S. Environmental Protection Agency share responsibility for regulating placement of fill material in wetlands. The `no discharge of fill' rules threaten coastal wetlands with continuing losses due to effects of changing climate, including rising sea levels, higher storm surges, and flooding. Where inland migration is limited by development, or where sediment accretion rates are lower than the rate of sea level rise, urban wetlands will be lost unless marsh topography is elevated. We explored regulatory and design approaches in recent Hudson-Raritan Estuary (HRE), San Francisco Bay Estuary and coastal Louisiana restorations, including creation of new marshland using dredge material. Questions related to sea level rise, ecological position within the landscape, or potential effects of extreme storm events were not addressed in the HRE restoration designs; these concerns were taken into account in other regions. We suggest benefits of marsh `replenishment' should be acknowledged in Federal regulatory policy and that consistent policies supportive of low-lying coastal marsh preservation in all regions should be enacted.  相似文献   
999.
Abstract

Marine and coastal zone policy represents a collaboration of people managing and people managed. This paper takes a holistic stance in suggesting that marine communities are viewed properly as networks of focused interest groups, policymakers, professionals, and publics. The interplay between culture and marine and coastal policy is appropriately one topic of applied social research. Seven ethnographic studies in this domain are introduced in this theme issue and help us to understand sociocultural processes and institutions bearing on marine affairs.  相似文献   
1000.
文章以绍兴市曹娥江袍江大桥多跨连拱结构施工工程为例,阐述了超长系杆设计、系杆张拉施工安装的工艺以及系杆张拉和临时系杆放张的体系转换施工流程及控制方法,为同类型桥梁系杆施工提供参考。  相似文献   
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