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排序方式: 共有2137条查询结果,搜索用时 670 毫秒
921.
The study develops scenarios regarding the introduction of electric vehicles to the passenger vehicle fleet of Norway to reach the 2020 Norwegian greenhouse gas reduction target and a more extreme target to limit global temperature increase to two degrees. A process-based life cycle assessment approach is integrated with a temporally variable inventory model to evaluate the environmental impacts of these scenarios. We find that greenhouse gases in the reference scenario increase by 10% in 2020 in comparison to 2012; while for the more intensive improvements in conventional vehicles, this increase is reduced to 2%. For electric vehicles deployment scenarios, although the fleet share will reduce the tailpipe greenhouse gas emissions by 8–26%, with the upper end representing the two-degree reduction target, emissions reductions over the entire life cycle are only 3–15%. Electric vehicles also reduce emissions of NOx, SO2 and particulates reducing acidification, smog formation and particulate formation impacts, however, with addition of large numbers of electric vehicles significant trade-offs in toxicity impacts are found. 相似文献
922.
We assess existing and potential charging infrastructure for plug-in vehicles in US households using data from the American Housing Survey and the Residential Energy Consumption Survey. We estimate that less than half of US vehicles have reliable access to a dedicated off-street parking space at an owned residence where charging infrastructure could be installed. Specifically, while approximately 79% households have off-street parking for at least some of their vehicles, only an estimated 56% of vehicles have a dedicated off-street parking space – and only 47% at an owned residence. Approximately 22% vehicles currently have access to a dedicated home parking space within reach of an outlet sufficient to recharge a small plug-in vehicle battery pack overnight. Access to faster charging, required for vehicles with longer electric range, will usually require infrastructure investment ranging from several hundred to several thousand dollars, depending on panel and construction requirements. We discuss sensitivity of results to uncertain factors and implications for the potential of mainstream penetration of plug-in vehicles. 相似文献
923.
何伟荣 《电力机车与城轨车辆》2006,29(1):10-12
随着轨道交通不断发展,地铁车辆投入逐年递增,运营中的地铁列车的性能、安全等问题引起国内外的地铁车辆运营商的高度重视,在地铁车辆上安装地铁车辆运营记录仪成为非常必要,文章介绍一种新技术——非接触式检测方式,并应用于目前的国内地铁车辆。 相似文献
924.
925.
航运国际化的发展和航运人才要求的提高,对航海专业教师的要求也越来越高。本文从三个方面进行分析,阐述了航海专业教师上船任职锻炼的必要性。 相似文献
926.
In this study several hypotheses comprising a heuristic framework derived from rational-choice (RC) premises and regarding some potentially influencing variables on future use intention of different vehicle types are tested with a rural area sample. Especially the differentiation between long-term vs. short-term as well as functional/rational vs. extra-functional/emotional motivators is assessed. Results suggest a predominance of functional motivators and rational connotations over extra-functional/emotional ones. The models to check whether short-term or long-term effects dominate did not clearly confirm a predominance of long-term factors as hypothesized. In several regression models a moderating effect of rational short-term connotations on different long-term motivators was found, thus contributing notably to the prediction of future vehicle use-intention. The need for further research and theory-driven modeling is briefly discussed. 相似文献
927.
The suitability of an electric vehicle of a given range to serve in place of a given conventional vehicle is not limited by the daily travel over distances within that that range, but rather by the occasional inconvenience of finding alternative transport for longer trips. While the frequency of this inconvenience can be computed from usage data, the willingness of individual users to accept that replacement depends on details of available transportation alternatives and their willingness to use them. The latter can be difficult to assess. Fortunately, 65% of US households have access to the most convenient alternative possible: a second car. In this paper we describe an analysis of prospective EV acceptance and travel electrification in two-car households in the Puget Sound region. We find that EVs with 60 miles of useful range could be acceptable (i.e. incur inconvenience no more than three days each year) to nearly 90% of two-car households and electrify nearly 55% of travel in those households (32% of all travel). This compares to 120 miles range required to achieve the same fraction of electrified travel via one-for-one replacement of individual vehicles. Even though only one third of personal vehicles in the US may be replaced in this paradigm, the ‘EV as a second-car’ concept is attractive in that a significant fraction of travel can be electrified by vehicles with modest electric range and virtually no dependence on public charging infrastructure. 相似文献
928.
航标遥测遥控系统实现方案的探讨 总被引:2,自引:0,他引:2
从建设实践出发,提出适合长江航道管理模式的航标遥测监控系统的构架方案,并针对数据通信方式、数据平台标准以及航标定位等问题进行分析和研究,为今后内河航标遥测监控系统的大规模建设提出建设性意见。 相似文献
929.
930.
Despite the recent commercial success of hybrid, plug-in hybrid and electric vehicles their market share is still insufficient to produce either a significant impact on energy consumption on a global basis or a profitable automotive segment. In this context, the possibility of upgrading conventional vehicles to hybrid electric vehicles is gaining increasing interest.To this aim this paper investigated and modelled the intention to install an after-market hybridization solar-kit (HySolarKit) in order to ascertain the main behavioural determinants of the choice process and set up an operational model with which to estimate the market potential of such technology. In particular, two behavioural stages of the choice process were analysed and modelled: (i) the intention to adopt the HySolarKit; (ii) the choice to install the HySolarKit. Both issues were addressed through ad hoc stated preference surveys carried out in two different Italian cities, and through the specification and the calibration of discrete choice models based on the behavioural paradigm of random utility theory. Different modelling solutions (homoscedastic and heteroscedastic) were compared in terms of goodness-of-fit and sensitivity to level-of-service attributes. The results showed the technological potential of the HySolarKit, and that both behavioural stages may be effectively modelled through random utility theory. Estimation results allowed an interpretation of the main determinants of the investigated phenomena, making it possible to quantify the potential effects and the concerns towards such a green solution, and making it possible to draw up operative marketing strategies. In particular, the intention to adopt the kit mainly depends on socio-economic factors as well as activity-related and attitudinal attributes, whereas the probability of installing the kit is greatly affected, to the same extent, by installation cost, the charging cost and the weekly mileage driven. 相似文献