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101.
This article presents the results of a scenario-based study carried out at the European Commission’s Joint Research Centre aimed at analyzing the future growth of aviation, the resulting fuel demand and the deployment of biofuels in the aviation sector in Europe. Three scenarios have been produced based on different input assumptions and leading to different underlying patterns of growth and resulting volumes of traffic. Data for aviation growth and hence fuel demand have been projected on a year by year basis up to 2030, using 2010 as the baseline. Data sources are Eurostat statistics and actual flight information from EUROCONTROL. Relevant variables such as the number of flights, the type of aircrafts, passengers or cargo tonnes and production indicators (RPKs) are used together with fuel consumption and CO2 emissions data. The target of the European Advanced Biofuels Flightpath to ensure the commercialization and consumption of 2 million tons of sustainably produced paraffinic biofuels in the aviation sector by 2020, has also been taken into account. Results regarding CO2 emission projections to 2030, reveal a steady annual increase in the order of 3%, 1% and 4% on average, for the three different scenarios, providing also a good correlation compared to the annual traffic growth rates that are indicated in the three corresponding scenarios. In absolute values, these ratios correspond to the central, the pessimistic and the optimistic scenarios respectively, corresponding to 360 million tonnes CO2 emissions in 2030, ranging from 271 to 401 million tonnes for the pessimistic and optimistic scenarios, respectively. This article also reports on the supply potential of aviation biofuels (clustered in HEFA/HVOs and biojet) based on the production capacity of facilities around the world and provides an insight on the current and future trends in aviation based on the European and national policies, innovations and state-of-the art technologies that will influence the future of sustainable fuels in aviation.  相似文献   
102.
This paper explores the relationships between the spatial patterns of the distribution of the young hakes of the year (YOY) and the oceanographical features in two areas of the Central Mediterranean (the Ligurian Sea and the Strait of Sicily), characterised by the occurrence of straits and channels. Comparative and correlative approaches were used to investigate coupling between biological and physical patterns. Density indices of the YOY were derived from annual trawl surveys from 1994 to 2004 in spring and autumn. Mean patterns of the YOY distributions were compared with the mesoscale oceanographical features reported in literature. No evident trends in recruitment strength were found in either areas. Inter-annual variability in YOY abundance in the Ligurian Sea was higher than in the Strait of Sicily. The location of nursery grounds in the study areas coincides with zones of relatively higher production, where upwelling and other enrichment processes regularly occur. The presence of predictable eddies and the frontal systems play a major role in the localization of nursery areas in the Strait of Sicily, maintaining their stable position throughout the years. The strongest transport of southern waters from the Tyrrhenian to the Ligurian Sea, due to the East Corsica Current, which is negatively correlated to winter North Atlantic Oscillation, is associated with the highest abundance of hake recruits in the nurseries of the Northern Ligurian Sea.  相似文献   
103.
薛辉  唐涛 《都市快轨交通》2007,20(1):79--82
说明随着城市轨道交通系统在我国的蓬勃发展,传统的车载列车显示系统已经越来越不能满足安全性的要求,而通过嵌入式实时操作系统(VxWorks)开发的车载列控显示系统可以满足这方面需求,且具有多任务的特点.通过基于通信列车控制(CBTC)的车载控制器(VOBC)子系统中的车载列控显示系统的设计和实现,介绍VxWorks在车载列控显示系统中的应用.认为从多任务的角度,可以更好地解决车载列控显示系统对安全性的需求.  相似文献   
104.
邢澍 《国外铁道车辆》2007,44(3):1-6,33
阐述了俄罗斯与前苏联铁路货车的发展过程,介绍了各个时期货车的保有量、本国制造量与进口量,以及几种货车及其转向架的主要技术参数,并概述了近年来俄罗斯铁路保温车状况.  相似文献   
105.
本文以2011年为例对欧洲男子篮球锦标赛的特点进行分析.2011年欧洲男篮锦标赛也是2012年伦敦奥运会欧洲区的预选赛,比赛中,多支球队实力接近,争夺激烈.与弱队相比,强队的主要优势表现为内线球员的身高占优、内线攻击的比重大且效率高、防守能力强.而在实力接近的强强对抗中,防守的破坏性加剧,此时,防守质量及外围远投成为决定胜负的关键.  相似文献   
106.
介绍欧盟防盗法规R116的主要内容,讲述转向机构锁止系统的法规符合性设计事例、车辆报警系统(VAS)的法规符合性设计事例、发动机止动装置的法规符合性设计事例。为自主品牌汽车的法规适应性设计提供参考。  相似文献   
107.
With a large number of railway development projects in Europe and worldwide, which once completed will be serving rail passengers of the future, this paper aims to take a step back and evaluate current railway systems performance. The objectives are to compare statistical data on various passenger-related parameters of the railway system in a number of selected European countries and draw conclusions on the level of their performance when compared to the European average.Analyses of publically available statistical data, extracted from the Eurostat service at a European level will allow for a comparison of various indicators which influence the performance of the railway systems from an infrastructure and operational perspectives. The analyses will also allow identifying key performance indicators for the accurate assessment of the rail systems.The paper will highlight case studies for various parameters which are important to stakeholders of the railways, including infrastructure managers, rail operators, policy makers and the end users. This knowledge will be to the benefit of today’s railway industry as well as the rail systems of the future, as it will show trends drew upon existing data which might continue in the future.  相似文献   
108.
The implementation of transport infrastructure plans often has significant impacts on landscapes, especially where new roads and railroads are built. Key decisions regarding the building of new transport infrastructures are often made on a strategic level, where the long-term development of a region is determined, and before the infrastructure project actually begins. In this paper we build on previous advances in Strategic Environmental Assessment theory by linking the process-related issues of the integration of these assessments in general to landscape issues in particular; we use a multiple case study of Swedish transport planning.Results of this study indicate that the particular planning processes we looked at failed to carry out strategic landscape assessments and integrate landscape assessments in the planning process. We conclude that this can be explained by the flawed procedure of assessing landscape, the unhelpful structuring of SEA reports and by process-related issues. The idea of applying a holistic understanding of landscape, in line with the ELC, was notably absent from the studied cases. The lack of consideration of landscape as a whole can be attributed to poor use of dissipated and fragmented knowledge about landscapes as well as weaknesses in the assessment procedure. Our results indicate that the traditions of EIA are still prevalent in the practice of SEA, despite the fact that SEA theory has moved away from EIA-based methodology to become a tool for integrating environmental concerns into decision-making and for paying close attention to strategic decision processes.  相似文献   
109.
介绍采用中国加工的生产设备,利用中国工艺生产欧标双块式轨枕,为今后其他承包商或项目生产类似的双块式轨枕提供经验借鉴。  相似文献   
110.
通过对欧洲列车时刻表等相关数据的统计和分析,总结欧洲主要类型高速列车基于路网节点系统的行车组织特点及规律,包括列车开行方案中的列车起迄点选择、停站方案设计、列车之间的接续和换乘、直达与中转换乘方案结合方式、时刻表结构和高速列车下线运行方式等,并结合我国实际路情提出建议方案,欧洲的一些先进的设计理念对我国未来快速客运网中高速列车的行车组织方案的研究具有借鉴意义.  相似文献   
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