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91.
92.
Although climate change is a global problem, specific mitigation measures are frequently applied on regional or national scales only. This is the case in particular for measures to reduce the emissions of land-based transport, which is largely characterized by regional or national systems with independent infrastructure, organization, and regulation. The climate perturbations caused by regional transport emissions are small compared to those resulting from global emissions. Consequently, they can be smaller than the detection limits in global three-dimensional chemistry-climate model simulations, hampering the evaluation of the climate benefit of mitigation strategies. Hence, we developed a new approach to solve this problem. The approach is based on a combination of a detailed three-dimensional global chemistry-climate model system, aerosol-climate response functions, and a zero-dimensional climate response model. For demonstration purposes, the approach was applied to results from a transport and emission modeling suite, which was designed to quantify the present-day and possible future transport activities in Germany and the resulting emissions. The results show that, in a baseline scenario, German transport emissions result in an increase in global mean surface temperature of the order of 0.01 K during the 21st century. This effect is dominated by the CO2 emissions, in contrast to the impact of global transport emissions, where non-CO2 species make a larger relative contribution to transport-induced climate change than in the case of German emissions. Our new approach is ready for operational use to evaluate the climate benefit of mitigation strategies to reduce the impact of transport emissions. 相似文献
93.
区域轨道交通与城市轨道交通衔接模式 总被引:3,自引:2,他引:1
简要阐述区域轨道交通和城市轨道交通的基本概念,在分析区域轨道交通和城市轨道交通技术特征的基础上,提出都市圈的区域城市铁路发展模式,以及区域轨道交通与城市轨道交通的衔接模式.以重庆1h经济圈的轨道交通布局为例,探讨1 h经济圈城市铁路与城市轨道交通的衔接方案. 相似文献
94.
京津冀区域轨道交通信号系统设计关键点及新技术应用研究 总被引:1,自引:1,他引:0
《铁道标准设计通讯》2015,(12):94-98
为理清京津翼一体化前期规划和研究阶段信号系统建设思路,重点研究设计关键点及新技术。通过分析京津冀区域轨道信号系统应用现状,对区域不同轨道交通模式信号应用技术比较,从互联互通需求、运营功能需求和技术融合需求三方面出发,提出系统制式选择注重兼容性、运营需求引导技术创新和注重技术融合及国产化应用等设计应重点关注问题,并对列车自动运行、车地通信和北斗卫星导航等应用新技术进行分析展望。 相似文献
95.
市域铁路两种牵引供电制式工程投资对比分析 总被引:1,自引:0,他引:1
曾志长 《铁路工程造价管理》2013,28(5):9-13
随着城市化和城镇化进程的加快及区域经济发展实力的增强,市域铁路建设进入轨道交通行列。在市域铁路工程建设中,牵引供电系统是采用25 kV交流供电制,还是采用750 V或1 500 V直流供电制,其选择直接影响到工程项目的建设规模、技术和建设标准、网络资源共享和工程投资。此文在分析交、直流供电制式主要技术特点的基础上,就选择交、直流供电制式的关键因素进行论述,并以工程实例对2种供电制式的工程投资进行分析与对比。从工程投资来说,市域铁路采用高架敷设方式,交流供电制式节省投资;采用地下敷设方式,直流供电制式节省投资。 相似文献
96.
夏绍兵 《武汉船舶职业技术学院学报》2007,6(6):57-60
我国的高职旅游教材目前尚处在摸索建设阶段,基本上没有摆脱本科教材的窠臼,没有形成高职教育特色。本文以高职《旅游概论》为例,从教材的编写体例、结构方式、内容选择等方面探讨了高职旅游教材应有的特色。 相似文献
97.
《铁道标准设计通讯》2016,(3):117-123
结合历史地域文化,从城市文脉的角度出发对宝鸡南站站房进行建筑创作,根据地形地貌的特点设计车站、广场、城市的空间接驳;创造性地引入"全程模数化设计"理念进行建筑细部推敲;以安全、舒适、经济、可行性高为原则进行消防性能化研究及建筑、结构、水、暖、电等各相关专业的设计。宝鸡南站建成后成为了交通便捷的宝鸡市地标性建筑。 相似文献
98.
“十五”期间,在铁路跨越式发展的形势下,全国地方铁路工作取得突出成绩,在地方铁路建设和满足铁路运输需求方面发挥了重要作用。按照铁路“十一五”发展规划的总体思路,地方铁路将加强行业管理力度,结合铁道部与各省、市、自治区签订的铁路建设纪要和地方铁路建设的需求,配合铁路干线的规划搞好地方铁路的规划和建设,促进区域经济的发展。2006年,地方铁路将转变发展观念,创新发展模式,提高发展质量,建立更适应地方铁路的建设模式和运营模式。 相似文献
99.
Andreas Thiel 《Coastal management》2013,41(2):144-164
Water and land use have changed dramatically over the last thirty years in Southern European coastal zones. For climatic and economic reasons coastal tourism development is often accompanied by simultaneous intensification of agricultural activity. The literature highlights a number of emerging resource pressures. The intensity of land use, excessive infrastructure development, and overexploitation of water resources pose the primary problems. Unsustainable development is often ascribed to mal-performing institutions (e.g., environmental management and land use planning), but there is a lack of studies analyzing the way in which institutions contribute to the problem. We address this gap by devising an analytical strategy that combines function analysis with the analysis of governance structures, property rights, and actors. This strategy is applied to the analysis of changes in ecosystem functions of the Portuguese coastal zone of the Algarve between the mid-eighties and today. Based on the analysis we call for an improvement of the performance of formal institutions in the Algarve. Actors in charge of implementing reformed institutions have to be given the financial and human means to implement formal property rights. Furthermore, entitlements for resource exploitation and interconnected transactions should not anymore be taken for granted. Specifically, institutions to control land use should be made more effective and incentives, that exclusively promote development, such as the construction tax, need to be questioned. 相似文献
100.
CHRISTOPHER HARTY 《Coastal management》2013,41(4):405-415
Estuarine habitats of southeast Australia have been undergoing changes characterized by a reduction of saltmarsh and an increase of mangroves. Incorporated into these changes have been mangrove migration into saltmarsh areas, thus contributing to the latter's decline. At the same time, rapid and extensive change in the catchments of many estuaries has occurred as a result of urban and rural development. It has been estimated that the changes observed between mangrove and saltmarsh wetland vegetation is caused by a series of processes, including urbanization and increased population pressure, increased rainfall, increased nutrients, mangroves recolonizing previously cleared areas, engineering works and subsequent altered tidal patterns, sea-level rise, and subsidence of intertidal flats. Planning strategies are suggested that can be implemented in an integrated manner to mitigate the threats from these processes and to ensure the sustainable management of mangrove and saltmarsh wetlands. 相似文献