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211.
铁路运输作为我国交通系统的重要组成部分,对我国经济的发展具有重要的促进作用。在经济发展的不同阶段,对铁路运输的需求也不同。铁路运输的规模和速度要能够满足经济发展的需要,而且铁路运输系统的管理、结构等方面的发展水平也要与经济发展水平相适应。 相似文献
212.
阐述了单电站三种电力网络、两电站两种电力网络和多电站三种电力网络的设计原理和技术特点,分析不同电力网络形式对舰船电力系统生命力和可靠性的影响;以几种典型电力网络方案为例,计算各电力网络结构的供电概率,提供舰船电力系统网络设计建议。 相似文献
213.
J. P. DOODY 《Coastal management》2013,41(2):163-173
This article presents the results of the Thematic Study on "the role of information in delivering Integrated Coastal Zone Management (ICZM) in Europe." It provides a definition of information and discusses the need for, and nature of, information as it influences and supports ICZM. The conclusions from the study are summarized, highlighting the importance of viewing information provision as part of the process of developing effective ICZM. The results of InfoCoast '99, a symposium held in February 1999 on knowledge and information for coastal management, are discussed and some of the practical steps that have and can be taken to meet the information need for ICZM in Europe are considered. 相似文献
214.
Angeliki Pardali Evangelos Kounoupas Iasonas Lainos 《Maritime Policy and Management》2013,40(6):706-719
ABSTRACTFurther to being Greece’s biggest port, Piraeus has been a traditional pole of attraction for a plethora of organisations, companies, and institutions engaged in port- and shipping-related activities. Regional development literature has already indicated that the benefits deriving from adjacency and agglomeration economies are maximised when individual entities are organised in forming business clusters. Therefore, the paper critically addresses the existence of theoretical preconditions to a competitive port–maritime cluster formulation in wider Piraeus area. Based on a thorough review of cluster theory, the basic characteristics of clusters are identified to provide the analytical tools for examining the geographical concentration and economic specialisation in Piraeus. Field research in the form of in-depth interviews with leading shipping- and port-related business representatives and institutional bodies and the analysis of qualitative and quantitative data collected revealed that necessary preconditions for successful cluster formulation are met despite the inexistence of a formally recognised cluster. Two distinct poles of economic activity (shipping and port related) are recognised, demonstrating differentiated clustering behaviours and patterns of interaction with other players. The paper concludes with proposals deriving from this dual cluster structure and governance and the need for innovative, differentiated strategies. 相似文献
215.
William S. Fisher Deborah N. Vivian Jed Campbell Charles Lobue Rebecca L. Hemmer Sherry Wilkinson 《Coastal management》2013,41(5):429-452
AbstractStates and other jurisdictions may protect coral reefs using biological water quality standards outlined by the United States Clean Water Act (CWA). Such protection will require long-term, regional monitoring of the resource using biological indicators and a probability-based sampling design. A 60-station survey targeting nearshore linear coral reef was conducted across southern Puerto Rico in December 2011 to document the status of reef inhabitants using a probabilistic, regional sampling design. The quantity, type and condition of stony corals, fish, gorgonians, and sponges were documented from each station, providing a robust representation of linear reef status and composition across the region. Fish represented 106 unique taxa and stony corals 32 unique taxa. Benthic organisms (stony corals, sponges, and gorgonians) averaged nearly 12 colonies per square meter, more than half of which were gorgonians. Assessment results can be used as a baseline to compare with future regional surveys to quantify change in reef condition over time (trend). Both temporal and spatial changes can be expected after large-scale disturbances like hurricanes Maria and Irma in 2017. The indicators and probabilistic sampling design support the long-term regional monitoring envisioned by the Environmental Protection Agency to implement CWA protections in Puerto Rico and elsewhere. 相似文献
216.
为识别区域综合交通系统能耗驱动因子,测算其对系统能耗的贡献度,将驱动因素分为规模效应、结构效应和技术效应,采用ASIF数据构造原理和时序列回归法识别各因子的相关性,运用迪氏分解方法建立扩展LMDI分解模型,计算各因子能耗贡献度.计算表明,规模效应和技术效应的影响程度在逐渐减弱,结构效应的影响程度在逐渐增加;运输结构还需要进一步优化,对系统能耗的影响还有很大下降空间;近年来能耗效率已经得到很大提高,但能耗效率对能耗的贡献正在逐渐减弱,未来提高运输强度对降低能耗有明显效果.经实证检验,计算模型可靠、结论可信,能为区域综合低碳交通政策制定提供更科学的依据. 相似文献
217.
通过协整分析并建立误差修正模型探讨浙江省经济发展与交通运输发展间短期和长期的均衡关系,并在此基础上通过Granger因果分析探讨浙江省经济发展与交通运输发展间的因果关系。得出浙江省经济发展与交通运输发展间存在长期均衡关系,浙江省经济的增长与交通运输发展间存在着正相关关系的结论。实践证明,浙江省经济的增长在一定程度上推动交通运输的发展。 相似文献
218.
摘要高职教育专业设置与区域产业结构相匹配,是发展高等职业教育的必须选择,也是区域经济社会发展的迫切需要。 相似文献
219.
王厦 《南通航运职业技术学院学报》2013,(4):64-67
文章介绍了沪通铁路的基本情况,分析了南通物流经济发展现状,并在此基础上阐述了沪通铁路的建成通车对南通物流经济发展所产生的影响。 相似文献
220.