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141.
农村基础设施投资是促进我国农村经济增长的重要推动力量,因此在农村经济建设方面,农村基础设施的建设有着举足轻重的地位。长期以来,我国农村基础设施建设相对来说比较落后,完善我国农村基础设施建设成为当前改善农村经济方面的一项重要举措。本文从农村基础设施建设对我国农村经济的影响入手,通过对农村基础设施建设各要素投入与经济产出的回归分析,得出农村基础设施投资对农村经济的增长具有很大影响,并提出相应对策与建议。 相似文献
142.
在三角波、正弦波、方波3种加载波形下对LZ50车轴钢紧凑拉伸试样开展疲劳裂纹扩展试验,采用扫描电镜观察断口形貌,并结合试验数据分析加载波形对裂纹尺寸增量和扩展速率的影响。结果显示:加载频率较高时,疲劳裂纹扩展行为对波形的敏感性较低,断口形貌基本相同;加载频率较低时,波形对疲劳裂纹扩展行为的影响增大,断口形貌出现差异;稳态扩展区以疲劳条带为主要扩展机制,三角波加载下的疲劳条带间距明显小于其他2种波形,其失稳扩展区形貌以韧窝为主,且韧窝较其他2种波形下的小且浅。同时,基于LS-DYNA软件和节点位移外推法对CT试样在3种加载波形下的应力强度因子进行计算和分析。结果表明:仿真分析波形对疲劳裂纹扩展的影响机制与试验结果基本一致。 相似文献
143.
对中国1953—2007年的铁路建设和经济增长的样本数据进行实证分析,通过单位根检验、协整检验、格兰杰因果关系检验主要步骤对数据进行分析。研究结果表明:铁路建设对我国经济增长具有正向的推动作用,并间接提升了工业化水平,但是,经济增长不是铁路建设的直接原因,是因为近年我国经济建设增长大力推动了公路航空等基础设施的发展而对于铁路建设的推动力度不够;铁路作为我国重要的基础设施一部分,铁路的发展速度关系到我国经济建设能否在我国基础设施平台上充分稳定的向前发展,因为滞后的基础设施建设对国民经济建设不利,需要加大基础设施建设投资力度特别是铁路建设以适应经济增长的需要。 相似文献
144.
欧洲机车车辆厂商的演变 总被引:1,自引:0,他引:1
介绍了近 10年来世界上主要机车车辆厂商的重组演变过程 ,着重介绍了阿尔斯通、西门子、AD tranz和庞巴迪公司经过合并重组发展成国际跨国集团的经过 ,预示着机车车辆领域的发展趋势是研发资源的集中化、生产基地的集约化和降低产品价格 相似文献
145.
随着经济的发展,机动车尾气对于城市环境的危害已是公认的事实,但就对人类健康的具体影响少见阐述,其对环境危害究竞多大的定量分析并不清晰也不多见。此文试从环境工程学角度研究对此进行剖析。根据历年经济、交通数据,分析、预测中国城市经济和机动车交通发展的现状和趋势,发现中国城市机动车交通即将进入一个高速增长的爆发期,从而造成中国城市空气污染问题恶化,轨道交通的发展可以改善这一状况,减少因城市空气污染问题恶化而造成的巨大经济损失。 相似文献
146.
Effect of transportation infrastructure on economic growth in India: The VECM approach 总被引:1,自引:0,他引:1
This paper examines the effect of transportation (road and rail) infrastructure on economic growth in India over the period 1970–2010. Using Vector Error Correction Model (VECM), the paper finds bidirectional causality between road transportation and economic growth. It also finds bidirectional causality between road transportation and capital formation, bidirectional causality between gross domestic capital formation and economic growth, unidirectional causality from rail transportation to economic growth and unidirectional causality from rail transportation to gross capital formation. The paper suggests that expansion of transport infrastructure (both road and rail) along with gross capital formation will lead to substantial growth of the Indian economy. Therefore, within its stated scope, this study suggests that a suitable transport policy should be retained to boost transportation infrastructure and hence sustainable economic growth in India. 相似文献
147.
石道华 《长沙铁道学院学报》2012,(4):116-122
根据品牌可持续成长力内涵及铁路旅客列车的特性,明确铁路旅客列车品牌可持续成长力的主要影响因素,并据此建立相应的评价指标体系,然后结合长沙一北京西Z17/18次列车、利用AHP—FCE方法对其品牌可持续成长力进行实证评估,评估结果验证了评价指标体系的科学性和全面性,最后依据评价结果,给出了针对Z17/18次列车的改进措施与建议。 相似文献
148.
针对呼和浩特市客运出租汽车行业的发展及其现状,分析了造成影响呼和浩特市客运出租汽车发展的相关因素,通过SPSS软件计算分析,找到相关性较高的五个因素并采用逐步回归分析法,建立了确定呼和浩特市客运出租汽车发展预测模型。该模型可以对呼和浩特市市区规划年份所需的客运出租汽车发展进行预测,通过该地区客运出租汽车历史实际数据和模型计算结果比较,表明该预测模型较为理想。 相似文献
149.
Do changes in neighborhood characteristics lead to changes in travel behavior? A structural equations modeling approach 总被引:3,自引:2,他引:3
Suburban sprawl has been widely criticized for its contribution to auto dependence. Numerous studies have found that residents
in suburban neighborhoods drive more and walk less than their counterparts in traditional environments. However, most studies
confirm only an association between the built environment and travel behavior, and have yet to establish the predominant underlying
causal link: whether neighborhood design independently influences travel behavior or whether preferences for travel options
affect residential choice. That is, residential self-selection may be at work. A few studies have recently addressed the influence
of self-selection. However, our understanding of the causality issue is still immature. To address this issue, this study
took into account individuals’ self-selection by employing a quasi-longitudinal design and by controlling for residential
preferences and travel attitudes. In particular, using data collected from 547 movers currently living in four traditional
neighborhoods and four suburban neighborhoods in Northern California, we developed a structural equations model to investigate
the relationships among changes in the built environment, changes in auto ownership, and changes in travel behavior. The results
provide some encouragement that land-use policies designed to put residents closer to destinations and provide them with alternative
transportation options will actually lead to less driving and more walking.
Xinyu (Jason) Cao is a research fellow in the Upper Great Plains Transportation Institute at North Dakota State University. His research interests include the influences of land use on travel and physical activity, and transportation planning. Patricia L. Mokhtarian is a professor of Civil and Environmental Engineering, Chair of the interdisciplinary Transportation Technology and Policy graduate program, and Associate Director for Education of the Institute of Transportation Studies at the University of California, Davis. She specializes in the study of travel behavior. Susan L. Handy is a professor in the Department of Environmental Science and Policy and Director of the Sustainable Transportation Center at the University of California, Davis. Her research interests center around the relationships between transportation and land use, particularly the impact of neighborhood design on travel behavior. 相似文献
Susan L. HandyEmail: |
Xinyu (Jason) Cao is a research fellow in the Upper Great Plains Transportation Institute at North Dakota State University. His research interests include the influences of land use on travel and physical activity, and transportation planning. Patricia L. Mokhtarian is a professor of Civil and Environmental Engineering, Chair of the interdisciplinary Transportation Technology and Policy graduate program, and Associate Director for Education of the Institute of Transportation Studies at the University of California, Davis. She specializes in the study of travel behavior. Susan L. Handy is a professor in the Department of Environmental Science and Policy and Director of the Sustainable Transportation Center at the University of California, Davis. Her research interests center around the relationships between transportation and land use, particularly the impact of neighborhood design on travel behavior. 相似文献
150.
分析影响交通可持续发展的因素,引入成长管理的概念,给出基于成长管理的城市交通可持续发展对策和实施成长管理需要注意的问题,并给出基于成长管理的交通可持续发展的评价指标。结合上海市交通白皮书的修编,给出基于成长管理的建议。 相似文献