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991.
992.
为获取五河口斜拉桥超长大直径工程桩的极限承载力值,对2根直径2.5m桩长95m的工程桩,采用桩基静栽试验自平衡法单、双荷载箱技术进行试桩研究,为最终确定桥墩桩基础设计提供了直观的参考依据。该试桩方法适合特大型桥梁桩基施工场地小、试验时间短、试桩荷载大的要求,试桩经注浆补强工艺后可作工程桩应用。 相似文献
993.
城乡公交统筹发展策略研究 总被引:10,自引:0,他引:10
在阐述我国城乡公交统筹发展必要性的基础上,着重分析了目前城乡客运体系发展差距的症结所在,解析城乡公交统筹发展的内涵,以管理体制、政策法规、站场设施、市场建设4个方面的统筹为切入点,探讨了我国城乡公交统筹发展的具体策略。 相似文献
994.
文章回顾了“十五”期间我国交通科技的发展,提出交通科技发展的战略选择与“十一五”应重点关注的若干问题。 相似文献
995.
通过对福建省福鼎宁德段高速公路声环境现状的调查研究,采用类比分析的方法,确定其沿线所要保护的声环境敏感点,合理科学预测交通噪声对声环境的影响,提出减轻噪声污染的若干措施。 相似文献
996.
桥梁维修加固中粘贴钢板的造价分析 总被引:1,自引:0,他引:1
粘贴钢板是目前广西桥梁维修加同中的常用方法,此方法能充分利用旧桥,降低工程造价,并能尽快恢复通行。文章通过对粘贴钢板的工、料、机、价格构成分析,探讨如何编制补充定额计算粘贴钢板的造价。 相似文献
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Antti Talvitie 《Transportation》2006,33(1):83-110
The paper describes an approach to the vexing problem of transport planning and policy. It deals jointly with three questions, which in today's practice are addressed separately: How are hypotheses about transport problems and alternatives to their solution developed? How can a good plan or policy be identified? What is the process of implementing a transport plan or policy? In doing this the paper has the ambitious objective of proposing a new model and process for transport planning and policy. It is applicable in developed and developing countries and is not restricted to the transport sector. The paper builds on, and is a reinterpretation of two cornerstone transport planning and decision-making models – the CATS (Chicago Area Transportation Study) Planning and Design Model and Braybrooke and Lindblom's Disjointed Incrementalism. It advances a technique of experiential incrementalism (termed polisanalysis) to develop and implement plans and policies. It proposes that problems should be diagnosed by observation and continuous data collection; that their continuous analysis, finding the “cure”, and implementation take place through the method of experiential incrementalism. In this method interventions are grounded on the theories of neoinstitutional economics and psychoanalysis and derived using contact function, explained in the paper, which renders the method scientific replicability. Experiential incrementalism can employ a wider array of options in planning and policy than is presently thought possible. Like other scientific methods, its application requires rigorous training. 相似文献
1000.
T. A. Wenzel K. J. Burnham M. V. Blundell R. A. Williams 《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2006,44(2):153-171
The article demonstrates the implementation of a model-based vehicle estimator, which can be used for combined estimation of vehicle states and parameters. The estimator is realised using the dual extended Kalman filter (DEKF) technique, which makes use of two Kalman filters running in parallel, thus 'splitting' the state and parameter estimation problems. Note that the two problems cannot be entirely separated due to their inherent interdependencies. This technique provides several advantages, such as the possibility to switch off the parameter estimator, once a sufficiently good set of estimates has been obtained. The estimator is based on a four-wheel vehicle model with four degrees of freedom, which accommodates the dominant modes only, and is designed to make use of several interchangeable tyre models. The paper demonstrates the appropriateness of the DEKF. Results to date indicate that this is an effective approach, which is considered to be of potential benefit to the automotive industry. 相似文献