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971.
分析国内现有的3种典型的信号交叉口通行能力计算方法,阐述有序加权平均算子理论及其赋权方法,以信号交叉口的通行能力为决策因子,建立了一种信号交叉口通行能力优化算法。通过对南京市某一信号交叉口进行实际调查并进行通行能力计算,结果表明:经有序加权平均算子理论综合加权优化后的信号交叉口通行能力与传统计算方法相比,具有更高的精度。 相似文献
972.
973.
在弹塑性理论的基础上,考虑了材料性能随温度的变化,应用J2流动理论导出了高温下钢筋混凝土构件弹塑性增量本构模型,编制了该模型的有限元求解程序.该模型具有明确的物理意义,表达形式规范,便于数值手段实现.数值计算结果与现有的试验模型基本吻合. 相似文献
974.
975.
Numerical study of ice-induced loads on ship hulls 总被引:1,自引:0,他引:1
A numerical model is introduced in this paper to investigate both global and local ice loads on ship hulls. This model is partly based on empirical data, by which the observed phenomena of continuous icebreaking can be well reproduced. In the simulation of a full-scale icebreaking trial, the interdependence between the ice load and the ship’s motion is considered, and the three degree-of-freedom rigid body equations of surge, sway and yaw are solved by numerical integration. The variations in the level ice thickness and in the strength properties of ice can also be taken into account. The simulated ice loads on ship hulls are discussed through two case studies, in which the ship’s performance, the statistics of ice-induced frame loads, and the spatial distribution of ice loads around the hull are analyzed and compared with field measurements. As far as we know the present paper is the first to integrate all the features above. It is hoped that further studies on this numerical model can supplement the field and laboratory measurements in establishing a design basis for the ice-going ships especially for ships navigating in the first-year ice. 相似文献
976.
977.
Assessing the impact of characteristics of the built environment on travel behavior can yield valuable tools for land use
and transportation planning. Of particular interest are planning models that can estimate the effects of ‘smart growth’ planning.
In this paper, a post-processor method of quantifying and searching for relationships among many aspects of travel behavior
and the built environment is developed and applied to the Buffalo, NY area. A wide scope of travel behavior is examined, and
over 50 variables, many of which are based on high-detail data sources, are examined for potentially quantifying the built
environment. Linear modeling is then used to relate travel behavior and the built environment, and the resulting models may
be applied in a post-processor fashion to travel models to provide some measure of sensitivity to built environment modifications.
The study’s findings demonstrate that mode choice is highly correlated to measures of the built environment, and that many
of the principles of smart growth appear to be a valid way to encourage non-vehicle travel. Home-based VHT and VMT appear
to be affected by the built environment to a lesser degree. 相似文献
978.
979.
基于Mindlin问题的位移解导出了拉拔荷载作用下砂浆锚杆的剪应力分布和轴力分布的弹性解。依托岢临高速公路某黄土隧道,通过现场试验得出边墙系统锚杆的极限拉拔力,分析了拉拔荷载作用下边墙系统锚杆的受力特性;探讨了不同土体性质下砂浆锚杆剪应力及轴力的分布形式。研究成果为黄土隧道系统锚杆的设计和优化提供了理论依据,对设计和施工具有指导意义。 相似文献
980.