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本文详细地介绍了使用双点法对DSS—80型镗头回转精度的现场测试;讨论了主轴径向误差运动园图象的分析处理和评定方法。测试系统简单,实验操作方便,数据可靠。这对高精度轴系的园度误差和表面粗糙度测试具有现实意 相似文献
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Public acceptance is consistently listed as having an enormous impact on the implementation and success of a congestion charge scheme. This paper investigates public acceptance of such a scheme in Australia. Surveys were conducted in Brisbane and Melbourne, the two fastest growing Australian cities. Using an ordered logit modeling approach, the survey data including stated preferences were analyzed to pinpoint the important factors influencing people’s attitudes to a congestion charge and, in turn, to their transport mode choices. To accommodate the nature of, and to account for the resulting heterogeneity of the panel data, random effects were considered in the models. As expected, this study found that the amount of the congestion charge and the financial benefits of implementing it have a significant influence on respondents’ support for the charge and on the likelihood of their taking a bus to city areas. However, respondents’ current primary transport mode for travelling to the city areas has a more pronounced impact. Meanwhile, respondents’ perceptions of the congestion charge’s role in protecting the environment by reducing vehicle emissions, and of the extent to which the charge would mean that they travelled less frequently to the city for shopping or entertainment, also have a significant impact on their level of support for its implementation. We also found and explained notable differences across two cities. Finally, findings from this study have been fully discussed in relation to the literature. 相似文献
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宗海图中海岸线的选择与界址点的综合处理 总被引:1,自引:0,他引:1
宗海图的绘制要根据用海事实准确界定用海范围。现实往往以岸线为宗海的部分边界,因此海岸线对宗海图有重要影响,它不但能够直观的显示宗海位置,也直接影响界址点的规划选取。对于顺岸用海项目,海岸线就成为宗海图的界址线。由于海岸线具有不确定性,因此给界址点的规划带来优化的可能。文章结合具体实例,在海岸线的选取以及如何优化选取海岸线上的界址点等问题上进行了探讨。通过限制海岸线界址点上的方位角和距离两个形变参量,可以有效地简化岸线上冗余的界址点。利用EXCEL软件的公式编辑功能,能够方便快捷地实现控制形变参量的岸线界址点简化。 相似文献
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刘海宁 《兰州交通大学学报》2014,(6):161-164
研究了非突变有限生灭系统,利用系统转移速率矩阵的特殊形式,以Caley-Hamilton定理为基础,结合齐次线性递归系统的通解,获得了该系统形式简洁,计算比较封闭的幂级数形式的瞬态解,并给出了系数的确定方法,最后通过数值仿真验证了解的可靠性. 相似文献
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风能是一种优秀的绿色能源,随着风电开发延伸到海上,带有动力定位系统的风电安装船开始得到广泛应用。文章基于动力定位能力曲线对一艘风电安装船的动力定位系统进行失效分析,寻找出最危险的工况,为实际工程提供参考,以便在作业时尽量避开这些工况。 相似文献
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公路、水利、市政部门经常遇到暴雨径流计算的问题,不同业界从业者运用的计算公式不同,对于重现期的选择差别也比较大,给从业者造成了困扰。通过对不同业界暴雨径流计算异与同的分析,可知:不同业界暴雨径流的计算原理还是一致的,只是根据各自专业特点和要求,在公式形式、参数选择方面做了适应性调整。 相似文献
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从消防用水量、上水栓间距、设计暴雨重现期、集装箱冲洗用水量几个方面,对JTJ 212―2006《河港工程总体设计规范》存在的问题进行分析探讨,并提出修改建议。 相似文献