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151.
太湖流域水灾害应急对策研究 总被引:1,自引:0,他引:1
太湖流域是我国经济社会高度发达的地区之一,发生水灾害时往往会造成重大经济损失。对发生各类水灾害时的应急对策展开研究总结,以减轻水灾害,避免人员伤亡,保障经济社会可持续健康稳定发展,并通过分析典型案例的实际应对过程,为今后开展类似工作提供参考。 相似文献
152.
文章对新线路启动中LFX-912收发信机频繁发信现象进行分析,找出了具体原因,逐步处理,消除了频繁发信现象,并提出防范措施和详细处理步骤。 相似文献
153.
Abstract: The artificial neural networks(ANN) , which have broad application, are proposed to develop Cu-Pb composite plates materials. Based on the back propagation(BP) algorithm of the forward muhilayer perceptron, the model to predict the shear stress under different ingredient of the third element and the hot dipping temperature for Cu-Pb composite plates are established. Then the relational model among the third element, hot dipping temperature and shear stress by using the limited data are studied, and the forecast average error is 4%. This model can satisfy the requirements of the precision of forecast in the project experiment process. The results show that the corresponding shear stress is greater when the third element in the element contains more Sn; the most appropriate temperature of hot-dip plating about is 340℃, 'after predicted with lead/the third element/the best performance of copper composite material element of the third group is the one-element Sn, hot dip plating temperature is 335 ℃ ; two-element is 90% Sn 10% Bi, and hot dip plating temperature is 345 ℃. The prediction results can be used for a reference in instructing the further experimental design. 相似文献
154.
针对一类范数有界和具有外界干扰的状态不可测的线性系统,提出了一种根据观测器的鲁棒保性能控制器的设计方法.通过利用Lyapunov稳定性原理和H∞理论,可以得出鲁棒保性能控制器存在的一个充分条件.所设计的控制器不仅能保证闭环系统的稳定性,而且也能保证闭环系统具有一定的线性二次性能指标和H∞性能指标.利用仿真研究,得出所提方法的有效性. 相似文献
155.
An accurate closed form solution is proposed to estimate camera pose by several mirrored reference object images acquired via a planar mirror under different unknown poses. Compared with state-of-the-art methods, our method is more accurate when there are more than three images and has explicit geometric meanings. This method also properly handles cases in which some of the mirror poses are parallel. The central idea is to minimize an error metric based on all reflections of rotation, which enables the camera rotation to be estimated directly by SVD of sum of mirrored camera rotations. After that, the camera translation is computed by solving a large system of linear equations to minimize object space collinearity error. Both synthesized data and real data experiments show the advantages of our approach. 相似文献
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159.
The effect of microstructural changes on the ductile-brittle transition temperature (DBTT) was studied in a titanium-getter ed Fe-8Ni-2 Mn-0.15 Ti alloy. A fairly strong grain size dependence of the transition temperature, 8°C/mm?1/2, was found. Grain size refinement from 38 μm (ASTM #6.5) to 1.5 μm (ASTM #15.5) through a four-step thermal treatment lowered the transition temperature by 162°C. A small amount of retained austenite was introduced into this grain-refined microstructure, and the transition temperature was reduced by an additional 120 ~ 150°C. The reduction of the DBTT due to retained austenite was smaller when the austenite was in a large-grained structure (64°C). The distribution and stability of retained austenite were also studied. 相似文献
160.
The dispersion of nanosilica that was modified and original in organic solvents could be judged directly by using methyl red
as the indicator, and the principle of color development was also discussed. A method has been developed for the determination
of the acidity of solid surfaces, which consists of titration of the solid suspended in benzene with n-butyl amine, using neutral red as the indicator. Basic indicator forms a red color on acidic solids, and the end-point of
the titration is the disappearance of the red color.
The text was submitted by the authors in English. 相似文献