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IMPACT MODEL RESOLUTION ON PAINLEVE’S PARADOX 总被引:1,自引:0,他引:1
Painlevé‘s paradox is one of the basic difficulties for solving LCP of dynamic systems subjected to unilateral constraints. A bi-nonlinear parameterized impact model, consistent with dynamic principles and experimental results, is established on the localized and quasi-static impact model theory. Numerical simulations are carried out on the dynamic motion of Painlevé‘s example. The results confirm ““““impact without collision““““ in the inconsistent states of the system. A ““““critical normal force““““ which brings an important effect on the future movement of the system in the indeterminate states is found. After the motion pattern for the impact process is obtained from numerical results, a rule of the velocity‘s jump that incorporates the tangential impact process is deduced by using an approximate impulse theory and the coefficient of restitution defined by Stronge. The results of the jump rule are quite precise if the system rigidity is big enough. 相似文献
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在全球不确定性日益加剧背景下,本文阐释了经济政策不确定性、汇率与国际资本流动之间的互动机制,并进行实证研究。根据初步检验结果,构建多类包括非线性结构和异方差性质的VAR模型,并通过贝叶斯模型比较准则选取TVP-SV-VAR模型进行分析。实证结果表明:汇率变动冲击对国际资本流动存在显著的即时传导影响,但国际资本流动对汇率的传导则相对较弱。人民币贬值会显著增加我国经济政策不确定性,而经济政策不确定性增加会反过来在短期内引起人民币有升值之势。此外,经济政策不确定性增加对国际资本流入的影响较突出。2012年后,经济政策不确定性对汇率和国际资本流动的冲击效果均明显强化。 相似文献
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机器人在完成其规划动作时,常可能要通过其运动链的奇点,这时求解其运动学逆问题的通用算法遇到本质的困难,本文给出了一种算法,它可以成功地克服这个困难。文中还给出了计算实例。 相似文献
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离心场中纵向悬臂梁的大范围分岔分析 总被引:2,自引:0,他引:2
采用打靶法研究了离心场中纵向悬臂梁的大范围失稳与分岔问题。分析结果证实:随着参数a(离心臂长与梁长之比)的变化,梁平衡解可能发生三种分岔现象。文中给出了平衡解的分岔形态,并发现了梁分岔解的单向跳跃现象,即突变现象。 相似文献
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一类三种群捕食模型的正解 总被引:1,自引:0,他引:1
该文研究了在齐次Dirichlet边界条件下带有扩散的三种群捕食模型. 应用局部分支和全局分支理论, 作者给出模型正解的存在性, 稳定性, 惟一性或多解性结果. 相似文献
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Sliding state stepping algorithm for solving impact problems of multi-rigid-body system with joint friction 总被引:1,自引:0,他引:1
Impact dynamics of multi-rigid-body systems with joint friction is considered. Based on the traditional approximate assumption dealing with impact problem,a general numerical method called the sliding state stepping algorithm is introduced.This method can avoid difficulties in solving differential equations with variable scale and its result can avoid energy inconsistency before and after impact from considering complexily of tangential sliding mode.An example is given to describe details using this algorithm. 相似文献
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以滚盘实际运动为基础,按照产生约束的力学条件,建立符合实际的动力学模型;利用数值模拟检验理论结果,并解决了滚盘倒地过程中所出现的奇异问题;得到与实际非常接近的解. 相似文献