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ZHANGLINGHAI 《高校应用数学学报(英文版)》1994,9(1):45-53
We study the Cauchy problem for a nonlinear evolution system with singularintegral differential terms, By means of some a priori estimates of the solution and the Leray-Schander‘s fixed point theorem, we prove the existence and the uniqueness theorems of the generalized global solution of the mentioned problem. 相似文献
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Prof. Dr. Ing. F. Buckens 《Archive of Applied Mechanics (Ingenieur Archiv)》1963,32(5):341-346
Conclusion We have seen that if the trajectory (absolute or relative) described by a point of a linkage can be duplicated by a different linkage (even when the difference is only geometrical), the parallel action of both mechanisms results in a redundant linkage, as far as the number of degrees of freedom is concerned. Admissible changes of the lengths of certain bars, or adequate removal of bars or hinges, while reducing this redundancy, may lead to equivalent and sometimes more useful linkages.As an example, this principle may be applied to Hart's four-link inverser, which first duplicated, then simplified, leads either to Peaucellier's six-bar inversor, or to a more general and apparently new six-link inversor which also can be used as a pantograph.The research reported in this paper has been sponsored by Air Force Office of Scientific Research, OAR through the European Office, Aerospace Research, United States Air Force. 相似文献
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同宿及异宿轨线的研究近况 总被引:1,自引:0,他引:1
The bifurcation near a homoclinc orbit or a heteroclinic orbit has been interesting thenathematicians in recent years. This paper surveys the recent advance in the research onthis topic from four aspects; I. the existence of the homoclinic orbits and the heteroclinc。rbits; II. the stability of a homoclinc cycle or a heteroclinic cycle; III. the mutual positionbetween the stable manifold and the unstable manifold of a saddle point; IV。 the bifur-cation of a homoclinc orbit or a heteroclinic orbit. We especially survey some important results obtained by Russian and Chinese mathematicians. Some research dircections and problems are suggested for further study. 相似文献
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建立了弱耗散非线性浅水波方程的局部适定性,对于不同的初始值,我们分别得到了解的整体存在性和解的爆破。 相似文献
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本文在任意Banach空间中研究了Lipschitz φ-半压缩映象与φ-强拟增生映象的带误差项的Ishikawa迭代过程,使用新的分析技巧建立了几个强收敛定理. 相似文献
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本文建立了多夹层壳体小应变状态下的中转动二阶大挠度的理论,接着进行适当的简化,获得了中转动、中小转动的一阶大挠度的理论. 相似文献
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关于湍流理论中的不封闭性的讨论* 总被引:1,自引:1,他引:0
有一种观点认为湍流的不封闭性是由于N-S方程的非线性,这是一似是而非的错误说法。因为工程上要求的量并不仅仅限于湍流的平均速度和平均压力,即使方程式是线性的,也无法把工程上要求的这些量逐个求出来。本文论证了湍流的不封闭性来源于目前的湍流理论中缺少了一个与实际情况符合的有关分布函数,并且进一步说明了湍流模式理论的局限性和用N-S方程直接计算机模拟亦是相当困难的原因。 相似文献