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81.
Arif Rafiq Nazir Ahmad Mir Farooq Ahmad 《应用数学和力学(英文版)》2007,28(7):901-906
In account of the famous Cebysev inequality, a rich theory has appeared in the literature. We establish some new weighted Cebysev type integral inequalities. Our proofs are of independent interest and provide new estimates on these types of inequalities. 相似文献
82.
Marius Buliga 《Journal of Elasticity》1998,52(3):201-238
83.
Singularly perturbed systems with structural perturbations are analyzed for stability. New sufficient conditions of asymptotic stability and uniform asymptotic stability are established. The systems in question are widely used in control theory, engineering, etc 相似文献
84.
本文给出了求解一类相当普遍的三维运动接触问题的分析解法,并且把仅仅对静态接触问题成立的 定理推广到动力学情形,作了严格证明。作为例子,对接触区为椭圆的情形给出了积分形式的解,并且作了数值计算,由这些结果可以看出运动压体速度的效应。 相似文献
85.
CFD Calculation of Turbulent Flow with Arbitrary Wall Roughness 总被引:1,自引:0,他引:1
David Apsley 《Flow, Turbulence and Combustion》2007,78(2):153-175
86.
平面八节点四边形理性元 总被引:2,自引:0,他引:2
推导平面八节点四边形理性有限元列式,采用具有直到四次多项式的平面问题的微分方程的解作为插值函数,算例结果表明平面八节点四边形理性有限元的有效性。 相似文献
87.
88.
Florian J. Stadler Joachim Kaschta Helmut Münstedt Florian Becker Michael Buback 《Rheologica Acta》2009,48(5):479-490
Low-density polyethylenes (LDPE) were synthesized in a laboratory-scale autoclave under high pressure. These samples were
found to possess a high molar mass tail, resulting in a distinctly bimodal molar mass distribution and a lower concentration
of long-chain branching than typical of commercial LDPEs. Rheological experiments in elongation showed that these samples
exhibit a very pronounced strain hardening, which could be favorable for distinct processing operations. Although the samples
have a rather high molar mass ( g/mol), their zero shear-rate viscosities η
0 and their shear thinning behavior are still in a range, where thermoplastic processing is possible. A qualitative understanding
of the experimental results is tried by the model of the Cayley tree.
相似文献
Helmut MünstedtEmail: |
89.
K. S. Matviichuk 《International Applied Mechanics》2006,42(6):699-713
Sufficient conditions for the technical stability in measure of a nonstationary control system with variable structure are
established. The controller of the system has feedback-switched filters functioning together with shaper and actuator. It
is assumed that the nonstationary parameters of the system vary within given ranges, at a finite rate, with appropriate control
laws, with adjustment against mismatch signal, its derivatives of finite order, and all variable parameters of the filter.
The parameters of the switching hyperplane remain constant. This approach for analysis of technical stability does not involve
sliding mode conditions. Criteria of technical instability in measure for the control system under consideration are formulated
using the properties of systems of comparison from below. The general criteria of technical stability and instability are
applied to nonstationary filtered-control systems of variable structure of the third order. The comparison method based on
normalized Lyapunov functions is used
__________
Translated from Prikladnaya Mekhanika, Vol. 42, No. 6, pp. 110–127, June 2006. 相似文献
90.
Analytical solutions for cohesive zone models 总被引:2,自引:0,他引:2
Solutions are given for a cantilever beam specimen using a beam on elastic foundation model to incorporate various cohesive zone traction laws. These included both positive and negative linear slopes and constant stresses. Negative slopes give rise to multiple solutions. However, all the solutions give very similar results for energy release rate and beam root rotation confirming insensitivity to the form of the traction law. The use of these solutions to analyse peeling is discussed. 相似文献