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71.
S. Tomasiello 《Nonlinear dynamics》2007,50(1-2):37-48
In this paper, the nonlinear planar response of a hinged–hinged buckled beam to a primary-resonance excitation of its first
vibration mode is computed by a new numerical scheme. The beam is subjected to an axial force beyond the critical load of
the first buckling mode and to a transverse harmonic excitation. The nonlinear dynamical problem is solved by deducing directly
the discretized equations governing the problem thanks to a new approach, here called DQ based approach, since it is based
on the application of the quadrature rules of the DQM. As it will be shown, for the problem here considered, the minimum number
of degrees of freedom to be retained to limit the numerical errors is four. Computer simulations of the dynamic behaviour
of the discretized system are conducted by means of the IDQ method, a method proposed and recently generalized by the author.
A sequence of supercritical period-doubling bifurcations leading to chaos, snapthrough motions and quasi-periodic motions
can be observed, similarly to some cases existing in literature. 相似文献
72.
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74.
Boris S. Mordukhovich Bingwu Wang 《Journal of Mathematical Analysis and Applications》2003,282(1):63-84
In this paper we study some properties of sets, set-valued mappings, and extended-real-valued functions unified under the name of “sequential normal compactness.” These properties automatically hold in finite-dimensional spaces, while they play a major role in infinite-dimensional variational analysis. In particular, they are essential for calculus rules involving generalized differential constructions, for stability and metric regularity results and their broad applications, for necessary optimality conditions in constrained optimization and optimal control, etc. This paper contains principal results ensuring the preservation of sequential normal compactness properties under various operations over sets, set-valued mappings, and functions. 相似文献
75.
本文研究了完全检验的质量控制问题,将广泛用于X-控制图的AT&T准则应用于完全检验,并根据完全检验的特点,提出一种新的最优模型,数值实验结果表明AT&T准则下的完全检验优于传统的完全检验。 相似文献
76.
Jörg Waldvogel 《BIT Numerical Mathematics》2006,46(1):195-202
We present an elegant algorithm for stably and quickly generating the weights of Fejér’s quadrature rules and of the Clenshaw–Curtis
rule. The weights for an arbitrary number of nodes are obtained as the discrete Fourier transform of an explicitly defined
vector of rational or algebraic numbers. Since these rules have the capability of forming nested families, some of them have
gained renewed interest in connection with quadrature over multi-dimensional regions.
AMS subject classification (2000) 65D32, 65T20, 65Y20 相似文献
77.
We review two methods discussed in the literature to determine the effective parameters of strongly interacting particles
as they move through a heat bath. The first one is the general method of chiral perturbation theory, which may be readily
applied to this problem. The other is the method of thermal QCD sum rules. We show that, when the spectral sides of the sum
rules are calculated correctly, they do not lead to any new results, but reproduce those of the vacuum sum rules. 相似文献
78.
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80.
Ivona R. Radović Mirjana Lj. KijevčaninEmila M. Djordjević Bojan D. DjordjevićSlobodan P. Šerbanović 《Fluid Phase Equilibria》2008
The densities of binary mixtures of (1-propanol, or 1-butanol, or 2-butanol, or 1-pentanol + chlorobenzene) have been measured at temperatures 288.15, 293.15, 298.15, 303.15, 308.15 and 313.15 K and atmospheric pressure while for the system (2-methyl-2-propanol + chlorobenzene) measurements were performed at the same pressure and temperatures 303.15, 308.15, 313.15, 318.15 and 323.15 K. All measurements were performed by means of an Anton Paar DMA 5000 digital vibrating-tube densimeter. Excess molar volumes VE were determined and fitted by the Redlich–Kister equation. It was observed that in all cases, VE increase with rising of temperature. The values of limiting excess partial molar volumes have been calculated, as well. The obtained results have been analysed in terms of specific molecular interactions present in these mixtures taking into consideration effect of the chain length of alcohols, degree of branching in the chain, relative position of the alkyl and OH group in an alcohol and the effect of temperature on them. In addition, the correlation of VE binary data was performed with the Peng–Robinson–Stryjek–Vera cubic equation of state (PRSV CEOS) coupled with the van der Waals (vdW1) and CEOS/GE mixing rule introduced by Twu, Coon, Bluck and Tilton (TCBT). Also, the possibility of cross prediction between VE and VLE by means of the NRTL parameters of GE model available in literature and those incorporated in the TCBT model was tested. 相似文献