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971.
Albert Compta Josep Ferrer Marta Peña 《Mathematical Methods in the Applied Sciences》2011,34(3):309-314
Given ?? an (A,B)‐invariant subspace, we prove that the set of friend feedbacks is a linear variety, which can be considered as the direct sum of the feedbacks of the restriction to ?? and the co‐restriction to ??⊥. In particular, when the natural controllability hypothesis hold, both pole assignments are simultaneously possible by means of a convenient friend feedback. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
972.
Alfredo Burrieza Inmaculada P. de Guzmán Emilio Muñoz‐Velasco 《Mathematical Logic Quarterly》2010,56(1):89-102
In previous works, we presented a modification of the usual possible world semantics by introducing an independent temporal structure in each world and using accessibility functions to represent the relation among them. Different properties ofthe accessibility functions (being injective, surjective, increasing, etc.) have been considered and axiomatic systems (called functional) which define these properties have been given. Only a few ofthese systems have been proved tobe complete. The aim ofthis paper is to make a progress in the study ofcompleteness for functional systems. For this end, we use indexes as names for temporal flows and give new proofs of completeness. Specifically, we focus our attention on the system which defines injectivity, because the system which defines this property without using indexes was proved to be incomplete in previous works. The only system considered which remains incomplete is the one which defines surjectivity, even ifwe consider a sequence ofnatural extensions ofthe previous one (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
973.
Katarzyna Białas 《PAMM》2010,10(1):357-358
The major objective of this study is to show how to carry out the process of structural and parametrical synthesis that is understood as a method intended to seek for the structure and parameters of a discrete model of the system with active suppression of vibrations. Active components are implemented as mechanical components with kinematic excitations. The other objective is to analyze how the active subsystem interacts with the overall investigated structure. (© 2010 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
974.
D.S. Almeida Júnior M.L. Santos J.E. Muñoz Rivera 《Mathematical Methods in the Applied Sciences》2013,36(14):1965-1976
In this paper, we consider the Timoshenko systems with frictional dissipation working only on the vertical displacement. We prove that the system is exponentially stable if and only if the wave speeds are the same. On the contrary, we show that the Timoshenko systems is polynomially stable giving the optimal decay rate. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
975.
René Meziat Tomáš Roubíček Diego Patiño 《Numerical Functional Analysis & Optimization》2013,34(4):460-488
976.
977.
F. Balibrea Gallego J.L. García Guirao J.I. Muñoz Casado 《Journal of Difference Equations and Applications》2013,19(3-4):289-304
We consider Sturm–Liouville eigenvalue problems of second order with arbitary seperated boundary conditions and perform a suitabl discretization of them. The obtained discrete Sturm–Liouville eigenvalue problems are examined and the asymptotic behavior of their eigenvalue as the norm of the partition tends to zero is investigated. 相似文献
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