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961.
Yu. F. Dolgii E. V. Ul’yanov 《Proceedings of the Steklov Institute of Mathematics》2007,259(2):S95-S110
To obtain sufficient conditions for the asymptotic stability of linear periodic systems with fixed delay commensurable with the period of coefficients, singular numbers of the monodromy operator are used. To find these numbers, a self-adjoint boundary value problem for ordinary differential equations is applied. We study the motion of eigenvalues of this boundary value problem under a variation of a parameter. Obtaining sufficient conditions for the asymptotic stability is reduced to finding the bifurcation value of the parameter for the boundary value problem. 相似文献
962.
V. A. Gorelov 《Journal of Mathematical Sciences》2007,146(2):5649-5654
In the paper, we prove that two definitions of E-functions present in mathematics are equivalent if E-functions satisfy second-order linear differential equations. For this set of functions, a weakened variant of the well-known
Siegel conjecture about representability of any E-function by a polynomial of hypergeometric functions is also proved.
__________
Translated from Fundamentalnaya i Prikladnaya Matematika, Vol. 11, No. 6, pp. 33–39, 2005. 相似文献
963.
K. C. Kiwiel 《Journal of Optimization Theory and Applications》2007,134(3):549-554
We give a linear time algorithm for the continuous quadratic knapsack problem which is simpler than existing methods and competitive
in practice. Encouraging computational results are presented for large-scale problems.
The author thanks the Associate Editor and an anonymous referee for their helpful comments. 相似文献
964.
In this paper we define and study an extension of the g-Drazin for elements of a Banach algebra and for bounded linear operators based on an isolated spectral set rather than on
an isolated spectral point. We investigate salient properties of the new inverse and its continuity, and illustrate its usefulness
with an application to differential equations. Generalized Mbekhta subspaces are introduced and the corresponding extended
Mbekhta decomposition gives a characterization of circularly isolated spectral sets. 相似文献
965.
V. A. Morozov E. M. Mukhamadiev A. B. Nazimov 《Computational Mathematics and Mathematical Physics》2007,47(12):1885-1892
Regularization of singular systems of linear algebraic equations by shifts is examined. New equivalent conditions for the shift regularizability of such systems are derived. 相似文献
966.
M.C. Gonzalez-Garcia M. Maltoni 《The European Physical Journal C - Particles and Fields》2003,26(3):417-428
We study the stability of the results of the three-neutrino oscillation analysis of atmospheric and reactor neutrino data
under departures of the one dominant mass scale approximation. In order to do so we perform the analysis of atmospheric and
reactor neutrino data in terms of three-neutrino oscillations where the effect of both mass differences is explicitly considered.
We study the allowed parameter space resulting from this analysis as a function of the mass splitting hierarchy parameter which parameterizes the departure from the one dominant mass scale approximation. We consider schemes with both direct and
inverted mass ordering. Our results show that in the analysis of the atmospheric data the derived range of the largest mass
splitting, , is stable, while the allowed ranges of mixing angles and are wider than those obtained in the one dominant mass scale approximation. Inclusion of the CHOOZ reactor data in the analysis
results in the reduction of the parameter space in particular for the mixing angles. As a consequence the final allowed ranges
of the parameters from the combined analysis are only slightly broader than when obtained in the one dominant mass scale approximation.
Received: 31 May 2002 / Revised version: 10 July 2002 / Published online: 31 October 2002 相似文献
967.
968.
Ben Craps Matthias R. Gaberdiel Jeffrey A. Harvey 《Communications in Mathematical Physics》2003,234(2):229-251
We study D-branes in the bosonic closed string theory whose automorphism group is the Bimonster group (the wreath product
of the Monster simple group with ℤ2). We give a complete classification of D-branes preserving the chiral subalgebra of Monster invariants and show that they
transform in a representation of the Bimonster. Our results apply more generally to self-dual conformal field theories which
admit the action of a compact Lie group on both the left- and right-moving sectors.
Received: 20 February 2002 / Accepted: 17 August 2002 Published online: 19 December 2002
Communicated by R.H. Dijkgraaf 相似文献
969.
The influence of a large signal on the characteristics of a small signal near the frequency of the former is experimentally studied for the case of their simultaneous propagation through a resonant transmission line based on backward volume magnetostatic waves. The effects observed are caused by the excitation of spin waves in a ferromagnetic film at different large-signal frequencies and by the back influence of excited spin-wave packets on the amplitude and phase characteristics of the small signal. 相似文献
970.
For two types of qutrits specified by the dynamical symmetry SU(3) and SU(2), we consider the difference in entanglement caused by the lack of quantum observables in the latter case. In particular, we show that the SU(2) qutrits can have specific separable entanglement caused by quantum correlations of intrinsic degrees of freedom in a single party without interparty correlations. 相似文献