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951.
952.
V.H. CORTÍNEZM.T. PIOVAN 《Journal of sound and vibration》2002,258(4):701-723
In this paper, a theoretical model is developed for the dynamic analysis of composite thin-walled beams with open or closed cross-sections. The present model incorporates, in a full form, the shear flexibility (bending and warping shear) as well as a state of initial stresses. This allows to study the free vibration and buckling problems in a unified fashion. An analytical solution of the developed equations is obtained for the case of simply supported thin-walled beams. Numerical examples are given to demonstrate the importance of the shear flexibility on the vibration and buckling behavior of the considered structures. 相似文献
953.
954.
955.
We present a design technique of retarders suitable for nonlinear optical systems. A thin sample of LiNbO3 crystal is utilized as a retarder for wide-ranging applications. Analysis shows that the same crystal can be used for single-wave or two-wave retardations, changing the orientation of the crystal only. As an application, the retarder is used to polarize two waves orthogonal, as necessary for difference frequency mixing in an AgGaSe2 crystal. 相似文献
956.
谷超豪 《中国科学A辑(英文版)》2002,45(6)
The Darboux transformations for soliton equations are applied to the Yang-Mills-Higgs equations.New solutions can be obtained from a known one via universal and purely algebraic formulas. SU(N) soliton solutions are constructed with explicit formulas. The interaction of solitons is described by the splitting theorem:each p-soliton is splitting into p single solitons asymptotically as t →±∞. 相似文献
957.
It is shown that the appearance of discrete ambiguities in the optical potential of composite particles is caused by the existence of partly Pauli-forbidden states. The given interpretation is tested in the case ofα-58Ni scattering atE α=50.2 MeV where seven different optical potentials give satisfactory agreement with experiment. 相似文献
958.
The Nambu-Jona-Lasinio model as a particular model of quark flavour dynamics is bosonized in the low-energy regime using a generalized heat kernel expansion with local mass scale. The resulting effective meson Lagrangian defines a chiral soliton model, the solutions of which show a partial restoration of chiral symmetry inside the soliton. 相似文献
959.
Imre Csiszár 《Bulletin of the Brazilian Mathematical Society》2006,37(4):453-459
A simple self-contained proof of Sanov's theorem in τ-topology is given, well suited for a first course on large deviations.
*This work was supported by the Hungarian National Foundation for Scientific Research under Grant T046376 相似文献
960.
In this paper, the nonfragile control problem for synchronization of a class of chaotic dynamical systems with controller gain variations is studied. Using the Lyapunov method and LMI (linear matrix inequality) technique, a criterion for the existence of the nonfragile controller for synchronization is derived in terms of LMI. To show the effectiveness of the proposed method, the control problem is applied to Genesio chaotic system. 相似文献