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71.
Recently a classification of contactly-nonequivalent three-dimensional linearly degenerate equations of the second order was presented by E.V. Ferapontov and J. Moss. The equations are Lax-integrable. In our paper we prove that all these equations are connected with each other by appropriate Bäcklund transformations. 相似文献
72.
A. I. Shtern 《Russian Journal of Mathematical Physics》2018,25(2):239-240
The irreducible locally bounded finite-dimensional pseudorepresentations of connected locally compact groups are described. 相似文献
73.
《Advances in Mathematics》2013,232(1):295-310
In this paper we give an extension of the Cartier–Gabriel–Kostant structure theorem to Hopf algebroids. 相似文献
74.
《Wave Motion》2017
The phenomenon of extraordinary acoustic transmission ( eat) in a resonator, which has recently been investigated experimentally, is studied theoretically. It is shown that the combination of a single propagating mode and a symmetry orthogonal to the direction of propagation for a resonator leads to eat. This is accomplished by decomposing the problem using symmetry, the Blaschke product and the properties of functions of a single complex variable which have modulus one on the real axis. The conditions of a resonator requires that the solution has singularities in the analytic extension to complex frequencies (resonances) and it is precisely near these resonances that we observe eat. The condition of a Blaschke product requires that there is a zero at the complex conjugate of the singularity and eat occurs when the solution on the real axis passes between these complex conjugate pairs of poles and zeros. A detailed numerical study of the problem is conducted and we show that once the single mode of propagation or the symmetry is broken then eat (at least perfect transmission) no longer holds generally. 相似文献
75.
Xiao-Jun Yang H.M. Srivastava Ji-Huan He Dumitru Baleanu 《Physics letters. A》2013,377(28-30):1696-1700
In this Letter, we propose to use the Cantor-type cylindrical-coordinate method in order to investigate a family of local fractional differential operators on Cantor sets. Some testing examples are given to illustrate the capability of the proposed method for the heat-conduction equation on a Cantor set and the damped wave equation in fractal strings. It is seen to be a powerful tool to convert differential equations on Cantor sets from Cantorian-coordinate systems to Cantor-type cylindrical-coordinate systems. 相似文献
76.
V. P. Maslov 《Russian Journal of Mathematical Physics》2012,19(3):317-323
In the paper, the problem of Bose condensation into the zero energy of particles is investigated using methods of number theory. 相似文献
77.
《Communications in Nonlinear Science & Numerical Simulation》2014,19(5):1465-1473
This paper presents a study of multi-objective optimal design of full state feedback controls. The goal of the design is to minimize several conflicting performance objective functions at the same time. The simple cell mapping method with a hybrid algorithm is used to find the multi-objective optimal design solutions. The multi-objective optimal design comes in a set of gains representing various compromises of the control system. Examples of regulation and tracking controls are presented to validate the control design. 相似文献
78.
Mechanical problems involving an interphase between two well-defined, and eventually different, materials are of interest. The aim of this paper is to present a simplified model that, for low frequency regime, is appropriate for this situation: an interface model with elastic and inertial properties. We present, together with the equations of motion, an identification procedure that is valid for any mass density profile along the thickness of the interphase. For evaluating the accuracy of the model, computations of the reflection coefficients in some relevant cases are shown. Besides, a finite element method is used as a benchmark for both the high and low frequency regimes. It is worth to be noted that the numerical test has been inspired by the problem of the interphase that is formed at the bone-implant boundary. 相似文献
79.
In this paper we present the solution to a problem of recovering a rather arbitrary integral operator based on incomplete information with error. We apply the main result to obtain optimal methods of recovery and compute the optimal error for the solutions to certain integral equations as well as boundary and initial value problems for various PDE’s. 相似文献
80.
Er-Qian Rong 《Applicable analysis》2013,92(1-4):79-89
Further discussions are made on equivalence of variational inequalities with Wiener—Hopf equations especially with Toeplitz equations. equivalent propositions are given. Starting from the results, variational method for solving Toeplitz equation is considered and several applications of Toeplitz equation on space crack and contact problems are also discussed. 相似文献