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991.
基于旋转薄壳理论, 采用求积元法, 建立了求积元法求解环壳问题的单元列式, 并对圆环壳、椭圆环壳的静力及自由振动问题进行了分析. 数值算例与精确解及有限元结果相对比, 证明了求积元法分析此类连续环壳问题的准确和高效性. 同时, 分析结果表明, 椭圆环壳长短轴的比值k对壳体的受力特性及求积元法的收敛率有显著的影响. 相似文献
992.
Fuzheng Gao & Xiaoshen Wang 《计算数学(英文版)》2015,33(3):307-322
For Sobolev equation, we present a new numerical scheme based on a modified weak Galerkin finite element method, in which differential operators are approximated by weak forms through the usual integration by parts. In particular, the numerical method allows the use of discontinuous finite element functions and arbitrary shape of element. Optimal order error estimates in discrete $H^1$ and $L^2$ norms are established for the corresponding modified weak Galerkin finite element solutions. Finally, some numerical results are given to verify theoretical results. 相似文献
993.
We study the problem of the approximation in law of the Rosenblatt sheet. We prove the convergence in law of two families of process to the Rosenblatt sheet: the first one is constructed from a Poisson process in the plane and the second one is based on random walks. 相似文献
994.
一类广义Boussinesq方程的整体弱解和整体弱吸引子 总被引:1,自引:0,他引:1
本文证明了一类广义Boussinesq方程的整体弱解和整体弱吸引子的存在性。 相似文献
995.
?. Kuru 《Annals of Physics》2009,324(12):2548-264
The dynamical algebras of the trigonometric and hyperbolic symmetric Pöschl-Teller Hamiltonian hierarchies are obtained. A kind of discrete-differential realizations of these algebras are found which are isomorphic to so(3, 2) Lie algebras. In order to get them, first the relation between ladder and factor operators is investigated. In particular, the action of the ladder operators on normalized eigenfunctions is found explicitly. Then, the whole dynamical algebras are generated in a straightforward way. 相似文献
996.
Electromagnetic fields are quantized in a manifestly covariant way by means of a class of reducible “center-of-mass N-representations” of the algebra of canonical commutation relations (CCR). The four-potential A
a
(x) transforms in these representations as a Hermitian four-vector field in Minkowski four-position space (without change of
gauge), but in momentum space it splits into spin-1 massless photons and two massless scalars. What we call quantum optics
is the spin-1 sector of the theory. The scalar fields have physical status similar to that of dark matter (spin-1 and spin-0
particle numbers are separately conserved). There are no negative-norm or zero-norm states. Unitary dynamics is given by the
point-form interaction picture, with minimal-coupling Hamiltonian constructed from fields that are free on the null-cone boundary
of the Milne universe. SL(2,C) transformations as well as the dynamics are represented unitarily in the Hilbert space corresponding
to N four-dimensional oscillators. Vacuum is a Bose-Einstein condensate of the N-oscillator gas and is given by any N-oscillator product state annihilated by all annihilation operators. The form of A
a
(x) is determined by an analogue of the twistor equation. The same equation guarantees that the set of vacuum states is Poincaré
invariant. The formalism is tested on quantum fields produced by pointlike classical sources. Photon statistics is well defined
even for pointlike charges, with ultraviolet and infrared regularizations occurring automatically as a consequence of the
formalism. The probabilities are not Poissonian but of a Rényi type with α=1−1/N; the Shannon limit N→∞ is an ultraviolet/infrared-regularized Poisson distribution. The average number of photons occurring in Bremsstrahlung
splits into two parts: The one due to acceleration, and the one that remains nonvanishing even for inertially moving charges.
Classical Maxwell electrodynamics is reconstructed from coherent-state averaged solutions of Heisenberg equations. We show
in particular that static pointlike charges polarize vacuum and produce effective charge densities and fields whose form is
sensitive to both the choice of representation of CCR and the corresponding vacuum state. 相似文献
997.
Daniel Lehmann 《International Journal of Theoretical Physics》2009,48(1):261-281
Similarity-Projection structures abstract the numerical properties of real scalar product of rays and projections in Hilbert
spaces to provide a more general framework for Quantum Physics. They are characterized by properties that possess direct physical
meaning. They provide a formal framework that subsumes both classical Boolean logic concerned with sets and subsets and quantum
logic concerned with Hilbert space, closed subspaces and projections. They shed light on the role of the phase factors that
are central to Quantum Physics. The generalization of the notion of a self-adjoint operator to SP-structures provides a novel
notion that is free of linear algebra.
This work was partially supported by the Jean and Helene Alfassa fund for research in Artificial Intelligence. 相似文献
998.
Donggao Deng Zhongshan University China Yanchang Han South China Normal University China 《分析论及其应用》2005,21(3):280-293
Suppose μ is a Radon measure on Rd, which may be non doubling. The only condition assumed on μ is a growth condition, namely, there is a constant Co > 0 such that for all x ∈ supp(μ) and r > 0,μ(B(x,r)) ≤ Corn, where 0 < n ≤ d. We prove T1 theorem for non doubling measures with weak kernel conditions. Our approach yields new results for kernels satisfying weakened regularity conditions, while recovering previously known Tolsa's results. We also prove T1 theorem for Besov spaces on nonhomogeneous spaces with weak kernel conditions given in [7]. 相似文献
999.
1000.
A note on multilinear singular integrals with rough kernel 总被引:3,自引:0,他引:3
LanJiacheng 《分析论及其应用》2004,20(2):182-188
In this paper, the author gives the weighted weak Lipschitz boundedness with power weight for roughmultilinear integral operators. A simple way is obtained that is closely linked with a class of rough frac-tional integral operators. 相似文献