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91.
Christine Böckmann 《Journal of Computational and Applied Mathematics》1996,70(2):207-224
A modification of the trust-region Gauss-Newton method for the identification of physical spectra is described and analysed. Local convergence results are presented. 相似文献
92.
93.
U. G. Abdullaev 《Applied Mathematics Letters》1994,7(6):85-89
We consider the nonlinear parabolic equation ut = (k(u)ux)x + b(u)x, where u = u(x, t, x ε R1, t > 0; k(u) ≥ 0, b(u) ≥ 0 are continuous functions as u ≥ 0, b (0) = 0; k, b > 0 as u > 0. At t = 0 nonnegative, continuous and bounded initial value is prescribed. The boundary condition u(0, t) = Ψ(t) is supposed to be unbounded as t → +∞. In this paper, sufficient conditions for space localization of unbounded boundary perturbations are found. For instance, we show that nonlinear equation ut = (unux)x + (uβ)x, n ≥ 0, β >; n + 1, exhibits the phenomenon of “inner boundedness,” for arbitrary unbounded boundary perturbations. 相似文献
94.
Bergman空间上Toeplitz算子的局部化 总被引:2,自引:0,他引:2
Bergman空间上Toeplitz算子的局部化@孙善利@卢玉峰... 相似文献
95.
Michele Cook 《Compositio Mathematica》1998,111(2):221-244
In this paper we will give necessary conditions for a Borel-fixed monomial ideal to be the generic initial ideal of a reduced, irreducible, non-degenerate curve in P3. 相似文献
96.
This article solves the problem of finding a set of group decisions that satisfy the classical Pareto unanimity principle for the case of initial data represented as fuzzy relations of individual preference. The solution proceeds from results obtained in studying the structure of convex (in the sense defined here) sets and their convex hulls. In the first part that study is carried out for spaces of arbitrary fuzzy binary relations. 相似文献
97.
During electric polarization charge is injected into the material. The structure is decorated with space charge and during the subsequent heating an apparent peak and the genuine peaks that are related to dipole randomization and charge detrapping are observed. The method is used here to analyze the molecular movements in polyimide in the temperature range from 293 to 623 K. Two weak relaxations have been observed around 337 K and around 402 K. The electrical conductivity changes with temperature in agreement with the Arrhenius law only below (W = (0.84 ± 0.03) eV ) and above ( W = (0.82 ± 0.03) eV) the temperature range where the β relaxation is observed. The variation of the electrical conductivity with temperature, in the range of the β relaxation, is controlled by the variation of the charge currier mobility with temperature and it shows a non-Arrhenius behavior. We suggest that the β1 sub-glass relaxation is related to the rotation or oscillation of phenyl groups and the β2 sub-glass relaxation is related to the rotation or oscillation of the imidic ring. At higher temperatures an apparent peak was observed. The relaxation time of the trapped charge, at 573 K, is high than 8895 s. 相似文献
98.
99.
Xian ZHANG 《数学学报(英文版)》2006,22(3):873-878
Suppose F is a field different from F2, the field with two elements. Let Mn(F) and Sn(F) be the space of n × n full matrices and the space of n ×n symmetric matrices over F, respectively. For any G1, G2 ∈ {Sn(F), Mn(F)}, we say that a linear map f from G1 to G2 is inverse-preserving if f(X)^-1 = f(X^-1) for every invertible X ∈ G1. Let L (G1, G2) denote the set of all inverse-preserving linear maps from G1 to G2. In this paper the sets .L(Sn(F),Mn(F)), L(Sn(F),Sn(F)), L (Mn(F),Mn(F)) and L(Mn (F), Sn (F)) are characterized. 相似文献
100.
Various theories of Quantum Gravity predict modifications of the Heisenberg Uncertainty Principle near the Planck scale to a so-called Generalized Uncertainty Principle (GUP). In some recent papers, we showed that the GUP gives rise to corrections to the Schrödinger equation, which in turn affect all quantum mechanical Hamiltonians. In particular, by applying it to a particle in a one-dimensional box, we showed that the box length must be quantized in terms of a fundamental length (which could be the Planck length), which we interpreted as a signal of fundamental discreteness of space itself. In this Letter, we extend the above results to a relativistic particle in a rectangular as well as a spherical box, by solving the GUP-corrected Klein–Gordon and Dirac equations, and for the latter, to two and three dimensions. We again arrive at quantization of box length, area and volume and an indication of the fundamentally grainy nature of space. We discuss possible implications. 相似文献