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991.
C. Zhang 《Mathematische Nachrichten》2009,282(9):1342-1353
Let S be a Riemann sphere with n ≥ 4 points deleted. In this article we investigate certain filling closed geodesics of S and give quantitative common lower bounds for the hyperbolic lengths of those geodesics with respect to any hyperbolic structure on S (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
992.
We study the existence result of solutions for the nonlinear degenerated elliptic problem of the form, -div(a(x, u,△↓u)) = F in Ω, where Ω is a bounded domain of R^N, N≥2, a :Ω×R×R^N→R^N is a Carathéodory function satisfying the natural growth condition and the coercivity condition, but they verify only the large monotonicity. The second term F belongs to W^-1,p′(Ω, w^*). The existence result is proved by using the L^1-version of Minty's lemma. 相似文献
993.
Xue-mei Hu Zhi-zhong Wang Feng Liu 《应用数学学报(英文版)》2008,24(1):99-116
This paper studies estimation and serial correlation test of a semiparametric varying-coefficient partially linear EV model of the form Y = X^Tβ +Z^Tα(T) +ε,ξ = X + η with the identifying condition E[(ε,η^T)^T] =0, Cov[(ε,η^T)^T] = σ^2Ip+1. The estimators of interested regression parameters /3 , and the model error variance σ2, as well as the nonparametric components α(T), are constructed. Under some regular conditions, we show that the estimators of the unknown vector β and the unknown parameter σ2 are strongly consistent and asymptotically normal and that the estimator of α(T) achieves the optimal strong convergence rate of the usual nonparametric regression. Based on these estimators and asymptotic properties, we propose the VN,p test statistic and empirical log-likelihood ratio statistic for testing serial correlation in the model. The proposed statistics are shown to have asymptotic normal or chi-square distributions under the null hypothesis of no serial correlation. Some simulation studies are conducted to illustrate the finite sample performance of the proposed tests. 相似文献
994.
综合评价方法广泛应用于教育、管理等很多领域.在一定程度上可以说综合评价的结果是决策的基础.因此选用好的综合评价方法非常重要.提出了一种新的综合评价方法:平均值组合评价方法.这种方法在一定程度上克服了单一综合评价方法的片面性.研究结果还表明所提的平均值组合评价方法在平方损失函数和兼容度两种标准下具有优良性. 相似文献
995.
在α和q满足适当的条件下,当初值属于Fourier-Herz空间?q1-2α(R3)时,我们建立了广义3维不可压旋转Navier-Stokes方程温和解的整体适定性和解析性.作为推论,我们也给出了广义Navier-Stokes方程的相应结论. 相似文献
996.
一种新的消色像全息术 总被引:3,自引:2,他引:1
本文从全息再现像的物像关系出发,对准像面情况下,像点随波长及参考光源扩展的变化进行了研究.阐明了利用散射线光源作参考光使全可见光范围内的像叠加在一起,产生消色像全息图的基本思想,并引入了消色像域的概念.考虑到点基元全息图尺寸及人眼瞳孔对成像光束的限制,白光再现时,可以获得清晰、明亮、具有一定景深和相当视场范围的消色再现像. 相似文献
997.
We consider a trace theorem for self-similar Dirichlet forms on self-similar sets to self-similar subsets. In particular, we characterize the trace of the domains of Dirichlet forms on Sierpinski gaskets and Sierpinski carpets to their boundaries, where the boundaries are represented by triangles and squares that confine the gaskets and the carpets. As an application, we construct diffusion processes on a collection of fractals called fractal fields. These processes behave as an appropriate fractal diffusion within each fractal component of the field. 相似文献
998.
V. Marraffa 《Czechoslovak Mathematical Journal》2006,56(2):475-490
The McShane and Kurzweil-Henstock integrals for functions taking values in a locally convex space are defined and the relations
with other integrals are studied. A characterization of locally convex spaces in which Henstock Lemma holds is given. 相似文献
999.
In this paper, we propose a design method of guaranteed cost controllers for uncertain large-scale systems with time delays in subsystem interconnections using delayed feedback. Using the Lyapunov method, a linear matrix inequality (LMI) optimization problem is formulated to design a delayed feedback controller which minimizes the upper bound of a given quadratic cost function. A numerical example is included to illustrate the design procedures.Communicated by Q. C. ZhaoThe authors thank the Associate Editor and three anonymous referees for careful reading and useful suggestions. 相似文献
1000.
Magnetization relaxation of uniaxial anisotropic ferromagnetic particles with linear reaction dynamics driven by DC/AC magnetic field 下载免费PDF全文
《中国物理 B》2021,30(9):90202-090202
The response of uniaxial anisotropic ferromagnetic particles with linear reaction dynamics subjected to alternating current(AC) or direct current(DC) bias magnetic field is evaluated by the reaction–diffusion equation for the probability distribution function of the molecular concentration in the spherical coordinate system. The magnetization function and the probability distribution function of the magnetic particles in the reaction system are derived by using the Legendre polynomials and Laplace transform. We discuss the characteristics of magnetization and probability distribution of the magnetic particles with different anisotropic parameters driven by a DC and AC magnetic fields, respectively. It is shown that both the magnetization and the probability distribution decrease with time increasing due to the reaction process. The uniformity of the probability distribution and the amplitude of the magnetization are both affected by the anisotropic parameters.Meanwhile, the difference between the case with linear reaction dynamics and the non-reaction case is discussed. 相似文献