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101.
Micha Rzeczkowski 《Mathematische Nachrichten》2021,294(1):118-131
In the paper we prove that the Nevanlinna counting function and the Carleson function of analytic self‐maps of finitely connected domains with smooth boundary are equivalent. Using this result we obtain the characterization of compact composition operators on Hardy–Orlicz spaces. 相似文献
102.
Ge DONG 《数学年刊B辑(英文版)》2021,42(3):333-356
In this paper, the author studies the existence of the minimal nonnegative solutions of some elliptic variational inequalities in Orlicz-Sobolev spaces on bounded or unbounded domains. She gets some comparison results between different solutions as tools to pass to the limit in the problems and to show the existence of the minimal solutions of the variational inequalities on bounded domains or unbounded domains. In both cases,coercive and noncoercive operators are handled. The sufficient and necessary conditions for the existence of the minimal nonnegative solution of the noncoercive variational inequality on bounded domains are established. 相似文献
103.
In this paper we report synthesis of phase-pure highly resistive magnetoelectric BiFeO3 thin films on Pt/TiO2/SiO2/Si substrate by using pulsed laser deposition technique. For the first time saturated ferroelectric hysteresis loop has been
observed. It has confirmed the presence of ferroelectricity in BiFeO3 compound. The films exhibit dielectric anomaly near Neel temperature. This anomaly is related to the influence of vanishing
magnetic order on the electric order. In situ domain alignment occurs during observation of the films under transmission electron microscope. 相似文献
104.
105.
D.P.A. Hardwick S.L. Naylor S. Bujkiewicz T.M. Fromhold D. Fowler A. Patan L. Eaves A.A. Krokhin P.B. Wilkinson M. Henini F.W. Sheard 《Physica E: Low-dimensional Systems and Nanostructures》2006,32(1-2):285
We study the effects of inter-miniband electron tunneling and electric field domains on the current–voltage and conductance–voltage curves of biased semiconductor superlattices under the action of a magnetic field that is tilted relative to the plane of the layers. For this geometry, electrons in the superlattice minibands exhibit a unique type of stochastic semiclassical motion. At certain critical values of the electric field within the superlattice layers, the stochastic trajectories change abruptly from fully localized to completely unbounded, and map out an intricate web-like mesh of conduction channels in phase space. Delocalization of the electron paths produces a series of strong resonant peaks in the electron drift velocity versus electric field curves. We use these drift velocity characteristics to make self-consistent drift-diffusion calculations of the current–voltage and differential conductance–voltage curves of the superlattices, which reveal strong resonant features originating from the sudden delocalization of the stochastic single-electron paths. We show that this delocalization has a pronounced effect on the distribution of space charge and electric field domains within the superlattices. Inter-miniband tunneling greatly reduces the amount of space-charge buildup, thus enhancing the domain structure and both the strength and number of the current resonances. 相似文献
106.
高进寿 《数学年刊A辑(中文版)》2006,(3)
设Ω是C~n中具有光滑边界的有限型m的凸域,本文的主要结果是把Gleason问题在加权Bergman空间的情形推广到Ω. 相似文献
107.
We consider a periodically heterogeneous and perforated medium
filling an open domain Ω of ℝN. Assuming that the size of the periodicity of the structure and of the holes is O(ε),
we study the asymptotic behavior, as ε → 0, of the
solution of an elliptic boundary value problem with strongly oscillating coefficients posed in Ωε
(Ωε being Ω minus the holes) with a Neumann condition on the boundary of the holes. We use Bloch wave
decomposition to introduce an approximation of the solution in the
energy norm which can be computed from the homogenized solution
and the first Bloch eigenfunction. We first consider the case
where Ωis ℝN and then localize the problem for a
bounded domain Ω, considering a homogeneous Dirichlet
condition on the boundary of Ω. 相似文献
108.
本文利用频率分析对角化的方法,研究了三维拟线性热弹性力学方程区域内部解的奇性传播规律. 首先从微局部观点出发,利用仿微分算子和拟微分算子将方程仿线性化和对角化.然后,利用穿梭法和经典的双曲方程和抛物方程理论,证明了区域内部解的奇性传播也是沿耦合方程组的双曲算子的零次特征带传播,并且当初值的奇性沿方程组的双曲算子的前向光锥传播时,时间t也具有很好的正则性. 相似文献
109.
Sharp estimates of the point-evaluation functional in weighted Bergman spaces L
p
a
(Ω, dν
α) and for the point-evaluation derivalive functional in Besov spaces B
p
(Ω) are obtained for bounded symmetric domains Ω in ℂ
n
.
Received October 25, 1999, Accepted December 6, 2000 相似文献
110.
首先证明了正三角形的外接椭圆中面积最小的是一个圆.进而用初等方法证明了二维情形的F.John定理. 相似文献