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排序方式: 共有2978条查询结果,搜索用时 15 毫秒
151.
We study a class of compressible non‐Newtonian fluids in one space dimension. We prove, by using iterative method, the global time existence and uniqueness of strong solutions provided that the initial data satisfy a compatibility condition and the initial density is small in its H1‐norm. The main difficulty is due to the strong nonlinearity of the system and the initial vacuum. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
152.
Pei-Sen Li 《数学学报(英文版)》2017,33(8):1021-1038
The nonlinear branching process with immigration is constructed as the pathwise unique solution of a stochastic integral equation driven by Poisson random measures. Some criteria for the regularity, recurrence, ergodicity and strong ergodicity of the process are then established. 相似文献
153.
LIU Xiang 《中国物理C(英文版)》2009,33(6)
In this talk, we briefly review the experimental status of newly observed charmed hadrons during the past years. Then we introduce the theoretical progresses on these charmed hadrons, especially our studies on the strong decays of new charmed hadrous during the past one year. 相似文献
154.
We use an iteration scheme to approximate common fixed points of nearly asymptotically nonexpansive mappings.We generalize corresponding theorems of [1] to the case of two nearly asymptotically nonexpansive mappings and those of [9] not only to a larger class of mappings but also with better rate of convergence. 相似文献
155.
研究了具有非局部时滞的扩散Nicholson苍蝇方程,其中时滞由一个定义在所有过去时间和整个一维空间区域上的积分卷积表示.当时滞核是强生成核时,根据线性链式技巧和几何奇异扰动理论,获得了小时滞时波前解的存在性. 相似文献
156.
Dariush Souri Mohammad Elahi Mohammad S. Yazdanpanah 《Central European Journal of Physics》2008,6(2):306-310
The ternary 70P2O5-10Li2MoO4-20Li2O and 70P2O5-10Na2MoO4-20Na2O glasses, prepared by the press-melt quenching technique, were studied at temperatures between 298 and 418 K for their high
dc electric field properties. For the above purpose, the effect of a strong electric field on the dc conduction of these amorphous
bulk samples was investigated using the gap-type electrode configuration. At low electric fields, the current-voltage (I — V) characteristics have a linear shape, while at high electric fields (> 103 V/cm), bulk samples show nonlinear effects (nonohmic conduction). Current-voltage curves show increasing departure from Ohm’s
law with increasing current density, leading to critical phenomena at a maximum voltage (threshold voltage), known as switching
(switch from a low-conduction state to a higher-conduction state at threshold voltage). The Pool-Frenkel high-field effect
was observed at electrical fields of about 103–104 V/cm; then the lowering factor of the potential barrier, the high frequency dielectric constant, and the refractive index
of these glasses were determined.
相似文献
157.
张跃辉 《中国科学A辑(英文版)》2002,45(6):741-748
Let A be a quasi-hereditary algebra with a strong exact Borel subalgebra. It is proved that for any standard semisimple subalgebra
T there exists an exact Borel subalgebra B of A such that T is a maximal semisimple subalgebra of B. It is shown that the
maximal length of flags of exact Borel subalgebras of A is the difference of the radium and the rank of Grothendic group of
A plus 2. The number of conjugation-classes of exact Borel subalgebras is 1 if and only if A is basic; the number is 2 if
and only if A is semisimple. For all other cases, this number is 0 or no less than 3. Furthermore, it is shown that all the
exact Borel subalgebras are idempotent-conjugate to each other, that is, for any exact Borel subalgebras B and C of A, there
exists an idempotent e of A, and an invertible element u of A, such that eBe = u-1eCeu. 相似文献
158.
Almost-Sure Results for a Class of Dependent Random Variables 总被引:17,自引:0,他引:17
The aim of this note is to establish almost-sure Marcinkiewicz-Zygmund type results for a class of random variables indexed by
d
+
—the positive d-dimensional lattice points—and having maximal coefficient of correlation strictly smaller than 1. The class of applications include filters of certain Gaussian sequences and Markov processes. 相似文献
159.
Meirong Zhang 《Proceedings of the American Mathematical Society》1999,127(2):401-407
We consider the periodic boundary value problem for the singular differential system: where , , and . The singular potential is of repulsive type in the sense that as . Under Habets-Sanchez's strong force condition on at the origin, the existence results, obtained by coincidence degree in this paper, have no restriction on the damping forces . Meanwhile, some quadratic growth of the restoring potentials at infinity is allowed.
160.
In this paper, we consider several constructions which from a given B-product *
B
lead to another one
We shall be interested in finding what algebraic properties of the ring
are shared also by the ring
. In particular, for some constructions the rings R
B and
will be isomorphic and therefore have the same algebraic properties. 相似文献