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51.
52.
张卫国 《数学物理学报(A辑)》2003,23(6):679-691
该文通过适当代换并结合假设待定法,求出了具高阶非线性项的Liénard方程a″(ξ)+la(ξ)+ma\+\{2p+1\}(ξ)+na\+\{4p+1\}(ξ)=0的三类精确解. 据此求出了广义Ginzburg Landau方程、Rangwala Rao方程及若干 导数schr〖AKo¨D〗dinger型方程的孤波解和三角函数型周期波解. 相似文献
53.
A. Aizpuru F.J. Pérez-Fernández 《Journal of Mathematical Analysis and Applications》2003,284(1):89-96
Several classical results on uniform convergence of unconditionally Cauchy series are generalized to weakly unconditionally Cauchy series. This uniform convergence is characterized through subalgebras and subfamilies of . A generalization of the Orlicz-Pettis theorem is also proved by mean of subalgebras of . 相似文献
54.
S. Yassemi 《Acta Mathematica Hungarica》2001,92(3):179-183
Let R be a (not necessarily Noetherian) commutative ring and let M be a (not necessarily finitely generated) R-module. We characterize the modules with only finitely many weakly associated primes as those modules M admitting a chain 0 = M
0 M
1 ... M
n
= M of submodules together with prime ideals p1, p2,...,p
n
such that the set of weakly associated primes of M
i
/M
i-1 is equal to {p
i
} for all 1 i n. Let M = gra(M) =
n0a
n
M/a
n+1
M be the corresponding graded module over the graded ring R = gra(R) =
n0a
n
/a
n+1. It is shown that the union of the set of weakly associated primes of..... 相似文献
55.
Let X be a Banach space with a weak uniform normal structure and C a non–empty convexweakly compact subset of X. Under some suitable restriction, we prove that every asymptoticallyregular semigroup T = {T(t) : t ∈¸ S} of selfmappings on C satisfying
has a common fixed point, where WCS(X) is the weakly convergent sequence coefficient of X, and\({\left| {{\left\| {T(t)} \right\|}} \right|}\) is the exact Lipschitz constant of T(t). 相似文献
${\mathop {\lim \inf }\limits_{S \mathrel\backepsilon t \to \infty } }{\left| {{\left\| {T(t)} \right\|}} \right|} < {\text{WCS}}(X)$
56.
多目标规划弱较多有效解的充要条件 总被引:2,自引:0,他引:2
本文构造欧氏空间上的一个连续泛函,建立关于非凸锥H的分离定理,给出多目标规划弱较多有效解的充要条件. 相似文献
57.
Regularity Results for the
Generalized Beltrami System 总被引:1,自引:0,他引:1
Abstract
For the generalized Beltrami system with two
characteristic matrices, we deal with the regularity of its very
weak solutions in the Sobolev class
(1 <
r <
n). By changing the
generalized Beltrami system into a class of a divergent elliptic
system with nonhomogeneous items, we obtain that each of its
very weak solutions is essentially a classical weak solution of
a usual Sobolev class. Furthermore, we also establish a higher
regularity of its weak solution if the regularity hypotheses of
two characteristic matrices are improved.
Supported by the National Natural Science Foundation
of China (49805005) and by the research foundation of Northern
Jiaotong University (2002SM061) 相似文献
58.
We introduce a microacoustic sensor, which combines the quartz crystal microbalance, a liquid-filled cavity and an intermediate artificial layer with effective acoustic properties. Each of the three components fulfils a specific task. The quartz vibrates in its thickness shear mode and acts as source and detector of shear waves, which penetrate the intermediate artificial layer and excite a resonance in the liquid-filled cavity. Both the piezoelectric transducer and the liquid-filled cavity are high-Q resonators with well-adjusted resonance frequencies very close to each other. The intermediate artificial layer couples the two resonators in a distinct manner via control of the propagation of acoustic waves between the quartz crystal and the liquid-filled cavity layer. The origin of the sensor signal is a change of the resonance frequency of the liquid-filled cavity caused by variations of acoustic properties of the liquid analyte inside the cavity, first of all speed of sound. This resonance appears as second resonance peak in the admittance spectrum of the quartz crystal. 相似文献
59.
60.
Eva M. Mazcuñán-Navarro 《Journal of Mathematical Analysis and Applications》2008,337(1):197-218
In this paper we establish lower bounds for the weakly convergent sequence coefficient WCS(X) of a Banach space X, in terms of some well known moduli and coefficients. By mean of these bounds we identify several properties, of geometrical nature, which imply normal structure. We show that these properties are strictly more general than other previously known sufficient conditions for normal structure. 相似文献