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951.
本文将Sobolev空间中的Clarkson不等式的几个引理作了适当的推广,并给出了证明. 相似文献
952.
R-linear convergence of the Barzilai and Borwein gradient method 总被引:4,自引:0,他引:4
Combined with non-monotone line search, the Barzilai and Borwein(BB) gradient method has been successfully extended for solvingunconstrained optimization problems and is competitive withconjugate gradient methods. In this paper, we establish theR-linear convergence of the BB method for any-dimensional stronglyconvex quadratics. One corollary of this result is that theBB method is also locally R-linear convergent for general objectivefunctions, and hence the stepsize in the BB method will alwaysbe accepted by the non-monotone line search when the iterateis close to the solution. 相似文献
953.
定义了汉语的分段语法,并根据自然语言的分段循环结构,提出了汉语的分段循环分析策略.它的基本思想是确定语言的一组基本范畴,其相应的句法规则段及其之间的优先关系,对于每一个句法规则段,分别依次采用改进的Kilbury算法、它的优点在于分析过程中的项目集比较小,而且避免了无用分析树的产生,从而大大提高了分析效率. 相似文献
954.
We show that the set of stationary weak solutions for a class of infinite dimensional stochastic differential equations coincides
with the set of shift invariant, space-time Gibbs fields for a certain potential. The key step consists in proving the Gibbs
variational principle for space-time Gibbs fields.
Received: 20 May 1999 / Revised version: 14 May 2001 / Published online: 11 December 2001 相似文献
955.
自锁模Cr:LiSAF激光器的实验研究 总被引:2,自引:1,他引:1
以功率为900mW,波长为488nm的单线氩离子激光作为泵浦源,在腔内不加任何主动调制器和可饱和吸收体的情况下实现了Cr:LiSAF激光器的飞秒级自锁模运转,得到了脉冲宽度为40fs,重复频率为100MHz,平均输出功率为45mW的稳定的锁模脉冲序列。 相似文献
956.
In this paper a theory of modal analysis for the dynamic response of fluid-structure systems is presented. A pair of generalized eigenvalue equations with three real symmetric matrices and their relationships are derived from the finite element equations in the form of structural displacements and fluid velocity potential. Generalized orthogonality relations of modal vectors are then developed. The response of the system to external excitation is derived in closed form by modal expansion. Two examples of the solution are given for illustration. 相似文献
957.
Enzyme activity of commercial glucose oxidase was enhanced after purification through a strong anionic exchange resin. In order to get a better insight into this phenomenon, surface pressure–area (π–A) isotherms and surface pressure–time (π–t) isotherms was used to study the interaction and the absorption at different pH values of the subphases between octadecylamine and glucose oxidase purified by a styrene system quaternary ammonium type strongly basic anionic exchange resin. Circular dichroism (CD), electrophoresis and enzyme activity measurements were conducted to study these phenomena. A preliminary hypothesis has been suggested to explain why the enzyme activity of purified glucose oxidase was higher than that of the commercial one. 相似文献
958.
Nonvolatile holographic recording is performed with green light in LiNbO3:Ce:Cu crystals. The refractiveindex change and the recording sensitivity are times better than those obtained by recording with red light,and higher optical fixing efficiency is obtained. Correspondingly, theoretical investigations are given. 相似文献
959.
960.
Dai Longxiang 《数学学报(英文版)》1994,10(1):42-48
In this paper, we consider the related weighted boundedness of the operators which were studied by J. Duoandikotxea and J.
L. Rubio de Francia. 相似文献