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221.
根据体上矩阵研究的新近进展,本文给出了任意体上的矩阵力方程的解判别定理及其通解的显式表示,并给出了(1)的一种有实用价值的简便解法。 相似文献
222.
To include the pointfree case, the notion of a Cauchy map easily extends as the condition that the preimage of any regular Cauchy filter contains a regular Cauchy filter. This extension, however, can be unsatisfactory if the regular Cauchy filters are scarce or non-existent, making the condition too weak, indeed sometimes even void. In this paper a variant of the notion, independent on the existence of any kind of filters, is studied: a homomorphism is called fully Cauchy if it lifts to the completions. This is generally stronger than, and in the spatial and metric cases it coincides with the previously mentioned property. Moreover, it is stable under localization. 相似文献
223.
L.F. Escudero 《European Journal of Operational Research》1984,17(3):401-414
We present an algorithm for super-scale linearly constrained nonlinear programming (LCNP) based on Newton's method. In large-scale programming solving the Newton equation at each iteration can be expensive and may not be justified when far from a local solution. For super-scale problems, the truncated Newton method (where an inaccurate solution is computed by using the conjugate-gradient method) is recommended; a diagonal BFGS preconditioning of the gradient is used, so that the number of iterations to solve the equation is reduced. The procedure for updating that preconditioning is described for LCNP when the set of active constraints or the partition of basic, superbasic and nonbasic (structural) variables have been changed. 相似文献
224.
Nistor D. Miron N. D. Surpateanu G. G. Azzouz A. 《Journal of Thermal Analysis and Calorimetry》2004,76(3):913-920
The present work tries to emphasize the effect of acid/basis properties of montmorillonite type clays by ion exchange with
cations of different natures. The acidity and basicity measuring was made by thermo programated desorption (TPD)1,2, using
ammonia like basis agent and carbon dioxide like acid agent. With TPD method we can determine acid/basis proprietes by measuring
of the quantity of the ammonia and carbon dioxide termodesorbed. Clays are crystalline aluminosilicates, similar with the
zeolyts, who presents the property of ion exchanging. That propriety can be applicated for pollutants cations from aquatic
solutions. Ion exchanging propriety depends of a lot of factors: the cation nature, the valence and the ionic ray of the cation
present in the impregnated solution. That's an advantage for depollution process of heavy metals by fixing of these metals
by montmorillonite structure. By using TPD metod we can obtaine a caracteristic diagram.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
225.
本文给出了变质量非完整系统相对于非惯性系的第一积分存在的条件,建立了这类系统的正则方程和变分方程,证明了由第一积分可直接构造系统的积分不变量,并给出一系列推论和一个例子. 相似文献
226.
On a Matrix Equation AX+XB=C over a Skew Field 总被引:6,自引:2,他引:4
In this paper we study a matrix equation AX BX=C (Ⅰ)over an arbitrary skew field,and give a consistency criterion of (Ⅰ) and an explicit expression of general solutions of (Ⅰ).A convenient,simple and practical method of solving (Ⅰ) is also given.As a particular case,we also give a simple method of finding a system of fundamental solutions of a homogeneous system of right linear equations over a skew field. 相似文献
227.
Amine Fawaz 《Central European Journal of Mathematics》2007,5(3):493-504
We compute the energy of conformal flows on Riemannian manifolds and we prove that conformal flows on manifolds of constant
curvature are critical if and only if they are isometric.
相似文献
228.
利用DirectDraw模块进行快速动画设计,重点对其直接操纵显存的特性和用后缓冲区实现动画中背景擦除和重绘的技巧进行探索,并结合火焰字的实例说明本文提出的方法是Win95下开发动画软件的一种切实可行的方法. 相似文献
229.
Synthesis of cordierite gels was performed using Si(OC2H5)4 and aluminum and magnesium nitrates as starting materials under basic conditions. Further heat treatment yields the successive
crystallisation of μ and α-cordierites and of some amounts of spinel as a secondary phase as revealed by X-ray diffraction.
The poor final densification (84% of the theoretical value) of samples obtained from the as-prepared powders has been improved
by ball-milling to values up to 95–98% of the theoretical value, the spinel proportion being simultaneously decreased. 相似文献
230.
Bin Meng Maozheng Guo Xiaohong Cao 《Proceedings of the American Mathematical Society》2005,133(10):3087-3096
We introduce the operator-valued free Fisher information for a random variable in an operator-valued noncommutative probability space and point out its relations to the amalgamated freeness. Using M. Frank and D. Larson's modular frame notion we can construct the conjugate variable for an operator-valued semicircle variable with conditional expectation covariance. Then we obtain its free Fisher information and show it is equal to the index of the conditional expectation. At last the conjugate variable with respect to a modular frame operator for a semicircle variable is also constructed.