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971.
A method is presented for the solution of the parametric quadratic programming problem by the use of conjugate directions. It is based on the method for quadratic programming proposed by the author in [1].While engaged in this research the author had a part-time post with the Manpower Services Commission.  相似文献   
972.
In a recent paper [6] we suggested an algorithm for solving complicated mixed-integer quadratic programs, based on an equivalent formulation that employs a nonsingular transformation of variables. The objectives of the present paper are two. First, to present an improved version of this algorithm, which reduces substantially its computational requirements; second, to report on the results of a computational study with the revised algorithm.  相似文献   
973.
The proper phase and group speeds when quadratic finite elements are applied to the one-dimensional pure advection equation are presented and the myth of a spurious computational mode is dispelled.  相似文献   
974.
We will investigate the stability problem of the quadratic equation (1) and extend the results of Borelli and Forti, Czerwik, and Rassias. By applying this result and an improved theorem of the author, we will also prove the stability of the quadratic functional equation of Pexider type,f 1 (x +y) + f2(x -y) =f 3(x) +f 4(y), for a large class of functions.  相似文献   
975.
《代数通讯》2013,41(9):4571-4609
Abstract

We study complex structures in real two-dimensional commutative algebras and show their connection with homotopy properties of the multiplications. An application to the Riccati equation in rank three algebras is also discussed.  相似文献   
976.
A polynomial-time algorithm based on a revised method of iterative central difference limit is presented for computing the numerical value of the derivative of a given analytic function. Through numerical experiments, we establish that this algorithm is a best one. This can be used to obtain the derivative to a desired accuracy subject to the precision of the computer for violently fluctuating or rapidly oscillatory functions. The concerned time/computational complexity is so small in practice that in the non-main-frame supercomputing era when over estimated 95% of computing resources is unutilized and hence a waste, the complexity here is not an issue. We have, for the purpose of a comparison, also included Matlab symbolic-cum-numerical computation to obtain the derivative of the foregoing functions numerically. Matlab programs in both Matlab standard precision as well as Matlab variable precision are also included for the central difference limit along with the symbolic-cum-numerical computation. The reader concerned with computing the derivative of an ill-conditioned function - large or small - can use these programs by copying, pasting, and executing and can readily check the quality of the derivative.  相似文献   
977.
We give the first example of a quadratic map having a phase transition after the first zero of the geometric pressure function. This implies that several dimension spectra and large deviation rate functions associated to this map are not (expected to be) real analytic, in contrast to the uniformly hyperbolic case. The quadratic map we study has a non-recurrent critical point, so it is non-uniformly hyperbolic in a strong sense.  相似文献   
978.
具有二个焦点的二次系统极限环的分布与个数   总被引:6,自引:0,他引:6       下载免费PDF全文
张平光 《数学学报》2001,44(1):37-44
本文证明了具有二个焦点的二次系统必在其中一个焦点外围至多有一个极限环这一猜想.从而得到具有二个焦点的二次系统之极限环必是(O,i)或(1,i)分布(i= 0, 1, 2,).  相似文献   
979.
郭学军  宋光天 《数学学报》2005,48(2):403-406
本文给出了一种计算数域Tame核的方法.应用到虚二次域上,证明了当 Nv>8δD6时,(?)t/:K2S'F/K2SF→k*是双射。  相似文献   
980.
         下载免费PDF全文
We study Pfister neighbors and their characterization over fields of characteristic , where we include the case of singular forms. We give a somewhat simplified proof of a theorem of Fitzgerald which provides a criterion for when a nonsingular quadratic form is similar to a Pfister form in terms of the hyperbolicity of this form over the function field of a form which is dominated by . From this, we derive an analogue in characteristic of a result by Knebusch saying that, in characteristic , a form is a Pfister neighbor if its anisotropic part over its own function field is defined over the base field. Our result includes certain cases of singular forms, but we also give examples which show that Knebusch's result generally fails in characteristic for singular forms. As an application, we characterize certain forms of height in the sense of Knebusch whose quasi-linear parts are of small dimension. We also develop some of the basics of a theory of totally singular quadratic forms. This is used to give a new interpretation of the notion of the height of a standard splitting tower as introduced by the second author in an earlier paper.

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