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971.
常曲率空间中有限点集的两类几何不等式 总被引:1,自引:1,他引:0
应用距离几何的理论与方法,研究了n维常曲率空间中有限点集的一些几何度量之间关系,建立了常曲率空间中有限点集的两类几何不等式,推广了已有的结果. 相似文献
972.
Seven kinds of monotone maps 总被引:20,自引:0,他引:20
Known as well as new types of monotone and generalized monotone maps are considered. For gradient maps, these generalized monotonicity properties can be related to generalized convexity properties of the underlying function. In this way, pure first-order characterizations of various types of generalized convex functions are obtained. 相似文献
973.
周颂平 《浙江大学学报(理学版)》1986,(3)
1.前言 本文采用下列记号与定义: 以‖·‖p[a,b]表示[a,b]上的L~p范数,1≤P≤∞,C_([-1,1])~1是[-1,1]上有连续导函数的函数全体,C_(2π)~1是有连续导函数的以2π为周期的函数全体,记 相似文献
974.
In this paper, based on a new more general ansatz, a new algebraic method, named generalized Riccati equation rational expansion method, is devised for constructing travelling wave solutions for nonlinear evolution equations with nonlinear terms of any order. Compared with most existing tanh methods for finding travelling wave solutions, the proposed method not only recovers the results by most known algebraic methods, but also provides new and more general solutions. We choose the generalized Burgers-Fisher equation with nonlinear terms of any order to illustrate our method. As a result, we obtain several new kinds of exact solutions for the equation. This approach can also be applied to other nonlinear evolution equations with nonlinear terms of any order. 相似文献
975.
§1Introductionandpreliminaries In1929,Knaster,Kuratowski,andMazurkiewicz(simply,KKM)[1]deducedthe celebratedKKMtheorem.TheKKMtheory,firstcalledbySehiePark,isthestudyof applicationsofvariousequivalentformulationsoftheclassicalKKMprinciple[2].Atthe beginning,thetheorywasmainlystudiedonconvexsubsetsofHausdorfftopologicalvector spaces[3],butlater,ithasbeenextendedtoconvexspacesbyLassonde[4],andtospaces havingcertainfamiliesofcontractiblesubsets(simply,C-spacesorH-spaces)by Horvath[5].Mor… 相似文献
976.
This paper deals with generalized vector quasi-equilibrium problems. By virtue of a nonlinear scalarization function, the
gap functions for two classes of generalized vector quasi-equilibrium problems are obtained. Then, from an existence theorem
for a generalized quasi-equilibrium problem and a minimax inequality, existence theorems for two classes of generalized vector
quasi-equilibrium problems are established.
This research is partially supported by the Postdoctoral Fellowship Scheme of The Hong Kong Polytechnic University and the
National Natural Science Foundation of China. 相似文献
977.
978.
Dingxiong Wang 《中国科学A辑(英文版)》1997,40(8):872-878
The upper bounds on the entropy of a radiation system confined to a spherical box are calculated in six cases by using the
equation of state of radiation in flat spacetime and the equation of state of radiation near black-hole horizon, which was
derived by Li and Liu (hereafter the Li-Liu equation). It turns out that the Li-Liu equation does have unique advantage in
dealing with the entropy bound of critical self-gravitating radiation systems, while the usual equation of state will result
in entropy divergence. In the case of non-self-gravitating radiation systems and non-critical self-gravitating radiation systems,
there is no difference in the entropy bounds derived by these two equations of state. 相似文献
979.
51.IntroductionLetF=[O,1],foranya,beF,definea b=max{a,b},a*b=min{a,b}.Mn(F)standsforthesetofa1lthenthordermatrixesinF,matrixAinMn(F)iscalledFuzzymatrixA.Letrbeanynon-negativeinteger.lnannthordermatrix,exclusiveofthefirstrow,theelementsofeveryotherrowarethee1ementsoftheprecedingrowthatcirculaterightwardr-co1umns.Thisnthordermatrixisannthorderr-circulantFuzzymatrix(alsocalledgenearLizedcirculantFuzzymatrix)-Wecallrthecircu1antindexofr-circulantFuzzymatrix.Inthebooklistedin[1j,thisisgiven:… 相似文献
980.
We establish a duality formula for the problem Minimize f(x)+g(x) for h(x)+k(x)<0 where g, k are extended-real-valued convex functions and f, h belong to the class of functions that can be written as the lower envelope of an arbitrary family of convex functions. Applications in d.c. and Lipschitzian optimization are given. 相似文献