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931.
Summary In the definition of semi-open sets and other kinds of generalized open sets, the role of the starting topology is given to a generalized topology. Some properties of the classes of sets so obtained is examined.  相似文献   
932.
在没有∑∞n=0αnβn<∞的更弱条件下,使用与完全不同的方法,证明了Ishikawa迭代序列强收敛Lipschitz连续的增生算子T的方程x+Tx=f的唯一解,并提供了更为全面和一般的收敛率的估计.本文结果是引文[3-4]中相应结果的统一和发展.  相似文献   
933.
We provide sufficient conditions for the convergence of the Newton-like methods in the assumption that the derivative satisfies some kind of weak Lipschitz conditions. Consequently, some important convergence theorems follow from our main result in this paper.  相似文献   
934.
Cauchy problem on non-globally hyperbolic space-times   总被引:1,自引:0,他引:1  
We consider solutions of the Cauchy problem for hyperbolic equations on non-globally hyperbolic space-times containing closed timelike curves (time machines). We prove that for the wave equation on such space-times, there exists a solution of the Cauchy problem that is discontinuous and in some sense unique for arbitrary initial conditions given on a hypersurface at a time preceding the formation of closed timelike curves. If the hypersurface of initial conditions intersects the region containing closed timelike curves, then the solution of the Cauchy problem exists only for initial conditions satisfying a certain self-consistency requirement. To Vasilii Sergeevich Vladimirov with best wishes on his 85th birthday __________ Translated from Teoreticheskaya i Matematicheskaya Fizika, Vol. 157, No. 3, pp. 334–344, December, 2008.  相似文献   
935.
1Introduction and PreliminariesThroughout this paper,we consider linear spaces over the complex numbers C.Given alinear space X and integers m and n,let Mm,n(X)=X?Mm,n denote the linear space ofm×n matricesx=?????x.x..m1,1,1.x..xm1,n,n?????with entries x…  相似文献   
936.
Summary Selenia Spazio was involved since its beginning, more than twenty years ago, in scientific space missions, like almost all space industries in the world. In fact the European space organizations were mainly devoted to the development of autonomous launchers and to scientific research in the nearby and in the far away space. First programs in which Selenia Spazio had a role, designing and manufacturing space electronic equipment, were scientific satellites and ELDO launchers, followed by COSB and other cosmic research missions. In all these years cosmic physics and related research programs continued to receive technological support and see full involvement by space industry. To speed up publication, the proofs were not sent to the authors and were supervised by the Scientific Committee.  相似文献   
937.
938.
This article presents solutions for the transient heat and moisture transport due to both disk heat source and cylindrical heat source buried in an unsaturated half space. The solutions are presented in Hankel–Laplace transform domain and in dimensionless style. Coupled effect of thermally driven moisture transport is especially investigated because of its importance to alter the flow field in low-permeability medium. Parametric study has been performed to assess the effects of five independent dimensionless parameters on flow field. The stability and accuracy of the present solutions are demonstrated from the comparison between the results obtained from these solutions and those by using a well-established finite element code CODE_BRIGHT. Despite the simplified assumptions required in order to obtain analytical solutions in Hankel–Laplace transform domain, the results incorporate the main mechanisms involved in the coupled thermo-hydraulic (T-H) problem, and they may be eventually used for validation purposes.  相似文献   
939.
We provide two new positive mass theorems under respective modified energy conditions allowing T00 negative on some compact set for certain modified asymptotically hyperbolic manifolds. This work is analogous to Zhang’s previous result for modified asymptotically ?at initial data sets.  相似文献   
940.
在非紧超凸度量空间中建立了一个新的极大元定理.作为应用,获得了连续选择及其不动点定理和一个Browder-Fan不动点定理.最后,新建了非紧超凸度量空间中的定性对策和抽象经济的平衡点存在定理.  相似文献   
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