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891.
892.
We obtain an upper bound for the upper subderivative of the marginal function of an abstract parametric optimization problem when the objective function is lower semicontinuous. Moreover, we apply the result to a nonlinear program with right-hand side perturbations. As a result, we obtain an upper bound for the upper subderivative of the marginal function of a nonlinear program with right-hand side perturbations, which is expressed in dual form in terms of appropriate Lagrange multipliers. Finally, we present conditions which imply that the marginal function is locally Lipschitzian.  相似文献   
893.
系数变号时经典Emden方程的两点边值问题的正解   总被引:3,自引:0,他引:3  
建立了边值问题w″ k(t)w^α=0,w(0)=w(1)=0的一个正解存在定理,其中允许k(t)的[0,1]上改变符号。  相似文献   
894.
二阶系统边值问题的正解   总被引:1,自引:0,他引:1  
以关于非线性全连续算子的锥不动点定为工具,研究二阶系统边值问题,在不假定f,g单调的情况下,得出了上述问题存在正解的若干充分条件。  相似文献   
895.
Let be the Lorentz/second-order cone in . For any function f from to , one can define a corresponding function fsoc(x) on by applying f to the spectral values of the spectral decomposition of x with respect to . We show that this vector-valued function inherits from f the properties of continuity, (local) Lipschitz continuity, directional differentiability, Fréchet differentiability, continuous differentiability, as well as (-order) semismoothness. These results are useful for designing and analyzing smoothing methods and nonsmooth methods for solving second-order cone programs and complementarity problems.Mathematics Subject Classification (1991): 26A27, 26B05, 26B35, 49J52, 90C33, 65K05  相似文献   
896.
By using the concept of almost periodic "sequence", that is, a real valued function on Z satisfying the Bohr almost periodic condition, sufficient conditions are obtained for the existence of almost periodic solutions of Lasota-Wazewska-type differential equations with almost periodic time dependence.  相似文献   
897.
A simple device capable to produce Bessel beams with variable cone angle is proposed. It is shown that the cone angle of the Bessel beam produced by the axicone placed inside the telescope depends on the position of the axicone and can be continuously varied. As a result of theoretical investigations a simple formula giving the cone half-angle on the parameters and position of axicone inside the telescope was derived. The possibility of the Bessel beam generation with the help of a proposed device was confirmed experimentally. Good qualitative and quantitative agreement with the theoretical predictions is obtained.  相似文献   
898.
Kalauch  A.  Weber  M.R. 《Positivity》2000,4(2):179-195
The equation for a positive linear continuous operator is considered in an ordered normed space , where the cone is assumed to be closed and having a nonempty interior. Then the dual cone of K possesses a base . Generalizing the well known maximum principle for positive matrices an operator A is said to satisfy the maximum principle, if for any there exists a positive linear continuous functional which is both, maximal on the element Ax, i.e. , and positive on the element x, i.e. 0$$ " align="middle" border="0"> . This property is studied and characterized both analytically by some extreme point condition and geometrically by means of the behaviour under A of the faces of the cone K. It is shown that the conditions which have been obtained for finite dimensional spaces in earlier relevant papers are special cases of conditions presented in this paper. The maximum pinciple is proved for simple operators in the spaces and c.  相似文献   
899.
Piotr M. Hajac 《K-Theory》2000,21(2):141-150
The Noncommutative Index Theorem is used to prove that the Chern numbers of quantum Hopf line bundles over the standard Podle quantum sphere equal the winding numbers of the representations defining these bundles. This result gives an estimate of the positive cone of the algebraic K0 of the standard quantum sphere.  相似文献   
900.
侯璐景  姜克  王友年 《物理》2007,36(3):203-206
当船在水中自由滑行时,一方面会在水面产生一个“V”型的尾波,另一方面它会由于水的摩擦而不断减速.有意思的是,当带电粒子在二维强耦合尘埃等离子体表面飞行时,也会发生类似的现象.  相似文献   
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