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991.
Error bounds for analytic systems and their applications   总被引:1,自引:0,他引:1  
Using a 1958 result of Lojasiewicz, we establish an error bound for analytic systems consisting of equalities and inequalities defined by real analytic functions. In particular, we show that over any bounded region, the distance from any vectorx in the region to the solution set of an analytic system is bounded by a residual function, raised to a certain power, evaluated atx. For quadratic systems satisfying certain nonnegativity assumptions, we show that this exponent is equal to 1/2. We apply the error bounds to the Karush—Kuhn—Tucker system of a variational inequality, the affine variational inequality, the linear and nonlinear complementarity problem, and the 0–1 integer feasibility problem, and obtain new error bound results for these problems. The latter results extend previous work for polynomial systems and explain why a certain square-root term is needed in an error bound for the (monotone) linear complementarity problem.The research of this author is based on work supported by the Natural Sciences and Engineering Research Council of Canada under grant OPG0090391.The research of this author is based on work supported by the National Science Foundation under grants DDM-9104078 and CCR-9213739 and by the Office of Naval Research under grant 4116687-01.  相似文献   
992.
张璞扬  蒋作宏 《大学物理》1997,16(10):26-27
根据费马原理,设想出一个由旋转椭球面与半径等于椭球短半轴的球面组成的透镜,使具有一定宽度的平行光束通过透镜后聚焦。  相似文献   
993.
994.
IntroductionConservationlawofmechanicalsystemnotonlyhasimportanceinmathematicsbutalsorevealsprofoundphysicallaw .In 1 91 8,basedoninvarianceofHamilton’sprincipleunderinfinitesimaltransformation ,theconservationlawofmechanicssystemwasstudiedbyGermanscientis…  相似文献   
995.
In this paper, with the help of symbolic computation, a new Backlund transformation (BT) for a newgeneralized Zakharov-Kuznetsov equation with nonlinear term of any order, ut+aupux +bu2pux +γuxy +δuxxx +ρuxyy=0, is obtained by using the homogeneous balance method. Based on the BT, some exact solutions are presented.  相似文献   
996.
We prove an extension of Ekeland's variational principle to locally complete spaces which uses subadditive, strictly increasing continuous functions as perturbations.  相似文献   
997.
New Type of Generalized Vector Quasiequilibrium Problem   总被引:1,自引:0,他引:1  
In this paper, we introduce a new type of vector quasiequilibrium problem with set-valued mappings and moving cones. By using the scalarization method and fixed-point theorem, we obtain its existence theorem. As applications, we derive some existence theorems for vector variational inequalities and vector complementarity problems. This work was supported by the National Natural Science Foundation of China. The authors are grateful to Professor X.Q. Yang and the referees for valuable comments and suggestions improving the original draft.  相似文献   
998.
In this paper, a kind of partial upwind finite element scheme is studied for twodimensional nonlinear convection-diffusion problem. Nonlinear convection term approximated by partial upwind finite element method considered over a mesh dual to the triangular grid, whereas the nonlinear diffusion term approximated by Galerkin method. A linearized partial upwind finite element scheme and a higher order accuracy scheme are constructed respectively. It is shown that the numerical solutions of these schemes preserve discrete maximum principle. The convergence and error estimate are also given for both schemes under some assumptions. The numerical results show that these partial upwind finite element scheme are feasible and accurate.  相似文献   
999.
环上矩阵的广义Moore-Penrose逆   总被引:7,自引:0,他引:7  
王志坚  刘晓冀 《数学杂志》2004,24(6):638-640
本文研究环上矩阵的广义Moore-Penros逆,利用矩阵行空间与列空间的包含关系,给出其存在的充要条件及表达式.推广了以往文献的相应结果。  相似文献   
1000.
In this paper, for a prime power q, new cyclic difference sets with Singer para- meters ((q n –1/q–1), (q n–1–1/q–1), (q n–2–1/q–1)) are constructed by using q-ary sequences (d-homogeneous functions) of period q n –1 and the generalization of GMW difference sets is proposed by combining the generation methods of d-form sequences and extended sequences. When q is a power of 3, new cyclic difference sets with Singer parameters ((q n –1/q–1), (q n–1–1/q–1), (q n–2–1/q–1)) are constructed from the ternary sequences of period q n –1 with ideal autocorrelation introduced by Helleseth, Kumar, and Martinsen.  相似文献   
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