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91.
Dragoslav Herceg 《Numerische Mathematik》1989,56(7):675-693
Summary The numerical solution of a nonlinear singularly perturbed two-point boundary value problem is studied. The developed method is based on Hermitian approximation of the second derivative on special discretization mesh. Numerical examples which demonstrate the effectiveness of the method are presented.This research was partly supported by NSF and SIZ for Science of SAP Vojvodina through funds made available to the U.S.-Yugoslav Joint Board on Scientific and Technological Cooperation (grants JF 544, JF 799) 相似文献
92.
I. Palásti 《Periodica Mathematica Hungarica》1989,20(3):231-235
Here we establish a set of eight points in general position in the plane, i.e. no three on a line, no four on a circle, and they determine 7 distinct distances, so that, thei-th distance occursi times,i = 1, 2, LE" BORDER="0">, 7. The points are embedded in a triangular net, and the distances are not ordered by size or in any other way. We shall show that some known and unknown examples forn < 8 with the above properties may also be lattice points of a similar net.Research (partially) supported by the Hungarian National Foundation for Scientific Research (OTKA) grant, no. 1808. 相似文献
93.
Recently, Chawla et al. described a second order finite difference method for the class of singular two-point boundary value problems:
相似文献
94.
Josef Schneid 《BIT Numerical Mathematics》1988,28(1):184-187
Lower bounds for LINE" BORDER="0"> are given for which equidistant s-point collocation methods areA(LINE" BORDER="0">)-stable for arbitrarys. 相似文献
95.
Summary Integral operators are nonlocal operators. The operators defined in boundary integral equations to elliptic boundary value problems, however, are pseudo-differential operators on the boundary and, therefore, provide additional pseudolocal properties. These allow the successful application of adaptive procedures to some boundary element methods. In this paper we analyze these methods for general strongly elliptic integral equations and obtain a-posteriori error estimates for boundary element solutions. We also apply these methods to nodal collocation with odd degree splines. Some numerical examples show that these adaptive procedures are reliable and effective.This work was carried out while Dr. De-hao Yu was an LE" BORDER="0">Alexander-von-Humboldt-StiftungLE" BORDER="0"> research fellow at the University of Stuttgart in 1987, 1988 相似文献
96.
Summary Standard analysis of multistep methods for ODE's assumes the application of an initialization routine that generates the starting points. Here ak-step method is considered directly as a mappingR
kn
LINE" BORDER="0">R
n
. It is shown to approximate a mapping which is expressible directly in terms of the flow of the vector field. Some useful properties of that mapping are shown and for strictly stable methods these are applied to the question of invariant circles near a hyperbolic periodic solution. 相似文献
97.
C. Lubich 《Numerische Mathematik》1988,52(2):129-145
Numerical methods are derived for problems in integral equations (Volterra, Wiener-Hopf equations) and numerical integration (singular integrands, multiple time-scale convolution). The basic tool of this theory is the numerical approximation of convolution integrals
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