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11.
12.
多偏差变元中立型Rayleigh方程周期解问题 总被引:5,自引:0,他引:5
作者研究了一类多偏差变元中立型Rayleigh方程周期解问题,利用Mawhin重合度拓展定理得到了周期解存在性的新结果. 相似文献
13.
Jin Cheng Ching-Lung Lin Gen Nakamura 《Proceedings of the American Mathematical Society》2005,133(8):2359-2367
In this paper we prove the following kind of unique continuation property. That is, the zero on each geodesic of the solution in a real analytic hypersurface for second order anisotropic hyperbolic systems with real analytic coefficients can be continued along this curve.
14.
A. I. Pavlov 《Mathematical Notes》1999,66(4):442-450
The main result of the paper is as follows.Theorem. Suppose that G(z) is an entire function satisfying the following conditions: 1) the Taylor coefficients of the function
G(z) are nonnegative: 2) for some fixed C>0 and A>0 and for |z|>R0, the following inequality holds:
Further, suppose that for some fixed α>0 the deviation DN of the sequence xn={αn}, n=1, 2, ..., as N→∞ has the estimate DN=0(lnB N/N). Then if the function G(z) is not an identical constant and the inequality B+1<A holds, then the power series
converging in the disk |z|<1 cannot be analytically continued to the region |z|>1 across any arc of the circle |z|=1.
Translated fromMatematicheskie Zametki, Vol. 66, No. 4, pp. 540–550, October, 1999. 相似文献
15.
该文考虑一类特殊的抛物型方程侧边值问题,即一类含有对流项的非标准逆热传导问题. 给定在x=1处的温度测量值来确定区间(0,1)上的未知解u(x, t). 这是一类不适定问题,即问题的解(如果解存在)不连续依赖于数据.为了求解这一问题,
必须采用某些正则化技巧. 该文给出了一种最优滤波方法, 使得问题的真实解和近似解之间的误差估计达到了Hölder型最优. 同时还证明了问题的解在x=0处的收敛性. 相似文献
16.
A. J. Mkrtchyan 《Mathematische Nachrichten》2019,292(11):2441-2451
For multiple power series centered at the origin we consider the problem of its analytic continuability into a sectorial domain. The condition for continuability is formulated in terms of a holomorphic function that interpolates the series coefficients. For series in one variable this problem has been studied in the works of E. Lindelöf, N. Arakelian, and others. 相似文献
17.
Aubrey B. Poore 《Annals of Operations Research》1990,27(1):343-369
Bifurcation and continuation techniques are introduced as a class of methods for investigating the parametric nonlinear programming problem. Motivated by the Fritz John first-order necessary conditions, the parametric programming problem is first reformulated as a closed system of nonlinear equations which contains all Karush-Kuhn-Tucker and Fritz John points, both feasible and infeasible solutions, and relative minima, maxima, and saddle points. Since changes in the structure of the solution set and critical point type can occur only at singularities, necessary and sufficient conditions for the existence of a singularity are developed in terms of the loss of a complementarity condition, the linear dependence constraint qualification, and the singularity of the Hessian of the Lagrangian on a tangent space. After a brief introduction to elementary bifurcation theory, some simple singularities in this parametric problem are analyzed for both branching and persistence of local minima. Finally, a brief introduction to numerical continuation and bifurcation procedures is given to indicate how these facts can be used in a numerical investigation of the problem.This research was supported by the Air force Office of Scientific Research through grant number AFOSR-88-0059. 相似文献
18.
迭代微分方程解的存在性及分支 总被引:5,自引:0,他引:5
本文讨论迭代微分方程x(t)=f(x(t),x(x(t)))的解的性态,并在f(x(t),x(x(t)))=(x^2(t)-μ)x(x(t))时研究解的分支问题,更正了现有文献中的错误,结出了正确,完整的结果。 相似文献
19.
Michele Di Cristo Luca Rondi Sergio Vessella 《Annali di Matematica Pura ed Applicata》2006,185(2):223-255
We treat the stability issue for an inverse problem arising from non-destructive evaluation by thermal imaging. We consider
the determination of an unknown portion of the boundary of a thermic conducting body by overdetermined boundary data for a
parabolic initial-boundary value problem. We obtain that when the unknown part of the boundary is a priori known to be smooth,
the data are as regular as possible and all possible measurements are taken into account, the problem is exponentially ill-posed.
Then, we prove that a single measurement with some a priori information on the unknown part of the boundary and minimal assumptions
on the data, in particular on the thermal conductivity, is enough to have stable determination of the unknown boundary. Given
the exponential ill-posedness, the stability estimate obtained is optimal.
AMS 2000 Mathematics Subject Classification. Primary 35R30, Secondary 35B60, 33C90 相似文献
20.
M. Van Barel Kh. D. Ikramov A. A. Chesnokov 《Computational Mathematics and Mathematical Physics》2008,48(12):2126-2139
A fast algorithm is proposed for solving symmetric Toeplitz systems. This algorithm continuously transforms the identity matrix into the inverse of a given Toeplitz matrix T. The memory requirements for the algorithm are O(n), and its complexity is O(log κ(T)nlogn), where (T) is the condition number of T. Numerical results are presented that confirm the efficiency of the proposed algorithm. 相似文献