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41.
在Banach空间中, 利用半序方法讨论了一类抽象算子方程组解的存在唯一性, 推广和统一了以前的一些结果. 然后应用到 Banach 空间非线性积分方程组, 得到了方程组的唯一解, 构造了收敛于方程组唯一解的迭代序列并给出了相应的误差估计.  相似文献   
42.
一类多偏差变元的二阶微分方程周期解   总被引:1,自引:0,他引:1  
朱敏  鲁世平 《数学研究》2007,40(1):37-45
本文利用重合度理论研究了一类二阶多偏差变元的微分方程 x"(t)+f(t,x(t),x(t-τ0(t)),x'(t))+∑nj=1g(x(t-τj(t)))=p(t) 的周期解问题,得到了存在周期解的新的结果.  相似文献   
43.
The analytic continuation of the exponential transform of a domain in Rn is proved under some global geometric assumptions on the boundary. Two approximation schemes of the continued transform (one based on a Taylor series truncation, the other on a global eigenfunction expansion) are also discussed.  相似文献   
44.
This paper is concerned with a generalized Arzela–Ascoli's lemma, which has been extensively applied in almost periodic problems by the continuation theorem of degree theory. We give a counter example to show that this lemma is incorrect, and there is a gap in the proof of some existing literature, where the addressed generalized Arzela–Ascoli's lemma was used. Moreover, we make some final comments and introduce an open problem. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
45.
The problem of orbit determination using one or two GPS satellites is discussed. Methods of getting initial values based on linear translation is presented; the Secant method and the descend Newton iterative procedure and the continuation algorithm are used synthetically to solve the nonlinear equations. Computer simulation shows that this algorithm can give preliminary state of satellite orbit with a certain precision in short time.  相似文献   
46.
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   
47.
UNIQUE CONTINUATION ON A HYPERPLANE FOR WAVE EQUATION   总被引:1,自引:0,他引:1  
51.IntroductionTheuniquecontinuationisthat,ifasolutionofapartialdifferentialequationvanishesinanopenset,thenitmustvanishontheconnectedcomponentwhichcontainsthisopenset.Itiswellunderstoodforellipticoperatorsofthesecondorder.In1939,Carleman[2]showedauniquecontinuationtheoremforsystemsofpartialdifferentia1equationsinthetwodimensionalcasewhosecoefficientsarenotanalytic.Thepowerfu1techniquewhichheproposediscal1edaCaJrlemanestimateandhasplayedacentralroleinthedevelopmentofuIilquecontinuationaJrgum…  相似文献   
48.
We consider the space of countable structures with fixed underlying set in a given countable language. We show that the number of ergodic probability measures on this space that are S-invariant and concentrated on a single isomorphism class must be zero, or one, or continuum. Further, such an isomorphism class admits a unique S-invariant probability measure precisely when the structure is highly homogeneous; by a result of Peter J. Cameron, these are the structures that are interdefinable with one of the five reducts of the rational linear order (Q,<).  相似文献   
49.
In this article, we consider dynamic behaviours of a class of non-linear delay stochastic evolution equations. Local existence and uniqueness of the solutions are obtained with the aid of proper iterative scheme and moment estimations. We also propose a continuation result and our results generalize the known results.  相似文献   
50.

In this paper, we prove the rank one case of Dwork's conjecture on the -adic meromorphic continuation of the pure slope L-functions arising from the slope decomposition of an overconvergent F-crystal. Further explicit information about zeros and poles of the pure slope L-functions are also obtained, including an application to the Gouvêa-Mazur type conjecture in this setting.

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