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991.
Behzad Djafari Rouhani Hadi Khatibzadeh 《Journal of Mathematical Analysis and Applications》2010,363(2):648-654
In this paper, we establish the strong convergence of possible solutions to the following nonhomogeneous second order evolution system
992.
In this paper, we give two explicit examples of unbounded linear maximal monotone operators. The first unbounded linear maximal monotone operator S on ?2 is skew. We show its domain is a proper subset of the domain of its adjoint S∗, and −S∗ is not maximal monotone. This gives a negative answer to a recent question posed by Svaiter. The second unbounded linear maximal monotone operator is the inverse Volterra operator T on L2[0,1]. We compare the domain of T with the domain of its adjoint T∗ and show that the skew part of T admits two distinct linear maximal monotone skew extensions. These unbounded linear maximal monotone operators show that the constraint qualification for the maximality of the sum of maximal monotone operators cannot be significantly weakened, and they are simpler than the example given by Phelps-Simons. Interesting consequences on Fitzpatrick functions for sums of two maximal monotone operators are also given. 相似文献
993.
In this paper we examine existence of monotone approximations of solutions of singular boundary value problem -(p(x)y′(x))′=q(x)f(x,y,py′) for 0<x?b and limx→0+p(x)y′(x)=0,α1y(b)+β1p(b)y′(b)=γ1. Under quite general conditions on f(x,y,py′) we show that solution of the singular two point boundary value problem is unique. Here is allowed to have integrable singularity at x=0 and we do not assume . 相似文献
994.
Tadeusz Jankowski 《Applied mathematics and computation》2010,216(4):1242-1249
We investigate the existence of solutions to nonlinear first-order difference problems with advanced arguments. Sufficient conditions when such problems have solutions (extremal or unique) are given. Linear advanced difference inequalities are also discussed. According to my knowledge, it is a first paper when a monotone iterative method is applied to nonlinear boundary value problems for first-order difference equations with advanced arguments. An example illustrates the theoretical results. 相似文献
995.
Ilse Fischer 《Journal of Combinatorial Theory, Series A》2010,117(8):1143-1157
We provide a simplified proof of our operator formula for the number of monotone triangles with prescribed bottom row, which enables us to deduce three generalizations of the formula. One of the generalizations concerns a certain weighted enumeration of monotone triangles which specializes to the weighted enumeration of alternating sign matrices with respect to the number of −1s in the matrix when prescribing (1,2,…,n) as the bottom row of the monotone triangle. 相似文献
996.
Let be the standard closed positive cone in and let be the set of integers for which there exists a continuous, order preserving, subhomogeneous map , which has a periodic point with period . It has been shown by Akian, Gaubert, Lemmens, and Nussbaum that is contained in the set consisting of those for which there exist integers and such that , , and for some . This note shows that for all .
997.
K. Kopotun D. Leviatan A. V. Prymak 《Proceedings of the American Mathematical Society》2006,134(7):2037-2047
It is shown that the rate of -approximation of a non-decreasing function in , , by ``nearly non-decreasing" splines can be estimated in terms of the third classical modulus of smoothness (for uniformly spaced knots) and third Ditzian-Totik modulus (for Chebyshev knots), and that estimates in terms of higher moduli are impossible. It is known that these estimates are no longer true for ``purely" monotone spline approximation, and properties of intervals where the monotonicity restriction can be relaxed in order to achieve better approximation rate are investigated.
998.
Youssef N. Raffoul 《Journal of Mathematical Analysis and Applications》2006,324(2):1356-1362
In this research we study the stability of the zero solution of delay difference equations and the existence of unique periodic solution by utilizing fixed point theory. Mainly, we are interested in the qualitative analysis of the complete delay difference equation
Δx(t)=−a(t)x(t−τ). 相似文献
999.
1000.
《复变函数与椭圆型方程》2012,57(5):447-451
For a small closed disk D in the complex plane the uniform closure A in C ( D ) of the polynomials in z 2 and a second function of the form f 2 , with f behaving as [zbar], is considered. It has been shown before, using theory of polynomial convexity, that A p C ( D ) for some choices of f , while for other choices of f the situation A = C ( D ) can occur. A new class of functions f is presented for which A = C ( D ). 相似文献