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排序方式: 共有1541条查询结果,搜索用时 109 毫秒
141.
By cone theory and the fixed point index,we study the existence of positive solutions to a three-order boundary value problem with dependence on the first order derivative. 相似文献
142.
In this article, we study the second-order optimality conditions for a class of circular conic optimization problem. First, the explicit expressions of the tangent cone and the second-order tangent set for a given circular cone are derived. Then, we establish the closed-form formulation of critical cone and calculate the “sigma” term of the aforementioned optimization problem. At last, in light of tools of variational analysis, we present the associated no gap second-order optimality conditions. Compared to analogous results in the literature, our approach is intuitive and straightforward, which can be manipulated and verified. An example is illustrated to this end. 相似文献
143.
Qing MENG 《数学年刊B辑(英文版)》2019,40(3):429-438
In this paper, the author first introduces the concept of
generalized algebraic cone metric spaces and some elementary results
concerning generalized algebraic cone metric spaces. Next, by using
these results, some new fixed point theorems on generalized
(complete) algebraic cone metric spaces are proved and an example is
given. As a consequence, the main results generalize the
corresponding results in complete algebraic cone metric spaces and
generalized complete metric spaces. 相似文献
144.
利用基于集合Ph,e上的一类混合单调算子不动点定理,研究了一类Riemann Liouville分数阶微分方程两点边值问题,获得了这类方程在集合Ph,e中解的存在性与唯一性,并用一组单调迭代序列逼近了该方程的唯一非平凡解.最后,利用一个实例验证了主要结论. 相似文献
145.
E. De Pascale L. De Pascale 《Proceedings of the American Mathematical Society》2002,130(11):3249-3254
The use of K-normed spaces gives us the possibility to prove that a fixed point theorem due to B. Luo is equivalent to the Banach Contraction Principle. This confirms the conspiracy among fixed point theorems. Moreover the theorem of Lou is improved and extended to different contexts. A counterexample about the fixed points of the sum of a contraction and an integral operator is given. The usefulness of K-norm is tested on a Volterra integral equation as well.
146.
本文讨论了 Banach空间中 Sturm-Liouville问题正解的存在性与多解性,通过线性算子的谱半径,给出其正解存在与多解的条件. 相似文献
147.
We illustrate the usefulness of Jordan-algebraic techniques for nonconvex optimization by considering a potential-reduction
algorithm for a nonconvex quadratic function over the domain obtained as the intersection of a symmetric cone with an affine
subspace. 相似文献
148.
Steady free convection boundary layer about a truncated cone embedded in a porous medium saturated with pure or saline water at low temperatures has been studied in this paper. The governing coupled partial differential equations are solved numerically using a very efficient finite-difference method. Several new parameters arise and the results are given for some specific values of these parameters. The obtained results for a Boussinesq fluid are compared with known results from the open literature and it is shown that the agreement between these results is very good. 相似文献
149.
区间判断的凸锥模型与排序方法 总被引:5,自引:2,他引:3
本文用凸锥模型对层次分析法中区间判断条件下的排序问题进行研究,给出了权重向量的合理算法.并对区间判断下权重向量的合理位置,产生逆序的可能性等重要问题进行了探讨和研究,给出了计算实例. 相似文献
150.
We provide analogues of Carathéodory's theorem for integer cones and apply our bounds to integer programming and to the cutting stock problem. In particular, we provide an NP certificate for the latter, whose existence has not been known so far. 相似文献