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901.
Andrew Bakan 《Journal of Mathematical Analysis and Applications》2007,333(1):347-364
In this paper we shall study Hardy spaces of analytic functions in a strip S. Our main result is on one hand an intrinsic characterization of the spaces and on the second that polynomials are dense. We also present an orthogonal (in H2(S)) basis of polynomials. 相似文献
902.
Jackson’s theorem is established in a new kind of holomorphic function space Qμ related to measures in any starlike circular domain in . Particularly, the result covers many spaces including BMOA, Qp, QK, and F(p,q,s) spaces in the unit ball of . Moreover, we construct integral operators which give pointwise estimates for the gradient of the difference in terms of the gradient on the boundary. The gradient estimates are independent of the measures in question and give rise to Jackson’s theorem. 相似文献
903.
A quantitative version of Trotter's approximation theorem 总被引:1,自引:1,他引:1
A quantitative version, based on modified K-functionals, of the classical Trotter's theorem concerning the approximation of C0-semigroups is presented. The result is applied to the study of the degree of convergence of the iterated Bernstein operators on the N-dimensional simplex to their limiting semigroup. 相似文献
904.
The total energies and structural parameters of SrTcO3 are calculated by means of the generalized gradient approximation (GGA) plus on-site Coulomb interaction corrections (GGA+U) method. G-type antiferromagnetic (G-AFM) is found to be ground state, in consistence with the previous experimental result. The distortions around Sr and Tc upon magnetic transition are compared and the change of distortion for SrO bond upon magnetic transition is found to be 25.83 times of the change for TcO bond. Our results point to an active role played by Sr in magnetostructural coupling in SrTcO3. 相似文献
905.
We prove that an analytic function f on the unit ball B with Hadamard gaps, that is, (the homogeneous polynomial expansion of f) satisfying nk+1/nk?λ>1 for all k∈N, belongs to the space if and only if . Moreover, we show that the following asymptotic relation holds . Also we prove that limr→1(1-r2)α‖Rfr‖p=0 if and only if . These results confirm two conjectures from the following recent paper [S. Stevi?, On Bloch-type functions with Hadamard gaps, Abstr. Appl. Anal. 2007 (2007) 8 pages (Article ID 39176)]. 相似文献
906.
科学研究是高校的四大重要职能之一,也是一个大学综合实力的重要体现,高校对教师科研创新的激励政策和管理对全校科研氛围至关重要。以参与人有限理性为前提,本文首先分析了高校当前体制环境下影响科研工作者和管理部门决策的因素,基于演化博弈视角建立高校科研工作者与管理部门之间行为的博弈支付矩阵,构建了相关行为的复制动态方程,然后,基于演化博弈理论研究了科研人员和管理部门行为的演化路径以及影响演化的因素,研究得出了科研人员个体不同策略选择对群体行为产生的影响。为系统化、定量化的研究科研创新行为,本文基于Matlab GUI平台对科研创新与管理进行了演化仿真。系统分析了不同的初始条件和决策参数对演化结果的影响。本文的分析方法可为高校及科研管理部门提供决策支持,以适时采取适度的奖励政策,引导科研向高水平方向演化,提高高校的科研创新水平。 相似文献
907.
针对信息泄露导致零售商信息共享意愿降低的问题,基于竞争型制造商创新的视角,构建了考虑信息泄露的零售商需求预测信息共享模型,求解了供应链各主体的均衡决策,分析了信息泄露对零售商信息共享的影响。研究发现:虽然需求预测信息泄露能够增加两个竞争型制造商的创新投入,但会削弱博弈主导制造商的领导者优势。上游竞争型供应链中的信息泄露会削弱下游零售商的事前利润,零售商的信息共享价值降低。本文克服了Shamir关于供应链需求信息泄露局限于零售商的不足,并进一步考虑了制造商之间的竞争和创新。 相似文献
908.
针对产业集群协同创新中核心企业和配套企业的知识共享问题, 通过构建微分博弈模型, 运用HJB方程分别考察三种知识共享博弈情形下核心企业和配套企业的最优知识共享策略。通过三种博弈结果的比较分析发现:Stackelberg主从博弈情形下, 知识共享投入补贴作为一种激励策略可促进配套企业知识共享意愿、双方各自知识共享收益以及双方知识共享总收益均优于Nash非合作情形;协同合作博弈情形下双方各自知识共享意愿、各自知识共享收益和双方知识共享总收益均优于非合作情形, 且收益分配系数α存在一个阈值, 可实现双方个体收益的帕累托最优。最后, 通过数值算例分析验证了理论推导的结果。 相似文献
909.
《Operations Research Letters》2020,48(3):286-290
We consider a real option model in which a principal funds an agent to implement a project. Success depends on the quality of the project as well as the unknown ability of the agent. The possibility of the agent diverting project implementation funds to his private uses creates an agency problem which leads to delayed investment and over-experimentation. The principal prefers to fund an agent who is overconfident about his ability and such overconfidence reduces inefficiency due to agency problem. 相似文献
910.
Pavol Hell 《Discrete Mathematics》2009,309(18):5703-5373
A sequence 〈d1,d2,…,dn〉 of non-negative integers is graphical if it is the degree sequence of some graph, that is, there exists a graph G on n vertices whose ith vertex has degree di, for 1≤i≤n. The notion of a graphical sequence has a natural reformulation and generalization in terms of factors of complete graphs.If H=(V,E) is a graph and g and f are integer-valued functions on the vertex set V, then a (g,f)-factor of H is a subgraph G=(V,F) of H whose degree at each vertex v∈V lies in the interval [g(v),f(v)]. Thus, a (0,1)-factor is just a matching of H and a (1, 1)-factor is a perfect matching of H. If H is complete then a (g,f)-factor realizes a degree sequence that is consistent with the sequence of intervals 〈[g(v1),f(v1)],[g(v2),f(v2)],…,[g(vn),f(vn)]〉.Graphical sequences have been extensively studied and admit several elegant characterizations. We are interested in extending these characterizations to non-graphical sequences by introducing a natural measure of “near-graphical”. We do this in the context of minimally deficient (g,f)-factors of complete graphs. Our main result is a simple linear-time greedy algorithm for constructing minimally deficient (g,f)-factors in complete graphs that generalizes the method of Hakimi and Havel (for constructing (f,f)-factors in complete graphs, when possible). It has the added advantage of producing a certificate of minimum deficiency (through a generalization of the Erdös-Gallai characterization of (f,f)-factors in complete graphs) at no additional cost. 相似文献