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1.
《Physics letters. A》2020,384(35):126904
Exploring the evolution of cooperation has been one of the most challenging topics and attracted increasing attention in various realms. Hereby, we institute an analytic model where the relationship between the common benefits and contributions is the typical saturation nonlinearity. We investigate the evolutionary dynamics of cooperation with and without consensual incentives respectively. The population always evolves to full defection when the incentives are absent. Cooperation, however, can be promoted by consensual incentives when the degree of cooperators' preferences for incentives is great. There exists an intermediate amount of resources at which the positive effect of consensual incentives on cooperation is minimized. Furthermore, there is a U-shape relationship between the degree of cooperators' preference for an incentive and the evolution of cooperation. A greater basin of full cooperation can be induced when the cooperators' preference for reward is more pronounced than that for punishment.  相似文献   
2.
This paper through discussing subdifferentiability and convexity of convex functions shows that a Banach space admits an equivalent uniformly [locally uniformly, strictly] convex norm if and only if there exists a continuous uniformly [locally uniformly, strictly] convex function on some nonempty open convex subset of the space and presents some characterizations of super-reflexive Banach spaces. Supported by NSFC  相似文献   
3.
Murty's algorithm for the linear complementarity problem is generalized to solve the optimality conditions for linear and convex quadratic programming problems with both equality and inequality constraints. An implementation is suggested which provides both efficiency and tight error control. Numerical experiments as well as field tests in various applications show favorable results.The author thanks K. G. Murty for his encouragement and helpful comments.  相似文献   
4.
Well-Posedness by Perturbations of Variational Problems   总被引:3,自引:0,他引:3  
In this paper, we consider the extension of the notion of well-posedness by perturbations, introduced by Zolezzi for optimization problems, to other related variational problems like inclusion problems and fixed-point problems. Then, we study the conditions under which there is equivalence of the well-posedness in the above sense between different problems. Relations with the so-called diagonal well-posedness are also given. Finally, an application to staircase iteration methods is presented.  相似文献   
5.
The method of equivalent variational methods, originally due to Carathéodory for free problems in the calculus of variations is extended to investigate feedback Nash equilibria for a class of n-person differential games. Both the finite-horizon and infinite-horizon cases are considered. Examples are given to illustrate the presented results.  相似文献   
6.
The Hahn–Banach Theorem for partially ordered totally convex modules [3] and a necessary and sufficient condition for the existence of an extension of a morphism from a submodule C 0 of a partially ordered totally convex module C (with the ordered unit ball of the reals as codomain) to C, are proved. Moreover, the categories of partially ordered positively convex and superconvex modules are introduced and for both categories the Hahn–Banach Theorem is proved.  相似文献   
7.
线性分式规划最优解集的求法   总被引:5,自引:0,他引:5  
本文使用多面集的表示定理,导出了线性分式规划最优解集的结构,并给出确定全部最优解的计算步骤。  相似文献   
8.

This paper gives some global and uniform convergence estimates for a class of subspace correction (based on space decomposition) iterative methods applied to some unconstrained convex optimization problems. Some multigrid and domain decomposition methods are also discussed as special examples for solving some nonlinear elliptic boundary value problems.

  相似文献   

9.
提出了一种能用凸四边形表示并可作平面展开的三维实体造型的设计方法。该方法用旋转描述表把二维平面展开图和三维实体联系起来,模拟人工折叠过程,由二维平面展开图逐次旋转变换完成三维造型重建。造型重建后,再通过纹理映射将平面设计图案映射到实体的各个面上,完成对实体着色渲染,生成具有真实感的三维实体。  相似文献   
10.
一致Banach空间中非扩张映象的弱收敛定理   总被引:6,自引:0,他引:6       下载免费PDF全文
设犈是一致凸Banach空间,满足Opial条件或具有Frechet可微范数,犆是犈的非空闭凸子集,且犜:犆→犆是非扩张映象.又设对任何初始数据狓1 ∈犆,序列{狓狀}由下列修改了的Ishikawa迭代程序生成:狓狀+1 =狋狀犜狀(狊狀犜狀狓狀+ (1-狊狀)狓狀)+ (1-狋狀)狓狀, 狀≥1, (I)其中,数列{狋狀}与{狊狀}满足下列条件(i)和(ii)之一:(i)狋狀∈ [犪,犫]且狊狀∈ [0,犫];(ii)狋狀∈ [犪,1]且狊狀∈ [犪,犫],这里,常数犪,犫满足0<犪≤犫<1.作者证明了,犜有不动点的充要条件是,{狓狀} 弱收敛且{‖狓狀-犜狓狀‖}收敛到0.而且,由此即知,若犜有不动点,则{狓狀}弱收敛到犜的一个不动点.  相似文献   
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