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991.
This paper investigates the existence of absolute optimal solutions for a partition P in continuous and quasiconcave games. We show that the P-consistency property introduced in the paper, together with the quasiconcavity and continuity of payoffs, permits the existence of P-absolute optimal solutions in games with compact and convex strategy spaces. The P-consistency property is a general condition that cannot be dispensed with for the existence of P-absolute optimal solutions. We also characterize the existence of P-absolute optimal solutions by providing necessary and sufficient conditions. Moreover, we suggest an algorithm for efficiently computing P-absolute optimal solutions. 相似文献
992.
Yugang Yu Zhaofu Hong Linda L. Zhang Liang Liang Chengbin Chu 《European Journal of Operational Research》2013
A Vendor Managed Inventory (VMI) system consists of a manufacturing vendor and a number of retailers. In such a system, it is essential for the vendor to optimally determine retailer selection and other related decisions, such as the product’s replenishment cycle time and the wholesale price, in order to maximize his profit. Meanwhile, each retailer’s decisions on her willingness to enter the system and retail price are simultaneously considered in the retailer selection process. However, the above interactive decision making is complex and the available studies on interactive retailer selection are scarce. In this study, we formulate the retailer selection problem as a Stackelberg game model to help the manufacturer, as a vendor, optimally select his retailers to form a VMI system. This model is non-linear, mixed-integer, game-theoretic, and analytically intractable. Therefore, we further develop a hybrid algorithm for effectively and efficiently solving the developed model. The hybrid algorithm combines dynamic programming (DP), genetic algorithm (GA) and analytical methods. As demonstrated by our numerical studies, the optimal retailer selection can increase the manufacturer’s profit by up to 90% and the selected retailers’ profits significantly compared to non-selection strategy. The proposed hybrid algorithm can solve the model within a minute for a problem with 100 candidate retailers, whereas a pure GA has to take more than 1 h to solve a small sized problem of 20 candidate retailers achieving an objective value no worse than that obtained by the hybrid algorithm. 相似文献
993.
We consider jointly replenishing n ex-ante identical firms that operate under an EOQ like setting using a non-cooperative game under asymmetric information. In this game, each firm, upon being privately informed about its demand rate (or inventory cost rate), submits a private contribution to an intermediary that specifies how much it is willing to pay for its replenishment per unit of time and the intermediary determines the maximum feasible frequency for the joint orders that would finance the fixed replenishment cost. We show that a Bayesian Nash equilibrium exists and characterize the equilibrium in this game. We also show that the contributions are monotone increasing in each firm’s type. We finally conduct a numerical study to compare the equilibrium to solutions obtained under independent and cooperative ordering, and under full information. The results show that while information asymmetry eliminates free-riding in the contributions game, the resulting aggregate contributions are not as high as under full information, leading to higher aggregate costs. 相似文献
994.
Abstract We study a nonlinear elliptic variational inequality associated with the combined stochastic control problem. By using the dynamic programming principle and the method of penalization, we establish the existence of a unique viscosity solution of the variational inequality and describe it as the value function of the corresponding combined stochastic game problem. 相似文献
995.
Abstract We study partially observable semi-Markov game with discounted payoff on a Borel state space. We study both zero sum and nonzero sum games. We establish saddle point equilibrium and Nash equilibrium for zero sum and nonzero sum cases, respectively. 相似文献
996.
Sajjad Aslani Khiavi Hamid Khaloozadeh Fahimeh Soltanian 《Mathematical and Computer Modelling of Dynamical Systems: Methods, Tools and Applications in Engineering and Related Sciences》2013,19(5):499-521
ABSTRACTWe study four-echelon supply chains consisting of manufacturer, wholesaler, retailer and customer with recovery center as hybrid recycling channels. In order to gain a larger market share, the retailer often takes the sales as a decision-making variable. For this purpose, in this supply chain, the retailer limits the forecast of market demand in future periods with expected logic. It also manages demand by leveraging prices and choosing market. In this paper, first, we investigate the state-space model of this supply chain system and examine the effect of complex dynamic and stochastic noise on the bullwhip effect. We analytically prove that this factor leads to the bullwhip effect. So, first, we filtered the information between nodes with extended Kalman filter after which we regulated the destructive effects of the bullwhip phenomenon by designing a non-linear quadratic Gaussian optimal controller. Eventually, the simulation results indicate the efficiency of the proposed method. 相似文献
997.
移动Ad-Hoc网络容量的稳定性是保证其服务质量的关键性质之一.本文提出一种新颖的考虑时变传播时延的非合作规划博弈移动Ad-Hoc网络容量分析模型稳定性控制技术.首先求得加入时变传播时延项的非合作规划博弈移动Ad-Hoc网络容量分析模型的源节点发送流量速率演化方程组—–一类非线性时变时滞微分方程组,在此基础上采用描述器技术结合线性矩阵不等式技术得到该模型的渐进稳定性准则,并设计了模型稳定性控制的迭代算法.由于是基于等价模型变换,所提出的渐近稳定性判别准则具有较小的保守性.仿真实验验证了本算法的有效性.本建模与分析方法虽以具体的非合作规划博弈移动Ad-Hoc网络容量分析模型为例,但其可以应用于一般的移动Ad-Hoc网络容量稳定性控制问题. 相似文献
998.
讨论基于提前期压缩的供应链利益协调问题。供应商采用批量分解方式向采购商供货,由3 PL承担运输。供应链成员通过提前期赶工压缩提前期,降低成本。基于斯坦克尔伯格博弈模型,设计一种决策原则,对采购商、供应商、3PL和系统四方成本节约情况进行比较并根据决策原则挑选出最佳方案。仿真分析讨论了相关参数变化对决策变量和各方成本节约额的影响。结论表明,三方博弈的结果倾向于选择A模式或D模式,且当采购商单位库存成本较大时,各方成本节约额随采购商订货成本变化波动较大。结论证明了基于提前期压缩的博弈决策方式的有效性。 相似文献
999.
1000.