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171.
研究了一类在贝叶斯需求预测更新情形下,生命周期中采用B2C与C2B两阶段进行产品销售的供应链模型,研究发现无法使用单一契约来协调供应链。在此基础上,设计了具有供应商价格折扣契约与零售商承诺订购契约的两阶段供应链契约协调机制,证明了两阶段协调机制能够实现供应链的帕累托改进。算例分析表明了两阶段契约协调机制的有效性,并发现能够实现供应链完美协调的契约参数不一定在帕累托集合内,供应链不一定能够达到完美协调;且由于零售商与供应商的最优契约参数不同,需要通过零售商与供应商之间的谈判达到纳什均衡。 相似文献
172.
《European Journal of Operational Research》2002,137(2):434-447
This paper studies the merger effect of two firms under the price competition of n firms, represented by n nodes on a linear network equilibrium model. The difference of profits between pre- and post-merger of the two firms can be described explicitly in terms of the substitution matrix. In general, the evaluation of the merger effect requires the knowledge of the substitution effects among all n nodes. For some interesting special cases, however, we obtain simple qualitative results. Specifically, the profitability of the merger can be predicted from the substitution effect of the two firms. Numerical examples exhibit the usefulness of our results. 相似文献
173.
《European Journal of Operational Research》2006,172(1):40-63
In this paper, we develop a framework for the modeling, analysis, and computation of solutions to multitiered financial network problems with intermediaries in which both the sources of financial funds as well as the intermediaries are multicriteria decision-makers. In particular, we assume that these decision-makers seek not only to maximize their net revenues but also to minimize risk with the risk being penalized by a variable weight. We make explicit the behavior of the various decision-makers, including the consumers at the demand markets for the financial products. We derive the optimality conditions, and demonstrate that the governing equilibrium conditions of the financial network economy can be formulated as a finite-dimensional variational inequality problem. Qualitative properties of the equilibrium financial flow and price pattern are provided. A computational procedure that exploits the network structure of the problem is proposed and then applied to several numerical examples. 相似文献
174.
《European Journal of Operational Research》2006,169(1):340-350
In this paper, we carry out parametric analysis as well as a tolerance limit based sensitivity analysis of a greedy heuristic for two knapsack problems—the 0–1 knapsack problem and the subset sum problem. We carry out the parametric analysis based on all problem parameters. In the tolerance limit based approach, we use a definition of the sensitivity analysis problem that is polynomial for polynomial heuristics. One of the interesting and counterintuitive results described in this paper is that the tolerance limits obtained from the heuristic sensitivity analysis cannot be used as bounds for the tolerance limits of the sensitivity analysis of optimal solutions in most cases. 相似文献
175.
《European Journal of Operational Research》2006,170(1):57-71
This investigation addresses a service inventory control problem in which a firm orders and sells a service which will be used or consumed by customers on a specific future date. The firm sells the product through an advance booking system, aiming to optimize product price to maximize the total expected profit. Considering situations in which product demand is price-dependent and customers with reservations may cancel advance orders, this work develops a continuous-time model to simultaneously determine the order quantity and selling prices. The analytical results reveal that the optimal ordering quantity and prices are derived via closed-form solutions. In addition, sensitivity analysis of the optimal prices with respect to the system parameters is also conducted to illustrate optimal decision characteristics. 相似文献
176.
网络交易中日益增长的欺诈行为阻碍了人们参与网上交易的积极性,激励参与方在网络交易中保持诚信交易是非常必要的。而目前电子商务网站中使用的在线信誉反馈系统难以实现激励卖方一直保持诚信交易。基于此,构建了基于交易时间价值的信誉反馈集结模型。理论模型表明:在生存期无限的情形下,只要历史交易信息对目前信誉度的影响足够小,卖方会保持持续的诚信交易。同时通过模拟分析比较了生存期有限的卖方在不同的历史信誉评价权重下的策略,卖方在不同的超额收益下的策略。分析表明:卖方从欺诈交易中获得的超额利润越大,卖方越不会保持诚信交易;基于交易时间价值的信誉反馈集结模型能够激励卖方保持持续的诚信交易行为。 相似文献
177.
178.
We analyze the strategic implications of consumers’ reference-price effects, either symmetric (for loss-neutral consumers) or asymmetric (for loss-averse consumers), in a differentiated oligopoly model where firms compete either in prices (à la Bertrand) or in quantities (à la Cournot) over an infinite time horizon. The dynamic game is specified in continuous time. The solution concept is Markov Perfect Equilibrium. We show how price dynamics in the presence of reference-price effects crucially depends on the nature of market competition. One of the main results of our analysis is that, with loss-averse consumers, there exists an interval of initial reference prices such that firms adopt the same constant-pricing strategy in both the Bertrand and the Cournot games, implying that the distinction between price and quantity competition has no impact on market conduct and performance. 相似文献
179.
Haejun Jeon 《European Journal of Operational Research》2021,288(3):1068-1084
We study a firm’s optimal decisions on investment, default, and financing when the amount of time and the running costs for project completion are uncertain. In the presence of time-to-build, a firm makes conservative investment and financing decisions; investment is delayed, and the optimal leverage ratio is inverted U-shaped with respect to the size of the lag. Although equity holders can choose to default before the project has been completed, the default probability in the presence of time-to-build is lower than that in the absence of a lag in most cases because of the conservative investment and financing decisions. Given the lower default probability, equity holders may benefit more from debt financing in the presence of time-to-build than they would in the absence of a lag. When firms can shorten their expected time-to-build by bearing more costs, unlevered firms strive to reduce the lag more than optimally levered firms do. However, highly levered firms utilize more resources to reduce the lag than all-equity firms do because equity holders are more concerned about the possibility of default before the project’s completion. 相似文献
180.
对于自然数i,d,k,n,0q(i:n,k,d)是一个基于有限域Fq上n维向量空间中子空间的相交关系的二元叠加码,研究了二元叠加码Mq(i:n,k,d)任意列之间的汉明距离,给出了它的检错性和纠错性. 相似文献