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71.
刘军  谭德庆  李良  谢会芹 《运筹与管理》2017,26(10):112-120
在竞争环境下,探讨议价能力对产品定位-价格决策、成员利润、用户以及社会整体的影响,采用稳定性分析法研究均衡状态下的渠道结构分布,并对基本模型进行拓展分析。研究表明:生产商议价能力越强,产品批发/零售价格和渠道成员利润越高,零售商在筛选产品生产商时更愿意选择知名品牌;采用自营模式将提高消费者剩余和社会福利;成本差异的扩大将提高社会福利,而用户偏好不确定性虽然有助于提升上下游成员利润,但会损害社会整体利益。  相似文献   
72.
本文对无圈图博弈进行了研究,考虑了大联盟收益不小于各分支收益之和的情况。通过引入剩余公平分配性质,也就是任意两个分支联盟的平均支付变化相等,给出了一个基于平均树值的无圈图博弈有效解。同时,结合有效性和分支公平性对该有效解进行了刻画。特别地,若无圈图博弈满足超可加性时,证明了该有效解一定是核中的元素,说明此时的解是稳定的。最后,通过一案例分析了该有效解的特点,即越大的分支分得的剩余越多,并且关键参与者,也就是具有较大度的参与者可获得相对多的支付。  相似文献   
73.
聂佳佳  林晴 《运筹与管理》2016,25(6):274-281
在考虑消费者低碳偏好的情形下,建立了一个大企业作为领导者与多个小企业之间的博弈模型。在小企业生产普通产品情形下,研究了大企业低碳产品选择策略。研究发现:当小企业对称时,较大的碳减排量会促使大企业生产低碳产品以获得较高的零售价格,且小企业在大企业选择普通产品时有较高的销量;大企业制造商是否生产低碳产品取决于小企业的个数、消费者对小企业产品的认可度以及低碳产品低碳减排量的综合影响。当小企业不对称时,较少的小企业数量会促使大企业选择生产普通产品,而小企业数量较多时,大企业会生产低碳产品。  相似文献   
74.
In the current paper we examine a game-theoretic setting in which three countries have established a regional organization for the conservation and management of straddling and highly migratory fish stocks. A characteristic function game approach is applied to describe the sharing of the surplus benefits from cooperation. We demonstrate that the nucleolus and the Shapley value give more of the benefits to the coalition with substantial bargaining power than does the Nash bargaining scheme. We also compare the results that are obtained by using the nucleolus and the Shapley value as solution concepts. The outcomes from these solution concepts depend on the relative efficiency of the most efficient coalition. Furthermore, the question of fair sharing of the benefits is considered in the context of straddling stocks.  相似文献   
75.
Based on a simple outranking method of multi-attribute decision making (MADM), called Dichotomy-Cut, developed in recent years and published elsewhere, this paper describes how to reliably elicit the necessary decision knowledge for implementing various decision modes via this method and its computerized support - UNIDAS 2. The most important features of this method are outlined, namely, how to compose the preference ordered matrices and which are the basic decision rules. Special attention should be paid to specific interactive group decision behaviour of experts. Two examples plainly explain the contents discussed.  相似文献   
76.
Summary Mutual binding between a ligand of low molecular weight and its macromolecular receptor demands structural complementarity of both species at the recognition site. To predict binding properties of new molecules before synthesis, information about possible conformations of drug molecules at the active site is required, especially if the 3D structure of the receptor is not known. The statistical analysis of small-molecule crystal data allows one to elucidate conformational preferences of molecular fragments and accordingly to compile libraries of putative ligand conformations. A comparison of geometries adopted by corresponding fragments in ligands bound to proteins shows similar distributions in conformation space. We have developed an automatic procedure that generates different conformers of a given ligand. The entire molecule is decomposed into its individual ring and open-chain torsional fragments, each used in a variety of favorable conformations. The latter ones are produced according to the library information about conformational preferences. During this building process, an extensive energy ranking is applied. Conformers ranked as energetically favorable are subjected to an optimization in torsion angle space. During minimization, unfavorable van der Waals interactions are removed while keeping the open-chain torsion angles as close as possible to the experimentally most frequently observed values. In order to assess how well the generated conformers map conformation space, a comparison with experimental data has been performed. This comparison gives some confidence in the efficiency and completeness of this approach. For some ligands that had been structurally characterized by protein crystallography, the program was used to generate sets of some 10 to 100 conformers. Among these, geometries are found that fall convincingly close to the conformations actually adopted by these ligands at the binding site.  相似文献   
77.
We consider the problem of optimal risk sharing in a pool of cooperative agents. We analyze the asymptotic behavior of the certainty equivalents and risk premia associated with the Pareto optimal risk sharing contract as the pool expands. We first study this problem under expected utility preferences with an objectively or subjectively given probabilistic model. Next, we develop a robust approach by explicitly taking uncertainty about the probabilistic model (ambiguity) into account. The resulting robust certainty equivalents and risk premia compound risk and ambiguity aversion. We provide explicit results on their limits and rates of convergence, induced by Pareto optimal risk sharing in expanding pools.  相似文献   
78.
In several literature reports biuret and its sulfur analogs are reported to exist in their diketo form with general formula H2N? CX? NH? CY? NH2 (X = O, Y = O, biuret; X = Y = S, dithiobiuret; and X = O, Y = S, thiobiuret). On the other hand, recently reported results on the electronic structure of biguanide analogs (X = Y = NH)demonstrated that a form equivalent to diketo is not the preferred structure. Thus, a systematic ab initio study on the tautomeric preferences of biuret and its sulfur analogs (dithiobiuret and thiobiuret) has been carried out. The results indicate that an interplay of conjugative stabilization and intramolecular hydrogen bonding to play a role in tautomeric preferences. Energy and geometric parameters, natural bond orbital analyses have been employed to understand the chemistry of the title compounds. The results indicate that unlike biguanides, these compounds prefer diketo forms containing hydrogen on the bridging nitrogen (N4) and in a trans‐arrangement (1a–4a). However, tautomerization of these keto forms to the corresponding enol isomers was also found to be highly probable. © 2008 Wiley Periodicals, Inc. Int J Quantum Chem, 2008  相似文献   
79.
The goal programming (GP) model has been utilized for designing a quality control system (QCS) where several features are simultaneously considered. In the context of the quality control, the parameters can be imprecise and expressed through intervals. The aim of this paper is to propose two formulations for designing a QCS based on the imprecise GP model. The concept of satisfaction functions will be utilized to integrate explicitly the decision-maker’s preference. The developed formulations are illustrated through an example of a paper factory.  相似文献   
80.
The low efficiency of detectors in all EPR experiments with optical photons makes the use of the fair sampling assumption unavoidable. This assumption is reputed to be both reasonable and impossible to test experimentally. We argue that there is, in fact, little evidence supporting the fair sampling assumption, and we propose an experiment capable of putting this crucial hypothesis to a test.  相似文献   
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