排序方式: 共有74条查询结果,搜索用时 109 毫秒
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考虑网络外部性和规模不经济的影响,对捆绑手机供应链的决策展开研究.构建了捆绑手机供应链的分散决策模型和集中决策模型,并对模型进行了比较分析.研究表明:1)规模不经济系数会阻碍系统利润的增长,而网络外部性系数促进系统利润的增长.2)手机制造商或电信运营商主导系统时所获利润远高于其不主导系统时的情形.同时手机制造商主导系统时,系统的利润要高于电信运营商主导系统时的利润.3)在分散决策下,手机制造商和电信运营商的利润均未达到最优:集中决策下,合约机套餐价格较低,总的销量更高,系统的利润更高.通过“补贴联合收益共享”协调契约,可以实现手机制造商和电信运营商的收益最大化. 相似文献
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Anomalous dynamics response of nonlinear elastic bar 总被引:1,自引:0,他引:1
IntroductionInresentyears,thechaoticbehaviorofbeamssubjectedtoperiodicloadbringsmoreandmorescholars’interests.In 1 983 ,FCMoonetal.[1]studiedthechaoticmotionsofbeamsinnonlinearboundaryconditions.In 1 994 ,S .AnanthaRamuandTSSankaretal.[2 ]analyzedbifurcationandCata… 相似文献
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The one-dimensional interacting Kitaev chain at half filling is studied. The symmetry of the Hamiltonian is examined by dual transformations, and various physical quantities as a function of the fermion-fermion interaction U are calculated systematically using the density matrix renormalization group method. A special value of interaction Up is revealed in the topological region of the phase diagram. We show that at Up the ground states are strictly two-fold degenerate even though the chain length is finite and the zero-energy peak due to the Majorana zero modes is maximally enhanced and exactly localized at the end sites. Here Up may be attractive or repulsive depending on other system parameters. We also give a qualitative understanding of the effect of interaction under the self-consistent mean field framework. 相似文献
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In the paper the nonlinear dynamic equation of a harmonically forced elliptic plate is derived, with the effects of large
deflection of plate and thermoelasticity taken into account. The Melnikov function method is used to give the critical condition
for chaotic motion. A demonstrative example is discussed through the Poincaré mapping, phase portrait and time history. Finally
the path to chaotic motion is also discussed. Through the theoretical analysis and numerical computation some beneficial conclusions
are obtained.
Foundation item: the National natural Science Foundation of China (19672038); the Natural Science Foundation of Shanxi Provence (1880342). 相似文献
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页岩强度是页岩油气开发所必需的基础技术参数之一,对页岩强度的研究贯穿于钻完井、压裂工艺施工的全过程.常规宏观室内实验存在试样获取困难、耗时较长,受井下工矿制约,地球物理方法获取资料品质欠佳且增加了井下设备卡、埋风险.因此,提出基于均匀化理论评价页岩微观多孔黏土强度的方法,进行多孔黏土组成与力学分析.基于耗散能原理和Drucker-Prager准则,开展了微观多孔黏土的强度与$\pi$函数的应变求解分析;讨论黏土颗粒与粒间孔隙的力学特性,建立多孔黏土的均匀化应变能;采用强度均匀化理论构建微观非线性函数模型,建立与多孔黏土组成、摩擦系数、内聚系数等参数相关的均匀化函数模型;基于纳米力学实验、量纲分析和有限元模拟,分析多孔黏土硬度、强度与组成的内在关系.研究结果表明,页岩微观多孔黏土的弹性模量和硬度与黏土堆积密度正相关,当黏土堆积密度一定时,硬度与内聚系数的比值受摩擦系数影响较大,为非线性递增;通过量纲分析和有限元模拟,求解页岩微观多孔黏土关于硬度--强度--堆积密度的$\pi$函数,揭示页岩微观黏土矿物的组成与力学性质的关系,为进一步深入研究页岩细观强度参数和宏观强度预测奠定基础. 相似文献