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11.
需求信息泄露条件下供应链零售商订货策略研究   总被引:1,自引:0,他引:1  
针对供应链订货过程中的需求信息泄露现象,通过对比供应商在泄露信息和不泄露信息情况下的收益,研究了供应链需求信息泄露的产生机理。建立了需求信息泄露条件下订货过程中零售商之间的信号博弈模型,通过模型求解得到了分离均衡和混同均衡的存在条件,并对不同均衡状态下零售商的最优订货策略和最优收益进行了分析。在此基础上,进一步讨论了零售商的订货策略选择问题。最后,通过一个数值算例说明了有关结论的有效性。  相似文献   
12.
In this paper, we calculate the branching ratios for B^+→ Ds^+η, B^+→ Ds^+η′, B^+→ Ds^(→)η and B^+ → Ds^+η′ decays by employing the perturbative QCD (pQCD) factorization approach. Under the two kinds of η - η′ mixing schemes, the quark-flavor mixing scheme and the singlet-octet mixing scheme, we find that the calculated branching ratios agree well with the currently available experimental upper limits. We also consider the so called "fDs puzzle", by using two groups of parameters about the Ds^(→) meson decay constants, that are fDs = 241 MeV, fDs^→ = 272 MeV and fDs = 274 MeV, fDs^→ = 312 MeV, to calculate the branching ratios for the considered decays. We find that the results change 30%by using these two different kinds of paramters.  相似文献   
13.
翡翠为一种珍贵的玉石.不同品级的翡翠价值差异巨大,翡翠经充填、染色等处理以提高外观质量,并冒充天然翡翠.鉴别翡翠就显得非常必要.全面收集了市场上常见的A,B,C,不同颜色B+C货翡翠样品,在常规宝石学特征描述的基础上,进行了三维荧光光谱测试.三维荧光光谱技术是近年发展起来的一门新的荧光分析技术,该技术在宝石学方面还未得...  相似文献   
14.
Based on the assumption of two-quark structure of the scalar meson K*0(1430),we calculate the CP-averaged branching ratios for B→K0*(1430)η(') decays in the framework of the perturbative QCD(pQCD) approach here.We perform the evaluations in two scenarios for the scalar meson spectrum.We find that:(a) the pQCD predictions for Br(B→K*0(1430)η(')) which are about 10-5-10-6,basically agree with the data within large theoretical uncertainty;(b) the agreement between the pQCD predictions and the data in Scenario ...  相似文献   
15.
Within the framework of the perturbative quantum chromodynamics(PQCD) approach, we study the charmless two-body decays B → a1(1260)K*, b1(1235)K*. Using the decay constants and the light-cone distribution amplitudes for these mesons derived from the QCD sum rule method, we find the following results.(a) Our predictions for the branching ratios are consistent with the QCD factorization(QCDF) results within errors, but much larger than the naive factorization approach calculation values.(b) We predict that the anomalous polarizations occurring in the decays B→φK*, ρK*also happen in B→a1 K*decays, while they do not happen in B→b1 K*decays. Here the contributions from the annihilation diagrams play an important role in explaining the larger transverse polarizations in the B→a1 K*decays, while they are not sensitive to the polarizations for the B→b1 K*decays.(c) Our predictions for the direct C P-asymmetries agree well with the QCDF results within errors. The decaysˉB0→b1+K*-, B-→b10K*-have larger direct C P-asymmetries, which could be measured by the present LHCb experiment and the forthcoming Super-B experiment.  相似文献   
16.
以钛酸丁酯作为钛源,水为溶剂,乙酰丙酮(AcAcH)为表面修饰剂,采用微波水热辅助溶胶-凝胶法制备了纳米晶二氧化钛水溶液,利用提拉镀膜法在聚合物聚甲基丙烯酸甲酯(PMMA)基板上沉积得到了透明TiO2纳米晶薄膜.通过X射线衍射(XRD)、红外光谱(FTIR)、透射电子显微镜(TEM)、原子力显微镜(AFM)和紫外-可见光吸收光谱(UV-Vis)等对TiO2纳米颗粒和薄膜的晶相组成、表面形貌及光学性能进行表征.同时通过紫外光光催化降解罗丹明B研究了TiO2薄膜的光催化性能.结果表明:通过引入乙酰丙酮,可以得到高度分散、晶相为锐钛矿型的TiO2水溶胶,在PMMA基板上沉积得到的薄膜表面平整、致密,具有良好的透光率,经过180 min紫外光照射,对罗丹明B的降解率达到90;以上.  相似文献   
17.
针对现有LED太阳模拟器同时解决准直性、辐照度均匀性、光谱匹配性三大技术指标的难度较高的问题,基于光电一体化二次光学设计,提出一种简便、高效且可实现大功率的LED太阳模拟器光学系统设计方法。采用小角度准直透镜和抛物面镜来整合光源,通过混光棒和微结构进行匀光,最后利用抛物面镜实现光线的准直输出,基于同轴准直的设计思想完成LED太阳模拟器的设计。利用光学软件LightTools对LED太阳模拟器光学系统进行模拟仿真与分析优化,实验结果表明:在直径为260 mm的有效辐照面上辐照不均匀度为2.5%、准直角为1.5°。  相似文献   
18.
近年来,抗生素作为基本的治疗药物在医学、畜牧业、水产养殖业等方面被广泛应用,但其过量使用造成的抗生素残留问题也给生态环境、食品安全和人类健康造成严重的威胁.鉴于此,纳米电化学传感器在抗生素快速检测方面的研究成为热点,也取得了可观的进展.本文首先对抗生素进行了简单介绍,通过分析抗生素的电化学性质,综述了不同结构和类型的纳...  相似文献   
19.
By employing the perturbative QCD (pQCD) factorization approach, we calculate the full leading and the partial next-to-leading order (NLO) contributions to the seven B →πη(′) and η(′)η(′) decays. For B^+→ π+η(′) decays, the pQCD predictions for their decay rates agree very well with the data after the inclusion of the small NLO contributions. For neutral decays, the pQCD predictions are also consistent with the experimental upper limits and can be tested by the LHC experiments. The measured value of dir .Acp^dir(π+η)= 19±7% can also be accommodated by the pQCD approach.  相似文献   
20.
Based on the assumption of a two-quark structure of the scalar meson f0(980) ,we calculate the branching ratios and CP-violating asymmetries for the four B → f0(980) π and B → f0(980) η^(') decays by employing the perturbative QCD(pQCD) factorization approach. The leading order pQCD predictions for branching ratios are,Br(B^-→ f0(980) π^-) ~ 2.5×10^-6,Br(Bˉ^0 → f0(980) π^0) ~ 2.6×10^-7,Br(Bˉ^0 → f0(980) η) ~ 2.5×10^-7 and Br(Bˉ^0 → f0(980) η ) ~ 6.7×10^-7,which are consistent with both the QCD factorization predictions and the experimental upper limits.  相似文献   
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