产需不确定下面向资金约束供应商的供应链融资策略研究

以包含一个供应商和一个分销商的供应链为研究对象,其中分销商面临市场需求不确定性,供应商存在资金约束且面临产出不确定性。 提出期望利率的概念,研究银行贷款期望利率一定的情况下,供应链银行融资最优策略。 构建了供应链预付款融资机制,在此基础上研究预付款模式下供应链的融资与生产订购的最优策略,并讨论了预付款期望利率的可行范围。 研究表明,预付款融资模式下,分销商愿意以低于银行贷款利率的期望利率向供应商提供预付款; 存在预付款期望利率可行区间,实现预付款协调模式下供应链系统的帕累托改进。     

基于创新性过程投入的员工创造力影响因素研究

创新性过程投入是近年来在管理领域出现的新概念,虽然从理论上能够推导出这一概念有助于员工创造力的提升,但其在知识工作者的内生动机与创造力之间是否以及扮演什么角色,理论界触及不深、缺乏系统的探索和阐释。论文基于自主理论建构了一个被调节的中介效应模型,旨在探索内生动机是如何影响员工创造力的。实证结果表明:(1)知识工作者的内生动机显著影响创造力;(2)创新性过程投入在知识工作者内生动机与创造力之间起部分中介作用;(3)创造力自我效能感调节了创新性过程投入对创造力的影响;进一步,(4)创新性过程投入的中介作用受到了创造力自我效能感的调节,创造力自我效能感程度越高,知识工作者内生动机通过创新性过程投入对创造力的间接作用越强。研究发现创新性过程投入在主效应中的特殊解释力,丰富内生动机效力的相关研究,对员工创造性实践提供了有益的启示。     

乘客策略行为下考虑需求学习的航空客运动态定价策略研究

研究航空公司在需求学习下的动态定价策略。通过假设乘客到达率不确定以及具有策略等待行为,运用贝叶斯理论和博弈论对航空公司需求学习下的多周期动态定价问题进行建模,探讨了机票最优定价策略的充分条件,并通过分析航空公司收益函数的性质,得到了最优定价随时间和已出售机票数量的变化趋势。最后应用算例分析了需求学习的效果,得出:需求学习能够缓解需求不确定带来的损失,但不能完全消除;乘客策略程度越大,需求学习效果越明显。     

无容量限制设施选址问题的降阶回溯算法

无容量限制设施选址问题(uncapacitated facility location problem, UFLP)是经典组合优化中NP-Hard问题之一,在诸多领域具有广泛的应用价值。本文首先研究UFLP的数学性质,并进行了数学证明。运用这些数学性质不仅可以确定某些设施必定开设或者关闭,还可以确定某些连接边是否在服务集中,从而缩小问题的规模,加快求解速度;在此基础上设计出一个新的基于上下界的回溯算法来求解UFLP。最后,通过一个示例进一步阐述该算法的原理,结果表明该算法具有明显的可行性和有效性。     

Photoluminescence and X-Ray Photoelectron Spectroscopy of p-Type Phosphorus-Doped ZnO Films Prepared by MOCVD

Reproducible p-type phosphorus-doped ZnO （p-ZnO：P） films are prepared on semi-insulating InP substrates by metal-organic chemical vapour deposition technology. The electrical properties of these films show a hole concentration of 9.02 × 10^17 cm ^-3, a mobifity of 1.05 cm^2 /Vs, and a resistivity of 6.6 Ω.cm. Obvious acceptorbound-exciton-related emission and P-induced zinc vacancy （Vzn） emission are observed by low-temperature photoluminescence spectra of the films, and the acceptor binding energy is estimated to be about 125meV. The local chemical bonding environments of the phosphorus atoms in the ZnO are also identified by x-ray photoelectron spectra. Our results show direct experimental evidence that Pzn-2Vzn shallow acceptor complex most likely contributes to the p-type conductivity of ZnO：P films.     

Crystal Structure and Magnetic Properties of Sm2 Fe17-Nδ Thin Films Deposited on Si （100） Substrates

This work focuses on the crystal structure and magnetic properties of the hard magnetic Sm2 Fe17 Nδ films prepared by dc magnetron sputtering and the subsequent nitriding process. The XRD, EDS, M-H and M-T data show that N enters the cell structure and the films with the single Th2Zn17 phase are obtained when the nitriding temperature varies from 300 to 400℃, thus the maximum value of the coercivity Hc reaches 2561.7Oe. However, the Sm2Fo17 phase decomposes to the StuN nonmagnetic phase and the α-Fe soft magnetic phase with further increasing nitriding temperature, which corresponds to the decreasing Hc. Furthermore, the easy magnetization direction （EMD） is found to locate randomly in the film plane. This texture can not give an excellent MR/Ms higher than the Stoner-Wohlfarth limitation （MR/Ms = 0.5）, which agrees well with the observed low MR/Ms （0.58）. It is suggested that the magnetization reversal process is dominated by the nucleation mechanism according to the initial magnetization curve and the dependence of Hc on the field H.     

An Extension of the Two-Dimensional JKR Theory to the Case with a Large Contact Width

In the Hertz and JKR theories, parabolic assumptions for the rounded profiles of the sphere or cylinder are adopted under the condition that the contact radius （width） should be very small compared to the radius of the sphere or
cylinder. However, a large contact radius （width） is often found in experiments even under a zero external loading. We aim at extending the plane strain JKR theory to the case with a large contact width. The relation between the external loading and the contact width is given. Solutions for the Hertz, JKR and rounded-profile cases are compared and analyzed. It is found that when the ratio of a/R is approximately larger than about 0.4, the parabolic assumptions in the Hertz and JKR theories are no longer valid and the exact rounded profile function should be used.     

Comparison of Nd:YAG Ceramic Laser Pumped at 885nm and 808nm

Laser performance of 1064 nm domestic Nd：YAG ceramic lasers for 885 nm direct pumping and 808 nm traditional pumping are compared. Higher slope efficiency of 34% and maximum output power of 16.5 W are obtained for the 885nm pump with a 6ram length 1 at.% Nd：YAG ceramic. The advantages for 885nm direct pumping are discussed in detail. This pumping scheme for highly doping a Nd：YAG ceramic laser is considered as an available way to generate high power and good beam quality simultaneously.     

Hawking radiation as tunneling and the unified first law of thermodynamics at the apparent horizon of the FRW universe

Relations between the tunneling rate FRW universe are investigated. The namics in such a dynamical system. first law of thermodynamics through and the unified first law of thermodynamics at the apparent horizon of the tunneling rate arises as a consequence of the unified first law of thermodyAnalysis shows how the tunneling is intimately connected with the unified the principle of conservation of energy.     

Light Localization in Slot Photonic Crystal Waveguide

A single-mode photonic crystal waveguide with a linear tapered slot is presented, which can localize light spatially by changing the slot width. Its effective bandwidth is 52nm, from 1500nm to 1552nm. Along the tapered structure, the slot width is reduced, and the corresponding band curve shifts. The group velocity of light becomes zero at the band edge. Therefore, different frequency components of the guided light are slowed down and finally localized at correspondingly different widths inside a tapered slot photonic crystal waveguide. Furthermore, this structure can confine light wave in a narrow slot waveguide, which may effectively enhance the interaction between light and the low-index wave-guiding materials filled in the slot.