双重时序AR—MA模型的高价平稳性

本文讨论双重时序AR－MA模型的高价（4阶，8阶及一般2m阶）平稳解存在的充分条件，这些结论对建立模型参数的矩估计及讨论估计量的渐近性质都是必不可少的．     

Tunnelling-Induced Transient Gain in an Asymmetric Double Quantum Well

We investigate the transient behaviour of a weak probe in asymmetric double quantum well structures, where two excited states are coupled by resonant tunnelling through a thin barrier in a three-level system of electronic subbands. There is no external coherent coupling field applied, and we find that probe gain can be achieved during the transient process, which is induced by the coherent coupling of the upper states via the resonant tunnelling. We show that the transient behaviour of the probe depends on the coupling strength and the dephasing rate and can be tuned by changing the width of the tunnelling barrier.     

不对称有机合成和反应的分类

不对称有机合成和反应是制备对映纯化合物的方法之一,它具有广泛而不同的含义。对基于反应产物的“立体选择合成”,基于反应物的“立体辨别反应”和“去对称”以及基于不对称诱导方式的“代”分类方法作了介绍和评述。另外,对几个与不对称合成有关的制备对映纯化合物的方法也作了阐述。对“双重不对称合成”的立体化学,以Michael反应为例进行了讨论。参考文献34篇。     

基于双重态度模型的微表情与消费者购买决策的关系研究

以双重态度模型为理论基础,通过微表情与双重态度的相关关系,探讨微表情是否可以有效地预测消费者购买决策.通过分析40位有效被试行为实验得到的外显和内隐态度数据、购买决策数据,以及213,530张表情图片,研究发现:ST(眼部注意力停留时间比平均时间长)、AU14(收紧嘴角)、AU18(撅嘴)与内隐态度是显著相关的;ST、AU12(抬起眉毛整体)、AU7(眼轮匝肌内圈收紧)、AU14、AU18、AU24(嘴唇相互按压)与外显态度是具有相关性的;ST和AU14可以在一定程度上预测消费者购买决策.     

双重看涨期权定价的估计

在市场无套利、无摩擦和无风险利率为常数假定下,分别讨论了无红利配发和有红利配发情形时,一种新型期权—双重看涨期权的定价问题,主要利用套期保值策略对期权定价进行了若干估计,给出了上下界.     

Improved Performance by a Double-Insulator Layer in Organic Thin-Film Transistors

Organic thin film transistors based on pentacene are fabricated by the method of full evaporation. The thickness of insulator film can be controlled accurately, which influences the device operation voltage markedly. Compared to the devices with a single-insulator layer, the electric performance of devices by using a double-insulator as the gate dielectric has good improvement. It is found that the gate leakage current can be reduced over one order of magnitude, and the on-state current can be enhanced over one order of magnitude. The devices with double-insulator layer exhibit field-effect mobility as large as 0.14cm^2/Vs and near the zero threshold voltage. The results demonstrate that using a proper double insulator as the gate dielectrics is an effective method to fabricate OTFTs with high electrical performance.     

Optical Feedback Characteristics in He-Ne Dual Frequency Lasers

Optical feedback characteristics in He-Ne dual frequency lasers are studied systematically in different feedback power ratios with a variable attenuator. Feedback power ratios vary from 0.010 up to 0.998. Five distinct regimes of self-interference effects are found and defined as regimes Ⅰ, Ⅱ,Ⅲ,Ⅳand Ⅴ. Accordingly, five optical feedback levels have been put forward in He-Ne dual frequency lasers. Strong mode competitions are observed in regimes Ⅲ and Ⅳ. In regime Ⅴ, multiple feedback effects are investigated. The basic theoretical analysis is also presented. Our results can advance the research of self-mixing interferometer and displacement sensor of He-Ne orthogonally polarized dual frequency lasers.     

扩散Beddington-DeAngelis捕食食饵模型的行波解

主要研究捕食者和食饵皆具有一般密度制约的扩散Beddington-DeAngelis捕食-食饵模型的行波解.通过构造行波系统的Wazewski集和Lyaponov函数,应用拓扑打靶法的方法建立系统连结边界平衡点到共存平衡点的轨道,进而证明原扩散系统连结边界平衡点到共存平衡点的非负行波解的存在性.     

不确定变量序列的双重极限性

从不确定变量的公理化定义和不确定变量的基本极限性质出发,借助一般的极限定理思想,研究了不确定变量的双重极限理论.在不确定变量的几乎一致收敛性(u.s→)等价定义的基础上,讨论了几乎一致收敛(u.s→)与依测度收敛(M→)之间的嵌套定理,得到了较好的结果.     

双重道德风险下政府引导基金激励监督机制设计

在政府引导基金的运行中，两个代理人与引导基金的利益和追求的目标不一致，在信息不对称下都有可能发生道德风险，导致政策目标不能实现。为解决这一问题，本文在考虑双重道德风险的情形下，将激励机制、外部监督和惩罚机制结合起来，建立引导基金与两个代理人的三方博弈模型，并利用该模型研究控制和缓解代理人的道德风险的机制。研究发现：引入外部监督和惩罚机制能更有效地抑制基金管理机构的违约行为，促使其采取符合引导基金利益的行为，而且违约行为随着监督惩罚力度的增加而减少。对受托监督机构实行激励薪酬制可在一定程度上缓解其道德风险并提高其实施监督的积极性。对受托监督机构的激励强度与其风险厌恶程度，对基金管理机构的激励强度和基金绩效波动性成反比。同时监督成本和惩罚力度对最优激励强度具有重要的影响。本文研究证实了引入监督和惩罚机制对减少违约行为的有效性。同时对受托监督机构实行激励薪酬制有利于加强监管，确保政策目标的实现。研究结论可以为改进和完善政府引导基金的管理提供理论和政策指导。