隧穿量子点分子模型与光场相互作用的熵特性

用全量子论研究了微腔中量子化光场与隧穿量子点分子模型相互作用系统的熵特性,导出了量子点系统熵（场熵）的计算公式,讨论了不同的初始光场对量子点系统熵（场熵）的影响。结果表明：初始光场处在相干态情况下,随着失谐量△的增大,场熵的周期明显加强,但场熵的均值却不断减小,这表明失谐量的增加,导致光场与量子点分子的关联减弱,即耦合程度降低;在初始光场为压缩真空态的情况下,其结论与初始光场为相干态情况下的结论相似。     

生长模型在地基沉降全过程预测中的应用

地基的全过程沉降量与时间的关系呈S形曲线,可以用Logistic、Von Bertalanffy和Gompertz三种非线性生长模型来描述。结合工程实例预测地基沉降,三种曲线的拟合度均在0.99以上。     

16V280ZJA型机车柴油机组合活塞弹性接触研究

本文以 1 6V2 80 ZJA柴油机的钢顶球铁裙组合活塞为研究对象 ,建立其三维有限元弹性接触模型。在最大气体爆发压力工况下 ,对活塞在应用不同的接触间隙时呈现出的不同应力分布规律进行分析并与实验结果进行对比 ,以确定活塞受力的薄弱环节 ,为改进组合活塞的结构设计提供了依据     

Von Willebrand因子在先天性心脏病肺动脉高压中的表达及意义

目的　探讨VonWillebrand因子 (VWF)在先天性心脏病 (简称先心病 )室间隔缺损 (简称室缺 )伴肺动脉高压 (简称肺高压 )中的表达及其临床意义。方法　应用酶联免疫吸附双抗体夹心法检测 1 5例先心病室缺伴肺高压患者血浆中VWF的表达 ,并与先心病室缺无肺高压的患者作对照。结果　伴肺高压的先心病患者血浆中的VWF水平显著高于无肺高压的先心病患者(P <0 .0 5 )。结论　VWF与先心病室缺伴肺高压的发生、发展有着密切关系。     

Energy analysis of the Von Schlippe tyre model with application to shimmy

Shimmy is an engineering example of self-excited vibrations. Much research on shimmy has considered the tyre as a positive feedback or negative damping to introduce instability of the entire system. In this context, we focus on the behaviour of the tyre under periodic excitations. The Von Schlippe tyre model is selected and the energy flow method is applied to illustrate the energy transfer by the tyre during shimmy. The energy flow method evaluates the tyre performance with a prescribed sinusoidal motion and provides a novel evaluation method for tyre models. With the help of straight contact line assumption in the Von Schlippe tyre model, the relative motion between the contact line and the wheel centre is studied to understand the path dependency of the energy transfer. It turns out that the tyre is extracting energy from the forward motion to induce unstable lateral and yaw vibrations when the motion or orientation of the contact line has a phase lead with respect to the wheel centre.