Strong Correlation of Fluorescence Photons without Quantum Interference

It has been predicted that a driven three-level V atom can emit strongly correlated fluorescence photons in the presence of quantum interference. Here we examine the effects of quantum interference on the intensity correlation of fluorescence photons emitted from a driven three-level A atom. Unexpectedly, strong correlation occurs without quantum interference. The quantum interference tends to reduce the correlation function to a normal level. The essential difference between these two cases is traced to the different effects of quantum interference on coherent population trapping （OPT）. For the V atom, quantum interference and coherent excitation combine to lead to OPT. For the A atom, however, the quantum interference tends to spoil OPT while the coherent excitation induces the effect.     

The relationship between acoustic radiation modes and structural modes and its applications

Both acoustic radiation modes and structural modes play an important role in the field of structure-borne sound, however, little work has been done for inherent relations between these two kinds of modes. This paper is focused on the relationship between the radiation modes and structural modes and its physical mechanisms. First, a governing equation for relating the radiation mode and structural mode is given based on the characteristics of the modes. Then, using the symmetric or anti-symmetric properties of two kinds of modes, the corresponding relations are presented. And then, numerical examples are given to verify the theoretical investigations, and it has been shown that, for a simply supported rectangular panel vibrating at low frequencies, the first radiation mode is dominant corresponding to (odd, odd) structural modes; the following radiation modes are respectively dominant corresponding to (even, odd), (odd, even), and (even, even) structural modes. Finally, such relations are applied to active acoustic structural control and provide a direct help for the design of active control strategy and arrangement of the secondary forces.     

证券创新三条主线

目前证券公司仍存在严重的业绩波动与同质化竞争，解决之道在于证券创新。 考查《十二五规划纲要》，其中已描绘了金融创新的远景蓝图。不过，对于2011年的金融创新，《政府工作报告》中的表达显得含蓄与笼统，这决定了未来将是一个谨慎与渐进的过程，诸多金融创新的推出需要相时而动。2011年，证券市场将在已有创新基础上进一步扩容与深化，并且会集中在融资融券等方面，具体包括增加标的证券范围、放松投资者准入、推出第四批试点券商并将业务常规化，以及新三板扩容等。     

基于性能的直流电机系统未知推力波动的自适应补偿控制

针对一类直流电机系统,设计基于性能的未知推力波动的自适应补偿控制器.由于推力波动中含有非线性化的未知参数,因此无法利用常规的自适应方法,通过直接估计这些参数对其影响进行补偿.根据未知推力波动的结构特性,基于Lipshitz条件引入推力波动项的放大技术,设计其内部非线性化未知参数的自适应估计律,精确补偿其影响,从而避免了简单的把波动看作未知扰动所造成的系统性能的损失.有别于现有模型,在模型变换中并未忽略微小等效电感的影响,使得系统模型更具一般性.仿真结果表明该自适应控制器可有效补偿推力波动的影响,实现对指令信号的高精度快速跟踪且具有较强的抗干扰性和鲁棒性.     

一类非线性退化波动方程解的爆破

考虑了有界区域上一类非线性退化波动方程的初边值问题.通过改进Vitillaro,Li和Tsai的方法,建立了非正的初始能量以及正的初始能量下解的爆破结果.同时,还给出了解的生命跨度估计.     

LOCAL WELL-POSEDNESS AND ILL-POSEDNESS ON THE EQUATION OF TYPE □u = u^k（δu）^α

This paper undertakes a systematic treatment of the low regularity local wellposedness and ill-posedness theory in H^s and H^s for semilinear wave equations with polynomial nonlinearity in u and δu. This ill-posed result concerns the focusing type equations with nonlinearity on u and δtu.     

三元复合体系油水界面张力与乳化程度关系研究

通过用不同界面张力体系和原油进行乳化实验,制备出一系列不同数量级的界面张力值和不同乳化效果的样品。并且考察了样品界面张力性能和乳化性能的对应关系。研究了界面张力性能和乳化程度的关系。     

THE EXPONENTIAL STABILIZATION FOR A SEMILINEAR WAVE EQUATION WITH LOCALLY DISTRIBUTED FEEDBACK

This paper considers the exponential decay of the solution to a damped semilinear wave equation with variable coefficients in the principal part by Riemannian multiplier method. A differential geometric condition that ensures the exponential decay is obtained.     

金属氧化物半导体场效应管热载流子退化的1/fγ噪声相关性研究

研究了金属氧化物半导体(MOS)器件在高、中、低三种栅压应力下的热载流子退化效应及其1/fγ噪声特性.基于Si/SiO2界面缺陷氧化层陷阱和界面陷阱的形成理论,结合MOS器件1/f噪声产生机制,并用双声子发射模型模拟了栅氧化层缺陷波函数与器件沟道自由载流子波函数及其相互作用产生能级跃迁、交换载流子的具体过程.建立了热载流子效应、材料缺陷与电参量、噪声之间的统一物理模型.还提出了用噪声参数Sfγ表征高、中、低三种栅应力下金属氧化物半导体场效应管抗热载流子损伤能力的方法.根据热载流子对噪声影响的物理机制设计了实验并验证这个模型.实验结果与模型符合良好.     

谈谈ν=νλ中的ν

本文指出，在波长、频率与波速的关系式ν＝νλ 中，ν是波的频率，不应看作波源的振动频率．两者只 有数量上的关系而不是同一概念．本文兼谈多普勒效 应的教学问题，以加深对ν的理解．