具有Stark位移的非线性双光子Jaynes-Cummings模型

Two-photon Jaynes-Cummimgs model is generalized to the case of Kerr medium in this paper,The field and atom are prepared initially in two-photon superposition state and ground state respectively.Nonlinear coefficient affects the dynamic behaviors of the field and atom.Evolutions of the squeezing for the operators of field and atom and the quantum inversion are discussed.In particular,the higher-order squeezing for atomic dipole and the effects of nonlinearity on it,which have not been studied by other authors,are investigated,Increasing the nonlinear coefficient will decrease the squeezing depth of atomic dipole.     

在Kerr媒质中J-C模型的测量相位算符的涨落和压缩

By using the theory of measured phase operator proposed by Barnett and Pegg,dynamic properties of phase of a field are studied.The time evolution and squeezing of measured phase opoerators of a coherent field ineracting with a two-level atom in the cavity with or without the Kerr medium are investigated.The influences of virtual cavity field on squeezing of measured phase operator are studied.Our numerical results show that the squeezing effects are clearly influenced Kerr medium parameters,the field intensity,and the detuning.Moreover,the influence of the virtual-photon field makes more quantum noise in the evolution of measured phase opoerators.     

车灯表面质量分级装置

This paper introduces an installation for quickly classifying automobile‘s metal reflectors based on their roughness.The measuring principle and the mechanical structure are presented.Schematics of circuits and experimental results are given.Elimination and reduction of the effect of background lights or different bulbs on the measuring results are also described in detail.     

The conductance and polarization in quantum wires with Rashba and Dresselhaus spin-orbit interactions

The conductance and polarization are studied in one-dimensional ballistic quantum wire with both Rashba and Dresselhaus spin-orbit interactions.Two kinds of structures are considered in the present work,one with mixture of two interactions and the other with sequence structure of them.We find that the conductance and polarization are strongly affected by these two interactions.With both interactions we obtain a multi-peak contour of spin polarization and a dramatic oscillation pattern of spin conductance,which are due to the different combination of the two spin-orbit interactions.     

Free vibration of pre-tensioned nanobeams based on nonlocal stress theory

The transverse free vibration of nanobeams subjected to an initial axial tension based on nonlocal stress theory is presented. It considers the effects of nonlocal stress field on the natural frequencies and vibration modes. The effects of a small scale parameter at molecular level unavailable in classical macro-beams are investigated for three different types of boundary conditions： simple supports, clamped supports and elastically-constrained supports. Analytical solutions for transverse deforma- tion and vibration modes are derived. Through numerical examples, effects of the dimensionless nanoscale parameter and pre-tension on natural frequencies are presented and discussed.     

Energy Levels of Strong Coupling Magnetopolaron in Quantum Dot

By using variational method of Pekar type,we have studied the energy levels of strong coupling magnetopolaron in diskshape quantum dot(QD) and quantum well(QW),our esults show that ,with the increasing magnetic field and confinement strength,the magnetopolaron binding energy of QD and QW in the ground state and in the excited state is enhanced.The limiting results of bulk type and strict two-dimensional type are obtained.     

Optimal bandwidth scheduling of networked control systems （NCSs） in accordance with jitter

INTRODUCTION Compared with point-to-point control, the major advantages of networked control (NC) include flexi-bility of operation, integrated diagnostics, quick and easy maintenance and monitoring, small wiring volume, low cost. There are also many disadvantages due to the limited bandwidth resources shared by all nodes. Two major consequences are the net-work-induced delay and the jitter, the transmission fluctuations of successive instances of a data, both of which can degrade the dy…     

Study on spillover effect of copper futures between LME and SHFE using wavelet multiresolution analysis

Research on information spillover effects between financial markets remains active in the economic community. A Granger-type model has recently been used to investigate the spillover between London Metal Exchange(LME) and Shanghai Futures Exchange(SHFE) ,however,possible correlation between the future price and return on different time scales have been ignored. In this paper,wavelet multiresolution decomposition is used to investigate the spillover effects of copper future returns between the two markets. The daily return time series are decomposed on 2n(n=1,…,6) frequency bands through wavelet mul-tiresolution analysis. The correlation between the two markets is studied with decomposed data. It is shown that high frequency detail components represent much more energy than low-frequency smooth components. The relation between copper future daily returns in LME and that in SHFE are different on different time scales. The fluctuations of the copper future daily returns in LME have large effect on that in SHFE in 32-day scale,but small effect in high frequency scales. It also has evidence that strong effects exist between LME and SHFE for monthly responses of the copper futures but not for daily responses.     

Optimization of total harmonic current distortion and torque pulsation reduction in high-power induction motors using genetic algorithms

This paper presents a powerful application of genetic algorithm （GA） for the minimization of the total harmonic current distortion （THCD） in high-power induction motors fed by voltage source inverters, based on an approximate harmonic model. That is, having defined a desired fundamental output voltage, optimal pulse patterns （switching angles） are determined to produce the fundamental output voltage while minimizing the THCD. The complete results for the two cases of three and five switching instants in the first quarter period of pulse width modulation （PWM） waveform are presented. Presence of harmonics in the stator excitation leads to a pulsing-torque component. Considering the fact that if the pulsing-torques are at low frequencies, they can cause troublesome speed fluctuations, shaft fatigue, and unsatisfactory performance in the feedback control system, the 5th, 7th, 1 lth, and 13th current harmonics （in the case of five switching angles） are constrained at some pre-specified values, to mitigate the detrimental effects of low-frequency harmonics. At the same time, the THCD is optimized while the required fundamental output voltage is maintained.     

Study and Evaluation in CMOS Full Adders

Low power adder circuits ,SERF,10T-Ⅰ，10T-Ⅱ,10T-Ⅲ and a complementary adder (28T) at physical layout level are evaluated.Simulations based on the extracted adder circuit layouts are run to assess how various circuit setups can impact the speed and power consumption.In addition,impacts of output inveners on the circuit perfomance of modified SERF and 10T adders due to threshold loss problem are also examined.Differences among these adders are addressed and applications of these adders are suggested.     

介观电容耦合电路中的库仑阻塞和量子涨落

在电荷取分立值这一基本事实基础上,对介观电容介观电路进行了量子化,得到了该电路的有限差分形式的薛定谔方程。介观电路的量子效应不仅来源于电路的量子化,还来源于电荷的量子化,只有在考虑了电荷的量子化性质之后才有可能讨论介观电路中的库仑阻塞效应。经过幺正变换,薛定谔方程变为两个标准的马丢方程,利用WKBJ近似方法,讨论了介观电容耦合电路中电流在基态中的量子涨落,这是介观电路中量子噪声的主要来源。     

压缩真空态下介观复杂耦合电路的量子涨落

对介观复杂耦合电路量子化和哈密顿量对角化,研究了压缩真空态、真空态下回路中电荷和电流的量子涨落.结果表明,介观复杂耦合电路中存在电荷和电流量子涨落,这种量子涨落不仅与电路器件的参数、压缩因子、压缩角有关,而且还和彼此的互感耦合、耦合电容、耦合电感有关.     

不同状态下介观电路中量子涨落的比较

通过量子化有源RLC电路，研究了激发相干态、压缩真空态下介观电路的量子涨落以及电源对量子涨落的影响，并对不同状态下所得结果进行了比较。     

量子并行性及其应用

量子并行性是许多量子算法的一个基本特征,本文主要从矩阵论的思想出发阐述了量子并行性的原理及其应用,利用矩阵方法证明两种量子线路的输出结果和Deutsch算法。     

压缩真空态下介观电容耦合电路的量子涨落

提出了电容耦合电路的一种量子化方案,研究了在压缩真空态介观电路中电荷、电流的量子涨落,并对结果进行了讨论     

内外涨落效应对单一种群数量的影响

通过分析随机的佛霍尔斯特方程,讨论了内外涨落对单一物种演化的影响.即当涨落不可忽略,即使繁殖率小于死亡率,种群物种数量仍有可能保持在一个较小的规模.当增长率小于零,内涨落对物种数量的定态几率分布曲线的影响更明显;当增长率大于零,外涨落对物种数量的定态几率分布曲线的影响更显著.     

量子统计力学与有源介观RLC电路中的量子涨落

在电荷分立取值的客观事实基础上,利用介观电路的全量子理论,对含源介观RLC电路进行了量子化,得到了系统的有限差分薛定谔方程．在表象中,通过变换,薛定谔方程的形式变为标准的马丢方程．在WKBJ近似下,得到了源介观RLC电路的能级分布,进而计算了p和p^2在基态中的平均值．利用量子统计力学解决了有源介观RLC电路的量子涨落问题．     

介观含时RLC电路的新量子化方法及其量子涨落

根据电阻产生的物理机制即电子声子相互作用提出了RLC电路量子化的一种新方法 .用这一方法研究电路中的量子涨落比用传统有效哈密顿方法得到的结果要小 .同时还发现 ,如果电容和电感含有时间 ,则可在电路中产生压缩态 .本文方法克服了传统方法在时间很长后电荷和电流趋于零的不足     

Matlab在∑△调制器设计中的应用

分析了∑△调制器的工作原理及电路非理想特性对调制器性能的影响，应用Matlab对电路的非理想特性进行行为级描述，构建实际电路行为模型，以对∑△调制器设计性能进行有效评估。     

叠加相干态及其性质

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