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151.
Peng-Fei Duan Wei-Long Duan Qiong-Si Fu Min Tang Pei-Hua Chen 《International Journal of Theoretical Physics》2014,53(12):4402-4406
We propose a scheme to prepare a two-qubit remote entangled state based on four-qubit cluster state in cavity quantum electrodynamics which involves the interaction of the atoms with the cavity. Through using four-particle cluster state as a quantum channel, we shown that the probability and fidelity of the successful remote state preparation can approach unit. In addition, our protocol only need single qubit measurement instead of the conventional Bell-state measurement, then it is quite simple but also very robust to the cavity decay and the influence of the thermal field. 相似文献
152.
《Applied Mathematical Modelling》2001,25(9):775-792
In this study, the governing equations for large deflection of elastic thin shallow shells are deduced into an algebraic cubic equation to determine the unknown coefficient of the assumed deflection by applying Galerkin's method in combination with the algebraic polynomial and Fourier series. For the dynamic problem, the coefficient is replaced by an unknown function of time; after the same process is applied, the governing equations are deduced to be a nonlinear ODE of order two called the Duffing equation, and its analytical solution is known. The combination of the algebraic polynomial and Fourier series gives very rapid convergence in the asymptotic solutions. 相似文献
153.
范家参 《应用数学和力学(英文版)》2000,21(3):335-340
IntroductionThegoverningequationsforaninvertedelasticthinshallowshellonelastichafspaceinstaticbendingare[1]4-Eihi2kw=02=2/x2 2/y2,2k=ky(2/x2) kx(2/y2),(1)Di4w 2k=q-p,(2)w(x,y)=λe 2Ge4πGe(λe Ge)∫∫sp(ξ,η)dξdη(x-ξ)2 (y-η)2,(3)whereinEqs.(1),(2)and(3),w(x,y)isthedeflectionoftheshell,(x,y)isthem… 相似文献
154.
155.
Tao Yang Ruifen Liu Chunhua Zeng Weilong Duan 《Chinese Journal of Physics (Taipei)》2017,55(2):275-288
In this paper, we investigate the effects of time delay and non-Gaussian noise on the dynamics properties of the attractor network model of perceptual bistability. Using delay Fokker–Planck equation and projection operator method, the stationary probability distribution Pst(x), the associated relaxation time Tc, and the normalized correlation function C(s) for perceptual bistability are obtained, respectively. Research results show that: (i) the time delay τ and the correlation time τ0 from non-Gaussian noise can induce the change of the peaks in the Pst(x), i.e., the transition of the system appears; (ii) there exhibits an optimal value of the τ0 or τ by which the Tc or C(s) is maximum, this maximum shows the τ0 or τ first reduces the stability of the attractor network model of perceptual bistability in the steady state, and then enhances it; and (iii) the noise intensity P or departure q from the Gaussian noise only enhances the stability of the attractor network model of perceptual bistability in the steady state. 相似文献
156.
This paper aims to investigate the geodesic motion in the spacetime of a non-linear magnetic charged black hole surrounded by quintessence. By varying the Lagrangian corresponding to the metric, the orbital motion equation has been obtained. The effects of the magnetic charge $Q$, positive normalization factor $C$, angular momentum $b$, and energy $E$ on time-like and null geodesic motion are discussed from three aspects: orbital stability, orbital types, and circular orbits. By comparing the effects of the above parameters $C$, $b$ on the effective potential, it is found that quintessence has an impact on the types and stability of orbits. In addition, for time-like orbital motion, when $3.443113\leq b\leq6.392\,578$ (for fixed $C=0.0002$, $M = 1$, $Q=0.7$), there are bound orbits, and within this range, the stable circular orbits exist, and the radii of the innermost and outermost stable circular orbit are $r=5.912\,654$ and $r=56.745\,933$, respectively. For null orbital motion, the orbital types have only unstable circular orbit which occur at $r=2.951\,072$ ($E^{2}=E_{2}^{2}=0.4$), absorb orbits and escape orbits, but no stable circular orbits, and bound orbits. 相似文献
157.
Kevin D. Murphy 《Acta Mechanica Sinica》2012,28(1):190-200
Nonlinear dynamic response of nanomechanical resonator is of very important characteristics in its application. Two categories of the tension-dominant and curvature-dominant nonlinearities are analyzed. The dynamic nonlinearity of four beam structures of nanomechanical resonator is quantitatively studied via a dimensional analysis approach. The dimensional analysis shows that for the nanomechanical resonator of tension-dominant nonlinearity, its dynamic nonlinearity decreases monotonically with increasing axial loading and increases monotonically with the increasing aspect ratio of length to thickness; the dynamic nonlinearity can only result in the hardening effects. However, for the nanomechanical resonator of the curvature-dominant nonlinearity, its dynamic nonlinearity is only dependent on axial loading. Compared with the tension-dominant nonlinearity, the curvature-dominant nonlinearity increases monotonically with increasing axial loading; its dynamic nonlinearity can result in both hardening and softening effects. The analysis on the dynamic nonlinearity can be very helpful to the tuning application of the nanomechanical resonator. 相似文献
158.
在田间原位对烟叶成熟度进行判别,能够有效减少由于对成熟度判断错误而导致的烟叶损失率升高、质量下降的问题,而传统的人眼结合叶龄的田间成熟度判别方法缺少客观性,因此提出采用光谱特征参数结合支持向量机的方法对田间原位烟叶成熟度进行判别。以专家评定并在田间原位进行测量的五个成熟度等级共351个烟叶反射光谱作为试验样品,五个成熟度等级分别为M1,M2,M3,M4,M5。通过对反射光谱的分析发现,不同成熟度烟叶的光谱在可见光波段能够得到区分,而在近红外波段区分不明显,因此在可见光波段进行分析建模。分别采用可见光范围内的连续光谱(350~780 nm)、特征波段(496~719 nm)、光谱特征参数(绿峰幅值、绿峰位置、红边幅值、蓝边幅值、红边面积、蓝边面积、红边位置、蓝边位置)作为输入变量,采用支持向量机方法(supportvector machine,SVM)建立烟叶成熟度判别模型。结果表明,应用可见光光谱特征参数作为输入变量所建立的模型的正确识别率达到98.85%,而应用可见光连续谱、可见光特征波段作为输入变量的正确识别率分别为90.80%和93.10%。因此使用可见光光谱特征参数建立支持向量机的鲜烟叶成熟度判别模型对田间原位烟叶成熟度进行判别是可行的。 相似文献
159.
考虑非局部剪切效应的碳纳米管弯曲特性研究 总被引:2,自引:2,他引:0
基于Hamilton(哈密顿)变分原理和非局部连续介质弹性理论,建立了新型非局部Timoshenko(铁木辛柯)梁模型(ANT),推导了碳纳米管(CNT)的ANT弯曲平衡方程以及两端简支梁、悬臂梁和简支 固定梁的边界条件表达式,分析了剪切变形效应和非局部微观尺度效应对碳纳米管弯曲特性的影响.数值计算结果显示,碳纳米管的弯曲刚度随着小尺度效应的增强而升高.其次,这种小尺度效应对自由端受集中力的悬臂梁碳纳米管有明显作用,其刚度变化规律和其它约束条件的碳纳米管一样,这一点是ANT模型区别于普通非局部纳米梁模型的主要特点.经分子动力学模拟验证,ANT模型是合理分析碳纳米管力学特性的有效方法. 相似文献
160.
输液管道流固耦合非线性动力稳定分析 总被引:5,自引:0,他引:5
将弱约束输流管道非定常流液固耦合运动按波-流-振动系统建模成由4个非线性微分方程组成的分析模型,按模态进行分解研究系统在多种耦合状态下具有的运动稳定特性.以悬臂梁管道为例分析了耦合系统奇点的属性,得到了前四阶模态运动的相图.结果说明,多种耦合条件下输流管道的稳定性变得更为复杂,各阶模态运动具有不同的稳定特性. 相似文献