查询词典 perturbation parameter

The eigenvalue problem of Dirac operator with perturbation Parameter is studied,the analyticity of perturbation parameter is discussed,and the analytic extension is done,at last,the expansion formulas of power serier about preradical expansion into perturbation parameter are got.

针对带有微扰参数的Dirac算子特征值问题，讨论了对微扰参数的解析性，并进行了解开拓，最后得到了预解核对微扰因子的幂级数展开式。

First make the subjects give either right or wrong responses to the same question with different b value. When estimating the abilities of the subjects with the use of one-parameter or two-parameter Logistic model, it is found that there exists two kinds of unfits.(2) Estimate the abilities of the subjects after introducing c parameter on the basis of the two-parameter model. The first unfit can be rectified. However, the second unfit still exists and the third unfit appears.(3) Then estimate again after introducing y parameter. It is discovered that the second unfit is rectified, but the first unfit still exists and the fourth unfit appears.(4) Form Logistic four-parameter model by introducing c parameter and y parameter at the same time and estimate one more time. This model makes all kinds of unfits, including the first, second, third and fourth unfits, rectified.

1设计这批被试分别做对或做错一道b值不同的试题，用Logistic单、双参数模型对被试进行能力估计时，发现被试能力估计存在着两类失拟现象；(2)在双参数模型基础上增加c参数，对被试进行能力估计，发现c参数能有效纠正第一失拟现象，然而仍然存在第二失拟现象，同时还存在第三失拟现象；(3)在双参数模型基础上增加γ参数，再对被试进行能力估计，发现γ参数能有效纠正第二失拟现象，而仍然存在第一失拟现象，同时还存在第四失拟现象；(4)同时增加c、γ参数形成Logistic四参数模型，再对被试进行能力估计，这时该模型对各类失拟现象，包括第一、第二、第三、第四失拟现象都具有良好拟合能力。

Chapter four studies the chaotic responses in a system consisting of simple pendulum and harmonic oscillator under bounded noise excitation. Firstly, the Melnikov function of the two-degree-of-freedom system under Hamiltonian perturbation is derived. The essential condition of the autonomous system for the probable onset of chaos is obtained, the Poincare maps of the system under small Hamiltonian perturbation and the effect of increasing perturbation on the Poincare maps are studies. Then for the non-autonomous system under damping and harmonic or bounded noise excitation, the largest Lyapunov exponent and Poincare maps are calculated. From the analysis of the largest Lyapunov exponent, the critical criterion for the onset of chaos, and the conclusion that the threshold of bounded noise amplitude for the onset of chaos in the system increases as the intensity parameter of Wiener process increases are obtained. The result from the analysis of Poincare maps is in agreement with that obtained from the Largest Lyapunov exponent. The effect of varying damping coefficient and intensity parameter of Wiener process is also analyzed.

第四章研究了有界噪声激励下的两自由度单摆—谐振子系统的混沌运动，首先推导了该两自由度系统仅在Hamilton扰动下的Melnikov函数，得到该自治系统可能产生混沌的必要条件；研究了该系统在小的Hamilton扰动和增大摄动情形下的Poincare截面；然后对有阻尼、谐和或有界噪声激励下的非自治系统数值计算了其最大Lyapunov指数和Poincare截面；从Lyapunov指数分析得到了这个两自由度系统产生混沌运动的临界条件及产生混沌的临界激励幅值随Wiener过程强度参数值的增大而增大的结论，Poincare截面分析的结果亦符合Lyapunov指数分析的结论；研究了Wiener过程强度参数、阻尼系数变化对Poincare截面的影响。

The dose enhancement effects and decreasing effects caused by material inhomogeneity were studied quantitatively with a parameter named Dose Perturbation Factor, which was the ratio of the dose at a point in the heterogeneous phantom to the dose of the same spatial location point in the homogeneous phantom. It was showed that the degrees of the dose enhancement or decreasing depended on the energy of radiation, field sizes of the beamlets and compositions of the media. The dose perturbation for high energy X rays is greater than that for low energy X rays. At the same energy condition, the dose perturbation decreased when the field size increased. And the relationship between them was not linear.

模拟结果表明：在小射野情况下，异质组织界面处出现了较大的剂量跃变，剂量扰动效应的强弱程度取决于射线的能量、射野的大小和模体介质的不同等多种因素，高能X射线条件下的剂量扰动效应大于低能X射线条件下的剂量扰动；在入射X射线能量相同的条件下，剂量扰动效应随射野尺寸的减小而增强，并呈现一种非线性关系。

And the channel composed of the new radio induction system for communication is different from the parameter-constant channel and the traditional parameter-changing channel, its parameter is decided by the mutual induction between its antenna and induction-cable, by the location of its antenna, by the signal frequency passing through, its parameter has nothing to do with the time parameter. The channel composed of the new radio induction system is a new parameter-changing channel independently of time for communication.

而且，由新型无线感应系统组成的信道既不是恒参信道，也不是一般目前所知的变参信道，其信道传递函数的幅值只与信号的频率有关，与系统中天线和感应电缆之间的互感和天线的位置有关，而与时间无关，其信道传递函数的相位只与天线的位置有关，而与时间无关，由新型无线感应系统组成的信道是一种不随时间变化的新型变参信道。

Some conclusions are obtained:(1) The interval data concept can rationally settle the apart component's dependence problem of monitoring data;(2) The survey point's displacement which is the material parameter's increasing function or deducing function can be used to back-analyse the material parameter's up and down limit; and (3) Both the interval parameter perturbation back analysis method and the interval parameter monotony back analysis method can obtain satisfactory interval parameters.

通过分析得出结论：(1)可利用区间数概念合理解决监测资料中分离分量相关性的问题；(2)可利用工程结构中位移为待反分析材料参数的增函数或减函数的测点位移的上、下限，来反演得到不确定性材料参数的上、下限；(3)工程算例分析表明，区间参数摄动优化反分析法和区间参数单调性优化反分析法都能得到令人满意的参数区间。

Because of the universal existence of parameter perturbation and the fault ineluctability for actuator and sensor, it is more important and practical to study robust fault-tolerant control of parameter perturbation for linear system with time-delay.

由于参数扰动的广泛存在性以及执行器和传感器发生故障的不可避免性，使得研究具有参数不确定的时滞系统的鲁棒容错控制问题具有更重要的现实意义。

Moreover, the choices of the singular perturbation parameter are studied, and a new simple and convenient method to estimate the bound of the singular perturbation parameter is designed.

此外，本文还研究了奇异摄动小参数的选取，提出了一种新的简单易行判定稳定性界的方法。

Moreover,in this dissertation,a method ispresented to control safe basin with the fractal erosion,that is by the application ofthe weak parameter periodic perturbation with an optimal frequency to control thefractal erosion basin,and the analytical study shows that the essence of the methodis that the parameter periodic perturbation can be used to delay the occurrence ofhomoclinic tangencies.

并且在本文提出了一种对分形侵蚀安全域进行控制的方法，那就是应用具有最优频率的参数周期扰动对于已受到分形侵蚀的安全域加以控制，在理论分析中得到这种控制分形侵蚀安全域的方法实质上延缓了鞍点同宿相切的发生，同时考虑了外加噪声对控制后安全域的影响，得到这种控制方法具有很好的鲁棒性。

In this paper,a systematic direct perturbation method of dark solitons is found.Having analyzed the mistakes in earlier works on perturbation method for dark solitonsand essence of the direct perturbation method for bright solitons,we notice that to in-troduce the adjoint solutions of the squared Jost solutions and to prove the completenessare crucial to the problem.Giving up the unnecessary scheme of introducing the adjointoperator in the bright soliton case,we directly find the adjoint solutions by meetingthe demand for the orthogonality that inner product of the squared Jost solutions andits adjoint should be proportional to a δ function in the case of continuous spectra.The corresponding adjoint operator is thus found.Taking into account the reductiontransformation,we find a correct description for the completeness of the squared Jostsolutions and directly verify its validity with explicit expressions of the squared Jostsolutions.

本论文建立了系统的暗孤子直接微扰方法，在对前人关于暗孤子微扰方法的错误以及亮孤子直接微扰方法的本质作了充分的分析后，认识到引入平方Jost解的伴随解和证明完备性是问题的关键，撇开过去亮孤子情况首先引入伴随算子的非必要作法，直接从平方Jost解与其伴随解的内积在连续谱时正比于δ函数这一正交性要求出发，找出了伴随解，同时得出了应有的伴随算子，在考虑到约化变换性后，得到了暗孤子情况的平方Jost解的完备性的正确表述，并在单个暗孤子的情况利用平方Jost解的显式直接验证了它的正确性。

Foods high in this vitamin include oily fish such as salmon, tuna and, and fish liver oils.

维生素D含量高的食物包括诸如大麻哈鱼、金枪鱼和鲭鱼之类的油鱼以及鱼肝油。

We need you to cosign our public letter demanding that press intimidation cease immediately, and that all charges be dropped.

我们需要您cosign我们的公共信，要求记者立即停止恐吓，并要求所有收费下降。