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The interaction and the perturbation between a metal-coated fiber probe and an aperture evanescent field is analyzed numerically using finite-difference time-domain method.

采用时域有限差分方法对镀金属膜光纤探针在近场光探测中对光场产生的扰动和相互作用过程进行了数值分析。

Based on mass-spring model, a method of automatic mode-selecting method is presented to solve the difficulties of selecting corresponding modes close to the excitation frequency, in adaptive perturbation for mistuned bladed disks.

摘要针对自适应摄动法在失谐叶盘受迫振动分析中，选择接近激振力频率的相应模态数目难于控制的问题，基于质量－弹簧模型，提出一种自动选择模态的方法。

This parameter canaccurately describe the degree of concentration of vibratory energy of the systemmodal shape in quantity. Using this parameter, the effects of mistuning on thelocalization of system modal shapes for various orders are studied. The reasons of themodal localization phenomenon are analyzed by the perturbation method.

利用所提出的模态局部化参数，研究了失谐对叶盘系统各阶模态局部化程度的影响规律，并利用摄动法对失谐所导致的模态局部化现象进行了分析；同时还发现，失谐叶盘系统的某些中间阶模态的局部化参数值在弱耦合区域的特定位置会产生奇异的突变现象，而这种突变现象是用摄动法难以解释的，并且可能会对失谐叶盘系统的振动稳定性产生重要影响。

In Chapter 2, the introduction of the dynamical models is presented, furthermore, on the basis of analyzing perturbation factors there are two dynamical models fit for the motion situation of the NEAs, which are imported as the restricted authentic particle model and the restricted mean particle model (with respect to the treatment of the orbits of the perturbing major planets) that the Post-Newtonian effect is also taken into account, while for the latter the influence of the 5/2 (or 2/5) resonant items of the interaction between the Jupiter and the Saturn is considered.

第二章是关于力学模型的介绍，在分析摄动因素的基础上，引入了近地小行星运动中比较合适两种力学模型，即限制性质点真实模型与限制性质点平均模型(这一平均指的是对摄动源大行星轨道的处理)，在两种模型中均考虑了后牛顿效应，另外在平均模型中还考虑了木星与土星之间的5/2(2/5)共振项的影响。

Evidence suggests that 1 under more stable stratification, the basic flow, if moving faster at low and high levels (particularly in the presence of jets there), allows a resulting meso-β unsteady wave to propagate eastward with respect to basic flow and even at greater velocity compared with it; 2 vertical windspeed shear of basic flow causes instabilities of the TWT perturbation; 3 considering the second derivative of basic-flow wind with respect to z (denoted by zz≠ 0 which is simply given as β* hereafter) the expression for the phase velocity of vortex Rossby wave is obtained, which is unidirectional in propagation with respect to basic flow; 4 VRoW has its physical origin from β*, i.e., from z-varying heterogeneities of y-direction averaged vorticity of the basic flow field; 5 VRoW phase velocity is associated with zonal wave number k, its energy is dispersive and the group velocity exists in the x direction; 6 when windspeed meets the condition of β*, TWT disturbance instability may be that of mixed VRoW and gravity wave; 7 if basic flow is subject to linear shear but does not meet the condition of β*, the TWT instability is that of inertia-gravity wave.

在大气层结比较稳定的情况下，如果基本气流在低层和高层较大(有可能存在低空急流和高空急流)，此时产生的β中尺度不稳定扰动相对于基流向东传播，甚至于快速向东传播。基本气流在垂直方向上的风速切变对于中尺度横波型的扰动起着不稳定的作用。如果考虑基流的二次切变，可以得到涡旋Rossby波的相速度表达式，涡旋Rossby波相对于基本气流是单向传播的。涡旋Rossby波产生的物理根源是基本流场的风速二次切变，亦即基本流场y方向的平均涡度在空间z方向上的不均匀所致。涡旋Rossby波的相速度与纬向波数也有关，它的能量是频散的，其在纬向x方向也存在群速度。在基本流场的风速存在二次切变时，横波型不稳定可能是混合的涡旋Rossby重力波的不稳定；而在基本流场的风速仅仅存在线性切变，不存在二次切变时，横波型扰动的不稳定则是重力惯性波的不稳定。

In this paper, a reconstruction algorithm of acoustical tomography is presented for absorbing scatterers based on the second-order Rytov transform perturbation approximation.

文中详细讨论了Rytov二阶近似下的声逆散射微扰论公式，并考察了它的适用范围。

In the meanwhile, the TS characteristics of a scattering particle and their relationship are studied when it is passing through the scattering area, In addition to this, the distribution function of particles' shape is defenited in terms of math's method and a new method is putout of which the distribution of particles' shape is captured in according to the power spectrum and spectral distribution characterist of light scattering and finally, the utility of the perturbation ameliorating method and the effect of the particles' shape is modified, so far, the accuracy of measurement of the particles' size is improved effectively.

对此，本文在以Mie散射理论为原理，依据前向接收器接收的前向散射光信息以获取微粒大小信息的测量基础上，对微粒穿越光敏区时的时域与空域的特征以及相关性开展了研究，从数学上定义了微粒的形体分布函数，提出了一种依据光散射功率潜和频谱分布特征来获取微粒形体分布信息的方法，完善了微扰修正理论的应用性，有效地改善了形体的影响问题，从而可提高微粒粒度分布测量结果的准确性。

Regarding a viscous normal shock wave in a high-pressure metal as a continuous profile, this paper points out that any little perturbation shock is stable under any Reynolds number, and material viscosity is a stabilized factor.

本文中针对平面正激波，认为高压金属中的粘性激波的物理量是连续变化的，利用线性稳定性理论，用数值解推论出：在有粘性条件下小扰动激波都是稳定的，物质粘性是致稳的因素。

The excluded volume effect of nucleons is studied by calculating the first order self-energy of the nucleon in nuclear matter with perturbation theory as the volume of nucleons is considered, then its influence on the equation of state of nuclear matter is discussed.

在相对论平均场框架内计算了核子体积对核物质中核子自能的一级微扰修正，并进一步讨论了这种修正对核物质状态方程的影响。

We addressed the solutions of the collision-less plasma Vlasov-Poisson system, involving Vlasov equation coupled with Poison equation, in quasi-neutral limit. The two asymptotic-preserving particle-in-cell methods were developed and applied to a model of one-dimensional, periodic perturbation plasma.

针对准中性无碰撞等离子体的Vlasov方程及与其相耦合的求解电势的Poisson方程所组成的Vlasov-Poisson系统，提出了两种渐近保持PIC算法，并将其运用到一维周期性波动等离子体模型上。

And Pharaoh spoke to Joseph, saying, Your father and your brothers have come to you.

47：5 法老对约瑟说，你父亲和你弟兄们到你这里来了。

Additionally, the approximate flattening of surface strip using lines linking midpoints on perpendicular lines between geodesic curves and the unconditional extreme value method are discussed.

提出了用测地线方程、曲面上两点间短程线来计算膜结构曲面测地线的方法，同时，采用测地线间垂线的中点连线和用无约束极值法进行空间条状曲面近似展开的分析。