在传播中

As the foundation of ultrasonic testing of composite materials, this thesis is intended to explore in detail a number of features of wave propagation in anisotropic plates, and the following essential problems will be considered:(1) Propagation of plane bulk waves in homogeneous and orthotropic anisotropic media;(2) Lamb wave propagation in multilayered anisotropic plates;(3) Influence of isotropic solid or liquid loading on Lamb wave propagation in anisotropic solid media;(4) Influence of interface layers on Lamb wave propagation in layered anisotropic composite laminates;(5) Dispersion characteristic analysis of attenuation Lamb wave while existing an thin viscous layer which is used for simulating the poor curing in adhesively bonded joints.

作为复合材料超声检测的基础，本文研究了如下国际前沿性的课题：（1）平面体波在正交均匀各向异性媒质中的传播；（2）多层各向异性媒质中Lamb波的传播；（3）各向同性固体或液体负载对各向异性固体媒质中Lamb波传播的影响；（4）界面层对层状各向异性复合媒质中Lamb波传播的影响；（5）胶粘剂未固化而呈现粘弹性时粘接结构中衰减Lamb波的频散特性分析。

The transverse wave disturbance along tangential base flow of circular vortex is discussed By using numerical method we study this instability of baroclinic flow which is mesoscale inertia wave instability on the cylindrical coordinate The influence of stratification stability N 2 , Coriolis parameter f 0 , the vertical shear of tangential wind z of the ambinent atmosphere and the latent heat on the growth rate of instability is studied From the above analysis and calculation, we can learn that there are Eady mode and mesoscale mode of transverse wave instability in circular vortex as well Furthermore we also learn that distribution character of mesoscale mode disturbance field of transverse wave instability, anomalistic "cats eye" structure of lower level and the character of the slowly spreading disturbance converges at low level and the quickly spreading disturbance converges at high level

作者中文名：李红金；陆汉城；宋晓亮；李鲲摘要：讨论涡旋大气中，存在沿切向基流传播的横波型扰动，并采用数值方法讨论了柱坐标系下圆形涡旋系统斜压气流中这类扰动的不稳定，这是一类中尺度的重力惯性波的不稳定。研究了涡旋环境大气的层结稳定度参数N2、切向风垂直切变Vz、凝结潜热、涡旋特性及科里奥利参数f0对不稳定增长率的影响。圆形涡旋中同样存在横波不稳定的Eady模态和中尺度模态，得到了中尺度模态的扰动场分布特征：流场的不规则"猫眼"结构及慢速传播的扰动均集中在低层，而快速传播的扰动均集中在高层的扰动特征。

The results show that when gravity wave's propagating in the homogenous winds, the nonlinearity is stronger in the fair wind than in the contrary wind, the background winds change the propagation velocity and path, and when gravity wave's propagating in the homogenous winds, the vertical wavelength decreases, the average upgoing energy flux reduces which implies the ambient winds absorb the energy of the wave, realizes coupling of the different atmosphere layers.

结果表明，当重力波在均匀风场中传播时，非线性效应在顺风场中比在逆风场中更显著，背景风会改变重力波在水平方向的传播速度和传播路径；当重力波在剪切风场中传播时，重力波在垂直方向上平均能流随高度的增高而减少，表明背景吸收了重力波的能量，在重力波向上传播的过程中，实现了大气各层之间的耦合。

Using the modern medium theory, the present study has analyzed the status of application of internet to the sports information dissemination.

运用现代传媒理论，分析了互联网在体育信息传播中的应用现状。

In traveling through the sea, an underwater sound signal is affected by many factors and takes much information of the ocean.

水声信号在海洋中传播时受到各种海洋环境因素的影响，携带了大量的海洋环境信息。

The study on Rayleigh wave characteristics in layered soil shows that shear wave velocity of soil can be attained.

许多学者对瑞利波在地基中的传播特性的研究表明，瑞利波能够反演地基土的剪切波速度，而剪切波速度跟地基土特性又有联系，因此，可以利用瑞利波法来反演地基土的特性。

When traveling through a medium higher frequency waves travel ever so slightly faster than lower frequency ones.

在介质中传播的时候，高频率的电磁波会比低频率的稍微快一点，哪怕只是一点点。

In gases, consists of a sequence of compressions and rarefactions that travel through the gas.

在气体中传播时，声波由一个浓缩和稀薄序列组成。

Base on the analysis, the interface between a nonlinear lefthanded material and a righthanded material can support both forward TE surface waves and backward TE surface waves under certain conditions.

针对电磁波在非线性左手系材料中的传播性质，分别研究了左、右手系材料界面以及两左手系材料界面上非线性TE表面波的传播行为讨论了导波的频率特性、色散关系以及群速度随频率的变化规律分析表明，两种界面上的非线性TE表面波均存在频率通带和禁带，且带宽是传播功率的函数揭示了在一定条件下，左、右手系材料界面上既可以支持正向传播的非线性TE表面波，也可以支持反向传播的非线性TE表面波；两左手系材料界面上表面波的传播性质因材料参量的变化差异较大，一定参量条件下，该界面上仅支持反向传播的非线性TE表面波。

In this thesis,firstly the calculated results of Helmholtz's equation in the magnetic field of dielectric slice is discussed.

1引言利用矩阵方法描述光在介质中的传播是一种行之有效的方法，其结果物理意义明确。M。

According to the clear water experiment, aeration performance of the new equipment is good with high total oxygen transfer coefficient and oxygen utilization ratio.

曝气设备的动力效率在叶轮转速为120rpm～150rpm时取得最大值，此时氧利用率和充氧能力也具有较高值。

The environmental stability of that world - including its crushing pressures and icy darkness - means that some of its most famous inhabitants have survived for eons as evolutionary throwbacks, their bodies undergoing little change.

稳定的海底环境─包括能把人压扁的压力和冰冷的黑暗─意谓海底某些最知名的栖居生物已以演化返祖的样态活了万世，形体几无变化。