切变波

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。

An inhomogeneous Benjamin-Davis-Ono-Burgers equation including topographic forcing and turbulent dissipation is derived in terms of the quasi-geostrophic vorticity equation, an approximate analytic solution of the BDO-Burgers equation with a small dissipation is obtained, the time variations of mass and energy of the algebraic solitary waves are discussed, and finally, the forced BDO-Burgers equation is integrated numerically and the numerical solutions are given for a given basic flow with a weak shear and a localized topographic forcing.

利用包括地形外源和湍流耗散的准地转涡度方程导出了包含强迫项和湍流耗散项的非齐次强迫BDO-Burgers方程，求出了小耗散存在情况下BDO-Burgers方程的近似解析解，讨论了代数孤立波的质量和能量的守恒关系，最后，对给定的弱切变基本气流和局地地形强迫，数值积分强迫BDO-Burgers方程，求得了不同参数下的数值解。

As a way of ocean engergy transport, internal waves propagation leads to onflow and sea water mixing and has an effect on the local water exchange, sediment and resuspending.

内波在密度跃层附近生成并传播，伴随着等密度面较大的起伏和较强的流速切变，威胁着水下潜艇的航行安全，对海上石油平台的作业也有较大影响。

According to piezoelectric equation and vibration theory of quartz crystal, we studied the elastic wave＇s transmission characteristic in a AT-cut thickness-shear-vibration quartz crystal, and the frequency conditions of which quartz crystal resonator formed stationary wave in electrode district.

根据石英晶体的压电方程和晶体振动理论，研究了AT-切石英晶体厚度切变振动模式下振动频率与结构参数间的关系，以及石英晶体谐振器在电极区形成稳衡驻波的频率条件及电极区外波的传播特性。

Study is performed of the stability of Kelvin wave and zonal symmetric disturbances in zonal shear flow.

分析了纬向切变基流中的赤道Kelvin波以及纬向对称扰动的稳定性。

Horizontal windspeed shear,if bigger than a critical value associated with vertical wavenumber m, factor β, hydrostatic stability N^2 and Richardson number Ri ,leads to instability of equatorial ifiternal inertial gravity wave on the y-z plane,which thus causes zonally syrmnetric disturbances to emergence and development.

只要风的水平切变足够大，大于某一临界值（该临界值与垂直波数m，β因子，静力稳定度N^2以及Richardson数Ri有关），在赤道y-z平面上的重力惯性内波也会发生不稳定，从而引起这种沿x轴对称扰动的激发产生与发展。

Results show that using bin to bin automatic gain control,clutter filtering,and suitable antenna tilt management,the " wet " microburst windshear can be accurately detected 80s(approximately 6km) in front of the aircraft,meeting the certification requirements proposed by FAA.

结果表明：通过单元－单元自动增益控制、杂波滤波和天线仰角控制，可提前80s（6km）探测到&湿&微下击暴流风切变，符合FAA提出的适航要求

With Death guitarist Schuldiner adopting vocal duties, the band made a major impact on the scene.

随着死亡的吉他手Schuldiner接受主唱的职务，乐队在现实中树立了重要的影响。

But he could still end up breakfasting on Swiss-government issue muesli because all six are accused of nicking around 45 million pounds they should have paid to FIFA.

不过他最后仍有可能沦为瑞士政府&议事餐桌&上的一道早餐，因为这所有六个人都被指控把本应支付给国际足联的大约4500万英镑骗了个精光。