坐标系的

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 PSE in the curve coordinate systems are solved by the numerical techniques developed efficiently in this paper. A normal transform is introduced, and there are enough much grids in the region between the critical layer and the wall, where the variation of the disturbance is the quickest. The finite-difference of governing equations with fourth-order accuracy in the normal direction is utilized in full regions including points close the wall, and is very important for accurately discreting equations.

对于曲线坐标系下的抛物化稳定性方程，文中发展了求解的高效数值方法：引进法向变换，使得在临界层与壁面之间的扰动量变化最快的区域有更多的法向网格点；导出包含边界邻域在内的完全四阶精度的法向有限差分格式，这对方程精确离散至关重要；采用全局法和局部法相结合的方法及其新的迭代公式，大大加速收敛并得到更精确的特征值。

This paper discussed the coordinate transformation method of WGS84 coordinate system to 1954-BeiJing Gauss grid coordinate. Introduced transformation model of WGS84 to Beijing 54 and computing method of transformation parameter. According to different model and computing method, computed and compared with the result combine real data. Think that adopt base-line vector quantity ask four parameters model have higher transformation precision.

本文详细讨论了WGS84大地坐标转换到北京54坐标系下的高斯平面坐标的方法，重点介绍了WGS84和北京54的空间直角坐标的转换模型及转换参数的计算方法，并根据不同的模型和计算方法结合实际数据进行计算和结果的比较，认为采用基线向量求解的四参数模型具有较高的转换精度，分区变换和提高控制点精度也能提高转换的精度。

In this dissertation, two methods were adopted to build dynamics model for vehicle ride comfort analysis: one is eight freedom vehicle ride comfort differential equation model in which lateral movement of driver and vehicle body was considered. Combined with time domain model of random road input, we got the driver and vehicles moving displacement.

本文采用两种方法建立了车辆平顺性分析的动力学模型：8自由度车辆平顺性分析的微分方程模型，考虑了驾驶员和车体的侧倾，结合随机路面激励的时域模型，在B级路面输入条件下，进行了时域仿真求解，得到车辆和驾驶员在汽车坐标系中各个方位上随时间历程的运动位移；利用ADAMS软件建立的福田小卡汽车，共计596个自由度的三维实体整车虚拟汽车模型，全面地考虑了影响平顺性的各种因素，然后通过对路面功率谱的变换生成适合于ADAMS／Tire的路面文件，实现了整车虚拟样机在随机输入激励下，车辆振动模型的时域仿真求解。

In this dissertation, two methods were adopted to build dynamics model for vehicle ride comfort analysis: one is eight freedom vehicle ride comfort differential equation model in which lateral movement of driver and vehicle body was considered. Combined with time domain model of random road input, we got the driver and vehicle's moving displacement. The other method, we built a Forland truck virtual prototyping using ADAMS, it is a 3D machine model, totally with 596 freedom degrees, every factor that influences the vehicle ride comfort was considered, finally complete the time domain simulation on random road input.

本文采用两种方法建立了车辆平顺性分析的动力学模型：8自由度车辆平顺性分析的微分方程模型，考虑了驾驶员和车体的侧倾，结合随机路面激励的时域模型，在B级路面输入条件下，进行了时域仿真求解，得到车辆和驾驶员在汽车坐标系中各个方位上随时间历程的运动位移；利用ADAMS软件建立的福田小卡汽车，共计596个自由度的三维实体整车虚拟汽车模型，全面地考虑了影响平顺性的各种因素，然后通过对路面功率谱的变换生成适合于ADAMS/Tire的路面文件，实现了整车虚拟样机在随机输入激励下，车辆振动模型的时域仿真求解。

This project studies the scale-dependent deformation behavior of the metal matrix composite, the void nucleation and void growth mechanisms at the micron/submicron scale. The main results are:(1) In prophase, growth and coalescence of the void embedded in the graded matrix are analyzed in detailed;(2) Based on the infinite solid model containing a micro-void, coupling effects of the void shape and the void size on the void growth are studied carefully, the results show that it seems to exist a critical equivalent void radius, which is associated with the material length. When radius of a microvoid is close to or smaller than the critical void radius, the micro-void growth rate is essentially eliminated;(3) The coupling effects of the particle shape and size on the mesoscopic stress fields within the particle and matrix are also investigated by introducing the conception of inclusion/matrix interfacial energy. The results show that the stress concentration factors within the particle and on the matrix/particle interface are also strongly size-dependent,so the void nucleation mechanism is size-dependent.(4) By employing a specific orthogonal curve coordinate frame and a 'kernel function' conception, a 'unified method'solving the spheriodal and spherical void problems is suggested; by this unified method, size-dependent plastic potentials of the porous materials containing the spheriodal or spherical voids are obtained, which extend the traditional Gurson model for the spherical void and GLD model for the spheriodal voids to the micron scale.(5) Based on the RVE model containing the spheriodal or spherical particles, the influences of the particle shape and size on the size-dependent mechanical behavior of metal matrix composite are studied.

中文摘要：本项目对金属基复合材料在微细观尺度下的尺度相关变形行为、孔洞形核及长大的机理和模型进行了研究，取得了如下主要结果：1）在前期研究中，探讨了基体的梯度分布对孔洞长大和聚合的影响；2）基于含孔洞的无限大体模型，探讨了孔洞形状和孔洞尺寸对其长大的耦合作用，结果表明：可能存在一个与材料特征长度相关的临界孔洞尺寸，当椭球孔洞的等效半径小于临界孔洞半径时，孔洞的长大受到明显抑制；3）通过引入基体/夹杂界面能的概念，分析了夹杂尺寸、夹杂形状对材料细观应力场的耦合影响，结果表明：颗粒内部和界面上的应力集中因子强烈地依赖于夹杂的尺寸和形状，因此，孔洞的形核机理是尺寸相关的；4）采用一种特殊的正交曲线坐标系和引入"核函数"的概念，"统一"地得到了含椭球和球形孔洞的材料的尺寸相关塑性势，它将传统的Gurson球形孔洞模型和GLD椭球孔洞模型推广到微尺度范围；5）基于含椭球和球形夹杂的体胞模型，初步研究了夹杂形状、夹杂尺寸对金属基复合材料尺寸相关力学行为的影响。

This paper takes one low-speed-circumgyrate rocket with a empennage asa research object, set up a relevant reference frame, analyse the strength andmoment on the amended rocket, ratiocinate the sports equation with 6 DOF; analyse the factors which cause terminal windage between pratical trajectoryand fiducial trajectory, take certain rocket for example, make use of theemluator on the influence of estimating precision caused by measuredinformation, find the speed, the trajectory obliquity, the trajectory setoverand the coordinate are the sensitive factor arosing terminal windage of thetrajectory; introduce the developing status of detecting technique, and basedon the actuality, choose the radar in the ground as measure equipment; simplydesign and analyse the setting and inflame control of the impulse engine onthe amended rocket; design the amend method and validate its feasibility takingthe use of emluator.

本文以某型低速旋转尾翼火箭弹为研究对象，建立了相应的坐标系，详细的分析了作用在弹道修正弹上的力和力矩，由动量定理和动量矩定理推导出了在一般形式下的弹道修正弹的空间六自由度的运动方程；对引起弹道落点偏差的因素进行了分析，以某口径火箭弹为例仿真了可测信息量对估算精度的影响，发现速度大小、弹道倾角、弹道偏角和位置坐标是引起落点偏差的主要因素；对弹道探测技术发展现状作综合性阐述，并基于现状，选用地面火控雷达作为测量装置；对弹道修正弹上脉冲推力器的安装和点火控制方法进行了简要的设计与分析；设计了弹道修正弹指令修正的修正方法，通过数字仿真验证了方法的可行性。

On the basement of conventional direct fan-beam reconstruction, this paper gives a newly improved algorithm-"fast filtering-backprojection". This method utilizes the symmetrical circle geometry to sample projection data, and reconstructs image on the Polarcoordinate firstly, then translates this reconstructed image onto the cartesian coordinate system with two interpolating operations so that the computer can show the result image on the VGA screen. This algorithm rebates the calculating backprojection greatly, and shortens a few times of reconstructing time than same kinds of means. With the size of image enlarging, the reconstructing time abates with 2 exponent times. In addition, according to the idea of parallel-beam, we rearrange the fan-beams and reconstruct image using parallel-beam method fastly. The rearranging constraint condition is given here.

本文首先在传统的扇束直接重建方法的基础上，提出了一个改进的快速滤波反投影重建算法，它利用旋转采集投影数据的圆周对称的几何关系，先在极坐标系统内进行图象的重建，然后通过两次内插运算再将图象转换到计算机显示方式下的笛卡尔坐标系中去，该方法将以往的直接重建方法中的反投影时所需的运算大大降低，并将重建时间比同类方法缩短了几倍，而且随着重建图象的尺寸的增大，重建时间以2的指数次方倍相对缩短，并获得了较好质量的重建图象；另外，又根据平行束投影重建图象的思想，对扇形射束进行了重排，然后利用平行束重建图象的方法进行扇束的重建，并推导了&扇束重排重建图象&方法的约束条件。

The article presents the developing condition of PWM and SVPWM first.Then the theory of SVPWM is discussed in detail.The SVPWM is based on the thought of magnetic chain tracking.It makes the ideal magnetic chain circle of three-phased sysmmetry electric motor supplied by three-phased sysmmetry sine wave voltage for basis,uses the practical magnetic chain vector formed by the different switch modes of three-phased inverter to track the basic magnetic chain circle.During the course of tracking,the inverter changes the switch modes properly to form the PWM waves.Then the modulation wave of SVPWM is analyzed in detail.The modulation wave of SVPWM is implicit,but the analogous modulation wave in A-B-C axis needs to be calculated in order to expose the internal relation of SVPWM and SPWM.That is to show the implicit modulation wave of SVPWM. SVPWM actually is a transformed SPWM ruly sampled by the modulation wave which is injected by the zero prefaces based on space vectors.

本文首先对脉宽调制技术的发展现状进行了综述，在此基础上分析了电压空间矢量脉宽调制技术的发展现状；接着对空间电压矢量脉宽调制技术的基本原理进行了详细的分析和推导，SVPWM是基于磁链追踪的思想，它以三相对称正弦波电压供电下三相对称电动机定子理想磁链圆为基准，由三相逆变器不同开关模式下所形成的实际磁链矢量来追踪基准磁链圆的，在追踪的过程中，逆变器的开关模式作适当的切换，从而形成PWM波；然后详细分析了电压空间矢量脉宽调制技术的调制波，虽然SVPWM法的调制波是隐含的，但是为了揭示SVPWM法与SPWM法的内在联系，需要求出SVPWM在A-B-C坐标系上的等效调制波，也就是将SVPWM的隐含调制波显化；SVPWM实质是一种基于空间矢量在三相正弦波中注入了零序分量的调制波进行规则采样的一种变形SPWM。

In the experiment of measuring the basic electric charge by using Millikan method,the selection of oil drop should satisfy the principles of which fall time is within 20 minutes and charged amounts of oil drop are less than five.

在密立根法测量基本电荷电量的实验中，油滴选取应满足下降时间在20秒左右，油滴的带电荷数要少于5个的原则，本文在理论上分析了油滴选取原则的依据，给出了在油滴的下落时间和平衡电压的坐标系中等电荷数的多重曲线，为选择合适的油滴提供了理论上的判断依据。

Neither the killing of Mr Zarqawi nor any breakthrough on the political front will stop the insurgency and the fratricidal murders in their tracks.

在对危险的南部地区访问时，他斥责什叶派民兵领导人对中央集权的挑衅行为。

In fact,I've got him on the satellite mobile right now.

实际上 我们已接通卫星可视电话了