查询词典 polarization wave

In this chapter, three kinds of target recognition methods are performed, which are:①Target recognition method based on the description of polarization parameter plane. The echo polarization states of target are projected onto the polarization state plane described by the ellipticity ε and the tilt angle τ of the polarization ellipse, the change of parameter following ferquency becomes the chart. According to the changing trait of the chart, the multidimensional polarization feature space of target has been contructed. Furthermore, a series of polarization feature parameters used in designing the structure of target recognition device are extracted, and they are insensible to the posture of target.②Target recognition method based on the description of Poincare polarization sphere. The echo polarization states of target expressed by Stokes vector are projected onto the Poincare polarization sphere. The conception of polarization ferquency stability, which is used in describing the dynamic distribution characteristics of the target echo polarization states on Poincare polarization sphere, has been defined. A group of polarization feature parameters used in designing the structure of target recognition device are extracted, and they are insensible to the posture of target.③Target recognition method based on the description of frequency sensitivity. In accordance with the conception of the polarization state distance defined on Poincare polarization sphere, the frequency sensibility of the physical structure property of target has been investigated, the frequency distribution feature curves in PSD domain are obtained, and targets'features are extracted by means of the curve-fitting method with Least Square Criterion.

这章具体研究了基于三种极化散射特性描述的相应的目标识别方法：①基于极化参数平面描述的目标识别方法，将目标回波极化状态投影到以极化椭圆参数，即椭圆率角ε和倾角τ表征的极化状态平面上，参数随观测频率的变化就形成了图，根据图的变化特点构造了目标的多维极化特征空间，并提取了不敏感目标姿态变化的极化特征参数组来设计目标的识别器结构；②基于Poincare极化球面描述的目标识别方法，采用Stokes矢量表征目标回波的极化状态，并将其投影到描述极化状态的Poincare极化球面上，定义了极化频率稳定度的概念用以刻画目标回波极化状态在Poincare极化球面上的动态分布信息，提取了准方位不变性的目标极化特征，最后设计了目标的识别器结构；③基于频率敏感性描述的目标识别方法，通过在Poincare极化球面上所定义的极化状态距离的概念，研究的是复杂目标物理结构特性对探测信号频率的敏感程度问题，获得了在极化状态距离下的频率分布特性曲线，采用最小二乘估计曲线拟合方法，它既用于极化特征的降维，同时又直接将拟合参数作为目标的分类特征。

The method utilizes an optical device which consists of polarization control elements and polarization beam splitting pieces for realizing the multi-switching of polarization or non-polarization light; in a position sequence, one polarization beam splitting piece is arranged on a main optical path at the back surface of each polarization control element, thereby commonly constituting a 'single-pole double-throw' optical switch with a controller; the controller changes the polarization state of input light beams by driving the polarization control elements according to the control logic, and the input light beams are switched to any one path on an output channel through the polarization beam splitting pieces, thereby completing the designated optical information processing function.

利用偏振控制元件和偏振分束片两种光学元件组成的光学装置实现偏振或非偏振光的多路切换；在位置序列上，每个偏振控制元件后面主光路上放置一块偏振分束片，并和控制器共同构成一个'单刀双掷'光开关；控制器按照控制逻辑驱动偏振控制元件改变输入光束的偏振态，并通过偏振分束片将输入光束切换到输出通道上的任何一路，来完成指定的光信息处理功能。

Angular spectral is spectral value map formed by estimating semblable coefficients of fast and slow shear wave or the variation of amplitude ratio of fast and slow shear wave with times and angles at a specified space point based on semblable theory of fast and slow shear wave, the angle value of this space point at a given time can be got by picking the maximum of angular spectral; the study reveals that fast and slow shear wave with different polarization direction should be separated using different rotation formula, eight formulas of separating fast and slow shear wave using clockwise rotation and counterclockwise rotation have been derived, and gained energy assignment rule and phase coincidence rule, in real data estimation, the rotation formula used for separating fast and slow shear wave can be uniquely determined on the two discriminating rules. On the basis of semblable theory of fast and slow shear wave, the delay time corresponding to the maximum of semblable coefficients at a specified point in a given time window is the delay time of fast and slow shear wave, delay time section of fast and slow shear wave can be got by moving space point and smoothing time window. The vertical variation values of delay time of fast and slow shear wave reflect the effect degree of vertical fractured reservoir on fast and slow shear wave which is defined as anisotropic coefficient, and section map of anisotropic coefficient can be obtained.

角度谱就是利用快慢横波的相似性原理，在某一空间点求出快慢横波的相似系数或快慢横波的振幅比值随着时间和角度的变化而形成的谱值图，拾取其极大值就得到该空间点某一时间的角度值；在研究中发现分离不同偏振方向的快慢横波应该采用不同的旋转公式，推导出了利用顺时针旋转和逆时针旋转分离快慢横波的八个公式，并给出了能量分配准则和相位一致性准则两个判别准则，在实际计算中利用这两个判别准则能唯一地确定分离快慢横波的旋转公式；根据快慢横波的相似性原理，在某一给定点和给定时窗内最大相似系数对应的延迟时间就是快慢横波的延迟时间，随着空间点的移动和时窗的滑动就可以得到快慢横波延迟时间的剖面图；快慢横波延迟时间与慢横波传播时间的比值定义为裂缝密度，并求出了裂缝密度剖面图；快慢横波延迟时间纵向上的变化值的大小反映了纵向上裂隙层对快慢横波影响的大小，定义为各向异性系数，并求出了各向异性系数的剖面图。

The results of 3-D numerical modeling of the transversely isotropic media with horizontal symmetry axis and the orthorhombic symmetry media showed that quasi P wave,quasi-SV wave and quasi-SH wave occurred during elastic wave propagation in 3-D anisotropic media. Meanwhile, the special phenomena such as the S wave splitting, the blind zone of S wave splitting and quasi-SV wave-front triplication were clearly observed. In addition, the elastic wave-fronts are spatially changed, and the coupled relations among the quasi-P wave,quasi-SV wave and quasiSH wave in 3-D anisotropic media are very complex.

对方位各向异性介质模型和正交各向异性介质模型中弹性波的传播进行的三维数值模拟结果表明，弹性波在三维各向异性介质中传播时存在拟P波、拟SV波和拟SH波，并出现横波分裂、横波分裂盲区、波面三分叉等特殊现象，另外，性波场在空间是变化的，其拟P波、拟SV波和拟SH波的耦合关系比较复杂。

Through S-wave polarization scanning mode of ultrasonic impulse testing, rock samples with three different properties are measured to evaluate the variation of S-wave velocity in three perpendicular coordinates. By analyzing S-wave splitting of three directions and polarization of the maximum or minimum speed S-wave amplitudes, we think that the velocity orthotropy and fracture orientation observed in the grain sandstones and crack marble samples can be estimated in terms of the polarization and velocity of S-wave. Also, perpendicularity characteristics on the two types of rocks can attribute to the bedding and structure of rocks (directional grains or crystallize).

在实验室通过选择了三种不同岩性的岩石，采用超声脉冲测试方法中的横波偏振扫描方式，观测了岩石样品三个坐标方向上的横波速度变化，通过分析三个传播方向上出现横波分裂的差异，以及出现最大或最小快慢横波振幅的偏振方向发现，可从横波偏振方向和速度值判断出纹理砂岩和裂隙大理岩样品存在不同程度的速度正交各向异性和裂隙方向等特征，认为这两种岩石的正交特性的原因是岩石的层理或裂隙与岩石本身的结构构成的。

Asian citrus psyllids and in the Citrus Aphis citricola both the phloem feeding insects, but insect feeding behavior of two significant differences, in addition to two kinds of insects share a common EPG wave (A wave, B wave, C wave, E1 wave, E2 wave, G wave), the wave of Aphis citricola appeared in the path of many pd wave, pd wave is aphids in plant cells in the epidermis during exploratory puncture the cell membrane caused by feeding, which kind of contact information on the intracellular selection in the aphid host plant play an important role in the process.

求中文翻英文翻译，很急，谢谢亚洲柑桔木虱和绣线菊蚜在沙田柚上都为韧皮部取食性昆虫，然而，两种昆虫的取食行为有明显差异，除了两种昆虫拥有共同的EPG波形（A波、B波、C波、E1波、E2波、G波）外，绣线菊蚜在路径波中出现很多pd波，pd 波是蚜虫在植物表皮层细胞的试探性取食时刺破细胞膜而产生的，这种对胞内信息的接触在蚜虫选择宿主植物的过程中起了重要作用。

Circular polarization is one of microwave equipment with broad application.its the mostly function is switch linearly - polarized wave into circular polarized wave.grating- circular polarization is one of circular polarization,its advantage is simple structure and ease of processing.it is prone to expand high power and high efficiency range.because circular polarization have expand application..

光栅圆极化器是其中的一种，它具有结构简单，加工实现容易，易于向高频率、高功率应用扩展等优点。

A FDTD program was written and the electromagnetic fields for various polarized incident beams are calculated and the polarization states of the diffractive waves are extracted. The relation between the polarization state of the diffraction wave and the grating balzed angle and polarization angle for the linearly polarized incident wave is analyzed; In the spectral range of 1530 ~ 1570nm, the polarization dispersion is studied for the linearly and circularly polarized incident beam.

用时域有限差分程序计算出任意偏振方向线偏光经过闪耀光栅衍射后的电磁场分布，提取衍射波的S偏振和P偏振分量，分析它们与光栅闪耀角和入射光波偏振角的关系；分析在1530 -1570nm光谱范围内，入射光波为线偏振波和园偏振波时，衍射光波的偏振色散特性与光栅闪耀角的关系。

This article first antenna, microstrip theory, the circular polarization technology, the theoretical discussion, in this based on the microstrip antenna of circular polarization method - corner square microstrip antenna, and has done a design simulation , and then do the design and further research to improve and eventually get a resonant frequency (S11 reflection coefficient corresponding to the minimum frequency) for the 1.5GHz and 1.43GHz, the frequency of circular polarization for the 1.46GHz, S11 is less than -10dB relative bandwidth, the VSWR is less than 2 is about 8.8% relative bandwidth, axial ratio less than 3dB relative bandwidth of about 2.2% of the right circular polarization microstrip antenna design case, which proved very good the circular polarization microstrip antenna theory, also fully confirmed by a square corner design is a practical program, and select the appropriate regulation of sticks is indeed able to improve the performance of the antenna.

本文先对天线、微带理论、圆极化技术等进行了理论论述，在此基础上，提出圆极化微带天线的实现方法——切角方形微带天线，并对此做了设计仿真，后又对这一设计方案做了改进及进一步研究，最终得到一个谐振频率（反射系数S11 的最小值所对应的频率）为1.5GHz和1.43GHz，圆极化频率为1.46GHz，S11 小于-10dB 的相对带宽、驻波比小于2 的相对带宽约为8.8%，轴比小于3dB 的相对带宽约为2.2%的右旋圆极化微带天线的设计案例，从而很好的印证了圆极化微带天线理论，也充分证实了切角方形是一种切实可行的设计方案，而选取合适的调节枝则确能提高天线的性能。

The main research contents and results are given as follows:(1) Principles and characteristics of different types of polarization controllers are analyzed, the compare of the difference of these polarization controllers are discussed based on them, drawn a conclusion that the polarization controller which based on squeezing fiber and has variable delay quantity are suitable for high speed optical communication system.(2) The reset principle of the typical four channel polarization controller which is based on squeezing fiber is analyzed, and the design of its concrete reset scheme is given based on them. The reset process and the corresponding operation list are given in detail.(3) The systematical experiment is made when the typical four channel polarization controller is put into the PMD compensator. The experiment result showed that the channel which needs reset can efficiently return to the mean place, and the effect of reset was good, it didn't cause any badness infection on PMD compensation.(4) A new type optical signal time-domain depolarizer is given, and a new PMD compensate method is given based on it.

由此得出延迟量可变型光纤挤压型偏振控制器适用于高速光通信系统的结论；(2)具体分析了典型的四通道光纤挤压型偏振控制器的复位原理，并在此基础上对其进行了具体复位方案的设计，给出了各种情况下的详细复位流程和相应的复位操作列表；(3)将四通道光纤挤压型偏振控制器应用于偏振模色散补偿器中进行系统实验，实验结果表明，需要复位的通道能有效地回到中间值，复位效果良好，且复位未对PMD补偿产生不良影响；(4)设计了一种新型的光信号时域退偏器，并基于该退偏器提出了一种新型的偏振模色散补偿方法。

In contrast to the ubiquitous rising-sun-with-rays military flag of the Japanese, Chinese banners and ensigns feature a range of designs.

与遍地都是的太阳军旗不同，中国人的旗帜和徽章设计得各式各样。

From their small corner of Feng's Guangzhou headquarters -- a jumble of pink leashes, squeezable rubber steaks, and plastic doggy Santas for Fido's stocking -- Soleil's designers come up with at least five new products a month.

从Feng 设在广州总部的产品展示柜台上可以看到，Soleil的设计师每月至少设计出5件新产品。