相对孔径

Polarimetric Synthetic Aperture Radar measures the frequency, magnitude, absolute and relative phase of targets' backscattering signals in imaging scene for any possible combination of transmit and receive antennas. The polarization synthesis technique on one hand has greatly increased the acquired polarization information, on the other hand increased the difficulty of system design and signal processing.

中文摘要极化合成孔径雷达的回波信号可以提供不同收发极化状态组合下成像场景内目标散射波的幅度、绝对和相对相位、频率等信息，极化合成技术的出现使获取的信息量成倍增加，信息量增加的同时系统设计和信号处理的复杂度增加，因此极化合成孔径雷达相关技术的研究成为微波遥感领域的热点。

A real-time interferometric method for testing asphere was proposed to measure aspherical surface with small asphericity without other null optics.

对非球面度较小的非球面，直接利用标准球面镜作为参考表面，通过数字干涉仪可以测得全孔径位相分布，将所得的数据剔除参考球面波相对理论非球面的偏差，并运用最小二乘拟合求得机构定位误差，消去此误差，即可获得真实的面形信息。

Design sug gestion about holes iameter and comparative anchorage length were proposed.

并对植筋时的钻孔孔径和相对锚固长度提出了设计建议。

The result indicates that the output power oscillates and weakens along with increasing input power,and its oscillation period depends on the distance between the medium and beam focal point.Limiter′s limiting ability will decrease if waist size of the incident Gaussian beam and the aperture size increase.With a fixed input power scope,medium′s best limiting position will move towards the focal point if waist size of Gaussian beam and the aperture size increase,but the best limiting position will change a lot with different input power scopes.

结果表明：限幅器的出射功率随入射功率的增加衰减振荡，其振荡周期取决于介质相对于光束焦点的位置；限幅器的限幅能力随入射光束腰半径和光阑孔径的变大而减弱；入射功率范围固定，入射光束腰半径和光阑孔径增大时，介质的最佳限幅位置向入射光束的焦点靠近，但是在某些入射功率范围内会存在多个最佳限幅位置；光限幅器的箝位输出功率随光阑线性透过率的增加存在线性增加和非线性增加两个不同区域，实际应用中应在线性增加区域确定光阑孔径的大小。

It is found that, compared with the vacuum sintering, the magnet sintering at argon protection has lower density, magnetic-energy product and remanence, but coerciveforces are higher. The magnet has more and bigger pores, and there obviously exist loose microstructure, the Nd-rich phases are clearly distributed along the grain boundaries mainly in the shape of lumpish and lamelliform.

研究发现，与真空烧结相比，采用Ar保护烧结时磁体的密度、磁能积和剩磁相对较低，矫顽力较高，磁体中形成的孔洞较多，孔径较大，并有明显的显微缩松存在，富Nd相的数量明显较多，且主要呈块状和片状沿晶界分布。

The rebuts indicate that the magnitude of matric suction in soils is controlled by aperture size, and it is interrelated with equilibrium retative humidity of the circumstances,...

研究表明，基质吸力的大小受土的孔径大小的影响；在环境条件下，基质吸力的大小受外界平衡相对深度的影响；土的孔径分布决定了土水特征曲线的特征。

Further,it puts forward a new method,which is based on the lens' assemble plane and realizes the purpose of optical system imaging clearly by refacing revolution mechanic part two times and adjusting imaging distance.

简单的家用相机，摄相机等含有光学系统的成像仪器，它们所包含的镜头焦距短，相对孔径大，成像像面小，成像质量要求较低，通过机械和光学的加工可以保证，只

The modulation of cross section is obviously,the intensity of it is smaller as the circular aperture is bigger and the intensity is bigger as the circular aperture is smaller.

平顶高斯光束经过圆孔衍射，孔径大时光强在横截面调制越厉害，但是强度小；孔径小时光强在横截面调制相对小，但是光强度相对大。

When the receiving aperture is much larger than the scattering disk scale, the aperture-smooth effect is remarkable and the derived variance approximates the result given by weak-fluctuation theory for any zenith; when the receiving aperture is much smaller than the scattering disk scale, the low-pass filter effect of the scattering disk scale is dominating and weak-fluctuation theory is valid only for small zeniths.

散射盘尺度和接收孔径对到达角起伏起平滑作用，当接收孔径远大于散射盘尺度时，由于孔径平滑作用，导出的表达式在任意天顶角都可以近似为弱起伏理论给出的结果；当接收孔径小于散射盘尺度时，散射盘尺度的平滑作用明显，接收孔径的平滑作用相对较小，传统的到达角起伏理论仅在小天顶角是适用的，在大天顶角必须用新导出的方差表达式。

The design principle of the laser receiver with wide FOV for the laser command guidance and laser-beam riding guidance is introduced. A mathematic model of receiving light field is presented. The formula for the viewing angle of the detecting optical system was derived according to the diffraction light field of the oblique incidence parallel light. Taking a detecting optical system with the collecting objective for example, the design characteristic that the receiving optical system needs not only an extra large relative aperture but also an unvignetting receiving performance is discussed on the premise of meeting the requirement of 1064nm WFOV laser receiver.

介绍激光指令制导和激光驾束制导的大视场激光接收机的设计原理，给出接收光场的数学模型，由斜入射平行光的衍射光场推出探测光学系统的视场角公式，根据1064nm大视场激光接收机技术要求，以聚光物镜型探测光学系统为例，探讨接收光学系统既须具备特大相对孔径，又须具备无晕接收性能的设计特点，采用窄带干涉滤光镜进行光学滤波降噪。

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