全等变换

This thesis discusstion these contents, optics of lens characteristic, Fourier transform lens's performance index,design characteristic, structure type, etc. especially, do a lot work in quadruplet full symmetrical double far distance fourer transform lens aspect.

论文对光学透镜的傅里叶变换特性，傅里叶变换透镜的性能指标、设计特点、结构类型等作了研究，尤其是在四组元全对称双远距傅里叶变换透镜方面做了大量的工作。

Some properties of inversions are proved, It indicates that the inversion is conformal, the image of line of curvature is still the line of curvature of the inversion S of the hypersurface S, the principal curvature, the total curvature, and mean curvature of S are the functions...

在n-1维超曲面的反图变换中，示明反图变换为保角表示法，曲率线系的反影仍为反超曲面的曲率线系，反超曲面的主曲率，全曲率与平均曲率为原超曲面的主曲率的函数等。 3。最后导出公式(1)在四维空间与通常空间之特殊形式

The high resolution image of full hole can be obtained from the being processed imaging logging information, and the morphological features about intersecting lines of fracture face and borehole present monocyclic sine curve.

成像测井数据经处理后可得到全井壁高分辨率的图像，而裂缝面与井筒的交线在图像上的形态特征呈现为单周期的正弦曲线，应用哈夫变换的点－线对偶性拾取图像中的裂缝角度等信息，可得到较好的处理结果。

The theoretical analysis and simulation results of 1kW 40~60VDC/380VDC full-bridge Boost mode two-input DC-DC converter have shown that the converter has the advantages such as double isolation among multiple input sources and between output and input of the converter, simple topology, strong voltage matching ability, multiple input sources can supply the power simultaneously or individually, small input current ripple, high power density, high conversion efficiency, high reliability at short circuit, magnetic flux of high-frequency transformer easy to add up etc.

1kW 40～60VDC/380VDC全桥Boost型双输入直流变换器的理论分析和仿真结果表明，这种变换器具有多路输入源之间以及输出与输入源之间双隔离、电路拓扑简洁、电压匹配能力强、多路输入源可同时或分时供电、输入电流纹波小、功率密度高、变换效率高、负载短路时可靠性高、高频变压器磁通易于叠加等优点。

If without dissipation, the propagation is essentially a symplectic transformation with one parameter, and, consequently, the numerical calculation methods of the propagation ought to be symplectic, too.

至今 ，已发展起来了许多方法，如计算走时的射线追踪法，计算全波场的有限差分法和有限元法等[1— 5 ]，以及随后发展起来的其他方法，如傅立叶变换法[6 ]、小波变换法[7，8]和各种结合算法[9，10 ]等。

Its final target is to fully digitize the analogue receiver. The all digital receiver not just means digitizing every unit of the analogue receiver, but is a new receiver architecture. The two outstanding characters of this new architecture is: 1 It uses a high stable oscillator to generate a fixed frequency source. And both the sample signal and the local carrier required are obtained from it. 2 Once the received signal has been sampled by a high speed A/D converter, some digital signal processing algorithms will be used to realize all further processes, such as digital down-converting, match filtering, symbol timing, channel equalizing, carrier synchronizing, demodulating and decoding.

全数字接收机并不是简单地将传统的模拟接收机中所有的部件数字化的结果，而是一种全新的接收机体系结构，这种新的体系结构具有两个最为突出的特点：1）采用高稳定度晶体振荡器产生一个固定的本地频率源，接收机中所需的采样时钟信号和本地载波均从这一固定频率源得到；2）接收信号一旦经过高速模数转换后，余下的工作如频率变换、匹配滤波、定时同步、信道均衡、载波同步、符号解调、判决与译码等全部由数字信号处理算法来实现。

The split between the two groups can hardly be papered over.

这两个团体间的分歧难以掩饰。

This approach not only encourages a greater number of responses, but minimizes the likelihood of stale groupthink.

这种做法不仅鼓励了更多的反应，而且减少跟风的可能性。