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The proposed beamformer represents a modification of the popular minimum variance distortionless response beamformer. It minimizes the array output power while maintaining the distortionless response in the direction of the desired signal and a sidelobe level that is strictly guaranteed to be lower than some given threshold value.

它是通常的最小方差无畸变波束形成算法的改进形式，使阵列输出信号功率最小的同时，保持目标信号方向的无失真响应，并且严格保证旁瓣低于某一给定值，抑制干扰。

The optimized weight is arrived by weighted the minimum variance distortionless response weights of these samples with their post probabilities. In addition, the samples with little post probabilities will be resampled and it improves the robustness of beamforming effectively.

在该算法中期望信号的波达方向被看成一个由若干样点组成的随机变量，利用后验概率对这些样点的最小畸变响应波束成形权值进行加权来取得优化的权值，并对小概率样点进行重采样，有效地提高了波束成形系统的鲁棒性。

A semi-blind MVDR (minimum variance distortionless response) beams forming method belongs to the array signal processing field of a beam former receiving wireless signals.

半盲的最小方差无失真响应波束形成方法属接收无线传播信号的波束器阵列信号处理范畴。

On the basis of theoretical analysis of target diffusion in range-velocity resolution cell, the array signal covariance matrix and noise covariance matrix are estimated from some different cells respectively. The processing results from experimental data in onshore HFSWR with Minimum Variance Distortionless Respose, MUltiple SIgnal Classification and pre-whiten MUSIC respectively show that super-resolution methods can provide better resolution than CBF.

鉴于 HFSWR 工作波长较长、常规波束形成角分辨力较差的缺点，基于目标在距离—多普勒平面分布的理论分析，本文利用相邻距离、多普勒频率单元信号估计阵列协方差阵，并分别利用 MVDR 、 MUSIC 、预白化 MUSIC 方法进行超分辩处理，实测的合作飞机目标数据处理结果表明超分辩方法能明显提高阵列角度分辨力。

Position parameters were obtained from the simulation with the model of towed array.Based on the theory of radiated noise forming, the launch noise was simulated according to test condition in Laboratory,and the result showed the launch impulsion noise obeyed SαS distribution. The simulated noise attenuating in deep sea was analyzed with a sound loss translation model.Minimum variance distortionless response,spatially smoothed MVDR, and beam-space multiple signal classification algorithm were adopted to process the signal, hence the source level, the frequency structure and the location of the launch noise were achieved.

基于试验的实际情况，根据潜艇拖曳阵模型，仿真生成了各水听器阵元与本艇的位置关系；根据噪声源理论模型分析产生雷弹发射模拟噪声，利用SαS分布模拟武器发射冲击噪声，仿真分析模拟噪声在海洋环境中的传播衰减，对阵元信号分别利用最小方差无畸变响应法（MVDR 、空间平滑MVDR以及适应子带的波束域多重信号分类算法进行信号处理，得到发射噪声的声源级、频谱结构和方位。

In §§4.2 and 4.3 we shall be discussing the formal analysis when it can be assumed that the data are normally distributed with constant variance and the rows and columns are independent.

在4.1节，我们应该既考虑通过绘图方式来表示数据又要采用表格式的方法来表达为了任何模式都可能是被决定需要的而且对于所侦察的模式是例外的。

Then the apparent distribution coefficient was calculated, and the differences between different time points and groups were analyzed by analysis of variance.

计算表观分布系数，方差分析法分析不同时间不同处理组之间的差异。

Based on theoretic research, rotary-ditch machine is produced and orthogonal test is carried out in the farm. By variance and extreme deviation analysis on the test result, all the influence factors on ditcher casting performance are gained, superior level and optimum combination are found out, relation curve of performance target along with factor change is provided.

在理论研究的基础上，设计并制作开沟部件，在田间对其进行了正交试验，对试验结果进行极差分析和方差分析，得出各因素对开沟抛土性能的影响，找出各因素的较优水平和最优组合，并给出性能指标随各因素变化的关系曲线。

The result showed that the variance of special combining ability was significantly better than that of the general combining ability in amount of cocoon crop and cocooning rate to newly hatched larvae, meaning that non-additive effect of these two characters was dominant in cross combinations, but additive effect of thousand-cocoon weight was dominant.

结果表明：除千粒茧质量外，产茧量和收蚁结茧率的特殊配合力方差显著地大于一般配合力方差，说明在杂交后代这2个性状的非加性效应占主导地位，而千粒茧质量则以加性效应为主。

In this paper, a new type of statistical feature of the pump dynagraph grey scale, such as the average value, variance, deflection, keenness, energy and entropy.

本文提出提取泵功图的灰度统计特征：灰度的均值、方差、偏度、峰度、能量以及熵。

For a big chunk of credit-card losses; the number of filings (and thus charge-off rates) would be rising again, whether

年美国个人破产法的一个改动使得破产登记急速下降，而后引起了信用卡大规模的亏损。

Eph. 4:23 And that you be renewed in the spirit of your mind

弗四23 而在你们心思的灵里得以更新