参数估计

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 modified algorithm estimates the AR model parameters according to the reverberation noise data of the previous blodk,uses the whitener constructed by estimated parameters to filter the reverberation noise data of the current block,and executes the univariate GLRT judgement to the filter...

改进算法根据前一段的混响噪声数据估计AR模型参数，利用估计参数构成的白化器对当前段混响噪声数据进行滤波，并对滤波后数据进行单变量的GLRT检测。与双变量的GLRT算法相比，改进算法有效降低了运算量。最后通过蒙特卡罗仿真给出了改进算法的检测性能分析。

The idea is to construct a homotopy connection of the identification based on ARMAX model with the one based on ARX model.

由于用以估计 ARX模型参数的误差函数是单峰的，因而没有局部最小点问题，这就使得有可能利用它们之间的同伦关系来解决 ARMAX模型参数的估计中的局部最小点问题。

None of the four models could work well in the scenario 2, under explored stock, however they got accurate results in scenario 1, regulated stock. The Schnute model work well in full explored stocks such as scenario 1, 3, 4 and 5, especially in low biomass stocks such as scenario 3, but not suitable to the under explored stocks such as scenario 2. The W-H model generally performed well in all kind of scenarios especially in scenario 1, 4, and 5. In the swordfish, xiphias gladius, fishery, estimation of W-H model and D-Fox model produced MSY about 14000 ton, very near the result of Prager in 1996.The author tentatively explored the suitable fishing condition for the models to stock assessment.

四种剩余产量模型在充分捕捞且管理良好的渔业1中评估效果较好而在捕捞不足的渔业2中效果较差；Schnute模型在充分捕捞的渔业如渔业1、3、4、5、尤其是在低生物量的渔业3中评估效果较好，但不适合评估未充分捕捞的渔业，如渔业2；Walters-Hilborn模型适用于各种渔业，尤其是渔业1、4、5；在过度捕捞渔业中如渔业3、4，模型对参数q的估计较其它参数接近真值；在北大西洋箭鱼渔业的评估中，W-H模型和D-Fox模型对MSY的估计约为14000吨，接近于Prager(1996)的结果。

Firstly, the inversion of the ground motion with the unknown parameters and limited measurements was studied by the substructural identification, and the least-square algorithm of unknown input was built. Secondly, based on the estimated input, structural parameter down to the element level was identified in time domain by extended Kalman filter algorithm. Several cases of a 6-story frame structure are numerically investigated.

首先，使用子结构识别技术，研究了未知参数、观测不完整条件下的地震动输入反演问题，建立了未知输入的最小二乘估计算法；其次，在估计地震动输入的基础上，使用广义Kalman滤波器方法，识别全部单元结构参数。

Thus, we presented a new frequency-selective method for MRS quantification, which estimated the nonlinear and linear parameters of the selected components baaed on total least squares and forward-backward APES respectively.

为此本文提出了一种基于频率选择的波谱信号量化方法，该方法通过全局最小乘方法来估计波谱信号的非线性参数，又结合前向和后向的APES方法来估计其线性参数。

Base on the results computed by the Discrete Fourier Transform in demodulation and dispreading, the scheme can estimate accurately the parameters such as frequency, amplitude and initial phase of single tone jamming by analyzing two spectra lines having higher energy than other.

提出了一种精确估计多载波扩频系统中单音干扰参数的新方法，利用解调解扩中离散傅里叶变换的计算结果，通过选取其中能量最大的两条谱线进行分析，能够对单音干扰的频率、振幅以及初始相位等参数进行精确的估计。

Prove it's admissibility and give Hemmerle and Brantle's method of choosing the ridge parameters.

证明其容许性并利用Hemmerle和Brantle用于确定广义岭估计参数的方法给出极小化均方误差的无偏估计法选取岭参数。

A model consisting of deception parameters is presented to estimate the states of target as well as the states of range gate pull-off in pulse Doppler radar.

建立一个包含欺骗过程参数的滤波模型，在估计目标状态的同时，对目标距离拖引欺骗的相关参数进行估计。

On the approximate uncorrelation property of DWT coefficients of LMSV process in the same scale and different scales, first the quasi maximum likelihood estimation method of parameters and the estimation method of volatility process of LMSV model are presented.

根据小波变换可将过程分解到不同的尺度上以及LMSV过程同一尺度下和不同尺度下DWT系数的近似不相关性，提出了建立局部似然函数的方法，又根据DWT系数和MODWT系数之间的关系，将局部似然函数表示为模型参数和局部小波方差估计的形式，并用该方法对中国股市收益进行了时变LMSV模型参数的估计。

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