提取信息

Compared with the traditional numerical method,the periodic orbit extracted by the analytic approach is more accurate,requires smaller memory size and is more applicable in real time systems;Furthermore,it is more suitable for stable analysis and control of the systems.

与传统的数值提取法相比，所提出的解析法具有提取的周期轨道精确度高、周期轨道信息的存储量小、便于实时应用、易于进行稳定性分析和控制等优点。

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。

There are three main methods in face localization: localization according to face outline, localization according to complexion and localization according to templates constructed by some standard sample images. As to feature extraction, it can be divided into two parts because face features can be divided into geometrical features and algebraic features. While extracting geometrical features, the features of eyes, nose, mouth, eyebrows can be gained by some image processes: binary, sharpen, smooth, projection, calculating gradient and so on. In order to extract algebraic features, we can do some mathematical transformation for the digital images such as singular value decomposition, K-L transformation.

在人脸检测部分，目前存在的方法有利用人脸的几何轮廓进行检测、利用人脸的肤色信息进行检测、构造标准人脸模板进行匹配检测等等；在人脸特征提取部分，可以用一些图像处理的方法如投影、二值化、求梯度图像等提取人脸中各特征器官如眼睛、鼻子、嘴巴等的几何特征，另外也可以借助于数学变换，求取人脸图像的一些代数特征，如对图像进行奇异值分解，以奇异值代表图象的特征，或对图像进行K-L变换，以图像在构造的特征空间上的投影系数作为图像的特征等；在识别部分，可以通过距离度量或相似度来判断输入图像与样本图像的匹配程度，还可以通过神经网络方法进行人脸的识别。

The technology for construction of the road detector from edge detectors was described, the approach based on multivariate statistical hypothesis tests was applied to information fusion of SAR images, and the extracting result from two traditional Tupin methods and that from the method proposed in this paper were compared with each other.

首先，介绍了用边缘探测器构造道路探测器的方法；然后，将多参数统计假设检验的方法应用到全极化影像的信息融合中，并将该方法提取的结果与传统Tupin法提取的结果进行了比较。

The box-counting dimension,multi-fractal dimensions and discharge centrobaric characteristics of the PD pictures are also extracted, and the characteristic variables are classified by RBF network.

由于图谱中含有局部放电丰富的信息，因此局放特征通常从二维和三维图谱φ-q-n(放电工频相位φ、放电幅值q和放电次数n)中提取，提取的特征有：统计特征[2]、分形特征[3-5]、小波特征[6-7]、矩特征[8]等。

Keywords can be considered as a set of words which are important and subject correlated cohesively in a document. Therefore, an automatic keyword extraction method based on density clustering is proposed in this paper. Web pages are segmented, and the words are clustered based on their co-occurrence. Co-occurrence relations between words are analyzed, and keywords that capture the main topics of the document are extracted.

由于关键词是文章中较重要且主题关联较凝聚的词的集合，因此提出一种基于密度聚类模式的中文新闻网页关键词提取方法，根据词语之间的共现信息，对网页分词后的词语进行聚类，在分析词语关联度的基础上提取出反映新闻主题的关键词。

The ordinary edge detection methods such as Sobel and Canny operators are immune to noise, which result in cophasal axes discontinuity due to lack of edge information caused by noise.

由于边缘检测中常用的Sobel算子和Canny算子检测同相轴时对噪声免疫差，常因噪声因素引起边缘信息缺失导致同相轴提取不连续，本文采用中值滤波并对Sobel算子进行改进，对地震剖面图进行预处理，结合均方差自动确定阈值并进行异常检测，提取完整同相轴。

The ordinary edge detection methods such as Sobel and Canny operators are immune to noise, which result in cophasal axes discontinuity due to lack of edge information caused by noise. In order to extract cophasal axes more continuous and immune to noise, a novel approach is developed based on edge detection. Firstly, the median filter and improved Sobel method are used to preprocess seismic section images. Secondly, the threshold value is determined automatically based on variance to detect abnormal information. Finally, the complete cophasal axes are extracted after a post-processing.

由于边缘检测中常用的Sobel算子和Canny算子检测同相轴时对噪声免疫差，常因噪声因素引起边缘信息缺失导致同相轴提取不连续，本文采用中值滤波并对Sobel算子进行改进，对地震剖面图进行预处理，结合均方差自动确定阈值并进行异常检测，提取完整同相轴。

Using Landsat TM data, based on the spectral character analysis of main land-use types, different feature models under strong land disturbance in Antaibao opencast coal mine were set up. Vegetation higher cover area, vegetation lower cover area, denudation and cumuli area, excavation and transport area and slope area in Antaibao were extracted. The information of areas with higher vegetation cover and lower vegetation cover were detected by NDVI (normalized difference vegetation index).

该研究利用Landsat TM数据，以安太堡大型露天煤矿为例，在对地物光谱特征深入分析的基础上，设计了大型露天矿区土地剧烈扰动下不同地物特征提取模型，提取了安太堡露天矿区植被高覆盖区、植被低覆盖区、剥离堆垫区、采煤运煤区及边坡区等不同地物信息。

The watermark information which is generated by subsidiary secret keys of binary sequence can prove copyright of composer intuitionally.

提取水印信息的时候，无需原始音频信号的辅助，首先提取出子密钥水印图像，再与先前的子密钥叠加恢复水印。

As she looked at Warrington's manly face, and dark, melancholy eyes, she had settled in her mind that he must have been the victim of an unhappy attachment.

每逢看到沃林顿那刚毅的脸，那乌黑、忧郁的眼睛，她便会相信，他一定作过不幸的爱情的受害者。

Maybe they'll disappear into a pothole.

也许他们将在壶穴里消失