混沌

By using the characteristic that the distribution of chaotic obit in the phase space is nonlinear, a method for constructing S-box based on iterating chaotic maps was proposed.

然后利用混沌系统在相空间的高度非线性，提出了一种迭代混沌映射的S盒构造方法。

The frequency characteristics of chaotic system are studied by using Oppenheim's chaotic masking.

利用Oppenheim的混沌伪装方案对混沌系统的频率特性进行了分析。

It is found that the change of the frequency characteristics of chaotic system occurs mainly at the frequency band of the chaotic system, in which the input signal exists. The amplitude of the input signal doesn't influence the distortion of the output signal when masking signal is extracted by Oppenheim's chaotic masking.

研究发现，混沌系统频率特性的变化主要发生在输入信号的频率位於混沌系统频带内的情况下；输入信号幅度的大小，不影响输出信号的失真。

Experimental results show output signals' characteristic is identical to the Logistic Map's.

实验结果表明，输出混沌信号与logistic映射的分析结果一致，这说明了数字混沌产生器的有效性。

Based on the parametric solutions of a Sylvester matrix equation, the parametric expressions of the gain matrices of synchronization dynamic observer in the nonlinear feedback chaotic systems are presented, in which the parameter vectors offer all the design degrees that can be selected to satisfy some performances, such as robustness.

基于Sylvester矩阵方程的参数化解，给出了非线性反馈混沌系统的同步动态观测器矩阵的所有参数化表达式，其所含参量为混沌系统控制设计提供了全部自由度，可适当选择自由参量满足某些鲁棒性指标。

A hyperchaotic system could be made to run stably in a certain periodic orbit by this method.

混沌和超混沌系统奇异吸引子中存在着无穷多个不稳定的周期轨道。

Based on the concept of frequency analysis in periodic orbit theory and matrix principle, a method of changing fundamental frequency of chaotic systems is put forward.

文中基于混沌吸引子周期轨道理论的频域分析概念和矩阵分析原理提出了一种混沌系统基波频率变换方法。

In this paper, first, a method of fundamental frequency transformation for chaotic systems is proposed based on the concept of frequency domain analysis in the periodic orbit theory of chaotic attractors and on the matrix principle.

文中基于混沌吸引子周期轨道理论的频域分析概念和矩阵分析原理，提出了一种混沌系统基波频率变换方法。

In other cases, The simulation gives that as the coefficient of square velocity item varies from small to large the respondence of the chaos system change from chaos change to stable periodic orbit and then to dissipation movement.

然后通过仿真实例证实，在其他情况下，当速度平方项系数从小到大变化时，系统的混沌响应经历了从混沌突变到稳定的周期运动在突变到发散运动的过程。

Firstly,the wavelet-based contourlet coding using an SPIHT-like algorithm is utilized on the plain image,and as a result,the compressed datum stream could be achieved which is then mapped to a 3D bit matrix. Afterward,a chaotic sequence is generated by Lorenz chaotic map,and it is preprocessed to a bit sequence which is used to permute and substitute the elements of the 3D bit matrix achieved above. In the end,the processed 3D matrix is mapped back to datum stream,and the encrypted compressed image could be achieved if decoding and inverse transform are performed on the datum stream.

首先采用基于小波的Contourlet变换的类等级树集合分割编码算法对明文图像进行压缩，得到压缩数据流，然后将压缩数据流映射为一个三维位矩阵；利用Lorenz混沌映射产生混沌序列，并对其进行预处理得到比特值序列，根据比特值序列对上述三维位矩阵进行置乱和替代操作；将置乱和替代后的位矩阵重新映射为数据流，并对其进行解码和反变换操作，得到加密后的压缩图像。

On the other hand, the more important thing is because the urban housing is a kind of heterogeneity products.

另一方面，更重要的是由于城市住房是一种异质性产品。

Climate histogram is the fall that collects place measure calm value, cent serves as cross axle for a few equal interval, the area that the frequency that the value appears according to place is accumulated and becomes will be determined inside each interval, discharge the graph that rise with post, also be called histogram.

气候直方图是将所收集的降水量测定值，分为几个相等的区间作为横轴，并将各区间内所测定值依所出现的次数累积而成的面积，用柱子排起来的图形，也叫做柱状图。