离散

There are two fundamentally different dynamical systems: those with discrete time variable and those with continuous time variable.

本文主要针对离散时间动力系统的动力学性质研究，包括差分方程及离散人工神经网络两个方面的研究。

The discrete element method and the finite element method have their own advantages and weaknesses. Basically, the DEM was developed for predicting the failure problems accompanying with the transition from continuum to non-continuum media. However, it is not accurate to calculate the problem of continuum media. The FEM may forecast the failure area of the material reasonably, while it is hard to calculate the failure process in brittle media. Therefore it becomes a good choice to combine the two methods to construct a hybrid model.

离散元法和有限元法等数值计算方法各有其优势，同时也都存在不足之处：离散元法适于处理由连续介质向非连续介质转化的破坏问题，但对于连续体计算结果精度不高；有限元法适于预测材料破坏的区域，但难以直接用于计算脆性材料破坏过程，因此将两种方法结合可以形成一种较好的混合模型。

If the topology is fixed and time-invariant, the consensus value of discrete-time systems also globally asymptotically converges to the convex combination of initial states, which is identical to continuous systems.

如果多智能体网络系统的拓扑结构没有改变，在离散状态下系统的一致平衡点仍收敛于初始状态的凸组合，并且离散状态下系统的一致平衡点与连续状态下系统的一致平衡点相等。

A convex combination condition and a switching strategy are derived.

针对离散单时滞切换系统，提出了一个使系统渐近稳定的充分性条件，给出了该系统的无记忆状态反馈镇定和无记忆输出反馈镇定，并将结果推广到不确定离散时滞切换系统的鲁棒镇定。

In this paper a method based on discrete wavelet transform and discrete cosine transform is presented to compress color image.

中文摘要：本文给出了一种基于离散小波变换和离散余弦变换的彩色图像压缩方法。

Methods of Discrete Cosine Transformation and Discrete Wavelet Transformation are two ways, and also make a comparison of these two ways.

采用的方法是离散余弦变换和离散小波变换两种方法，并且还对这两种方法进行了比较。

Using cubic spline interpolation function, we construct a finite element model to approximate the nonlinear Schr〓dinger equation, and provide a complete discrete scheme with the conservation properties of mass and energy.

本章从应用角度出发，着重讨论孤波形式的解的计算，为此我们利用三次样条函数的插值基函数构造出非线性薛定谔方程的一个有限元离散模型，给出了具有保质量与能量守恒的全离散计算格式。

Proper combinations of number of outcomes, discrete step size, and scaling of the random variable, the discrete cumulate percentage distribution and discrete percentage density will converge to the continuous cumulative probability distribution and probability density function respectively.

适当之出现或试验次数或取样数量、散化阶梯大小、随机变数缩放比例可使离散累积百分比分布及离散百分比密度趋近于连续的累积机率分布及机率密度函数。

It is based on the discrete model of finite analysis to get curvature ,normal vector, direction and geodesic curve,then to analyze and design the structure.

基于有限元分析的离散模型，将离散微分几何领域的最新成果运用于膜结构设计，求解曲面曲率，法向量，主方向及测地线，进行结构分析设计。

Firstly expound the structure of the OFDM system, then analysis the working principle of OFDM communication and research into the key technologies in OFDM system: string conversion, sub-carrier modulation and demodulation, inverse Discrete Fourier Transformation, Discrete Fourier Transformation, cyclic prefix Insert, etc.

该文首先阐述了OFDM系统的结构，分析了OFDM通信系统的工作原理，研究了OFDM系统实现过程中串并转换、子载波调制解调、离散逆傅里叶变换、离散傅里叶变换、循环前缀插入等关键技术。

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。