平稳函数

Its mean function, variance function and correlation coefficient function can be gained by the method in time domain.

该方法首先在时域进行全程分析，得到相关系数平稳过程的均值函数、方差函数和相关系数函数，然后可以对其进行傅里叶变换、短时傅里叶变换或小波变换，给出相关系数平稳过程的谱密度，同时提出了随机项谱密度和趋势项谱密度的概念。

Stationary process: spectral decomposition of covariance function, spectral decomposition of stationary process, linear time invariant system, ergodic theorem, sampling theorem.

平稳过程：协方差函数的谱分解，平稳过程的谱分解，线性时不变系统，遍历定理，采样定理。

An online mixture of experts is used to divide the HRRP data into several regions within which online Gaussian process classifier make predictions.

通过一种在线混合专家将HRRP数据在线地分割成若干个近似平稳的区域，在各个区域内使用平稳协方差函数的在线高斯过程分类器。

The authors discuss a new numerical simulation method of the downburst wind loads on the basis of the previous research. Firstly, the wind speed is expressed as the sum of an instantaneous mean wind speed and an amplitude-modulating non-stationary fluctuating wind speed. Secondly, a new method based on the modified Osegguera and Bowles/Vicroy model to simulate the mean wind is presented and the fluctuating wind is simulated by a modified spectral representation method.

在将下击暴流风速表达为时变的平均风速和调制的非平稳脉动风速之和的前提下，本文采用基于改进的OBV模型Oseguera and Bowles/Vi-croy(OBV的方法来模拟平均风速，其平均风速直接由改进的OBV模型表达，而不同于已往研究中将平均风速表达为竖向风剖面与时间函数的乘积，并采用结合快速傅里叶变化的谐波叠加法来模拟调制的非平稳脉动风速。

On the assumption that the unevenness of runway profiles along the direction of taxi - ing is a stationary random function,techniques of piecewise constant-speed taxi ing runs and piecewise linear representation of dynamic properties of airplane landing gears are adopted in this paper to approximately simplify the actual nonlinear and nonstationary random vibration prob-lems to the piecewise linear and stationary ones.

在飞机滑行方向跑道路面不平度为平稳随机函数的假设下，采用滑行过程分段等速化、起落架动态特性分段线性化方法，把原非线性非平稳随机振动问题，简化为分段线性平稳随机振动问题。

But we discover that, those most important technical indicators are all stationary processes or their functional transformations. However, stationary process can be computed the frequency is well known.

我们发现，那些最重要的技术指标都是平稳过程或其函数变换，而平稳过程可以统计其频率是已有的结论。

In this dissertation , the methods of prediction and parameters\' estimation based on stationary multivariate autoregressive models AR(p are studied systematically. Some properties of these methods are formulized.In the first part, it introduce some basal conceptions about multidimensional stationary time series, contained the estimation and property of mean vector and auto-covariance function. Then the stable condition of multidimensional AR models are discussed.

本文主要研究了多维平稳序列自回归模型AR的参数估计及其相关的统计性质，具体内容如下：第一部分，介绍了多维平稳时间序列及其均值向量和协方差阵函数的概念，并引入了多维AR模型及其数字特征，在此基础上给出了模型的平稳性条件。

So cooperative controlling of driving force of wheel is a key of trafficability on tough lunar terrain.Based on SQP algorithm,driving force of wheel was optimized. Optimization is based on restriction of moving safely and smoothly.The aim of optimization is to minimize power consume of motors and varying range of driving force.

本文基于序列二次规划算法优化摇杆-转向架式月球车车轮系统驱动力输出，建立保证月球车在月壤平稳安全通过的力学约束方程，以车轮驱动功率和驱动力变化最小为目标函数优化车轮驱动力输出，使月球车平稳前进的同时车轮驱动电机功率消耗最小，这对能源有限的月球车来说是很有意义的。

The data of the company management is essentially an unstationary time sequence. Regarded as a signal, the time sequence is decomposed into different frequency channels. Then wavelet decomposition and reconstruction are used to analyze and forecast the time sequence.

把公司管理上的数据看成一个非平稳的时间序列，利用小波函数将该时间序列分解到不同的频率通道上，然后将分解后的信号当作近似的平稳时间序列，用一些传统的统计方法进行预测。

In the optimization iteration, the levelset function values of nodes are considered as design variables. To computedifferences normally, the Heaviside function is handled for smoothing, theregularized Heaviside function is selected to avoid the oscillation inhomogenizations method, and the results can converge smoothly.

在优化迭代过程中，节点上的Level Set函数值被看作是设计变量，并且为了便于微分计算能够正常进行，对Heaviside函数及其导函数做了光滑化处理，选取了一种正则化的Heaviside函数，避免了均匀化方法中出现的振荡现象，可以平稳地收敛到最终结果。

The absorption and distribution of chromium were studied in ryeusing nutrient culture technique and pot experiment.

采用不同浓度K2CrO4(0，0.4，0.8和1.2 mmol/L)的Hoagland营养液处理黑麦幼苗，测定铬在黑麦体内的亚细胞分布、铬化学形态及不同部位的积累。

By analyzing theory foundation of mathematical morphology in the digital image processing, researching morphology arithmetic of the binary Image, discussing two basic forms for the least structure element: dilation and erosion.

通过分析数学形态学在图像中的理论基础，研究二值图像的形态分析算法，探讨最小结构元素的两种基本形态：膨胀和腐蚀；分析了数学形态学复杂算法的基本原理，把数学形态学的部分并行处理理念引入到家实际应用中。