| 1. | Estimate a stationary process under left censoring 对左截断数据估计平稳序列 |
| 2. | The relationship of the spca , pca and kpca are established . according to the covariance stationary processes , spca arithmetic also has certain stability and convergent similar to pca arithmetic 由协方差平稳过程,得到谱主成分分析算法也有类似于主成分分析算法的稳定性和收敛性。 |
| 3. | In this paper , we have systematically investigated the relations for strictly stationary processes , wide stationary processes , martingales ang markov processes , many interesting results of interest are obtained 摘要系统研究了严平稳过程,宽平稳过程与鞅及马氏过程的相互关系,得到许多有趣的结果。 |
| 4. | In this thesis , based on principal component analysis ( pca ) , covariance stationary processes and spectral analysis theory of linear operator , spectral principal component analysis ( spca ) is put forward 在主成分分析的基础上,基于协方差平稳过程理论和线性算子谱分析理论,本文提出了谱主成分分析。 |
| 5. | If the covariance stationary processes are one dimension , for given data , covariance function and spectral density function can be estimated , and there is no need to select kernel function and its parameters 如果协方差平稳随机过程的状态是一维的,对给定的样本点,给出了协方差函数的估计和其对应谱(密度)函数估计,而不必选择核函数及其参数。 |
| 6. | The proposed approach can effectively monitor the changing trends of the dominant frequency and energy as well as the process variable contributions , and is feasible for non - stationary process monitoring , fault detection and localization 该方法能有效地监控过程系统中主导成分的频率、能量的变化趋势以及过程变量的贡献度,适合于非稳态过程监控以及故障检测与定位。 |
| 7. | Owing to the fact that the wavelet transformation possesses localization and implicit difference property , the suthors show that after wavelet tansformation , the fractionally differenced process and the harmonizable periodically correlated process may be changed into stationary processes 利用小波的局部性及暗含的差分性质,证明了在小波变换后,分数差分平稳过程和可调和周期相关过程是平稳的。 |
| 8. | Two key issues of fault diagnosis for the pump valves of reciprocating pump are extracting the fault feature information of stationary process efficiently from system feature signals and identifying the specific faults correctly with analysis of causes 在故障诊断领域,还有许多问题亟待解决。目前,往复泵泵阀故障诊断需要解决的两个关键问题是有效提取往复泵工作时非平稳时变信号中的故障特征和将故障特征准确分类。 |
| 9. | Cointegration method is a new algorithm developed in economics area for modelling non - stationary economical and financial processes . it can generate a stationary process based on a linear combination of a set of non - stationary processes if these non - stationary processes have long - term balanced relation 协整理论是处理非平稳时间序列的有力工具,可通过线性组合,将具有长期均衡关系的多个非平稳时间序列生成一个平稳序列。 |
| 10. | Granger received the nobel prize , because their cointegration theory had solved two difficult problems , the time - varying volatility and non - stationary in the time series analysis field . in this paper , will introduce the normal knowledge of cointegration theory , and emphatically depict the possibility of applying cointegration algorithm to condition monitoring and fault diagnosis for engineering systems , which are non - stationary processes . it is well known that non - stationary system behavior causes grave difficulties on system modeling and condition monitoring due to the time - dependent statistics 2003年,诺贝尔经济学奖颁给了在时间序列计量经济学研究领域做出突破性贡献的两位美国经济学家,罗伯特?恩格尔( robertf . engle )和克莱夫?格兰杰( clivewj . granger ) ,以表彰他们提出的协整理论解决了时间序列分析中的两个难题,即异方差( time - varyingvolatility )与非平稳性( non - stationary ) 。 |