矿业 矿井 外文翻译 外文文献 英文文献 基于PCA技术核心的打包和变换的矿井提升机失误的发现.doc
《矿业 矿井 外文翻译 外文文献 英文文献 基于PCA技术核心的打包和变换的矿井提升机失误的发现.doc》由会员分享,可在线阅读,更多相关《矿业 矿井 外文翻译 外文文献 英文文献 基于PCA技术核心的打包和变换的矿井提升机失误的发现.doc(15页珍藏版)》请在三一办公上搜索。
1、外文翻译部分:英文原文Mine-hoist fault-condition detection based onthe wavelet packet transform and kernel PCAAbstract: A new algorithm was developed to correctly identify fault conditions and accurately monitor fault development in a mine hoist. The new method is based on the Wavelet Packet Transform (WPT) an
2、d kernel PCA (Kernel Principal Component Analysis, KPCA). For non-linear monitoring systems the key to fault detection is the extracting of main features. The wavelet packet transform is a novel technique of signal processing that possesses excellent characteristics of time-frequency localization. I
3、t is suitable for analysing time-varying or transient signals. KPCA maps the original input features into a higher dimension feature space through a non-linear mapping. The principal components are then found in the higher dimension feature space. The KPCA transformation was applied to extracting th
4、e main nonlinear features from experimental fault feature data after wavelet packet transformation. The results show that the proposed method affords credible fault detection and identification.Key words: kernel method; PCA; KPCA; fault condition detection1 IntroductionBecause a mine hoist is a very
5、 complicated andvariable system, the hoist will inevitably generate some faults during long-terms of running and heavy loading. This can lead to equipment being damaged,to work stoppage, to reduced operating efficiency andmay even pose a threat to the security of mine personnel. Therefore, the ident
6、ification of running fault shas become an important component of the safety system. The key technique for hoist condition monitoring and fault identification is extracting information from features of the monitoring signals and then offering a judgmental result. However, there are many variables to
7、monitor in a mine hoist and, also , there are many complex correlations between thevariables and the working equipment. This introduce suncertain factors and information as manifested by complex forms such as multiple faults or associated faults, which introduce considerable difficulty to fault diag
8、nosis and identification1. There are currently many conventional methods for extracting mine hoist fault features, such as Principal Component Analysis(PCA) and Partial Least Squares (PLS)2. These methods have been applied to the actual process. However, these methods are essentially a linear transf
9、ormation approach. But the actual monitoring process includes nonlinearity in different degrees. Thus, researchers have proposed a series of nonlinearmethods involving complex nonlinear transformations. Furthermore, these non-linear methods are confined to fault detection: Fault variable separation
10、and fault identification are still difficult problems.This paper describes a hoist fault diagnosis featureexaction method based on the Wavelet Packet Transform(WPT) and kernel principal component analysis(KPCA). We extract the features by WPT and thenextract the main features using a KPCA transform,
11、which projects low-dimensional monitoring datasamples into a high-dimensional space. Then we do adimension reduction and reconstruction back to thesingular kernel matrix. After that, the target feature isextracted from the reconstructed nonsingular matrix.In this way the exact target feature is dist
12、inct and stable.By comparing the analyzed data we show that themethod proposed in this paper is effective.2 Feature extraction based on WPT andKPCA2.1 Wavelet packet transformThe wavelet packet transform (WPT) method3,which is a generalization of wavelet decomposition, offers a rich range of possibi
13、lities for signal analysis. The frequency bands of a hoist-motor signal as collected by the sensor system are wide. The useful information hides within the large amount of data. In general, some frequencies of the signal are amplified and some are depressed by the information. That is tosay, these b
14、roadband signals contain a large amountof useful information: But the information can not bedirectly obtained from the data. The WPT is a finesignal analysis method that decomposes the signalinto many layers and gives a etter resolution in thetime-frequency domain. The useful informationwithin the d
15、ifferent requency ands will be expressed by different wavelet coefficients after thedecomposition of the signal. The oncept of “energy information” is presented to identify new information hidden the data. An energy igenvector is then used to quickly mine information hiding within the large amount o
16、f data.The algorithm is: Step 1: Perform a 3-layer wavelet packet decomposition of the echo signals and extract the signal characteristics of the eight frequency components ,from low to high, in the 3rd layer. Step 2: Reconstruct the coefficients of the waveletpacket decomposition. Use 3 j S (j=0, 1
17、, , 7) to denote the reconstructed signals of each frequencyband range in the 3rd layer. The total signal can thenbe denoted as: (1)Step 3: Construct the feature vectors of the echosignals of the GPR. When the coupling electromagneticwaves are transmitted underground they meetvarious inhomogeneous m
18、edia. The energy distributing of the echo signals in each frequency band willthen be different. Assume that the corresponding energyof 3 j S (j=0, 1, , 7) can be represented as3 j E (j=0, 1, , 7). The magnitude of the dispersedpoints of the reconstructed signal 3 j S is: jk x (j=0,1, , 7; k=1, 2, ,
19、n), where n is the length of thesignal. Then we can get: (2)Consider that we have made only a 3-layer waveletpackage decomposition of the echo signals. To makethe change of each frequency component more detailedthe 2-rank statistical characteristics of the reconstructedsignal is also regarded as a f
20、eature vector: (3)Step 4: The 3 j E are often large so we normalize them. Assume that, thus the derived feature vectors are, at last:T= (4) The signal is decomposed by a wavelet packageand then the useful characteristic information featurevectors are extracted through the process given above.Compare
21、d to other traditional methods, like the Hilberttransform, approaches based on the WPT analysisare more welcome due to the agility of the processand its scientific decomposition.2.2 Kernel principal component analysisThe method of kernel principal component analysisapplies kernel methods to principa
22、l component analysis45.The principalcomponent is the element at the diagonal afterthe covariance matrix,has beendiagonalized. Generally speaking, the first N valuesalong the diagonal, corresponding to the large eigenvalues,are the useful information in the analysis.PCA solves the eigenvalues and eig
23、envectors of thecovariance matrix. Solving the characteristic equation6: (5)where the eigenvalues ,and the eigenvectors, is essence of PCA.Let the nonlinear transformations, : RN F ,x X , project the original space into feature space,F. Then the covariance matrix, C, of the original space has the fo
24、llowing form in the feature space: (6)Nonlinear principal component analysis can beconsidered to be principal component analysis ofin the feature space, F. Obviously, all the igenvaluesof C and eigenvectors, V F 0 satisfyV = V . All of the solutions are in the subspacethat transforms from (7)There i
- 配套讲稿:
如PPT文件的首页显示word图标,表示该PPT已包含配套word讲稿。双击word图标可打开word文档。
- 特殊限制:
部分文档作品中含有的国旗、国徽等图片,仅作为作品整体效果示例展示,禁止商用。设计者仅对作品中独创性部分享有著作权。
- 关 键 词:
- 矿业 矿井 外文翻译 外文文献 英文文献 基于PCA技术核心的打包和变换的矿井提升机失误的发现 外文 翻译 文献 英文 基于 PCA 技术 核心 打包 变换 提升 失误 发现
链接地址:https://www.31ppt.com/p-3929302.html