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Olive Leaf Disease Detection via Wavelet Transform and Feature Fusion of Pre-Trained Deep Learning Models
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作者 Mahmood A.Mahmood Khalaf Alsalem 《Computers, Materials & Continua》 SCIE EI 2024年第3期3431-3448,共18页
Olive trees are susceptible to a variety of diseases that can cause significant crop damage and economic losses.Early detection of these diseases is essential for effective management.We propose a novel transformed wa... Olive trees are susceptible to a variety of diseases that can cause significant crop damage and economic losses.Early detection of these diseases is essential for effective management.We propose a novel transformed wavelet,feature-fused,pre-trained deep learning model for detecting olive leaf diseases.The proposed model combines wavelet transforms with pre-trained deep-learning models to extract discriminative features from olive leaf images.The model has four main phases:preprocessing using data augmentation,three-level wavelet transformation,learning using pre-trained deep learning models,and a fused deep learning model.In the preprocessing phase,the image dataset is augmented using techniques such as resizing,rescaling,flipping,rotation,zooming,and contrasting.In wavelet transformation,the augmented images are decomposed into three frequency levels.Three pre-trained deep learning models,EfficientNet-B7,DenseNet-201,and ResNet-152-V2,are used in the learning phase.The models were trained using the approximate images of the third-level sub-band of the wavelet transform.In the fused phase,the fused model consists of a merge layer,three dense layers,and two dropout layers.The proposed model was evaluated using a dataset of images of healthy and infected olive leaves.It achieved an accuracy of 99.72%in the diagnosis of olive leaf diseases,which exceeds the accuracy of other methods reported in the literature.This finding suggests that our proposed method is a promising tool for the early detection of olive leaf diseases. 展开更多
关键词 Olive leaf diseases wavelet transform deep learning feature fusion
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Weak Fault Feature Extraction of the Rotating Machinery Using Flexible Analytic Wavelet Transform and Nonlinear Quantum Permutation Entropy
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作者 Lili Bai Wenhui Li +3 位作者 He Ren Feng Li TaoYan Lirong Chen 《Computers, Materials & Continua》 SCIE EI 2024年第6期4513-4531,共19页
Addressing the challenges posed by the nonlinear and non-stationary vibrations in rotating machinery,where weak fault characteristic signals hinder accurate fault state representation,we propose a novel feature extrac... Addressing the challenges posed by the nonlinear and non-stationary vibrations in rotating machinery,where weak fault characteristic signals hinder accurate fault state representation,we propose a novel feature extraction method that combines the Flexible Analytic Wavelet Transform(FAWT)with Nonlinear Quantum Permutation Entropy.FAWT,leveraging fractional orders and arbitrary scaling and translation factors,exhibits superior translational invariance and adjustable fundamental oscillatory characteristics.This flexibility enables FAWT to provide well-suited wavelet shapes,effectively matching subtle fault components and avoiding performance degradation associated with fixed frequency partitioning and low-oscillation bases in detecting weak faults.In our approach,gearbox vibration signals undergo FAWT to obtain sub-bands.Quantum theory is then introduced into permutation entropy to propose Nonlinear Quantum Permutation Entropy,a feature that more accurately characterizes the operational state of vibration simulation signals.The nonlinear quantum permutation entropy extracted from sub-bands is utilized to characterize the operating state of rotating machinery.A comprehensive analysis of vibration signals from rolling bearings and gearboxes validates the feasibility of the proposed method.Comparative assessments with parameters derived from traditional permutation entropy,sample entropy,wavelet transform(WT),and empirical mode decomposition(EMD)underscore the superior effectiveness of this approach in fault detection and classification for rotating machinery. 展开更多
关键词 Rotating machinery quantum theory nonlinear quantum permutation entropy Flexible Analytic wavelet transform(FAWT) feature extraction
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Dual-stream coupling network with wavelet transform for cross-resolution person re-identification
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作者 SUN Rui YANG Zi +1 位作者 ZHAO Zhenghui ZHANG Xudong 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2023年第3期682-695,共14页
Person re-identification is a prevalent technology deployed on intelligent surveillance.There have been remarkable achievements in person re-identification methods based on the assumption that all person images have a... Person re-identification is a prevalent technology deployed on intelligent surveillance.There have been remarkable achievements in person re-identification methods based on the assumption that all person images have a sufficiently high resolution,yet such models are not applicable to the open world.In real world,the changing distance between pedestrians and the camera renders the resolution of pedestrians captured by the camera inconsistent.When low-resolution(LR)images in the query set are matched with high-resolution(HR)images in the gallery set,it degrades the performance of the pedestrian matching task due to the absent pedestrian critical information in LR images.To address the above issues,we present a dualstream coupling network with wavelet transform(DSCWT)for the cross-resolution person re-identification task.Firstly,we use the multi-resolution analysis principle of wavelet transform to separately process the low-frequency and high-frequency regions of LR images,which is applied to restore the lost detail information of LR images.Then,we devise a residual knowledge constrained loss function that transfers knowledge between the two streams of LR images and HR images for accessing pedestrian invariant features at various resolutions.Extensive qualitative and quantitative experiments across four benchmark datasets verify the superiority of the proposed approach. 展开更多
关键词 cross-resolution feature invariant learning person re-identification residual knowledge transfer wavelet transform
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SIGNAL FEATURE EXTRACTION BASED UPON INDEPENDENT COMPONENT ANALYSIS AND WAVELET TRANSFORM 被引量:7
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作者 JiZhong JinTao QinShuren 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2005年第1期123-126,共4页
It is an important precondition for machine fault diagnosis that vibrationsignal can be extracted effectively. Based on the characteristic of noise interfused during thecourse of sampling vibration signal, independent... It is an important precondition for machine fault diagnosis that vibrationsignal can be extracted effectively. Based on the characteristic of noise interfused during thecourse of sampling vibration signal, independent component analysis (ICA) method is combined withwavelet to de-noise. Firstly, The sampled signal can be separated with ICA, then the function offrequency band chosen with multi-resolution wavelet transform can be used to judge whether thestochastic disturbance singular signal is interfused. By these ways, the vibration signals can beextracted effectively, which provides favorable condition for subsequent feature detection ofvibration signal and fault diagnosis. 展开更多
关键词 Independent component analysis (ICA) wavelet transform DE-NOISING FAULTDIAGNOSIS feature extraction
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A novel signal feature extraction technology based on empirical wavelet transform and reverse dispersion entropy 被引量:3
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作者 Yu-xing Li Shang-bin Jiao Xiang Gao 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2021年第5期1625-1635,共11页
Feature extraction is an important part of signal processing,which is significant for signal detection,classification,and recognition.The nonlinear dynamic analysis method can extract the nonlinear characteristics of ... Feature extraction is an important part of signal processing,which is significant for signal detection,classification,and recognition.The nonlinear dynamic analysis method can extract the nonlinear characteristics of signals and is widely used in different fields.Reverse dispersion entropy(RDE)proposed by us recently,as a nonlinear dynamic analysis method,has the advantages of fast computing speed and strong anti-noise ability,which is more suitable for measuring the complexity of signal than traditional permutation entropy(PE)and dispersion entropy(DE).Empirical wavelet transform(EWT),based on the theory of wavelet analysis,can decompose a complex non-stationary signal into a number of empirical wavelet functions(EWFs)with compact support set spectrum,which has better decomposition performance than empirical mode decomposition(EMD)and its improved algorithms.Considering the advantages of RDE and EWT,on the one hand,we introduce EWT into the field of underwater acoustic signal processing and fault diagnosis to improve the signal decomposition accuracy;on the other hand,we use RDE as the features of EWFs to improve the signal separability and stability.Finally,we propose a novel signal feature extraction technology based on EWT and RDE in this paper.Experimental results show that the proposed feature extraction technology can effectively extract the complexity features of actual signals.Moreover,it also has higher distinguishing ability for different types of signals than five latest feature extraction technologies. 展开更多
关键词 feature extraction Empirical mode decomposition Empirical wavelet transform Permutation entropy Reverse dispersion entropy
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Gauss linear frequency modulation wavelet transforms and its application to seismic phases identification
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作者 刘希强 周惠兰 +3 位作者 曹文海 李红 李永红 季爱东 《Acta Seismologica Sinica(English Edition)》 CSCD 2002年第6期636-645,共10页
Based on the characteristics of gradual change style seismic signal onset which has more high frequency signal components but less magnitude, this paper selects Gauss linear frequency modulation wavelet as base functi... Based on the characteristics of gradual change style seismic signal onset which has more high frequency signal components but less magnitude, this paper selects Gauss linear frequency modulation wavelet as base function to study the change characteristics of Gauss linear frequency modulation wavelet transform with difference wavelet and signal parameters, analyzes the error origin of seismic phases identification on the basis of Gauss linear frequency modulation wavelet transform, puts forward a kind of new method identifying gradual change style seismic phases with background noise which is called fixed scale wavelet transform ratio, and presents application examples about simulation digital signal and actual seismic phases recording onsets identification. 展开更多
关键词 Gauss linear frequency modulation wavelet wavelet transform gradual change style seismic sig-nal onset identification
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Radar Signal Intra-Pulse Feature Extraction Based on Improved Wavelet Transform Algorithm 被引量:2
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作者 Wenxu Zhang Fuli Sun Bing Wang 《International Journal of Communications, Network and System Sciences》 2017年第8期118-127,共10页
With the new system radar put into practical use, the characteristics of complex radar signals are changing and developing. The traditional analysis method of one-dimensional transformation domain is no longer applica... With the new system radar put into practical use, the characteristics of complex radar signals are changing and developing. The traditional analysis method of one-dimensional transformation domain is no longer applicable to the modern radar signal processing, and it is necessary to seek new methods in the two-dimensional transformation domain. The time-frequency analysis method is the most widely used method in the two-dimensional transformation domain. In this paper, two typical time-frequency analysis methods of short-time Fourier transform and Wigner-Ville distribution are studied by analyzing the time-frequency transform of typical radar reconnaissance linear frequency modulation signal, aiming at the problem of low accuracy and sen-sitivity to the signal noise of common methods, the improved wavelet transform algorithm was proposed. 展开更多
关键词 Intra-Pulse feature Extraction TIME-FREQUENCY Analysis Short-Time FOURIER transform Wigner-Ville Distribution wavelet transform
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EEG Signal Denoising and Feature Extraction Using Wavelet Transform in Brain Computer Interface 被引量:1
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作者 吴婷 颜国正 +1 位作者 杨帮华 孙虹 《Journal of Donghua University(English Edition)》 EI CAS 2007年第5期641-645,共5页
Electroencephalogram(EEG) signal preprocessing is one of the most important techniques in brain computer interface(BCI).The target is to increase signal-to-noise ratio and make it more favorable for feature extraction... Electroencephalogram(EEG) signal preprocessing is one of the most important techniques in brain computer interface(BCI).The target is to increase signal-to-noise ratio and make it more favorable for feature extraction and pattern recognition.Wavelet transform is a method of multi-resolution time-frequency analysis,it can decompose the mixed signals which consist of different frequencies into different frequency band.EEG signal is analyzed and denoised using wavelet transform.Moreover,wavelet transform can be used for EEG feature extraction.The energies of specific sub-bands and corresponding decomposition coefficients which have maximal separability according to the Fisher distance criterion are selected as features.The eigenvector for classification is obtained by combining the effective features from different channels.The performance is evaluated by separability and pattern recognition accuracy using the data set of BCI 2003 Competition,the final classification results have proved the effectiveness of this technology for EEG denoising and feature extraction. 展开更多
关键词 脑电图 预处理 小波变换 特征提取
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ADAPTIVE MULTISCALE EDGE DETECTION BASED ON VISION FEATURE OF EDGE AND WAVELET TRANSFORM
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作者 Yang Xuan Liang Dequn (Laboratory of Image Process and Pattern Recognition, Xi’an Jiaotong University, Xi’an 710049) 《Journal of Electronics(China)》 1999年第2期104-108,共5页
A new rnultiscale edge detection method is presented, which is based on an effective edge measure. The effective edge measure, used to adaptively adjust the scales of wavelet transform, is defined using the novel feat... A new rnultiscale edge detection method is presented, which is based on an effective edge measure. The effective edge measure, used to adaptively adjust the scales of wavelet transform, is defined using the novel features of image edge obtained from human being vision characteristics. Finally, two experiments show that the proposed algorithm appears to work well. 展开更多
关键词 COMPUTER VISION EDGE features wavelet transform EDGE detection
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Fault Feature Extraction of Rotating Machinery Based on Wavelet Transformation and Multi-resolution Analysis
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作者 公茂法 刘庆雪 +1 位作者 刘明 张晓丽 《Journal of Measurement Science and Instrumentation》 CAS 2010年第4期312-314,共3页
这份报纸详细基于分离小浪转变和 multiresolution analysis.In 详细说明了精力光谱分析的原则特征抽取方法学习的方面,与在颤动信号并且就非平稳而言调查影响因素的特征并且颤动诊断信号非线性,有缺点的信号特征 description.Experi... 这份报纸详细基于分离小浪转变和 multiresolution analysis.In 详细说明了精力光谱分析的原则特征抽取方法学习的方面,与在颤动信号并且就非平稳而言调查影响因素的特征并且颤动诊断信号非线性,有缺点的信号特征 description.Experimental 结果的工具证明了这 method.To 的有效性是某 e 的 autbors 展开更多
关键词 故障特征提取 离散小波变换 多分辨率分析 旋转机械 多分辨分析 信号特征 影响因素 提取方法
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EEG epileptic seizure detection and classification based on dual-tree complex wavelet transform and machine learning algorithms 被引量:4
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作者 Itaf Ben Slimen Larbi Boubchir +1 位作者 Zouhair Mbarki Hassene Seddik 《The Journal of Biomedical Research》 CAS CSCD 2020年第3期151-161,共11页
The visual analysis of common neurological disorders such as epileptic seizures in electroencephalography(EEG) is an oversensitive operation and prone to errors,which has motivated the researchers to develop effective... The visual analysis of common neurological disorders such as epileptic seizures in electroencephalography(EEG) is an oversensitive operation and prone to errors,which has motivated the researchers to develop effective automated seizure detection methods.This paper proposes a robust automatic seizure detection method that can establish a veritable diagnosis of these diseases.The proposed method consists of three steps:(i) remove artifact from EEG data using Savitzky-Golay filter and multi-scale principal component analysis(MSPCA),(ii) extract features from EEG signals using signal decomposition representations based on empirical mode decomposition(EMD),discrete wavelet transform(DWT),and dual-tree complex wavelet transform(DTCWT) allowing to overcome the non-linearity and non-stationary of EEG signals,and(iii) allocate the feature vector to the relevant class(i.e.,seizure class "ictal" or free seizure class "interictal") using machine learning techniques such as support vector machine(SVM),k-nearest neighbor(k-NN),and linear discriminant analysis(LDA).The experimental results were based on two EEG datasets generated from the CHB-MIT database with and without overlapping process.The results obtained have shown the effectiveness of the proposed method that allows achieving a higher classification accuracy rate up to 100% and also outperforms similar state-of-the-art methods. 展开更多
关键词 ELECTROENCEPHALOGRAPHY epileptic seizure detection feature extraction dual-tree complex wavelet transform machine learning
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Single pixel imaging based on semi-continuous wavelet transform 被引量:1
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作者 高超 王晓茜 +4 位作者 王爽 苟立丹 冯玉玲 金光勇 姚治海 《Chinese Physics B》 SCIE EI CAS CSCD 2021年第7期244-252,共9页
Single pixel imaging is a novel imaging technique,and it becomes a focus of research in recent years due to its advantages such as high lateral resolution and high robustness to noise.Imaging speed is one of the criti... Single pixel imaging is a novel imaging technique,and it becomes a focus of research in recent years due to its advantages such as high lateral resolution and high robustness to noise.Imaging speed is one of the critical shortcomings,which limits the further development and applications of this technique.In this paper,we focus on the issues of imaging efficiency of a single pixel imaging system.We propose semi-continuous wavelet transform(SCWT)protocol and introduce the protocol into the single pixel imaging system.The proposed protocol is something between continuous wavelet transform and discrete wavelet transform,which allows the usage of those smooth(usually non-orthogonal,and they have advantages in representing smooth signals compressively,which can improve the imaging speed of single pixel imaging)wavelets and with limited numbers of measurements.The proposed imaging scheme is studied,and verified by simulations and experiments.Furthermore,a comparison between our proposed scheme and existing imaging schemes are given.According to the results,the proposed SCWT scheme is proved to be effective in reconstructing a image compressively. 展开更多
关键词 single pixel imaging wavelet transform modulation of light source
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Implementation of Texture Based Image Retrieval Using M-band Wavelet Transform
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作者 Liao Ya-li, Yang Yan, Cao Yang School of Electronic Information, Wuhan University, Wuhan 430072, Hubei, China 《Wuhan University Journal of Natural Sciences》 CAS 2003年第04A期1107-1110,共4页
Wavelet transform has attracted attention because it is a very useful tool for signal analyzing. As a fundamental characteristic of an image, texture traits play an important role in the human vision system for recogn... Wavelet transform has attracted attention because it is a very useful tool for signal analyzing. As a fundamental characteristic of an image, texture traits play an important role in the human vision system for recognition and interpretation of images. The paper presents an approach to implement texture-based image retrieval using M-band wavelet transform. Firstly the traditional 2-band wavelet is extended to M-band wavelet transform. Then the wavelet moments are computed by M-band wavelet coefficients in the wavelet domain. The set of wavelet moments forms the feature vector related to the texture distribution of each wavelet images. The distances between the feature vectors describe the similarities of different images. The experimental result shows that the M-band wavelet moment features of the images are effective for image indexing. The retrieval method has lower computational complexity, yet it is capable of giving better retrieval performance for a given medical image database. 展开更多
关键词 M-band wavelet transform wavelet moments feature vector image retrieval
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Biomedical Image Processing Using FCM Algorithm Based on the Wavelet Transform
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作者 闫玉华 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2004年第3期18-20,共3页
An effective processing method for biomedical images and the Fuzzy C-mean (FCM) algorithm based on the wavelet transform are investigated.By using hierarchical wavelet decomposition, an original image could be decompo... An effective processing method for biomedical images and the Fuzzy C-mean (FCM) algorithm based on the wavelet transform are investigated.By using hierarchical wavelet decomposition, an original image could be decomposed into one lower image and several detail images. The segmentation started at the lowest resolution with the FCM clustering algorithm and the texture feature extracted from various sub-bands. With the improvement of the FCM algorithm, FCM alternation frequency was decreased and the accuracy of segmentation was advanced. 展开更多
关键词 biomedical image processing FCM algorithm wavelet transform texture feature
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Investigation on the automatic parameters extraction of pulse signals based on wavelet transform 被引量:8
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作者 WANG Hui-yan ZHANG Pei-yong 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2007年第8期1283-1289,共7页
This paper analyses a key problem in the quantification of pulse diagnosis. Due to the subjectivity and fuzziness of pulse diagnosis,quantitative methods are needed. To extract the parameters of pulse signals,the prer... This paper analyses a key problem in the quantification of pulse diagnosis. Due to the subjectivity and fuzziness of pulse diagnosis,quantitative methods are needed. To extract the parameters of pulse signals,the prerequisite is to detect the corners of pulse signals correctly. Up to now,the pulse parameters are mostly acquired by marking the pulse corners manually,which is an obstacle to modernize pulse diagnosis. Therefore,a new automatic parameters extraction approach for pulse signals using wavelet transform is presented. The results testified that the method we proposed is feasible and effective and can detect corners of pulse signals accurately,which can be expected to facilitate the modernization of pulse diagnosis. 展开更多
关键词 脉冲信号 特征提取 小波变换 自动参数提取
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Generator Unit Fault Diagnosis Using the Frequency Slice Wavelet Transform Time-frequency Analysis Method 被引量:9
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作者 DUAN Chendong GAO Qiang XU Xianfeng 《中国电机工程学报》 EI CSCD 北大核心 2013年第32期I0014-I0014,16,共1页
为了提取有效的故障特征,提出了基于频率切片小波变换时频分解的故障特征分离提取方法。先对信号进行频率切片小波变换获取其时频分布,然后根据信号的能量分布特点选择时频区域,再以较高的时频分辨率对选择的时频区域进一步细化分析... 为了提取有效的故障特征,提出了基于频率切片小波变换时频分解的故障特征分离提取方法。先对信号进行频率切片小波变换获取其时频分布,然后根据信号的能量分布特点选择时频区域,再以较高的时频分辨率对选择的时频区域进一步细化分析,以突出隐含在信号中的时频特征,在此基础上分割出含有故障特征时频区域,再通过滤波和逆变换重构分离出有效的故障特征。仿真实验和工程应用表明,这种方法可从噪声信号中分离出有效的特征分量,在发电机组故障特征提取时取得了较好的效果。 展开更多
关键词 频率分析 小波变换 时频分析方法 故障诊断 发电机组 切片 振动信号 非平稳
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Walsh Hadamard Transform Based Transceiver Design for SC-FDMA with Discrete Wavelet Transform 被引量:2
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作者 Arsla Khan Amna Arif +1 位作者 Tabassum Nawaz Sobia Baig 《China Communications》 SCIE CSCD 2017年第5期193-206,共14页
This article proposes a new transceiver design for Single carrier frequency division multiple access(SCFDMA)system based on discrete wavelet transform(DWT). SCFDMA offers almost same structure as Orthogonal frequency ... This article proposes a new transceiver design for Single carrier frequency division multiple access(SCFDMA)system based on discrete wavelet transform(DWT). SCFDMA offers almost same structure as Orthogonal frequency division multiple access(OFDMA)with extra advantage of low Peak to Average Power Ratio(PAPR). Moreover,this article also suggests the application of Walsh Hadamard transform(WHT)for linear precoding(LP)to improve the PAPR performance of the system. Supremacy of the proposed transceiver over conventional Fast Fourier transform(FFT)based SCFDMA is shown through simulated results in terms of PAPR,spectral efficiency(SE)and bit error rate(BER). 展开更多
关键词 离散小波变换 收发器 哈达玛变换 正交频分多址接入 设计 HADAMARD变换 沃尔什 快速傅里叶变换
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Face Representation Using Combined Method of Gabor Filters, Wavelet Transformation and DCV and Recognition Using RBF
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作者 Kathirvalavakumar Thangairulappan Jebakumari Beulah Vasanthi Jeyasingh 《Journal of Intelligent Learning Systems and Applications》 2012年第4期266-273,共8页
An efficient face representation is a vital step for a successful face recognition system. Gabor features are known to be effective for face recognition. The Gabor features extracted by Gabor filters have large dimens... An efficient face representation is a vital step for a successful face recognition system. Gabor features are known to be effective for face recognition. The Gabor features extracted by Gabor filters have large dimensionality. The feature of wavelet transformation is feature reduction. Hence, the large dimensional Gabor features are reduced by wavelet transformation. The discriminative common vectors are obtained using the within-class scatter matrix method to get a feature representation of face images with enhanced discrimination and are classified using radial basis function network. The proposed system is validated using three face databases such as ORL, The Japanese Female Facial Expression (JAFFE) and Essex Face database. Experimental results show that the proposed method reduces the number of features, minimizes the computational complexity and yielded the better recognition rates. 展开更多
关键词 feature Extraction GABOR wavelet wavelet transformation Discriminative Common Vector RADIAL BASIS Function Neural Network
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A data-mining approach to biomarker identification from protein profiles using discrete stationary wavelet transform
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作者 Hussain MONTAZERY-KORDY Mohammad Hossein MIRAN-BAYGI Mohammad Hassan MORADI 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2008年第11期863-870,共8页
Objective: To develop a new bioinformatic tool based on a data-mining approach for extraction of the most infor- mative proteins that could be used to find the potential biomarkers for the detection of cancer. Methods... Objective: To develop a new bioinformatic tool based on a data-mining approach for extraction of the most infor- mative proteins that could be used to find the potential biomarkers for the detection of cancer. Methods: Two independent datasets from serum samples of 253 ovarian cancer and 167 breast cancer patients were used. The samples were examined by surface- enhanced laser desorption/ionization time-of-flight mass spectrometry (SELDI-TOF MS). The datasets were used to extract the informative proteins using a data-mining method in the discrete stationary wavelet transform domain. As a dimensionality re- duction procedure, the hard thresholding method was applied to reduce the number of wavelet coefficients. Also, a distance measure was used to select the most discriminative coefficients. To find the potential biomarkers using the selected wavelet coefficients, we applied the inverse discrete stationary wavelet transform combined with a two-sided t-test. Results: From the ovarian cancer dataset, a set of five proteins were detected as potential biomarkers that could be used to identify the cancer patients from the healthy cases with accuracy, sensitivity, and specificity of 100%. Also, from the breast cancer dataset, a set of eight proteins were found as the potential biomarkers that could separate the healthy cases from the cancer patients with accuracy of 98.26%, sensitivity of 100%, and specificity of 95.6%. Conclusion: The results have shown that the new bioinformatic tool can be used in combination with the high-throughput proteomic data such as SELDI-TOF MS to find the potential biomarkers with high discriminative power. 展开更多
关键词 癌症 分类方法 特征筛选 诊断方法
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Application of wavelet transform in feature extraction and pattern recognition of wideband echoes 被引量:8
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作者 ZHAO Jianping HUANG Jianguo ZHANG Huafeng(College of Marine Engineering, Northwestern Polytechnical University Xi’an 710072) 《Chinese Journal of Acoustics》 1998年第3期213-220,共8页
A novel approach to extract edge features from wideband echo is proposed. The set of extracted features not only represents the echo waveform in a concise way, but also is sufficient and well suited for classification... A novel approach to extract edge features from wideband echo is proposed. The set of extracted features not only represents the echo waveform in a concise way, but also is sufficient and well suited for classification of non-stationary echo data from objects with different property.The feature extraction is derived from the Discrete Dyadic Wavlet Transform (DDWT) of the echo through the undecimated algorithm. The motivation we use the DDWT is that it is time-shift-invariant which is beneficial for localization of edge, and the wavelet coefficients at larger scale represent the main shape feature of echo, i.e. edge, and the noise and modulated high-frequency components are reduced with scale increased. Some experimental results using real data which contain 144 samples from 4 classes of lake bottoms with different sediments are provided. The results show that our approach is a prospective way to represent wideband echo for reliable recognition of nonstationary echo with great variability. 展开更多
关键词 MALLAT IEEE SP Application of wavelet transform in feature extraction and pattern recognition of wideband echoes
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