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Mapping winter wheat using phenological feature of peak before winter on the North China Plain based on time-series MODIS data 被引量:17
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作者 TAO Jian-bin WU Wen-bin +2 位作者 ZHOU Yong WANG Yu JIANG Yan 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2017年第2期348-359,共12页
By employing the unique phenological feature of winter wheat extracted from peak before winter (PBW) and the advantages of moderate resolution imaging spectroradiometer (MODIS) data with high temporal resolution a... By employing the unique phenological feature of winter wheat extracted from peak before winter (PBW) and the advantages of moderate resolution imaging spectroradiometer (MODIS) data with high temporal resolution and intermediate spatial resolution, a remote sensing-based model for mapping winter wheat on the North China Plain was built through integration with Landsat images and land-use data. First, a phenological window, PBW was drawn from time-series MODIS data. Next, feature extraction was performed for the PBW to reduce feature dimension and enhance its information. Finally, a regression model was built to model the relationship of the phenological feature and the sample data. The amount of information of the PBW was evaluated and compared with that of the main peak (MP). The relative precision of the mapping reached up to 92% in comparison to the Landsat sample data, and ranged between 87 and 96% in comparison to the statistical data. These results were sufficient to satisfy the accuracy requirements for winter wheat mapping at a large scale. Moreover, the proposed method has the ability to obtain the distribution information for winter wheat in an earlier period than previous studies. This study could throw light on the monitoring of winter wheat in China by using unique phenological feature of winter wheat. 展开更多
关键词 time-series MODIS data phenological feature peak before wintering winter wheat mapping
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Researches on Classification Features of Rural and Urban Domestic Waste in Tianjin City Under Secondary Classification Mode
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作者 梁海恬 高贤彪 +5 位作者 何宗均 李妍 吴迪 王德芳 钱姗 李玉华 《Agricultural Science & Technology》 CAS 2015年第12期2854-2858,共5页
In order to investigate the influence of secondary classification mode on waste generation features, this study classified domestic waste generated by 310 rural and urban households at urban areas and Shuigaozhuang Vi... In order to investigate the influence of secondary classification mode on waste generation features, this study classified domestic waste generated by 310 rural and urban households at urban areas and Shuigaozhuang Village of Xiqing District into 3 groups: compostable materials, recyclable materials and toxics on the basis of the constructed secondary classification mode of domestic waste. The study focused on waste generation strength and classification features, compared the waste generation features between rural and urban residents, and analyzed the re- lation between waste generation strength and economic and cultural factors. The re- sults indicated that the average generation speed of urban domestic waste was 423.08 g/(d.capita), and that of rural domestic waste was 629.89 g/(d.capita), there was significant difference between rural and urban compost generation strength (P= 0.00002), while the generation strength of recyclable materials and toxics between rural and urban areas had no significant difference (P=0.471 and P=0.099, respec- tively). Secondary classification mode is an effective source classification mode for domestic wastes and has positive effects on waste reduction and treatment. 展开更多
关键词 Secondary classification mode Domestic waste Compostable materials Classification features Generation strength
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Geological Features and Reservoiring Mode of Shale Gas Reservoirs in Longmaxi Formation of the Jiaoshiba Area 被引量:30
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作者 GUO Xusheng HU Dongfeng +2 位作者 LI Yuping LIU Ruobing WANG Qingbo 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2014年第6期1811-1821,共11页
This study is based on the sedimentation conditions, organic geochemistry, storage spaces, physical properties, lithology and gas content of the shale gas reservoirs in Longmaxi Formation of the Jiaoshiba area and the... This study is based on the sedimentation conditions, organic geochemistry, storage spaces, physical properties, lithology and gas content of the shale gas reservoirs in Longmaxi Formation of the Jiaoshiba area and the gas accumulation mode is summarized and then compared with that in northern America. The shale gas reservoirs in the Longmaxi Formation in Jiaoshiba have good geological conditions, great thickness of quality shales, high organic content, high gas content, good physical properties, suitable depth, good preservation conditions and good reservoir types. The quality shales at the bottom of the deep shelf are the main target interval for shale gas exploration and development. Shale gas in the Longmaxi Formation has undergone three main reservoiring stages:the early stage of hydrocarbon generation and compaction when shale gas reservoirs were first formed; the middle stage of deep burial and large-scale hydrocarbon generation, which caused the enrichment of reservoirs with shale gas; the late stage of uplift, erosion and fracture development when shale gas reservoirs were finally formed. 展开更多
关键词 reservoiring mode shale gas Jiaoshiba area gas reservoir features Longmaxi Formation Sichuan Basin
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Fault Diagnosis Model Based on Feature Compression with Orthogonal Locality Preserving Projection 被引量:14
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作者 TANG Baoping LI Feng QIN Yi 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2011年第5期891-898,共8页
Based on feature compression with orthogonal locality preserving projection(OLPP),a novel fault diagnosis model is proposed in this paper to achieve automation and high-precision of fault diagnosis of rotating machi... Based on feature compression with orthogonal locality preserving projection(OLPP),a novel fault diagnosis model is proposed in this paper to achieve automation and high-precision of fault diagnosis of rotating machinery.With this model,the original vibration signals of training and test samples are first decomposed through the empirical mode decomposition(EMD),and Shannon entropy is constructed to achieve high-dimensional eigenvectors.In order to replace the traditional feature extraction way which does the selection manually,OLPP is introduced to automatically compress the high-dimensional eigenvectors of training and test samples into the low-dimensional eigenvectors which have better discrimination.After that,the low-dimensional eigenvectors of training samples are input into Morlet wavelet support vector machine(MWSVM) and a trained MWSVM is obtained.Finally,the low-dimensional eigenvectors of test samples are input into the trained MWSVM to carry out fault diagnosis.To evaluate our proposed model,the experiment of fault diagnosis of deep groove ball bearings is made,and the experiment results indicate that the recognition accuracy rate of the proposed diagnosis model for outer race crack、inner race crack and ball crack is more than 90%.Compared to the existing approaches,the proposed diagnosis model combines the strengths of EMD in fault feature extraction,OLPP in feature compression and MWSVM in pattern recognition,and realizes the automation and high-precision of fault diagnosis. 展开更多
关键词 orthogonal locality preserving projection(OLPP) manifold learning feature compression Morlet wavelet support vector machine(MWSVM) empirical mode decomposition(EMD) fault diagnosis
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Arrhythmia Prediction on Optimal Features Obtained from the ECG as Images
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作者 Fuad A.M.Al-Yarimi 《Computer Systems Science & Engineering》 SCIE EI 2023年第1期129-142,共14页
A critical component of dealing with heart disease is real-time identifi-cation,which triggers rapid action.The main challenge of real-time identification is illustrated here by the rare occurrence of cardiac arrhythm... A critical component of dealing with heart disease is real-time identifi-cation,which triggers rapid action.The main challenge of real-time identification is illustrated here by the rare occurrence of cardiac arrhythmias.Recent contribu-tions to cardiac arrhythmia prediction using supervised learning approaches gen-erally involve the use of demographic features(electronic health records),signal features(electrocardiogram features as signals),and temporal features.Since the signal of the electrical activity of the heartbeat is very sensitive to differences between high and low heartbeats,it is possible to detect some of the irregularities in the early stages of arrhythmia.This paper describes the training of supervised learning using features obtained from electrocardiogram(ECG)image to correct the limitations of arrhythmia prediction by using demographic and electrocardio-graphic signal features.An experimental study demonstrates the usefulness of the proposed Arrhythmia Prediction by Supervised Learning(APSL)method,whose features are obtained from the image formats of the electrocardiograms used as input. 展开更多
关键词 ECG records ELECTROCARDIOGRAM morphological features(MF) empirical mode decomposition algorithm HOS
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A bearing fault feature extraction method based on cepstrum pre-whitening and a quantitative law of symplectic geometry mode decomposition 被引量:1
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作者 Chen Yiya Jia Minping Yan Xiaoan 《Journal of Southeast University(English Edition)》 EI CAS 2021年第1期33-41,共9页
In order to extract the fault feature of the bearing effectively and prevent the impact components caused by bearing damage being interfered with by discrete frequency components and background noise,a method of fault... In order to extract the fault feature of the bearing effectively and prevent the impact components caused by bearing damage being interfered with by discrete frequency components and background noise,a method of fault feature extraction based on cepstrum pre-whitening(CPW)and a quantitative law of symplectic geometry mode decomposition(SGMD)is proposed.First,CPW is performed on the original signal to enhance the impact feature of bearing fault and remove the periodic frequency components from complex vibration signals.The pre-whitening signal contains only background noise and non-stationary shock caused by damage.Secondly,a quantitative law that the number of effective eigenvalues of the Hamilton matrix is twice the number of frequency components in the signal during SGMD is found,and the quantitative law is verified by simulation and theoretical derivation.Finally,the trajectory matrix of the pre-whitening signal is constructed and SGMD is performed.According to the quantitative law,the corresponding feature vector is selected to reconstruct the signal.The Hilbert envelope spectrum analysis is performed to extract fault features.Simulation analysis and application examples prove that the proposed method can clearly extract the fault feature of bearings. 展开更多
关键词 cepstrum pre-whitening symplectic geometry mode decomposition EIGENVALUE quantitative law feature extraction
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Research on Feature Extraction and Classification Method of Vibration Signal of Escalator Sprocket Bearing
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作者 Deyang Liu Yuhang Su +2 位作者 Ningxiang Yang Jianxun Chen Jicheng Li 《电气工程与自动化(中英文版)》 2023年第1期1-10,共10页
In order to improve the accuracy of escalator sprocket bearing fault diagnosis,the problem of the feature extraction method of bearing vibration signal is addressed.In this paper,empirical mode is used to decompose th... In order to improve the accuracy of escalator sprocket bearing fault diagnosis,the problem of the feature extraction method of bearing vibration signal is addressed.In this paper,empirical mode is used to decompose the original signal,and the optimal modal component among the multiple modal components is obtained after the optimization decomposition is selected by the envelope spectrum method,and the multi-angle feature measure is introduced to extract the fault characteristic value.According to the vibration characteristics of the bearing vibration signal data,a bearing signal feature group that is more inclined to the fault feature category information is established,which avoids the absolute problem of extracting a single metric feature.The fuzzy C-means clustering algorithm is used to cluster the sample data with similar characteristics into the same cluster area,which effectively solves the problem that a single measurement analysis cannot characterize the complex internal characteristics ofthe bearing vibration signal. 展开更多
关键词 BEARING VIBRATION Multi-Angle feature Measurement Signal feature Group Empirical mode Fuzzy C-Means Clustering
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Feature Layer Fusion of Linear Features and Empirical Mode Decomposition of Human EMG Signal
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作者 Jun-Yao Wang Yue-Hong Dai Xia-Xi Si 《Journal of Electronic Science and Technology》 CAS CSCD 2022年第3期257-269,共13页
To explore the influence of the fusion of different features on recognition,this paper took the electromyography(EMG)signals of rectus femoris under different motions(walk,step,ramp,squat,and sitting)as samples,linear... To explore the influence of the fusion of different features on recognition,this paper took the electromyography(EMG)signals of rectus femoris under different motions(walk,step,ramp,squat,and sitting)as samples,linear features(time-domain features(variance(VAR)and root mean square(RMS)),frequency-domain features(mean frequency(MF)and mean power frequency(MPF)),and nonlinear features(empirical mode decomposition(EMD))of the samples were extracted.Two feature fusion algorithms,the series splicing method and complex vector method,were designed,which were verified by a double hidden layer(BP)error back propagation neural network.Results show that with the increase of the types and complexity of feature fusions,the recognition rate of the EMG signal to actions is gradually improved.When the EMG signal is used in the series splicing method,the recognition rate of time-domain+frequency-domain+empirical mode decomposition(TD+FD+EMD)splicing is the highest,and the average recognition rate is 92.32%.And this rate is raised to 96.1%by using the complex vector method,and the variance of the BP system is also reduced. 展开更多
关键词 Complex vector method electromyography(EMG)signal empirical mode decomposition feature layer fusion series splicing method
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A SEMI-OPEN-LOOP CODING MODE SELECTION ALGORITHM BASED ON EFM AND SELECTED AMR-WB+ FEATURES
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作者 Hong Ying Zhao Shenghui Kuang Jingming 《Journal of Electronics(China)》 2009年第2期274-278,共5页
To solve the problems of the AMR-WB+(Extended Adaptive Multi-Rate-WideBand) semi-open-loop coding mode selection algorithm,features for ACELP(Algebraic Code Excited Linear Prediction) and TCX(Transform Coded eXcitatio... To solve the problems of the AMR-WB+(Extended Adaptive Multi-Rate-WideBand) semi-open-loop coding mode selection algorithm,features for ACELP(Algebraic Code Excited Linear Prediction) and TCX(Transform Coded eXcitation) classification are investigated.11 classifying features in the AMR-WB+ codec are selected and 2 novel classifying features,i.e.,EFM(Energy Flatness Measurement) and stdEFM(standard deviation of EFM),are proposed.Consequently,a novel semi-open-loop mode selection algorithm based on EFM and selected AMR-WB+ features is proposed.The results of classifying test and listening test show that the performance of the novel algorithm is much better than that of the AMR-WB+ semi-open-loop coding mode selection algorithm. 展开更多
关键词 Speech/Audio Semi-open-loop coding mode selection features selection Energy Flat-ness Measurement(EFM)
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APPLICATION OF IMPROVED EMD IN VIBRATION SIGNAL FEATURE EXTRACTION OF VEHICLE
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作者 辛江慧 安木金 +1 位作者 张雨 任成龙 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2012年第2期193-198,共6页
In order to truly obtain the feature extraction of vibration signals under the strong background noise, the analysis and improvement of empirical mode decomposition (EMD) is carried on. After that, the improved EMD ... In order to truly obtain the feature extraction of vibration signals under the strong background noise, the analysis and improvement of empirical mode decomposition (EMD) is carried on. After that, the improved EMD is applied to the feature extraction of vehicle vibration signals. First, the multi-autocorrelation method is adopted in each input signal,so the noise is reduced effectively. Then, EMD is used to deal with these signals,and the intrinsic mode functions (IMFs) are obtained. Finally, for obtaining the feature information of these signals, the Hilbert transformation and the spectrum analysis are performed in some IMFs. Theoretical analysis and ex- periment verify the effectiveness of the method, which are valuable reference for the same engineering problems. 展开更多
关键词 empirical mode decomposition (EMD) vehicle vibration signal multi-autocorrelation feature ex- traction
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Feature deformation network with multi-range feature enhancement for agricultural machinery operation mode identification
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作者 Weixin Zhai Zhi Xu +5 位作者 Jinming Liu Xiya Xiong Jiawen Pan Sun-Ok Chung Dionysis Bochtis Caicong Wu 《International Journal of Agricultural and Biological Engineering》 SCIE 2024年第4期265-275,共11页
Utilizing the spatiotemporal features contained in extensive trajectory data for identifying operation modes of agricultural machinery is an important basis task for subsequent agricultural machinery trajectory resear... Utilizing the spatiotemporal features contained in extensive trajectory data for identifying operation modes of agricultural machinery is an important basis task for subsequent agricultural machinery trajectory research.In the present study,to effectively identify agricultural machinery operation mode,a feature deformation network with multi-range feature enhancement was proposed.First,a multi-range feature enhancement module was developed to fully explore the feature distribution of agricultural machinery trajectory data.Second,to further enrich the representation of trajectories,a feature deformation module was proposed that can map trajectory points to high-dimensional space to form feature maps.Then,EfficientNet-B0 was used to extract features of different scales and depths from the feature map,select features highly relevant to the results,and finally accurately predict the mode of each trajectory point.To validate the effectiveness of the proposed method,experiments were conducted to compare the results with those of other methods on a dataset of real agricultural trajectories.On the corn and wheat harvester trajectory datasets,the model achieved accuracies of 96.88%and 96.68%,as well as F1 scores of 93.54%and 94.19%,exhibiting improvements of 8.35%and 9.08%in accuracy and 20.99%and 20.04%in F1 score compared with the current state-of-the-art method. 展开更多
关键词 road-field trajectory classification efficientNet feature deformation network multi-range feature enhancement agricultural machinery operation mode recognition
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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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A novel feature extraction method for ship-radiated noise 被引量:4
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作者 Hong Yang Lu-lu Li +1 位作者 Guo-hui Li Qian-ru Guan 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2022年第4期604-617,共14页
To improve the feature extraction of ship-radiated noise in a complex ocean environment,a novel feature extraction method for ship-radiated noise based on complete ensemble empirical mode decomposition with adaptive s... To improve the feature extraction of ship-radiated noise in a complex ocean environment,a novel feature extraction method for ship-radiated noise based on complete ensemble empirical mode decomposition with adaptive selective noise(CEEMDASN) and refined composite multiscale fluctuation-based dispersion entropy(RCMFDE) is proposed.CEEMDASN is proposed in this paper which takes into account the high frequency intermittent components when decomposing the signal.In addition,RCMFDE is also proposed in this paper which refines the preprocessing process of the original signal based on composite multi-scale theory.Firstly,the original signal is decomposed into several intrinsic mode functions(IMFs)by CEEMDASN.Energy distribution ratio(EDR) and average energy distribution ratio(AEDR) of all IMF components are calculated.Then,the IMF with the minimum difference between EDR and AEDR(MEDR)is selected as characteristic IMF.The RCMFDE of characteristic IMF is estimated as the feature vectors of ship-radiated noise.Finally,these feature vectors are sent to self-organizing map(SOM) for classifying and identifying.The proposed method is applied to the feature extraction of ship-radiated noise.The result shows its effectiveness and universality. 展开更多
关键词 Complete ensemble empirical mode decomposition with adaptive noise Ship-radiated noise feature extraction Classification and recognition
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The geological heritages in Xinjiang, China: Its features and protection 被引量:1
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作者 HUANG Song 《Journal of Geographical Sciences》 SCIE CSCD 2010年第3期357-374,共18页
The geological heritage protection and its development at home and abroad reflect the progress in the aspect from the single protection to the coordination between protection and exploitation. The geopark established ... The geological heritage protection and its development at home and abroad reflect the progress in the aspect from the single protection to the coordination between protection and exploitation. The geopark established by UNESCO has closely combined the protection of geological heritages with the promotion of sustainable development of local economy, which has become the best way to protect geological heritages. The geological heritages in Xinjiang, China, are characterized by their large quantity, rich variety and high grade. The complicated geologic-geomorphic environment in Xinjiang contributes to the creation of various geological heritage types and their spatial distribution, and at the same time makes them under control. The main types of the geological heritages in Xinjiang are the geologic-geomorphic landscapes and the water landscapes. The spatial distribution can be divided into five geological heritage districts: Altay, Junggar, Tianshan, Tarim and Kunlun-Altun, among which Tianshan and Kunlun-Altun are most important. Based on the first systematic investigation of the geological heritages in Xinjiang, it is confirmed that the insufficient coordination between protection and exploitation is the primary cause for the backward situation in the geological heritage protection. To solve the problem, this paper proposes 6 major protection steps--from determining the protection types, the protection forms, the protection modes, the protection grades, the protection sequences to determining the' protection zones, brings forward the idea of optimal-selection which integrates geoparks with geological heritage protection areas and other protection areas as protection and exploitation reserve list for 209 well as 5 corresponding modes, and makes a important geological heritages in Xinjiang. 展开更多
关键词 geological heritages featureS situation analysis protection steps optimal-selection modes reserve list XINJIANG
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Vibration-based feature extraction of determining dynamic characteristic for engine block low vibration design 被引量:2
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作者 杜宪峰 李志军 +3 位作者 毕凤荣 张俊红 王霞 邵康 《Journal of Central South University》 SCIE EI CAS 2012年第8期2238-2246,共9页
In order to maintain vibration performances within the limits of the design, a vibration-based feature extraction method for dynamic characteristic using empirical mode decomposition (EMD) and wavelet analysis was p... In order to maintain vibration performances within the limits of the design, a vibration-based feature extraction method for dynamic characteristic using empirical mode decomposition (EMD) and wavelet analysis was proposed. The proposed method was verified experimentally and numerically by implementing the scheme on engine block. In the implementation process, the following steps were identified to be important: 1) EMD technique in order to solve the feature extraction of vibration signals; 2) Vibration measurement for the purpose of confirming the structural weak regions of engine block in experiment; 3) Finite element modeling for the purpose of determining dynamic characteristic in time region and frequency region to affirm the comparability of response character corresponding to improvement schemes; 4) Adopting a feature index oflMF for structural improvement based on EMD and wavelet analysis. The obtained results show that IMF of signal is more sensitive to response character corresponding to improvement schemes. Finally, examination of the results confirms that the proposed vibration-based feature extraction method is very robust, and focuses on the relative merits of modification and full-scale structural optimization of engine, together with the creation of new low-vibration designs. 展开更多
关键词 feature extraction dynamic characteristic finite element model empirical mode decomposition diesel engine block
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A fault feature extraction method of gearbox based on compound dictionary noise reduction and optimized Fourier decomposition 被引量:1
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作者 Mao Yifan Xu Feiyun 《Journal of Southeast University(English Edition)》 EI CAS 2021年第1期22-32,共11页
Aimed at the problem that Fourier decomposition method(FDM)is sensitive to noise and existing mode mixing cannot accurately extract gearbox fault features,a gear fault feature extraction method combining compound dict... Aimed at the problem that Fourier decomposition method(FDM)is sensitive to noise and existing mode mixing cannot accurately extract gearbox fault features,a gear fault feature extraction method combining compound dictionary noise reduction and optimized FDM(OFDM)is proposed.Firstly,the characteristics of the gear signals are used to construct a compound dictionary,and the orthogonal matching pursuit algorithm(OMP)is combined to reduce the noise of the vibration signal.Secondly,in order to overcome the mode mixing phenomenon occuring during the decomposition of FDM,a method of frequency band division based on the extremum of the spectrum is proposed to optimize the decomposition quality.Then,the OFDM is used to decompose the signal into several analytic Fourier intrinsic band functions(AFIBFs).Finally,the AFIBF with the largest correlation coefficient is selected for Hilbert envelope spectrum analysis.The fault feature frequencies of the vibration signal can be accurately extracted.The proposed method is validated through analyzing the gearbox fault simulation signal and the real vibration signals collected from an experimental gearbox. 展开更多
关键词 Fourier decomposition compound dictionary mode mixing gearbox fault feature extraction
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Authentication based on feature of hand-written signature 被引量:1
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作者 朱树人 《Journal of Central South University of Technology》 EI 2007年第4期563-567,共5页
The typical features of the coordinate and the curvature as well as the recorded time information were analyzed in the hand-written signatures.In the hand-written signature process 10 biometric features were summarize... The typical features of the coordinate and the curvature as well as the recorded time information were analyzed in the hand-written signatures.In the hand-written signature process 10 biometric features were summarized:the amount of zero speed in direction x and direction y,the amount of zero acceleration in direction x and direction y,the total time of the hand-written signatures,the total distance of the pen traveling in the hand-written process,the frequency for lifting the pen,the time for lifting the pen,the amount of the pressure higher or lower than the threshold values.The formulae of biometric features extraction were summarized.The Gauss function was used to draw the typical information from the above-mentioned biometric features,with which to establish the hidden Markov mode and to train it.The frame of double authentication was proposed by combing the signature with the digital signature.Web service technology was applied in the system to ensure the security of data transmission.The training practice indicates that the hand-written signature verification can satisfy the needs from the office automation systems. 展开更多
关键词 behavioral biostatistics feature hand-written signature hidden Markov mode signature verification
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Radiographic Features of Osteogenesis Imperfecta about a Female Sibship
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作者 B. M. A. Tiemtore-Kambou A. M. Napon +5 位作者 N.-A. Ndé-Ouédraogo A. Koutou I. F. N. Sieba I. Ouédraogo O. Diallo R. Cissé 《Open Journal of Medical Imaging》 2020年第1期52-61,共10页
Osteogenesis imperfecta (OI) belongs to a group of congenital osteoporosis which hallmark feature is “affecting skeleton, increasing bone fragility that fracture easily and decreasing bone density due to quantitative... Osteogenesis imperfecta (OI) belongs to a group of congenital osteoporosis which hallmark feature is “affecting skeleton, increasing bone fragility that fracture easily and decreasing bone density due to quantitative and/or qualita-tive abnormalities”. We report a female sibling’s involvement in 3 cases with probable recessive inheritance pattern. Only female aged between 5 and 13 years were affected with skeletal lesions in the lower limbs. The boy of this family had no skeletal or extra-skeletal lesions. Their parents had no affection and no bond of consanguinity. The observed malformations can be classified as type V or VI according to Sillence’s clinical classification. Lack of genetic test in our context has limited accuracy of the diagnosis as new data evoke a genetic classification into 12 types that leading an effective therapeutic management. 展开更多
关键词 OSTEOGENESIS Imperfecta FAMILIAL INVOLVEMENT FEMALE RADIOLOGICAL features RECESSIVE mode
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MOLECULAR DYNAMICS SIMULATION ON VIERATIONAL SPECTROSCOPIC FEATURES OF HYDROGEN BONDS IN CRYSTALLINE POLYMERS
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作者 Xiao Zhen YANG Shaw Ling HSU Polymer Physics Laboratory Institute of Chemistry, Academia Sinica, Beijing 100080 Materials Research Laboratory University of Massachusetts Amherst, MA 01003 USA 《Chinese Chemical Letters》 SCIE CAS CSCD 1993年第7期635-638,共4页
Introduction The molecular dynamics simulation technique has recently proved to be a suitable alternative approachfor simulation of vibrational spectroscopy. In this study, molecular dynamics was utilized to understan... Introduction The molecular dynamics simulation technique has recently proved to be a suitable alternative approachfor simulation of vibrational spectroscopy. In this study, molecular dynamics was utilized to understandlow frequency vibrations in highly ordered poly(ρ-phenylene terephthalmide) (PPTA). A key structuralfeature of this polymer is the presence of hydrogen bonds. There is little question that this strong localized 展开更多
关键词 mode MOLECULAR DYNAMICS SIMULATION ON VIERATIONAL SPECTROSCOPIC featureS OF HYDROGEN BONDS IN CRYSTALLINE POLYMERS
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Market Features in 2008
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作者 Wang Ting 《China Textile》 2009年第2期44-49,共6页
Luxury Brands Enter 2nd Tier Cities Event: In October 2008, a new LV franchised store was launched in MASION MODE in Urumchi in Xinjiang Province, which is the
关键词 MORE mode Market features in 2008
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