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Remote Sensing Image Retrieval Based on 3D-Local Ternary Pattern(LTP)Features and Non-subsampled Shearlet Transform(NSST)Domain Statistical Features
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作者 Hilly Gohain Baruah Vijay Kumar Nath Deepika Hazarika 《Computer Modeling in Engineering & Sciences》 SCIE EI 2022年第4期137-164,共28页
With the increasing popularity of high-resolution remote sensing images,the remote sensing image retrieval(RSIR)has always been a topic of major issue.A combined,global non-subsampled shearlet transform(NSST)-domain s... With the increasing popularity of high-resolution remote sensing images,the remote sensing image retrieval(RSIR)has always been a topic of major issue.A combined,global non-subsampled shearlet transform(NSST)-domain statistical features(NSSTds)and local three dimensional local ternary pattern(3D-LTP)features,is proposed for high-resolution remote sensing images.We model the NSST image coefficients of detail subbands using 2-state laplacian mixture(LM)distribution and its three parameters are estimated using Expectation-Maximization(EM)algorithm.We also calculate the statistical parameters such as subband kurtosis and skewness from detail subbands along with mean and standard deviation calculated from approximation subband,and concatenate all of them with the 2-state LM parameters to describe the global features of the image.The various properties of NSST such as multiscale,localization and flexible directional sensitivity make it a suitable choice to provide an effective approximation of an image.In order to extract the dense local features,a new 3D-LTP is proposed where dimension reduction is performed via selection of‘uniform’patterns.The 3D-LTP is calculated from spatial RGB planes of the input image.The proposed inter-channel 3D-LTP not only exploits the local texture information but the color information is captured too.Finally,a fused feature representation(NSSTds-3DLTP)is proposed using new global(NSSTds)and local(3D-LTP)features to enhance the discriminativeness of features.The retrieval performance of proposed NSSTds-3DLTP features are tested on three challenging remote sensing image datasets such as WHU-RS19,Aerial Image Dataset(AID)and PatternNet in terms of mean average precision(MAP),average normalized modified retrieval rank(ANMRR)and precision-recall(P-R)graph.The experimental results are encouraging and the NSSTds-3DLTP features leads to superior retrieval performance compared to many well known existing descriptors such as Gabor RGB,Granulometry,local binary pattern(LBP),Fisher vector(FV),vector of locally aggregated descriptors(VLAD)and median robust extended local binary pattern(MRELBP).For WHU-RS19 dataset,in terms of{MAP,ANMRR},the NSSTds-3DLTP improves upon Gabor RGB,Granulometry,LBP,FV,VLAD and MRELBP descriptors by{41.93%,20.87%},{92.30%,32.68%},{86.14%,31.97%},{18.18%,15.22%},{8.96%,19.60%}and{15.60%,13.26%},respectively.For AID,in terms of{MAP,ANMRR},the NSSTds-3DLTP improves upon Gabor RGB,Granulometry,LBP,FV,VLAD and MRELBP descriptors by{152.60%,22.06%},{226.65%,25.08%},{185.03%,23.33%},{80.06%,12.16%},{50.58%,10.49%}and{62.34%,3.24%},respectively.For PatternNet,the NSSTds-3DLTP respectively improves upon Gabor RGB,Granulometry,LBP,FV,VLAD and MRELBP descriptors by{32.79%,10.34%},{141.30%,24.72%},{17.47%,10.34%},{83.20%,19.07%},{21.56%,3.60%},and{19.30%,0.48%}in terms of{MAP,ANMRR}.The moderate dimensionality of simple NSSTds-3DLTP allows the system to run in real-time. 展开更多
关键词 Remote sensing image retrieval laplacian mixture model local ternary pattern statistical modeling KS test texture global features
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Failure evolution and disaster prediction of rock under uniaxial compression based on non-extensive statistical analysis of electric potential
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作者 Tiancheng Shan Zhonghui Li +7 位作者 Haishan Jia Enyuan Wang Xiaoran Wang Yue Niu Xin Zhang Dong Chen Shan Yin Quancong Zhang 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2024年第7期975-993,共19页
Rock failure can cause serious geological disasters,and the non-extensive statistical features of electric potential(EP)are expected to provide valuable information for disaster prediction.In this paper,the uniaxial c... Rock failure can cause serious geological disasters,and the non-extensive statistical features of electric potential(EP)are expected to provide valuable information for disaster prediction.In this paper,the uniaxial compression experiments with EP monitoring were carried out on fine sandstone,marble and granite samples under four displacement rates.The Tsallis entropy q value of EPs is used to analyze the selforganization evolution of rock failure.Then the influence of displacement rate and rock type on q value are explored by mineral structure and fracture modes.A self-organized critical prediction method with q value is proposed.The results show that the probability density function(PDF)of EPs follows the q-Gaussian distribution.The displacement rate is positively correlated with q value.With the displacement rate increasing,the fracture mode changes,the damage degree intensifies,and the microcrack network becomes denser.The influence of rock type on q value is related to the burst intensity of energy release and the crack fracture mode.The q value of EPs can be used as an effective prediction index for rock failure like b value of acoustic emission(AE).The results provide useful reference and method for the monitoring and early warning of geological disasters. 展开更多
关键词 Electric potential Non-extensive statistical feature Displacement rate q-Gaussian distribution Precursor prediction Rock materials
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Anomaly traffic detection of database network based on flow statistical features
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作者 Xinliang WANG Fang LIU +1 位作者 Luying CHEN Zhenming LEI 《Frontiers of Electrical and Electronic Engineering in China》 CSCD 2010年第1期85-90,共6页
The traditional intrusion detection system has the problem of high false positive rate and false negative rate.This paper deeply analyzes the differences of statistical features between single-flow and multi-flow on t... The traditional intrusion detection system has the problem of high false positive rate and false negative rate.This paper deeply analyzes the differences of statistical features between single-flow and multi-flow on the database network,and presents a group of features that are easy to acquire and can be used to detect the anomaly in database network efficiently.By applying this group of features in Fisher algorithm for anomaly detection,the false positive rate and false negative rate are dramatically reduced.Simultaneously,the model made by using the group of features has the advantages of low algorithm complexity,good detection result and strong generalization ability.Experimental results show that there is higher accuracy when using the features of single-flow and multiflow to construct the anomaly detection model than only using single-flow features. 展开更多
关键词 anomaly detection FLOW statistical feature FISHER statistical package for social sciences(SPSS)
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Classifying Machine Learning Features Extracted from Vibration Signal with Logistic Model Tree to Monitor Automobile Tyre Pressure 被引量:1
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作者 P.S.Anoop V.Sugumaran 《Structural Durability & Health Monitoring》 EI 2017年第2期191-208,共18页
Tyre pressure monitoring system(TPMS)is compulsory in most countries like the United States and European Union.The existing systems depend on pressure sensors strapped on the tyre or on wheel speed sensor data.A diffe... Tyre pressure monitoring system(TPMS)is compulsory in most countries like the United States and European Union.The existing systems depend on pressure sensors strapped on the tyre or on wheel speed sensor data.A difference in wheel speed would trigger an alarm based on the algorithm implemented.In this paper,machine learning approach is proposed as a new method to monitor tyre pressure by extracting the vertical vibrations from a wheel hub of a moving vehicle using an accelerometer.The obtained signals will be used to compute through statistical features and histogram features for the feature extraction process.The LMT(Logistic Model Tree)was used as the classifier and attained a classification accuracy of 92.5%with 10-fold cross validation for statistical features and 90.5% with 10-fold cross validation for histogram features.The proposed model can be used for monitoring the automobile tyre pressure successfully. 展开更多
关键词 Machine learning Vibration ACCELEROMETER statistical features Histogram features Logistic model tree(LMT) Tyre pressure monitoring system
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Unsupervised Log Anomaly Detection Method Based on Multi-Feature 被引量:2
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作者 Shiming He Tuo Deng +2 位作者 Bowen Chen R.Simon Sherratt Jin Wang 《Computers, Materials & Continua》 SCIE EI 2023年第7期517-541,共25页
Log anomaly detection is an important paradigm for system troubleshooting.Existing log anomaly detection based on Long Short-Term Memory(LSTM)networks is time-consuming to handle long sequences.Transformer model is in... Log anomaly detection is an important paradigm for system troubleshooting.Existing log anomaly detection based on Long Short-Term Memory(LSTM)networks is time-consuming to handle long sequences.Transformer model is introduced to promote efficiency.However,most existing Transformer-based log anomaly detection methods convert unstructured log messages into structured templates by log parsing,which introduces parsing errors.They only extract simple semantic feature,which ignores other features,and are generally supervised,relying on the amount of labeled data.To overcome the limitations of existing methods,this paper proposes a novel unsupervised log anomaly detection method based on multi-feature(UMFLog).UMFLog includes two sub-models to consider two kinds of features:semantic feature and statistical feature,respectively.UMFLog applies the log original content with detailed parameters instead of templates or template IDs to avoid log parsing errors.In the first sub-model,UMFLog uses Bidirectional Encoder Representations from Transformers(BERT)instead of random initialization to extract effective semantic feature,and an unsupervised hypersphere-based Transformer model to learn compact log sequence representations and obtain anomaly candidates.In the second sub-model,UMFLog exploits a statistical feature-based Variational Autoencoder(VAE)about word occurrence times to identify the final anomaly from anomaly candidates.Extensive experiments and evaluations are conducted on three real public log datasets.The results show that UMFLog significantly improves F1-scores compared to the state-of-the-art(SOTA)methods because of the multi-feature. 展开更多
关键词 System log anomaly detection semantic features statistical features TRANSFORMER
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Health Monitoring of Dry Clutch System Using Deep Learning Approach
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作者 Ganjikunta Chakrapani V.Sugumaran 《Intelligent Automation & Soft Computing》 SCIE 2023年第8期1513-1530,共18页
Clutch is one of the most significant components in automobiles.To improve passenger safety,reliability and economy of automobiles,advanced supervision and fault diagnostics are required.Condition Monitoring is one of... Clutch is one of the most significant components in automobiles.To improve passenger safety,reliability and economy of automobiles,advanced supervision and fault diagnostics are required.Condition Monitoring is one of the key divisions that can be used to track the reliability of clutch and allied components.The state of the clutch elements can be monitored with the help of vibration signals which contain valuable information required for classification.Specific drawbacks of traditional fault diagnosis techniques like high reliability on human intelligence and the requirement of profes-sional expertise,have made researchers look for intelligent fault diagnosis techniques.In this article,the classification performance of the deep learning technique(employing images plotted from vibration signals)is compared with the machine learning technique(using features extracted from vibration signals)to identify the most viable solution for condition monitoring of the clutch system.The overall experimentation is carried out in two phases,namely the deep learning phase and the machine learning phase.Overall,the effectiveness of the pre-trained networks was assessed and compared with machine learning algorithms.Based on the comparative study,the best-performing technique is recommended for real-time application. 展开更多
关键词 Deep learning health monitoring pre-trained models transfer learning vibration analysis statistical features
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Improved Ant Colony Optimization and Machine Learning Based Ensemble Intrusion Detection Model
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作者 S.Vanitha P.Balasubramanie 《Intelligent Automation & Soft Computing》 SCIE 2023年第4期849-864,共16页
Internet of things(IOT)possess cultural,commercial and social effect in life in the future.The nodes which are participating in IOT network are basi-cally attracted by the cyber-attack targets.Attack and identification... Internet of things(IOT)possess cultural,commercial and social effect in life in the future.The nodes which are participating in IOT network are basi-cally attracted by the cyber-attack targets.Attack and identification of anomalies in IoT infrastructure is a growing problem in the IoT domain.Machine Learning Based Ensemble Intrusion Detection(MLEID)method is applied in order to resolve the drawback by minimizing malicious actions in related botnet attacks on Message Queue Telemetry Transport(MQTT)and Hyper-Text Transfer Proto-col(HTTP)protocols.The proposed work has two significant contributions which are a selection of features and detection of attacks.New features are chosen from Improved Ant Colony Optimization(IACO)in the feature selection,and then the detection of attacks is carried out based on a combination of their possible proper-ties.The IACO approach is focused on defining the attacker’s important features against HTTP and MQTT.In the IACO algorithm,the constant factor is calculated against HTTP and MQTT based on the mean function for each element.Attack detection,the performance of several machine learning models are Distance Deci-sion Tree(DDT),Adaptive Neuro-Fuzzy Inference System(ANFIS)and Mahala-nobis Distance Support Vector Machine(MDSVM)were compared with predicting accurate attacks on the IoT network.The outcomes of these classifiers are combined into the ensemble model.The proposed MLEID strategy has effec-tively established malicious incidents.The UNSW-NB15 dataset is used to test the MLEID technique using data from simulated IoT sensors.Besides,the pro-posed MLEID technique has a greater detection rate and an inferior rate of false-positive compared to other conventional techniques. 展开更多
关键词 Network intrusion detection system(NIDS) internet of things(IOT) ensemble learning statisticalflow features BOTNET ensemble technique improved ant colony optimization(IACO) feature selection
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A Novel MDFA-MKECA Method With Application to Industrial Batch Process Monitoring 被引量:4
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作者 Yinghua Yang Xiang Shi +1 位作者 Xiaozhi Liu Hongru Li 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2020年第5期1446-1454,共9页
For the complex batch process with characteristics of unequal batch data length,a novel data-driven batch process monitoring method is proposed based on mixed data features analysis and multi-way kernel entropy compon... For the complex batch process with characteristics of unequal batch data length,a novel data-driven batch process monitoring method is proposed based on mixed data features analysis and multi-way kernel entropy component analysis(MDFA-MKECA)in this paper.Combining the mechanistic knowledge,different mixed data features of each batch including statistical and thermodynamics entropy features,are extracted to finish data pre-processing.After that,MKECA is applied to reduce data dimensionality and finally establish a monitoring model.The proposed method is applied to a reheating furnace industry process,and the experimental results demonstrate that the MDFA-MKECA method can reduce the calculated amount and effectively provide on-line monitoring of the batch process. 展开更多
关键词 MDFA MKECA process monitoring reheating furnace statistical features thermodynamics entropy feature
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Vibration Based Tool Insert Health Monitoring Using Decision Tree and Fuzzy Logic 被引量:1
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作者 Kundur Shantisagar R.Jegadeeshwaran +1 位作者 G.Sakthivel T.M.Alamelu Manghai 《Structural Durability & Health Monitoring》 EI 2019年第3期303-316,共14页
The productivity and quality in the turning process can be improved by utilizing the predicted performance of the cutting tools.This research incorporates condition monitoring of a non-carbide tool insert using vibrat... The productivity and quality in the turning process can be improved by utilizing the predicted performance of the cutting tools.This research incorporates condition monitoring of a non-carbide tool insert using vibration analysis along with machine learning and fuzzy logic approach.A non-carbide tool insert is considered for the process of cutting operation in a semi-automatic lathe,where the condition of tool is monitored using vibration characteristics.The vibration signals for conditions such as heathy,damaged,thermal and flank were acquired with the help of piezoelectric transducer and data acquisition system.The descriptive statistical features were extracted from the acquired vibration signal using the feature extraction techniques.The extracted statistical features were selected using a feature selection process through J48 decision tree algorithm.The selected features were classified using J48 decision tree and fuzzy to develop the fault diagnosis model for the improved predictive analysis.The decision tree model produced the classification accuracy as 94.78%with five selected features.The developed fuzzy model produced the classification accuracy as 94.02%with five membership functions.Hence,the decision tree has been proposed as a suitable fault diagnosis model for predicting the tool insert health condition under different fault conditions. 展开更多
关键词 statistical features J48 decision tree algorithm confusion matrix fuzzy logic WEKA
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Condition Monitoring of Roller Bearing by K-star Classifier andK-nearest Neighborhood Classifier Using Sound Signal
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作者 Rahul Kumar Sharma V.Sugumaran +1 位作者 Hemantha Kumar M.Amarnath 《Structural Durability & Health Monitoring》 EI 2017年第1期1-17,共17页
Most of the machineries in small or large-scale industry have rotating elementsupported by bearings for rigid support and accurate movement. For proper functioning ofmachinery, condition monitoring of the bearing is v... Most of the machineries in small or large-scale industry have rotating elementsupported by bearings for rigid support and accurate movement. For proper functioning ofmachinery, condition monitoring of the bearing is very important. In present study soundsignal is used to continuously monitor bearing health as sound signals of rotatingmachineries carry dynamic information of components. There are numerous studies inliterature that are reporting superiority of vibration signal of bearing fault diagnosis.However, there are very few studies done using sound signal. The cost associated withcondition monitoring using sound signal (Microphone) is less than the cost of transducerused to acquire vibration signal (Accelerometer). This paper employs sound signal forcondition monitoring of roller bearing by K-star classifier and k-nearest neighborhoodclassifier. The statistical feature extraction is performed from acquired sound signals. Thentwo-layer feature selection is done using J48 decision tree algorithm and random treealgorithm. These selected features were classified using K-star classifier and k-nearestneighborhood classifier and parametric optimization is performed to achieve the maximumclassification accuracy. The classification results for both K-star classifier and k-nearestneighborhood classifier for condition monitoring of roller bearing using sound signals werecompared. 展开更多
关键词 K-star k-nearest neighborhood K-NN machine learning approach conditionmonitoring fault diagnosis roller bearing decision tree algorithm J-48 random treealgorithm decision making two-layer feature selection sound signal statistical features
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Feature-Based Vibration Monitoring of a Hydraulic Brake System Using Machine Learning
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作者 T.M.Alamelu Manghai R.Jegadeeshwaran 《Structural Durability & Health Monitoring》 EI 2017年第2期149-167,共19页
Hydraulic brakes in automobiles are an important control component used not only for the safety of the passenger but also for others moving on the road.Therefore,monitoring the condition of the brake components is ine... Hydraulic brakes in automobiles are an important control component used not only for the safety of the passenger but also for others moving on the road.Therefore,monitoring the condition of the brake components is inevitable.The brake elements can be monitored by studying the vibration characteristics obtained from the brake system using a proper signal processing technique through machine learning approaches.The vibration signals were captured using an accelerometer sensor under a various fault condition.The acquired vibration signals were processed for extracting meaningful information as features.The condition of the brake system can be predicted using a feature based machine learning approach through the extracted features.This study focuses on a mechatronics system for data acquisitions and a signal processing technique for extracting features such as statistical,histogram and wavelets.Comparative results have been carried out using an experimental study for finding the effectiveness of the suggested signal processing techniques for monitoring the condition of the brake system. 展开更多
关键词 Vibration signals statistical features histogram features wavelet decomposition machine learning decision tree
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A Comparative Study of Bayes Classifiers for Blade Fault Diagnosis in Wind Turbines through Vibration Signals
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作者 A.Joshuva V.Sugumaran 《Structural Durability & Health Monitoring》 EI 2017年第1期63-79,共17页
Renewable energy sources are considered much in energy fields because of thecontemporary energy calamities. Among the important alternatives being considered, windenergy is a durable competitor because of its dependab... Renewable energy sources are considered much in energy fields because of thecontemporary energy calamities. Among the important alternatives being considered, windenergy is a durable competitor because of its dependability due to the development of theinnovations, comparative cost effectiveness and great framework. To yield wind energymore proficiently, the structure of wind turbines has turned out to be substantially bigger,creating conservation and renovation works troublesome. Due to various ecologicalconditions, wind turbine blades are subjected to vibration and it leads to failure. If thefailure is not diagnosed early, it will lead to catastrophic damage to the framework. In orderto increase safety observations, to reduce down time, to bring down the recurrence ofunexpected breakdowns and related enormous maintenance, logistic expenditures and tocontribute steady power generation, the wind turbine blade must be monitored now andthen to assure that they are in good condition. In this paper, a three bladed wind turbinewas preferred and using vibration source, the condition of a wind turbine blade is examined.The faults like blade crack, erosion, hub-blade loose connection, pitch angle twist and bladebend faults were considered and these faults are classified using Bayes Net (BN),Discriminative Multinomial Naïve Bayes (DMNB), Naïve Bayes (NB), Simple NaïveBayes (SNB), and Updateable Naïve Bayes (UNB) classifiers. These classifiers arecompared and better classifier is suggested for condition monitoring of wind turbine blades. 展开更多
关键词 Condition monitoring fault diagnosis wind turbine blade machine learning statistical features vibration signals
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Iris Recognition Based on Multilevel Thresholding Technique and Modified Fuzzy c-Means Algorithm
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作者 Slim Ben Chaabane Rafika Harrabi +1 位作者 Anas Bushnag Hassene Seddik 《Journal on Artificial Intelligence》 2022年第4期201-214,共14页
Biometrics represents the technology for measuring the characteristics of the human body.Biometric authentication currently allows for secure,easy,and fast access by recognizing a person based on facial,voice,and fing... Biometrics represents the technology for measuring the characteristics of the human body.Biometric authentication currently allows for secure,easy,and fast access by recognizing a person based on facial,voice,and fingerprint traits.Iris authentication is one of the essential biometric methods for identifying a person.This authentication type has become popular in research and practical applications.Unlike the face and hands,the iris is an internal organ,protected and therefore less likely to be damaged.However,the number of helpful information collected from the iris is much greater than the other biometric human organs.This work proposes a new iris identification model based on a multilevel thresholding technique and modified Fuzzy cmeans algorithm.The multilevel thresholding technique extracts the iris from its surroundings,such as specular reflections,eyelashes,pupils,and sclera.On the other hand,the modified Fuzzy c-means is used to combine and classify the most useful statistical features to maximize the accuracy of the collected information.Therefore,having the most optimal iris recognition.The proposed model results are validated using True Success Rate(TSR)and compared to other existing models.The results show how effective the combination of the two stages of the proposed model is:the Otsu method and modified Fuzzy c-means for the 400 tested images representing 40 people. 展开更多
关键词 Biometric authentication RECOGNITION iris recognition statistical features feature extraction fuzzy c-means TSR sensitivity classification
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Spur Gear Tooth Pitting Propagation Assessment Using Model-based Analysis 被引量:12
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作者 Xi-Hui Liang Zhi-Liang Liu +1 位作者 Jun Pan Ming Jian Zuo 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2017年第6期1369-1382,共14页
Tooth pitting is a common failure mode of a gearbox. Many researchers investigated dynamic properties of a gearbox with localized pitting damage on a single gear tooth. The dynamic properties of a gearbox with pitting... Tooth pitting is a common failure mode of a gearbox. Many researchers investigated dynamic properties of a gearbox with localized pitting damage on a single gear tooth. The dynamic properties of a gearbox with pitting distributed over multiple teeth have rarely been investi- gated. In this paper, gear tooth pitting propagation to neighboring teeth is modeled and investigated for a pair of spur gears. Tooth pitting propagation effect on time-vary- ing mesh stiffness, gearbox dynamics and vibration char- acteristics is studied and then fault symptoms are revealed. In addition, the influence of gear mesh damping and environmental noise on gearbox vibration properties is investigated. In the end, 114 statistical features are tested to estimate tooth pitting growth. Statistical features that are insensitive to gear mesh damping and environmental noise are recommended. 展开更多
关键词 Mesh stiffness Mesh damping Geardynamics Vibration statistical feature Dynamicsimulation
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RELATIONSHIP BETWEEN THE 30 TO 60 DAY OSCILLATION OF ATMOSPHERIC HEAT SOURCE AND THE DROUGHT AND FLOOD EVENTS IN JUNE IN THE SOUTH OF CHINA 被引量:2
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作者 高斯 简茂球 乔云亭 《Journal of Tropical Meteorology》 SCIE 2012年第3期332-340,共9页
Based on the NCEP/NCAR reanalysis data and the observed precipitation data in the south of China from 1958 to 2000,the impact of 30 to 60 day oscillation of atmospheric heat sources on the drought and flood events in ... Based on the NCEP/NCAR reanalysis data and the observed precipitation data in the south of China from 1958 to 2000,the impact of 30 to 60 day oscillation of atmospheric heat sources on the drought and flood events in June in the south of China is discussed.During the flood(drought) events,there exists an anomalous low-frequency anticyclone(cyclone) at the low level of the troposphere over the South China Sea and the northwestern Pacific,accompanied with anomalous low-frequency heat sinks(heat sources),while there exists an anomalous low-frequency cyclone(anticyclone) with anomalous heat sources(sinks) over the area from the south of China to the south of Japan.On average,the phase evolution of the low-frequency in drought events is 7 to 11 days ahead of that in flood events in May to June in the south of China.In flood events,low-frequency heat sources and cyclones are propagated northward from the southern South China Sea,northwestward from the warm pool of the western Pacific and westward from the northwestern Pacific around 140°E,which have very important impact on the abundant rainfall in June in the south of China.However,in drought events,the northward propagations of the low-frequency heat sources and cyclones from the South China Sea and its vicinity are rather late compared with those in flood events,and there is no obvious westward propagation of the heat sources from the northwestern Pacific.The timing of the low-frequency heat source propagation has remarkable impact on the June rainfall in the south of China. 展开更多
关键词 CLIMATOLOGY statistical feature atmospheric heat source 30-60 day oscillation flood and drought the south of China
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Single Point Cutting Tool Fault Diagnosis in Turning Operation Using Reduced Error Pruning Tree Classifier
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作者 E.Akshay V.Sugumaran M.Elangovan 《Structural Durability & Health Monitoring》 EI 2022年第3期255-270,共16页
Tool wear is inevitable in daily machining process since metal cutting process involves the chip rubbing the tool surface after it has been cut by the tool edge.Tool wear dominantly influences the deterioration of sur... Tool wear is inevitable in daily machining process since metal cutting process involves the chip rubbing the tool surface after it has been cut by the tool edge.Tool wear dominantly influences the deterioration of surface finish,geometric and dimensional tolerances of the workpiece.Moreover,for complete utilization of cutting tools and reduction of machine downtime during the machining process,it becomes necessary to understand the develop-ment of tool wear and predict its status before happening.In this study,tool condition monitoring system was used to monitor the behavior of a single point cutting tool to predict flank wear.A uniaxial accelerometer was attached to a single point cutting tool under study.The accelerometer acquires vibrational signals during turning operation on a lathe machine.The acquired signals were then used to extract statistical features such as standard error,variance,skewness,etc.The substantial features were recognized to reduce the utilization of computing resources.They were used to classify the signals as good and three different measures of flank wear by a decision tree algorithm.Frequency domain features were also extracted and shown to be less effective in classification in comparison to statistical features.REPTree(Reduced Error Pruning Tree)algorithm was used in this study.REPTree decision tree algorithm achieved a maximum classification accuracy of 72.77%for all signals combined.When spindle speed and feed rate are considered as the variables the accuracy is about 86.25%.When spindle speed is the only variable parameter the accuracy is about 82.71%.When depth of cut,feed rate and speed of the spindle are considered as variable parameters,the accuracy of the decision tree is around 93.51%.This study demonstrates the performance of REPTree classifier in tool condition monitoring.It can be utilized for tool wear identification and thus improve surface finish,dimensional accuracy of the work piece and reduce machine down-time.Any additional research on the work may involve analysis of different classifier algorithms which could potentially predict tool wear with greater accuracy. 展开更多
关键词 Fault diagnosis tool condition monitoring REPTree decision tree statistical feature extraction
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Research on seismic intensity zonation by use of the response intensity of historical earth-quakes───with the central part of Shanxi Province as an example
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作者 贾素娟 鄢家全 《Acta Seismologica Sinica(English Edition)》 CSCD 1996年第4期109-121,共13页
With the central part of Shanxi Province as an example, this paper studied seismic intensity zonation directly by use of the response intensity of historical earthquakes. From the result, some conclusions can be drawn... With the central part of Shanxi Province as an example, this paper studied seismic intensity zonation directly by use of the response intensity of historical earthquakes. From the result, some conclusions can be drawn as follows: ① For areas rich in data of historical earthquakes, the seismic intensity zonation map with probabilistic meanings can be compiled by use of the statistical features of the response intensity of sites; ② When determining the length of time for statistics, the completeness of response intensity data and the inhomogeneity of regional seismic activities should be fully considered; ③ By comparing the seismic intensity zonation result for recurrence interval of 500 years with the new Seismic Intensity Zonation Map of China (1990), it has been found that the two are roughly similar; though they are somewhat different for some localities, each has its own reasonableness. 展开更多
关键词 response intensity seismic intensity zonation statistical feature.
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A Novel Parsimonious Neurofuzzy Model Applied to Railway Carriage System Identification and Fault Diagnosis 被引量:1
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作者 S.C.Zhou O.L.Shuai +1 位作者 T.T.Wong T.P.Leung 《International Journal of Plant Engineering and Management》 1997年第4期7-11,共5页
In this paper, we suggest a novel parsimonious neurofuzzy model realized by RBFNs for railway carriage system identification and fault diagnosis. To overcome the curse of dimensionality resulting from high dimensional... In this paper, we suggest a novel parsimonious neurofuzzy model realized by RBFNs for railway carriage system identification and fault diagnosis. To overcome the curse of dimensionality resulting from high dimensional input variables, in our developed model the features extracted from the available observations are regarded as the input variables by adopting the higher-order statistics(HOS) technique. Such a constructed model is also applied to a practical railway carriage system, simulation results indicate that the developed neurofuzzy model possesses strong identification and fault diagnosis ability. 展开更多
关键词 parsimonious neurofuzzy model feature extraction by Higher-Order Statistics (HOS) railway carriage system identification and fault diagnosis
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REVERSE MODELING FOR CONIC BLENDING FEATURE
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作者 Fan Shuqian Ke Yinglin 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2005年第4期482-489,共8页
A novel method to extract conic blending feature in reverse engineering is presented. Different from the methods to recover constant and variable radius blends from unorganized points, it contains not only novel segme... A novel method to extract conic blending feature in reverse engineering is presented. Different from the methods to recover constant and variable radius blends from unorganized points, it contains not only novel segmentation and feature recognition techniques, but also bias corrected technique to capture more reliable distribution of feature parameters along the spine curve. The segmentation depending on point classification separates the points in the conic blend region from the input point cloud. The available feature parameters of the cross-sectional curves are extracted with the processes of slicing point clouds with planes, conic curve fitting, and parameters estimation and compensation, The extracted parameters and its distribution laws are refined according to statistic theory such as regression analysis and hypothesis test. The proposed method can accurately capture the original design intentions and conveniently guide the reverse modeling process. Application examples are presented to verify the high precision and stability of the proposed method. 展开更多
关键词 Computer-aided design Reverse engineering Feature recognition Geometric modeling Statistic theory Blending surface
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Condition monitoring and fault diagnosis strategy of railway point machines using vibration signals
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作者 Yongkui Sun Yuan Cao +2 位作者 Haitao Liu Weifeng Yang Shuai Su 《Transportation Safety and Environment》 EI 2023年第2期27-37,共11页
Condition monitoring of railway point machines is important for train operation safety and effectiveness.Referring to the fields of mechanical equipment fault detection,this paper proposes a fault detection and identi... Condition monitoring of railway point machines is important for train operation safety and effectiveness.Referring to the fields of mechanical equipment fault detection,this paper proposes a fault detection and identification strategy of railway point machines via vibration signals.A comprehensive feature distilling approach by combining variational mode decomposition(VMD)energy entropy and time-and frequency-domain statistical features is presented,which is more effective than single type of feature.The optimal set of features was selected with ReliefF,which helps improve the diagnosis accuracy.Support vector machine(SVM),which is suitable for a small sample,is adopted to realize diagnosis.The diagnosis accuracy of the proposed method reaches 100%,and its effectiveness is verified by experiment comparisons.In this paper,vibration signals are creatively adopted for fault diagnosis of railway point machines.The presented method can help guide field maintenance staff and also provide reference for fault diagnosis of other equipment. 展开更多
关键词 railway point machines condition monitoring variational mode decomposition(VMD)energy entropy statistical features
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