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DC-FIPD: Fraudulent IP Identification Method Based on Homology Detection
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作者 Yuanyuan Ma Ang Chen +3 位作者 Cunzhi Hou Ruixia Jin Jinghui Zhang Ruixiang Li 《Computers, Materials & Continua》 SCIE EI 2024年第11期3301-3323,共23页
Currently,telecom fraud is expanding from the traditional telephone network to the Internet,and identifying fraudulent IPs is of great significance for reducing Internet telecom fraud and protecting consumer rights.Ho... Currently,telecom fraud is expanding from the traditional telephone network to the Internet,and identifying fraudulent IPs is of great significance for reducing Internet telecom fraud and protecting consumer rights.However,existing telecom fraud identification methods based on blacklists,reputation,content and behavioral characteristics have good identification performance in the telephone network,but it is difficult to apply to the Internet where IP(Internet Protocol)addresses change dynamically.To address this issue,we propose a fraudulent IP identification method based on homology detection and DBSCAN(Density-Based Spatial Clustering of Applications with Noise)clustering(DC-FIPD).First,we analyze the aggregation of fraudulent IP geographies and the homology of IP addresses.Next,the collected fraudulent IPs are clustered geographically to obtain the regional distribution of fraudulent IPs.Then,we constructed the fraudulent IP feature set,used the genetic optimization algorithm to determine the weights of the fraudulent IP features,and designed the calculation method of the IP risk value to give the risk value threshold of the fraudulent IP.Finally,the risk value of the target IP is calculated and the IP is identified based on the risk value threshold.Experimental results on a real-world telecom fraud detection dataset show that the DC-FIPD method achieves an average identification accuracy of 86.64%for fraudulent IPs.Additionally,the method records a precision of 86.08%,a recall of 45.24%,and an F1-score of 59.31%,offering a comprehensive evaluation of its performance in fraud detection.These results highlight the DC-FIPD method’s effectiveness in addressing the challenges of fraudulent IP identification. 展开更多
关键词 Fraudulent IP identification homology detection CLUSTERING genetic optimization algorithm telecom fraud identification
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The Machine Learning Ensemble for Analyzing Internet of Things Networks:Botnet Detection and Device Identification
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作者 Seung-Ju Han Seong-Su Yoon Ieck-Chae Euom 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第11期1495-1518,共24页
The rapid proliferation of Internet of Things(IoT)technology has facilitated automation across various sectors.Nevertheless,this advancement has also resulted in a notable surge in cyberattacks,notably botnets.As a re... The rapid proliferation of Internet of Things(IoT)technology has facilitated automation across various sectors.Nevertheless,this advancement has also resulted in a notable surge in cyberattacks,notably botnets.As a result,research on network analysis has become vital.Machine learning-based techniques for network analysis provide a more extensive and adaptable approach in comparison to traditional rule-based methods.In this paper,we propose a framework for analyzing communications between IoT devices using supervised learning and ensemble techniques and present experimental results that validate the efficacy of the proposed framework.The results indicate that using the proposed ensemble techniques improves accuracy by up to 1.7%compared to single-algorithm approaches.These results also suggest that the proposed framework can flexibly adapt to general IoT network analysis scenarios.Unlike existing frameworks,which only exhibit high performance in specific situations,the proposed framework can serve as a fundamental approach for addressing a wide range of issues. 展开更多
关键词 Internet of Things machine learning traffic analysis botnet detection device identification
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Detection and Identification of Phytoplasma of Cleome rutidosperma in Areca Palm Yellow Leaf Disease Field
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作者 Zhaowei LIN Xiaoqing NIU +3 位作者 Shida LONG Qinghua TANG Dejie YANG Weiwei SONG 《Plant Diseases and Pests》 2024年第4期7-12,共6页
[Objectives]The paper was to detect and identify the phytoplasma of Cleome rutidosperma in areca palm yellow leaf disease(YLD)field in Wenchang City,Hainan Province,China.[Methods]The nested PCR technique was employed... [Objectives]The paper was to detect and identify the phytoplasma of Cleome rutidosperma in areca palm yellow leaf disease(YLD)field in Wenchang City,Hainan Province,China.[Methods]The nested PCR technique was employed to amplify the phytoplasma 16S rDNA of C.rutidosperma samples,followed by sequence analysis.Concurrently,this study examined C.rutidosperma in YLD field,collecting symptomatic leaves for phytoplasma detection.[Results]The 16S rDNA sequence of the C.rutidosperma witches'-broom phytoplasma was found to be identical to that of the HNWC5 strain associated with areca palm yellows phytoplasma,leading to the identification of this phytoplasma as belonging to the 16SrII-A subgroup.Field investigations revealed a higher incidence of C.rutidosperma in areca palm fields,with symptoms of leaf yellows observed in six of these fields.Quantitative PCR(qPCR)analysis confirmed the presence of phytoplasma infection in these instances.[Conclusions]Through the analysis of geographical distribution,sequence alignment,and field occurrence data,a significant correlation has been identified between witches'broom disease and YLD.It is proposed that the former may act as an intermediate host for the areca palm yellows phytoplasma. 展开更多
关键词 Areca palm yellow leaf disease PHYTOPLASMA Cleome rutidosperma identification detection
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Application of Radial Basis Function Network in Sensor Failure Detection
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作者 钮永胜 赵新民 《Journal of Beijing Institute of Technology》 EI CAS 1999年第2期70-76,共7页
Aim To detect sensor failure in control system using a single sensor signal. Methods A neural predictor was designed based on a radial basis function network(RBFN), and the neural predictor learned the sensor sig... Aim To detect sensor failure in control system using a single sensor signal. Methods A neural predictor was designed based on a radial basis function network(RBFN), and the neural predictor learned the sensor signal on line with a hybrid algorithm composed of n means clustering and Kalman filter and then gave the estimation of the sensor signal at the next step. If the difference between the estimation and the actural values of the sensor signal exceeded a threshold, the sensor could be declared to have a failure. The choice of the failure detection threshold depends on the noise variance and the possible prediction error of neural predictor. Results and Conclusion\ The computer simulation results show the proposed method can detect sensor failure correctly for a gyro in an automotive engine. 展开更多
关键词 sensor failure failure detection radial basis function network(BRFN) on line learning
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Application of Wavelets Transform to Fault Detection in Rotorcraft UAV Sensor Failure 被引量:8
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作者 Jun-tong Qi Jian-da Han 《Journal of Bionic Engineering》 SCIE EI CSCD 2007年第4期265-270,共6页
This paper describes a novel wavelet-based approach to the detection of abrupt fault of Rotorcrafi Unmanned Aerial Vehicle (RUAV) sensor system. By use of wavelet transforms that accurately localize the characterist... This paper describes a novel wavelet-based approach to the detection of abrupt fault of Rotorcrafi Unmanned Aerial Vehicle (RUAV) sensor system. By use of wavelet transforms that accurately localize the characteristics of a signal both in the time and frequency domains, the occurring instants of abnormal status of a sensor in the output signal can be identified by the multi-scale representation of the signal. Once the instants are detected, the distribution differences of the signal energy on all decomposed wavelet scales of the signal before and after the instants are used to claim and classify the sensor faults. 展开更多
关键词 RUAV wavelet transform fault detection sensor failure
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Automated detection and identification of white-backed planthoppers in paddy fields using image processing 被引量:14
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作者 YAO Qing CHEN Guo-te +3 位作者 WANG Zheng ZHANG Chao YANG Bao-jun TANG Jian 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2017年第7期1547-1557,共11页
A survey of the population densities of rice planthoppers is important for forecasting decisions and efficient control. Tra- ditional manual surveying of rice planthoppers is time-consuming, fatiguing, and subjective.... A survey of the population densities of rice planthoppers is important for forecasting decisions and efficient control. Tra- ditional manual surveying of rice planthoppers is time-consuming, fatiguing, and subjective. A new three-layer detection method was proposed to detect and identify white-backed planthoppers (WBPHs, Sogatella furcifera (Horvath)) and their developmental stages using image processing. In the first two detection layers, we used an AdaBoost classifier that was trained on a histogram of oriented gradient (HOG) features and a support vector machine (SVM) classifier that was trained on Gabor and Local Binary Pattern (LBP) features to detect WBPHs and remove impurities. We achieved a detection rate of 85.6% and a false detection rate of 10.2%. In the third detection layer, a SVM classifier that was trained on the HOG features was used to identify the different developmental stages of the WBPHs, and we achieved an identification rate of 73.1%, a false identification rate of 23.3%, and a 5.6% false detection rate for the images without WBPHs. The proposed three-layer detection method is feasible and effective for the identification of different developmental stages of planthoppers on rice plants in paddy fields. 展开更多
关键词 white-backed planthopper developmental stage automated detection and identification image processing histogram of oriented gradient features gabor features local binary pattern features
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An Efficient Adaptive Failure Detection Mechanism for Cloud Platform Based on Volterra Series 被引量:6
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作者 LIN Rongheng WU Budan YANG Fangchun ZHAO Yao HOU Jinxuan 《China Communications》 SCIE CSCD 2014年第4期1-12,共12页
Failure detection module is one of important components in fault-tolerant distributed systems,especially cloud platform.However,to achieve fast and accurate detection of failure becomes more and more difficult especia... Failure detection module is one of important components in fault-tolerant distributed systems,especially cloud platform.However,to achieve fast and accurate detection of failure becomes more and more difficult especially when network and other resources' status keep changing.This study presented an efficient adaptive failure detection mechanism based on volterra series,which can use a small amount of data for predicting.The mechanism uses a volterra filter for time series prediction and a decision tree for decision making.Major contributions are applying volterra filter in cloud failure prediction,and introducing a user factor for different QoS requirements in different modules and levels of IaaS.Detailed implementation is proposed,and an evaluation is performed in Beijing and Guangzhou experiment environment. 展开更多
关键词 failure detection volterra filter decision tree SELF-ADAPTIVE cloud platform
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Output only modal identification and structural damage detection using time frequency & wavelet techniques 被引量:14
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作者 S.Nagarajaiah B.Basu 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2009年第4期583-605,共23页
The primary objective of this paper is to develop output only modal identification and structural damage detection. Identification of multi-degree of freedom (MDOF) linear time invariant (LTI) and linear time vari... The primary objective of this paper is to develop output only modal identification and structural damage detection. Identification of multi-degree of freedom (MDOF) linear time invariant (LTI) and linear time variant (LTV--due to damage) systems based on Time-frequency (TF) techniques--such as short-time Fourier transform (STFT), empirical mode decomposition (EMD), and wavelets--is proposed. STFT, EMD, and wavelet methods developed to date are reviewed in detail. In addition a Hilbert transform (HT) approach to determine frequency and damping is also presented. In this paper, STFT, EMD, HT and wavelet techniques are developed for decomposition of free vibration response of MDOF systems into their modal components. Once the modal components are obtained, each one is processed using Hilbert transform to obtain the modal frequency and damping ratios. In addition, the ratio of modal components at different degrees of freedom facilitate determination of mode shape. In cases with output only modal identification using ambient/random response, the random decrement technique is used to obtain free vibration response. The advantage of TF techniques is that they arc signal based; hence, can be used for output only modal identification. A three degree of freedom 1:10 scale model test structure is used to validate the proposed output only modal identification techniques based on STFT, EMD, HT, wavelets. Both measured free vibration and forced vibration (white noise) response are considered. The secondary objective of this paper is to show the relative ease with which the TF techniques can be used for modal identification and their potential for real world applications where output only identification is essential. Recorded ambient vibration data processed using techniques such as the random decrement technique can be used to obtain the free vibration response, so that further processing using TF based modal identification can be performed. 展开更多
关键词 Time-frequency methods short time Fourier transform Hilbert transform WAVELETS modal identification:output only structural health monitoring damage detection
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Gas Leakage Detection and Pressure Difference Identification by Asymmetric Differential Pressure Method 被引量:2
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作者 Yan Shi Jiaqi Chang +3 位作者 Yixuan Wang Xuelin Zhao Qingzhen Zhang Liman Yang 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2022年第2期150-158,共9页
Currently,the measurement methods for pneumatic system leakage include bubbling,ultrasonic,and pressure detection methods.These methods are sensitive to high-precision sensors,long detection times,and stable external ... Currently,the measurement methods for pneumatic system leakage include bubbling,ultrasonic,and pressure detection methods.These methods are sensitive to high-precision sensors,long detection times,and stable external environments.The traditional differential pressure method involves severe differential pressure fluctuations caused by environmental pressure fluctuations or electromagnetic noise interference of sensors,leading to inaccurate detection.In this paper,a differential pressure fitting method for an asymmetric differential pressure cylinder is proposed.It overcomes the limitation of the detection efficiency caused by the asynchronous temperature recovery of the two chambers in the asymmetric differential pressure method and uses the differential pressure substitution equation to replace the differential calculation of the differential pressure.The improved differential pressure method proposes an innovation based on the detection principle and calculation method.Additionally,the influence of the parameters in the differential pressure substitution equation on the leakage calculation results was simulated,and the specific physical significance of the parameters of the differential pressure substitution equation was explained.The experiments verified the fitting effect and proved the accuracy of this method.Compared with the traditional differential pressure method,the maximum leakage deviation of inhibition was 0.5 L/min.Therefore,this method can be used to detect leaks in air tanks. 展开更多
关键词 Leakage detection System identification Asymmetric tank PNEUMATICS MEASUREMENT Flow characteristics
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Metabonomic analysis of hepatitis B virus-induced liver failure:identification of potential diagnostic biomarkers by fuzzy support vector machine 被引量:11
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作者 Yong MAO Xin HUANG +3 位作者 Ke YU Hai-bin QU Chang-xiao LIU Yi-yu CHENG 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2008年第6期474-481,共8页
Hepatitis B virus (HBV)-induced liver failure is an emergent liver disease leading to high mortality. The severity of liver failure may be reflected by the profile of some metabolites. This study assessed the potent... Hepatitis B virus (HBV)-induced liver failure is an emergent liver disease leading to high mortality. The severity of liver failure may be reflected by the profile of some metabolites. This study assessed the potential of using metabolites as biomarkers for liver failure by identifying metabolites with good discriminative performance for its phenotype. The serum samples from 24 HBV-indueed liver failure patients and 23 healthy volunteers were collected and analyzed by gas chromatography-mass spectrometry (GC-MS) to generate metabolite profiles. The 24 patients were further grouped into two classes according to the severity of liver failure. Twenty-five eommensal peaks in all metabolite profiles were extracted, and the relative area values of these peaks were used as features for each sample. Three algorithms, F-test, k-nearest neighbor (KNN) and fuzzy support vector machine (FSVM) combined with exhaustive search (ES), were employed to identify a subset of metabolites (biomarkers) that best predict liver failure. Based on the achieved experimental dataset, 93.62% predictive accuracy by 6 features was selected with FSVM-ES and three key metabolites, glyeerie acid, cis-aeonitie acid and citric acid, are identified as potential diagnostic biomarkers. 展开更多
关键词 Metabolite profile analysis Potential diagnostic biomarker identification k-nearest neighbor (KNN) Fuzzy supportvector machine (FSVM) Exhaustive search (ES) Gas chromatography-mass spectrometry (GC-MS) Hepatitis B virus (HBV)-induced liver failure
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Non-coherent sequence detection scheme for satellite-based automatic identification system 被引量:1
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作者 Haosu Zhou Jianxin Wang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2017年第3期442-448,共7页
The satellite-based automatic identification system (AIS) receiver has to encounter the frequency offset caused by the Doppler effect and the oscillator instability. This paper proposes a non-coherent sequence detecti... The satellite-based automatic identification system (AIS) receiver has to encounter the frequency offset caused by the Doppler effect and the oscillator instability. This paper proposes a non-coherent sequence detection scheme for the satellite-based AIS signal transmitted over the white Gaussian noise channel. Based on the maximum likelihood estimation and a Viterbi decoder, the proposed scheme is capable of tolerating a frequency offset up to 5% of the symbol rate. The complexity of the proposed scheme is reduced by the state-complexity reduction, which is based on per-survivor processing. Simulation results prove that the proposed non-coherent sequence detection scheme has high robustness to frequency offset compared to the relative scheme when messages collision exists. 展开更多
关键词 non-coherent sequence detection scheme satellite based automatic identification system frequency offset messages collision Viterbi decoder
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An Efficient Fuzzy Logic Fault Detection and Identification Method of Photovoltaic Inverters 被引量:1
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作者 Mokhtar Aly Hegazy Rezk 《Computers, Materials & Continua》 SCIE EI 2021年第5期2283-2299,共17页
Fuzzy logic control(FLC)systems have found wide utilization in several industrial applications.This paper proposes a fuzzy logic-based fault detection and identification method for open-circuit switch fault in grid-ti... Fuzzy logic control(FLC)systems have found wide utilization in several industrial applications.This paper proposes a fuzzy logic-based fault detection and identification method for open-circuit switch fault in grid-tied photovoltaic(PV)inverters.Large installations and ambitious plans have been recently achieved for PV systems as clean and renewable power generation sources due to their improved environmental impacts and availability everywhere.Power converters represent the main parts for the grid integration of PV systems.However,PV power converters contain several power switches that construct their circuits.The power switches in PV systems are highly subjected to high stresses due to the continuously varying operating conditions.Moreover,the grid-tied systems represent nonlinear systems and the system model parameters are changing continuously.Consequently,the grid-tied PV systems have a nonlinear factor and the fault detection and identification(FDI)methods based on using mathematical models become more complex.The proposed fuzzy logic-based FDI(FL-FDI)method is based on employing the fuzzy logic concept for detecting and identifying the location of various switch faults.The proposed FL-FDI method is designed and extracted from the analysis and comparison of the various measured voltage/current components for the control purposes.Therefore,the proposed FL-FDI method does not require additional components or measurement circuits.Additionally,the proposed method can detect the faulty condition and also identify the location of the faulty switch for replacement and maintenance purposes.The proposed method can detect the faulty condition within only a single fundamental line period without the need for additional sensors and/or performing complex calculations or precise models.The proposed FL-FDI method is tested on the widely used T-type PV inverter system,wherein there are twelve different switches and the FDI process represents a challenging task.The results shows the superior and accurate performance of the proposed FL-FDI method. 展开更多
关键词 Fault detection and identification fuzzy logic T-type inverter photovoltaic(PV)
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SENSOR FAILURE DETECTION AND SIGNAL RECOVERY BASED ON BP NEURAL NETWORK
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作者 Niu Yongsheng Zhao Xinmin(Dept of Electrical Engineering, Harbin Institute of Technology,Harbin, 150001, China) 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 1997年第2期151-154,共4页
A study is given on the application of BP neural network (BPNN) in sensorfailure detection in control systems, and on the networ architecture desgn, the redun-dancy,the quickness and the insensitivity to sensor noise ... A study is given on the application of BP neural network (BPNN) in sensorfailure detection in control systems, and on the networ architecture desgn, the redun-dancy,the quickness and the insensitivity to sensor noise of the BPNN based sensor detec-tion methed. Besules, an exploration is made into tbe factors accounting for the quality ofsignal recovery for failed sensor using BPNN. The results reveal clearly that BPNN can besuccessfully used in sensor failure detection and data recovery. 展开更多
关键词 neural nets failure detection SENSORS signal recovery
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AN INTERNATIONAL VIEW OF DIFFERENT APPROACHES FOR FAULTS DETECTION AND IDENTIFICATION IN NUCLEAR POWER PLANTS
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作者 徐济鋆 《Journal of Shanghai Jiaotong university(Science)》 EI 2000年第2期114-120,124,共8页
An extensive survey of computer based systems that apply different approaches for faults diagnostics and identifications in nuclear power plants (NPPs) was presented. In the light of reviewed material, the classificat... An extensive survey of computer based systems that apply different approaches for faults diagnostics and identifications in nuclear power plants (NPPs) was presented. In the light of reviewed material, the classification criteria were developed. The classification of computational techniques (class of computing devices, class of programming languages, and simulation programs) was discussed. The classification of theoretical aspects applied (brief aspects, and detailed aspects) in computer based diagnostic systems were established. The classification of metholology applied (symbolic reasoning methodology, event based methodology, and function based methodology) in the diagnostic systems was also depicted. In the end, the personal comments on the reviewed material, and scope of the study were described. 展开更多
关键词 EXPERT systems artificial INTELLIGENCE FAULTS detection and identification NUCLEAR power PLANTS Document code:A
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Cyclic autocorrelation based blind OFDM detection and identification for cognitive radio 被引量:2
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作者 Ning Han Sung Hwan Sohn Jae Moung Kim 《通讯和计算机(中英文版)》 2009年第5期46-51,共6页
关键词 OFDM 信号处理 通信 无线电通信
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Mutation detection and fast identification of switching system based on data-driven method
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作者 张钟化 徐伟 宋怡 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第5期164-177,共14页
In the engineering field,switching systems have been extensively studied,where sudden changes of parameter value and structural form have a significant impact on the operational performance of the system.Therefore,it ... In the engineering field,switching systems have been extensively studied,where sudden changes of parameter value and structural form have a significant impact on the operational performance of the system.Therefore,it is important to predict the behavior of the switching system,which includes the accurate detection of mutation points and rapid reidentification of the model.However,few efforts have been contributed to accurately locating the mutation points.In this paper,we propose a new measure of mutation detection—the threshold-based switching index by analogy with the Lyapunov exponent.We give the algorithm for selecting the optimal threshold,which greatly reduces the additional data collection and the relative error of mutation detection.In the system identification part,considering the small data amount available and noise in the data,the abrupt sparse Bayesian regression(abrupt-SBR)method is proposed.This method captures the model changes by updating the previously identified model,which requires less data and is more robust to noise than identifying the new model from scratch.With two representative dynamical systems,we illustrate the application and effectiveness of the proposed methods.Our research contributes to the accurate prediction and possible control of switching system behavior. 展开更多
关键词 mutation detection switching index system identification sparse Bayesian regression
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Automatic System for Failure Detection in Hydro-Power Generators
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作者 Luis Carlos Ribeiro Levy Ely de Lacerda de Oliveira +4 位作者 Erik Leandro Bonaldi Luiz Eduardo Borges da Silva Camila Paes Salomon Jonas G. Borges da Silva Germano Lambert-Torres 《Journal of Power and Energy Engineering》 2014年第4期36-46,共11页
This paper presents an automatic system for failure detection in hydro-power generators. The main idea of this system is to detect failure using current and voltage signals acquired without any type of internal interf... This paper presents an automatic system for failure detection in hydro-power generators. The main idea of this system is to detect failure using current and voltage signals acquired without any type of internal interference in the generator operation. The detected failures could be mechanical or electrical origins, such as: problems in bearings, unwanted vibrations, partial discharges, misalignment, unbalancing, among others. It is possible because the generator acts as a transducer for mechanical problems, and they appear in current and voltage signals. This automatic system based on electric signature analysis has been installed in Itapebi Power Plant generators since 2012. Some results are presented in this paper. 展开更多
关键词 Automatic System ON-LINE Measurements Digital Signal Processing PREDICTIVE Maintenance failure detection
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Predicting heartbeat arrival time for failure detection over internet using auto-regressive exogenous model
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作者 赵海军 《High Technology Letters》 EI CAS 2008年第4期370-376,共7页
Predicting heartbeat message arrival time is crucial for the quality of failure detection service over intemet. However, intemet dynamic characteristics make it very difficult to understand message behavior and accura... Predicting heartbeat message arrival time is crucial for the quality of failure detection service over intemet. However, intemet dynamic characteristics make it very difficult to understand message behavior and accurately predict heartbeat arrival time. To solve this problem, a novel black-box model is proposed to predict the next heartbeat arrival time. Heartbeat arrival time is modeled as auto-regressive process, heartbeat sending time is modeled as exogenous variable, the model' s coefficients are estimated based on the sliding window of observations and this result is used to predict the next heartbeat arrival time. Simulation shows that this adaptive auto-regressive exogenous (ARX) model can accurately capture heartbeat arrival dynamics and minimize prediction error in different network environments. 展开更多
关键词 INTERACT failure detection ADAPTIVE HEARTBEAT PREDICTION
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Robust Principal Component Test in Gross Error Detection and Identification
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作者 高倩 阎威武 邵惠鹤 《Journal of Shanghai Jiaotong university(Science)》 EI 2007年第5期553-558,共6页
Principle component analysis (PCA) based chi-square test is more sensitive to subtle gross errors and has greater power to correctly detect gross errors than classical chi-square test. However, classical principal c... Principle component analysis (PCA) based chi-square test is more sensitive to subtle gross errors and has greater power to correctly detect gross errors than classical chi-square test. However, classical principal com- ponent test (PCT) is non-robust and can be very sensitive to one or more outliers. In this paper, a Huber function liked robust weight factor was added in the collective chi-square test to eliminate the influence of gross errors on the PCT. Meanwhile, robust chi-square test was applied to modified simultaneous estimation of gross error (MSEGE) strategy to detect and identify multiple gross errors. Simulation results show that the proposed robust test can reduce the possibility of type Ⅱ errors effectively. Adding robust chi-square test into MSEGE does not obviously improve the power of multiple gross error identification, the proposed approach considers the influence of outliers on hypothesis statistic test and is more reasonable. 展开更多
关键词 gross error detection and identification chi-square test ROBUST principle component analysis (PCA) modified simultaneous estimation of gross error (MSEGE)
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External Disturbance Detection and Its Application on the Identification of Fault in CMG System
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作者 Jung-Hyung Lee Hun-Jo Lee +1 位作者 Joon-Yong Lee Hwa-Suk Oh 《Journal of Energy and Power Engineering》 2018年第6期281-288,共8页
CMGs(control moment gyros)as satellite actuators have intrinsic structures generating disturbance,like bearings,motors,high-speed rotating wheels,steering gimbal,etc.Disturbances induced by faults in some of these par... CMGs(control moment gyros)as satellite actuators have intrinsic structures generating disturbance,like bearings,motors,high-speed rotating wheels,steering gimbal,etc.Disturbances induced by faults in some of these parts shall be detected immediately and identified in real time.A continuous second order sliding mode observer can be applied for the detection of disturbances.In this paper,a nonlinear sliding mode observing algorithm based on the gyro sensor is suggested for the detection of external disturbances.The algorithm is then applied to detect a fault in a CMG,here the wheel fluctuation fault.By distinguishing the direction of disturbance torque by a diagnosis algorithm,the fault CMG can be then identified and isolated from other normal CMGs.The performance of detecting algorithm is verified on the hardware satellite simulator,in which four CMGs are installed. 展开更多
关键词 Satellite ACTUATOR FAULT detection identification SLIDING mode OBSERVER
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