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Weak Fault Feature Extraction of the Rotating Machinery Using Flexible Analytic Wavelet Transform and Nonlinear Quantum Permutation Entropy
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作者 Lili Bai Wenhui Li +3 位作者 He Ren Feng Li TaoYan Lirong Chen 《Computers, Materials & Continua》 SCIE EI 2024年第6期4513-4531,共19页
Addressing the challenges posed by the nonlinear and non-stationary vibrations in rotating machinery,where weak fault characteristic signals hinder accurate fault state representation,we propose a novel feature extrac... Addressing the challenges posed by the nonlinear and non-stationary vibrations in rotating machinery,where weak fault characteristic signals hinder accurate fault state representation,we propose a novel feature extraction method that combines the Flexible Analytic Wavelet Transform(FAWT)with Nonlinear Quantum Permutation Entropy.FAWT,leveraging fractional orders and arbitrary scaling and translation factors,exhibits superior translational invariance and adjustable fundamental oscillatory characteristics.This flexibility enables FAWT to provide well-suited wavelet shapes,effectively matching subtle fault components and avoiding performance degradation associated with fixed frequency partitioning and low-oscillation bases in detecting weak faults.In our approach,gearbox vibration signals undergo FAWT to obtain sub-bands.Quantum theory is then introduced into permutation entropy to propose Nonlinear Quantum Permutation Entropy,a feature that more accurately characterizes the operational state of vibration simulation signals.The nonlinear quantum permutation entropy extracted from sub-bands is utilized to characterize the operating state of rotating machinery.A comprehensive analysis of vibration signals from rolling bearings and gearboxes validates the feasibility of the proposed method.Comparative assessments with parameters derived from traditional permutation entropy,sample entropy,wavelet transform(WT),and empirical mode decomposition(EMD)underscore the superior effectiveness of this approach in fault detection and classification for rotating machinery. 展开更多
关键词 Rotating machinery quantum theory nonlinear quantum permutation entropy Flexible Analytic Wavelet Transform(FAWT) feature extraction
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Entanglement and Volume Monogamy Features of Permutation Symmetric N-Qubit Pure States with N-Distinct Spinors: GHZ and States
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作者   Sudha Alevoor Raghavendra Usha Devi +4 位作者 Akshata Shenoy Hejamadi Hosapete Seshadri Karthik Humera Talath Bada Palaiah Govindaraja Attipat Krishnaswamy Rajagopal 《Journal of Quantum Information Science》 CAS 2024年第2期29-51,共23页
We explore the entanglement features of pure symmetric N-qubit states characterized by N-distinct spinors with a particular focus on the Greenberger-Horne-Zeilinger (GHZ) states and , an equal superposition of W and o... We explore the entanglement features of pure symmetric N-qubit states characterized by N-distinct spinors with a particular focus on the Greenberger-Horne-Zeilinger (GHZ) states and , an equal superposition of W and obverse W states. Along with a comparison of pairwise entanglement and monogamy properties, we explore the geometric information contained in them by constructing their canonical steering ellipsoids. We obtain the volume monogamy relations satisfied by states as a function of number of qubits and compare with the maximal monogamy property of GHZ states. 展开更多
关键词 permutation Symmetric States MONOGAMY Pairwise Entanglement
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Modified 2 Satisfiability Reverse Analysis Method via Logical Permutation Operator
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作者 Siti Zulaikha Mohd Jamaludin MohdAsyraf Mansor +3 位作者 Aslina Baharum Mohd Shareduwan Mohd Kasihmuddin Habibah A.Wahab Muhammad Fadhil Marsani 《Computers, Materials & Continua》 SCIE EI 2023年第2期2853-2870,共18页
The effectiveness of the logic mining approach is strongly correlated to the quality of the induced logical representation that represent the behaviour of the data.Specifically,the optimum induced logical representati... The effectiveness of the logic mining approach is strongly correlated to the quality of the induced logical representation that represent the behaviour of the data.Specifically,the optimum induced logical representation indicates the capability of the logic mining approach in generalizing the real datasets of different variants and dimensions.The main issues with the logic extracted by the standard logic mining techniques are lack of interpretability and the weakness in terms of the structural and arrangement of the 2 Satisfiability logic causing lower accuracy.To address the issues,the logical permutation serves as an alternative mechanism that can enhance the probability of the 2 Satisfiability logical rule becoming true by utilizing the definitive finite arrangement of attributes.This work aims to examine and analyze the significant effect of logical permutation on the performance of data extraction ability of the logic mining approach incorporated with the recurrent discrete Hopfield Neural Network.Based on the theory,the effect of permutation and associate memories in recurrent Hopfield Neural Network will potentially improve the accuracy of the existing logic mining approach.To validate the impact of the logical permutation on the retrieval phase of the logic mining model,the proposed work is experimentally tested on a different class of the benchmark real datasets ranging from the multivariate and timeseries datasets.The experimental results show the significant improvement in the proposed logical permutation-based logic mining according to the domains such as compatibility,accuracy,and competitiveness as opposed to the plethora of standard 2 Satisfiability Reverse Analysis methods. 展开更多
关键词 Logic mining logical permutation discrete hopfield neural network knowledge extraction
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Cloud Resource Integrated Prediction Model Based on Variational Modal Decomposition-Permutation Entropy and LSTM
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作者 Xinfei Li Xiaolan Xie +1 位作者 Yigang Tang Qiang Guo 《Computer Systems Science & Engineering》 SCIE EI 2023年第11期2707-2724,共18页
Predicting the usage of container cloud resources has always been an important and challenging problem in improving the performance of cloud resource clusters.We proposed an integrated prediction method of stacking co... Predicting the usage of container cloud resources has always been an important and challenging problem in improving the performance of cloud resource clusters.We proposed an integrated prediction method of stacking container cloud resources based on variational modal decomposition(VMD)-Permutation entropy(PE)and long short-term memory(LSTM)neural network to solve the prediction difficulties caused by the non-stationarity and volatility of resource data.The variational modal decomposition algorithm decomposes the time series data of cloud resources to obtain intrinsic mode function and residual components,which solves the signal decomposition algorithm’s end-effect and modal confusion problems.The permutation entropy is used to evaluate the complexity of the intrinsic mode function,and the reconstruction based on similar entropy and low complexity is used to reduce the difficulty of modeling.Finally,we use the LSTM and stacking fusion models to predict and superimpose;the stacking integration model integrates Gradient boosting regression(GBR),Kernel ridge regression(KRR),and Elastic net regression(ENet)as primary learners,and the secondary learner adopts the kernel ridge regression method with solid generalization ability.The Amazon public data set experiment shows that compared with Holt-winters,LSTM,and Neuralprophet models,we can see that the optimization range of multiple evaluation indicators is 0.338∼1.913,0.057∼0.940,0.000∼0.017 and 1.038∼8.481 in root means square error(RMSE),mean absolute error(MAE),mean absolute percentage error(MAPE)and variance(VAR),showing its stability and better prediction accuracy. 展开更多
关键词 Cloud resource prediction variational modal decomposition permutation entropy long and short-term neural network stacking integration
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Short-Term Prediction of Photovoltaic Power Generation Based on LMD Permutation Entropy and Singular Spectrum Analysis
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作者 Wenchao Ma 《Energy Engineering》 EI 2023年第7期1685-1699,共15页
The power output state of photovoltaic power generation is affected by the earth’s rotation and solar radiation intensity.On the one hand,its output sequence has daily periodicity;on the other hand,it has discrete ra... The power output state of photovoltaic power generation is affected by the earth’s rotation and solar radiation intensity.On the one hand,its output sequence has daily periodicity;on the other hand,it has discrete randomness.With the development of new energy economy,the proportion of photovoltaic energy increased accordingly.In order to solve the problem of improving the energy conversion efficiency in the grid-connected optical network and ensure the stability of photovoltaic power generation,this paper proposes the short-termprediction of photovoltaic power generation based on the improvedmulti-scale permutation entropy,localmean decomposition and singular spectrum analysis algorithm.Firstly,taking the power output per unit day as the research object,the multi-scale permutation entropy is used to calculate the eigenvectors under different weather conditions,and the cluster analysis is used to reconstruct the historical power generation under typical weather rainy and snowy,sunny,abrupt,cloudy.Then,local mean decomposition(LMD)is used to decompose the output sequence,so as to extract more detail components of the reconstructed output sequence.Finally,combined with the weather forecast of the Meteorological Bureau for the next day,the singular spectrumanalysis algorithm is used to predict the photovoltaic classification of the recombination decomposition sequence under typical weather.Through the verification and analysis of examples,the hierarchical prediction experiments of reconstructed and non-reconstructed output sequences are compared.The results show that the algorithm proposed in this paper is effective in realizing the short-term prediction of photovoltaic generator,and has the advantages of simple structure and high prediction accuracy. 展开更多
关键词 Photovoltaic power generation short term forecast multiscale permutation entropy local mean decomposition singular spectrum analysis
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两个一维总体分布相等性的permutation检验 被引量:4
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作者 黄群 林洁梅 赵佳因 《辽宁工程技术大学学报(自然科学版)》 CAS 北大核心 2012年第6期929-932,共4页
检验两个一维总体分布的相等性,采用理论证明和数值模拟的方法,在Prastgaard提出的Kolmogorov-Smirnov统计量T1及相应的permutation统计量T 1基础上,提出了基于K-S统计量的新统计量T2及相应的permutation统计量T 2,研究了在一维的情形... 检验两个一维总体分布的相等性,采用理论证明和数值模拟的方法,在Prastgaard提出的Kolmogorov-Smirnov统计量T1及相应的permutation统计量T 1基础上,提出了基于K-S统计量的新统计量T2及相应的permutation统计量T 2,研究了在一维的情形下T2与T 2的分布,并进行了数值模拟.结果表明:新统计量在原假设下有相同的极限分布,数值模拟结果优于原统计量.该方法对检验两总体分布的相等性有一定的参考价值. 展开更多
关键词 permutation方法 K-S统计量 permutation统计量 假设检验 统计推断 经验分布函数 极限分布 数值模拟
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REVERSIBLE LOGIC GATE NETWORK CASCADE BASED ON PERMUTATION GROUP 被引量:1
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作者 管致锦 秦小麟 戴华 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2008年第3期219-223,共5页
The cascade of reversible logic gate network with n inputs and n outputs forms a group isomorphic to the symmetric group S2^n. Characteristics of a number of gates from the set of all generalized Toffoli gates are stu... The cascade of reversible logic gate network with n inputs and n outputs forms a group isomorphic to the symmetric group S2^n. Characteristics of a number of gates from the set of all generalized Toffoli gates are studied. Any permutation Sn is proved to be generated by a n-cycle 9 and a permutation τ= (ij,ik) together. It shows that any neighboring 2-cycle permutation can be generated by at most two NOT gates without ancilla bit. Based on the above theory, a cascade algorithm for reversible logic gate networks is proposed. A reversible example of logic gate network cascade is given to show the correctness of the algorithm. 展开更多
关键词 logic gates cascade connection permutation group
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Bootstrap和Permutation方法在样本率多重比较中的应用 被引量:3
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作者 钱俊 陈平雁 《中国医院统计》 2008年第1期43-45,共3页
目的介绍Bootstrap和Permutation方法在样本率多重比较中的应用。方法调用SAS中的MULTTEST过程,编写程序实现样本率的两两比较和与控制组比较,并通过实例说明效果。结果运用Bootstrap和Permutation方法能较好解决样本率的多重比较问题... 目的介绍Bootstrap和Permutation方法在样本率多重比较中的应用。方法调用SAS中的MULTTEST过程,编写程序实现样本率的两两比较和与控制组比较,并通过实例说明效果。结果运用Bootstrap和Permutation方法能较好解决样本率的多重比较问题。结论使用Bootstrap和Permutation方法的SAS程序,简单明了,结果准确,使用方便。 展开更多
关键词 BOOTSTRAP permutation 样本率 多重比较
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Fractal sorting vector-based least significant bit chaotic permutation for image encryption 被引量:1
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作者 Yong-Jin Xian Xing-Yuan Wang +2 位作者 Ying-Qian Zhang Xiao-Yu Wang Xiao-Hui Du 《Chinese Physics B》 SCIE EI CAS CSCD 2021年第6期226-235,共10页
The image's least significant bit(LSB) covers lots of the details that have been commonly used in image encryption analysis. The newly proposed fractal sorting vector(FSV) and FSV-based LSB chaotic permutation(FSV... The image's least significant bit(LSB) covers lots of the details that have been commonly used in image encryption analysis. The newly proposed fractal sorting vector(FSV) and FSV-based LSB chaotic permutation(FSV-LSBCP) is a novel chaotic image encryption cryptosystem introduced in this article. The FSV-LSBCP effectively strengthens the security of the cryptographic scheme concerning the properties of the FSV. Key analysis, statistical analysis, resistance differential attack analysis, and resistance to cropping attacks and noise attacks are the focus of the suggested image encryption cryptosystem. The security experiment shows that the cryptosystem is adequate to achieve the desired degree of security. 展开更多
关键词 chaotic image encryption fractal sorting vector bit-level permutation FSV-based LSB chaotic permutation
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Matching spatial relation graphs using a constrained partial permutation strategy
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作者 徐晓刚 孙正兴 刘文印 《Journal of Southeast University(English Edition)》 EI CAS 2003年第3期236-239,共4页
A constrained partial permutation strategy is proposed for matching spatial relation graph (SRG), which is used in our sketch input and recognition system Smart Sketchpad for representing the spatial relationship amon... A constrained partial permutation strategy is proposed for matching spatial relation graph (SRG), which is used in our sketch input and recognition system Smart Sketchpad for representing the spatial relationship among the components of a graphic object. Using two kinds of matching constraints dynamically generated in the matching process, the proposed approach can prune most improper mappings between SRGs during the matching process. According to our theoretical analysis in this paper, the time complexity of our approach is O(n 2) in the best case, and O(n!) in the worst case, which occurs infrequently. The spatial complexity is always O(n) for all cases. Implemented in Smart Sketchpad, our proposed strategy is of good performance. 展开更多
关键词 spatial relation graph graph matching constrained partial permutation graphics recognition
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On the Representations of Γ1-Nonderanged Permutation Group gp
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作者 Ibrahim A. Aminu Ejima Ojonugwa Kazeem O. Aremu 《Advances in Pure Mathematics》 2016年第9期608-614,共7页
Representation theory is concerned with the ways of explaining or visualizing a group as a group of matrices. In this paper, we extend the permutation pattern of to a two-line notation. We consider the representations... Representation theory is concerned with the ways of explaining or visualizing a group as a group of matrices. In this paper, we extend the permutation pattern of to a two-line notation. We consider the representations of this non-deranged permutation group(p ≥ 5 and p a prime). Also we reveal some interesting properties and results of the character of where . 展开更多
关键词 Representation Non-Deranged permutation Group Γ1-permutation Group Fgp-Module CHARACTER
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Microseismic signal denoising by combining variational mode decomposition with permutation entropy 被引量:5
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作者 Zhang Xing-Li Cao Lian-Yue +2 位作者 Chen Yan Jia Rui-Sheng Lu Xin-Ming 《Applied Geophysics》 SCIE CSCD 2022年第1期65-80,144,145,共18页
Remarkable progress has been achieved on microseismic signal denoising in recent years,which is the basic component for rock-burst detection.However,its denoising effectiveness remains unsatisfactory.To extract the ef... Remarkable progress has been achieved on microseismic signal denoising in recent years,which is the basic component for rock-burst detection.However,its denoising effectiveness remains unsatisfactory.To extract the effective microseismic signal from polluted noisy signals,a novel microseismic signal denoising method that combines the variational mode decomposition(VMD)and permutation entropy(PE),which we denote as VMD–PE,is proposed in this paper.VMD is a recently introduced technique for adaptive signal decomposition,where K is an important decomposing parameter that determines the number of modes.VMD provides a predictable eff ect on the nature of detected modes.In this work,we present a method that addresses the problem of selecting an appropriate K value by constructing a simulation signal whose spectrum is similar to that of a mine microseismic signal and apply this value to the VMD–PE method.In addition,PE is developed to identify the relevant effective microseismic signal modes,which are reconstructed to realize signal filtering.The experimental results show that the VMD–PE method remarkably outperforms the empirical mode decomposition(EMD)–VMD filtering and detrended fl uctuation analysis(DFA)–VMD denoising methods of the simulated and real microseismic signals.We expect that this novel method can inspire and help evaluate new ideas in this field. 展开更多
关键词 DENOISING Microseismic signal permutation entropy Variational mode decomposition
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Walsh Spectral Characteristics and the Auto-Correlation Function Characteristics of Forming Orthomorphic Permutations of Multi-Output Functions 被引量:4
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作者 ZHAO Yaqun WANG Jue 《Wuhan University Journal of Natural Sciences》 CAS 2006年第6期1895-1898,共4页
Orthomorphic permutations have good characteristics in cryptosystems. In this paper, by using of knowledge about relation between orthomorphic permutations and multi-output functions, and conceptions of the generalize... Orthomorphic permutations have good characteristics in cryptosystems. In this paper, by using of knowledge about relation between orthomorphic permutations and multi-output functions, and conceptions of the generalized Walsh spectrum of multi-output functions and the auto-correlation function of multi-output functions to investigate the Walsh spectral characteristics and the auto-correlation function characteristics of orthormophic permutations, several results are obtained. 展开更多
关键词 orthomorphic permutation multi-output functions walsh spectral auto-correlation function
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Decryption of pure-position permutation algorithms 被引量:3
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作者 赵晓宇 陈刚 +2 位作者 张亶 王肖虹 董光昌 《Journal of Zhejiang University Science》 EI CSCD 2004年第7期803-809,共7页
Pure position permutation image encryption algorithms, commonly used as image encryption investigated in this work are unfortunately frail under known-text attack. In view of the weakness of pure position permutation ... Pure position permutation image encryption algorithms, commonly used as image encryption investigated in this work are unfortunately frail under known-text attack. In view of the weakness of pure position permutation algorithm,we put forward an effective decryption algorithm for all pure-position permutation algorithms. First, a summary of the pure position permutation image encryption algorithms is given by introducing the concept of ergodic matrices. Then, by using probability theory and algebraic principles, the decryption probability of pure-position permutation algorithms is verified theoretically; and then, by defining the operation system of fuzzy ergodic matrices, we improve a specific decryption al-gorithm. Finally, some simulation results are shown. 展开更多
关键词 DECRYPTION Image encryption FUZZY Position permutation
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Anomalies in Special Permutation Flow Shop Scheduling Problems 被引量:2
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作者 Lin Gui Liang Gao Xinyu Li 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2020年第3期53-59,共7页
Recent researches show that there are some anomalies,which are not satisfied with common sense,appearing in some special permutation flow shop scheduling problems(PFSPs).These anomalies can be divided into three diffe... Recent researches show that there are some anomalies,which are not satisfied with common sense,appearing in some special permutation flow shop scheduling problems(PFSPs).These anomalies can be divided into three different types,such as changing the processing time of some operations,changing the number of total jobs and changing the number of total machines.This paper summarizes these three types of anomalies showing in the special PFSPs and gives some examples to make them better understood.The extended critical path is proposed and the reason why these anomalies happen in special PFSPs is given:anomalies will occur in these special PFSPs when the time of the operations on the reverse critical path changes.After that,the further reason for these anomalies is presented that when any one of these three types of anomalies happens,the original constraint in the special PFSPs is destroyed,which makes the anomalies appear.Finally,the application of these anomalies in production practice is given through examples and also with the possible research directions.The main contribution of this research is analyzing the intial reason why the anomalies appear in special PFSPs and pointing out the application and the possible research directions of all these three types of anomalies. 展开更多
关键词 SCHEDULING permutation flow shop ANOMALY
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A WATERMARKING ALGORITHM BASED ON PERMUTATION AND 2-D BARCODE 被引量:2
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作者 Ji Zhen Zhang Jihong Xie Weixin (Faculty of Information Engineering, Shenzhen University, Shenzhen 518060) 《Journal of Electronics(China)》 2001年第4期375-381,共7页
This letter presents a method for digital image watermarking for copyright protection. This technique produces a watermarked image that closely retains the quality of the original host image while concurrently survivi... This letter presents a method for digital image watermarking for copyright protection. This technique produces a watermarked image that closely retains the quality of the original host image while concurrently surviving various image processing operations such as lowpass/highpass filtering, lossy JPEG compression, and cropping. This image watermarking algorithm takes full advantage of permutation and 2-D barcode (PDF417). The actual watermark embedding in spatial domain is followed using permutated image for improving the resistance to image cropping. Much higher watermark robustness is obtainable via a simple forward error correction technique, which is the main feature of PDF417 codes. Additional features of this technique include the easy determination of the existence of the watermark and that the watermark verification procedure does not need the original host image. The experimental results demonstrate its effectiveness. 展开更多
关键词 DIGITAL WATERMARK permutation 2-D BARCODE PDF417
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NEW CONSTRUCTIONS OF LDPC CODES BASED ON CIRCULANT PERMUTATION MATRICES FOR AWGN CHANNEL 被引量:2
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作者 Song Zixi Zhang Lijun 《Journal of Electronics(China)》 2014年第2期85-91,共7页
Two new design approaches for constructing Low-Density Parity-Check(LDPC) codes are proposed.One is used to design regular Quasi-Cyclic LDPC(QC-LDPC) codes with girth at least 8.The other is used to design irregular L... Two new design approaches for constructing Low-Density Parity-Check(LDPC) codes are proposed.One is used to design regular Quasi-Cyclic LDPC(QC-LDPC) codes with girth at least 8.The other is used to design irregular LDPC codes.Both of their parity-check matrices are composed of Circulant Permutation Matrices(CPMs).When iteratively decoded with the Sum-Product Algorithm(SPA),these proposed codes exhibit good performances over the AWGN channel. 展开更多
关键词 Circulant permutation Matrices(CPMs) Euclidean geometry Error floor Irregular LDPC codes Quasi-cyclic
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Morphology Similarity Distance for Bearing Fault Diagnosis Based on Multi-Scale Permutation Entropy 被引量:2
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作者 Jinbao Zhang Yongqiang Zhao +1 位作者 Lingxian Kong Ming Liu 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2020年第1期1-9,共9页
Bearings are crucial components in rotating machines,which have direct effects on industrial productivity and safety.To fast and accurately identify the operating condition of bearings,a novel method based on multi⁃sc... Bearings are crucial components in rotating machines,which have direct effects on industrial productivity and safety.To fast and accurately identify the operating condition of bearings,a novel method based on multi⁃scale permutation entropy(MPE)and morphology similarity distance(MSD)is proposed in this paper.Firstly,the MPE values of the original signals were calculated to characterize the complexity in different scales and they constructed feature vectors after normalization.Then,the MSD was employed to measure the distance among test samples from different fault types and the reference samples,and achieved classification with the minimum MSD.Finally,the proposed method was verified with two experiments concerning artificially seeded damage bearings and run⁃to⁃failure bearings,respectively.Different categories were considered for the two experiments and high classification accuracies were obtained.The experimental results indicate that the proposed method is effective and feasible in bearing fault diagnosis. 展开更多
关键词 bearing fault diagnosis multi⁃scale permutation entropy morphology similarity distance
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Hybrid artificial immune system and extremal optimization algorithm for permutation flowshop scheduling problem 被引量:2
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作者 孙凯 杨根科 《Journal of Shanghai University(English Edition)》 CAS 2008年第4期352-357,共6页
The permutation flowshop scheduling problem (PFSP) is one of the most well-known and well-studied production scheduling problems with strong industrial background. This paper presents a new hybrid optimization algor... The permutation flowshop scheduling problem (PFSP) is one of the most well-known and well-studied production scheduling problems with strong industrial background. This paper presents a new hybrid optimization algorithm which combines the strong global search ability of artificial immune system (AIS) with a strong local search ability of extremal optimization (EO) algorithm. The proposed algorithm is applied to a set of benchmark problems with a makespan criterion. Performance of the algorithm is evaluated. Comparison results indicate that this new method is an effective and competitive approach to the PFSP. 展开更多
关键词 artificial immune system (AIS) extremal optimization (EO) permutation flowshop scheduling problem (PFSP)
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Frame-indifference of cross products,rotations,and the permutation tensor 被引量:1
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作者 Maolin Du 《Theoretical & Applied Mechanics Letters》 CAS CSCD 2020年第2期116-119,共4页
Under improper transformations,the traditional transformation laws for cross products,the permutation tensor,and rotations are incorrect.For a cross product,using a counter-example the left-hand rule is proved wrong.T... Under improper transformations,the traditional transformation laws for cross products,the permutation tensor,and rotations are incorrect.For a cross product,using a counter-example the left-hand rule is proved wrong.The unique rule for a cross product is the right-hand rule.Coordinate systems have handedness,while a cross product is frame-indifference.Since the permutation tensor is defined as a triple product including a cross product,the law for the permutation tensor is false.For a rotation,its pseudovector representation is incorrect,because the mirror is an auxiliary device to produce the virtual image rather than a new coordinate system or reference frame. 展开更多
关键词 Pseudovector Cross product IMPROPER transformation Handed coefficient permutation TENSOR
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