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A method combining refined composite multiscale fuzzy entropy with PSO-SVM for roller bearing fault diagnosis 被引量:13
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作者 XU Fan Peter W TSE 《Journal of Central South University》 SCIE EI CAS CSCD 2019年第9期2404-2417,共14页
Combining refined composite multiscale fuzzy entropy(RCMFE)and support vector machine(SVM)with particle swarm optimization(PSO)for diagnosing roller bearing faults is proposed in this paper.Compared with refined compo... Combining refined composite multiscale fuzzy entropy(RCMFE)and support vector machine(SVM)with particle swarm optimization(PSO)for diagnosing roller bearing faults is proposed in this paper.Compared with refined composite multiscale sample entropy(RCMSE)and multiscale fuzzy entropy(MFE),the smoothness of RCMFE is superior to that of those models.The corresponding comparison of smoothness and analysis of validity through decomposition accuracy are considered in the numerical experiments by considering the white and 1/f noise signals.Then RCMFE,RCMSE and MFE are developed to affect extraction by using different roller bearing vibration signals.Then the extracted RCMFE,RCMSE and MFE eigenvectors are regarded as the input of the PSO-SVM to diagnose the roller bearing fault.Finally,the results show that the smoothness of RCMFE is superior to that of RCMSE and MFE.Meanwhile,the fault classification accuracy is higher than that of RCMSE and MFE. 展开更多
关键词 refined composite multiscale fuzzy entropy roller bearings support vector machine fault diagnosis particle swarm optimization
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Identification of denatured and normal biological tissues based on compressed sensing and refined composite multi-scale fuzzy entropy during high intensity focused ultrasound treatment 被引量:4
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作者 Shang-Qu Yan Han Zhang +2 位作者 Bei Liu Hao Tang Sheng-You Qian 《Chinese Physics B》 SCIE EI CAS CSCD 2021年第2期601-607,共7页
In high intensity focused ultrasound(HIFU)treatment,it is crucial to accurately identify denatured and normal biological tissues.In this paper,a novel method based on compressed sensing(CS)and refined composite multi-... In high intensity focused ultrasound(HIFU)treatment,it is crucial to accurately identify denatured and normal biological tissues.In this paper,a novel method based on compressed sensing(CS)and refined composite multi-scale fuzzy entropy(RCMFE)is proposed.First,CS is used to denoise the HIFU echo signals.Then the multi-scale fuzzy entropy(MFE)and RCMFE of the denoised HIFU echo signals are calculated.This study analyzed 90 cases of HIFU echo signals,including 45 cases in normal status and 45 cases in denatured status,and the results show that although both MFE and RCMFE can be used to identify denatured tissues,the intra-class distance of RCMFE on each scale factor is smaller than MFE,and the inter-class distance is larger than MFE.Compared with MFE,RCMFE can calculate the complexity of the signal more accurately and improve the stability,compactness,and separability.When RCMFE is selected as the characteristic parameter,the RCMFE difference between denatured and normal biological tissues is more evident than that of MFE,which helps doctors evaluate the treatment effect more accurately.When the scale factor is selected as 16,the best distinguishing effect can be obtained. 展开更多
关键词 compressed sensing high intensity focused ultrasound(HIFU)echo signal multi-scale fuzzy entropy refined composite multi-scale fuzzy entropy
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Microstructure and mechanical properties of in situ(TiC+SiC)/FeCrCoNi high entropy alloy matrix composites 被引量:1
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作者 Yu-lu Li Yue Zhao +2 位作者 Lin Shen Hao Wu He-guo Zhu 《Journal of Iron and Steel Research International》 SCIE EI CAS CSCD 2021年第4期496-504,共9页
In situ(TiC+SiC)particles(5 vol.%and 10 vol.%,respectively)-reinforced FeCrCoNi high entropy alloy matrix composites were fabricated via vacuum inductive melting method,with equal volume fractions of TiC and SiC parti... In situ(TiC+SiC)particles(5 vol.%and 10 vol.%,respectively)-reinforced FeCrCoNi high entropy alloy matrix composites were fabricated via vacuum inductive melting method,with equal volume fractions of TiC and SiC particles.X-ray diffraction,scanning electron microscope and energy diffraction spectrum were employed to analyze the microstructure and composi-tion of the samples.The results manifested that the FeCrCoNi matrix is composed of FCC phase,and the in situ particles are homogeneously scattered in the matrix.The presence of reinforcements augmented the ultimate tensile strength from 452 to 783 MPa,and raised the yield strength from 162 to 466 MPa at room temperature,whereas the elongation to fracture was reduced from 70.6%to 28.6%.All the tensile fracture surfaces consisted of numerous tiny dimples,indicating that the composites exhibited ductile fracture.Furthermore,the enhancement of strength ascribes to a combination of thermal mis-match strengthening,load-bearing effect,grain refinement,Orowan strengthening and solid solution strengthening effect,which contribute about 58.0%,2.4%,12.3%,11.1%and 16.2%to the improvement of yield tensile strength,respectively. 展开更多
关键词 High entropy alloy matrix composite In situ reaction MICROSTRUCTURE Mechanical property Strengthening mechanism
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Microstructure and Corrosion Resistance of a Novel AlNiLa Lightweight Medium Entropy Amorphous Alloy Composites
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作者 ZHANG Shuyan ZHANG Zhibin +3 位作者 GAO Yangyang WANG Xin SHEN Baolong LIANG Xiubing 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2022年第6期1185-1191,共7页
A new type of lightweight AlNiLa medium entropy amorphous alloy composite ribbons(labled as MEAAC ribbons)were prepared by vacuum arc melting technology and high-speed single roller meltspinning method.The microstruct... A new type of lightweight AlNiLa medium entropy amorphous alloy composite ribbons(labled as MEAAC ribbons)were prepared by vacuum arc melting technology and high-speed single roller meltspinning method.The microstructure and thermal stability of MEAAC ribbons were examined using X-ray diffraction,differential scanning calorimeter,and scanning electron microscope.Meanwhile,the hardness and surface roughness of these ribbons were measured by Vickers microhardness tester and atomic force microscope.The potentiodynamic polarization curves and electrochemical impedance spectroscopy(EIS)were applied to investigate the corrosion behavior of these MEAAC ribbons in simulated seawater(3.5wt%NaCl corrosive solution)at room temperature.The results demonstrate that AlNiLa MEAAC ribbons in the as-received state are mainly composed of amorphous phase and intermetallic compounds.The hardness values of all melt-spun ribbons are above 310 HV_(0.1).With the increase of Al content,the linear polarization resistances of four various AlNiLa MEAAC ribbons are negligibly different numerically.It is also found that Al_(45)Ni_(27.5)La_(27.5) MEAAC ribbons have the most positive corrosion potential and the smallest corrosion current density at the same time;hence it may be a kind of potential material for metal surface protection in harsh ocean environment. 展开更多
关键词 medium entropy amorphous alloy composites rapid solidification MICROSTRUCTURE corrosion resistance thermal stability
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Effect of cooling rate upon the microstructure and mechanical properties of in-situ TiC reinforced high entropy alloy CoCrFeNi 被引量:8
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作者 Jifeng Zhang Ting Jia +2 位作者 Huan Qiu Heguo Zhu Zonghan Xie 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2020年第7期122-129,共8页
Three types of in-situ TiC(5 vol%,10 vol%and 15 vol%)reinforced high entropy alloy CoCrFeNi matrix composites were produced by vacuum induction smelting.The effect of two extreme cooling conditions(i.e.,slow cooling i... Three types of in-situ TiC(5 vol%,10 vol%and 15 vol%)reinforced high entropy alloy CoCrFeNi matrix composites were produced by vacuum induction smelting.The effect of two extreme cooling conditions(i.e.,slow cooling in fu rnace and rapid cooling in copper crucible)upon the microstructure and mechanical properties was examined.In the case of slow cooling in the furnace,TiC was found to form mostly along the grain boundaries for the 5 vol%samples.With the increase of TiC reinforcements,fibrous TiC appeared and extended into the matrix,leading to an increase in hardness.The ultimate tensile strength of the composites shows a marked variation with increasing TiC content;that is,425.6 MPa(matrix),372.8 MPa(5 vol%),550.4 MPa(10 vol%)and 334.3 MPa(15 vol%),while the elongation-to-failure(i.e.,ductility)decreases.The fracture pattern was found to transit from the ductile to cleavage fracture,as the TiC content increased.When the samples cooled rapidly in copper crucible,the TiC particles formed both along the grain boundaries and within the grains.With the increase of TiC volume fraction,both the hardness and ultimate tensile strength of the resulting composites improved steadily while the elongation-to-failure declined.Therefore,the fast cooling can be used to drastically improve the strength of in-situ TiC reinforced CoCrFeNi.For example,for the 15 vol%TiC/CoCrFeNi composite cooled in the copper crucible,the hardness and ultimate tensile strength can reach as high as 595 HV and 941.7 MPa,respectively. 展开更多
关键词 High entropy alloy matrix composites Cooling rate MICROSTRUCTURE Mechanical properties
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Effect of vanadium content on microstructure and properties of in situ TiC reinforced V_(x)FeCoNiCu multi-principal-element alloy matrix composites
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作者 Chun-lei Tu Xiao-dong Sun +2 位作者 Jie Li He-guo Zhu Xiang-dong Li 《Journal of Iron and Steel Research International》 SCIE EI CSCD 2021年第11期1471-1480,共10页
V_(x)FeCoNiCu high entropy alloy matrix composites reinforced by in situ TiC particles(10 vol.%),i.e.,V_(x)FeCoNiCu/TiC composites,were fabricated from V–Fe–Co–Ni–Cu–Ti–C system using vacuum inductive melting me... V_(x)FeCoNiCu high entropy alloy matrix composites reinforced by in situ TiC particles(10 vol.%),i.e.,V_(x)FeCoNiCu/TiC composites,were fabricated from V–Fe–Co–Ni–Cu–Ti–C system using vacuum inductive melting method.With the content of vanadium increasing,the size of TiC particles decreased gradually.Meanwhile,vanadium agglomeration occurred slightly.The reaction mechanism of the mixed powder(Fe,V,Ti and C)and the mechanical properties of obtaining V_(x)FeCoNiCu/TiC composites were studied.It was found that three reactions occurred(Fe-Ti-FeTi-Fe_(2)Ti,FeTi-Fe_(2)Ti-Fe-Ti and Ti-C-TiC)in the heating process.The apparent activation energy for these three reactions was calculated and found to be 26.4,698.3 and 1879.0 kJ/mol,respectively.At room temperature,tensile strength and elongation increased first and then decreased with the increase in vanadium content and the microhardness increased gradually.The maximum tensile strength of the composites was determined to be 666 MPa,representing a 17.7%increase over that of FeCoNiCu/TiC high entropy alloy composites. 展开更多
关键词 High entropy alloy matrix composite Vacuum inductive melting Reaction mechanism Apparent activation energy Tensile strength
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Revisiting the relationship between composite multiscale entropy and THz optical parameters with exterior product
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作者 Haishun Liu Zhenwei Zhang +1 位作者 Meiyan Liang Cunlin Zhang 《Chinese Optics Letters》 SCIE EI CAS CSCD 2022年第6期66-71,共6页
With the framework of exterior product,we investigate the relationship between composite multiscale entropy[CMSE]and refractive index and absorption coefficient by reanalyzing six concentrations of bovine serum albumi... With the framework of exterior product,we investigate the relationship between composite multiscale entropy[CMSE]and refractive index and absorption coefficient by reanalyzing six concentrations of bovine serum albumin aqueous solutions from the published work.Two bivectors are constructed by CMSE and its square by the refractive index and absorption coefficient under vectorization.The desirable linear behaviors can be captured,not only between the defined two bivectors in normalized magnitudes,but also between the normalized magnitude of bivectors pertinent to CMSE and the magnitude of a single vector on the refractive index or absorption coefficient,with the processing of optimum selection.Besides that,the relationship between the coefficients of two bivectors is also considered.The results reveal that plenty of sound linear behaviors can be found and also suggest the scale of 15,16 and frequency of 0.2,0.21 THz are prominent for those linear behaviors.This work provides a new insight into the correlation between terahertz[THz]time and frequency domain information. 展开更多
关键词 bivector refractive index absorption coefficient TERAHERTZ composite multiscale entropy linear behavior
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Seasonal Short-Term Load Forecasting for Power Systems Based on Modal Decomposition and Feature-Fusion Multi-Algorithm Hybrid Neural Network Model
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作者 Jiachang Liu Zhengwei Huang +2 位作者 Junfeng Xiang Lu Liu Manlin Hu 《Energy Engineering》 EI 2024年第11期3461-3486,共26页
To enhance the refinement of load decomposition in power systems and fully leverage seasonal change information to further improve prediction performance,this paper proposes a seasonal short-termload combination predi... To enhance the refinement of load decomposition in power systems and fully leverage seasonal change information to further improve prediction performance,this paper proposes a seasonal short-termload combination prediction model based on modal decomposition and a feature-fusion multi-algorithm hybrid neural network model.Specifically,the characteristics of load components are analyzed for different seasons,and the corresponding models are established.First,the improved complete ensemble empirical modal decomposition with adaptive noise(ICEEMDAN)method is employed to decompose the system load for all four seasons,and the new sequence is obtained through reconstruction based on the refined composite multiscale fuzzy entropy of each decomposition component.Second,the correlation between different decomposition components and different features is measured through the max-relevance and min-redundancy method to filter out the subset of features with strong correlation and low redundancy.Finally,different components of the load in different seasons are predicted separately using a bidirectional long-short-term memory network model based on a Bayesian optimization algorithm,with a prediction resolution of 15 min,and the predicted values are accumulated to obtain the final results.According to the experimental findings,the proposed method can successfully balance prediction accuracy and prediction time while offering a higher level of prediction accuracy than the current prediction methods.The results demonstrate that the proposedmethod can effectively address the load power variation induced by seasonal differences in different regions. 展开更多
关键词 Short-term load forecasting seasonal characteristics refined composite multiscale fuzzy entropy(RCMFE) max-relevance and min-redundancy(mRMR) bidirectional long short-term memory(BiLSTM) hyperparameter search
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Superior wear performance of CoCrNi matrix composite reinforced with quasi-continuously networked graphene nanosheets and in-situ carbide
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作者 Wenting Ye Mingda Xie +5 位作者 Qing Zhou Biao Chen Yixue Li Lei Jia Haifeng Wang Weimin Liu 《Friction》 2025年第8期73-86,共14页
The biological materials evolved in nature generally exhibit interpenetrating network structures,which may offer useful inspiration for the architectural design of wear-resistant composites.Here,a strategy for designi... The biological materials evolved in nature generally exhibit interpenetrating network structures,which may offer useful inspiration for the architectural design of wear-resistant composites.Here,a strategy for designing self-lubricating medium entropy alloy(MEA)composites with high strength and excellent anti-wear performance was proposed through quasi-continuously networked in-situ carbides and graphene nanosheets.The discontinuous coating of graphene on the MEA powder surface inhibits continuous metallurgy bonding of the MEA powders during sintering,generating the typical quasi-continuously networked architecture.A good combination of mechanical properties with high fracture strength over 2 GPa and large compressive plasticity over 30%benefits from metallurgy bonding that prevents crack initiation and extension.The wear rate of an order of 10^(−6) m^(3)·N^(−1)·m^(−1) ascribing to an amorphous-crystalline nanocomposite surface,tribo-film induced by graphene,as well as the gradient worn subsurface during friction was achieved by the MEA composite,which is an order of magnitude lower than the unreinforced MEA matrix. 展开更多
关键词 in-situ carbide tribological behavior medium entropy alloy matrix composite graphene
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Decreasing complexity of glucose time series derived from continuous glucose monitoring is correlated with deteriorating glucose regulation 被引量:4
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作者 Cheng Li Xiaojing Ma +7 位作者 Jingyi Lu Rui Tao Xia Yu Yifei Mo Wei Lu Yuqian Bao Jian Zhou Weiping Jia 《Frontiers of Medicine》 SCIE CSCD 2023年第1期68-74,共7页
Most information used to evaluate diabetic statuses is collected at a special time-point,such as taking fasting plasma glucose test and providing a limited view of individual’s health and disease risk.As a new parame... Most information used to evaluate diabetic statuses is collected at a special time-point,such as taking fasting plasma glucose test and providing a limited view of individual’s health and disease risk.As a new parameter for continuously evaluating personal clinical statuses,the newly developed technique“continuous glucose monitoring”(CGM)can characterize glucose dynamics.By calculating the complexity of glucose time series index(CGI)with refined composite multi-scale entropy analysis of the CGM data,the study showed for the first time that the complexity of glucose time series in subjects decreased gradually from normal glucose tolerance to impaired glucose regulation and then to type 2 diabetes(P for trend<0.01).Furthermore,CGI was significantly associated with various parameters such as insulin sensitivity/secretion(all P<0.01),and multiple linear stepwise regression showed that the disposition index,which reflectsβ-cell function after adjusting for insulin sensitivity,was the only independent factor correlated with CGI(P<0.01).Our findings indicate that the CGI derived from the CGM data may serve as a novel marker to evaluate glucose homeostasis. 展开更多
关键词 complexity of glucose time series continuous glucose monitoring impaired glucose regulation insulin secretion and sensitivity refined composite multi-scale entropy
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