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Model-driven full system dynamics estimation of PMSM-driven chain shell magazine 被引量:1
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作者 Kai Wei Longmiao Chen Quan Zou 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第9期147-156,共10页
Based on the system dynamic model, a full system dynamics estimation method is proposed for a chain shell magazine driven by a permanent magnet synchronous motor(PMSM). An adaptive extended state observer(AESO) is pro... Based on the system dynamic model, a full system dynamics estimation method is proposed for a chain shell magazine driven by a permanent magnet synchronous motor(PMSM). An adaptive extended state observer(AESO) is proposed to estimate the unmeasured states and disturbance, in which the model parameters are adjusted in real time. Theoretical analysis shows that the estimation errors of the disturbances and unmeasured states converge exponentially to zero, and the parameter estimation error can be obtained from the extended state. Then, based on the extended state of the AESO, a novel parameter estimation law is designed. Due to the convergence of AESO, the novel parameter estimation law is insensitive to controllers and excitation signal. Under persistent excitation(PE) condition, the estimated parameters will converge to a compact set around the actual parameter value. Without PE signal, the estimated parameters will converge to zero for the extended state. Simulation and experimental results show that the proposed method can accurately estimate the unmeasured states and disturbance of the chain shell magazine, and the estimated parameters will converge to the actual value without strictly continuous PE signals. 展开更多
关键词 Chain shell magazine Full system dynamics estimation Disturbance estimation Parameter estimation Adaptive extended state observer
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Preparation of entangledW states based on the cavity QED system
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作者 Ke Li Jun-Long Zhao 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第9期290-296,共7页
We present a qubit-loss-free(QLF)fusion scheme for generating large-scale atom W states in cavity quantum electrodynamics(QED)system.Compared to the most current fusion schemes which are conditioned on the case where ... We present a qubit-loss-free(QLF)fusion scheme for generating large-scale atom W states in cavity quantum electrodynamics(QED)system.Compared to the most current fusion schemes which are conditioned on the case where one particle can be extracted from each initial W state to the fusion process,our scheme will access one or two particles from each W state.Based on the atom–cavity-field detuned interaction,three jWin+m+t states can be generated from the jWin,jWim,and jWit states with the help of two auxiliary atoms,and three jWin+m+t+q states can be generated from jWin,jWim,jWit,and a jWiq state with the help of three auxiliary atoms.Comparing the numerical simulations of the resource cost of fusing three small-size W states based on the previous schemes,our fusion scheme seems to be more efficient.This QLF fusion scheme can be generalized to the case of fusing k different or identical particle W states.Furthermore,with no qubit loss,it greatly reduces the number of fusion steps and prepares W states with larger particle numbers. 展开更多
关键词 W state detuned interaction state fusion cavity quantum electrodynamics
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Retraction Note:Hydralazine Promotes Central Nervous System Recovery after Spinal Cord Injury by Suppressing Oxidative Stress and Inflammation through Macrophage Regulation
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作者 Xin QUAN Teng MA +4 位作者 Kai GUO Huan WANG Cai-yong YU Chu-chu QI Bao-qiang SONG 《Current Medical Science》 SCIE CAS 2024年第2期462-462,共1页
The Editor-in-Chief has retracted this article on the corresponding authors'request.The corresponding authors on behalf of all the authors stated that the data presented in this article does not belong to the name... The Editor-in-Chief has retracted this article on the corresponding authors'request.The corresponding authors on behalf of all the authors stated that the data presented in this article does not belong to the named authors,but belongs to Prof.Sheng-xi Wu and Prof.Wang Xi of the Department of Neurobiology of the Fourth Military Medical University,Xi'an,China. 展开更多
关键词 behalf stated China.
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Pure State Feedback Switching Control Based on the Online Estimated State for Stochastic Open Quantum Systems
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作者 Shuang Cong Zhixiang Dong 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第10期2166-2178,共13页
For the n-qubit stochastic open quantum systems,based on the Lyapunov stability theorem and LaSalle’s invariant set principle,a pure state switching control based on on-line estimated state feedback(short for OQST-SF... For the n-qubit stochastic open quantum systems,based on the Lyapunov stability theorem and LaSalle’s invariant set principle,a pure state switching control based on on-line estimated state feedback(short for OQST-SFC)is proposed to realize the state transition the pure state of the target state including eigenstate and superposition state.The proposed switching control consists of a constant control and a control law designed based on the Lyapunov method,in which the Lyapunov function is the state distance of the system.The constant control is used to drive the system state from an initial state to the convergence domain only containing the target state,and a Lyapunov-based control is used to make the state enter the convergence domain and then continue to converge to the target state.At the same time,the continuous weak measurement of quantum system and the quantum state tomography method based on the on-line alternating direction multiplier(QST-OADM)are used to obtain the system information and estimate the quantum state which is used as the input of the quantum system controller.Then,the pure state feedback switching control method based on the on-line estimated state feedback is realized in an n-qubit stochastic open quantum system.The complete derivation process of n-qubit QST-OADM algorithm is given;Through strict theoretical proof and analysis,the convergence conditions to ensure any initial state of the quantum system to converge the target pure state are given.The proposed control method is applied to a 2-qubit stochastic open quantum system for numerical simulation experiments.Four possible different position cases between the initial estimated state and that of the controlled system are studied and discussed,and the performances of the state transition under the corresponding cases are analyzed. 展开更多
关键词 Online state estimation state feedback control stochastic open quantum systems(OQST) switching control
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Hamiltonian system for the inhomogeneous plane elasticity of dodecagonal quasicrystal plates and its analytical solutions
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作者 孙志强 侯国林 +1 位作者 乔艳芬 刘金存 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第1期581-590,共10页
A Hamiltonian system is derived for the plane elasticity problem of two-dimensional dodecagonal quasicrystals by introducing the simple state function. By using symplectic elasticity approach, the analytic solutions o... A Hamiltonian system is derived for the plane elasticity problem of two-dimensional dodecagonal quasicrystals by introducing the simple state function. By using symplectic elasticity approach, the analytic solutions of the phonon and phason displacements are obtained further for the quasicrystal plates. In addition, the effectiveness of the approach is verified by comparison with the data of the finite integral transformation method. 展开更多
关键词 Hamiltonian system symplectic elasticity QUASICRYSTALS analytic solution state function
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THE LIMITING PROFILE OF SOLUTIONS FOR SEMILINEAR ELLIPTIC SYSTEMS WITH A SHRINKING SELF-FOCUSING CORE
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作者 金可 石影 谢华飞 《Acta Mathematica Scientia》 SCIE CSCD 2024年第2期583-608,共26页
In this paper,we consider the semilinear elliptic equation systems{△u+u=αQ_(n)(x)|u|^(α-2)|v|^(β)u in R^(N),-△v+v=βQ(x)|u|^(α)|v|^(β-2)v in R^(N),where N≥3,α,β>1,α+β<2^(*),2^(*)=2N/N-2 and Q_(n) are... In this paper,we consider the semilinear elliptic equation systems{△u+u=αQ_(n)(x)|u|^(α-2)|v|^(β)u in R^(N),-△v+v=βQ(x)|u|^(α)|v|^(β-2)v in R^(N),where N≥3,α,β>1,α+β<2^(*),2^(*)=2N/N-2 and Q_(n) are bounded given functions whose self-focusing cores{x∈R^(N)|Q_(n)(x)>0} shrink to a set with finitely many points as n→∞.Motivated by the work of Fang and Wang[13],we use variational methods to study the limiting profile of ground state solutions which are concentrated at one point of the set with finitely many points,and we build the localized concentrated bound state solutions for the above equation systems. 展开更多
关键词 Schrödinger system ground states solutions bound state solutions
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Numerical simulation for the initial state of avalanche in polydisperse particle systems
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作者 韩韧 李亭 +2 位作者 迟志鹏 杨晖 李然 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第2期405-412,共8页
Numerical simulation is employed to investigate the initial state of avalanche in polydisperse particle systems.Nucleation and propagation processes are illustrated for pentadisperse and triadisperse particle systems,... Numerical simulation is employed to investigate the initial state of avalanche in polydisperse particle systems.Nucleation and propagation processes are illustrated for pentadisperse and triadisperse particle systems,respectively.In these processes,particles involved in the avalanche grow slowly in the early stage and explosively in the later stage,which is clearly different from the continuous and steady growth trend in the monodisperse system.By examining the avalanche propagation,the number growth of particles involved in the avalanche and the slope of the number growth,the initial state can be divided into three stages:T1(nucleation stage),T2(propagation stage),T3(overall avalanche stage).We focus on the characteristics of the avalanche in the T2 stage,and find that propagation distances increase almost linearly in both axial and radial directions in polydisperse systems.We also consider the distribution characteristics of the average coordination number and average velocity for the moving particles.The results support that the polydisperse particle systems are more stable in the T2 stage. 展开更多
关键词 AVALANCHE initial state polydisperse particle systems PROPAGATION
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Valleytronic topological filters in silicene-like inner-edge systems
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作者 谢航 吕小龙 杨加恩 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第1期66-74,共9页
Inner edge state with spin and valley degrees of freedom is a promising candidate for designing a dissipationless device due to the topological protection. The central challenge for the application of the inner edge s... Inner edge state with spin and valley degrees of freedom is a promising candidate for designing a dissipationless device due to the topological protection. The central challenge for the application of the inner edge state is to generate and modulate the polarized currents. In this work, we discover a new mechanism to generate fully valley-and spin–valley-polarized current caused by the Bloch wavevector mismatch(BWM). Based on this mechanism, we design some serial-typed inner-edge filters. By using once of the BWM, the coincident states could be divided into transmitted and reflected modes, which can serve as a valley or spin–valley filter. In particular, while with twice of the BWM, the incident current is absolutely reflected to support an off state with a specified valley and spin, which is different from the gap effect.These findings give rise to a new platform for designing valleytronics and spin-valleytronics. 展开更多
关键词 topological insulator inner-edge state valley polarization spin polarization quantum transport
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Active Fault Tolerant Nonsingular Terminal Sliding Mode Control for Electromechanical System Based on Support Vector Machine
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作者 Jian Hu Zhengyin Yang Jianyong Yao 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2024年第3期189-203,共15页
Effective fault diagnosis and fault-tolerant control method for aeronautics electromechanical actuator is concerned in this paper.By borrowing the advantages of model-driven and data-driven methods,a fault tolerant no... Effective fault diagnosis and fault-tolerant control method for aeronautics electromechanical actuator is concerned in this paper.By borrowing the advantages of model-driven and data-driven methods,a fault tolerant nonsingular terminal sliding mode control method based on support vector machine(SVM)is proposed.A SVM is designed to estimate the fault by off-line learning from small sample data with solving convex quadratic programming method and is introduced into a high-gain observer,so as to improve the state estimation and fault detection accuracy when the fault occurs.The state estimation value of the observer is used for state reconfiguration.A novel nonsingular terminal sliding mode surface is designed,and Lyapunov theorem is used to derive a parameter adaptation law and a control law.It is guaranteed that the proposed controller can achieve asymptotical stability which is superior to many advanced fault-tolerant controllers.In addition,the parameter estimation also can help to diagnose the system faults because the faults can be reflected by the parameters variation.Extensive comparative simulation and experimental results illustrate the effectiveness and advancement of the proposed controller compared with several other main-stream controllers. 展开更多
关键词 Aeronautics electromechanical actuator Fault tolerant control Support vector machine State observer Parametric uncertainty
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Scientific exploration and hypotheses concerning the meridian system in traditional Chinese medicine
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作者 Wenchuan Qi Bin He +2 位作者 Qingxin Gu Yongming Li Fanrong Liang 《Acupuncture and Herbal Medicine》 2024年第3期283-289,共7页
The meridian theory is an important component of traditional Chinese medicine,playing a crucial role in disease diagnosis,treatment,and health preservation.Serving as the media for the effects of acupuncture,moxibusti... The meridian theory is an important component of traditional Chinese medicine,playing a crucial role in disease diagnosis,treatment,and health preservation.Serving as the media for the effects of acupuncture,moxibustion,herbal medicine,and acupressure massage,meridians exert undeniable impact on the human body.However,the essence of meridians remains a topic of debate.Recent research has primarily focused on their anatomical structures,leading to numerous hypotheses.Simultaneously,other researchers have approached this subject from an energetic perspective,discovering information interactions within the meridian system.These findings suggest that meridians possess both physical and information dimensions,indicating that a singular approach to their study is insufficient.To bridge this gap,a shift from purely structural research toward an exploration of the information aspects of meridians is necessary.By integrating this information approach with traditional meridian theory,it may be possible to develop a new,modernized meridian theory that is aligned with contemporary concepts,making it more accessible and applicable in clinical settings. 展开更多
关键词 COMMUNICATION Information state Meridian essence Physical state
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Approximate constructions of counterdiabatic driving with NMR quantum systems
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作者 Hui Zhou Xiaoli Dai +2 位作者 Jianpei Geng Yunlan Ji Xinhua Peng 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第9期83-91,共9页
Counterdiabatic driving (CD) offers a fast and robust route to manipulate quantum systems, which has widespreadapplications in quantum technologies. However, for higher-dimensional complex systems, the exact CD term i... Counterdiabatic driving (CD) offers a fast and robust route to manipulate quantum systems, which has widespreadapplications in quantum technologies. However, for higher-dimensional complex systems, the exact CD term involving thespectral properties of the system is difficult to calculate and generally takes a complicated form, impeding its experimentalrealization. Recently, many approximate methods have been proposed for designing CD passages in many-body systems. Inthis topical review, we focus on the CD formalism and briefly introduce several experimental constructions and applicationsof approximate CD driving in spin-chain models with nuclear magnetic resonance (NMR) systems. 展开更多
关键词 nuclear magnetic resonance quantum simulation quantum state engineering
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Optimizing near-carbon-free nuclear energy systems:advances in reactor operation digital twin through hybrid machine learning algorithms for parameter identification and state estimation
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作者 Li‑Zhan Hong He‑Lin Gong +3 位作者 Hong‑Jun Ji Jia‑Liang Lu Han Li Qing Li 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第8期177-203,共27页
Accurate and efficient online parameter identification and state estimation are crucial for leveraging digital twin simulations to optimize the operation of near-carbon-free nuclear energy systems.In previous studies,... Accurate and efficient online parameter identification and state estimation are crucial for leveraging digital twin simulations to optimize the operation of near-carbon-free nuclear energy systems.In previous studies,we developed a reactor operation digital twin(RODT).However,non-differentiabilities and discontinuities arise when employing machine learning-based surrogate forward models,challenging traditional gradient-based inverse methods and their variants.This study investigated deterministic and metaheuristic algorithms and developed hybrid algorithms to address these issues.An efficient modular RODT software framework that incorporates these methods into its post-evaluation module is presented for comprehensive comparison.The methods were rigorously assessed based on convergence profiles,stability with respect to noise,and computational performance.The numerical results show that the hybrid KNNLHS algorithm excels in real-time online applications,balancing accuracy and efficiency with a prediction error rate of only 1%and processing times of less than 0.1 s.Contrastingly,algorithms such as FSA,DE,and ADE,although slightly slower(approximately 1 s),demonstrated higher accuracy with a 0.3%relative L_2 error,which advances RODT methodologies to harness machine learning and system modeling for improved reactor monitoring,systematic diagnosis of off-normal events,and lifetime management strategies.The developed modular software and novel optimization methods presented offer pathways to realize the full potential of RODT for transforming energy engineering practices. 展开更多
关键词 Parameter identification State estimation Reactor operation digital twin Reduced order model Inverse problem
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Quantitative determination of the critical points of Mott metal–insulator transition in strongly correlated systems
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作者 牛月坤 倪煜 +4 位作者 王建利 陈雷鸣 邢晔 宋筠 冯世平 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第1期647-652,共6页
Mottness is at the heart of the essential physics in a strongly correlated system as many novel quantum phenomena occur in the metallic phase near the Mott metal–insulator transition. We investigate the Mott transiti... Mottness is at the heart of the essential physics in a strongly correlated system as many novel quantum phenomena occur in the metallic phase near the Mott metal–insulator transition. We investigate the Mott transition in a Hubbard model by using the dynamical mean-field theory and introduce the local quantum state fidelity to depict the Mott metal–insulator transition. The local quantum state fidelity provides a convenient approach to determining the critical point of the Mott transition. Additionally, it presents a consistent description of the two distinct forms of the Mott transition points. 展开更多
关键词 critical point metal–insulator transition local quantum state fidelity strongly correlated system quasiparticle coherent weight
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State Estimation Method for GNSS/INS/Visual Multi-sensor Fusion Based on Factor Graph Optimization for Unmanned System
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作者 ZHU Zekun YANG Zhong +2 位作者 XUE Bayang ZHANG Chi YANG Xin 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2024年第S01期43-51,共9页
With the development of unmanned driving technology,intelligent robots and drones,high-precision localization,navigation and state estimation technologies have also made great progress.Traditional global navigation sa... With the development of unmanned driving technology,intelligent robots and drones,high-precision localization,navigation and state estimation technologies have also made great progress.Traditional global navigation satellite system/inertial navigation system(GNSS/INS)integrated navigation systems can provide high-precision navigation information continuously.However,when this system is applied to indoor or GNSS-denied environments,such as outdoor substations with strong electromagnetic interference and complex dense spaces,it is often unable to obtain high-precision GNSS positioning data.The positioning and orientation errors will diverge and accumulate rapidly,which cannot meet the high-precision localization requirements in large-scale and long-distance navigation scenarios.This paper proposes a method of high-precision state estimation with fusion of GNSS/INS/Vision using a nonlinear optimizer factor graph optimization as the basis for multi-source optimization.Through the collected experimental data and simulation results,this system shows good performance in the indoor environment and the environment with partial GNSS signal loss. 展开更多
关键词 state estimation multi-sensor fusion combined navigation factor graph optimization complex environments
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Interface state-based bound states in continuum and below-continuum-resonance modes with high-Q factors in the rotational periodic system
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作者 杨嘉玲 史奥芊 +2 位作者 彭宇宸 彭鹏 刘建军 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第8期288-293,共6页
We have introduced a new approach to calculate the orbital angular momentum(OAM)of bound states in continuum(BICs)and below-continuum-resonance(BCR)modes in the rotational periodic system nested inside and outside by ... We have introduced a new approach to calculate the orbital angular momentum(OAM)of bound states in continuum(BICs)and below-continuum-resonance(BCR)modes in the rotational periodic system nested inside and outside by transforming the Bloch wave number from the translational periodic system.We extensively classify and study these BICs and BCR modes,which exhibit high-quality(high-Q)factors,in different regions relative to the interface of the system.These BICs and BCR modes with a high-Q factor have been studied in detail based on distinctive structural parameters and scattering theory.The outcomes of this research break the periodic limitation of interface state-based BICs,and realize more and higher symmetry interface state-based BICs and BCR modes.Moreover,we can control the region where light is captured by adjusting the frequency,and show that the Q factor of BICs is more closely related to the ordinal number of rings and the rotational symmetry number of the system. 展开更多
关键词 bound states in the continuum below continuum resonance modes high-quality factors
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Anomaly-Resistant Decentralized State Estimation Under Minimum Error Entropy With Fiducial Points for Wide-Area Power Systems
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作者 Bogang Qu Zidong Wang +2 位作者 Bo Shen Hongli Dong Hongjian Liu 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第1期74-87,共14页
This paper investigates the anomaly-resistant decentralized state estimation(SE) problem for a class of wide-area power systems which are divided into several non-overlapping areas connected through transmission lines... This paper investigates the anomaly-resistant decentralized state estimation(SE) problem for a class of wide-area power systems which are divided into several non-overlapping areas connected through transmission lines. Two classes of measurements(i.e., local measurements and edge measurements) are obtained, respectively, from the individual area and the transmission lines. A decentralized state estimator, whose performance is resistant against measurement with anomalies, is designed based on the minimum error entropy with fiducial points(MEEF) criterion. Specifically, 1) An augmented model, which incorporates the local prediction and local measurement, is developed by resorting to the unscented transformation approach and the statistical linearization approach;2) Using the augmented model, an MEEF-based cost function is designed that reflects the local prediction errors of the state and the measurement;and 3) The local estimate is first obtained by minimizing the MEEF-based cost function through a fixed-point iteration and then updated by using the edge measuring information. Finally, simulation experiments with three scenarios are carried out on the IEEE 14-bus system to illustrate the validity of the proposed anomaly-resistant decentralized SE scheme. 展开更多
关键词 Decentralized state estimation(SE) measurements with anomalies minimum error entropy unscented Kalman filter wide-area power systems
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A Health State Prediction Model Based on Belief Rule Base and LSTM for Complex Systems
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作者 Yu Zhao Zhijie Zhou +3 位作者 Hongdong Fan Xiaoxia Han JieWang Manlin Chen 《Intelligent Automation & Soft Computing》 2024年第1期73-91,共19页
In industrial production and engineering operations,the health state of complex systems is critical,and predicting it can ensure normal operation.Complex systems have many monitoring indicators,complex coupling struct... In industrial production and engineering operations,the health state of complex systems is critical,and predicting it can ensure normal operation.Complex systems have many monitoring indicators,complex coupling structures,non-linear and time-varying characteristics,so it is a challenge to establish a reliable prediction model.The belief rule base(BRB)can fuse observed data and expert knowledge to establish a nonlinear relationship between input and output and has well modeling capabilities.Since each indicator of the complex system can reflect the health state to some extent,the BRB is built based on the causal relationship between system indicators and the health state to achieve the prediction.A health state prediction model based on BRB and long short term memory for complex systems is proposed in this paper.Firstly,the LSTMis introduced to predict the trend of the indicators in the system.Secondly,the Density Peak Clustering(DPC)algorithmis used todetermine referential values of indicators for BRB,which effectively offset the lack of expert knowledge.Then,the predicted values and expert knowledge are fused to construct BRB to predict the health state of the systems by inference.Finally,the effectiveness of the model is verified by a case study of a certain vehicle hydraulic pump. 展开更多
关键词 Health state predicftion complex systems belief rule base expert knowledge LSTM density peak clustering
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Multi-Sensor Intelligent System for On-Line and Real-Time Moneitoring Tool Cutting State in FMS 被引量:1
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作者 徐春广 王信义 +1 位作者 邢济收 杨大勇 《Journal of Beijing Institute of Technology》 EI CAS 1997年第3期258-266,共9页
The principle and the constitution of an intelligent system for on-line and real-time montitoring tool cutting state were discussed and a synthetic sensors schedule combined a new type fluid acoustic emission sens... The principle and the constitution of an intelligent system for on-line and real-time montitoring tool cutting state were discussed and a synthetic sensors schedule combined a new type fluid acoustic emission sensor (AE) with motor current sensor was presented. The parallel communication between control system of machine tools, the monitoring intelligent system,and several decision-making systems for identifying tool cutting state was established It can auto - matically select the sensor way ,monitoring mode and identifying method in machining process- ing so as to build a successful and effective intelligent system for on -line and real-time moni- toring cutting tool states in FMS. 展开更多
关键词 tool cutting state on-line monitoring intelligent system acoustic emission sensor
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New approach of Kalman filter to nonlinear system 被引量:1
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作者 张卫明 张炎华 +1 位作者 钟山 杜刚 《Journal of Southeast University(English Edition)》 EI CAS 2005年第1期24-28,共5页
In order to achieve higher accuracy in nonlinear/non-Gaussian state estimation, this paper proposes a new unscented Kalman filter (UKF). It uses a deterministic sampling approach. We choose the unscented transformatio... In order to achieve higher accuracy in nonlinear/non-Gaussian state estimation, this paper proposes a new unscented Kalman filter (UKF). It uses a deterministic sampling approach. We choose the unscented transformation (UT) scaling parameters α=0.85, β=2, l=0 to construct 2n + 1 sigma points. These sigma points completely capture the mean and covariance of the Gaussian random variables of the nonlinear system Yi=F(Xi). Simulation results show that the posterior mean and covariance of the sigma points can achieve the accuracy of the third-order Taylor series expansion after having propagated through the true nonlinear system Yi=F(Xi). Extended Kalman filter (EKF) only can achieve the first-order accuracy. The computational complexity of UKF is the same level as that of EKF. UKF can yield better performance and higher accuracy than EKF. 展开更多
关键词 Nonlinear systems State estimation
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B-X and C-X Band Systems of CuCl Revisited: Laser-induced Fluorescence Study in 465-490 nm
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作者 王莉 甄军锋 +1 位作者 张群 陈旸 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2010年第3期249-251,I0001,共4页
We have reinvestigated the B-X and C-X band systems of CuCl by recording the laser- induced fluorescence excitation spectra in 20400-21800 cm^-1. The rotational analyses in Hund's case (a) revealed unambiguously a ... We have reinvestigated the B-X and C-X band systems of CuCl by recording the laser- induced fluorescence excitation spectra in 20400-21800 cm^-1. The rotational analyses in Hund's case (a) revealed unambiguously a singlet-to-singlet transition nature. The radiative lifetimes were measured to be 4.670 and 4.667 μs, respectively, which are much longer than that expected for a pure singlet of CuCl. This implies that the fluorescence mechanism in the B or C band systems lies in the mixing of the singlets (^1II and ^1E^+) and triplets (^3II0,1,2) and that the two excited states observed in our experiment might be the singlets that have been strongly "contaminated" by their triplet neighbors. 展开更多
关键词 CUCL B state C state Laser-induced fluorescence
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