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Functionality evaluation of system of systems architecture based on extended influence diagrams 被引量:1
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作者 ZHANG Mengmeng CHEN Honghui +2 位作者 ZHANG Xiaoxue LUO Aimin LIU Junxian 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2018年第3期510-518,共9页
System of systems architecture(SoSA) has received increasing emphasis by scholars since Zachman ignited its flame in 1987. Given its complexity and abstractness, it is critical to validate and evaluate SoSA to ensur... System of systems architecture(SoSA) has received increasing emphasis by scholars since Zachman ignited its flame in 1987. Given its complexity and abstractness, it is critical to validate and evaluate SoSA to ensure requirements have been met.Multiple qualities are discussed in the literature of SoSA evaluation, while research on functionality is scarce. In order to assess SoSA functionality, an extended influence diagram(EID) is developed in this paper. Meanwhile, a simulation method is proposed to elicit the conditional probabilities in EID through designing and executing SoSA. An illustrative anti-missile architecture case is introduced for EID development, architecture design, and simulation. 展开更多
关键词 system of systems architecture(SoSA) functionality evaluation extended influence diagram(EID) anti-missile architecture SIMULATION
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Dynamic Stability Analysis of Linear Time-varying Systems via an Extended Modal Identification Approach 被引量:2
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作者 Zhisai MA Li LIU +3 位作者 Sida ZHOU Frank NAETS Ward HEYLEN Wim DESMET 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2017年第2期459-471,共13页
The problem of linear time-varying(LTV) system modal analysis is considered based on time-dependent state space representations, as classical modal analysis of linear time-invariant systems and current LTV system mo... The problem of linear time-varying(LTV) system modal analysis is considered based on time-dependent state space representations, as classical modal analysis of linear time-invariant systems and current LTV system modal analysis under the "frozen-time" assumption are not able to determine the dynamic stability of LTV systems. Time-dependent state space representations of LTV systems are first introduced, and the corresponding modal analysis theories are subsequently presented via a stabilitypreserving state transformation. The time-varying modes of LTV systems are extended in terms of uniqueness, and are further interpreted to determine the system's stability. An extended modal identification is proposed to estimate the time-varying modes, consisting of the estimation of the state transition matrix via a subspace-based method and the extraction of the time-varying modes by the QR decomposition. The proposed approach is numerically validated by three numerical cases, and is experimentally validated by a coupled moving-mass simply supported beam exper- imental case. The proposed approach is capable of accurately estimating the time-varying modes, and provides anew way to determine the dynamic stability of LTV systems by using the estimated time-varying modes. 展开更多
关键词 Linear time·varying systems · extended modal identification · Dynamic stability analysis · Time·varying modes
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A novel extended Tsypkin criterion for discrete-time descriptor systems with ferromagnetic hysteresis nonlinear physical phenomenon
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作者 张化光 宋铮 张庆灵 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第12期126-134,共9页
This paper concerns the absolute stability problem of discrete-time descriptor systems with feedback connected ferromagnetic hysteresis nonlinearities. The ferromagnetic hysteresis model satisfies the passivity condit... This paper concerns the absolute stability problem of discrete-time descriptor systems with feedback connected ferromagnetic hysteresis nonlinearities. The ferromagnetic hysteresis model satisfies the passivity conditions of hysteresis operator, that is the input-output relation of the transformed operator is passive. The bound condition of the solution of the ferromagnetic hysteresis model is given. Through the framework of loop transformation, an augmented discrete-time descriptor system model is established for the stability analysis. A new extended Tsypkin criterion for the absolute stability of discrete-time descriptor systems with hysteresis is presented based on the linear matrix inequalities technique. A numerical example is given to illustrate the effectiveness of the extended criterion. 展开更多
关键词 ferromagnetic hysteresis nonlinearity discrete-time descriptor systems extended Tsypkin criterion
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Four new lanostane triterpenoids featuring extendedπ-conjugated systems from the stems of Kadsura coccinea
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作者 Qi-Qi Zhang Kun Hu +1 位作者 Han-Dong Sun Pema-Tenzin Puno 《Natural Products and Bioprospecting》 CSCD 2023年第1期607-614,共8页
Four new 14(13→12)-abeolanostane triterpenoids featuring extendedπ-conjugated systems,kadcoccitanes E-H(1-4),were obtained from the stems of Kadsura coccinea through using a HPLC−UV-guided approach.Their structural ... Four new 14(13→12)-abeolanostane triterpenoids featuring extendedπ-conjugated systems,kadcoccitanes E-H(1-4),were obtained from the stems of Kadsura coccinea through using a HPLC−UV-guided approach.Their structural and configurational determination was accomplished through extensive spectroscopic analysis coupled with quantum chemical calculations.Kadcoccitanes E-H were tested for their cytotoxic activities against five human tumor cell lines(HL-60,A-549,SMMC-7721,MDA-MB-231,SW-480)but none of them exhibited activities at the concentration 40μM. 展开更多
关键词 Kadsura coccinea Lanostane triterpenoids extendedπ-conjugated systems Quantum chemical calculation
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Hierarchical Modeling by Recursive Unsupervised Spectral Clustering and Network Extended Importance Measures to Analyze the Reliability Characteristics of Complex Network Systems 被引量:1
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作者 Yiping Fang Enrico Zio 《American Journal of Operations Research》 2013年第1期101-112,共12页
The complexity of large-scale network systems made of a large number of nonlinearly interconnected components is a restrictive facet for their modeling and analysis. In this paper, we propose a framework of hierarchic... The complexity of large-scale network systems made of a large number of nonlinearly interconnected components is a restrictive facet for their modeling and analysis. In this paper, we propose a framework of hierarchical modeling of a complex network system, based on a recursive unsupervised spectral clustering method. The hierarchical model serves the purpose of facilitating the management of complexity in the analysis of real-world critical infrastructures. We exemplify this by referring to the reliability analysis of the 380 kV Italian Power Transmission Network (IPTN). In this work of analysis, the classical component Importance Measures (IMs) of reliability theory have been extended to render them compatible and applicable to a complex distributed network system. By utilizing these extended IMs, the reliability properties of the IPTN system can be evaluated in the framework of the hierarchical system model, with the aim of providing risk managers with information on the risk/safety significance of system structures and components. 展开更多
关键词 COMPLEX NETWORK system Hierarchical Modeling Spectral Clustering extended IMPORTANCE Measure
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Optimal Maintenance Modeling for Systems with Multiple Non-Identical Units Using Extended DSSP Method
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作者 Xiaohong Zhang Jianchao Zeng 《American Journal of Operations Research》 2016年第4期275-295,共22页
In the optimal maintenance modeling, all possible maintenance activities and their corresponding probabilities play a key role in modeling. For a system with multiple non-identical units, its maintenance requirements ... In the optimal maintenance modeling, all possible maintenance activities and their corresponding probabilities play a key role in modeling. For a system with multiple non-identical units, its maintenance requirements are very complicated, and it is time-consuming, even omission may occur when enumerating them with various combinations of units and even with different maintenance actions for them. Deterioration state space partition (DSSP) method is an efficient approach to analyze all possible maintenance requirements at each maintenance decision point and deduce their corresponding probabilities for maintenance modeling of multi-unit systems. In this paper, an extended DSSP method is developed for systems with multiple non-identical units considering opportunistic, preventive and corrective maintenance activities for each unit. In this method, different maintenance types are distinguished in each maintenance requirement. A new representation of the possible maintenance requirements and their corresponding probabilities is derived according to the partition results based on the joint probability density function of the maintained system deterioration state. Furthermore, focusing on a two-unit system with a non-periodical inspected condition-based opportunistic preventive-maintenance strategy;a long-term average cost model is established using the proposed method to determine its optimal maintenance parameters jointly, in which “hard failure” and non-negligible maintenance time are considered. Numerical experiments indicate that the extended DSSP method is valid for opportunistic maintenance modeling of multi-unit systems. 展开更多
关键词 extended Deterioration State Space Partition (DSSP) Condition-Based Opportunistic Preventive-Maintenance Hard Failure Non-Negligible Maintenance Times Multi-Unit systems
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ARCHITECTURE OF MANUFACTURING EXECUTION SYSTEM IN THE EXTENDED ENTERPRISE 被引量:6
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作者 Song Haisheng College of Electronic and Mechanical Engineering, Hebei University of Science and Technology,Shijiazhuang 050054,China Wang Jiahai Zhang Shu Tongji University 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2002年第1期90-93,共4页
The extended enterprise is formed according to the philosophy of dispersednetworked manufacturing. Manufacturing execution system (MES) can close the information gap whichexists between device control system and produ... The extended enterprise is formed according to the philosophy of dispersednetworked manufacturing. Manufacturing execution system (MES) can close the information gap whichexists between device control system and production information management system. The functions andthe web-based architecture of the MES in the extended enterprise are introduced. Using thecooperating system models of object-oriented and distributed agents and CORBA, all objects keep touniform interface standards and are easily inserted to object request broker. The utilization ofdistributed MES in extended enterprise can adapt fast change of manufacturing environment andresource. It also can improve the independent management capability of manufacturing cell and theenterprise response capability to global economic competition. 展开更多
关键词 extended enterprise Manufacturing execution system Dispersed networkedmanufacturing AGENT
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Score System Study for Hand-Extended Noodle Quality Based on HMW-GS Index in Wheat Flour 被引量:5
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作者 KANG Zhi-yu WANG Jian-jun SHANG Xun-wu 《Agricultural Sciences in China》 CAS CSCD 2007年第3期304-310,共7页
Hand-extended noodle, a special kind of noodle, requires particular quality flour to make it. High molecular weight glutenin subunits (HMW-GS) in wheat are important protein subunits, which affect flour quality. To ... Hand-extended noodle, a special kind of noodle, requires particular quality flour to make it. High molecular weight glutenin subunits (HMW-GS) in wheat are important protein subunits, which affect flour quality. To improve breeding and selection efficiency of wheat varieties which are used in making hand-extended noodle, 100 spring wheat varieties were selected to study the importance of HMW-GS on noodle quality score indexes such as color, appearance, taste agreeability, toughness, stickiness, smoothness, taste, and total score, through methods of quantity theory and statistic evaluation. It was shown that the hand-extended noodle quality score of HMW-GS 1, 2°, N, 7, 7 + 8, 17 + 18, 22, 2 + 10, 2 + 11, 2+ 12, 5 + 10, and 10 was 5.40, 5.35, 0, 2.55, 2.56, 9.19, 0.05, 0.15, 1.49, 1.14, 10.00, and 5.14, respectively. The score system for hand-extended noodle quality based on HMW-GS index included eight multiple linear regression equations (R^2 〉 0.98). Hence, using the HMW-GS composition, the eight hand-extended noodle quality indexes would be forecasted exactly. Results indicated that ideal subunit compositions of HMW-GS for this special usage were composition 1, 17 + 18, 5 + 10, or composition 2°, 17 + 18, 5 + 10. This standard could be used on variety selection in the early generation of breeding crosses. HMW-GS 2 + 10, 2 + 11, and 2 + 12 were the least desirable subunits for hand-extended noodle, which should be avoided in wheat variety selection aimed for hand-extended noodle flour use. 展开更多
关键词 WHEAT HMW-GS hand-extended noodle score index score system
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Noether's theorem for non-conservative Hamilton system based on El-Nabulsi dynamical model extended by periodic laws 被引量:5
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作者 龙梓轩 张毅 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第11期359-367,共9页
This paper focuses on the Noether symmetries and the conserved quantities for both holonomic and nonholonomic systems based on a new non-conservative dynamical model introduced by E1-Nabulsi. First, the E1-Nabulsi dyn... This paper focuses on the Noether symmetries and the conserved quantities for both holonomic and nonholonomic systems based on a new non-conservative dynamical model introduced by E1-Nabulsi. First, the E1-Nabulsi dynamical model which is based on a fractional integral extended by periodic laws is introduced, and E1-Nabulsi-Hamilton's canoni- cal equations for non-conservative Hamilton system with holonomic or nonholonomic constraints are established. Second, the definitions and criteria of E1-Nabulsi-Noether symmetrical transformations and quasi-symmetrical transformations are presented in terms of the invariance of E1-Nabulsi-Hamilton action under the infinitesimal transformations of the group. Fi- nally, Noether's theorems for the non-conservative Hamilton system under the E1-Nabulsi dynamical system are established, which reveal the relationship between the Noether symmetry and the conserved quantity of the system. 展开更多
关键词 Noether's theorem non-conservative Hamilton system E1-Nabulsi dynamical model fractionalintegral extended by periodic laws
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EXTENDED SYSTEM, BIFURCATION PROBLEM AND HIGH ORDER SINGULARITIES
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作者 胡国庆 李开泰 《Acta Mathematica Scientia》 SCIE CSCD 1995年第1期65-73,共9页
In this paper, we consider two extended systems. When using them for the two parameter bifurcation problems, the simple bifurcation point with regard to lambda on turn into the simple turning point with. regard to mu.... In this paper, we consider two extended systems. When using them for the two parameter bifurcation problems, the simple bifurcation point with regard to lambda on turn into the simple turning point with. regard to mu. Simple high orde bifurcation point is first studied without using the symmetry condition. 展开更多
关键词 2-PARAMETER NONLINEAR PROBLEMS extended systems BIFURCATION PROBLEM SIMPLE TURNING POINT SIMPLE HIGH ORDER BIFURCATION POINT
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Exact Traveling Wave Solutions for the System of Shallow Water Wave Equations and Modified Liouville Equation Using Extended Jacobian Elliptic Function Expansion Method 被引量:6
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作者 Emad H. M. Zahran Mostafa M. A. Khater 《American Journal of Computational Mathematics》 2014年第5期455-463,共9页
In this work, an extended Jacobian elliptic function expansion method is proposed for constructing the exact solutions of nonlinear evolution equations. The validity and reliability of the method are tested by its app... In this work, an extended Jacobian elliptic function expansion method is proposed for constructing the exact solutions of nonlinear evolution equations. The validity and reliability of the method are tested by its applications to the system of shallow water wave equations and modified Liouville equation which play an important role in mathematical physics. 展开更多
关键词 extended JACOBIAN Elliptic Function Expansion Method The system of Shallow Water WAVE Equations MODIFIED LIOUVILLE Equation Traveling WAVE SOLUTIONS SOLITARY WAVE SOLUTIONS
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Adaptive synchronization of a hyperchaotic L system based on extended passive control
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作者 傅桂元 李钟慎 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第6期101-105,共5页
This paper investigates the adaptive synchronization of hyperchaotic Lii systems based on the method of extended passive control. By combining the feedback control, the extended passive control method with two output ... This paper investigates the adaptive synchronization of hyperchaotic Lii systems based on the method of extended passive control. By combining the feedback control, the extended passive control method with two output variables is developed, which can synchronize hyperchaotic Lu systems asymptotically and globally more easily without knowing the bound of state of the hyperchaotic system. Adaptive laws are introduced to estimate the unknown parameters as well. Simulation results show the effectiveness and flexibility of the proposed control scheme. 展开更多
关键词 hyperchaotic Lu system SYNCHRONIZATION extended passive control adaptive control
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A kind of extended Korteweg-de Vries equation and solitary wave solutions for interfacial waves in a two-fluid system
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作者 杨红丽 宋金宝 +1 位作者 杨联贵 刘永军 《Chinese Physics B》 SCIE EI CAS CSCD 2007年第12期3589-3594,共6页
This paper considers interfacial waves propagating along the interface between a two-dimensional two-fluid with a flat bottom and a rigid upper boundary. There is a light fluid layer overlying a heavier one in the sys... This paper considers interfacial waves propagating along the interface between a two-dimensional two-fluid with a flat bottom and a rigid upper boundary. There is a light fluid layer overlying a heavier one in the system, and a small density difference exists between the two layers. It just focuses on the weakly non-linear small amplitude waves by introducing two small independent parameters: the nonlinearity ratio ε, represented by the ratio of amplitude to depth, and the dispersion ratio μ, represented by the square of the ratio of depth to wave length, which quantify the relative importance of nonlinearity and dispersion. It derives an extended KdV equation of the interfacial waves using the method adopted by Dullin et al in the study of the surface waves when considering the order up to O(μ^2). As expected, the equation derived from the present work includes, as special cases, those obtained by Dullin et al for surface waves when the surface tension is neglected. The equation derived using an alternative method here is the same as the equation presented by Choi and Camassa. Also it solves the equation by borrowing the method presented by Marchant used for surface waves, and obtains its asymptotic solitary wave solutions when the weakly nonlinear and weakly dispersive terms are balanced in the extended KdV equation. 展开更多
关键词 two-fluid system interracial waves extended KdV equation solitary wave solution
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Reliability Modelling and Analysis of Satellite Propulsion System Based on Reliability Block Diagram and Extended Object-Oriented Petri Net
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作者 周行 黄洪钟 《Journal of Donghua University(English Edition)》 EI CAS 2015年第6期1001-1005,共5页
Modern satellite propulsion systems are generally designed to fulfill multiphase-missions.Traditional reliability modelling methods have problems of inadequate depict capacity considering complex systems such as satel... Modern satellite propulsion systems are generally designed to fulfill multiphase-missions.Traditional reliability modelling methods have problems of inadequate depict capacity considering complex systems such as satellite propulsion system.An extended object-oriented Petri net(EOOPN)method was proposed to facilitate the reliability modelling of satellite propulsion system in the paper.The proposed method was specified for modelling of phased mission system,and it could be implemented by generating combination of Petri net(PN)principles and object-oriented(OO)programming.The effectiveness of the proposed method was demonstrated through the reliability modelling of a satellite propulsion system with EOOPN.The major advantage of the proposed method is that the dimension of net model can be reduced significantly,and phased mission system at system,phase,or component levels can be respectively depicted.Furthermore,the state-space explosion problem is solved by the proposed EOOPN model efficiently. 展开更多
关键词 satellite propulsion system extended object-oriented Petri net(EOOPN) object-oriented programming reliability modeling reliability analysis
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Extended Fisher-Kolmogorov系统的整体吸引子及其分形维数估计 被引量:3
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作者 罗宏 蒲志林 《四川师范大学学报(自然科学版)》 CAS CSCD 2004年第2期135-138,共4页
考虑在一般情况下ExtendedFisher Kolmogorov(EFK)系统的解的长时间行为,利用解的存在唯一性和在H和V1空间的吸收集的存在性,证明了该系统在L2中的整体吸引子的存在性,并给出了其整体吸引子的分形维数估计.
关键词 extended Fisher-Kolmogorov系统 整体吸引子 分形维数
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带Neumann边界条件的Extended Fisher-Kolmogorov系统的定态分歧 被引量:1
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作者 张强 曾艳 +1 位作者 李桂花 张黔川 《四川师范大学学报(自然科学版)》 CAS CSCD 北大核心 2014年第2期188-191,共4页
运用规范化的Lyapunov-Schmidt约化方法,得到了带Neumann边界条件的Extended FisherKolmogorov系统产生超临界和次临界分歧的完整判据,给出了分歧解的具体表达式,并进一步讨论了分歧解的正则性.
关键词 extended Fisher-Kolmogorov系统 NEUMANN边界 分歧 Lyapunov-Schmidt约化 正则性
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Extended Mendelsohn三元系大集的构造
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作者 王小哲 于兰香 《河北师范大学学报(自然科学版)》 CAS 北大核心 2006年第5期497-499,共3页
Mendelsohn三元系大集(LMTS)是一类有向设计的大集,它的存在性问题已完全解决.若在以上的设计中要求有序对(x,x)也出现,则称这样的设计为extended Mendelsohn三元系大集(LEMTS).给出了LEMTS的构造,从而完全解决了LEMTS的存在性问题.
关键词 Mendelsohn三元系大集 extended Mendelsohn三元系大集 循环三元组
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A Molecular Description of Superconductivity of Sulfur Hydride and Related Systems under High-Pressure Conditions 被引量:1
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作者 Henk M. Buck 《Open Journal of Physical Chemistry》 2017年第1期9-25,共17页
It has been shown that the recently discovered sulfur trihydride (H3S) can be considered as a superconductor with a transition temperature Tc of 203 Kelvin (K) at 155 GigaPascals (GPa). This is the highest Tc value re... It has been shown that the recently discovered sulfur trihydride (H3S) can be considered as a superconductor with a transition temperature Tc of 203 Kelvin (K) at 155 GigaPascals (GPa). This is the highest Tc value reported for any superconductor. The established superconductivity occurs via the formation of a molecular system with sulfur atoms arranged on a body-centered cubic lattice. It has been generally accepted that the high Tc value is the result of an efficient electron-phonon interaction. The responsible substance formed by H2S under high pressure, may be considered as a compound with H3S stoichiometry creating an impressive network with hydrogens. We will focus on the hydrogen bonding between sulfur and hydrogens demonstrating a symmetrical arrangement. The geometry of the individual radical compound in relation to corresponding systems will be discussed. Ab initio calculations based on a linear three-center two-, three- and four-electron type of bonding clearly visualized in combination with the dynamics of the Van’t Hoff concept, as described by us in various papers, give a good description of this exclusive network. We also discuss the superconductivity of related phosphorus hydrides and focus on the stability and geometrical differences with respect to the H3S system. These differences are significant, demonstrating the diversity in various structures in showing superconductivity. 展开更多
关键词 Super Conductivity High-Pressure Networks PROTON Bonding Configurational TRANSITIONS in extended systems
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Active Disturbance Rejection Control for Uncertain Nonlinear Systems With Sporadic Measurements 被引量:2
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作者 Kanghui He Chaoyang Dong Qing Wang 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2022年第5期893-906,共14页
This paper deals with the problem of active disturbance rejection control(ADRC)design for a class of uncertain nonlinear systems with sporadic measurements.A novel extended state observer(ESO)is designed in a cascade ... This paper deals with the problem of active disturbance rejection control(ADRC)design for a class of uncertain nonlinear systems with sporadic measurements.A novel extended state observer(ESO)is designed in a cascade form consisting of a continuous time estimator,a continuous observation error predictor,and a reset compensator.The proposed ESO estimates not only the system state but also the total uncertainty,which may include the effects of the external perturbation,the parametric uncertainty,and the unknown nonlinear dynamics.Such a reset compensator,whose state is reset to zero whenever a new measurement arrives,is used to calibrate the predictor.Due to the cascade structure,the resulting error dynamics system is presented in a non-hybrid form,and accordingly,analyzed in a general sampled-data system framework.Based on the output of the ESO,a continuous ADRC law is then developed.The convergence of the resulting closed-loop system is proved under given conditions.Two numerical simulations demonstrate the effectiveness of the proposed control method. 展开更多
关键词 Active disturbance rejection control(ADRC) extended state observer(ESO) sampled measurements uncertain nonlinear systems
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Full-order sliding mode control of uncertain chaos in a permanent magnet synchronous motor based on a fuzzy extended state observer 被引量:9
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作者 陈强 南余荣 +1 位作者 郑恒火 任雪梅 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第11期157-162,共6页
A full-order sliding mode control based on a fuzzy extended state observer is proposed to control the uncertain chaos in the permanent magnet synchronous motor. Through a simple coordinate transformation, the chaotic ... A full-order sliding mode control based on a fuzzy extended state observer is proposed to control the uncertain chaos in the permanent magnet synchronous motor. Through a simple coordinate transformation, the chaotic PMSM model is transformed into the Brunovsky canonical form, which is more suitable for the controller design. Based on the fuzzy control theory, a fuzzy extended state observer is developed to estimate the unknown states and uncertainties, and the restriction that all the system states should be completely measurable is avoided. Thereafter, a full-order sliding mode controller is designed to ensure the convergence of all system states without any chattering problem. Comparative simulations show the effectiveness and superior performance of the proposed control method. 展开更多
关键词 permanent magnet synchronous motor chaotic system sliding mode control fuzzy extended stateobserver
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