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Multiple Solutions for a Class of Singular Boundary Value Problems of Hadamard Fractional Differential Systems with p-Laplacian Operator
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作者 Chen Wang Yansheng Liu 《Journal of Applied Mathematics and Physics》 2024年第9期3114-3134,共21页
This paper discusses the existence and multiplicity of positive solutions for a class of singular boundary value problems of Hadamard fractional differential systems involving the p-Laplacian operator. First, for the ... This paper discusses the existence and multiplicity of positive solutions for a class of singular boundary value problems of Hadamard fractional differential systems involving the p-Laplacian operator. First, for the sake of overcoming the singularity, sequences of approximate solutions to the boundary value problem are obtained by applying the fixed point index theory on the cone. Next, it is demonstrated that these sequences of approximate solutions are uniformly bounded and equicontinuous. The main results are then established through the Ascoli-Arzelà theorem. Ultimately, an instance is worked out to test and verify the validity of the main results. 展开更多
关键词 multiple Solutions Fixed Point Index Theory Nonlinear Fractional Differential systems Hadamard Fractional Derivative
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Systemic lupus erythematosus in a 15-year-old female with multiple splenic nodules:A case report
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作者 Mi Il Kang Hyeok Chan Kwon 《World Journal of Clinical Cases》 SCIE 2024年第12期2128-2133,共6页
BACKGROUND Systemic lupus erythematosus(SLE)is a chronic inflammatory disease primarily affecting young females.SLE can invade any organ,and various forms of splenic invasion have been reported.Manifestations include ... BACKGROUND Systemic lupus erythematosus(SLE)is a chronic inflammatory disease primarily affecting young females.SLE can invade any organ,and various forms of splenic invasion have been reported.Manifestations include splenomegaly and splenic infarction,rupture,and calcification.The study encountered a rare case of splenic involvement,with nodules of various sizes without calcifications or ruptures.CASE SUMMARY A 15-year-old girl presented with arthralgia,weight loss,fever,increased levels of inflammatory markers,and positive antinuclear antibody test results.The patient was diagnosed with SLE.She was asymptomatic while taking steroids and hydroxychloroquine.Ten months after discharge,the patient developed a fever and abdominal pain.Lupus enteritis was suspected,and abdominopelvic computed tomography(AP-CT)was performed.There were no specific findings in the gastrointestinal tract,but multiple splenic nodules were observed.Infection or hemangioma was considered;however,no specific radiological findings were observed.A biopsy of the spleen was performed to determine the possibility of malignancy.The histological findings of the spleen included extensive periarteriolar necrosis with hematoxylin bodies and numerous karyorrhectic debris.Based on the biopsy results,the patient was diagnosed with an SLE flare-up and was maintained on high-dose steroids and immunosuppressants.CONCLUSION As disease activity increased,multiple nodules in the spleen that were previously unseen were observed using AP-CT and histologically confirmed.Spleen invasion by SLE can appear in multiple nodular forms and patterns.Therefore,physicians should consider these findings when differentiating these nodules from infections and malignancies. 展开更多
关键词 multiple nodules Spleen SPLENECTOMY systemic lupus erythematosus Differential diagnosis Case report
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Carbon efficiency evaluation method for urban energy system with multiple energy complementary
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作者 Xianan Jiao Jiekang Wu +1 位作者 Yunshou Mao Mengxuan Yan 《Global Energy Interconnection》 EI CSCD 2024年第2期142-154,共13页
Urban energy systems(UESs)play a pivotal role in the consumption of clean energy and the promotion of energy cascade utilization.In the context of the construction and operation strategy of UESs with multiple compleme... Urban energy systems(UESs)play a pivotal role in the consumption of clean energy and the promotion of energy cascade utilization.In the context of the construction and operation strategy of UESs with multiple complementary energy resources,a comprehensive assessment of the energy efficiency is of paramount importance.First,a multi-dimensional evaluation system with four primary indexes of energy utilization,environmental protection,system operation,and economic efficiency and 21 secondary indexes is constructed to comprehensively portray the UES.Considering that the evaluation system may contain a large number of indexes and that there is overlapping information among them,an energy efficiency evaluation method based on data processing,dimensionality reduction,integration of combined weights,and gray correlation analysis is proposed.This method can effectively reduce the number of calculations and improve the accuracy of energy efficiency assessments.Third,a demonstration project for a UES in China is presented.The energy efficiency of each scenario is assessed using six operational scenarios.The results show that Scenario 5,in which parks operate independently and investors build shared energy-storage equipment,has the best results and is best suited for green and low-carbon development.The results of the comparative assessment methods show that the proposed method provides a good energy efficiency assessment.This study provides a reference for the optimal planning,construction,and operation of UESs with multiple energy sources. 展开更多
关键词 Urban energy systems(UESs) multiple energy complementary system Carbon efficiency evaluation Data downscaling Subjective and objective weight Gray correlation analysis
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Refined Jensen-Based Multiple Integral Inequality and Its Application to Stability of Time-Delay Systems 被引量:5
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作者 Jidong Wang Zhanshan Wang +1 位作者 Sanbo Ding Huaguang Zhang 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2018年第3期758-764,共7页
This paper investigates the stability of time-delay systems via a multiple integral approach. Based on the refined Jensen-based inequality, a novel multiple integral inequality is proposed. Applying the multiple integ... This paper investigates the stability of time-delay systems via a multiple integral approach. Based on the refined Jensen-based inequality, a novel multiple integral inequality is proposed. Applying the multiple integral inequality to estimate the derivative of Lyapunov-Krasovskii functional(LKF) with multiple integral terms, a novel stability condition is formulated for the linear time-delay systems. Two numerical examples are employed to demonstrate the improvements of our results. 展开更多
关键词 multiple integral approach refined Jensen-based multiple integral inequality(RJMII) stability analysis time-delay systems
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TWO ALGORITHMS FOR SYMMETRIC LINEAR SYSTEMS WITH MULTIPLE RIGHT-HAND SIDES 被引量:4
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作者 戴华 《Numerical Mathematics A Journal of Chinese Universities(English Series)》 SCIE 2000年第1期91-110,共20页
In this paper, we investigate the block Lanczos algorithm for solving large sparse symmetric linear systems with multiple right-hand sides, and show how to incorporate deflation to drop converged linear systems using ... In this paper, we investigate the block Lanczos algorithm for solving large sparse symmetric linear systems with multiple right-hand sides, and show how to incorporate deflation to drop converged linear systems using a natural convergence criterion, and present an adaptive block Lanczos algorithm. We propose also a block version of Paige and Saunders’ MINRES method for iterative solution of symmetric linear systems, and describe important implementation details. We establish a relationship between the block Lanczos algorithm and block MINRES algorithm, and compare the numerical performance of the Lanczos algorithm and MINRES method for symmetric linear systems applied to a sequence of right hand sides with that of the block Lanczos algorithm and block MINRES algorithm for multiple linear systems simultaneously.[WT5,5”HZ] 展开更多
关键词 SYMMETRIC matrices multiple LINEAR systems BLOCK LANCZOS algorithm BLOCK MINRES method.
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Multiple Periodic Solutions for Some Classes of First-Order Hamiltonian Systems 被引量:6
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作者 Mohsen Timoumi 《Applied Mathematics》 2011年第7期846-853,共8页
Considering a decomposition R2N=A⊕B of R2N , we prove in this work, the existence of at least (1+dimA) geometrically distinct periodic solutions for the first-order Hamiltonian system Jx'(t)+H'(t,x(t))+e(t)=0... Considering a decomposition R2N=A⊕B of R2N , we prove in this work, the existence of at least (1+dimA) geometrically distinct periodic solutions for the first-order Hamiltonian system Jx'(t)+H'(t,x(t))+e(t)=0 when the Hamiltonian H(t,u+v) is periodic in (t,u) and its growth at infinity in v is at most like or faster than |v|a, 0≤ae is a forcing term. For the proof, we use the Least Action Principle and a Generalized Saddle Point Theorem. 展开更多
关键词 HAMILTONIAN systems Partial NONLINEARITY multiple PERIODIC Solutions Critical Point Theory
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Exponential Stability of Large-Scale Non-Linear Systems with Multiple The Delays
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作者 解三名 吴叶军 吴沧浦 《Journal of Beijing Institute of Technology》 EI CAS 1995年第1期41+36-41,共7页
The problem of stabilizing a class of large-scale non-linear multiple delay systems is considered.The complicated system is decomposed into several subsystems; each function of them is expressed by a set of components... The problem of stabilizing a class of large-scale non-linear multiple delay systems is considered.The complicated system is decomposed into several subsystems; each function of them is expressed by a set of components of the overall state vector,with interconnections between them, and the subsystems are coupled by the delayed state. In this paper, a method is devised to be a suitable choice of state feedback controls of every subsystems, moreover, it is proved that the large-scale system is exponential stable. 展开更多
关键词 large-scale systems/exponential stability multiple delay systems
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Stability criteria for linear systems with multiple time-varying delays 被引量:1
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作者 Bugong XU(Laboratory of Real-Time Control Through Internet and Fieldbuses, College of Automation Science and Engineering, South China University of Technology, Guangzhou Guangdong 510640, China) 《控制理论与应用(英文版)》 EI 2003年第1期65-69,共5页
New delay-independent and delay-dependent stability criteria for linear systems with multiple time-varying delays are established by using the time-domain method. The results are derived based on a new-type stability ... New delay-independent and delay-dependent stability criteria for linear systems with multiple time-varying delays are established by using the time-domain method. The results are derived based on a new-type stability theorem for general retarded dynamical systems and new analysis techniques developed in the author's previous work. Unlike some results in the literature, all of the established results do not depend on the derivative of time-varying delays. Therefore, they are suitable for the case with very fast time-varying delays. In addition, some remarks are also given to explain the obtained results and to point out the limitations of the previous results in the literature. Keywords Stability - Delay-independent criteria - Delay-dependent criteria - Linear time-delay systems - Multiple time-varying delays This work was supported by NSFC Key-Project (No. 60334010) and Guangdong Province Natural Science Foundation of China (No. 31406). 展开更多
关键词 STABILITY Delay-independent criteria Delay-dependent criteria Linear time-delay systems multiple time-varying delays
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Dynamic Consensus of High-order Multi-agent Systems and Its Application in the Motion Control of Multiple Mobile Robots 被引量:3
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作者 Zhong-Qiang Wu Yang Wang 《International Journal of Automation and computing》 EI 2012年第1期54-62,共9页
In this paper, the leader-following consensus problem for multi-agent linear dynamic systems is considered. All agents and leader have identical multi-input multi-output (MIMO) linear dynamics that can be of any ord... In this paper, the leader-following consensus problem for multi-agent linear dynamic systems is considered. All agents and leader have identical multi-input multi-output (MIMO) linear dynamics that can be of any order, and only the output information of each agent is delivered throughout the communication network. When the interaction topology is fixed, the leader-following consensus is attained by Ho~ dynamic output feedback control, and the sufficient condition of robust controllers is equal to the solvability of linear matrix inequality (LMI). The whole analysis is based on spectral decomposition and an equivalent decoupled structure achieved, and the stability of the system is proved. Finally, we extended the theoretical results to the case that the interaction topology is switching. The simulation results for multiple mobile robots show the effectiveness of the devised methods. 展开更多
关键词 Multi-agent systems consensus problem dynamic output feedback linear matrix inequality (LMI) multiple mobile robots.
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BLOCK BIDIAGONALIZATION METHODS FOR MULTIPLE NONSYMMETRIC LINEAR SYSTEMS 被引量:1
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作者 Dai Hua(戴华) 《Numerical Mathematics A Journal of Chinese Universities(English Series)》 SCIE 2001年第2期209-225,共17页
The symmetric linear system gives us many simplifications and a possibility to adapt the computations to the computer at hand in order to achieve better performance. The aim of this paper is to consider the block bidi... The symmetric linear system gives us many simplifications and a possibility to adapt the computations to the computer at hand in order to achieve better performance. The aim of this paper is to consider the block bidiagonalization methods derived from a symmetric augmented multiple linear systems and make a comparison with the block GMRES and block biconjugate gradient methods. 展开更多
关键词 NONSYMMETRIC LINEAR systems multiple right-hand sides BLOCK ITERATIVE methods.
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A NEW ANALYZING APPROACH TO MODELING SLOTTED MULTIPLE ACCESS SYSTEMS 被引量:1
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作者 Zhao Dongfeng (Department of Information and Electronic Science, Yunnan University, Kunming 650091) 《Journal of Electronics(China)》 1999年第1期44-50,共7页
In this paper, the analyzing approaches proposed by Zhao Dongfeng, et al.(1997) have been extensively studied. The average cyclic times of the slotted multiple access systems are analyzed by using the average cycle me... In this paper, the analyzing approaches proposed by Zhao Dongfeng, et al.(1997) have been extensively studied. The average cyclic times of the slotted multiple access systems are analyzed by using the average cycle method. Analytic formulae for mean values of a successful period and a colliding period and an idle period are derived. The upper bounds of the system throughput with capture effect and collision resolution are provided. Finally, the simulation results of the slotted multiple access channels are given. 展开更多
关键词 Slotted multiple Access systems(SMAS) AVERAGE CYCLE method CAPTURE effect COLLISION resolution
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Delay-dependent robust control for uncertain stochastic systems with Markovian switching and multiple delays 被引量:1
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作者 Xudong zhao Mingxiang Ling Qingshuang Zeng 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2010年第2期287-295,共9页
The exponential stability in mean square and stabiliza- tion problems for It& stochastic switched systems with multiple time-delays are investigated. The system possesses the norm- bounded uncertainties and Markovian... The exponential stability in mean square and stabiliza- tion problems for It& stochastic switched systems with multiple time-delays are investigated. The system possesses the norm- bounded uncertainties and Markovian jumping parameters. By using an effective descriptor model transformation of the system and applying Ito's differential formula and Moon's inequality for bounding cross terms, a new delay-dependent sufficient condi- tion is derived in terms of linear matrix inequalities, and its states feedback controller is designed. Numerical examples are given to illustrate the efficiency and less conservation of the results. 展开更多
关键词 stochastic systems Markovian jump time-delays lin- ear matrix inequalities.
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Multiple Solutions for a Class of Concave-Convex Quasilinear Elliptic Systems with Nonlinear Boundary Condition 被引量:1
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作者 Li Wang 《Applied Mathematics》 2013年第3期449-455,共7页
In this paper, a quasilinear elliptic system is investigated, which involves concave-convex nonlinearities and nonlinear boundary condition. By Nehari manifold, fibering method and analytic techniques, the existence o... In this paper, a quasilinear elliptic system is investigated, which involves concave-convex nonlinearities and nonlinear boundary condition. By Nehari manifold, fibering method and analytic techniques, the existence of multiple nontrivial nonnegative solutions to this equation is verified. 展开更多
关键词 multiple Solutions QUASILINEAR ELLIPTIC systems Nehari MANIFOLD Fibering Method
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Design and Optimization of Multiple Interconnected Utility Systems in An Integrated Refining and Petrochemical Complex 被引量:1
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作者 Bai Haobo Li Shiyu +1 位作者 Wang Xupeng Liu Chang 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS 2020年第4期126-136,共11页
In an integrated refining and petrochemical complex,a centralized utility system(CUS)is introduced to integrate the steam demands of production plants.Besides,two sub-utility systems(SUSs)located inside the alkene and... In an integrated refining and petrochemical complex,a centralized utility system(CUS)is introduced to integrate the steam demands of production plants.Besides,two sub-utility systems(SUSs)located inside the alkene and refinery plants,respectively,can satisfy the shaft demands.It is difficult to determine the steam production of the CUS because the steam demands of the alkene and refinery plants also depend on the design and operation of the SUSs.To explore the complicated interaction between the CUS and SUSs,we proposed a mixed-integer nonlinear programming(MINLP)model for the design and optimization of multiple interconnected utility systems to minimize the total annualized cost(TAC).An extended superstructure was suggested to contain multiple inter-plant connected steam pipe alternatives between the CUS and SUSs.A more accurate model of the complex steam turbine was proposed.Then the proposed MINLP framework is applied to a new integrated refining and petrochemical complex.Two scenarios are investigated in the case study to explore the effect of steam main temperatures on system configurations and operating parameters.By optimizing the main temperatures,a TAC of$2.7 million can be saved.Judging from the results of the two scenarios,the feasibility and effectiveness of the proposed framework for the design and optimization of multiple interconnected utility systems have been demonstrated. 展开更多
关键词 MINLP model multiple interconnected utility systems complex steam turbines steam main temperatures
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Novel sensitivity analysis method and dynamics optimization for multiple launch rocket systems 被引量:1
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作者 Tu Tianxiong Wang Guoping +1 位作者 Rui Xiaoting Miao Yunfei 《Journal of Southeast University(English Edition)》 EI CAS 2022年第1期15-19,共5页
This study establishes the launch dynamics method,sensitivity analysis method,and multiobjective dynamic optimization method for the dynamic simulation analysis of the multiple launch rocket system(MLRS)based on the R... This study establishes the launch dynamics method,sensitivity analysis method,and multiobjective dynamic optimization method for the dynamic simulation analysis of the multiple launch rocket system(MLRS)based on the Riccati transfer matrix method for multibody systems(RMSTMM),direct differentiation method(DDM),and genetic algorithm(GA),respectively.Results show that simulation results of the dynamic response agree well with test results.The sensitivity analysis method is highly programming,the matrix order is low,and the calculation time is much shorter than that of the Lagrange method.With the increase of system complexity,the advantage of a high computing speed becomes more evident.Structural parameters that have the greatest influence on the dynamic response include the connection stiffness between the pitching body and the rotating body,the connection stiffness between the rotating body and the vehicle body,and the connection stiffnesses among 14^(#),16^(#),and 17^(#)wheels and the ground,which are the optimization design variables.After optimization,angular velocity variances of the pitching body in the revolving and pitching directions are reduced by 97.84%and 95.22%,respectively. 展开更多
关键词 Riccati transfer matrix method for multibody systems multiple launch rocket system launch dynamics sensitivity analysis optimization design
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Delay-dependent Robust Stabilization for Uncertain Singular Systems with Multiple Input Delays 被引量:9
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作者 DU Zhao-Ping ZHANG Qing-Ling LIU Li-Li 《自动化学报》 EI CSCD 北大核心 2009年第2期162-167,共6页
关键词 物流管理信息系统 自动化系统 线性矩阵不等式 反馈控制器
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Delay-dependent observer-based stabilizing controller design for linear multiple state-delayed systems
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作者 Dejin WANG(Institute of Electronic Engineering, Heilongjiang University, Harbin Heilongjiang 150080, China) 《控制理论与应用(英文版)》 EI 2003年第1期101-104,共4页
This article concerns a coupled LMIs approach to delay-dependent observer-based output feedback stabilizing controller design for linear continuous-time systems with multiple state delays. The advantage of our propose... This article concerns a coupled LMIs approach to delay-dependent observer-based output feedback stabilizing controller design for linear continuous-time systems with multiple state delays. The advantage of our proposed delay-dependent coupled LMIs criterion lies in that: ( 1 ) it can optimize one of multiple time delays with others selected properly, and at the same time, the feedback-gain and observer-gain can be obtained, respectively. (2) it is less conservative than the existing delay-independent ones in the literature. Algorithm to solve the coupled LMIs is also given. Numerical examples illustrate the effectiveness of our method. Keywords Delay-dependent criterion - Time-delay system - Multiple time-delay - Observer-based controller - Linear matrixinequality (LMI) 展开更多
关键词 Delay-dependent criterion Time-delay system multiple time-delay Observer-based controller Linear matrixinequality (LMI)
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Multiple attractors and generalized synchronization in delayed Mackey-Glass systems
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作者 李栋 郑志刚 《Chinese Physics B》 SCIE EI CAS CSCD 2008年第11期4009-4013,共5页
Nonlinear dynamics of the time-delayed Mackey-Glass systems is explored. Coexistent multiple chaotic attractors are found. Attractors with double-scroll structures can be well classified in terms of different return t... Nonlinear dynamics of the time-delayed Mackey-Glass systems is explored. Coexistent multiple chaotic attractors are found. Attractors with double-scroll structures can be well classified in terms of different return times within one period of the delay time by constructing the Poincare section. Synchronizations of the drive-response Mackey-Glass oscillators are investigated. The critical coupling strength for the emergence of generalized synchronization against the delay time exhibits the interesting resonant behaviour. We reveal that stronger resonance effect may be observed when different attractors are applied to the drivers, i.e., more resonance peaks can be found. 展开更多
关键词 time-delayed Mackey-Glass system multiple chaotic attractors return numbers generalized synchronization
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Researted FOM for Multiple Shifted Linear Systems
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作者 李占稳 汪勇 顾桂定 《Journal of Shanghai University(English Edition)》 CAS 2005年第2期107-113,共7页
The seed method is used for solving multiple linear systems A (i)x (i) =b (i) for 1≤i≤s, where the coefficient matrix A (i) and the right-hand side b (i) are different in general. It is known that the CG meth... The seed method is used for solving multiple linear systems A (i)x (i) =b (i) for 1≤i≤s, where the coefficient matrix A (i) and the right-hand side b (i) are different in general. It is known that the CG method is an effective method for symmetric coefficient matrices A (i). In this paper, the FOM method is employed to solve multiple linear sy stems when coefficient matrices are non-symmetric matrices. One of the systems is selected as the seed system which generates a Krylov subspace, then the resi duals of other systems are projected onto the generated Krylov subspace to get t he approximate solutions for the unsolved ones. The whole process is repeated u ntil all the systems are solved. 展开更多
关键词 multiple linear systems seed method Krylov subspace FOM shifted systems.
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Adaptive switching control of a class of nonlinear systems based on mixed multiple models
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作者 曹奇敏 张艳霞 《Journal of Beijing Institute of Technology》 EI CAS 2012年第4期504-509,共6页
The transient behaviors of traditional adaptive control may be very poor in general. A practically feasible approach to improve the transient performances is the adoption of adaptive switc- hing control. For a typical... The transient behaviors of traditional adaptive control may be very poor in general. A practically feasible approach to improve the transient performances is the adoption of adaptive switc- hing control. For a typical class of nonlinear systems disturbed by random noises, mixed multiple models consisting of adaptive model and fixed models were considered to design the switching con- trol law. Under certain assumptions, the nonlinear system with the switching control law was proved rigorously to be stable and optimal A simulation example was provided to compare the performance of the switching control and the traditional adaptive control. 展开更多
关键词 adaptive control nonlinear systems switching control multiple models mixed models
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