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PERIODIC SYSTEMS WITH TIME DEPENDENT MAXIMAL MONOTONE OPERATORS
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作者 Zhenhai LIU Nikolaos S.PAPAGEORGIOU 《Acta Mathematica Scientia》 SCIE CSCD 2024年第4期1280-1300,共21页
We consider a first order periodic system in R^(N),involving a time dependent maximal monotone operator which need not have a full domain and a multivalued perturbation.We prove the existence theorems for both the con... We consider a first order periodic system in R^(N),involving a time dependent maximal monotone operator which need not have a full domain and a multivalued perturbation.We prove the existence theorems for both the convex and nonconvex problems.We also show the existence of extremal periodic solutions and provide a strong relaxation theorem.Finally,we provide an application to nonlinear periodic control systems. 展开更多
关键词 periodic boundary condition time-dependent maximal monotone operator convex and nonconvex problems extremal solutions strong relaxation
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Study on Independent Supervision Function of Design Assurance System
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作者 SUI Lijun MA Congyao WANG Jianyuan 《International Journal of Plant Engineering and Management》 2024年第3期185-192,共8页
The effective operation of a design assurance system cannot be achieved without the effective performance of the independent supervision function.As one of the core functions of the design assurance system,the purpose... The effective operation of a design assurance system cannot be achieved without the effective performance of the independent supervision function.As one of the core functions of the design assurance system,the purpose of the independent supervision function is to ensure that the system operates within the scope of procedures and manuals.At present,the function of independent supervision is a difficult and confusing issue for various original equipment manufacturers as well as suppliers,and there is an urgent requirement to put forward relevant requirements and form relevant methods.Based on the above mentioned objective,the basic requirements of the independent supervision function of design assurance system were studied,the problems and deficiencies in the organization,staffing,and methods existing in the current independent supervision function were analyzed,the improvement suggestions and measures for the performance of the independent supervision function from the aspects of the organization,staffing,procedures,and suppliers were put forward.The present work and conclusions provide guidance and direction for the effective operation of the design assurance system. 展开更多
关键词 design of assurance systems independent supervision functions system operation internal audits SUPPLIERS
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Three Dimensional Kinematics Analysis of the Independent Suspension Multibody System 被引量:2
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作者 陈欣 林逸 +1 位作者 孙大刚 白文辉 《Journal of Beijing Institute of Technology》 EI CAS 1997年第4期80-86,共7页
Based on the theory of multibody system dynamics, the spatial kinematics analysis of the Mcpherson independent suspension widely used in the car was carried out. A practical and simpler method was provided to reduce t... Based on the theory of multibody system dynamics, the spatial kinematics analysis of the Mcpherson independent suspension widely used in the car was carried out. A practical and simpler method was provided to reduce the number of the generalized coordinates and constraint functions. By solving the nonlinear equations, the motion of any points in the whole suspension and wheel system can be predicted, including the spatial changes of the wheel alignment parameters which are of great importance to the car performances. 展开更多
关键词 independent suspension three dimension kinematic analysis multibody system
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Maximal and total skew information for a two-qubit system using nonlinear interaction models 被引量:7
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作者 孙红贵 刘万芳 李春杰 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第9期37-43,共7页
Maximal and total skew information is studied. For symmetric pure states of two-qubit, they are closely related to the linear entropy, the concurrence, and the spin squeezing parameter. For a two-qubit system implemen... Maximal and total skew information is studied. For symmetric pure states of two-qubit, they are closely related to the linear entropy, the concurrence, and the spin squeezing parameter. For a two-qubit system implemented in three nonlinear interaction models with an external field, we give the exact state vectors and the expectation value (Sz) at any time t. Based on (Sz)2, we give the maximal and the total skew information and a condition in which the maximal and the total skew information can reach 1 and 2, respectively. 展开更多
关键词 maximal and total Wigner-Yanase skew information nonlinear interaction models two-qubit system
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Maximal and total skew information of three-qubit system obtained using nonlinear interaction models 被引量:6
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作者 Sun Hong-Gui Liu Wan-Fang +1 位作者 Zhang Li-Hua Li Chun-Jie 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第1期52-61,共10页
Both the maximal and the total skew information have been studied. For a three-qubit system implemented in three nonlinear interaction models, we give the exact state vector at any time t. Beused on this, we give the ... Both the maximal and the total skew information have been studied. For a three-qubit system implemented in three nonlinear interaction models, we give the exact state vector at any time t. Beused on this, we give the maximal and the total skew information. It is found that they have the same form and their evolution periods are dependent on the energy difference between the ground state and the second excited state in these models. The maximal skew information is always in the (Sx, Sv) plane. We give the condition for the occurrence of IGHZ}sy, in which they can reach the extreme values of 9/4 and 15/4, respectively. In three different decoherence channels, two kinds of information and the concurrence are calculated. We find that the phenomenon of the concurrence of sudden death occurs, but the above two kinds of information do not die suddenly. In the phase-damping channel, the two kinds of information will not be lost completely. 展开更多
关键词 maximal and total Wigner-Yanase skew information nonlinear interaction models three-qubit system three decoherenee channels
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Independent component analysis approach for fault diagnosis of condenser system in thermal power plant 被引量:6
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作者 Ajami Ali Daneshvar Mahdi 《Journal of Central South University》 SCIE EI CAS 2014年第1期242-251,共10页
A statistical signal processing technique was proposed and verified as independent component analysis(ICA) for fault detection and diagnosis of industrial systems without exact and detailed model.Actually,the aim is t... A statistical signal processing technique was proposed and verified as independent component analysis(ICA) for fault detection and diagnosis of industrial systems without exact and detailed model.Actually,the aim is to utilize system as a black box.The system studied is condenser system of one of MAPNA's power plants.At first,principal component analysis(PCA) approach was applied to reduce the dimensionality of the real acquired data set and to identify the essential and useful ones.Then,the fault sources were diagnosed by ICA technique.The results show that ICA approach is valid and effective for faults detection and diagnosis even in noisy states,and it can distinguish main factors of abnormality among many diverse parts of a power plant's condenser system.This selectivity problem is left unsolved in many plants,because the main factors often become unnoticed by fault expansion through other parts of the plants. 展开更多
关键词 CONDENSER fault detection and diagnosis independent component analysis independent component analysis (ICA) principal component analysis (PCA) thermal power plant
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Research on Vehicle Control Technology Using Four-Wheel Independent Steering System 被引量:5
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作者 陈思忠 舒进 杨林 《Journal of Beijing Institute of Technology》 EI CAS 2006年第1期22-26,共5页
The enhancement of vehicle handling stability and maneuverability through active and independent rear wheels control is presented. Firstly, the configuration of four-wheel independent steering prototype vehide is intr... The enhancement of vehicle handling stability and maneuverability through active and independent rear wheels control is presented. Firstly, the configuration of four-wheel independent steering prototype vehide is introduced briefly. Then the concrete overall design of the electronic controllers of four wheel independent steering system (4WIS) is formulated in details. Under the control strategy of zero sideslip angle at mass center, the mathematical model of 4WIS is established to deduce the equations of separated rear wheel steering angles. According to these equations, simulation analysis for 4WIS vehicle performances is finished to show that 4WIS vehicle can improve the maneuverability greatly at low speed and increase the handling stability at high speed. Finally, the road test of 4WIS vehide has performed to verify the correctness of simulation and show that compared with the conventional four wheel steering (4WS) vehicle, the 4WIS vehicle not only improves the kinematical harmony but also decreases steering resistance and lighten abrasion of tires. 展开更多
关键词 four-wheel independent steering system (4WIS) control strategy four-wheel steering system (4WS)
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Attributes reduct and decision rules optimization based on maximal tolerance classification in incomplete information systems with fuzzy decisions 被引量:1
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作者 Fang Yang Yanyong Guan +1 位作者 Shujin Li Lei Du 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2010年第6期995-999,共5页
A new approach to knowledge acquisition in incomplete information system with fuzzy decisions is proposed. In such incomplete information system, the universe of discourse is classified by the maximal tolerance classe... A new approach to knowledge acquisition in incomplete information system with fuzzy decisions is proposed. In such incomplete information system, the universe of discourse is classified by the maximal tolerance classes, and fuzzy approximations are defined based on them. Three types of relative reducts of maximal tolerance classes are then proposed, and three types of fuzzy decision rules based on the proposed attribute description are defined. The judgment theorems and approximation discernibility functions with respect to them are presented to compute the relative reduct by using Boolean reasoning techniques, from which we can derive optimal fuzzy decision rules from the systems. At last, three types of relative reducts of the system and their computing methods are given. 展开更多
关键词 rough sets information systems maximal tolerance class attribute reduct decision rules.
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ON THE MAXIMAL DISJOINT SYSTEM IN Riesz ALGEBRAS AND REPRESENTATION
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作者 徐景峰 熊洪允 《Transactions of Tianjin University》 EI CAS 1999年第1期85-87,共3页
Let E be an Archimedean Riesz algebra possessing a weak unit element e and a maximal disjoint system {e,: i∈I} in which e, is a projection element for each i. The principal band generated by eiis denoted by B(ei). T... Let E be an Archimedean Riesz algebra possessing a weak unit element e and a maximal disjoint system {e,: i∈I} in which e, is a projection element for each i. The principal band generated by eiis denoted by B(ei). The main result in this paper says that if there exists a completely regular Hausdorff space X such that E is Riesz algebra isomorphic to C(X) then for every i ∈ I there exists a completely regular Hausdorff space X, such that B(ei) is Riesz algebra isomorphic to C(Xi). Under an additional condition the inverse holds. 展开更多
关键词 Riesz algebra maximal disjoint system REPRESENTATION projection element weak unit element
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Independent Component Analysis Based Blind Adaptive Interference Reduction and Symbol Recovery for OFDM Systems 被引量:4
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作者 LUO Zhongqiang ZHU Lidong LI Chengjie 《China Communications》 SCIE CSCD 2016年第2期41-54,共14页
To overcome the inter-carrier interference (ICI) of orthogonal frequency division multiplexing (OFDM) systems subject to unknown carrier frequency offset (CFO) and multipath, this paper develops a blind adaptive... To overcome the inter-carrier interference (ICI) of orthogonal frequency division multiplexing (OFDM) systems subject to unknown carrier frequency offset (CFO) and multipath, this paper develops a blind adaptive interference suppression scheme based on independent component analysis (ICA). Taking into account statistical independence of subcarriers' signals of OFDM, the signal recovery mechanism is investigated to achieve the goal of blind equalization. The received OFDM signals can be considered as the mixed observation signals. The effect of CFO and multipath corresponds to the mixing matrix in the problem of blind source separation (BSS) framework. In this paper, the ICA- based OFDM system model is built, and the proposed ICA-based detector is exploited to extract source signals from the observation of a received mixture based on the assumption of statistical independence between the sources. The blind separation technique can increase spectral efficiency and provide robustness performance against erroneous parameter estimation problem. Theoretical analysis and simulation results show that compared with the conventional pilot-based scheme, the improved performance of OFDM systems is obtained by the proposed ICA-based detection technique. 展开更多
关键词 orthogonal frequency divisionmultiplexing (OFDM) blind source separation(BSS) independent component analysis (ICA) blind interference suppression symbol recovery
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Stability and stabilization of discrete T-S fuzzy time-delay system based on maximal overlapped-rules group 被引量:1
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作者 Songtao Zhang Xiaowei Zhao Jiantong Zhang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2016年第1期201-210,共10页
The problems of stability and stabilization for the discrete Takagi-Sugeno(T-S) fuzzy time-delay system are investigated.By constructing a discrete piecewise Lyapunov-Krasovskii function(PLKF) in each maximal over... The problems of stability and stabilization for the discrete Takagi-Sugeno(T-S) fuzzy time-delay system are investigated.By constructing a discrete piecewise Lyapunov-Krasovskii function(PLKF) in each maximal overlapped-rules group(MORG),a new sufficient stability condition for the open-loop discrete T-S fuzzy time-delay system is proposed and proved.Then the systematic design of the fuzzy controller is investigated via the parallel distributed compensation control scheme,and a new stabilization condition for the closed-loop discrete T-S fuzzy time-delay system is proposed.The above two sufficient conditions only require finding common matrices in each MORG.Compared with the common Lyapunov-Krasovskii function(CLKF) approach and the fuzzy Lyapunov-Krasovskii function(FLKF) approach,these proposed sufficient conditions can not only overcome the defect of finding common matrices in the whole feasible region but also largely reduce the number of linear matrix inequalities to be solved.Finally,simulation examples show that the proposed PLKF approach is effective. 展开更多
关键词 stability analysis maximal overlapped-rules group(MORG) Takagi-Sugeno(T-S)fuzzy model discrete time-delay system piecewise Lyapunov-Krasovskii function(PLKF).
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The Number of Maximal Independent Sets in Quasi-Tree Graphs and Quasi-Forest Graphs
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作者 Jenq-Jong Lin Min-Jen Jou 《Open Journal of Discrete Mathematics》 2017年第3期134-147,共14页
A maximal independent set is an independent set that is not a proper subset of any other independent set. A connected graph (respectively, graph) G with vertex set V(G) is called a quasi-tree graph (respectively, quas... A maximal independent set is an independent set that is not a proper subset of any other independent set. A connected graph (respectively, graph) G with vertex set V(G) is called a quasi-tree graph (respectively, quasi-forest graph), if there exists a vertex x &isin;V(G) such that G &minus;x?is a tree (respectively, forest). In this paper, we survey on the large numbers of maximal independent sets among all trees, forests, quasi-trees and quasi-forests. In addition, we further look into the problem of determining the third largest number of maximal independent sets among all quasi-trees and quasi-forests. Extremal graphs achieving these values are also given. 展开更多
关键词 maximal independent Set Quasi-Tree GRAPH Quasi-Forest GRAPH EXTREMAL GRAPH
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An Alternative Proof of the Largest Number of Maximal Independent Sets in Connected Graphs Having at Most Two Cycles
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作者 Min-Jen Jou Jenq-Jong Lin 《Open Journal of Discrete Mathematics》 2016年第4期227-237,共11页
G. C. Ying, Y. Y. Meng, B. E. Sagan, and V. R. Vatter [1] found the maximum number of maximal independent sets in connected graphs which contain at most two cycles. In this paper, we give an alternative proof to deter... G. C. Ying, Y. Y. Meng, B. E. Sagan, and V. R. Vatter [1] found the maximum number of maximal independent sets in connected graphs which contain at most two cycles. In this paper, we give an alternative proof to determine the largest number of maximal independent sets among all connected graphs of order n ≥ 12, which contain at most two cycles. We also characterize the extremal graph achieving this maximum value. 展开更多
关键词 maximal independent Set Connected Graph Having at Most Two Cycles
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CONTROLLABILITY OF DELAY DEGENERATE CONTROL SYSTEMS WITH INDEPENDENT SUBSYSTEMS
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作者 蒋威 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2003年第6期706-713,共8页
The controllability of delay degenerate differential control systems is discussed. Firstly, delay degenerate differential control system was transformed to be canonical form, and the connected terms were gotten rid of... The controllability of delay degenerate differential control systems is discussed. Firstly, delay degenerate differential control system was transformed to be canonical form, and the connected terms were gotten rid of, had delay degenerate differential control systems with independent subsystems. For the general delay degenerate differnetial control systems, it was gotten that the necessary and sufficient condition of that they are controllable is that their reachable set is equal to the whole space. For the delay degenerate differential control systems with independent subsystems, it was gotten that the necessary and sufficient conditions of that they are controllable are that their reachable sets are equal to their corresponding subspaces. Then some algebra criteria were gotten. Finally, an example was given to illustrate the main results. 展开更多
关键词 independent subsystem delay degenerate differential control system CONTROLLABILITY
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Independent Cycle Time Assignment for Min-max Systems
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作者 Wen-De Chen Yue-Gang Tao Hong-Nian Yu 《International Journal of Automation and computing》 EI 2010年第2期254-260,共7页
A variety of problems in digital circuits, computer networks, automated manufacturing plants, etc., can be modeled as min-max systems. The cycle time is an important performance metric of such systems. In this paper, ... A variety of problems in digital circuits, computer networks, automated manufacturing plants, etc., can be modeled as min-max systems. The cycle time is an important performance metric of such systems. In this paper, we focus on the cycle time assignment of minimax systems which corresponds to the pole assignment problem in traditional linear control systems. For the min- max system with max-plus inputs and outputs, we show that the cycle time can be assigned disjointedly by a state feedback, if and only if the system is reachable. Furthermore, a necessary and sufficient condition for the cycle time to be assigned independently by a state feedback is given. The methods are constructive, and some numerical examples are given to illustrate how the methods work in practice. 展开更多
关键词 Cycle time coloring graph independent assignment min-max systems state feedback.
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The maximal Lyapunov exponent of a co-dimension two-bifurcation system excited by a bounded noise
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作者 Sheng-Hong Li Xian-Bin Liu 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2012年第2期511-519,共9页
In the present paper, the maximal Lyapunov ex- ponent is investigated for a co-dimension two bifurcation system that is on a three-dimensional central manifold and subjected to parametric excitation by a bounded noise... In the present paper, the maximal Lyapunov ex- ponent is investigated for a co-dimension two bifurcation system that is on a three-dimensional central manifold and subjected to parametric excitation by a bounded noise. By using a perturbation method, the expressions of the invari- ant measure of a one-dimensional phase diffusion process are obtained for three cases, in which different forms of the matrix B, that is included in the noise excitation term, are assumed and then, as a result, all the three kinds of singular boundaries for one-dimensional phase diffusion process are analyzed. Via Monte-Carlo simulation, we find that the an- alytical expressions of the invariant measures meet well the numerical ones. And furthermore, the P-bifurcation behav- iors are investigated for the one-dimensional phase diffusion process. Finally, for the three cases of singular botmdaries for one-dimensional phase diffusion process, analytical ex- pressions of the maximal Lyapunov exponent are presented for the stochastic bifurcation system. 展开更多
关键词 maximal Lyapunov exponent Perturbationmethod. Bounded noise. Diffusion process
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The Length of the Element of Maximal Length in the Coxeter System of Type A_n,B_n/C_n and D_n
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作者 付治国 南基洙 《Northeastern Mathematical Journal》 CSCD 2006年第4期395-403,共9页
Let w be the element of maximal length in a finite irreducible Coxeter system (W, S). In the present paper, we get the length of w when (W, S) is of type An, Bn/Cn or Dn.
关键词 Coxeter system Coxeter group maximal length
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Optimal gear shift control strategy for positive independent mechanical split path transmission with automatic shift system
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作者 陈泳丹 席军强 陈慧岩 《Journal of Beijing Institute of Technology》 EI CAS 2011年第3期387-393,共7页
An improvement strategy which controls the shift effort and the power summing planetary gear set of steering clutches and brakes have been proposed based on the dynamic model of synchroniser in order to decrease the w... An improvement strategy which controls the shift effort and the power summing planetary gear set of steering clutches and brakes have been proposed based on the dynamic model of synchroniser in order to decrease the wear of synchroniser inserts, make gear shift easy and reduce the shock noise for a positive independent mechanical split path transmission which attached an auto- matic shift system when shifting. A kinetics model for the process of synchroniser engagement is built and analyzed in the paper. Thus for optimizing the gear shift process which is divided into three phases a model reference fuzzy self-adaption system is adopted. Through a 6 000 km road experiment, the control strategy has proved feasible and dependable. 展开更多
关键词 positive independent mechanical split path transmission synchroniser engagement steering clutch brake shift effort
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Delay-independent robust guaranteed-cost control for uncertain linear neutral systems 被引量:4
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作者 Li Hongfei Zhou Jun 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2007年第4期858-864,共7页
This article concerns the delay-independent guaranteed-cost control problem via memoryless state feedback for a class of neutral-type systems with structural uncertainty and a given quadratic cost function. New delay-... This article concerns the delay-independent guaranteed-cost control problem via memoryless state feedback for a class of neutral-type systems with structural uncertainty and a given quadratic cost function. New delay-independent conditions for the existence of the guaranteed-cost controller are presented in the term of LMIs. An algorithm involving optimization is proposed to design a controller achieving an optimal guaranteed-cost, such that, the system can be stabilized for all admissible uncertainties. A numerical example is provided to illustrate the feasibility of the proposed method. 展开更多
关键词 neutral system guaranteed cost control LMI method DELAY-independent
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Simulation Analysis of Characteristics for Independent Metering Control System Based on Downstream Compensation
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作者 Guotai Zhang Jie Xu +1 位作者 Jing Yang Kailei Liu 《World Journal of Engineering and Technology》 2019年第3期536-547,共12页
Aiming at the shortcomings of the separate meter in and separate meter out?hydraulic system, a new type of independent metering control system is proposed by referring to the principle of load-sensing system. The valv... Aiming at the shortcomings of the separate meter in and separate meter out?hydraulic system, a new type of independent metering control system is proposed by referring to the principle of load-sensing system. The valve group unit in the system is designed, and the AMESim/Matlab cosimulation model of the component and system is established. The actuator speed control, energy consumption and anti-flow saturation characteristics of the system are discussed. The simulation result shows that the system proposed in this article can achieve?better performances. 展开更多
关键词 independent METERING Control Pressure COMPENSATION COSIMULATION
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