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DISPLACEMENT CONTROL AND KINETIC ANALYSIS OF A NOVEL VARIABLE DISPLACEMENT COMPRESSOR FOR AUTOMOTIVE AIR CONDITIONER 被引量:7
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作者 Yuan Xiaomei,Chen Zhijiu (Institute of Refrigeration and Cryogenics Engineering, Shanghai Jiaotong University) 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2001年第4期325-329,共5页
A novel variable displacement compressor (VDC) for automotive air conditioner (AAC) is introduced, which inherits the advantages of common wobble plate type VDC. It has fewer parts and makes less noise, and instead of... A novel variable displacement compressor (VDC) for automotive air conditioner (AAC) is introduced, which inherits the advantages of common wobble plate type VDC. It has fewer parts and makes less noise, and instead of pneumatic valve the displacement is controlled by electronic control valve. In order to know the control mechanism well and get a good control effect, a mathematical model for the variable displacement mechanism is developed according to the geometrical and kinematical information of the compressor. Using the model, the effect of relevant parameters on variable displace control is estimated. It is helpful to make the optimum decision in the flow control of AAC. As the novel displacement control device, the structure and control rule of electronic control valve is introduced. It can get better effect than the conventional pneumatic valves. And by using this new electronic control device, the optimum systemic control of AAC is available. 展开更多
关键词 Displacement control Kinetic analysis Automotive air conditioner (AAC) Variable displacement compressor(VDC)
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Analysis of the Ore-Controlling Structure of Ductile Shear Zone Type Gold Deposit in Southern Beishan Area, Gansu, Northwest China 被引量:3
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作者 陈柏林 吴淦国 +3 位作者 叶德金 刘晓春 舒斌 杨农 《Journal of China University of Geosciences》 SCIE CSCD 2007年第1期30-38,共9页
The ductile shear zone-type gold deposit is a kind that both the ore-forming mechanism and ore-controlling factors are closely related to the ductile shear zone and its evolution. Ductile shear zone develops in Beisha... The ductile shear zone-type gold deposit is a kind that both the ore-forming mechanism and ore-controlling factors are closely related to the ductile shear zone and its evolution. Ductile shear zone develops in Beishan area, Gansu of Northwest China, and develops especially well in the south belt. The controls of the ductile shear zone on gold deposits are as follows. (1) The regional distribution of gold deposits (and gold spots) is controlled by the ductile shear zone. (2) The ductile-brittle shear zone is formed in the evolution process of ductile shear zone and both are only ore-bearing structures and control the shape, attitude, scale, and distribution of mineralization zones and ore-bodies. (3) Compresso-shear ductile deformation results in that the main kind of gold mineralization is altered mylonite type and the main alteralization is metasomatic. (4) Ore-bearing fracture systems are mainly P-type ones, some D-type and R-type ones, but only individual R'-type and T-type ones. (5) Dynamic differen- tiation and dynamic metamorphic hydrothermal solution resulting from ductile deformation is one of the sources of ore-forming fluid of gold mineralization, and this is identical with that ore-forming materials are mainly from metamorphic rocks, and ore-forming fluid is mainly composed of metamorphic water, and with the fluid inclusion and geo-chemical characteristics of the deposit. (6) There is a negative correlation between the gold abundance and susceptibility anlsotropy (P) of the altered mylonlte samples from the deposit, which shows that the gold mineralization is slightly later than the structural deformation. All above further expound the ore-forming model of the ductile shear zone type of gold deposits. 展开更多
关键词 analysis of ore.controlling structure gold deposit ductile shear zone Beishanarea of Gansu Northwest China
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QUALITY CONTROL OF SEMICONDUCTOR PACKAGING BASED ON PRINCIPAL COMPONENTS ANALYSIS 被引量:2
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作者 HE Shuguang QI Ershi HE Zhen NIE Bin 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2007年第6期84-86,共3页
5 critical quality characteristics must be controlled in the surface mount and wire-bond process in semiconductor packaging. And these characteristics are correlated with each other. So the principal components analy... 5 critical quality characteristics must be controlled in the surface mount and wire-bond process in semiconductor packaging. And these characteristics are correlated with each other. So the principal components analysis(PCA) is used in the analysis of the sample data firstly. And then the process is controlled with hotelling T^2 control chart for the first several principal components which contain sufficient information. Furthermore, a software tool is developed for this kind of problems. And with sample data from a surface mounting device(SMD) process, it is demonstrated that the T^2 control chart with PCA gets the same conclusion as without PCA, but the problem is transformed from high-dimensional one to a lower dimensional one, i.e., from 5 to 2 in this demonstration. 展开更多
关键词 Semiconductor packaging Principal components analysis Quality control
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Effects of Joint Controller on Analytical Modal Analysis of Rotational Flexible Manipulator 被引量:7
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作者 CHU Ming ZHANG Yanheng +1 位作者 CHEN Gang SUN Hanxu 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2015年第3期460-469,共10页
Modal analysis is a fundamental and important task for modeling and control of the flexible manipulator. However, almost all of the traditional modal analysis methods view the flexible manipulator as a pure mechanical... Modal analysis is a fundamental and important task for modeling and control of the flexible manipulator. However, almost all of the traditional modal analysis methods view the flexible manipulator as a pure mechanical structure and neglect feedback action of joint controller. In order to study the effects of joint controller on the modal analysis of rotational flexible manipulator, a closed-loop analytical modal analysis method is proposed. Firstly, two exact boundary constraints, namely servo feedback constraint and bending moment constraint, are derived to solve the vibration partial differential equation. It is found that the stiffness and damping gains of joint controller are both included in the boundary conditions, which lead to an unconventional secular term. Secondly, analytical algorithm based on Ritz approach is developed by using Laplace transform and complex modal approach to obtain the natural frequencies and mode shapes. And then, the numerical simulations are performed and the computational results show that joint controller has pronounced influence on the modal parameters: joint controller stiffness reduces the natural frequency, while joint controller damping makes the shape phase non-zero. Furthermore, the validity of the presented conclusion is confirmed through experimental studies. These findings are expected to improve the performance of dynamics simulation systems and model-based controllers. 展开更多
关键词 flexible manipulator analytical modal analysis boundary constraints joint controller
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Analysis of one dimensional and two dimensional fuzzy controllers
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作者 Ban Xiaojun Gao Xiaozhi +1 位作者 Huang Xianlin Wu Tianbao 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2006年第2期362-373,共12页
The analytical structures and the corresponding mathematical properties of the one dimensional and two dimensional fuzzy controllers are first investigated in detail. The nature of these two kinds of fuzzy controllers... The analytical structures and the corresponding mathematical properties of the one dimensional and two dimensional fuzzy controllers are first investigated in detail. The nature of these two kinds of fuzzy controllers is next probed from the perspective of control engineering. For the one dimensional fuzzy controller, it is concluded that this controller is a combination of a saturation element and a nonlinear proportional controller, and the system that employs the one dimensional fuzzy controller is the combination of an open-loop control system and a closedloop control system. For the latter case, it is concluded that it is a hybrid controller, which comprises the saturation part, zero-output part, nonlinear derivative part, nonlinear proportional part, as well as nonlinear proportional-derivative part, and the two dimensional fuzzy controller-based control system is a loop-varying system with varying number of control loops. 展开更多
关键词 one dimensional fuzzy controller two dimensional fuzzy controller analytical structures fuzzy inference control system analysis.
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Stability analysis of the simplest Takagi-Sugeno fuzzy control system using circle criterion
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作者 Lu Hongqian Huang Xianlin +2 位作者 Gao X. Z. Ban Xiaojun Yin Hang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2007年第2期311-319,共9页
A frequency-domain-based sufficient condition is derived to guarantee the globally asymptotic stability of the simplest Takagi-Sugeno (T-S) fuzzy control system by using the circle criterion. The analysis is perform... A frequency-domain-based sufficient condition is derived to guarantee the globally asymptotic stability of the simplest Takagi-Sugeno (T-S) fuzzy control system by using the circle criterion. The analysis is performed in the frequency domain, and hence the condition is of great significance when the frequency-response method, which is widely used in the linear control theory and practice, is employed to synthesize the simplest T-S fuzzy controller. Besides, this sufficient condition is featured by a graphical interpretation, which makes the condition straightforward to be used. Comparisons are drawn between the performance of the simplest T-S fuzzy controller and that of the linear compensator. Two numerical examples are presented to demonstrate how this sufficient condition can be applied to both stable and unstable plants. 展开更多
关键词 T-S fuzzy controller Stability analysis Circle criterion Frequency response method.
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Analysis of Beta-blockers in Doping Control
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作者 Hong Jin DUAN Hong Ju FANG Yan Qing XU Tong Hui ZHOU Hua CHI Yun WU You Xuan XU Institute of Materia Medica,Chinese Academy of Medical Sciences,Beijing 100050,China 《Chinese Chemical Letters》 SCIE CAS CSCD 1990年第3期231-234,共4页
A retiabte and sensitive method is developed for the detection of β-blockers which are excreted in free or conjugated forms in human urine.9 β-blockers were derivatized by MSTFA and MBTFA and subjected to GC/MSB ana... A retiabte and sensitive method is developed for the detection of β-blockers which are excreted in free or conjugated forms in human urine.9 β-blockers were derivatized by MSTFA and MBTFA and subjected to GC/MSB analysis.Both chromato- grams and mass spectrometric data were obtained from full scanning mode.This method is suitable for routine screening and confirmation of β-blockers in doping control. 展开更多
关键词 analysis of Beta-blockers in Doping control
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Research on Self-balancing Two Wheels Mobile Robot Control System Analysis
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作者 Hla Myo Tun Myat Su Nwe +3 位作者 Zaw Min Naing Maung Maung Latt Devasis Pradhan Prasanna Kumar Sahu 《Electrical Science & Engineering》 2022年第1期7-20,共14页
The paper presents the research on self-balancing two-wheels mobile robot control system analysis with experimental studies.The research problem in this work is to stabilize the mobile robot with self-control and to c... The paper presents the research on self-balancing two-wheels mobile robot control system analysis with experimental studies.The research problem in this work is to stabilize the mobile robot with self-control and to carry the sensitive things without failing in a long span period.The main objective of this study is to focus on the mathematical modelling of mobile robot from laboratory scale to real world applications.The numerical expression with mathematical modelling is very important to control the mobile robot system with linearization.The fundamental concepts of dynamic system stability were utilized for maintaining the stability of the constructed mobile robot system.The controller design is also important for checking the stability and the appropriate controller design is proportional,integral,and derivative-PID controller and Linear Quadratic Regulator(LQR).The steady state error could be reduced by using such kind of PID controller.The simulation of numerical expression on mathematical modeling was conducted in MATLAB environments.The confirmation results from the simulation techniques were applied to construct the hardware design of mobile robot system for practical study.The results from simulation approaches and experimental approaches are matched in various kinds of analyses.The constructed mobile robot system was designed and analyzed in the control system design laboratory of Yangon Technological University(YTU). 展开更多
关键词 Mobile robot Self-balancing robot control system design PID controller Dynamic control system analysis
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Observer-based backstepping longitudinal control for carrier-based UAV with actuator faults 被引量:9
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作者 Fengying Zheng Ziyang Zhen Huajun Gong 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2017年第2期322-337,共16页
The paper presents the longitudinal control for the carrier-based unmanned aerial vehicle (UAV) system with unmeasured states, actuator faults, control input constraints, and external disturbances. By combining output... The paper presents the longitudinal control for the carrier-based unmanned aerial vehicle (UAV) system with unmeasured states, actuator faults, control input constraints, and external disturbances. By combining output state observer, adaptive fuzzy control, and constraint backstepping technology, a robust fault tolerant control approach is proposed. An output state observer with fuzzy logic systems is developed to estimate unmeasured states, and command filters rather than differentiations of virtual control law are used to solve the computational complexity problem in traditional backstepping. Additionally, a robust term is introduced to offset the fuzzy adaptive estimation error and external disturbance, and an appropriate fault controller structure with matching conditions obtained from fault compensation is proposed. Based on the Lyapunov theory, the designed control program is illustrated to guarantee that all the closed-loop signals of the given system are bounded, and the output errors converge to a small neighborhood of zero. A carrier-based UAV nonlinear longitudinal model is employed to testify the feasibility and validity of the control scheme. The simulation results show that all the controllers can perform at a satisfactory level of reference tracking despite the existence of unknown aerodynamic parameters and actuator faults. ? 2017 Beijing Institute of Aerospace Information. 展开更多
关键词 Actuators Aircraft control BACKSTEPPING control system analysis control theory controllers Error compensation Fault tolerance Flight control systems Fuzzy control Fuzzy filters Fuzzy logic State estimation Three term control systems Unmanned aerial vehicles (UAV)
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Neuro-Optimal Guidance Control for Lunar Soft Landing 被引量:3
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作者 Wang, Dayi Li, Tieshou +1 位作者 Yan, Hui Ma, Xingrui 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 1999年第3期22-31,共10页
Returning to moon has become a top topic recently. Many studies have shown that soft landing is a challenging problem in lunar exploration. The lunar soft landing in this paper begins from a 100 km circular lunar park... Returning to moon has become a top topic recently. Many studies have shown that soft landing is a challenging problem in lunar exploration. The lunar soft landing in this paper begins from a 100 km circular lunar parking orbit. Once the landing area has been selected and it is time to deorbit for landing, a ΔV burn of 19.4 m/s is performed to establish a 100×15 km elliptical orbit. At perilune, the landing jets are ignited, and a propulsive landing is performed. A guidance and control scheme for lunar soft landing is proposed in the paper, which combines optimal theory with nonlinear neuro-control. Basically, an optimal nonlinear control law based on artificial neural network is presented, on the basis of the optimum trajectory from perilune to lunar surface in terms of Pontryagin's maximum principle according to the terminal boundary conditions and performance index. Therefore some optimal control laws can be carried out in the soft landing system due to the nonlinear mapping function of the neural network. The feasibility and validity of the control laws are verified in a simulation experiment. 展开更多
关键词 Boundary conditions Computer simulation control system analysis control system synthesis Functions Lunar landing Lunar missions Maximum principle Neural networks Nonlinear control systems Optimal control systems ORBITS
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Static Analysis of Java Bytecode 被引量:1
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作者 Jian\|jun Zhao Department of Computer Science and Engineering, Fukuoka Institute of Technology, Fukuoka 811 0295,Japan 《Wuhan University Journal of Natural Sciences》 CAS 2001年第Z1期383-390,共8页
Understanding control flows in a computer program is essential for many software engineering tasks such as testing, debugging, reverse engineering, and maintenance. In this paper ,we present a control flow analysis te... Understanding control flows in a computer program is essential for many software engineering tasks such as testing, debugging, reverse engineering, and maintenance. In this paper ,we present a control flow analysis technique to analyze the control flow in Java bytecode. To perform the analysis, we construct a control flow graph(CFG) for Java bytecode not only at the intraprocedural level but also at the interprocedural level. We also discuss some applications of a CFG in a maintenance environment for Java bytecode. 展开更多
关键词 control flow analysis Java virtual machine software testing software maintenance.
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Computational mission analysis and conceptual system design for super low altitude satellite 被引量:1
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作者 Ming Xu Jinlong Wang Nan Zhou 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2014年第1期43-58,共16页
This paper deals with system engineering and design methodology for super low altitude satel ites in the view of the com-putational mission analysis. Due to the slight advance of imaging instruments, such as the focus... This paper deals with system engineering and design methodology for super low altitude satel ites in the view of the com-putational mission analysis. Due to the slight advance of imaging instruments, such as the focus of camera and the image element of charge coupled device (CCD), it is an innovative and economical way to improve the camera’s resolution to enforce the satel ite to fly on the lower altitude orbit. DFH-3, the mature satel ite bus de-veloped by Chinese Academy of Space Technology, is employed to define the mass and power budgets for the computational mis-sion analysis and the detailed engineering design for super low altitude satel ites. An effective iterative algorithm is proposed to solve the ergodic representation of feasible mass and power bud-gets at the flight altitude under constraints. Besides, boundaries of mass or power exist for every altitude, where the upper boundary is derived from the maximum power, while the minimum thrust force holds the lower boundary before the power reaching the initial value. What’s more, an analytical algorithm is employed to numerical y investigate the coverage percentage over the altitude, so that the nominal altitude could be selected from al the feasi-ble altitudes based on both the mass and power budgets and the repetitive ground traces. The local time at the descending node is chosen for the nominal sun-synchronous orbit based on the average evaluation function. After determining the key orbital ele-ments based on the computational mission analysis, the detailed engineering design on the configuration and other subsystems, like power, telemetry telecontrol and communication (TT&amp;C), and attitude determination and control system (ADCS), is performed based on the benchmark bus, besides, some improvements to the bus are also implemented to accommodate the flight at a super low altitude. Two operation strategies, drag-free closed-loop mode and on/off open-loop mode, are presented to maintain the satel-lite’s altitude. Final y, a flight planning schedule for the satel ite is demonstrated from its launch into the initial altitude at the very beginning to its decay to death in the end. 展开更多
关键词 super low altitude computational mission analysis drag free control mass and power budget.
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Influence of Wall Effect on Comprehensive Controllability for Ducted Fan Aircraft
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作者 Tianfu Ai Changle Xiang +2 位作者 Bin Xu Wei Fan Yibo Zhang 《Journal of Beijing Institute of Technology》 EI CAS 2020年第4期581-591,共11页
A novel coaxial ducted fan structure aircraft is proposed to enable the aircraft near vertical walls at high altitudes.The state space equation of the system can be obtained by correlation deduction and identification... A novel coaxial ducted fan structure aircraft is proposed to enable the aircraft near vertical walls at high altitudes.The state space equation of the system can be obtained by correlation deduction and identification of the whole prototype model.Based on the duct test bench experiment and computational fluid dynamics(CFD)simulation analysis,the expressions between the different distances dWE from the rotor center of the prototype to the wall and the thrust,reaction torque,and tilting moment of the system under hovering conditions are obtained.The influence of the wall effect of the prototype is incorporated into the system model to analyze the relationship between distance dWE and the comprehensive controllability of the system.The results show that the system comprehensive controllability vector of other channels changes little with the decrease of the distance dWE,and only the controllability vector of the rolling channel increases significantly.At the same time,the tilting moment also increases significantly,which strengthens the tendency of the prototype to tilt towards the wall. 展开更多
关键词 coaxial ducted fan aircraft hovering condition wall effect tilting moment comprehensive controllability analysis
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Design of an Interpolated Controller for Stabilization of a Plant with Variable Operating Condition
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作者 Yuan, Xiangyang Shi, Songjiao Ikeda, Masao 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2000年第2期39-47,共9页
In this paper, the stabilization of a linear SISO plant with variable operating condition is considered. The plant is described by a linear interpolation of proper stable co-prime factorizations of the transfer functi... In this paper, the stabilization of a linear SISO plant with variable operating condition is considered. The plant is described by a linear interpolation of proper stable co-prime factorizations of the transfer functions at two representative operating points. An interpolation of the stabilizing controllers for the representative models is designed to stabilize the plant, and the necessary and sufficient condition for the plant to be stabilized by the proposed controller is presented using the Nevanlinna-Pick interpolation theory. It is shown that the class of stabilization plants via the proposed controller in the paper is larger than that by the controller in reference. An example is also given to illustrate this fact. 展开更多
关键词 Closed loop control systems control system analysis INTERPOLATION System stability Transfer functions
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Dynamic Logic in Control
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作者 He, Weidong Yu, Xinyao +1 位作者 Chen, Zhongji Zhang, Minglian 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 1994年第3期20-31,共12页
For the dynamic property in the control system, in this paper we advance dynamic logic to analyze and synthesize the control problems. This approach is similar to the way in which people always resolve such problems, ... For the dynamic property in the control system, in this paper we advance dynamic logic to analyze and synthesize the control problems. This approach is similar to the way in which people always resolve such problems, and it can reflect the nature of the system. The dynamic logic combines the people's logic analysis with the dynamic property of the control system. On the basis of the dynamic logic qualitative model, the analyzing process and synthesizing process may go on. So there are many of the non-linear and logic factors which can be directly taken into consideration in the analyzing and designing process. The combination of the human intelligence and artificial intelligent techniques with the conventional methods of analysis and design, has provide an effective tool for the qualitative analysis and the qualitative design of the intelligent control system. We have successfully resolved the stabilizing problem of the inverted pendulum with dynamic logic. 展开更多
关键词 Artificial intelligence control system analysis control system synthesis Intelligent control Mathematical models System stability
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Discrete Quasi-Sliding Mode Tracking Controller with Time Delay Technique
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作者 Yu, Shuanghe Fu, Peichen Qiang, Wenyi 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 1999年第3期44-49,共6页
Robust discrete quasi-sliding mode tracking controller is developed with discrete reaching law for trajectory tracking in the presence of modeling uncertainty and unknown disturbance. The conventional prior knowledge ... Robust discrete quasi-sliding mode tracking controller is developed with discrete reaching law for trajectory tracking in the presence of modeling uncertainty and unknown disturbance. The conventional prior knowledge of uncertainty upper bounds being replaced by an on-line estimation used in the controller to cancel the slowly varying uncertainties by the mechanism of time delay. This method reduces the feedback gain substantially and improves tracking accuracy. The system behavior in the vicinity of the sliding surface is examined for the existence and bandwidth of quasi-sliding mode. Simulation results show the effectiveness of the strategy. 展开更多
关键词 BANDWIDTH Computer simulation control system analysis control system synthesis Delay control systems Feedback control Online systems Parameter estimation Uncertain systems
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On the Solutions of the Matrix Equations in Optimal Stochastic Control
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作者 Deng, Feiqi Hu, Gang +1 位作者 Liu, Yongqing Feng, Zhaoshu 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 1999年第3期38-43,共6页
In this paper, the matrix algebraic equations involved in the optimal control problem of time-invariant linear Ito stochastic systems, named Riccati- Ito equations in the paper, are investigated. The necessary and suf... In this paper, the matrix algebraic equations involved in the optimal control problem of time-invariant linear Ito stochastic systems, named Riccati- Ito equations in the paper, are investigated. The necessary and sufficient condition for the existence of positive definite solutions of the Riccati- Ito equations is obtained and an iterative solution to the Riccati- Ito equations is also given in the paper thus a complete solution to the basic problem of optimal control of time-invariant linear Ito stochastic systems is then obtained. An example is given at the end of the paper to illustrate the application of the result of the paper. 展开更多
关键词 Computational methods control system analysis control system synthesis Iterative methods Linear control systems Matrix algebra Optimal control systems Riccati equations
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VIBRATION CONTROL AND EXPERIMENT OF THREE-RING REDUCER 被引量:2
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作者 Zhu, Caichao Qin, Datong Li, Runfang 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 1998年第4期72-78,共7页
The three ring reducer is studied both in theory and experiment. In order to improve the dynamic characteristics and reduce the vibration and noise, based on the sensitivity analysis of design parameters of dynamic c... The three ring reducer is studied both in theory and experiment. In order to improve the dynamic characteristics and reduce the vibration and noise, based on the sensitivity analysis of design parameters of dynamic characteristics, the system geometry parameters are optimized, and the structure of reducer is developed according to the optimum result, then the specimens of reducer are designed and manufactured. The effect of the structure development has been verified by comparing the original and developed reducer through the vibration tests. 展开更多
关键词 Three ring reducer Dynamic analysis Vibration control
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Multi-range controller design for highly nonlinear systems with application to unmanned aerial vehicles
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作者 Amir Nassirharand 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2010年第3期491-495,共5页
A new procedure for a design of multi-range controllers for use with highly nonlinear systems is developed.The procedure involves obtaining the describing function models of the nonlinear plant by software followed by... A new procedure for a design of multi-range controllers for use with highly nonlinear systems is developed.The procedure involves obtaining the describing function models of the nonlinear plant by software followed by designing a controller at nominal conditions.Then,the controller parameters are optimized to yield a satisfactory closed-loop response at all operating regimes.Finally,the performance and stability of the closed-loop system comprised of the designed controller and the nonlinear plant are verified.The procedure and the associated software are applied to a nonlinear control problem of the sort encountered in aerospace,and the results are compared with two other approaches. 展开更多
关键词 control theory optimization describing functions Fourier analysis stabilization.
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Response surface modeling-based source contribution analysis and VOC emission control policy assessment in a typical ozone-polluted urban Shunde,China 被引量:7
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作者 Zhiqiang You Yun Zhu +7 位作者 Carey Jang Shuxiao Wang Jian Gao Che-Jen Lin Minhui Li Zhenghua Zhu Hao Wei Wenwei Yang 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2017年第1期294-304,共11页
To develop a sound ozone(O_3) pollution control strategy,it is important to well understand and characterize the source contribution due to the complex chemical and physical formation processes of O_3.Using the "Sh... To develop a sound ozone(O_3) pollution control strategy,it is important to well understand and characterize the source contribution due to the complex chemical and physical formation processes of O_3.Using the "Shunde" city as a pilot summer case study,we apply an innovative response surface modeling(RSM) methodology based on the Community Multi-Scale Air Quality(CMAQ) modeling simulations to identify the O_3 regime and provide dynamic analysis of the precursor contributions to effectively assess the O_3 impacts of volatile organic compound(VOC) control strategy.Our results show that Shunde is a typical VOC-limited urban O_3 polluted city.The "Jiangmen" city,as the main upper wind area during July 2014,its VOCs and nitrogen oxides(NO_x) emissions make up the largest contribution(9.06%).On the contrary,the contribution from local(Shunde) emission is lowest(6.35%) among the seven neighbor regions.The local VOCs industrial source emission has the largest contribution comparing to other precursor emission sectors in Shunde.The results of dynamic source contribution analysis further show that the local NO_x control could slightly increase the ground O_3 under low(10.00%) and medium(40.00%)reduction ratios,while it could start to turn positive to decrease ground O_3 under the high NO_x abatement ratio(75.00%).The real-time assessment of O_3 impacts from VOCs control strategies in Pearl River Delta(PRD) shows that the joint regional VOCs emission control policy will effectively reduce the ground O_3 concentration in Shunde. 展开更多
关键词 O_3 Response surface model Source contribution analysis VOCs control policy
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