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A Study of Model for Distributed Measurement and Control System 被引量:2
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作者 张劲 钟毅芳 《微计算机信息》 2003年第9期17-20,共4页
This paper is concerned with a method for forming distributed measurement and control system.A three-layer structure model based on network,physical node layer and func-tion node layer is discussed.It is designed on o... This paper is concerned with a method for forming distributed measurement and control system.A three-layer structure model based on network,physical node layer and func-tion node layer is discussed.It is designed on object-oriented software method.The model has a fine application prospect. 展开更多
关键词 分布式测控系统 面向对象 框架模型 软件方法 网络协议
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Design of a Modularized Automatic Measurement and Control System for LaserInduced Breakdown Spectrometer
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作者 丁宇 田地 +2 位作者 陈飞鹏 乔淑君 杨光 《Journal of Donghua University(English Edition)》 EI CAS 2014年第4期406-410,共5页
In order to improve the compatibility of laser-induced breakdown spectroscopy( LIBS) instrument for different types of parts and optimize the analysis and testing processes,a modularized automatic measurement and cont... In order to improve the compatibility of laser-induced breakdown spectroscopy( LIBS) instrument for different types of parts and optimize the analysis and testing processes,a modularized automatic measurement and control system was developed. Based on the characteristics of each LIBS component, the following development steps have been performed:( 1) a summary of characteristic parameters of the component are established;( 2) the integration mechanism of multiple electrical interfaces is designed;( 3) the component control instruction library is developed. The experimental results indicate that the measurement and control system is compatible with most LIBS parts in the market.Spectrometer and laser can be compatible with at least three different types of parts. In addition,a multilayer iterative testing process is designed to improve the efficiency of optimization process of LIBS parameters. The experimental results have shown that the automatic optimization of the delay time compared to the manual testing provides significant gain in testing efficiency. The range of delay time in the experiments is 1. 28 to 10. 28 μs and the step value is 1,0. 5,0. 2 and 0. 1 μs. The gain in testing efficiency has been found to be increased by 73. 76%,75. 93%,78. 81% and 80. 42%,respectively. 展开更多
关键词 automatic control technique laser-induced breakdown spectroscopy(LIBS) measurement and control system(MCS) COMPONENT
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Development and application of the standard for infrared intelligent body temperature measurement system in the normalized COVID-19 prevention and control
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作者 Huang Yong Ren Wenjing 《China Standardization》 2022年第S01期42-46,共5页
In the phase of the normalized COVID-19 prevention and control,non-contact temperature measurement is one of the most efficient and convenient methods for initial screening of suspected cases.In the year of 2020 in Wu... In the phase of the normalized COVID-19 prevention and control,non-contact temperature measurement is one of the most efficient and convenient methods for initial screening of suspected cases.In the year of 2020 in Wuhan,such non-contact equipment was urgently demanded,standards development in the traditional way cannot satisfy the market needs.So,the research and development of this standard for infrared intelligent body temperature measurement system was carried out in a rapid way. 展开更多
关键词 temperature measurement COVID-19 pandemic prevention and control standards development
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A New Device for Gas-Liquid Flow Measurements Relying on Forced Annular Flow
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作者 Tiantian Yu Youping Lv +5 位作者 Hao Zhong Ming Liu Pingyuan Gai Zeju Jiang Peng Zhang Xingkai Zhang 《Fluid Dynamics & Materials Processing》 EI 2024年第8期1759-1772,共14页
A new measurement device,consisting of swirling blades and capsule-shaped throttling elements,is proposed in this study to eliminate typical measurement errors caused by complex flow patterns in gas-liquid flow.The sw... A new measurement device,consisting of swirling blades and capsule-shaped throttling elements,is proposed in this study to eliminate typical measurement errors caused by complex flow patterns in gas-liquid flow.The swirling blades are used to transform the complex flow pattern into a forced annular flow.Drawing on the research of existing blockage flow meters and also exploiting the single-phase flow measurement theory,a formula is introduced to measure the phase-separated flow of gas and liquid.The formula requires the pressure ratio,Lockhart-Martinelli number(L-M number),and the gas phase Froude number.The unknown parameters appearing in the formula are fitted through numerical simulation using computational fluid dynamics(CFD),which involves a comprehensive analysis of the flow field inside the device from multiple perspectives,and takes into account the influence of pressure fluctuations.Finally,the measurement model is validated through an experimental error analysis.The results demonstrate that the measurement error can be maintained within±8%for various flow patterns,including stratified flow,bubble flow,and wave flow. 展开更多
关键词 Gas-liquid flow measurement blocking flowmeter measurement model pressure fluctuations numerical simulation experimental control
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H∞ Measurement-feedback Control for Systems with Input and Measurement Delays
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作者 WANG Hong-Xia ZHANG Huan-Shui 《自动化学报》 EI CSCD 北大核心 2008年第11期1417-1423,共7页
纸专注于与不仅输入延期而且测量延期为系统发现 H 测量反馈控制法律。和伪测量, Krein 空间被介绍以便在我们把原来的问题变换成最小化的以后,重新组织的技术能被利用。最后,我们得到需要的控制器并且看到分离原则也是适用的推迟系... 纸专注于与不仅输入延期而且测量延期为系统发现 H 测量反馈控制法律。和伪测量, Krein 空间被介绍以便在我们把原来的问题变换成最小化的以后,重新组织的技术能被利用。最后,我们得到需要的控制器并且看到分离原则也是适用的推迟系统到某程度。 展开更多
关键词 测量方法 反馈控制系统 测量时滞 自动化系统
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Impact of Migrant Populations on Tuberculosis Rates in Saudi Arabia: Assessing How Migration Patterns Affect TB Incidence and Control Measures: A Narrative Review
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作者 Neda Ali Al Bati 《Journal of Tuberculosis Research》 2024年第3期165-181,共17页
This research focuses on the effects of migration on the TB infection rate and its prevention in Saudi Arabia, which has a large number of expatriates from TB-affected countries. Despite, based on the current global s... This research focuses on the effects of migration on the TB infection rate and its prevention in Saudi Arabia, which has a large number of expatriates from TB-affected countries. Despite, based on the current global statistics of TB occurrence, it is evident that the national incidence of TB has reduced from 10.55 per 100,000 in 2015 to 8.36 per 100,000 in 2019;despite this, there are still some difficulties because migrants bring new strains of Mycobacterium tuberculosis. Hindrances, including language barriers and perceived immigration status, hinder patients from seeking medical attention or doctors from diagnosing diseases. Each patient and each cultural group need special attention to public health, enhancing living circumstances, and health care support. Community participation, inclusion of TB control programs into functional healthcare facilities, and the functioning of TB programs need to be stressed to address TB issues. Considering the focus on social, economic, and cultural approaches, the country can make severe advancements in TB control and population protection. This holistic analysis is critical for a long-term effective strategy to combat TB in the Kingdom. 展开更多
关键词 Kingdom Saudi Arabia (KSA) Tuberculosis (TB) Prevalence MIGRANTS control Measures
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Impact of Forestry Interventions on Groundwater Recharge and Sediment Control in the Ganga River Basin 被引量:1
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作者 Ombir Singh Saswat Kumar Kar Nimmala Mohan Reddy 《Open Journal of Forestry》 2023年第1期13-31,共19页
Water related services of natural infrastructure will help to combat the risk of water crisis, and nature-based solutions involve the management of ecosystems to mimic or optimize the natural processes for the provisi... Water related services of natural infrastructure will help to combat the risk of water crisis, and nature-based solutions involve the management of ecosystems to mimic or optimize the natural processes for the provision and regulation of water. Forested areas provide environmental stability and supply a high proportion of the world’s accessible freshwater for domestic, agricultural, industrial and ecological needs. The present work on “Forestry Interventions for Ganga” to rejuvenate the river is one of the steps toward the Ganga River rejuvenation programme in the country. The consequences of forestry interventions for Ganga will be determined on the basis of water quantity and water quality in the Ganga River. The study conservatively estimated the water savings and sedimentation reduction of the riverscape management in the Ganga basin using the Soil Conservation Service Curve Number (SCS-CN) & GEC, 2015 and Trimble, 1999 & CWC, 2019 methodologies, respectively. Forestry plantations and soil and moisture conservation measures devised in the programme to rejuvenate the Ganga River are expected to increase water recharge and decrease sedimentation load by 231.011 MCM&#183;yr<sup>-1</sup> and 1119.6 cubic m&#183;yr<sup>-1</sup> or 395.20 tons&#183;yr<sup>-1</sup>, respectively, in delineated riverscape area of 83,946 km<sup>2</sup> in Ganga basin due to these interventions. The role of trees and forests in improving hydrologic cycles, soil infiltration and ground water recharge in Ganga basin seems to be the reason for this change. Forest plantations and other bioengineering techniques can help to keep rivers perennial, increase precipitation, prevent soil erosion and mitigate floods, drought & climate change. The bioengineering techniques could be a feasible tool to enhance rivers’ self-purification as well as to make river perennial. The results will give momentum to the National Mission of Clean Ganga (NMCG) and its Namami Gange programme including other important rivers in the country and provide inputs in understanding the linkages among forest structure, function, and streamflow. 展开更多
关键词 Bioengineering Measures Ganga River Basin Sediment control Water Harvesting
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Novel Distance Measures on Hesitant Fuzzy Sets Based on Equal-Probability Transformation and Their Application in Decision Making on Intersection Traffic Control
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作者 Fangwei Zhang Yi Zhao +2 位作者 Jun Ye Shuhong Wang Jingyi Hu 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第5期1589-1602,共14页
The purpose of this study is to reduce the uncertainty in the calculation process on hesitant fuzzy sets(HFSs).The innovation of this study is to unify the cardinal numbers of hesitant fuzzy elements(HFEs)in a special... The purpose of this study is to reduce the uncertainty in the calculation process on hesitant fuzzy sets(HFSs).The innovation of this study is to unify the cardinal numbers of hesitant fuzzy elements(HFEs)in a special way.Firstly,a probability density function is assigned for any given HFE.Thereafter,equal-probability transformation is introduced to transform HFEs with different cardinal numbers on the condition into the same probability density function.The characteristic of this transformation is that the higher the consistency of the membership degrees in HFEs,the higher the credibility of the mentioned membership degrees is,then,the bigger the probability density values for them are.According to this transformation technique,a set of novel distance measures on HFSs is provided.Finally,an illustrative example of intersection traffic control is introduced to show the usefulness of the given distance measures.The example also shows that this study is a good complement to operation theories on HFSs. 展开更多
关键词 Hesitant fuzzy sets equal-probability mapping distance measure intersection traffic control cardinality theory
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Information Security Evaluation of Industrial Control Systems Using Probabilistic Linguistic MCDM Method
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作者 Wenshu Xu Mingwei Lin 《Computers, Materials & Continua》 SCIE EI 2023年第10期199-222,共24页
Industrial control systems(ICSs)are widely used in various fields,and the information security problems of ICSs are increasingly serious.The existing evaluation methods fail to describe the uncertain evaluation inform... Industrial control systems(ICSs)are widely used in various fields,and the information security problems of ICSs are increasingly serious.The existing evaluation methods fail to describe the uncertain evaluation information and group evaluation information of experts.Thus,this paper introduces the probabilistic linguistic term sets(PLTSs)to model the evaluation information of experts.Meanwhile,we propose a probabilistic linguistic multi-criteria decision-making(PL-MCDM)method to solve the information security assessment problem of ICSs.Firstly,we propose a novel subscript equivalence distance measure of PLTSs to improve the existing methods.Secondly,we use the Best Worst Method(BWM)method and Criteria Importance Through Inter-criteria Correlation(CRITIC)method to obtain the subjective weights and objective weights,which are used to derive the combined weights.Thirdly,we use the subscript equivalence distance measure method and the combined weight method to improve the probabilistic linguistic Visekriterijumska Optimizacija I Kompromisno Resenje(PL-VIKOR)method.Finally,we apply the proposed method to solve the information security assessment problem of ICSs.When comparing with the existing methods such as the probabilistic linguistic Tomada deDecisão Iterativa Multicritério(PL-TODIM)method and probabilistic linguistic Technique for Order Preference by Similarity to Ideal Solution(PL-TOPSIS)method,the case example shows that the proposed method can provide more reasonable ranking results.By evaluating and ranking the information security level of different ICSs,managers can identify problems in time and guide their work better. 展开更多
关键词 Multi-criteria decision-making distance measure probabilistic linguistic term sets industrial control system information security assessment
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H-infinity measurement-feedback control for discrete-time systems with a single measurement delay 被引量:1
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作者 Mei LIU Huanshui ZHANG Guangren DUAN 《控制理论与应用(英文版)》 EI 2006年第2期121-127,共7页
H-infinity control problem for linear discrete-time systems with instantaneous and delayed measurements is studied. A necessary and sufficient condition for the existence of the H-infinity controller is derived by app... H-infinity control problem for linear discrete-time systems with instantaneous and delayed measurements is studied. A necessary and sufficient condition for the existence of the H-infinity controller is derived by applying reorganized innovation analysis approach in Krein space. The measurement-feedback controller is designed by performing two Riccati equations. The presented approach does not require the state augmentation. 展开更多
关键词 H-infinity control Delayed measurement Discrete-time systems
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SVD Approach for Actuator and Sensor Placement in Active Vibration Control of Large Cable Net Structures 被引量:1
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作者 Yang Liu Weizhong Zhang Xiuyun Meng 《Journal of Beijing Institute of Technology》 EI CAS 2019年第4期675-686,共12页
The actuator and sensor placement problem for active vibration control of large cable net structures is investigated in this paper.Since the structures exhibit closely spaced modes in the range of low frequencies,the ... The actuator and sensor placement problem for active vibration control of large cable net structures is investigated in this paper.Since the structures exhibit closely spaced modes in the range of low frequencies,the number of modes to be considered is quite large after modal truncation,while only a limited number of actuators and sensors are to be placed.This makes it hard to determine the actuator and sensor locations with the existing placement methods in the literature such as the methods based on the controllability/observability grammian.To deal with this issue,an actuator and sensor placement method based on singular value decompositions(SVD)of the input and output matrices is proposed,which guarantees the modal controllability and observability of the system.The effectiveness of the SVD based method is verified through numerical simulations in which comparisons are conducted between randomly-chosen locations and the optimal ones obtained by a genetic algorithm. 展开更多
关键词 actuator and sensor placement large cable net structures active vibration control
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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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Study on DeviceNet communication mechanism and its application in protection measurement and control system 被引量:1
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作者 佟为明 Li Zhongwei +1 位作者 Sun Fanjin Cheng Shukang 《High Technology Letters》 EI CAS 2007年第1期1-5,共5页
To fit in with the developing requirement of int and communication of protective relays, a protection egrated functions of protection measurement, control measurement and control system based on DeviceNet fieldbus is ... To fit in with the developing requirement of int and communication of protective relays, a protection egrated functions of protection measurement, control measurement and control system based on DeviceNet fieldbus is designed. The communication mechanism of DeviceNet is studied and data trigger modes, communication connection, message types and other key technologies are analyzed. The object modeling and device description of the device are realized too. Results of network test, dynamic simulation and test in the field indicate that this system can accomplish all the communication tasks in real time and can make precise response to every kind of faults of the motor, transformer, line and capacitor. Moreover, this system has higher measurement precision and better control capability. 展开更多
关键词 communication mechanism protection measurement and control system FIELDBUS DEVICENET
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Dynamics of super-quantum discord and direct control with weak measurement in open quantum system
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作者 嵇英华 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第12期209-214,共6页
Super-quantum discord(SQD) with weak measurement is regarded as a kind of quantum correlation in quantum information processing. We compare and analyze the dynamical evolutions of SQD, quantum discord(QD), and qua... Super-quantum discord(SQD) with weak measurement is regarded as a kind of quantum correlation in quantum information processing. We compare and analyze the dynamical evolutions of SQD, quantum discord(QD), and quantum entanglement(QE) between two qubits in the correlated dephasing environmental model. The results indicate that(i) owing to the much smaller influence of weak measurement on the coherence of the system than that of von Neumann projection measurement, SQD with weak measurement is larger than QD, and(ii) dynamical evolution of QD or QE monotonically goes to zero with time, while SQD monotonically tends to a stable value and a freezing phenomenon occurs. The stable value after freezing mainly depends on the measurement strength and the purity of the initial quantum state. 展开更多
关键词 super-quantum discord(SQD) weak measurement control
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Stability and boundedness in terms of two measures for nonlinear impulsive control systems
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作者 Qiang XI 《控制理论与应用(英文版)》 EI 2009年第3期243-247,共5页
In this paper we study stability and boundedness in terms of two measures for impulsive control systems. By using variational Lyapunov method, a new variational comparison principle and some criteria on stability and ... In this paper we study stability and boundedness in terms of two measures for impulsive control systems. By using variational Lyapunov method, a new variational comparison principle and some criteria on stability and boundedness are obtained. An example is presented to illustrate the efficiency of proposed result. 展开更多
关键词 STABILITY BOUNDEDNESS Impulsive control systems Variational Lyapunov method Two measures
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Software Development for Digital Control of WDW Series Testing Machine and Measurement of K_(IC)
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作者 黄兴 马杭 程昌钧 《Journal of Shanghai University(English Edition)》 CAS 2005年第1期58-61,共4页
Software has been developed for digital control of WDW series testing machine and the measurement of fracture toughness by modularized design. Development of the software makes use of multi-thread and serial communica... Software has been developed for digital control of WDW series testing machine and the measurement of fracture toughness by modularized design. Development of the software makes use of multi-thread and serial communication techniques, which can accurately control the testing machine and measure the fracture toughness in real-time. Three-point bending specimens were used in the measurement. The software operates stably and reliably, expanding the function of WDW series testing machine. 展开更多
关键词 testing machine digital control measurement of fracture toughness software development.
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Frame Design and Reality of On-line Quality Control System for CNC Machining Center Based on Microcomputer
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作者 刘晓胜 《High Technology Letters》 EI CAS 1998年第2期26-32,共7页
After giving a short review of the methods used for detecting and monitoring in general systems, this paper describes the way of communication between computer and Computer Numerical Control (CNC) Machining Center (MC... After giving a short review of the methods used for detecting and monitoring in general systems, this paper describes the way of communication between computer and Computer Numerical Control (CNC) Machining Center (MC). Based on these, the paper addresses the means of performing in cycle measurement for manufacturing quality, provides an approach of improving the state of manufacturing process by achieving the real time change of control parameters according to the level of manufacturing process, and discusses the technique of implementing in process dimensional errors compensation corresponding to the in cycle measurement. The results of the experiments show that the frame design is successful and the operation is reliable. The system is taking shape nowadays. 展开更多
关键词 Detection MONITOR Compensation In cycle measurement On line QUALITY control Manufacturing process
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Bayesian Approach to Ranking and Selection for a Binary Measurement System
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作者 Mark Eschmann James D. Stamey +1 位作者 Phil D. Young Dean M. Young 《Open Journal of Statistics》 2019年第4期436-444,共9页
Binary measurement systems that classify parts as either pass or fail are widely used. Inspectors or inspection systems are often subject to error. The error rates are unlikely to be identical across inspectors. We pr... Binary measurement systems that classify parts as either pass or fail are widely used. Inspectors or inspection systems are often subject to error. The error rates are unlikely to be identical across inspectors. We propose a random effects Bayesian approach to model the error probabilities and overall conforming rate. We also introduce a feature-subset selection procedure to determine the best inspector in terms of overall classification accuracy. We provide simulation studies that demonstrate the viability of our proposed estimation ranking and subset-selection methods and apply the methods to a real data set. 展开更多
关键词 BAYESIAN STATISTICS QUALITY control BINARY measurement systems MISCLASSIFICATION
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A measurement system of magnetism parameters for motion control
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作者 王晓明 黄旭艳 雷涛 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2007年第3期297-301,共5页
Magnetism parameters vary with the position and the speed of electromagnetic actuator's motion parts.The measurement unit presented in the paper can be applied to get the position and the speed feedback informatio... Magnetism parameters vary with the position and the speed of electromagnetic actuator's motion parts.The measurement unit presented in the paper can be applied to get the position and the speed feedback information from the measurement of electromagnetism parameters,and can constitute the untouched feedback sensing unit in the closed-loop motion control,and it adapts to the diversified feedback control of electromagnetic actuator.The digital miniaturization meter,based on MSP430 single chip processor,which can do the multi-purpose measurement of Φ & B through the menu selection,can be used for the electromagnetic actuator's performance evaluation and improvement,and also the online quality control in production process.Both real-time data graph and data table can be displayed in the meter.The paper presents the system's structure,describes the principle,discusses the working modes,and shows the software flowchart and the measuring results. 展开更多
关键词 motion control magnetism measurement electromagnetic actuator SENSORLESS
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Global output feedback control of feedforward nonlinear time-delay systems with unknown growth rate and unknown measurement sensitivity
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作者 Weiyong Yu Keao Gao +1 位作者 Hongbing Zhou Qiang Liu 《Control Theory and Technology》 EI CSCD 2024年第1期122-134,共13页
This paper discusses the problem of global state regulation via output feedback for a class of feedforward nonlinear time-delay systems with unknown measurement sensitivity. Different from previous works, the nonlinea... This paper discusses the problem of global state regulation via output feedback for a class of feedforward nonlinear time-delay systems with unknown measurement sensitivity. Different from previous works, the nonlinear terms are dominated by upper triangular linear unmeasured (delayed) states multiplied by unknown growth rate. The unknown growth rate is composed of an unknown constant, a power function of output, and an input function. Furthermore, due to the measurement uncertainty of the system output, it is more difficult to solve this problem. It is proved that the presented output feedback controller can globally regulate all states of the nonlinear systems using the dynamic gain scaling technique and choosing the appropriate Lyapunov–Krasovskii functionals. 展开更多
关键词 Adaptive control Dynamic gain controllers Feedforward time-delay systems measurement sensitivity Output feedback
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