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The development of data acquisition and control system for extraction power supply of prototype RF ion source 被引量:1
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作者 Meichu HUANG Chundong HU +4 位作者 Yuanzhe ZHAO Caichao JIANG Yahong XIE Shiyong CHEN Qinglong CUI 《Plasma Science and Technology》 SCIE EI CAS CSCD 2018年第8期104-111,共8页
A 16 kV/20 A power supply was developed for the extraction grid of prototype radio frequency(RF) ion source of neutral beam injector. To acquire the state signals of extraction grid power supply(EGPS) and control ... A 16 kV/20 A power supply was developed for the extraction grid of prototype radio frequency(RF) ion source of neutral beam injector. To acquire the state signals of extraction grid power supply(EGPS) and control the operation of the EGPS, a data acquisition and control system has been developed. This system mainly consists of interlock protection circuit board, photoelectric conversion circuit, optical fibers, industrial compact peripheral component interconnect(CPCI) computer and host computer. The human machine interface of host computer delivers commands and data to program of the CPCI computer, as well as offers a convenient client for setting parameters and displaying EGPS status. The CPCI computer acquires the status of the power supply. The system can turn-off the EGPS quickly when the faults of EGPS occur. The system has been applied to the EGPS of prototype RF ion source. Test results show that the data acquisition and control system for the EGPS can meet the requirements of the operation of prototype RF ion source. 展开更多
关键词 RF ion source data acquisition control system TCP/IP protocol beam extraction
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Quality Control System of Meteorological Real-time Data from Automatic Weather Stations in Shandong
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作者 ZHOU Xiao-tian CHU Xi WANG Hong 《Meteorological and Environmental Research》 2012年第1期48-50,共3页
The quality control system for meteorological real-time data from automatic weather stations in Shandong realized integration of communi- cation system and provincial quality control system, and an interaction platfor... The quality control system for meteorological real-time data from automatic weather stations in Shandong realized integration of communi- cation system and provincial quality control system, and an interaction platform which was mainly created by Web was set up. The system not only was fully guaranteed for the funning of basic business, also improved the reliability of the data. 展开更多
关键词 Automatic weather stations Real-time data Quality control China
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The Construction and Implementation Path of the Audit System for Quality Control in the Big Data Era
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作者 Wenjun Zou 《Proceedings of Business and Economic Studies》 2023年第6期111-115,共5页
In the era of big data,the construction and implementation of a quality control audit system are particularly crucial.This article delves into the impact of big data technology on quality control auditing,establishes ... In the era of big data,the construction and implementation of a quality control audit system are particularly crucial.This article delves into the impact of big data technology on quality control auditing,establishes a quality control auditing system in the big data era,and elucidates the pathway to realizing this system.Through the application of big data technology to quality control audits,there is an enhancement in audit efficiency,the attainment of more accurate risk assessment,and the provision of robust support for the sustainable development of enterprises. 展开更多
关键词 Big data Quality control Audit system
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A Virtual Router Cluster System Based on the Separation of the Control Plane and the Data Plane
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作者 Kentaro Ogawa 《信息通信技术》 2012年第2期48-53,共6页
This paper proposes a virtual router cluster system based on the separation of the control plane and the data plane from multiple perspectives,such as architecture,key technologies,scenarios and standardization.To som... This paper proposes a virtual router cluster system based on the separation of the control plane and the data plane from multiple perspectives,such as architecture,key technologies,scenarios and standardization.To some extent,the virtual cluster simplifies network topology and management,achieves automatic conFig.uration and saves the IP address.It is a kind of low-cost expansion method of aggregation equipment port density. 展开更多
关键词 摘要 编辑部 编辑工作 读者
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Data-Driven Model Identification and Control of the Inertial Systems
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作者 Irina Cojuhari 《Intelligent Control and Automation》 2023年第1期1-18,共18页
In the synthesis of the control algorithm for complex systems, we are often faced with imprecise or unknown mathematical models of the dynamical systems, or even with problems in finding a mathematical model of the sy... In the synthesis of the control algorithm for complex systems, we are often faced with imprecise or unknown mathematical models of the dynamical systems, or even with problems in finding a mathematical model of the system in the open loop. To tackle these difficulties, an approach of data-driven model identification and control algorithm design based on the maximum stability degree criterion is proposed in this paper. The data-driven model identification procedure supposes the finding of the mathematical model of the system based on the undamped transient response of the closed-loop system. The system is approximated with the inertial model, where the coefficients are calculated based on the values of the critical transfer coefficient, oscillation amplitude and period of the underdamped response of the closed-loop system. The data driven control design supposes that the tuning parameters of the controller are calculated based on the parameters obtained from the previous step of system identification and there are presented the expressions for the calculation of the tuning parameters. The obtained results of data-driven model identification and algorithm for synthesis the controller were verified by computer simulation. 展开更多
关键词 data-Driven Model Identification controller Tuning Undamped Transient Response Closed-Loop system Identification PID controller
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Cross-Domain Bilateral Access Control on Blockchain-Cloud Based Data Trading System
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作者 Youngho Park Su Jin Shin Sang Uk Shin 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第10期671-688,共18页
Data trading enables data owners and data requesters to sell and purchase data.With the emergence of blockchain technology,research on blockchain-based data trading systems is receiving a lot of attention.Particularly... Data trading enables data owners and data requesters to sell and purchase data.With the emergence of blockchain technology,research on blockchain-based data trading systems is receiving a lot of attention.Particularly,to reduce the on-chain storage cost,a novel paradigm of blockchain and cloud fusion has been widely considered as a promising data trading platform.Moreover,the fact that data can be used for commercial purposes will encourage users and organizations from various fields to participate in the data marketplace.In the data marketplace,it is a challenge how to trade the data securely outsourced to the external cloud in a way that restricts access to the data only to authorized users across multiple domains.In this paper,we propose a cross-domain bilateral access control protocol for blockchain-cloud based data trading systems.We consider a system model that consists of domain authorities,data senders,data receivers,a blockchain layer,and a cloud provider.The proposed protocol enables access control and source identification of the outsourced data by leveraging identity-based cryptographic techniques.In the proposed protocol,the outsourced data of the sender is encrypted under the target receiver’s identity,and the cloud provider performs policy-match verification on the authorization tags of the sender and receiver generated by the identity-based signature scheme.Therefore,data trading can be achieved only if the identities of the data sender and receiver simultaneously meet the policies specified by each other.To demonstrate efficiency,we evaluate the performance of the proposed protocol and compare it with existing studies. 展开更多
关键词 Bilateral access control blockchain data sharing policy-match
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Enhancing Patients Outcomes and Infection Control through Smart Indoor Air Quality Monitoring Systems
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作者 Othniel Ojochonu Abalaka Joe Essien +1 位作者 Calistus Chimezie Martin Ogharandukun 《Journal of Computer and Communications》 2024年第6期25-37,共13页
Air pollution poses a critical threat to public health and environmental sustainability globally, and Nigeria is no exception. Despite significant economic growth and urban development, Nigeria faces substantial air q... Air pollution poses a critical threat to public health and environmental sustainability globally, and Nigeria is no exception. Despite significant economic growth and urban development, Nigeria faces substantial air quality challenges, particularly in urban centers. While outdoor air pollution has received considerable attention, the issue of indoor air quality remains underexplored yet equally critical. This study aims to develop a reliable, cost-effective, and user-friendly solution for continuous monitoring and reporting of indoor air quality, accessible from anywhere via a web interface. Addressing the urgent need for effective indoor air quality monitoring in urban hospitals, the research focuses on designing and implementing a smart indoor air quality monitoring system using Arduino technology. Employing an Arduino Uno, ESP8266 Wi-Fi module, and MQ135 gas sensor, the system collects real-time air quality data, transmits it to the ThingSpeak cloud platform, and visualizes it through a user-friendly web interface. This project offers a cost-effective, portable, and reliable solution for monitoring indoor air quality, aiming to mitigate health risks and promote a healthier living environment. 展开更多
关键词 Artificial Intelligence Air Pollution Infection control data Transmission data Acquisition SENSORS
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Evaluation of Two Momentum Control Variable Schemes and Their Impact on the Variational Assimilation of Radar Wind Data:Case Study of a Squall Line 被引量:10
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作者 Xin LI Mingjian ZENG +3 位作者 Yuan WANG Wenlan WANG Haiying WU Haixia MEI 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2016年第10期1143-1157,共15页
Different choices of control variables in variational assimilation can bring about different influences on the analyzed atmospheric state. Based on the WRF model's three-dimensional variational assimilation system, t... Different choices of control variables in variational assimilation can bring about different influences on the analyzed atmospheric state. Based on the WRF model's three-dimensional variational assimilation system, this study compares the be- havior of two momentum control variable options-streamfunction velocity potential (ψ-χ) and horizontal wind components (U-V)-in radar wind data assimilation for a squall line case that occurred in Jiangsu Province on 24 August 2014. The wind increment from the single observation test shows that the ψ-χ control variable scheme produces negative increments in the neighborhood around the observation point because streamfunction and velocity potential preserve integrals of velocity. On the contrary, the U-V control variable scheme objectively reflects the information of the observation itself. Furthermore, radial velocity data from 17 Doppler radars in eastern China are assimilated. As compared to the impact of conventional observation, the assimilation of radar radial velocity based on the U-V control variable scheme significantly improves the mesoscale dynamic field in the initial condition. The enhanced low-level jet stream, water vapor convergence and low-level wind shear result in better squall line forecasting. However, the ψ-χ control variable scheme generates a discontinuous wind field and unrealistic convergence/divergence in the analyzed field, which lead to a degraded precipitation forecast. 展开更多
关键词 three-dimensional variational assimilation momentum control variable Doppler radar data squall line
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Analysis of the Impact of Big Data Technology on Environmental Pollution Control Audit
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作者 Xianrui Yang Jinyu Liu 《Proceedings of Business and Economic Studies》 2024年第3期22-27,共6页
As China strives towards the second centenary goal,increasing attention is being paid to environmental pollution and other related issues.Concurrently,with the rapid development of big data technology,many big data so... As China strives towards the second centenary goal,increasing attention is being paid to environmental pollution and other related issues.Concurrently,with the rapid development of big data technology,many big data solutions have been applied to environmental pollution control audits,exerting a significant impact.This paper presents the current situation of environmental pollution audits,summarizing the application of big data from the perspectives of both domestic and international research.In terms of data collection and data analysis for environmental pollution audits,cloud platform technology,and visualization technology are selected based on multiple data sources.The impact in the field of environmental pollution control audits is further analyzed.It is found that the environmental pollution audit cloud platform is not yet perfect,the technical skills of audit personnel are insufficient,and some technologies are not mature.Relevant suggestions are put forward to provide a reference for the future development of big data technology and its integration with environmental pollution control audits. 展开更多
关键词 Big data technology Environmental pollution control AUDIT
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A PRELIMINARY STUDY ON THE QUALITY CONTROL METHOD FOR GUANGDONG GPS/PWV DATA AND ITS EFFECTS ON PRECIPITATION FORECASTS IN ITS ANNUALLY FIRST RAINING SEASON 被引量:3
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作者 李昊睿 丁伟钰 +3 位作者 薛纪善 高郁东 张旭斌 黄华栋 《Journal of Tropical Meteorology》 SCIE 2016年第4期535-543,共9页
We first analyzed GPS precipitable water vapor(GPS/PWV) available from a ground-based GPS observation network in Guangdong from 1 August 2009 to 27 August 2012 and then developed a method of quality control before GPS... We first analyzed GPS precipitable water vapor(GPS/PWV) available from a ground-based GPS observation network in Guangdong from 1 August 2009 to 27 August 2012 and then developed a method of quality control before GPS/PWV data is assimilated into the GRAPES 3DVAR system. This method can reject the outliers effectively. After establishing the criterion for quality control, we did three numerical experiments to investigate the impact on the precipitation forecast with and without the quality-controlled GPS/PWV data before they are assimilated into the system.In the numerical experiments, two precipitation cases(on 6 to 7 May, 2010 and 27 to 28 April, 2012 respectively) that occurred in the annually first raining season of Guangdong were selected. The results indicated that after quality control,only the GPS/PWV data that deviates little from the NCEP/PWV data can be assimilated into the system, has reasonable adjustment of the initial water vapor above Guangdong, and eventually improves the intensity and location of 24-h precipitation forecast significantly. 展开更多
关键词 GRAPES 3DVAR quality control data assimilation GPS precipitable water vapor
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Fault detection observer design for networked control system with long time-delays and data packet dropout 被引量:3
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作者 Xuan Li Xiaobei Wu +1 位作者 Zhiliang Xu Cheng Huang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2010年第5期877-882,共6页
Focusing on the networked control system with long time-delays and data packet dropout,the problem of observerbased fault detection of the system is studied.According to conditions of data arrival of the controller,th... Focusing on the networked control system with long time-delays and data packet dropout,the problem of observerbased fault detection of the system is studied.According to conditions of data arrival of the controller,the state observers of the system are designed to detect faults when they occur in the system.When the system is normal,the observers system is modeled as an uncertain switched system.Based on the model,stability condition of the whole system is given.When conditions are satisfied,the system is asymptotically stable.When a fault occurs,the observers residual can change rapidly to detect the fault.A numerical example shows the effectiveness of the proposed method. 展开更多
关键词 networked control system fault detection long timedelays data packet dropout.
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Stochastic stability of networked control systems with network-induced delay and data dropout 被引量:3
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作者 Xiaomei ZHANG Yufan ZHENG Guoping LU 《控制理论与应用(英文版)》 EI 2008年第4期405-409,共5页
This paper deals with the stochastic stability of networked control systems with the presence of network- induced delay and transmitted data dropout. Based on the Lyapunov approach, sufficient conditions for the mean-... This paper deals with the stochastic stability of networked control systems with the presence of network- induced delay and transmitted data dropout. Based on the Lyapunov approach, sufficient conditions for the mean-square stability of the networked control system are derived subject that the sequence of transmission interval is driven by an identically independently distributed sequence and by a finite state Markov chain, respectively. Stabilization controllers are constructed in terms of linear matrix inequalities correspondingly. An example is provided to illustrate our results. 展开更多
关键词 Networked control systems Network-induced delay data dropout Lyapunov method Linear matrix inequalities
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Controller design for networked control system with data packet dropout and transmission delays 被引量:2
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作者 Xinping GUAN Shuangfeng DAI Chengnian LONG 《控制理论与应用(英文版)》 EI 2007年第3期227-232,共6页
In this paper, the stabilization problem for a class of networked control systems (NCSs) with data packet dropouts and transmission time delays is considered, where the delays are time-varying and uncertain, the dat... In this paper, the stabilization problem for a class of networked control systems (NCSs) with data packet dropouts and transmission time delays is considered, where the delays are time-varying and uncertain, the data packet dropout is modeled as a two-state Markov chain. To compensate the lost packet, a data packet dropout compensator is established. Thus a more realistic model for such NCSs is presented. Sufficient conditions for the stabilization of the new resulting system are derived in the form of linear matrix inequalities (LMIs). Numerical example illustrates the solvability and effectiveness of the results. 展开更多
关键词 Networked control system Network-induced time delays data packet dropout Markov chain Linear matrix inequalities
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Security and Privacy Frameworks for Access Control Big Data Systems 被引量:2
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作者 Paolina Centonze 《Computers, Materials & Continua》 SCIE EI 2019年第5期361-374,共14页
In the security and privacy fields,Access Control(AC)systems are viewed as the fundamental aspects of networking security mechanisms.Enforcing AC becomes even more challenging when researchers and data analysts have t... In the security and privacy fields,Access Control(AC)systems are viewed as the fundamental aspects of networking security mechanisms.Enforcing AC becomes even more challenging when researchers and data analysts have to analyze complex and distributed Big Data(BD)processing cluster frameworks,which are adopted to manage yottabyte of unstructured sensitive data.For instance,Big Data systems’privacy and security restrictions are most likely to failure due to the malformed AC policy configurations.Furthermore,BD systems were initially developed toped to take care of some of the DB issues to address BD challenges and many of these dealt with the“three Vs”(Velocity,Volume,and Variety)attributes,without planning security consideration,which are considered to be patch work.Some of the BD“three Vs”characteristics,such as distributed computing,fragment,redundant data and node-to node communication,each with its own security challenges,complicate even more the applicability of AC in BD.This paper gives an overview of the latest security and privacy challenges in BD AC systems.Furthermore,it analyzes and compares some of the latest AC research frameworks to reduce privacy and security issues in distributed BD systems,which very few enforce AC in a cost-effective and in a timely manner.Moreover,this work discusses some of the future research methodologies and improvements for BD AC systems.This study is valuable asset for Artificial Intelligence(AI)researchers,DB developers and DB analysts who need the latest AC security and privacy research perspective before using and/or improving a current BD AC framework. 展开更多
关键词 Big data access control distributed systems SECURITY PRIVACY
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Achieving Fine-Grained and Flexible Access Control on Blockchain-Based Data Sharing for the Internet of Things 被引量:2
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作者 Ruimiao Wang Xiaodong Wang +2 位作者 Wenti Yang Shuai Yuan Zhitao Guan 《China Communications》 SCIE CSCD 2022年第6期22-34,共13页
The traditional centralized data sharing systems have potential risks such as single point of failures and excessive working load on the central node.As a distributed and collaborative alternative,approaches based upo... The traditional centralized data sharing systems have potential risks such as single point of failures and excessive working load on the central node.As a distributed and collaborative alternative,approaches based upon blockchain have been explored recently for Internet of Things(IoTs).However,the access from a legitimate user may be denied without the pre-defined policy and data update on the blockchain could be costly to the owners.In this paper,we first address these issues by incorporating the Accountable Subgroup Multi-Signature(ASM)algorithm into the Attribute-based Access Control(ABAC)method with Policy Smart Contract,to provide a finegrained and flexible solution.Next,we propose a policy-based Chameleon Hash algorithm that allows the data to be updated in a reliable and convenient way by the authorized users.Finally,we evaluate our work by comparing its performance with the benchmarks.The results demonstrate significant improvement on the effectiveness and efficiency. 展开更多
关键词 blockchain access control smart contract MULTI-SIGNATURE chameleon-hash data sharing Internet of Things
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Single Mobile Sink Based Energy Efficiency and Fast Data Gathering Protocol for Wireless Sensor Networks 被引量:1
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作者 Shivkumar S. Jawaligi G. S. Biradar 《Wireless Sensor Network》 2017年第4期117-144,共28页
Recently, the exponential rise in communication system demands has motivated global academia-industry to develop efficient communication technologies to fulfill energy efficiency and Quality of Service (QoS) demands. ... Recently, the exponential rise in communication system demands has motivated global academia-industry to develop efficient communication technologies to fulfill energy efficiency and Quality of Service (QoS) demands. Wireless Sensor Network (WSN) being one of the most efficient technologies possesses immense potential to serve major communication purposes including civil, defense and industrial purposes etc. The inclusion of sensor-mobility with WSN has broadened application horizon. The effectiveness of WSNs can be characterized by its ability to perform efficient data gathering and transmission to the base station for decision process. Clustering based routing scheme has been one of the dominating techniques for WSN systems;however key issues like, cluster formation, selection of the number of clusters and cluster heads, and data transmission decision from sensors to the mobile sink have always been an open research area. In this paper, a robust and energy efficient single mobile sink based WSN data gathering protocol is proposed. Unlike existing approaches, an enhanced centralized clustering model is developed on the basis of expectation-maximization (EEM) concept. Further, it is strengthened by using an optimal cluster count estimation technique that ensures that the number of clusters in the network region doesn’t introduce unwanted energy exhaustion. Meanwhile, the relative distance between sensor node and cluster head as well as mobile sink is used to make transmission (path) decision. Results exhibit that the proposed EEM based clustering with optimal cluster selection and optimal dynamic transmission decision enables higher throughput, fast data gathering, minima delay and energy consumption, and higher 展开更多
关键词 Wireless Sensor Network data gathering SINGLE Mobile SINK NODE CENTRALIZED Clustering EXPECTATION-MAXIMIZATION
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Separate Dimming Controlling and Data Transmission for an Indoor Visible Light Communication System 被引量:2
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作者 LIU Xiang YANG Aiying +1 位作者 LI Yankun FENG Lihui 《China Communications》 SCIE CSCD 2015年第3期71-76,共6页
Simultaneous dimming controlling and data transmission are usually required in a white LED based indoor visible light communication system.However,the diming controlling of LED normally interferes the data transmissio... Simultaneous dimming controlling and data transmission are usually required in a white LED based indoor visible light communication system.However,the diming controlling of LED normally interferes the data transmission due to the modulation nonlinearity of LED.In order to solve this problem,a scheme by separating the LEDs for the functions of dimming control and data transmission respectively is proposed in this paper.In the scheme,the LEDs used for dimming control function are driven by a dc amplified circuit,and the LEDs for data transmission are driven by a digital modulation circuit respectively.In this way,the modulation distortion to the data signal caused by the modulation nonlinearity can be avoided even if the dimming is at high level dc driven current.The proof-of-concept experiment of a 2.5Mbit/s visible light communication system demonstrates that the dimming controlling and data transmission can be realized simultaneously in a simple way,and the data transmission is not affected by the dimming controlling function.Compared to previous methods,the scheme in this paper is simpler and cost effective,and makes sense when high rate data is transmitted in a visible light communication system. 展开更多
关键词 visible light communication light emitting diode diming controlling data transmission
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Model-based predictive controller design for a class of nonlinear networked systems with communication delays and data loss
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作者 安宝冉 刘国平 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第8期211-216,共6页
This paper discusses the model-based predictive controller design of networked nonlinear systems with communica- tion delay and data loss. Based on the analysis of the closed-loop networked predictive control systems,... This paper discusses the model-based predictive controller design of networked nonlinear systems with communica- tion delay and data loss. Based on the analysis of the closed-loop networked predictive control systems, the model-based networked predictive control strategy can compensate for communication delay and data loss in an active way. The designed model-based predictive controller can also guarantee the stability of the closed-loop networked system. The simulation re- suits demonstrate the feasibility and efficacy of the proposed model-based predictive controller design scheme. 展开更多
关键词 communication delays data loss model-based networked predictive control
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Robust H_∞ control of piecewise-linear chaotic systems with random data loss
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作者 张洪斌 于永斌 张健 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第8期191-199,共9页
This paper studies the problem of robust H∞ control of piecewise-linear chaotic systems with random data loss. The communication links between the plant and the controller are assumed to be imperfect (that is, data ... This paper studies the problem of robust H∞ control of piecewise-linear chaotic systems with random data loss. The communication links between the plant and the controller are assumed to be imperfect (that is, data loss occurs intermittently, which appears typically in a network environment). The data loss is modelled as a random process which obeys a Bernoulli distribution. In the face of random data loss, a piecewise controller is designed to robustly stabilize the networked system in the sense of mean square and also achieve a prescribed H∞ disturbance attenuation performance based on a piecewise-quadratic Lyapunov function. The required H∞ controllers can be designed by solving a set of linear matrix inequalities (LMIs). Chua's system is provided to illustrate the usefulness and applicability of the developed theoretical results. 展开更多
关键词 CHAOS H∞ control piecewise-linear systems piecewise-quadratic Lyapunov functions random data loss
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Closing the loop between data mining and fast decision support for intelligent train scheduling and traffic control
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作者 Ingo A. HANSEN 《北京交通大学学报》 CAS CSCD 北大核心 2019年第1期24-30,共7页
The existing Big Data of transport flows and railway operations can be mined through advanced statistical analysis and machine learning methods in order to describe and predict well the train speed, punctuality, track... The existing Big Data of transport flows and railway operations can be mined through advanced statistical analysis and machine learning methods in order to describe and predict well the train speed, punctuality, track capacity and energy consumption. The accurate modelling of the real spatial and temporal distribution of line and network transport, traffic and performance stimulates a faster construction and implementation of robust and resilient timetables, as well as the development of efficient decision support tools for real-time rescheduling of train schedules. In combination with advanced train control and safety systems even (semi-.) automatic piloting of trains on main and regional railway lines will become feasible in near future. 展开更多
关键词 INTELLIGENT TRAIN RESCHEDULING TRAIN control BIG railway data statistical learning robust TIMETABLING
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