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Design, Analysis and Real-time Implementation of Networked Predictive Control Systems 被引量:6
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作者 LIU Guo-Ping SUN Jian ZHAO Yun-Bo 《自动化学报》 EI CSCD 北大核心 2013年第11期1769-1777,共9页
这份报纸用预兆的控制策略涉及设计,分析和联网的控制系统的即时实现。联网的控制系统的特征的分析被详细说明,它证明一个联网的控制系统与常规控制系统不同。完成靠近环的联网的控制系统的需要的性能,联网的预兆的控制计划被介绍。... 这份报纸用预兆的控制策略涉及设计,分析和联网的控制系统的即时实现。联网的控制系统的特征的分析被详细说明,它证明一个联网的控制系统与常规控制系统不同。完成靠近环的联网的控制系统的需要的性能,联网的预兆的控制计划被介绍。设计,稳定性分析和联网的预兆的控制系统的即时实现被学习。它被联网的预兆的控制计划能补偿随机的网络通讯延期和数据退学学生的模拟和实际实验说明,完成需要的控制性能并且有好靠近环的稳定性。 展开更多
关键词 闭环网络控制系统 预测控制系统 实时实现 设计 预测控制策略 控制方案 网络预测 控制性能
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A Real-Time TCP Stream Reassembly Mechanism in High-Speed Network 被引量:3
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作者 熊兵 陈晓苏 陈宁 《Journal of Southwest Jiaotong University(English Edition)》 2009年第3期185-191,共7页
With the continual growth of the variety and complexity of network crime means, the traditional packet feature matching cannot detect all kinds of intrusion behaviors completely. It is urgent to reassemble network str... With the continual growth of the variety and complexity of network crime means, the traditional packet feature matching cannot detect all kinds of intrusion behaviors completely. It is urgent to reassemble network stream to perform packet processing at a semantic level above the network layer. This paper presents an efficient TCP stream reassembly mechanism for real-time processing of high-speed network traffic. By analyzing the characteristics of network stream in high-speed network and TCP connection establishment process, several polices for designing the reassembly mechanism are built. Then, the reassembly implementation is elaborated in accordance with the policies. Finally, the reassembly mechanism is compared with the traditional reassembly mechanism by the network traffic captured in a typical gigabit gateway. Experiment results illustrate that the reassembly mechanism is efficient and can satisfy the real-time property requirement of traffic analysis system in high-speed network. 展开更多
关键词 TCP stream reassembly High-speed network real-time property Reassembly policy
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Modeling and Statistical Properties Research on Online Real-Time Information Transmission Network 被引量:2
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作者 Guangming Deng Zhen Jia 《Open Journal of Applied Sciences》 2014年第5期234-241,共8页
In this paper, the model of the online real-time information transmission network, such as wechat, micro-blog, and QQ network, is proposed and built, based on the connection properties between users of the online real... In this paper, the model of the online real-time information transmission network, such as wechat, micro-blog, and QQ network, is proposed and built, based on the connection properties between users of the online real-time information transmission network, and combined with the local world evolving characteristics in complex network, then the statistical topological properties of the network is obtained by numerical simulation. Furthermore, we simulated the process of information transmission on the network, according to the actual characteristics of the online real-time information transmission. Statistics show that the degree distribution presents the characteristics of scale free network, presenting power law distribution, while the average path length, the average clustering coefficient and the average size of the network also has a power-law relationship, moreover, the model parameters has no effect on power-law exponent. The spread of information on the network represents obvious fluctuation scaling, reflecting the characteristics that information transmission fluctuates over time. 展开更多
关键词 network INFORMATION TRANSMISSION real-time INFORMATION FLUCTUATION SCALING
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Verification of Real-Time Pricing Systems Based on Probabilistic Boolean Networks
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作者 Koichi Kobayashi Kunihiko Hiraishi 《Applied Mathematics》 2016年第15期1734-1747,共15页
In this paper, verification of real-time pricing systems of electricity is considered using a probabilistic Boolean network (PBN). In real-time pricing systems, electricity conservation is achieved by manipulating the... In this paper, verification of real-time pricing systems of electricity is considered using a probabilistic Boolean network (PBN). In real-time pricing systems, electricity conservation is achieved by manipulating the electricity price at each time. A PBN is widely used as a model of complex systems, and is appropriate as a model of real-time pricing systems. Using the PBN-based model, real-time pricing systems can be quantitatively analyzed. In this paper, we propose a verification method of real-time pricing systems using the PBN-based model and the probabilistic model checker PRISM. First, the PBN-based model is derived. Next, the reachability problem, which is one of the typical verification problems, is formulated, and a solution method is derived. Finally, the effectiveness of the proposed method is presented by a numerical example. 展开更多
关键词 Model Checking Probabilistic Boolean networks real-time Pricing
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Influences of Network Delay on Quality of Experience for Soft Objects in Networked Real-Time Game with Haptic Sense
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作者 Mya Sithu Yutaka Ishibashi +1 位作者 Pingguo Huang Norishige Fukushima 《International Journal of Communications, Network and System Sciences》 2015年第11期440-445,共6页
In this paper, we investigate the influences of network delay on QoE (Quality of Experience) such as the operability of haptic interface device and the fairness between players for soft objects in a networked real-tim... In this paper, we investigate the influences of network delay on QoE (Quality of Experience) such as the operability of haptic interface device and the fairness between players for soft objects in a networked real-time game subjectively and objectively. We handle a networked balloon bursting game in which two players burst balloons (i.e., soft objects) in a 3D virtual space by using haptic interface devices, and the players compete for the number of burst balloons. As a result, we find that the operability depends on the network delay from the local terminal to the other terminal, and the fairness is mainly dependent on the difference in network delay between the players’ terminals. We confirm that there exists a trade-off relationship between the operability and the fairness. We also see that the contribution of the fairness is larger than that of the operability to the comprehensive quality (i.e., the weighted sum of the operability and fairness). Assessment results further show that the output timing of terminals should be adjusted to the terminal which has the latest output timing to maintain the fairness when the difference in network delay between the terminals is large. In this way, the comprehensive quality at each terminal can be maintained as high as possible. 展开更多
关键词 networkED real-time GAME Virtual Environment Balloon BURSTING GAME HAPTIC Interface Devices network Delay Quality of Experience OPERABILITY Fairness
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Contention-Based Beaconless Real-Time Routing Protocol for Wireless Sensor Networks
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作者 Chao Huang Guoli Wang 《Wireless Sensor Network》 2010年第7期528-537,共10页
This paper presents a novel real-time routing protocol, called CBRR, with less energy consumption for wireless sensor networks (WSNs). End-to-End real-time requirements are fulfilled with speed or delay constraint at ... This paper presents a novel real-time routing protocol, called CBRR, with less energy consumption for wireless sensor networks (WSNs). End-to-End real-time requirements are fulfilled with speed or delay constraint at each hop through integrating the contention and neighbor table mechanisms. More precisely, CBRR maintains a neighbor table via the contention mechanism being dependent on wireless broadcast instead of beacons. Comprehensive simulations show that CBRR can not only achieve higher performance in static networks, but also work well for dynamic networks. 展开更多
关键词 Wireless Sensor network real-time Routing Protocol Contention-Based Scheme Beaconless
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A CNN-Based Single-Stage Occlusion Real-Time Target Detection Method
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作者 Liang Liu Nan Yang +4 位作者 Saifei Liu Yuanyuan Cao Shuowen Tian Tiancheng Liu Xun Zhao 《Journal of Intelligent Learning Systems and Applications》 2024年第1期1-11,共11页
Aiming at the problem of low accuracy of traditional target detection methods for target detection in endoscopes in substation environments, a CNN-based real-time detection method for masked targets is proposed. The m... Aiming at the problem of low accuracy of traditional target detection methods for target detection in endoscopes in substation environments, a CNN-based real-time detection method for masked targets is proposed. The method adopts the overall design of backbone network, detection network and algorithmic parameter optimisation method, completes the model training on the self-constructed occlusion target dataset, and adopts the multi-scale perception method for target detection. The HNM algorithm is used to screen positive and negative samples during the training process, and the NMS algorithm is used to post-process the prediction results during the detection process to improve the detection efficiency. After experimental validation, the obtained model has the multi-class average predicted value (mAP) of the dataset. It has general advantages over traditional target detection methods. The detection time of a single target on FDDB dataset is 39 ms, which can meet the need of real-time target detection. In addition, the project team has successfully deployed the method into substations and put it into use in many places in Beijing, which is important for achieving the anomaly of occlusion target detection. 展开更多
关键词 real-time Mask Target CNN (Convolutional Neural network) Single-Stage Detection Multi-Scale Feature Perception
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A Novel Real-Time Fault Diagnostic System for Steam Turbine Generator Set by Using Strata Hierarchical Artificial Neural Network
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作者 Changfeng YAN Hao ZHANG Lixiao WU 《Energy and Power Engineering》 2009年第1期7-16,共10页
The real-time fault diagnosis system is very great important for steam turbine generator set due to a serious fault results in a reduced amount of electricity supply in power plant. A novel real-time fault diagnosis s... The real-time fault diagnosis system is very great important for steam turbine generator set due to a serious fault results in a reduced amount of electricity supply in power plant. A novel real-time fault diagnosis system is proposed by using strata hierarchical fuzzy CMAC neural network. A framework of the fault diagnosis system is described. Hierarchical fault diagnostic structure is discussed in detail. The model of a novel fault diagnosis system by using fuzzy CMAC are built and analyzed. A case of the diagnosis is simulated. The results show that the real-time fault diagnostic system is of high accuracy, quick convergence, and high noise rejection. It is also found that this model is feasible in real-time fault diagnosis. 展开更多
关键词 real-time FAULT diagnosis STRATA HIERARCHICAL artificial neural network fuzzy CMAC
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A Survey on Real-Time MAC Protocols in Wireless Sensor Networks
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作者 Zheng Teng Ki-Il Kim 《Communications and Network》 2010年第2期104-112,共9页
As wireless sensor network becomes pervasive, new requirements have been continuously emerged. How-ever, the most of research efforts in wireless sensor network are focused on energy problem since the nodes are usuall... As wireless sensor network becomes pervasive, new requirements have been continuously emerged. How-ever, the most of research efforts in wireless sensor network are focused on energy problem since the nodes are usually battery-powered. Among these requirements, real-time communication is one of the big research challenges in wireless sensor networks because most of query messages carry time information. To meet this requirement, recently several real-time medium access control protocols have been proposed for wireless sensor networks in the literature because waiting time to share medium on each node is one of main source for end-to-end delay. In this paper, we first introduce the specific requirement of wireless sensor real-time MAC protocol. Then, a collection of recent wireless sensor real-time MAC protocols are surveyed, classified, and described emphasizing their advantages and disadvantages whenever possible. Finally we present a dis-cussion about the challenges of current wireless sensor real-time MAC protocols in the literature, and show the conclusion in the end. 展开更多
关键词 WIRELESS Sensor networks MEDIUM ACCESS Control (MAC) real-time
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On-Line Real Time Realization and Application of Adaptive Fuzzy Inference Neural Network
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作者 Han, Jianguo Guo, Junchao Zhao, Qian 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2000年第1期67-74,共8页
In this paper, a modeling algorithm developed by transferring the adaptive fuzzy inference neural network into an on-line real time algorithm, combining the algorithm with conventional system identification method and... In this paper, a modeling algorithm developed by transferring the adaptive fuzzy inference neural network into an on-line real time algorithm, combining the algorithm with conventional system identification method and applying them to separate identification of nonlinear multi-variable systems is introduced and discussed. 展开更多
关键词 Fuzzy control Identification (control systems) Inference engines Learning algorithms Mathematical models Multivariable control systems Neural networks Nonlinear control systems real time systems
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Cyber Resilience through Real-Time Threat Analysis in Information Security
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作者 Aparna Gadhi Ragha Madhavi Gondu +1 位作者 Hitendra Chaudhary Olatunde Abiona 《International Journal of Communications, Network and System Sciences》 2024年第4期51-67,共17页
This paper examines how cybersecurity is developing and how it relates to more conventional information security. Although information security and cyber security are sometimes used synonymously, this study contends t... This paper examines how cybersecurity is developing and how it relates to more conventional information security. Although information security and cyber security are sometimes used synonymously, this study contends that they are not the same. The concept of cyber security is explored, which goes beyond protecting information resources to include a wider variety of assets, including people [1]. Protecting information assets is the main goal of traditional information security, with consideration to the human element and how people fit into the security process. On the other hand, cyber security adds a new level of complexity, as people might unintentionally contribute to or become targets of cyberattacks. This aspect presents moral questions since it is becoming more widely accepted that society has a duty to protect weaker members of society, including children [1]. The study emphasizes how important cyber security is on a larger scale, with many countries creating plans and laws to counteract cyberattacks. Nevertheless, a lot of these sources frequently neglect to define the differences or the relationship between information security and cyber security [1]. The paper focus on differentiating between cybersecurity and information security on a larger scale. The study also highlights other areas of cybersecurity which includes defending people, social norms, and vital infrastructure from threats that arise from online in addition to information and technology protection. It contends that ethical issues and the human factor are becoming more and more important in protecting assets in the digital age, and that cyber security is a paradigm shift in this regard [1]. 展开更多
关键词 Cybersecurity Information Security network Security Cyber Resilience real-time Threat Analysis Cyber Threats Cyberattacks Threat Intelligence Machine Learning Artificial Intelligence Threat Detection Threat Mitigation Risk Assessment Vulnerability Management Incident Response Security Orchestration Automation Threat Landscape Cyber-Physical Systems Critical Infrastructure Data Protection Privacy Compliance Regulations Policy Ethics CYBERCRIME Threat Actors Threat Modeling Security Architecture
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符合Real-time CORBA规范的传感器网络监控系统设计 被引量:1
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作者 魏云华 《计算机工程与设计》 CSCD 北大核心 2006年第23期4585-4588,4591,共5页
传感器网络在解决底层数据源和I/O设备的异构性、处理连续查询的实时性、服务质量自适应等方面提出了许多新的挑战。提出一种基于实时CORBA的传感器网络数据流处理框架,说明了符合实时中间件规范的数据流处理系统设计的方法和特点,通过... 传感器网络在解决底层数据源和I/O设备的异构性、处理连续查询的实时性、服务质量自适应等方面提出了许多新的挑战。提出一种基于实时CORBA的传感器网络数据流处理框架,说明了符合实时中间件规范的数据流处理系统设计的方法和特点,通过实验对该框架进行了性能测试,验证了其处理连续查询的实时性。 展开更多
关键词 实时中间件 数据流 连续查询 服务质量 传感器网络 实时CORBA
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Real-time Performance Evaluation of Line Topology Switched Ethernet 被引量:4
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作者 Fan Cen Tao Xing Ke-Tong Wu 《International Journal of Automation and computing》 EI 2008年第4期376-380,共5页
Recently,switched Ethernet has become an active area of research because of its wide uses in industry.However,its uses have various real-time constraints on data communications.This paper analyzes the performance of t... Recently,switched Ethernet has become an active area of research because of its wide uses in industry.However,its uses have various real-time constraints on data communications.This paper analyzes the performance of the line topology switched Ethernet as a data acquisition network.Network calculus theory,which has been successfully applied to assess the real-time performance of packet-switched networks,is used to analyze the networks.To properly describe the activity of switches,a novel approach of modeling data flows into or out of switches is addressed.Based on our model,a concisely analytical expression of the maximal end-to-end delay in line topology switched Ethernet is derived.Finally,the relative simulation results are demonstrated.These results agree well with the analytical results,and thus they validate the data flow modeling techniques. 展开更多
关键词 Switched Ethernet network calculus end-to-end delay line topology real-time network.
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Real-Time Method for Detecting Harmonic and Reactive Currents of Single-Phase Circuits 被引量:1
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作者 张秀峰 丁菊霞 《Journal of Southwest Jiaotong University(English Edition)》 2006年第2期135-141,共7页
According to the characteristics of single-phase circuits and demand of using active filter for real-time detecting harmonic and reactive currents, a detecting method based on Fryze's power definition is proposed. Th... According to the characteristics of single-phase circuits and demand of using active filter for real-time detecting harmonic and reactive currents, a detecting method based on Fryze's power definition is proposed. The results of theoretical analysis and simula- tion show that the proposed method is effective in realtime detecting of instantaneous harmonic and reactive currents in single-phase circuits. When only detecting the total reactive currents, this method does not need a phase-locked loop circuit, and it also can be used in some special applications to provide different compensations on the ground of different requirements of electric network. Compared with the other methods based on the theory of instantaneous reactive power, this method is simple and easy to realize. 展开更多
关键词 Active filter HARMONIC Reactive current real-time detection Single-phase circuit Electric-network
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Changes in the Brain’s Intrinsic Organization in the Resting State with Real-Time fMRI Neurofeedback Training of Posterior Cingulate Cortex Activity
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作者 Yubao Wang Jipeng Zhang +2 位作者 Gaoyan Zhang Li Yao Zhiying Long 《Journal of Behavioral and Brain Science》 2017年第13期655-673,共19页
Real-time functional magnetic resonance imaging (rtfMRI) technology has been widely used to train subjects to actively regulate the activity of specific brain regions. Although many previous studies have demonstrated ... Real-time functional magnetic resonance imaging (rtfMRI) technology has been widely used to train subjects to actively regulate the activity of specific brain regions. Although many previous studies have demonstrated that neurofeedback training alters the functional connectivity between brain regions in the task state and resting state, it is unclear how the regulation of the key hub of the default mode network (DMN) affects the topological properties of the resting-state brain network. The current study aimed to investigate what topological changes would occur in the large-scale intrinsic organization of the resting state after the real-time down-regulation of the posterior cingulate cortex (PCC). The results indicated that the down-regulation of the PCC in the DMN reduced the functional connectivity of the PCC with the nodes outside of the DMN and reduced functional connectivity between the superior medial frontal gyrus (SFGmed) and parahippocampal gyrus (PHG) in the experimental group. Moreover, the nodal graph properties of the SFGmed were reduced, while that of the PHG showed the opposite alteration after the down-regulation of the PCC. These findings possibly suggest that the regulation of the key hub of the DMN, the PCC, mainly changed the information transfer of the SFGmed and PHG. 展开更多
关键词 real-time fMRI NEUROFEEDBACK DEFAULT Mode network POSTERIOR CINGULATE CORTEX Graph Theory
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A Real-Time-Enabled, Blackboard-Based, Publish/Subscribe Architecture for Wireless Sensor Nodes
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作者 Bjorn Stelte 《Wireless Sensor Network》 2010年第8期612-628,共17页
Wireless sensor network nodes have only limited resources concerning memory and battery life-time. Mem- ory can be efficiently used by sharing data, and the life-time of a battery can be extended, when the node has lo... Wireless sensor network nodes have only limited resources concerning memory and battery life-time. Mem- ory can be efficiently used by sharing data, and the life-time of a battery can be extended, when the node has long power saving sleep-phases. We propose a publish/subscribe architecture that achieves these two aims. The results of our work are of great interest for sensor application developers, giving them now the opportu- nity to use our architecture for sharing data among different applications on the node as well as the different layers of the operating system. We introduce a blackboard which is used for centrally storing published val- ues, like measured data from a monitored sensor. This makes it possible to share stored data without monitoring the sensors once again, which is advantageously concerning power consumption, memory space, and reaction time. Beside the proposed publish/subscribe method for sensor nodes with its notification possibili- ties, our architecture fulfills also real-time requirements. We show how the well-known sensor operating system MANTIS OS can be extended by a real-time enabled, blackboard-based publish/subscribe architect- ture. This architecture and first of all its implementation is of special interest for cross layer optimization of sensor applications. Cross-layer approaches benefit from our architecture because the available implementa- tion can be used as an efficient framework for central storing and managing of shared values. 展开更多
关键词 BLACKBOARD real-time PUBLISH/SUBSCRIBE ARCHITECTURE WIRELESS SENSOR network
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RTEX A REAL TIME EXECUTIVE FOR DCCS
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作者 荣广颐 于娅 《Journal of Donghua University(English Edition)》 EI CAS 1989年第Z1期72-85,共14页
This paper presents the design idea and implementation of a real time multiprocess executivededicated to a distributed computer control system(abbreviated as DCCS),RTEX.The hostprecessor is an INTEL 8344 microcontroll... This paper presents the design idea and implementation of a real time multiprocess executivededicated to a distributed computer control system(abbreviated as DCCS),RTEX.The hostprecessor is an INTEL 8344 microcontroller proper for mini size industrial control work station.A real time executive is designed to provide a friendly environment for users to develop their ownapplied software.In consideration of reliability and ease of maintenance the executive is imple-mented by a hierarchical structure with eight layers which include user applied programs,net-work communication,real time clock manager,interprocess communication,processcoordination,process manager,memory manager,hardware.For practical purpose the networkcommunication software is implemented by four layers,namely physical,datalink,transport andapplication.The bottom two layers are designed according to the Bit Bus protocol,so that thework station is compatible with the INTEL distributed system.Three parts,the kernel,networkcommunication and facilities for system initialization and applied software development are in-cluded. 展开更多
关键词 distributed control computer-computer COMMUNICATION real-time system processes hierarchical structure KERNEL network COMMUNICATION MICROPROCESSOR PL/M-51
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Patient Centered Real-Time Mobile Health Monitoring System
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作者 Won-Jae Yi Jafar Saniie 《E-Health Telecommunication Systems and Networks》 2016年第4期75-94,共20页
In this paper, we introduce a system architecture for a patient centered mobile health monitoring (PCMHM) system that deploys different sensors to determine patients’ activities, medical conditions, and the cause of ... In this paper, we introduce a system architecture for a patient centered mobile health monitoring (PCMHM) system that deploys different sensors to determine patients’ activities, medical conditions, and the cause of an emergency event. This system combines and analyzes sensor data to produce the patients’ detailed health information in real-time. A central computational node with data analyzing capability is used for sensor data integration and analysis. In addition to medical sensors, surrounding environmental sensors are also utilized to enhance the interpretation of the data and to improve medical diagnosis. The PCMHM system has the ability to provide on-demand health information of patients via the Internet, track real-time daily activities and patients’ health condition. This system also includes the capability for assessing patients’ posture and fall detection. 展开更多
关键词 Patient Remote Health Monitoring real-time Sensor Data Processing Wireless Body Sensor network Fall Detection Heart Monitoring
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Method for integer ambiguity resolution in GPS network RTK 被引量:5
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作者 潘树国 王庆 +1 位作者 柯福阳 邓健 《Journal of Southeast University(English Edition)》 EI CAS 2009年第4期491-495,共5页
A method for integer ambiguity resolution in the global positioning system (GPS) multi-reference station network real time kinematic (RTK) is proposed. First, the barycenter of the triangle of reference stations f... A method for integer ambiguity resolution in the global positioning system (GPS) multi-reference station network real time kinematic (RTK) is proposed. First, the barycenter of the triangle of reference stations for ambiguity resolution is taken as a reference point. The satellite which has the largest elevation angle with the reference point is selected as a reference satellite. The parameters for constructing the weight matrix of carrier phase observation and the criteria for checking the correctness of integer ambiguity resolution of a network are obtained. Then, the wide ambiguity is calculated by a linear combination method of dualband observation. And the LI ambiguity is obtained by a nonionosphere combination method. The Kalman filter is introduced to refine the floating-point solution of ambiguity and estimate the real-time tropospheric delay. Finally, the cofactor matrix of ambiguity is de-correlated by Z-transformation to reduce the searching space of the integer ambiguity solution and improve the efficiency of the least-squares ambiguity decorrelation adjustment (LAMBDA) algorithm. The experimental results show that this method can reliably obtain the integer ambiguity solution among multi-reference stations with 40 epochs. 展开更多
关键词 network real time kinematic AMBIGUITY troposphere: reference satellite least-squares ambiguity decorrelation adjustment
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基于TrueTime工具箱的网络控制系统及其在电机控制上的应用 被引量:6
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作者 程启明 郭瑞青 +1 位作者 杜许峰 夏征 《上海电力学院学报》 CAS 2009年第1期23-27,38,共6页
在引出了网络控制系统概念的基础上,分析了网络控制系统的特性及存在的问题,介绍了NCS的仿真工具箱TrueTime的组成、功能.以直流电机为对象,建立了一个基于TrueTime的NCS仿真模型,并进行了控制仿真分析.
关键词 网络控制系统 TRUEtime工具箱 网络时延 网络调度 实时控制 直流电机
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