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ECG-I2S:a method for extracting heartbeat cycle and numerical signals from ECG captured images
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作者 Xiongjun ZHAO Linzhuang ZOU +1 位作者 Zhengyu LIU Shaoliang PENG 《Frontiers of Computer Science》 2025年第8期109-110,共2页
1 Introduction According to the World Health Organization,heart disease has been the leading cause of death worldwide for the past 20 years.Electrocardiography(ECG or EKG)records the electrophysiological activity of t... 1 Introduction According to the World Health Organization,heart disease has been the leading cause of death worldwide for the past 20 years.Electrocardiography(ECG or EKG)records the electrophysiological activity of the heart in time,allowing accurate diagnoses by clinicians[1].Despite the relative simplicity of ECG acquisition,its interpretation requires extensive training.Manual examination and re-examination of ECG paper records can be time-consuming,potentially delaying diagnosis.Machine learning,which uses algorithms to identify patterns within data and make predictive analyses,has played a significant role in interpreting ECGs[2]. 展开更多
关键词 machine learning time consuming interpretation diagnosis training electrophysiological activity heartbeat cycle ELECTROCARDIOGRAPHY
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基于Heartbeat+Nginx的高可用网站的设计与实现
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作者 江宏 《哈尔滨师范大学自然科学学报》 CAS 2024年第1期36-41,共6页
为了解决企业对于高可用网站的负载均衡问题,采用了Heartbeat作为高可用组件,对LVS(DR模式)负载均衡集群进行心跳监测,解决集群当中出现的单点故障问题.采用Nginx作为反向代理服务器对后端网站进行负载均衡,由LVS负载调度器来负载调度Ng... 为了解决企业对于高可用网站的负载均衡问题,采用了Heartbeat作为高可用组件,对LVS(DR模式)负载均衡集群进行心跳监测,解决集群当中出现的单点故障问题.采用Nginx作为反向代理服务器对后端网站进行负载均衡,由LVS负载调度器来负载调度Nginx集群进行线性扩展,进一步提高网站的负载能力,实现了网站的负载均衡与高可用.通过云客户端发生不同数量级连接访问请求,计算Heartbeat+Nginx负载均衡架构系统的访问数丢包率,验证系统的可行性.结果表明,Heartbeat+Nginx负载均衡架构在5000~8000个高并发访问时,丢包率为零,满足了用户对于Web服务器的高性能、高并发、高可靠性、高可用性等需求. 展开更多
关键词 集群 高可用 负载均衡 heartbeat NGINX
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Effect of heartbeat perception on heartbeat evoked potential waves 被引量:1
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作者 袁辉 颜红梅 +2 位作者 许小刚 韩飞 晏青 《Neuroscience Bulletin》 SCIE CAS CSCD 2007年第6期357-362,共6页
Objective Early researches found that different heartbeat perceivers have different heartbeat evoked potential (HEP)waves.Two tasks were considered in our experiments to get more details about the differences betwee... Objective Early researches found that different heartbeat perceivers have different heartbeat evoked potential (HEP)waves.Two tasks were considered in our experiments to get more details about the differences between good and poor heartbeat perceivers at attention and resting state.Methods Thirty channels of electroencephalogram(EEG)were recorded in 22 subjects,who had been subdivided into good and poor heartbeat perceivers by mental tracking task. Principal component analysis(PCA)was applied to remove cardiac field artifact(CFA)from the HEP.Results(1)The good heart-beat perceivers showed difference between attention and resting state in the windows from 250 ms to 450 ms after R wave at C3 location and from 100 ms to 300 ms after R wave at C4 location;(2)The difference waveforms between good and poor heartbeat perceivers was a positive waveform at FZ from 220 ms to 340 ms after R wave,which was more significant in attention state.Conclusion Attention state had more effect on the HEPs of good heartbeat perceivers than that of poor heartbeat perceivers;and perception ability influenced HEPs more strongly in the attention state than in the resting state. 展开更多
关键词 heartbeat perception heartbeat evoked potential cardiac field artifact principal component analysis
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利用Heartbeat实现Linux上的双机热备份系统 被引量:19
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作者 申志冰 罗宇 《计算机工程与应用》 CSCD 北大核心 2002年第19期126-128,共3页
该文简要介绍了Heartbeat双机热备份软件的原理、使用以及对其的改进,为在Linux平台上实现高可靠性系统提供了一个性价比很高的解决方案。
关键词 LINUX 双机热备份系统 操作系统 heartbeat程序
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Heartbeat-Gear:一种新型的实时心跳监测技术 被引量:11
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作者 谢长生 胡庆平 谭志虎 《计算机工程与科学》 CSCD 2004年第5期62-65,共4页
本文以双机热备高可用系统中心跳周期对高可用性能的影响为研究对象 ,提出了一种新型的实时心跳监测技术Heartbeat Gear。该技术通过动态排档式调整双机热备系统的心跳周期 ,能够在变化的请求服务环境下 ,提高系统的心跳周期环境适应能... 本文以双机热备高可用系统中心跳周期对高可用性能的影响为研究对象 ,提出了一种新型的实时心跳监测技术Heartbeat Gear。该技术通过动态排档式调整双机热备系统的心跳周期 ,能够在变化的请求服务环境下 ,提高系统的心跳周期环境适应能力 。 展开更多
关键词 双机热备高可用系统 heartbeat-Gear 实时心跳监测技术 心跳周期环境 计算机系统 高可用性能 心跳监测技术
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基于Heartbeat+MySQL的双机热备实现与改进 被引量:3
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作者 刘清华 杨桂芹 《自动化与仪器仪表》 2015年第1期159-160 163,163,共3页
针对中小型企业服务器高可用问题,本文提出和实现了纯软件双机热备的解决方案,并做了相应改进。在Ubuntu系统中安装Heartbeat、My SQL、Apache2三个开源软件,使其协同工作,充分发挥各软件的优势,最终在此基础上成功搭建高可用双机热备... 针对中小型企业服务器高可用问题,本文提出和实现了纯软件双机热备的解决方案,并做了相应改进。在Ubuntu系统中安装Heartbeat、My SQL、Apache2三个开源软件,使其协同工作,充分发挥各软件的优势,最终在此基础上成功搭建高可用双机热备服务器。通过编写服务器软件Apache2的监听脚本,使服务器的鲁棒性有了明显的提高。该双机热备解决方案采用纯软件方式实现,在很大程度上降低了中小型企业因购买昂贵设备带来的压力。 展开更多
关键词 双机热备 服务器 改进 heartbeat MY SQL
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Heartbeat与Drbd在大容量OLT中的应用 被引量:2
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作者 王鹤 孙晓艳 《现代电子技术》 2012年第24期131-133,137,共4页
针对大容量OLT系统高可用性能的要求,以Heartbeat与Drbd结合为研究对象,使系统具有热备高可用的同时又具有同步文件的功能。在此讨论了Heartbeat与Drbd结合应用的基本原理及可行性,实现了其应用于大容量OLT的热备系统中,改进了切换的速... 针对大容量OLT系统高可用性能的要求,以Heartbeat与Drbd结合为研究对象,使系统具有热备高可用的同时又具有同步文件的功能。在此讨论了Heartbeat与Drbd结合应用的基本原理及可行性,实现了其应用于大容量OLT的热备系统中,改进了切换的速度,增加其稳定性。实际测试表明Heartbeat与Drbd能很好地应用于大容理OLT中,系统快速稳定,满足应用系统高可用性。并基于开源Linux-HA项目下的免费软件使得降低成本,使其拥有更高的市场竞争力。 展开更多
关键词 Linux-HA heartbeat 大容量OLT DRBD
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Observer-Based Nonlinear Feedback Controls for Heartbeat ECG Tracking Systems 被引量:1
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作者 Witt Thanom Robert N. K. Loh 《Intelligent Control and Automation》 2012年第3期251-261,共11页
The analysis and design of observed-based nonlinear control of a heartbeat tracking system is investigated in this paper. Two of Zeeman’s heartbeat models are investigated and modified by adding the control input as ... The analysis and design of observed-based nonlinear control of a heartbeat tracking system is investigated in this paper. Two of Zeeman’s heartbeat models are investigated and modified by adding the control input as a pacemaker, thereby creating the control-affine nonlinear system models that capture the general heartbeat behavior of the human heart. The control objective is to force the output of the heartbeat models to track and generate a synthetic electrocardiogram (ECG) signal based on the actual patient reference data, obtained from the William Beaumont Hospitals, Michigan, and the PhysioNet database. The formulations of the proposed heartbeat tracking control systems consist of two phases: analysis and synthesis. In the analysis phase, nonlinear controls based on input-output feedback linearization are considered. This approach simplifies the difficult task of developing nonlinear controls. In the synthesis phase, observer-based controls are employed, where the unmeasured state variables are estimated for practical implementations. These observer-based nonlinear feedback control schemes may be used as a control strategy in electronic pacemakers. In addition, they could be used in a software-based approach to generate a synthetic ECG signal to assess the effectiveness of diagnostic ECG signal processing devices. 展开更多
关键词 heartbeat Model Electrocardiogram NONLINEAR CONTROL of Biological SYSTEMS Input-Output Feedback Linearization Observer-Based NONLINEAR CONTROL SYSTEMS
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Trusted Heartbeat Framework for Cloud Computing 被引量:1
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作者 Dipen Contractor Dhiren Patel Shreya Patel 《Journal of Information Security》 2016年第3期103-111,共9页
In cloud computing environment, as the infrastructure not owned by users, it is desirable that its security and integrity must be protected and verified time to time. In Hadoop based scalable computing setup, malfunct... In cloud computing environment, as the infrastructure not owned by users, it is desirable that its security and integrity must be protected and verified time to time. In Hadoop based scalable computing setup, malfunctioning nodes generate wrong output during the run time. To detect such nodes, we create collaborative network between worker node (i.e. data node of Hadoop) and Master node (i.e. name node of Hadoop) with the help of trusted heartbeat framework (THF). We propose procedures to register node and to alter status of node based on reputation provided by other co-worker nodes. 展开更多
关键词 Trusted heartbeat Cloud Computing Hadoop Framework REPUTATION Attestation
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Linux系统中利用Watchdog模块提升Heartbeat的高可用性研究
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作者 宋来 《电脑知识与技术》 2010年第4X期3163-3165,共3页
Linux内核从1.3.51版本开使提供硬件、软件Watchdog驱动。该文介绍了Linux内核对硬件、软件Watchdog的支持,然后研究了如何在Heartbeat中利用Watchdog机能进一步提升其高可用性,防止"脑裂"的发生。
关键词 LINUX Watchdog计时器 heartbeat 高可用性
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Non-invasive foetal heartbeat rate extraction from an underdetermined single signal
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作者 Ranjan Acharyya Neil L Scott Paul D Teal 《Health》 2009年第2期111-116,共6页
Extraction of foetal heartbeat rate from a single passive sound sensor on the mother’s abdomen is demonstrated. The extraction is based on the assumption that a disjoint band of frequencies exist and foetal signal is... Extraction of foetal heartbeat rate from a single passive sound sensor on the mother’s abdomen is demonstrated. The extraction is based on the assumption that a disjoint band of frequencies exist and foetal signal is concentrated in this band, and further that it can be represented conveniently as a set of wavelet coefficients. The algorithm has been applied to each stream of data obtained from six different channels and the detection performance is elaborated. The algorithm has also been tested on signals from non-pregnant abdomens to show successful rejection of adult heartbeat. The extraction of the desired signal is done in two stages so as to eliminate components from the maternal heart-beat. 展开更多
关键词 UNDERDETERMINED System FOETAL heartbeat RATE Wavelet BLIND Source Separation NON-INVASIVE Passive.
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Swarming Computational Approach for the Heartbeat Van Der Pol Nonlinear System
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作者 Muhammad Umar Fazli Amin +4 位作者 Soheil Salahshour Thongchai Botmart Wajaree Weera Prem Junswang Zulqurnain Sabir 《Computers, Materials & Continua》 SCIE EI 2022年第9期6185-6202,共18页
The present study is related to design a stochastic framework for the numerical treatment of the Van der Pol heartbeat model(VP-HBM)using the feedforward artificial neural networks(ANNs)under the optimization of parti... The present study is related to design a stochastic framework for the numerical treatment of the Van der Pol heartbeat model(VP-HBM)using the feedforward artificial neural networks(ANNs)under the optimization of particle swarm optimization(PSO)hybridized with the active-set algorithm(ASA),i.e.,ANNs-PSO-ASA.The global search PSO scheme and local refinement of ASA are used as an optimization procedure in this study.An error-based merit function is defined using the differential VP-HBM form as well as the initial conditions.The optimization of the merit function is accomplished using the hybrid computing performances of PSO-ASA.The designed performance of ANNs-PSO-ASA is implemented for the numerical treatment of the VP-HBM dynamics by fluctuating the pulse shape adjustment terms,external forcing factor and damping coefficient with fixed ventricular contraction period.To perform the correctness of the present scheme,the obtained numerical results through the designed ANN-PSO-ASA will be compared with the Adams numerical method.The statistical investigations with larger dataset are provided using the“mean absolute deviation”,“Theil’s inequality coefficient”and“variance account for”operators to perform the applicability,reliability,and effectiveness of the designed ANNs-PSO-ASA scheme for solving the VP-HBM. 展开更多
关键词 Particle swarm optimization van der Pol heartbeat system statistical analysis artificial neural networks active-set algorithm numerical computing
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DPHM: A FAULT DETECTION PROTOCOL BASED ON HEARTBEAT OF MULTIPLE MASTER-NODES
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作者 Dong Jian Zuo Decheng Liu Hongwei Yang Xiaozong 《Journal of Electronics(China)》 2007年第4期544-549,共6页
In most of fault detection algorithms of distributed system, fault model is restricted to fault of process, and link failure is simply masked, or modeled by process failure. Both methods can soon use up system resourc... In most of fault detection algorithms of distributed system, fault model is restricted to fault of process, and link failure is simply masked, or modeled by process failure. Both methods can soon use up system resource and potentially reduce the availability of system. A fault Detection Protocol based on Heartbeat of multiple Master-nodes (DPHM) is proposed, which can immediately and accurately detect and locate faulty links by adopting voting and electing mechanism among master-nodes. Thus, DPHM can effectively improve availability of system. In addition, in contrast with other detection protocols, DPHM reduces greatly the detection cost due to the structure of master-nodes. 展开更多
关键词 Distributed Fault detection heartbeat VOTING
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Double Crossover Points in the DFA of Heartbeats in Patients with Sleep Apnea
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作者 Midori Ichimaru Yuhei Ichimaru +1 位作者 George B. Moody Kuniaki Otsuka 《International Journal of Clinical Medicine》 2012年第7期688-692,共5页
Cardiovascular and cerebrovascular events have been observed during night-time associated with periodic breathing including sleep apnea and Cheyne-Stokes respiration. Early detection and treatment is important to redu... Cardiovascular and cerebrovascular events have been observed during night-time associated with periodic breathing including sleep apnea and Cheyne-Stokes respiration. Early detection and treatment is important to reduce night-time events. We clarified the characteristics of the dynamic nature of heartbeats associated with periodic breathing by using detrended fluctuation analysis (DFA). We analyzed heartbeats in eight recordings from the MIT-BIH Polysomnographic database. We observed two crossover points and defined three scaling exponents, β1 (n ≤ 40 beats), β2 (50 ≤ n ≤ 200), and β3 (251 ≤ n ≤ 1584). Compared with β1 (1.21 ± 0.13) and β3 (0.92 ± 0.16), scaling exponent β2 (0.62 ± 0.16) showed the statistically lowest value (p 0.05). And there was a negative relationship between the scaling exponent β2 and apnea/hypopnea index (p 0.05). These results indicate that DFA analysis of heartbeats may be useful for the early detection of sleep associated breathing disorders including sleep apnea and its severity. 展开更多
关键词 SLEEP APNEA DFA (Detrended Fluctuation Analysis) Scaling EXPONENT CROSSOVER POINTS heartbeats
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Predicting heartbeat arrival time for failure detection over internet using auto-regressive exogenous model
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作者 赵海军 《High Technology Letters》 EI CAS 2008年第4期370-376,共7页
Predicting heartbeat message arrival time is crucial for the quality of failure detection service over intemet. However, intemet dynamic characteristics make it very difficult to understand message behavior and accura... Predicting heartbeat message arrival time is crucial for the quality of failure detection service over intemet. However, intemet dynamic characteristics make it very difficult to understand message behavior and accurately predict heartbeat arrival time. To solve this problem, a novel black-box model is proposed to predict the next heartbeat arrival time. Heartbeat arrival time is modeled as auto-regressive process, heartbeat sending time is modeled as exogenous variable, the model' s coefficients are estimated based on the sliding window of observations and this result is used to predict the next heartbeat arrival time. Simulation shows that this adaptive auto-regressive exogenous (ARX) model can accurately capture heartbeat arrival dynamics and minimize prediction error in different network environments. 展开更多
关键词 INTERACT failure detection ADAPTIVE heartbeat PREDICTION
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Heartbeat and Respiration Rate Prediction Using Combined Photoplethysmography and Ballisto Cardiography
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作者 Valarmathi Ramasamy Dhandapani Samiappan RRamesh 《Intelligent Automation & Soft Computing》 SCIE 2023年第5期1365-1380,共16页
Owing to the recent trends in remote health monitoring,real-time appli-cations for measuring Heartbeat Rate and Respiration Rate(HARR)from video signals are growing rapidly.Photo Plethysmo Graphy(PPG)is a method that ... Owing to the recent trends in remote health monitoring,real-time appli-cations for measuring Heartbeat Rate and Respiration Rate(HARR)from video signals are growing rapidly.Photo Plethysmo Graphy(PPG)is a method that is operated by estimating the infinitesimal change in color of the human face,rigid motion of facial skin and head parts,etc.Ballisto Cardiography(BCG)is a non-surgical tool for obtaining a graphical depiction of the human body’s heartbeat by inducing repetitive movements found in the heart pulses.The resilience against motion artifacts induced by luminancefluctuation and the patient’s mobility var-iation is the major difficulty faced while processing the real-time video signals.In this research,a video-based HARR measuring framework is proposed based on combined PPG and BCG.Here,the noise from the input video signals is removed by using an Adaptive Kalmanfilter(AKF).Three different algorithms are used for estimating the HARR from the noise-free input signals.Initially,the noise-free sig-nals are subjected to Modified Adaptive Fourier Decomposition(MAFD)and then to Enhanced Hilbert vibration Decomposition(EHVD)andfinally to Improved Var-iation mode Decomposition(IVMD)for attaining three various results of HARR.The obtained values are compared with each other and found that the EHVD is showing better results when compared with all the other methods. 展开更多
关键词 heartbeat rate and respiration rate PHOTOPLETHYSMOGRAPHY BALLISTOCARDIOGRAPHY adaptive kalmanfilter
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The Research of Heartbeat Detection Technique for Blade Server
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作者 Weiwei Jiang Naikuo Chen Shihua Geng 《国际计算机前沿大会会议论文集》 2015年第1期120-121,共2页
The blade servers have been widely used in the telecommunications,financial and other big data processing fields as for the high efficiency, stability and autonomy. This study takes the hot redundancy design for dual-... The blade servers have been widely used in the telecommunications,financial and other big data processing fields as for the high efficiency, stability and autonomy. This study takes the hot redundancy design for dual-BMC management of blade servers as the research project, and puts forward a heartbeat detection program utilizing I2C for transmission of IPMI commands. And it’s successfully applied to the blade servers to achieve a hot redundancy, monitor and management of master/slave BMC management module, which is more standardized, reliable, and easy to implement. 展开更多
关键词 BMC BIG data BLADE SERVER heartbeat Detection IPMI
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ECG Heartbeat Classification Under Dataset Shift
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作者 Zhiqiang He 《Journal of Intelligent Medicine and Healthcare》 2022年第2期79-89,共11页
Electrocardiogram(ECG)is widely used to detect arrhythmia.Atrial fibrillation,atrioventricular block,premature beats,etc.can all be diagnosed by ECG.When the distribution of training data and test data is inconsistent... Electrocardiogram(ECG)is widely used to detect arrhythmia.Atrial fibrillation,atrioventricular block,premature beats,etc.can all be diagnosed by ECG.When the distribution of training data and test data is inconsistent,the accuracy of the model will be affected.This phenomenon is called dataset shift.In the real-world heartbeat classification system,the heartbeat of the training set and test set often comes from patients of different ages and genders,so there are differences in the distribution of data sets.The main challenge in applying machine learning algorithms to clinical AI systems is dataset shift.Test-time adaptation(TTA)aims to adapt a pre-trained model from the source domain(SD)to the target domain(TD)without using any SD data or TD labels,thereby reducing model performance degradation due to domain differences.We propose a method based on multimodal image fusion and continual test-time adaptation(FCTA)for accurate and efficient heartbeat classification.First,the original ECG data is converted into a three-channel color image through a multimodal image fusion framework.The impact of class imbalance on network performance is overcome using a batch weight loss function,and then the pretrained source model is adapted to the TD using a continual test-time adaptation(CTA)method.Although our method is very simple,compared with other domain adaptation methods,it can significantly improve model performance on the test set and reduce the impact caused by the difference in domain distribution. 展开更多
关键词 ECG heartbeat classification test-time adaptation dataset shift
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利用Heartbeat实现高可用集群系统 被引量:5
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作者 胡小勇 余翔湛 张宏莉 《微计算机信息》 2009年第1期259-261,共3页
该文介绍了高可用性集群系统的基本概念,讨论了开源Linux-HA项目下的Heartbeat的工作原理,提出了一种基于Linux的双机热备系统的方案。运行结果表明,该集群系统可以有效保证服务器业务的可靠运行。
关键词 集群 高可用 双机热备 心跳
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