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Development and Application of On-Line Corrosion Monitoring Device for Condenser Tube 被引量:1
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作者 曹杰玉 宋敬霞 +2 位作者 汪德良 龙国军 孙本达 《Electricity》 2004年第2期31-35,共5页
This paper introduces the development and industrial application of an on-line corrosion monitoring device for condenser tubes. Corrosion sensors are made up of representative condenser tubes chosen by eddy current te... This paper introduces the development and industrial application of an on-line corrosion monitoring device for condenser tubes. Corrosion sensors are made up of representative condenser tubes chosen by eddy current test, which enable the monitoring result to be consistent with the corrosion of actual condenser tubes. Localized corrosion rate of condenser tubes can be measured indirectly by a galvanic couple made up of tube segments with and without pits. Using this technology, corrosion problems can be found in time and accurately, and anticorrosive measures be made more economic and effective. Applications in two power plants showed the corrosion measurements are fast and accurate. 展开更多
关键词 condenser tube CORROSION on-line monitoring INSTRUMENTATION
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Quality of Service and Security on Cisco Network Devices, Coupled with the Development of a Mobile Application Prototype Software for Server Room Temperature Monitoring
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作者 Desire Mudenda Charles Smart Lubobya 《Journal of Computer and Communications》 2024年第8期123-140,共18页
In an era where digital technology is paramount, higher education institutions like the University of Zambia (UNZA) are employing advanced computer networks to enhance their operational capacity and offer cutting-edge... In an era where digital technology is paramount, higher education institutions like the University of Zambia (UNZA) are employing advanced computer networks to enhance their operational capacity and offer cutting-edge services to their academic fraternity. Spanning across the Great East Road campus, UNZA has established one of the most extensive computer networks in Zambia, serving a burgeoning community of over 20,000 active users through a Metropolitan Area Network (MAN). However, as the digital landscape continues to evolve, it is besieged with burgeoning challenges that threaten the very fabric of network integrity—cyber security threats and the imperatives of maintaining high Quality of Service (QoS). In an effort to mitigate these threats and ensure network efficiency, the development of a mobile application to monitor temperatures in the server room was imperative. According to L. Wei, X. Zeng, and T. Shen, the use of wireless sensory networks to monitor the temperature of train switchgear contact points represents a cost-effective solution. The system is based on wireless communication technology and is detailed in their paper, “A wireless solution for train switchgear contact temperature monitoring and alarming system based on wireless communication technology”, published in the International Journal of Communications, Network and System Sciences, vol. 8, no. 4, pp. 79-87, 2015 [1]. Therefore, in this study, a mobile application technology was explored for monitoring of temperatures in the server room in order to aid Cisco device performance. Additionally, this paper also explores the hardening of Cisco device security and QoS which are the cornerstones of this study. 展开更多
关键词 Quality of Service (QoS) Network Security Temperature monitoring Mobile Application Cisco devices
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A Fully‑Printed Wearable Bandage‑Based Electrochemical Sensor with pH Correction for Wound Infection Monitoring
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作者 Kanyawee Kaewpradub Kornautchaya Veenuttranon +2 位作者 Husanai Jantapaso Pimonsri Mittraparp‑arthorn Itthipon Jeerapan 《Nano-Micro Letters》 SCIE EI CAS 2025年第3期355-375,共21页
Wearable sensing systems have been designed to monitor health conditions in real-time by detecting analytes in human biofluids.Wound diagnosis remains challenging,necessitating suitable materials for high-performance ... Wearable sensing systems have been designed to monitor health conditions in real-time by detecting analytes in human biofluids.Wound diagnosis remains challenging,necessitating suitable materials for high-performance wearable sensors to offer prompt feedback.Existing devices have limitations in measuring pH and the concentration of pH-dependent electroactive species simultaneously,which is crucial for obtaining a comprehensive understanding of wound status and optimizing biosensors.Therefore,improving materials and analysis system accuracy is essential.This article introduces the first example of a flexible array capable of detecting pyocyanin,a bacterial virulence factor,while correcting dynamic pH fluctuations.We demonstrate that this combined sensor enhances accuracy by mitigating the impact of pH variability on pyocyanin sensor response.Customized screen-printable inks were developed to enhance analytical performance.The analytical performances of two sensitive sensor systems(i.e.,fully-printed porous graphene/multiwalled carbon nanotube(CNT)and polyaniline/CNT composites for pyocyanin and pH sensors)are evaluated.Partial least square regression is employed to analyze nonzero-order data arrays from square wave voltammetric and potentiometric measurements of pyocyanin and pH sensors to establish a predictive model for pyocyanin concentration in complex fluids.This sensitive and effective strategy shows potential for personalized applications due to its affordability,ease of use,and ability to adjust for dynamic pH changes. 展开更多
关键词 PYOCYANIN BANDAGES Wound monitoring Biosensor Wearable device
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On-Line Monitoring of Cutting Tool Fracture & Wear
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作者 王信义 肖定国 宋新民 《Journal of Beijing Institute of Technology》 EI CAS 1992年第2期139-150,共12页
A technique of detecting cutting tool fracture and ultimate wear by si- multaneously monitoring both the spindle motor current and cutting process related acoustic emission(AE)in the cutting process is reported.The te... A technique of detecting cutting tool fracture and ultimate wear by si- multaneously monitoring both the spindle motor current and cutting process related acoustic emission(AE)in the cutting process is reported.The technique can detect breakage of drills having diameter over 0.8mm,turning cutter crack of area over 0.2mm,and the ultimate wear.The principle,system construction,experimental method and result of the technique are discussed.The ratio of success in detection approaches 96% or higher. 展开更多
关键词 on-line monitoring acoustic emission/tool fracture motor current
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Device Monitoring Studio的设置与应用 被引量:1
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作者 李玉石 《计量与测试技术》 2016年第4期14-15,共2页
为了实现与PC连接外围硬件设备的通信监控和数据流记录,选用Device Monitoring Studio专业监控软件通过结构视图、原始数据视图、统计视图及串口配置信息视图等多个模块功能对硬件串口设备进行监控和数据分析。经过测试,软件所监控数据... 为了实现与PC连接外围硬件设备的通信监控和数据流记录,选用Device Monitoring Studio专业监控软件通过结构视图、原始数据视图、统计视图及串口配置信息视图等多个模块功能对硬件串口设备进行监控和数据分析。经过测试,软件所监控数据真实可靠,易于操作达到了预期的实验效果。将Device Monitoring Studio软件应用在工程数据监控中,可以极大的提高工作效率,给协议分析工作带来便利。 展开更多
关键词 device monitoring STUDIO 监控 串口 数据流 协议
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Self-adaptive PID controller of microwave drying rotary device tuning on-line by genetic algorithms 被引量:6
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作者 杨彪 梁贵安 +5 位作者 彭金辉 郭胜惠 李玮 张世敏 李英伟 白松 《Journal of Central South University》 SCIE EI CAS 2013年第10期2685-2692,共8页
The control design, based on self-adaptive PID with genetic algorithms(GA) tuning on-line was investigated, for the temperature control of industrial microwave drying rotary device with the multi-layer(IMDRDWM) and wi... The control design, based on self-adaptive PID with genetic algorithms(GA) tuning on-line was investigated, for the temperature control of industrial microwave drying rotary device with the multi-layer(IMDRDWM) and with multivariable nonlinear interaction of microwave and materials. The conventional PID control strategy incorporated with optimization GA was put forward to maintain the optimum drying temperature in order to keep the moisture content below 1%, whose adaptation ability included the cost function of optimization GA according to the output change. Simulations on five different industrial process models and practical temperature process control system for selenium-enriched slag drying intensively by using IMDRDWM were carried out systematically, indicating the reliability and effectiveness of control design. The parameters of proposed control design are all on-line implemented without iterative predictive calculations, and the closed-loop system stability is guaranteed, which makes the developed scheme simpler in its synthesis and application, providing the practical guidelines for the control implementation and the parameter design. 展开更多
关键词 industrial microwave DRYING ROTARY device SELF-ADAPTIVE PID controller genetic algorithm on-line tuning SELENIUM-ENRICHED SLAG
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On-line Monitoring for Phosphorus Removal Process and Bacterial Community in Sequencing Batch Reactor 被引量:4
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作者 崔有为 王淑莹 李晶 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2009年第3期484-492,共9页
For efficient energy consumption and control of effluent quality, the cycle duration for a sequencing batch reactor (SBR) needs to be adjusted by real-time control according to the characteristics and loading of waste... For efficient energy consumption and control of effluent quality, the cycle duration for a sequencing batch reactor (SBR) needs to be adjusted by real-time control according to the characteristics and loading of waste-water. In this study, an on-line information system for phosphorus removal processes was established. Based on the analysis for four systems with different ecological community structures and two operation modes, anaerobic-aerobic process and anaerobic-anaerobic process, the characteristic patterns of oxidation-reduction potential (ORP) and pH were related to phosphorous dynamics in the anaerobic, anoxic and aerobic phases, for determination of the end of phosphorous removal. In the operation mode of anaerobic-aerobic process, the pH profile in the anaerobic phase was used to estimate the relative amount of phosphorous accumulating organisms (PAOs) and glycogen accumulat-ing organisms (GAOs), which is beneficial to early detection of ecology community shifts. The on-line sensor val-ues of pH and ORP may be used as the parameters to adjust the duration for phosphorous removal and community shifts to cope with influent variations and maintain appropriate operation conditions. 展开更多
关键词 on-line monitoring phosphorus removal sequencing batch reactor PH oxidation-reduction potential
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A wearable real-time telemonitoring electrocardiogram device compared with traditional Holter monitoring 被引量:4
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作者 Qin Shen Jianqing Li +4 位作者 Chang Cui Xingyao Wang Hongxiang Gao Chengyu Liu Minglong Chen 《The Journal of Biomedical Research》 CAS CSCD 2021年第3期238-246,共9页
Arrhythmias are very common in the healthy populations as well as patients with cardiovascular diseases.Among them,atrial fibrillation(AF)and malignant ventricular arrhythmias are usually associated with some clinical... Arrhythmias are very common in the healthy populations as well as patients with cardiovascular diseases.Among them,atrial fibrillation(AF)and malignant ventricular arrhythmias are usually associated with some clinical events.Early diagnosis of arrhythmias,particularly AF and ventricular arrhythmias,is very important for the treatment and prognosis of patients.Holter is a gold standard commonly recommended for noninvasive detection of paroxysmal arrhythmia.However,it has some shortcomings such as fixed detection timings,delayed report and inability of remote real-time detection.To deal with such problems,we designed and applied a new wearable 72-hour triple-lead H3-electrocardiogram(ECG)device with a remote cloud-based ECG platform and an expertsupporting system.In this study,31 patients were recruited and 24-hour synchronous ECG data by H3-ECG and Holter were recorded.In the H3-ECG group,ECG signals were transmitted using remote real-time modes,and confirmed reports were made by doctors in the remote expert-supporting system,while the traditional modes and detection systems were used in the Holter group.The results showed no significant differences between the two groups in 24-hour total heart rate(HR),averaged HR,maximum HR,minimum HR,premature atrial complexes(PACs)and premature ventricular complexes(PVCs)(P>0.05).The sensitivity and specificity of capture and remote automatic cardiac events detection of PACs,PVCs,and AF by H3-ECG were 93%and 99%,98%and 99%,94%and 98%,respectively.Therefore,the long-term limb triple-lead H3-ECG device can be utilized for domiciliary ECG self-monitoring and remote management of patients with common arrhythmia under medical supervision. 展开更多
关键词 wearable ECG device HOLTER REAL-TIME remote ECG monitoring
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Massive Power Device Condition Monitoring Data Feature Extraction and Clustering Analysis using MapReduce and Graph Model 被引量:4
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作者 Hongtao Shen Peng Tao +1 位作者 Pei Zhao Hao Ma 《CES Transactions on Electrical Machines and Systems》 CSCD 2019年第2期221-230,共10页
Effective storage,processing and analyzing of power device condition monitoring data faces enormous challenges.A framework is proposed that can support both MapReduce and Graph for massive monitoring data analysis at ... Effective storage,processing and analyzing of power device condition monitoring data faces enormous challenges.A framework is proposed that can support both MapReduce and Graph for massive monitoring data analysis at the same time based on Aliyun DTplus platform.First,power device condition monitoring data storage based on MaxCompute table and parallel permutation entropy feature extraction based on MaxCompute MapReduce are designed and implemented on DTplus platform.Then,Graph based k-means algorithm is implemented and used for massive condition monitoring data clustering analysis.Finally,performance tests are performed to compare the execution time between serial program and parallel program.Performance is analyzed from CPU cores consumption,memory utilization and parallel granularity.Experimental results show that the designed framework and parallel algorithms can efficiently process massive power device condition monitoring data. 展开更多
关键词 Clustering analysis GRAPH feature extraction MAPREDUCE maxcompute power device condition monitoring.
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Research on Distribution of Electromagnetic Environment around Substations and Optimization Layout of On-line Monitoring 被引量:1
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作者 Li Peiming Xiao Jun Wang Wenjin 《Meteorological and Environmental Research》 CAS 2019年第6期60-63,共4页
The characteristics and distribution law of electromagnetic environment around substations with different levels of voltage were studied,and the main influencing factors were discussed. Meanwhile,a scheme for locating... The characteristics and distribution law of electromagnetic environment around substations with different levels of voltage were studied,and the main influencing factors were discussed. Meanwhile,a scheme for locating monitoring points suitable for an on-line monitoring system of electromagnetic environment was proposed. 展开更多
关键词 on-line monitoring ELECTROMAGNETIC environment SUBSTATION Optimization layout
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On-line monitoring of dissolved gas-in-oil with FTIR spectra 被引量:1
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作者 XianyongLiu YunluoLiu LiYue 《Journal of University of Science and Technology Beijing》 CSCD 2003年第4期65-68,共4页
To overcome the disadvantages of conventional DGA (dissolved gas-in-oil)analysis using gas chromatography and other electrochemical sensors, initial researches werecompleted to realize on-line monitoring of dissolved ... To overcome the disadvantages of conventional DGA (dissolved gas-in-oil)analysis using gas chromatography and other electrochemical sensors, initial researches werecompleted to realize on-line monitoring of dissolved gas-in-oil of power transformers using FTIR(Fourier Transform InfraRed) spectroscopy. Gas cell method is used to determine the characteristicabsorption peaks of each diagnostic gas; simple and novel devices and procedures were designed inorder to get measurable samples and spectra of mixed diagnostic gases with known concentration aretaken using long optical path gas cell. The range of wavelength is estimated to be 3.0-13.9 mum fromexperimental spectra data. Hence the corresponding sampling frequency range should be in 536-4288Hz and usable optical materials are suggested. It is concluded that a resolution of 10 cm^(-1) maywell satisfy the monitoring of all diagnostic gases and water content except hydrogen, and thelowest detection limit may be as low as 2Xl0^(-8) to acetylene with a 2.4-meter-long optical length. 展开更多
关键词 FTIR power transformer dissolved gas-in-oil on-line monitoring INFRAREDSPECTRA
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On-line Condition Monitoring and Diagnostic Network System for Rotating Machine Set 被引量:1
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作者 Li Fucai, He Zhengjia, Zi Yanyang School of Mechanical Engineering, Xi’an Jiaotong University, Xi’an 710049, P. R. China 《International Journal of Plant Engineering and Management》 2000年第4期136-141,共6页
Several industrial computers and a server are combined to set up the on-line monitoring and diagnostic system of turbo-generator sets. The main function of the system is to monitor machine sets' running condition.... Several industrial computers and a server are combined to set up the on-line monitoring and diagnostic system of turbo-generator sets. The main function of the system is to monitor machine sets' running condition. Through analyzing running data, technicians can detect whether there exist faults and where they occur. To share and transmit the dynamic information of the turbo-generator sets, a distributed network system is introduced. NetWare network operating system is used in the LAN (Local Area Network) system. The LAN is extended to realize the sharing of data and remote transmission of information. Furthermore, functions of monitoring and diagnostic clients are listed. 展开更多
关键词 rotating machine set on-line monitoring and diagnostic network system
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On-line monitoring of insulation quality of high voltage electric power equipment
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作者 SUN He-yi, ZHAO Xue-zeng, NIE Peng, BAI Jing-feng, YANG Yan-zhu (Harbin Institute of Technology, Harbin 150001, China) 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2000年第S1期77-80,共4页
Discusses on-line monitoring of electric parameters, such as dielectric loss, divulging current, equivalent capacitance and running voltage, and presents an on-line monitoring system of insulation quality, based on mo... Discusses on-line monitoring of electric parameters, such as dielectric loss, divulging current, equivalent capacitance and running voltage, and presents an on-line monitoring system of insulation quality, based on monitoring divulging current and dielectric loss of high voltage equipment, and its advantages, such as helping people to discover the hidden problems in a timely manner, to reduce power cut and overhaul and to improve security of power supply. 展开更多
关键词 INSULATION CAPABILITY HIGH-VOLTAGE EQUIPMENT on-line monitoring data PROCESSING
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Research Progress of On-line Monitoring Technology for Electromagnetic Environment of Power Transmission and Transformation Projects
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作者 Li Peiming Zhou Jian +2 位作者 Xiao Jun Wang Wenjin Ge Xiaoyang 《Meteorological and Environmental Research》 CAS 2019年第6期67-71,共5页
Based on the collection of relevant literature and cases,the research and application status of on-line monitoring technology for electromagnetic environment of power transmission and transformation projects at home a... Based on the collection of relevant literature and cases,the research and application status of on-line monitoring technology for electromagnetic environment of power transmission and transformation projects at home and abroad were introduced.Moreover,the problems existing in the on-line monitoring of electromagnetic environment were expounded,and the development prospect was forecasted. 展开更多
关键词 on-line monitoring TECHNOLOGY ELECTROMAGNETIC environment Power TRANSMISSION and TRANSFORMATION PROJECT
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An On-line Monitoring System for Partial Dischargefrom High Voltage Transformer
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作者 王哲 陈学允 蔡惟铮 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 1998年第2期52-56,共5页
An on-line monitoring system for partial discharge from high voltage transformer is presented with structure of hardware and principle of software discussed and a new effective method combining DFT with DWT is propose... An on-line monitoring system for partial discharge from high voltage transformer is presented with structure of hardware and principle of software discussed and a new effective method combining DFT with DWT is proposed to get rid of both sinusoidal continuous noise and other external discharges. 展开更多
关键词 Partial DISCHARGE on-line monitoring technique DISCRETE FOURIER TRANSFORM (DFT) DISCRETE WAVELET transform(DWT)
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ICT Devices: Vital Tools for Enhancing Road Traffic Monitoring
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作者 Emmanuel Nwabueze Ekwonwune Nwachukwu Catherine Ada Ngozi Osuagwu Oliver Eberechi 《Communications and Network》 2018年第3期43-50,共8页
Road Traffic monitoring involves the collection of data describing the characteristic of vehicles and their movement through road networks. Such data may be used for one of these purposes such as law enforcement, cong... Road Traffic monitoring involves the collection of data describing the characteristic of vehicles and their movement through road networks. Such data may be used for one of these purposes such as law enforcement, congestion and incident detection and increasing road capacity. Transportation is a requirement for every nation regardless of its economy, political stability, population size and technological development. Movement of goods and people from one place to another is crucial to maintain strong economic and political ties between the various components of any given nation among nations. However, there are different modes of transportation and the most paramount one to human beings is road transportation. Due to increase in the modes of transportation, road users encounter different problems such as road blockage and incidents. Therefore there is need to monitor users incidents and to know the causes. Road traffic monitoring can be done manually or using ICT devices. This paper focuses on how the use of ICT devices can enhance road traffic monitoring. It traces the brief history of transportation;it equally discussed road traffic and safety, tools for monitoring road traffic, Intelligent Transportation Systems (ITS) use for traffic monitoring and their benefits. The result shows that the use of ICT devices in road traffic monitoring should be a Millennium Goal for all developed and developing countries because of its numerous advantages in the reduction of the intensity of traffic and other road incidents. 展开更多
关键词 TRANSPORTATION Traffic monitoring deviceS Camera SURVEILLANCE
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Telemonitoring of Patients with Implantable Cardiac Devices to Manage Heart Failure: An Evaluation of Tablet-PC-Based Nursing Intervention Program
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作者 Aya Umeda Tomoko Inoue +1 位作者 Takuri Takahashi Hidetoshi Wakamatsu 《Open Journal of Nursing》 2014年第4期237-250,共14页
Background: With the rapid aging of society, the number of patients with heart failure has also increased. Implantable devices for heart failure have become standardized. Remote monitoring using cardiac devices has gr... Background: With the rapid aging of society, the number of patients with heart failure has also increased. Implantable devices for heart failure have become standardized. Remote monitoring using cardiac devices has grown in popularity for medical efficiency and the early detection of abnormalities. Our first aim was to develop a tablet-PC-based nursing intervention program for patients requiring remote monitoring of implantable cardiac devices. The second purpose was to evaluate the efficacy of the program by using mixed-methods research. Methods: The study consisted of two phases. In phase 1, we designed a tablet-PC-based nursing intervention program, on the basis of a literature review and qualitative data collected via semi-structured interviews. In phase 2, we conducted a randomized controlled trial that served as a preliminary investigation of the program. The outcome measures were readmission, unexpected visits to the clinic for heart problems, quality of life, self-care behavior, and self-efficacy. After the study, we interviewed each participant about his or her experiences with the program. Interviews were audio recorded, coded, and thematically analyzed. Results: The 33 patients with heart failure were randomized into two groups as follows: 17 patients in the telenursing group and 16 in the control group. During 6 months of follow-up, the readmission for heart failure occurred in 11% of the intervention group and 18% of the control group. There were no statistically significant differences between the groups at any outcome measures. Three themes were extracted via qualitative analysis: “getting a sense of safety,” “triggering a health behavior change,” and “feeling like a burden.” Conclusion: No improvements in rates of rehospitalization or unexpected clinic visits were seen in the quantitative study. However, signs of behavior modification were seen in the qualitative study. This program has the possibility of improving patient outcomes. 展开更多
关键词 Heart Failure TELEmonitoring TELENURSING Remote monitoring IMPLANTABLE Cardiac devices
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Modern Monitoring Intraocular Pressure Sensing Devices Based on Application Specific Integrated Circuits
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作者 Daniel Piso Patricia Veiga-Crespo Elena Vecino 《Journal of Biomaterials and Nanobiotechnology》 2012年第2期301-309,共9页
Glaucoma is a neurodegenerative condition that is the leading cause of irreversible blindness worldwide. Elevated intraocular pressure (IOP) is the main risk factor for the development and progression of the disease. ... Glaucoma is a neurodegenerative condition that is the leading cause of irreversible blindness worldwide. Elevated intraocular pressure (IOP) is the main risk factor for the development and progression of the disease. Methods to lower IOP remain the first line treatments for the condition. Current methods of IOP measurement do not permit temporary noninvasive monitoring 24-hour IOP on a periodic basis. Ongoing research will in time provide a means of developing a device that will enable continuous or temporary monitoring of IOP. At present a device suitable for clinical use is not yet available.This review contains a description of different devices currently in development for measuring IOP: soft contact lens, LC resonant circuits and on-chip sensing devices. All of them use application-specific integrated circuits (ASICS) to process the measured signals and send them to recording devices. Soft contact lens devices are based on an embedded strain gauge, LC circuits vary their resonance frequency depending on the intraocular pressure (IOP) and, finally, on-chip sensing devices include an integrated microelectromechanical sensor (MEMS). MEMS are capacitors whose capacity varies with IOP. These devices allow for an accurate IOP measurement (up to +/– 0.2 mm Hg) with high sampling rates (up to 1 sample/min) and storing 1 week of raw data. All of them operate in an autonomous way and even some of them are energetically independent. 展开更多
关键词 GLAUCOMA INTRAOCULAR Pressure monitoring IMPLANTABLE device Application-Specific Integrated CIRCUIT
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Analysis and Application of the Synthetic Relative Measuring Method in On-Line Monitoring for Capacitive Equipment in Power Systems
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作者 Qing Guo Li-Jun Qin Hua-Wei Jin 《Journal of Electronic Science and Technology》 CAS 2011年第3期270-277,共8页
On-line measurement for dielectric loss angle can effectively monitor the insulation condition of capacitive equipment in power systems. Synthetic relative measuring methods not only markedly overcome the shortcomings... On-line measurement for dielectric loss angle can effectively monitor the insulation condition of capacitive equipment in power systems. Synthetic relative measuring methods not only markedly overcome the shortcomings of traditional absolute measuring methods but also greatly improve the accuracy of dielectric loss angle measurement. However, synthetic relative measuring methods based on two or three pieces of capacitive equipment do not have the characteristic of generality. In this paper, a principle of synthetic relative measuring method is presented. The example of application for synthetic relative methods based on three and four pieces of capacitive equipment running in the same phase is taken to present the failure judgment matrices for N pieces of equipment. According to these matrices, the fault condition of N pieces of capacitive equipment can be watched, which is more general. Then some problems needing to be concerned along with two diagnostic methods used in diagnostic system are introduced. Finally, two programmable flow charts for the two methods are given and corresponding examples demonstrate their feasibility in practice. 展开更多
关键词 Index Terms-Capacitive equipment dielectric loss angle on-line monitoring synthetic relative measuring method failure judgment matrix.
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Insulation State On-line Monitoring and Running Management of Large Generator
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作者 Qiudong Sun Zhengxin Zhou Weiqin Guo 《Energy and Power Engineering》 2010年第3期203-207,共5页
This study presented an insulation state monitoring method for large generator based on radio frequency (RF) technique. As an on-line condition monitor and the precondition of condition-based maintenance (CBM), the RF... This study presented an insulation state monitoring method for large generator based on radio frequency (RF) technique. As an on-line condition monitor and the precondition of condition-based maintenance (CBM), the RF monitor used the high frequency current mutual inductor to detect the partial discharge signal from neutral wire of stator windings. According to the magnitude of indicative value of RF monitor, a five phase model was also proposed to manage the generator’s running better. The practices show that the proposed method is effective. 展开更多
关键词 Large GENERATOR PARTIAL DISCHARGE RADIO Frequency Technique on-line monitoring Running MANAGEMENT
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