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Utilising continuous glucose monitoring for glycemic control in diabetic kidney disease
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作者 Vamsidhar Veeranki Narayan Prasad 《World Journal of Diabetes》 SCIE 2024年第10期2006-2009,共4页
In this editorial,we comment on the article by Zhang et al.Chronic kidney disease(CKD)presents a significant challenge in managing glycemic control,especially in diabetic patients with diabetic kidney disease undergoi... In this editorial,we comment on the article by Zhang et al.Chronic kidney disease(CKD)presents a significant challenge in managing glycemic control,especially in diabetic patients with diabetic kidney disease undergoing dialysis or kidney transplantation.Conventional markers like glycated haemoglobin(HbA1c)may not accurately reflect glycemic fluctuations in these populations due to factors such as anaemia and kidney dysfunction.This comprehensive review discusses the limitations of HbA1c and explores alternative methods,such as continuous glucose monitoring(CGM)in CKD patients.CGM emerges as a promising technology offering real-time or retrospective glucose concentration measure-ments and overcoming the limitations of HbA1c.Key studies demonstrate the utility of CGM in different CKD settings,including hemodialysis and peritoneal dialysis patients,as well as kidney transplant recipients.Despite challenges like sensor accuracy fluctuation,CGM proves valuable in monitoring glycemic trends and mitigating the risk of hypo-and hyperglycemia,to which CKD patients are prone.The review also addresses the limitations of CGM in CKD patients,emphasizing the need for further research to optimize its utilization in clinical practice.Altogether,this review advocates for integrating CGM into managing glycemia in CKD patients,highlighting its superiority over traditional markers and urging clinicians to consider CGM a valuable tool in their armamentarium. 展开更多
关键词 Chronic kidney disease Diabetic kidney disease Glycemic control Continuous glucose monitoring Glycated hemoglobin Glycemic variability
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Determination of Monitoring Control Value for Concrete Gravity Dam Spatial Deformation Based on POT Model
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作者 Zhiwen Xie Tiantang Yu 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第6期2119-2135,共17页
Deformation can directly reflect the working behavior of the dam,so determining the deformation monitoring control value can effectively monitor the safety of dam operation.The traditional dam deformation monitoring c... Deformation can directly reflect the working behavior of the dam,so determining the deformation monitoring control value can effectively monitor the safety of dam operation.The traditional dam deformation monitoring control value only considers the single measuring point.In order to overcome the limitation,this paper presents a new method to determine the monitoring control value for concrete gravity dam based on the deformations of multi-measuring points.A dam’s comprehensive deformation displacement is determined by the measured values at different measuring points on the positive inverted vertical line and the corresponding weight of eachmeasuring point.The projection pursuit method(PPM)combined with the grey wolf optimization(GWO)algorithm is used to determine the weight of each measuring point according to the spatial correlation distribution characteristics of dam deformation.The peaks over threshold(POT)model based on the extreme value theory is adopted to determine the monitoring control value with the obtained dam comprehensive deformation displacement.In addition,the POTmodel is improved with the automatic threshold determinationmethod based on the 3σcriterion in probability theory and the GWO algorithm,which can avoid subjectivity and randomness in determining the threshold.The results of the engineering application show the feasibility and applicability of the proposed method. 展开更多
关键词 Concrete gravity dam DEFORMATION monitoring control value PPM GWO POT
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Mechanism,prevention,and control of mining-induced dynamic disasters in underground metal mines in China:Challenges and solutions
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作者 LI Peng CAI Mei-feng +3 位作者 MIAO Sheng-jun REN Fen-hua GORJIAN Mostafa PENG Chao 《Journal of Central South University》 SCIE EI CAS CSCD 2024年第8期2549-2606,共58页
Metal mineral resources play an indispensable role in the development of the national economy.Dynamic disasters in underground metal mines seriously threaten mining safety,which are major scientific and technological ... Metal mineral resources play an indispensable role in the development of the national economy.Dynamic disasters in underground metal mines seriously threaten mining safety,which are major scientific and technological problems to be solved urgently.In this article,the occurrence status and grand challenges of some typical dynamic disasters involving roof falling,spalling,collapse,large deformation,rockburst,surface subsidence,and water inrush in metal mines in China are systematically presented,the characteristics of mining-induced dynamic disasters are analyzed,the examples of dynamic disasters occurring in some metal mines in China are summarized,the occurrence mechanism,monitoring and early warning methods,and prevention and control techniques of these disasters are highlighted,and some new opinions,suggestions,and solutions are proposed simultaneously.Moreover,some shortcomings in current disaster research are pointed out,and the direction of efforts to improve the prevention and control level of dynamic disasters in China’s metal mines in the future is prospected.The integration of forward-looking key innovative theories and technologies in the abovementioned aspects will greatly enhance the cognitive level of disaster prevention and mitigation in China’s metal mining industry and achieve a significant shift from passive disaster relief to active disaster prevention. 展开更多
关键词 underground metal mines dynamic disasters MECHANISM monitoring and early warning prevention and control
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Sensitivity of Marine Controllable Source Electromagnetic Soundings for Identifying Plume Migration in Offshore CO_(2) Storage
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作者 Ning Qiu Chunwu Pan +3 位作者 Yongheng Zhang Bin Liu Zhen Sun Pengchun Li 《哈尔滨工程大学学报(英文版)》 CSCD 2024年第3期656-673,共18页
Offshore carbon dioxide(CO_(2)) storage is an effective method for reducing greenhouse gas emissions. However, when using traditional seismic wave methods to monitor the migration of sequestration CO_(2) plumes, the c... Offshore carbon dioxide(CO_(2)) storage is an effective method for reducing greenhouse gas emissions. However, when using traditional seismic wave methods to monitor the migration of sequestration CO_(2) plumes, the characteristics of wave velocity changes tend to become insignificant beyond a certain limit. In contrast, the controllable source electromagnetic method(CSEM) remains highly sensitive to resistivity changes. By simulating different CO_(2) plume migration conditions, we established the relevant models and calculated the corresponding electric field response characteristic curves, allowing us to analyze the CSEM's ability to monitor CO_(2) plumes. We considered potential scenarios for the migration and diffusion of offshore CO_(2) storage, including various burial depths, vertical extension diffusion, lateral extension diffusion,multiple combinations of lateral intervals, and electric field components. We also obtained differences in resistivity inversion imaging obtained by CSEM to evaluate its feasibility in monitoring and to analyze all the electric field(Ex, Ey, and Ez) response characteristics. CSEM has great potential in monitoring CO_(2) plume migration in offshore saltwater reservoirs due to its high sensitivity and accuracy. Furthermore, changes in electromagnetic field response reflect the transport status of CO_(2) plumes, providing an important basis for monitoring and evaluating CO_(2)transport behavior during storage processes. 展开更多
关键词 Offshore carbon dioxide storage Geophysics Resistivity inversion monitoring Plume migration Marine controllable source electromagnetic method
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Tool Condition Monitoring Based on Nonlinear Output Frequency Response Functions and Multivariate Control Chart
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作者 Yufei Gui Ziqiang Lang +1 位作者 Zepeng Liu Hatim Laalej 《Journal of Dynamics, Monitoring and Diagnostics》 2023年第4期243-251,共9页
Tool condition monitoring(TCM)is a key technology for intelligent manufacturing.The objective is to monitor the tool operation status and detect tool breakage so that the tool can be changed in time to avoid significa... Tool condition monitoring(TCM)is a key technology for intelligent manufacturing.The objective is to monitor the tool operation status and detect tool breakage so that the tool can be changed in time to avoid significant damage to workpieces and reduce manufacturing costs.Recently,an innovative TCM approach based on sensor data modelling and model frequency analysis has been proposed.Different from traditional signal feature-based monitoring,the data from sensors are utilized to build a dynamic process model.Then,the nonlinear output frequency response functions,a concept which extends the linear system frequency response function to the nonlinear case,over the frequency range of the tooth passing frequency of the machining process are extracted to reveal tool health conditions.In order to extend the novel sensor data modelling and model frequency analysis to unsupervised condition monitoring of cutting tools,in the present study,a multivariate control chart is proposed for TCM based on the frequency domain properties of machining processes derived from the innovative sensor data modelling and model frequency analysis.The feature dimension is reduced by principal component analysis first.Then the moving average strategy is exploited to generate monitoring variables and overcome the effects of noises.The milling experiments of titanium alloys are conducted to verify the effectiveness of the proposed approach in detecting excessive flank wear of solid carbide end mills.The results demonstrate the advantages of the new approach over conventional TCM techniques and its potential in industrial applications. 展开更多
关键词 intelligent manufacturing multivariate control chart Nonlinear Autoregressive with eXogenous Input modelling Nonlinear Output Frequency Response Functions tool condition monitoring
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Continuous glucose monitoring metrics in pregnancy with type 1 diabetes mellitus
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作者 Mohammad Sadiq Jeeyavudeen Mairi Crosby Joseph M Pappachan 《World Journal of Methodology》 2024年第1期6-17,共12页
Managing diabetes during pregnancy is challenging,given the significant risk it poses for both maternal and foetal health outcomes.While traditional methods involve capillary self-monitoring of blood glucose level mon... Managing diabetes during pregnancy is challenging,given the significant risk it poses for both maternal and foetal health outcomes.While traditional methods involve capillary self-monitoring of blood glucose level monitoring and periodic HbA1c tests,the advent of continuous glucose monitoring(CGM)systems has revolutionized the approach.These devices offer a safe and reliable means of tracking glucose levels in real-time,benefiting both women with diabetes during pregnancy and the healthcare providers.Moreover,CGM systems have shown a low rate of side effects and high feasibility when used in pregnancies complicated by diabetes,especially when paired with continuous subcutaneous insulin infusion pump as hybrid closed loop device.Such a combined approach has been demonstrated to improve overall blood sugar control,lessen the occurrence of preeclampsia and neonatal hypoglycaemia,and minimize the duration of neonatal intensive care unit stays.This paper aims to offer a comprehensive evaluation of CGM metrics specifically tailored for pregnancies impacted by type 1 diabetes mellitus. 展开更多
关键词 Type 1 diabetes mellitus Continuous glucose monitoring PREGNANCY Glycaemic control Continuous glucose monitoring system
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A HybridManufacturing ProcessMonitoringMethod Using Stacked Gated Recurrent Unit and Random Forest
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作者 Chao-Lung Yang Atinkut Atinafu Yilma +2 位作者 Bereket Haile Woldegiorgis Hendrik Tampubolon Hendri Sutrisno 《Intelligent Automation & Soft Computing》 2024年第2期233-254,共22页
This study proposed a new real-time manufacturing process monitoring method to monitor and detect process shifts in manufacturing operations.Since real-time production process monitoring is critical in today’s smart ... This study proposed a new real-time manufacturing process monitoring method to monitor and detect process shifts in manufacturing operations.Since real-time production process monitoring is critical in today’s smart manufacturing.The more robust the monitoring model,the more reliable a process is to be under control.In the past,many researchers have developed real-time monitoring methods to detect process shifts early.However,thesemethods have limitations in detecting process shifts as quickly as possible and handling various data volumes and varieties.In this paper,a robust monitoring model combining Gated Recurrent Unit(GRU)and Random Forest(RF)with Real-Time Contrast(RTC)called GRU-RF-RTC was proposed to detect process shifts rapidly.The effectiveness of the proposed GRU-RF-RTC model is first evaluated using multivariate normal and nonnormal distribution datasets.Then,to prove the applicability of the proposed model in a realmanufacturing setting,the model was evaluated using real-world normal and non-normal problems.The results demonstrate that the proposed GRU-RF-RTC outperforms other methods in detecting process shifts quickly with the lowest average out-of-control run length(ARL1)in all synthesis and real-world problems under normal and non-normal cases.The experiment results on real-world problems highlight the significance of the proposed GRU-RF-RTC model in modern manufacturing process monitoring applications.The result reveals that the proposed method improves the shift detection capability by 42.14%in normal and 43.64%in gamma distribution problems. 展开更多
关键词 Smart manufacturing process monitoring quality control gated recurrent unit neural network random forest
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A wireless solution for greenhouse monitoring and control system based on ZigBee technology 被引量:61
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作者 ZHANG Qian YANG Xiang-long +2 位作者 ZHOU Yi-ming WANG Li-ren GUO Xi-shan 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2007年第10期1584-1587,共4页
With the rapid development of wireless technologies, it is possible for Chinese greenhouses to be equipped with wireless sensor networks due to their low-cost, simplicity and mobility. In the current study, we compare... With the rapid development of wireless technologies, it is possible for Chinese greenhouses to be equipped with wireless sensor networks due to their low-cost, simplicity and mobility. In the current study, we compared the advantages of ZigBee with other two similar wireless networking protocols, Wi-Fi and Bluetooth, and proposed a wireless solution for green- house monitoring and control system based on ZigBee technology. As an explorative application of ZigBee technology in Chinese greenhouse, it may promote Chinese protected agriculture. 展开更多
关键词 GREENHOUSE monitoring and control WIRELESS ZIGBEE IEEE802.15.4 JN5121
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Underground ground control monitoring and interpretation,and numerical modeling, and shield capacity design 被引量:7
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作者 Syd S.Peng Jingyi Cheng +1 位作者 Feng Du Yuting Xue 《International Journal of Mining Science and Technology》 EI CSCD 2019年第1期79-85,共7页
Mine or longwall panel layout is a 3D structure with highly non-uniform stress distribution. Recognition of such fact will facilitate underground problem identification/investigation and solving by numerical modeling ... Mine or longwall panel layout is a 3D structure with highly non-uniform stress distribution. Recognition of such fact will facilitate underground problem identification/investigation and solving by numerical modeling through proper model construction. Due to its versatility, numerical modeling is the most popular method for ground control design and problem solving. However numerical modeling results require highly experienced professionals to interpret its validity/applicability to actual mining operations due to complicated mining and geological conditions. Underground ground control monitoring is routinely performed to predict roof behavior such as weighting and weighting interval without matching observation of face mining condition while the mining pressures are being monitored, resulting in unrealistic interpretation of the obtained data on mining pressure. The importance of ground control pressure monitoring and simultaneous observation of mining and geological conditions is illustrated by an example of shield leg pressure monitoring and interpretation in an U.S. longwall coal mine: it was found that the roof strata act like a plate, not an individual block of the size of a shield dimension, as commonly assumed by all researchers and shield capacity is not a fixed property for a longwall panel or a mine or a coal seam. A new mechanism on the interaction between shield's hydraulic leg pressure and roof strata for shield loading is proposed. 展开更多
关键词 MINE structure Ground control monitorING Numerical modeling SHIELD LEG pressure Periodic weighting
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Nonparametric Control Scheme for Monitoring Phase Ⅱ Nonlinear Profiles with Varied Argument Values 被引量:6
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作者 ZHANG Yang HE Zhen +1 位作者 FANG Juntao ZHANG Min 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2012年第3期587-597,共11页
Profile monitoring is used to check the stability of the quality of a product over time when the product quality is best represented by a function at each time point.However,most previous monitoring approaches have no... Profile monitoring is used to check the stability of the quality of a product over time when the product quality is best represented by a function at each time point.However,most previous monitoring approaches have not considered that the argument values may vary from profile to profile,which is common in practice.A novel nonparametric control scheme based on profile error is proposed for monitoring nonlinear profiles with varied argument values.The proposed scheme uses the metrics of profile error as the statistics to construct the control charts.More details about the design of this nonparametric scheme are also discussed.The monitoring performance of the combined control scheme is compared with that of alternative nonparametric methods via simulation.Simulation studies show that the combined scheme is effective in detecting parameter error and is sensitive to small shifts in the process.In addition,due to the properties of the charting statistics,the out-of-control signal can provide diagnostic information for the users.Finally,the implementation steps of the proposed monitoring scheme are given and applied for monitoring the blade manufacturing process.With the application in blade manufacturing of aircraft engines,the proposed nonparametric control scheme is effective,interpretable,and easy to apply. 展开更多
关键词 statistical process control profile monitoring nonparametric metric profile error
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Performance Monitoring and Diagnosis of Multivariable Model Predictive Control Using Statistical Analysis 被引量:11
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作者 张强 李少远 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2006年第2期207-215,共9页
A statistic-based benchmark was proposed for performance assessment and monitoring of model predic- tive control; the benchmark was straightforward and achievable by recording a set of output data only when the contro... A statistic-based benchmark was proposed for performance assessment and monitoring of model predic- tive control; the benchmark was straightforward and achievable by recording a set of output data only when the control performance was good according to the user’s selection. Principal component model was built and an auto- regressive moving average filter was identified to monitor the performance; an improved T2 statistic was selected as the performance monitor index. When performance changes were detected, diagnosis was done by model validation using recursive analysis and generalized likelihood ratio (GLR) method. This distinguished the fact that the per- formance change was due to plant model mismatch or due to disturbance term. Simulation was done about a heavy oil fractionator system and good results were obtained. The diagnosis result was helpful for the operator to improve the system performance. 展开更多
关键词 predictive control performance monitoring DIAGNOSIS principal component analysis
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Multivariate Statistical Process Monitoring and Control: Recent Developments and Applications to Chemical Industry 被引量:39
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作者 梁军 钱积新 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2003年第2期191-203,共13页
Multivariate statistical process monitoring and control (MSPM&C) methods for chemical process monitoring with statistical projection techniques such as principal component analysis (PCA) and partial least squares ... Multivariate statistical process monitoring and control (MSPM&C) methods for chemical process monitoring with statistical projection techniques such as principal component analysis (PCA) and partial least squares (PLS) are surveyed in this paper. The four-step procedure of performing MSPM&C for chemical process, modeling of processes, detecting abnormal events or faults, identifying the variable(s) responsible for the faults and diagnosing the source cause for the abnormal behavior, is analyzed. Several main research directions of MSPM&C reported in the literature are discussed, such as multi-way principal component analysis (MPCA) for batch process, statistical monitoring and control for nonlinear process, dynamic PCA and dynamic PLS, and on-line quality control by inferential models. Industrial applications of MSPM&C to several typical chemical processes, such as chemical reactor, distillation column, polymerization process, petroleum refinery units, are summarized. Finally, some concluding remarks and future considerations are made. 展开更多
关键词 multivariate statistical process monitoring and control (MSPM&C) fault detection and isolation (FDI) principal component analysis (PCA) partial least squares (PLS) quality control inferential model
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Improved Smith prediction monitoring AGC system based on feedback-assisted iterative learning control 被引量:4
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作者 张浩宇 孙杰 +2 位作者 张殿华 陈树宗 张欣 《Journal of Central South University》 SCIE EI CAS 2014年第9期3492-3497,共6页
The performance of Smith prediction monitoring automatic gauge control(AGC) system is influenced by model mismatching greatly in strip rolling process. Aiming at this problem, a feedback-assisted iterative learning co... The performance of Smith prediction monitoring automatic gauge control(AGC) system is influenced by model mismatching greatly in strip rolling process. Aiming at this problem, a feedback-assisted iterative learning control strategy, which learned unknown modeling error by using previous control information repeatedly, was introduced into Smith prediction monitoring AGC system. Firstly, conventional Smith predictor and improved Smith predictor with PI-P controller were analyzed. Secondly, on the basis of establishing of feedback-assisted iterative learning control strategy for improved Smith predictor, process control signal update law and control error were deduced, then convergence condition of this strategy was put forward and proved. Finally, after modeling the automatic position control system, the PI-P Smith prediction monitoring AGC system with feedback-assisted iterative learning control was researched through simulation. Simulation results indicate that this system remains stable during model mismatching. The robustness and response of monitoring AGC is improved by development of feedback-assisted iterative learning control strategy for PI-P Smith predictor. 展开更多
关键词 automatic gauge control Smith predictor monitoring automatic gauge control (AGC) feedback-assisted iterativelearning control automatic position control
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Research on Remote Monitoring and Fault Diagnosis Technology of Numerical Control Machine 被引量:1
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作者 ZHANG Jianyu~1 GAO Lixin~1 CUI Lingli~1 LI Xianghui~2 WANG Yingwang~2 1.Key Laboratory.of Advanced Manufacturing Technology,Beijing University of Technology,Beijing 100022,China 2.Tangshan Iron and Steel Corp.LTD,Tangshan 063000,China 《武汉理工大学学报》 CAS CSCD 北大核心 2006年第S2期748-752,共5页
Based on the internet technology,it has become possible to complete remote monitoring and fault diagnosis for the numerical control machine.In order to capture the micro-shock signal induced by the incipient fault on ... Based on the internet technology,it has become possible to complete remote monitoring and fault diagnosis for the numerical control machine.In order to capture the micro-shock signal induced by the incipient fault on the rotating parts,the reso- nance demodulation technology is utilized in the system.As a subsystem of the remote monitoring system,the embedded data acquisi- tion instrument not only integrates the demodulation board but also complete the collection and preprocess of monitoring data from different machines.Furthermore,through connecting to the internet,the data can be transferred to the remote diagnosis center and data reading and writing function can be finished in the database.At the same time,the problem of the IP address floating in the dial-up of web server is solved by the dynamic DNS technology.Finally,the remote diagnosis software developed on the Lab VIEW platform can analyze the monitoring data from manufacturing field.The research results have indicated that the equipment status can be monitored by the system effectively. 展开更多
关键词 NUMERICAL control MACHINE RESONANCE DEMODULATION REMOTE monitoring FAULT diagnosis
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A hierarchical architecture of centralized monitoring and controlling system and its high-performance and interoperability protocol 被引量:3
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作者 黄理灿 吴朝晖 潘云鹤 《Journal of Zhejiang University Science》 CSCD 2004年第1期22-30,共9页
This paper describes a hierarchical architecture and a high-performance and interoperability protocol for centralized monitoring and controlling systems (CMCS) . The protocol we proposed can interoperate different mon... This paper describes a hierarchical architecture and a high-performance and interoperability protocol for centralized monitoring and controlling systems (CMCS) . The protocol we proposed can interoperate different monitoring and controlling systems constructed by different companies, each with different functions and communication protocols. The protocol reduces the amount of traffic and has real-time and high-perfor-mance advantages. The protocol was implemented in CMCS for telecommunication power supply and air-condi-tioner used by the Telecommunication Bureau of Zhejiang Province. This paper deals with the hierarchical architecture and function of CMCS and packet format, command ID, and SDL description of its protocol. We also discuss the properties of the interoperability and performance of the protocol in this paper. 展开更多
关键词 monitoring and controlling system PROTOCOL ARCHITECTURE
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A Multi-Interface Remote Monitoring and Control System Architecture Based on Embedded Server 被引量:3
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作者 He Liu Lei Wang +1 位作者 Sheng-Peng Sun Ya-Dong Wang 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2013年第6期67-76,共10页
This paper presents a multi-interface embedded server architecture for remote real-time monitoring system and distributed monitoring applications. In the scheme,an embedded microprocessor( LPC3250 from NXP) is chosen ... This paper presents a multi-interface embedded server architecture for remote real-time monitoring system and distributed monitoring applications. In the scheme,an embedded microprocessor( LPC3250 from NXP) is chosen as the CPU of the embedded server with a linux operation system( OS) environment. The embedded server provides multiple interfaces for supporting various application scenarios. The whole network is based on local area network and adopts the Browser / Server( B / S) model. The monitoring and control node is as a browser endpoint and the remote node with an embedded server is as a server endpoint. Users can easily acquire various sensors information through writing Internet protocol address of remote node on the computer browser. Compared with client / server( C / S) mode,B / S model needs less maintain and can be applicable to large user group. In addition,a simple network management protocol( SNMP) is used for management of devices in Internet protocol( IP) networks. The results of the demonstration experiment show that the proposed system gives good support to manage the network from different user terminals and allows the users to better interact with the ambient environment. 展开更多
关键词 muhi-interface remote monitoring and control embedded server simple network management protocol (SNMP)CLC number:TP216+.1 Document code:AArticle ID:1005-9113(2013)06-0067-10
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Hellinger distance based probability distribution approach to performance monitoring of nonlinear control systems 被引量:2
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作者 李晨 黄彪 钱锋 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2015年第12期1945-1950,共6页
Control performance monitoring has attracted great attention in both academia and industry over the past two decades. However, most research efforts have been devoted to the performance monitoring of linear control sy... Control performance monitoring has attracted great attention in both academia and industry over the past two decades. However, most research efforts have been devoted to the performance monitoring of linear control systems, without considering the pervasive nonlinearities(e.g. valve stiction) present in most industrial control systems. In this work, a novel probability distribution distance based index is proposed to monitor the performance of non-linear control systems. The proposed method uses Hellinger distance to evaluate change of control system performance. Several simulation examples are given to illustrate the effectiveness of the proposed method. 展开更多
关键词 control performance monitoring Kernel density estimation Hellinger distance Nonlinear system
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Gas concentration monitoring system for small and medium-sized coal mines based on gas-sensing detection and single-chip control 被引量:1
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作者 Bin Guangfu Huang Zhenyu +1 位作者 Zhu Guanghui Li Xuejun 《Engineering Sciences》 EI 2010年第4期47-51,共5页
This paper is aimed at the actual conditions of disaster caused by gas in small and medium-sized coal mines. A new gas concentration monitoring system for coal mines is developed on the basis of gas-sensing detection ... This paper is aimed at the actual conditions of disaster caused by gas in small and medium-sized coal mines. A new gas concentration monitoring system for coal mines is developed on the basis of gas-sensing detection and single-chip control. The monitoring system uses the tin oxide as the main material of N-type semiconductor gas sensors, be- cause it has good sensitive characteristics for the flammable and explosive gas ( such as methane, carbon monoxide). The QM-N5-semiconductor gas sensor is adopted to detect the output values of the resistance under the different gas con- centrations. The system, designedly, takes the AT89C51 digital chip as the core of the circuit processing hardware structure to analyze and judge the input values of the resistance, and then achieve the control and alarm for going beyond the limit of gas concentration. The gas concentration monitoring system has man), advantages including simple in struc- ture, fast response time, stable performance and low cost. Thus, it can be widely used to monitor gas concentration and provide early wamings in small and medium-sized coal mines. 展开更多
关键词 gas concentration monitoring gas-sensing detection single-chip control small and medium-sized coal
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Microseismic monitoring and forecasting of dynamic disasters in underground hydropower projects in southwest China:A review 被引量:4
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作者 Biao Li Nuwen Xu +4 位作者 Peiwei Xiao Yong Xia Xiang Zhou Gongkai Gu Xingguo Yang 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2023年第8期2158-2177,共20页
The underground hydropower projects in Southwest China is characterized by large excavation sizes,high geostresses,complicated geological conditions and multiple construction processes.Various disasters such as collap... The underground hydropower projects in Southwest China is characterized by large excavation sizes,high geostresses,complicated geological conditions and multiple construction processes.Various disasters such as collapses,large deformations,rockbursts are frequently encountered,resulting in serious casualties and huge economic losses.This review mainly presents some representative results on microseismic(MS)monitoring and forecasting for disasters in hydropower underground engineering.First,a set of new denoising,spectral analysis,and location methods were developed for better identification and location of MS signals.Then,the tempo-spatial characteristics of MS events were analyzed to understand the relationship between field construction and damages of surrounding rocks.Combined with field construction,geological data,numerical simulation and parametric analysis of MS sources,the focal mechanism of MS events was revealed.A damage constitutive model considering MS fracturing size was put forward and feedback analysis considering the MS damage of underground surrounding rocks was conducted.Next,an MS multi-parameter based risk assessment and early warning method for dynamic disasters were proposed.The technology for control of the damage and deformation of underground surrounding rocks was proposed for underground caverns.Finally,two typical underground powerhouses were selected as case studies.These achievements can provide significant references for prevention and control of dynamic disasters for underground engineering with similar complicated geological conditions. 展开更多
关键词 MS monitoring Forecasting method control technology Dynamic disaster Underground engineering
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Oscillatory Failure Detection for Flight Control System Using Voting and Comparing Monitors
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作者 XUE Ying YAO Zhenqiang 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2019年第5期817-827,共11页
Oscillatory failure cases(OFC)detection in the fly-by-wire(FBW)flight control system for civil aircraft is addressed in this paper.First,OFC is ranked four levels:Handling quality,static load,global structure fatigue ... Oscillatory failure cases(OFC)detection in the fly-by-wire(FBW)flight control system for civil aircraft is addressed in this paper.First,OFC is ranked four levels:Handling quality,static load,global structure fatigue and local fatigue,according to their respect impact on aircraft.Second,we present voting and comparing monitors based on un-similarity redundancy commands to detect OFC.Third,the associated performances,the thresholds and the counters of the monitors are calculated by the high fidelity nonlinear aircraft models.Finally,the monitors of OFC are verified by the Iron Bird Platform with real parameters of the flight control system.The results show that our approach can detect OFC rapidly. 展开更多
关键词 OSCILLATORY failure FLY-BY-WIRE FLIGHT control system monitor VOTING
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