A proof-of-concept indirect tire-pressure monitoring system is developed using artificial neural networks to identify the tire pressure of a vehicle tire.A quarter-car model was developed with MATLAB and Simulink to g...A proof-of-concept indirect tire-pressure monitoring system is developed using artificial neural networks to identify the tire pressure of a vehicle tire.A quarter-car model was developed with MATLAB and Simulink to generate simulated accelerometer output data.Simulation data are used to train and evaluate a recurrent neural network with long short-term memory blocks(RNN-LSTM)and a convolutional neural network(CNN)developed in Python with Tensorflow.Bayesian Optimization via SigOpt was used to optimize training and model parameters.The predictive accuracy and training speed of the two models with various parameters are compared.Finally,future work and improvements are discussed.展开更多
This paper presents the tire pressure monitoring system (TPMS) by using the system on chip (SoC) mixed signals with the help of Bluetooth transmission and in advantage of low power consumption design. This is to monit...This paper presents the tire pressure monitoring system (TPMS) by using the system on chip (SoC) mixed signals with the help of Bluetooth transmission and in advantage of low power consumption design. This is to monitor the variations in temperature and pressure of the vehicle’s tire, and the TPMS system is involved. It improves the driver’s safety by automatically detecting the tire pressure and temperature and then warning signal is sent to driver to take a measure, which prevents from accident. The proposed system of tire pressure monitoring system using SoC increases the speed of indication time to the driver by using mixed signals. The inflation of the tire can be avoided by preventing from high temperature and high pressure. Limitation of temperature and pressure in the previous system is also elongated i.e. temperature from 40℃ to 125℃ and pressure from 0 to 750 Kpa. Sensors, wireless communication (Bluetooth dongle) and SoC unit are used to design the low power TPMS. Quantitative results are taken and the analogy between temperature and pressure is also verified. The tested results proved by need of the practical system. Signal conditioning voltage and SoC unit is the trace for low power design TPMS. Finally, the performance of the system is tested and executed by using proteus software given as a real time application.展开更多
Tyre Pressure Monitoring Systems(TPMS)are installed in automobiles to monitor the pressure of the tyres.Tyre pressure is an important parameter for the comfort of the travelers and the safety of the passengers.Many me...Tyre Pressure Monitoring Systems(TPMS)are installed in automobiles to monitor the pressure of the tyres.Tyre pressure is an important parameter for the comfort of the travelers and the safety of the passengers.Many methods have been researched and reported for TPMS.Amongst them,vibration-based indirect TPMS using machine learning techniques are the recent ones.The literature reported the results for a perfectly balanced wheel.However,if there is a small unbalance,which is very common in automobile wheels,‘What will be the effect on the classification accuracy?’is the question on hand.This paper attempts to study the effect of unbalance of the wheel on the classification accuracy of an indirect TPMS system.The tyres filled with air are considered with different pressure values to represent puncture,normal,under pressure and overpressure conditions.The vibration signals of each condition were acquired and processed using machine learning techniques.The procedure is carried out with perfectly balanced wheels and known unbalanced wheels.The results are compared and presented.展开更多
The potential of monitoring the movement of typhoons using the precipitable water vapor(PWV) has been confirmed. However, monitoring the movement of typhoon is focused on PWV, making it difficult to describe the movem...The potential of monitoring the movement of typhoons using the precipitable water vapor(PWV) has been confirmed. However, monitoring the movement of typhoon is focused on PWV, making it difficult to describe the movement of a typhoon in detail minutely and resulting in insufficient accuracy. Hence,based on PWV and meteorological data, we propose an improved typhoon monitoring mode. First, the European Centre for Medium-Range Weather Forecasts Reanalysis 5-derived PWV(ERA5-PWV) and the Global Navigation Satellite System-derived PWV(GNSS-PWV) were compared with the reference radiosonde PWV(RS-PWV). Then, using the PWV and atmospheric parameters derived from ERA5, we discussed the anomalous variations of PWV, pressure(P), precipitation, and wind speed during different typhoons. Finally, we compiled a list of critical factors related to typhoon movement, PWV and P. We developed an improved multi-factor typhoon monitoring mode(IMTM) with different models(i.e.,IMTM-I and IMTM-II) in different cases with a higher density of GNSS observation or only Numerical Weather Prediction(NWP) data. The IMTM was evaluated through the reference movement speeds of HATO and Mangkhut from the China Meteorological Observatory Typhoon Network(CMOTN). The results show that the root mean square(RMS) of the IMTM-I is 1.26 km/h based on ERA5-P and ERA5-PWV,and the absolute bias values are mostly within 2 km/h. Compared with the models considering the single factor ERA5-P/ERA5-PWV, the RMS of the IMTM-I is improved by 26.3% and 38.5%, respectively. The IMTM-II model manifests a residual of only 0.35 km/h. Compared with the single-factor model based on GNSS-PWV/P, the residual of the IMTM-II model is reduced by 90.8% and 84.1%, respectively. These results propose that the typhoon movement monitoring approach combining PWV and P has evident advantages over the single-factor model and is expected to supplement traditional typhoon monitoring.展开更多
The phase change of CO_(2) has a significant bearing on the siting, injection, and monitoring of storage. The phase state of CO_(2) is closely related to pressure. In the process of seismic exploration, the informatio...The phase change of CO_(2) has a significant bearing on the siting, injection, and monitoring of storage. The phase state of CO_(2) is closely related to pressure. In the process of seismic exploration, the information of formation pressure can be response in the seismic data. Therefore, it is possible to monitor the formation pressure using time-lapse seismic method. Apart from formation pressure, the information of porosity and CO_(2) saturation can be reflected in the seismic data. Here, based on the actual situation of the work area, a rockphysical model is proposed to address the feasibility of time-lapse seismic monitoring during CO_(2) storage in the anisotropic formation. The model takes into account the formation pressure, variety minerals composition, fracture, fluid inhomogeneous distribution, and anisotropy caused by horizontal layering of rock layers(or oriented alignment of minerals). From the proposed rockphysical model and the well-logging, cores and geological data at the target layer, the variation of P-wave and S-wave velocity with formation pressure after CO_(2) injection is calculated. And so are the effects of porosity and CO_(2) saturation. Finally, from anisotropic exact reflection coefficient equation, the reflection coefficients under different formation pressures are calculated. It is proved that the reflection coefficient varies with pressure. Compared with CO_(2) saturation, the pressure has a greater effect on the reflection coefficient. Through the convolution model, the seismic record is calculated. The seismic record shows the difference with different formation pressure. At present, in the marine CO_(2) sequestration monitoring domain, there is no study involving the effect of formation pressure changes on seismic records in seafloor anisotropic formation. This study can provide a basis for the inversion of reservoir parameters in anisotropic seafloor CO_(2) reservoirs.展开更多
This paper presents an RF energy harvesting system for wireless intraocular pressure monitoring applications.The system consists of an implantable antenna and a rectifier.A new sizing strategy is adopted to optimize t...This paper presents an RF energy harvesting system for wireless intraocular pressure monitoring applications.The system consists of an implantable antenna and a rectifier.A new sizing strategy is adopted to optimize the conversion efficiency of the rectifier,and the design principle of an implantable antenna is introduced from material selection and structure design.Results from testing demonstrate that the antenna gain is about-20 dBi and the rectifier's maximum total conversion efficiency which contains match efficiency and rectifying efficiency is 47.18%under the implementation of0.18μm standard CMOS process.The maximum power obtained from the proposed system is 8μW when the power density of electromagnetic wave is lower than the national standard 40μW/cm^2 at915 MHz,which is enough to power the intraocular pressure monitoring system.展开更多
An epidural blood patch (EBP) is a procedure performed by injecting autologous blood into a patient’s epidural space, usually at the site of a suspected CSF leak. It is typically performed in patients with characteri...An epidural blood patch (EBP) is a procedure performed by injecting autologous blood into a patient’s epidural space, usually at the site of a suspected CSF leak. It is typically performed in patients with characteristic postural headaches due to low intracranial pressure. We report a case of a young female with an implanted Miethke Sensor Reservoir, which was used for continuous intracranial pressure (ICP) monitoring during a two-level epidural blood patch. ICP increased only with thoracic injection, suggesting thoracic EBP may have greater efficacy than lumbar EBP in treating SIH and PDPH when the site of CSF leak is unknown.展开更多
Flexible and wearable pressure sensors hold immense promise for health monitoring,covering disease detection and postoperative rehabilitation.Developing pressure sensors with high sensitivity,wide detection range,and ...Flexible and wearable pressure sensors hold immense promise for health monitoring,covering disease detection and postoperative rehabilitation.Developing pressure sensors with high sensitivity,wide detection range,and cost-effectiveness is paramount.By leveraging paper for its sustainability,biocompatibility,and inherent porous structure,herein,a solution-processed all-paper resistive pressure sensor is designed with outstanding performance.A ternary composite paste,comprising a compressible 3D carbon skeleton,conductive polymer poly(3,4-ethylene dioxythiophene):poly(styrenesulfonate),and cohesive carbon nanotubes,is blade-coated on paper and naturally dried to form the porous composite electrode with hierachical micro-and nano-structured surface.Combined with screen-printed Cu electrodes in submillimeter finger widths on rough paper,this creates a multiscale hierarchical contact interface between electrodes,significantly enhancing sensitivity(1014 kPa-1)and expanding the detection range(up to 300 kPa)of as-resulted all-paper pressure sensor with low detection limit and power consumption.Its versatility ranges from subtle wrist pulses,robust finger taps,to large-area spatial force detection,highlighting its intricate submillimetermicrometer-nanometer hierarchical interface and nanometer porosity in the composite electrode.Ultimately,this all-paper resistive pressure sensor,with its superior sensing capabilities,large-scale fabrication potential,and cost-effectiveness,paves the way for next-generation wearable electronics,ushering in an era of advanced,sustainable technological solutions.展开更多
Objective:To explore the effect of continuous non-invasive blood pressure monitoring on intraoperative hemodynamics and postoperative myocardial injury in craniotomy.Methods:120 cases of elective craniotomy were divid...Objective:To explore the effect of continuous non-invasive blood pressure monitoring on intraoperative hemodynamics and postoperative myocardial injury in craniotomy.Methods:120 cases of elective craniotomy were divided into the self-control group(continuous non-invasive blood pressure monitoring and intermittent cuff non-invasive blood pressure monitoring,CNAP group)and propensity score matching group(only intermittent cuff non-invasive blood pressure measurement in previous craniotomy,PSM group);Goal-directed hemodynamic management in CNAP group included heart rate(HR),blood pressure(BP),stroke volume(SV),stroke variability(SVV),and systemic vascular resistance index(SVRI).The main index is to compare the troponin level within 72 hours after operation between the CNAP group and the PSM group;The secondary indicators are the comparison of the hemodynamic conditions between the CNAP group and the PSM at 10 specific time points.Results:The incidence of postoperative myocardial injury in the CNAP group was significantly lower than that in the PSM group(12%vs.30%,P=0.01);in the CNAP group hypotensive episodes(6 vs.3,P=0.01),positive balance of fluid therapy(700 vs.500 mL,P<0.001),more use of vasoactive drugs(29 vs.18,P=0.04),more stable hemodynamics medical status(P=0.03)were recorded.Conclusion:The hemodynamic management strategy based on continuous non-invasive blood pressure monitoring can reduce the incidence of myocardial injury after elective craniotomy and maintain a more stable hemodynamic state.展开更多
Monitoring tire pressure of cars and signaling abnormal conditions is an important means to prevent deadly accidents. Large achievements have been gained, especially in direct tire pressure monitoring system(TPMS). ...Monitoring tire pressure of cars and signaling abnormal conditions is an important means to prevent deadly accidents. Large achievements have been gained, especially in direct tire pressure monitoring system(TPMS). But there has been rarely research on indirect TPMS in the world. In China, the research on indirect TPMS is almost lacking. The international research on the indirect monitoring tire pressure method is mainly based on measuring and comparing the rotating speed of wheels. But it is very difficult to measure wheel rotating speed accurately because of the influence of many random factors. In this paper, the authors propose a new method in which the tire pressure can be monitored indirectly. This method can be used for tire calibration, wheel speed frequency standardization, wheel speed frequency comparison, and abnormal tire pressure determination. The pulse frequencies from wheel speed sensors of ABS are used to indicate tire deformation. Because the frequency has a relationship with tire deformation, the tire deformation reflects the tire pressure. Small sample statistics is used in the new method to increase the accuracy, and the experimental samples using the principle of the new method have been made and tested. The result of vehicle tests on road demonstrates that the method is efficient and accurate to monitor tire pressure. The research has positive potential for developing products.展开更多
Fully mechanized solid backfill mining(FMSBM) technology adopts dense backfill body to support the roof. Based on the distinguishing characteristics and mine pressure control principle in this technology, the basic pr...Fully mechanized solid backfill mining(FMSBM) technology adopts dense backfill body to support the roof. Based on the distinguishing characteristics and mine pressure control principle in this technology, the basic principles and methods for mining pressure monitoring were analyzed and established. And the characteristics of overburden strata movement were analyzed by monitoring the support resistance of hydraulic support, the dynamic subsidence of immediate roof, the stress of backfill body, the front abutment pressure, and the mass ratio of cut coal to backfilled materials. On-site strata behavior measurements of 7403 W solid backfilling working face in Zhai Zhen Coal Mine show that the backfill body can effectively support the overburden load, obviously control the overburden strata movement, and weaken the strata behaviors distinctly. Specific performances are as follows. The support resistance decreases obviously; the dynamic subsidence of immediate roof keeps consistent to the variation of backfill body stress, and tends to be stable after the face retreating to 120-150 m away from the cut. The peak value of front abutment pressure arises at 5-12 m before the operating face, and mass ratio is greater than the designed value of 1.15, which effectively ensures the control of strata movement. The research results are bases for intensively studying basic theories of solid backfill mining strata behaviors and its control, and provide theoretical guidance for engineering design in FMSBM.展开更多
Background Fall injuries are common among the elderly. The aim of this study was to investigate whether blood-pressure patterns, as measured by 24-h ambulatory blood pressure monitoring (ABPM), or intensification of...Background Fall injuries are common among the elderly. The aim of this study was to investigate whether blood-pressure patterns, as measured by 24-h ambulatory blood pressure monitoring (ABPM), or intensification of antihypertensive therapy following the 24-h ABPM, may be associated with fall injuries in hypertensive elderly patients. Methods In a retrospective study, community-based elderly patients (age ≥ 70 years) who were referred to 24-h ABPM were evaluated for fall injuries within one-year post-ABPM. We compared the clinical characteristics, 24-h ABPM patterns and the intensification of hypertensive therapy following 24-h ABPM, between patients with and without a fall injury. Results Overall 1032 hypertensive elderly patients were evaluated. Fifty-five (5.3%) had a fall injury episode in the year following ABPM. Patients with a fall injury were significantly older, and with higher rates of previous falls. Lower 24-h diastolic blood-pressure (67.3 ± 7.6 vs. 70.7 ± 8.8 mmHg; P 〈 0.005) and increased pulse-pressure (74.7 ± 14.3 vs. 68.3 ± 13.7 mmHg; P 〈 0.005), were found in the patients with a fall injury, compared to those without a fall injury. After adjustment for age, gender, diabetes mellitus and previous falls, lower diastolic blood-pressure and increased pulse-pressure were independent predictors of fall injury. Intensification of antihypertensive treatment following the 24-h ABPM was not associated with an increased rate of fall injury. Conclusions Low diastolic blood-pressure and increased pulse-pressure in 24-h ABPM were associated with an increased risk of fall injury in elderly hypertensive patients. Intensification of antihypertensive treatment following 24-h ABPM was not associated with an increased risk of fall injury.展开更多
Despite an increasing popularity of home blood pressure monitoring (HBPM) over the last few decades, little is known about HBPM use among hypertensive patients in the rural areas. A cross-sectional survey including 31...Despite an increasing popularity of home blood pressure monitoring (HBPM) over the last few decades, little is known about HBPM use among hypertensive patients in the rural areas. A cross-sectional survey including 318 hypertensive patients was conducted in a rural community in Beijing, China, in 2012. Participants were mainly recruited from a community health clinic and completed the questionnaires assessing HBPM usage. Binary logistic regression models were used for the analysis of medication adherence with age, gender, level of education marital status, perceived health status, duration of hypertension, HBPM use, and frequency of performing BP measurement. Among the total population, 78 (24.5%) reported currently use of HBPM. Only 5.1% of the HBPM users cited doctor’s advice as the reason for using HBPM. Analysis of the risk factors of poor medication adherence by multivariable modeling indicated significant associations between the duration of hypertension (adjusted OR, 3.31;95% CI, 1.91-5.72;P 01), frequency of performing BP measurements (adjusted OR, 2.33;95% CI, 1.42-3.83;展开更多
BACKGROUND: Noninvasive monitoring of intra-abdominal pressure(IAP) by measuring abdominal wall tension(AWT) was effective and feasible in previous postmortem and animal studies. This study aimed to investigate the fe...BACKGROUND: Noninvasive monitoring of intra-abdominal pressure(IAP) by measuring abdominal wall tension(AWT) was effective and feasible in previous postmortem and animal studies. This study aimed to investigate the feasibility of the AWT method for noninvasively monitoring IAP in the intensive care unit(ICU).METHODS: In this prospective study, we observed patients with detained urethral catheters in the ICU of Shanghai Tenth People's Hospital between April 2011 and March 2013. The correlation between AWT and urinary bladder pressure(UBP) was analyzed by linear regression analysis. The effects of respiratory and body position on AWT were evaluated using the paired samples t test, whereas the effects of gender and body mass index(BMI) on baseline AWT(IAP<12 mm Hg) were assessed using one-way analysis of variance.RESULTS: A total of 51 patients were studied. A significant linear correlation was observed between AWT and UBP(R=0.986, P<0.01); the regression equation was Y=–1.369+9.57X(P<0.01). There were signif icant differences among the different respiratory phases and body positions(P<0.01). However, gender and BMI had no signif icant effects on baseline AWT(P=0.457 and 0.313, respectively).CONCLUSIONS: There was a signif icant linear correlation between AWT and UBP and respiratory phase, whereas body position had signif icant effects on AWT but gender and BMI did not. Therefore, AWT could serve as a simple, rapid, accurate, and important method to monitor IAP in critically ill patients.展开更多
This article is a review of 25 publications on ambulatory blood pressure monitoring(ABPM) and the importance of its results in everyday clinical practice. These studies, published in 2008-2011, were selected from the ...This article is a review of 25 publications on ambulatory blood pressure monitoring(ABPM) and the importance of its results in everyday clinical practice. These studies, published in 2008-2011, were selected from the Scopus database, but are also available in Pubmed. They were prepared by researchers from around the world, concerned with the problems of proper control of blood pressure(BP), and of abnormalities in the circadian pattern of BP in patients with arterial hypertension, diabetes mellitus or renal failure. In the first part of this article, I analyse publications focused on some nuances in the methodology of ABPM and recommend ways to avoid some traps, related not only to the individual patient but also to the device used and the technical staff. The next section is devoted to the advantages of ABPM as a diagnostic tool which enables clinicians to learn about patients' BP during sleep, and emphasizes the practical implications of this information for so-called chronotherapy. This section also presents some new studies on the prognostic value of ABPM in patients with cardiovascular(CV) risk. Some recent articles on the results of various methods of pharmacological treatment of arterial hypertension in different agegroups are then described. The observations presented in this article may be helpful not only for researchers interested in the chronobiology of the CV system, but also for general practitioners using ABPM.展开更多
Heart failure (HF) is an emerging epidemic associate with significant morbidity, mortality, and health care expenditure. Although there were major advances in pharmacologic and device based therapies for the managemen...Heart failure (HF) is an emerging epidemic associate with significant morbidity, mortality, and health care expenditure. Although there were major advances in pharmacologic and device based therapies for the management of HF, mortality of this condition remains high. Accurate monitoring of HF patients for exacerbations is very important to reduce recurrent hospitalizations and its associated complications. With the failure of clinical signs, tele-monitoring, and laboratory bio-markers to function as early markers of HF exacerbations, more sophisticated techniques were sought to accurately predict the circulatory status in HF patients in order to execute timely pharmacological intervention to reduce frequent hospitalizations. CardioMEMS<sup>TM</sup> (St. Jude Medical, Inc., Saint Paul, Minnesota) is an implantable, wireless pulmonary arterial pressure (PAP) monitoring system which transmits the patient’s continuous PAPs to the treating health care provider in the ambulatory setting. PAP-guided medical therapy modification has been shown to significantly reduce HF-related hospitalization and overall mortality. In advanced stages of HF, wireless access to hemodynamic information correlated with earlier left ventricular assist device implantation and shorter time to heart transplantation.展开更多
The wide pillars are generally popular due to the high productivity and efficiency in Northwest China.The distribution of lateral abutment pressure in coal pillars is important for mining safety.To reveal the effect o...The wide pillars are generally popular due to the high productivity and efficiency in Northwest China.The distribution of lateral abutment pressure in coal pillars is important for mining safety.To reveal the effect of the first mining on the lateral abutment pressure distribution and evolution in wide pillars,an in-situ experiment,theoretical analysis and numerical simulation were performed.First,the field monitoring of lateral abutment pressure was conducted from the perspective of time and space in the Chahasu Coal Mine,Huangling No.2 Coal Mine and Lingdong Coal Mine during the first mining.Based on the field monitoring stress,a theoretical model was proposed to reveal the lateral abutment pressure distribution.The methodology was demonstrated through a case study.Aiming at the distribution mechanism,a numerical experiment was conducted through the finite-discrete element method(FDEM).Last,field observations of borehole fractures were performed to further study the damage distribution.In addition,two types of lateral abutment pressure evolution with mining advance were discussed.Suggestions on the stress monitoring layout were proposed as well.The results could provide foundations for strata control and disaster prevention in wide pillars in underground coal mines.展开更多
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
Background HIRFL is a heavy ion accelerator built by the Institute of Modern Physics,Chinese Academy of Sciences,which constitutes a total length of over 900 m by the SFC,SSC,CSRm,CSRe and so on.It bears a lot of rese...Background HIRFL is a heavy ion accelerator built by the Institute of Modern Physics,Chinese Academy of Sciences,which constitutes a total length of over 900 m by the SFC,SSC,CSRm,CSRe and so on.It bears a lot of research task of the country,so to ensure its safe operation is very important.Purpose Cool-water system is a key part in HIRFL,and the parameters of the cool-water system need to be monitored before an accident occurs.Methods This article describes three aspects of the system,from the water leakage detection,pressure monitoring,to the water-level monitoring.A complete monitor system was designed and constructed,including the hardware structure;the data transfer mode,as well as specific control program.C++,FLASH and SCADA are used in the monitoring system.Results Fault alarm was performed timely and accurately by the monitoring system,and many accidents were avoided.Conclusion Water system monitoring is an important part of the accelerator control system.It will also play a major role in the construction of large-scale scientific device named HIAF in the further.展开更多
This article outlines the development of downhole monitoring and data transmission technology for separated zone water injection in China.According to the development stages,the principles,operation processes,adaptabi...This article outlines the development of downhole monitoring and data transmission technology for separated zone water injection in China.According to the development stages,the principles,operation processes,adaptability and application status of traditional downhole data acquisition method,cable communications and testing technology,cable-controlled downhole parameter real-time monitoring communication method and downhole wireless communication technology are introduced in detail.Problems and challenges of existing technologies in downhole monitoring and data transmission technology are pointed out.According to the production requirement,the future development direction of the downhole monitoring and data transmission technology for separated zone water injection is proposed.For the large number of wells adopting cable measuring and adjustment technology,the key is to realize the digitalization of downhole plug.For the key monitoring wells,cable-controlled communication technology needs to be improved,and downhole monitoring and data transmission technology based on composite coiled tubing needs to be developed to make the operation more convenient and reliable.For large-scale application in oil fields,downhole wireless communication technology should be developed to realize automation of measurement and adjustment.In line with ground mobile communication network,a digital communication network covering the control center,water distribution station and oil reservoir should be built quickly to provide technical support for the digitization of reservoir development.展开更多
文摘A proof-of-concept indirect tire-pressure monitoring system is developed using artificial neural networks to identify the tire pressure of a vehicle tire.A quarter-car model was developed with MATLAB and Simulink to generate simulated accelerometer output data.Simulation data are used to train and evaluate a recurrent neural network with long short-term memory blocks(RNN-LSTM)and a convolutional neural network(CNN)developed in Python with Tensorflow.Bayesian Optimization via SigOpt was used to optimize training and model parameters.The predictive accuracy and training speed of the two models with various parameters are compared.Finally,future work and improvements are discussed.
文摘This paper presents the tire pressure monitoring system (TPMS) by using the system on chip (SoC) mixed signals with the help of Bluetooth transmission and in advantage of low power consumption design. This is to monitor the variations in temperature and pressure of the vehicle’s tire, and the TPMS system is involved. It improves the driver’s safety by automatically detecting the tire pressure and temperature and then warning signal is sent to driver to take a measure, which prevents from accident. The proposed system of tire pressure monitoring system using SoC increases the speed of indication time to the driver by using mixed signals. The inflation of the tire can be avoided by preventing from high temperature and high pressure. Limitation of temperature and pressure in the previous system is also elongated i.e. temperature from 40℃ to 125℃ and pressure from 0 to 750 Kpa. Sensors, wireless communication (Bluetooth dongle) and SoC unit are used to design the low power TPMS. Quantitative results are taken and the analogy between temperature and pressure is also verified. The tested results proved by need of the practical system. Signal conditioning voltage and SoC unit is the trace for low power design TPMS. Finally, the performance of the system is tested and executed by using proteus software given as a real time application.
文摘Tyre Pressure Monitoring Systems(TPMS)are installed in automobiles to monitor the pressure of the tyres.Tyre pressure is an important parameter for the comfort of the travelers and the safety of the passengers.Many methods have been researched and reported for TPMS.Amongst them,vibration-based indirect TPMS using machine learning techniques are the recent ones.The literature reported the results for a perfectly balanced wheel.However,if there is a small unbalance,which is very common in automobile wheels,‘What will be the effect on the classification accuracy?’is the question on hand.This paper attempts to study the effect of unbalance of the wheel on the classification accuracy of an indirect TPMS system.The tyres filled with air are considered with different pressure values to represent puncture,normal,under pressure and overpressure conditions.The vibration signals of each condition were acquired and processed using machine learning techniques.The procedure is carried out with perfectly balanced wheels and known unbalanced wheels.The results are compared and presented.
基金supported by the Guangxi Natural Science Foundation of China (2020GXNSFBA297145,Guike AD23026177)the Foundation of Guilin University of Technology(GUTQDJJ6616032)+3 种基金Guangxi Key Laboratory of Spatial Information and Geomatics (21-238-21-05)the National Natural Science Foundation of China (42064002,42004025,42074035,42204006)the Innovative Training Program Foundation (202210596015,202210596402)the Open Fund of Hubei Luojia Laboratory(gran 230100020,230100019)。
文摘The potential of monitoring the movement of typhoons using the precipitable water vapor(PWV) has been confirmed. However, monitoring the movement of typhoon is focused on PWV, making it difficult to describe the movement of a typhoon in detail minutely and resulting in insufficient accuracy. Hence,based on PWV and meteorological data, we propose an improved typhoon monitoring mode. First, the European Centre for Medium-Range Weather Forecasts Reanalysis 5-derived PWV(ERA5-PWV) and the Global Navigation Satellite System-derived PWV(GNSS-PWV) were compared with the reference radiosonde PWV(RS-PWV). Then, using the PWV and atmospheric parameters derived from ERA5, we discussed the anomalous variations of PWV, pressure(P), precipitation, and wind speed during different typhoons. Finally, we compiled a list of critical factors related to typhoon movement, PWV and P. We developed an improved multi-factor typhoon monitoring mode(IMTM) with different models(i.e.,IMTM-I and IMTM-II) in different cases with a higher density of GNSS observation or only Numerical Weather Prediction(NWP) data. The IMTM was evaluated through the reference movement speeds of HATO and Mangkhut from the China Meteorological Observatory Typhoon Network(CMOTN). The results show that the root mean square(RMS) of the IMTM-I is 1.26 km/h based on ERA5-P and ERA5-PWV,and the absolute bias values are mostly within 2 km/h. Compared with the models considering the single factor ERA5-P/ERA5-PWV, the RMS of the IMTM-I is improved by 26.3% and 38.5%, respectively. The IMTM-II model manifests a residual of only 0.35 km/h. Compared with the single-factor model based on GNSS-PWV/P, the residual of the IMTM-II model is reduced by 90.8% and 84.1%, respectively. These results propose that the typhoon movement monitoring approach combining PWV and P has evident advantages over the single-factor model and is expected to supplement traditional typhoon monitoring.
文摘The phase change of CO_(2) has a significant bearing on the siting, injection, and monitoring of storage. The phase state of CO_(2) is closely related to pressure. In the process of seismic exploration, the information of formation pressure can be response in the seismic data. Therefore, it is possible to monitor the formation pressure using time-lapse seismic method. Apart from formation pressure, the information of porosity and CO_(2) saturation can be reflected in the seismic data. Here, based on the actual situation of the work area, a rockphysical model is proposed to address the feasibility of time-lapse seismic monitoring during CO_(2) storage in the anisotropic formation. The model takes into account the formation pressure, variety minerals composition, fracture, fluid inhomogeneous distribution, and anisotropy caused by horizontal layering of rock layers(or oriented alignment of minerals). From the proposed rockphysical model and the well-logging, cores and geological data at the target layer, the variation of P-wave and S-wave velocity with formation pressure after CO_(2) injection is calculated. And so are the effects of porosity and CO_(2) saturation. Finally, from anisotropic exact reflection coefficient equation, the reflection coefficients under different formation pressures are calculated. It is proved that the reflection coefficient varies with pressure. Compared with CO_(2) saturation, the pressure has a greater effect on the reflection coefficient. Through the convolution model, the seismic record is calculated. The seismic record shows the difference with different formation pressure. At present, in the marine CO_(2) sequestration monitoring domain, there is no study involving the effect of formation pressure changes on seismic records in seafloor anisotropic formation. This study can provide a basis for the inversion of reservoir parameters in anisotropic seafloor CO_(2) reservoirs.
基金Supported by the Shanghai Science Committee Project(No.Y232821D01)
文摘This paper presents an RF energy harvesting system for wireless intraocular pressure monitoring applications.The system consists of an implantable antenna and a rectifier.A new sizing strategy is adopted to optimize the conversion efficiency of the rectifier,and the design principle of an implantable antenna is introduced from material selection and structure design.Results from testing demonstrate that the antenna gain is about-20 dBi and the rectifier's maximum total conversion efficiency which contains match efficiency and rectifying efficiency is 47.18%under the implementation of0.18μm standard CMOS process.The maximum power obtained from the proposed system is 8μW when the power density of electromagnetic wave is lower than the national standard 40μW/cm^2 at915 MHz,which is enough to power the intraocular pressure monitoring system.
文摘An epidural blood patch (EBP) is a procedure performed by injecting autologous blood into a patient’s epidural space, usually at the site of a suspected CSF leak. It is typically performed in patients with characteristic postural headaches due to low intracranial pressure. We report a case of a young female with an implanted Miethke Sensor Reservoir, which was used for continuous intracranial pressure (ICP) monitoring during a two-level epidural blood patch. ICP increased only with thoracic injection, suggesting thoracic EBP may have greater efficacy than lumbar EBP in treating SIH and PDPH when the site of CSF leak is unknown.
基金support by the Science Fund of Shandong Laboratory of Advanced Materials and Green Manufacturing at Yantai(AMGM2021A03)the"Special Lubrication and Sealing for Aerospace"Shaanxi Provincial Science and Technology Innovation Team(2024RS-CXTD-63)+1 种基金the Xianyang2023 Key Research and Development Plan(L2023-ZDYF-QYCX-009)the World First Class University and First Class Academic Discipline Construction Funding 2023(0604024GH0201332,0604024SH0201332).
文摘Flexible and wearable pressure sensors hold immense promise for health monitoring,covering disease detection and postoperative rehabilitation.Developing pressure sensors with high sensitivity,wide detection range,and cost-effectiveness is paramount.By leveraging paper for its sustainability,biocompatibility,and inherent porous structure,herein,a solution-processed all-paper resistive pressure sensor is designed with outstanding performance.A ternary composite paste,comprising a compressible 3D carbon skeleton,conductive polymer poly(3,4-ethylene dioxythiophene):poly(styrenesulfonate),and cohesive carbon nanotubes,is blade-coated on paper and naturally dried to form the porous composite electrode with hierachical micro-and nano-structured surface.Combined with screen-printed Cu electrodes in submillimeter finger widths on rough paper,this creates a multiscale hierarchical contact interface between electrodes,significantly enhancing sensitivity(1014 kPa-1)and expanding the detection range(up to 300 kPa)of as-resulted all-paper pressure sensor with low detection limit and power consumption.Its versatility ranges from subtle wrist pulses,robust finger taps,to large-area spatial force detection,highlighting its intricate submillimetermicrometer-nanometer hierarchical interface and nanometer porosity in the composite electrode.Ultimately,this all-paper resistive pressure sensor,with its superior sensing capabilities,large-scale fabrication potential,and cost-effectiveness,paves the way for next-generation wearable electronics,ushering in an era of advanced,sustainable technological solutions.
文摘Objective:To explore the effect of continuous non-invasive blood pressure monitoring on intraoperative hemodynamics and postoperative myocardial injury in craniotomy.Methods:120 cases of elective craniotomy were divided into the self-control group(continuous non-invasive blood pressure monitoring and intermittent cuff non-invasive blood pressure monitoring,CNAP group)and propensity score matching group(only intermittent cuff non-invasive blood pressure measurement in previous craniotomy,PSM group);Goal-directed hemodynamic management in CNAP group included heart rate(HR),blood pressure(BP),stroke volume(SV),stroke variability(SVV),and systemic vascular resistance index(SVRI).The main index is to compare the troponin level within 72 hours after operation between the CNAP group and the PSM group;The secondary indicators are the comparison of the hemodynamic conditions between the CNAP group and the PSM at 10 specific time points.Results:The incidence of postoperative myocardial injury in the CNAP group was significantly lower than that in the PSM group(12%vs.30%,P=0.01);in the CNAP group hypotensive episodes(6 vs.3,P=0.01),positive balance of fluid therapy(700 vs.500 mL,P<0.001),more use of vasoactive drugs(29 vs.18,P=0.04),more stable hemodynamics medical status(P=0.03)were recorded.Conclusion:The hemodynamic management strategy based on continuous non-invasive blood pressure monitoring can reduce the incidence of myocardial injury after elective craniotomy and maintain a more stable hemodynamic state.
基金supported by the Opening Foundation of State Key Laboratory of Automobile Safety and Energy,Tsinghua University,China(Grant No. KF2005-11,Grant No.KF2007-09)
文摘Monitoring tire pressure of cars and signaling abnormal conditions is an important means to prevent deadly accidents. Large achievements have been gained, especially in direct tire pressure monitoring system(TPMS). But there has been rarely research on indirect TPMS in the world. In China, the research on indirect TPMS is almost lacking. The international research on the indirect monitoring tire pressure method is mainly based on measuring and comparing the rotating speed of wheels. But it is very difficult to measure wheel rotating speed accurately because of the influence of many random factors. In this paper, the authors propose a new method in which the tire pressure can be monitored indirectly. This method can be used for tire calibration, wheel speed frequency standardization, wheel speed frequency comparison, and abnormal tire pressure determination. The pulse frequencies from wheel speed sensors of ABS are used to indicate tire deformation. Because the frequency has a relationship with tire deformation, the tire deformation reflects the tire pressure. Small sample statistics is used in the new method to increase the accuracy, and the experimental samples using the principle of the new method have been made and tested. The result of vehicle tests on road demonstrates that the method is efficient and accurate to monitor tire pressure. The research has positive potential for developing products.
基金Project(SKLCRSM12X01)supported by State Key Laboratory of Coal Resources and Safe Mining,China University of Mining&TechnologyProject(2014ZDPY02)supported by the Fundamental Research Funds for the Central Universities,ChinaProject(CXLX13_951)supported by the Research Innovation Program for College Graduates of Jiangsu Province,China
文摘Fully mechanized solid backfill mining(FMSBM) technology adopts dense backfill body to support the roof. Based on the distinguishing characteristics and mine pressure control principle in this technology, the basic principles and methods for mining pressure monitoring were analyzed and established. And the characteristics of overburden strata movement were analyzed by monitoring the support resistance of hydraulic support, the dynamic subsidence of immediate roof, the stress of backfill body, the front abutment pressure, and the mass ratio of cut coal to backfilled materials. On-site strata behavior measurements of 7403 W solid backfilling working face in Zhai Zhen Coal Mine show that the backfill body can effectively support the overburden load, obviously control the overburden strata movement, and weaken the strata behaviors distinctly. Specific performances are as follows. The support resistance decreases obviously; the dynamic subsidence of immediate roof keeps consistent to the variation of backfill body stress, and tends to be stable after the face retreating to 120-150 m away from the cut. The peak value of front abutment pressure arises at 5-12 m before the operating face, and mass ratio is greater than the designed value of 1.15, which effectively ensures the control of strata movement. The research results are bases for intensively studying basic theories of solid backfill mining strata behaviors and its control, and provide theoretical guidance for engineering design in FMSBM.
文摘Background Fall injuries are common among the elderly. The aim of this study was to investigate whether blood-pressure patterns, as measured by 24-h ambulatory blood pressure monitoring (ABPM), or intensification of antihypertensive therapy following the 24-h ABPM, may be associated with fall injuries in hypertensive elderly patients. Methods In a retrospective study, community-based elderly patients (age ≥ 70 years) who were referred to 24-h ABPM were evaluated for fall injuries within one-year post-ABPM. We compared the clinical characteristics, 24-h ABPM patterns and the intensification of hypertensive therapy following 24-h ABPM, between patients with and without a fall injury. Results Overall 1032 hypertensive elderly patients were evaluated. Fifty-five (5.3%) had a fall injury episode in the year following ABPM. Patients with a fall injury were significantly older, and with higher rates of previous falls. Lower 24-h diastolic blood-pressure (67.3 ± 7.6 vs. 70.7 ± 8.8 mmHg; P 〈 0.005) and increased pulse-pressure (74.7 ± 14.3 vs. 68.3 ± 13.7 mmHg; P 〈 0.005), were found in the patients with a fall injury, compared to those without a fall injury. After adjustment for age, gender, diabetes mellitus and previous falls, lower diastolic blood-pressure and increased pulse-pressure were independent predictors of fall injury. Intensification of antihypertensive treatment following the 24-h ABPM was not associated with an increased rate of fall injury. Conclusions Low diastolic blood-pressure and increased pulse-pressure in 24-h ABPM were associated with an increased risk of fall injury in elderly hypertensive patients. Intensification of antihypertensive treatment following 24-h ABPM was not associated with an increased risk of fall injury.
文摘Despite an increasing popularity of home blood pressure monitoring (HBPM) over the last few decades, little is known about HBPM use among hypertensive patients in the rural areas. A cross-sectional survey including 318 hypertensive patients was conducted in a rural community in Beijing, China, in 2012. Participants were mainly recruited from a community health clinic and completed the questionnaires assessing HBPM usage. Binary logistic regression models were used for the analysis of medication adherence with age, gender, level of education marital status, perceived health status, duration of hypertension, HBPM use, and frequency of performing BP measurement. Among the total population, 78 (24.5%) reported currently use of HBPM. Only 5.1% of the HBPM users cited doctor’s advice as the reason for using HBPM. Analysis of the risk factors of poor medication adherence by multivariable modeling indicated significant associations between the duration of hypertension (adjusted OR, 3.31;95% CI, 1.91-5.72;P 01), frequency of performing BP measurements (adjusted OR, 2.33;95% CI, 1.42-3.83;
基金supported by a grant from Shanghai Municipal Health Bureau Program(2009143)
文摘BACKGROUND: Noninvasive monitoring of intra-abdominal pressure(IAP) by measuring abdominal wall tension(AWT) was effective and feasible in previous postmortem and animal studies. This study aimed to investigate the feasibility of the AWT method for noninvasively monitoring IAP in the intensive care unit(ICU).METHODS: In this prospective study, we observed patients with detained urethral catheters in the ICU of Shanghai Tenth People's Hospital between April 2011 and March 2013. The correlation between AWT and urinary bladder pressure(UBP) was analyzed by linear regression analysis. The effects of respiratory and body position on AWT were evaluated using the paired samples t test, whereas the effects of gender and body mass index(BMI) on baseline AWT(IAP<12 mm Hg) were assessed using one-way analysis of variance.RESULTS: A total of 51 patients were studied. A significant linear correlation was observed between AWT and UBP(R=0.986, P<0.01); the regression equation was Y=–1.369+9.57X(P<0.01). There were signif icant differences among the different respiratory phases and body positions(P<0.01). However, gender and BMI had no signif icant effects on baseline AWT(P=0.457 and 0.313, respectively).CONCLUSIONS: There was a signif icant linear correlation between AWT and UBP and respiratory phase, whereas body position had signif icant effects on AWT but gender and BMI did not. Therefore, AWT could serve as a simple, rapid, accurate, and important method to monitor IAP in critically ill patients.
文摘This article is a review of 25 publications on ambulatory blood pressure monitoring(ABPM) and the importance of its results in everyday clinical practice. These studies, published in 2008-2011, were selected from the Scopus database, but are also available in Pubmed. They were prepared by researchers from around the world, concerned with the problems of proper control of blood pressure(BP), and of abnormalities in the circadian pattern of BP in patients with arterial hypertension, diabetes mellitus or renal failure. In the first part of this article, I analyse publications focused on some nuances in the methodology of ABPM and recommend ways to avoid some traps, related not only to the individual patient but also to the device used and the technical staff. The next section is devoted to the advantages of ABPM as a diagnostic tool which enables clinicians to learn about patients' BP during sleep, and emphasizes the practical implications of this information for so-called chronotherapy. This section also presents some new studies on the prognostic value of ABPM in patients with cardiovascular(CV) risk. Some recent articles on the results of various methods of pharmacological treatment of arterial hypertension in different agegroups are then described. The observations presented in this article may be helpful not only for researchers interested in the chronobiology of the CV system, but also for general practitioners using ABPM.
文摘Heart failure (HF) is an emerging epidemic associate with significant morbidity, mortality, and health care expenditure. Although there were major advances in pharmacologic and device based therapies for the management of HF, mortality of this condition remains high. Accurate monitoring of HF patients for exacerbations is very important to reduce recurrent hospitalizations and its associated complications. With the failure of clinical signs, tele-monitoring, and laboratory bio-markers to function as early markers of HF exacerbations, more sophisticated techniques were sought to accurately predict the circulatory status in HF patients in order to execute timely pharmacological intervention to reduce frequent hospitalizations. CardioMEMS<sup>TM</sup> (St. Jude Medical, Inc., Saint Paul, Minnesota) is an implantable, wireless pulmonary arterial pressure (PAP) monitoring system which transmits the patient’s continuous PAPs to the treating health care provider in the ambulatory setting. PAP-guided medical therapy modification has been shown to significantly reduce HF-related hospitalization and overall mortality. In advanced stages of HF, wireless access to hemodynamic information correlated with earlier left ventricular assist device implantation and shorter time to heart transplantation.
基金We gratefully acknowledge financial support from the National Natural Science Foundation of China(NSFC)(No.51704097)Science Foundation of Henan Polytechnic University(No.J2021–2)+1 种基金Key Research and Development Program of Henan Province,China(No.202102310244)“Science and Technology to Help the Economy 2020”Key Project(No.SQ2020YFF0426364).
文摘The wide pillars are generally popular due to the high productivity and efficiency in Northwest China.The distribution of lateral abutment pressure in coal pillars is important for mining safety.To reveal the effect of the first mining on the lateral abutment pressure distribution and evolution in wide pillars,an in-situ experiment,theoretical analysis and numerical simulation were performed.First,the field monitoring of lateral abutment pressure was conducted from the perspective of time and space in the Chahasu Coal Mine,Huangling No.2 Coal Mine and Lingdong Coal Mine during the first mining.Based on the field monitoring stress,a theoretical model was proposed to reveal the lateral abutment pressure distribution.The methodology was demonstrated through a case study.Aiming at the distribution mechanism,a numerical experiment was conducted through the finite-discrete element method(FDEM).Last,field observations of borehole fractures were performed to further study the damage distribution.In addition,two types of lateral abutment pressure evolution with mining advance were discussed.Suggestions on the stress monitoring layout were proposed as well.The results could provide foundations for strata control and disaster prevention in wide pillars in underground coal mines.
文摘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.
文摘Background HIRFL is a heavy ion accelerator built by the Institute of Modern Physics,Chinese Academy of Sciences,which constitutes a total length of over 900 m by the SFC,SSC,CSRm,CSRe and so on.It bears a lot of research task of the country,so to ensure its safe operation is very important.Purpose Cool-water system is a key part in HIRFL,and the parameters of the cool-water system need to be monitored before an accident occurs.Methods This article describes three aspects of the system,from the water leakage detection,pressure monitoring,to the water-level monitoring.A complete monitor system was designed and constructed,including the hardware structure;the data transfer mode,as well as specific control program.C++,FLASH and SCADA are used in the monitoring system.Results Fault alarm was performed timely and accurately by the monitoring system,and many accidents were avoided.Conclusion Water system monitoring is an important part of the accelerator control system.It will also play a major role in the construction of large-scale scientific device named HIAF in the further.
基金Supported by the National Natural Science Foundation Science Center Project/Basic Science Center Project(72088101)PetroChina Scientific Research and Technology Development Project(2020B-4119,2021ZG12).
文摘This article outlines the development of downhole monitoring and data transmission technology for separated zone water injection in China.According to the development stages,the principles,operation processes,adaptability and application status of traditional downhole data acquisition method,cable communications and testing technology,cable-controlled downhole parameter real-time monitoring communication method and downhole wireless communication technology are introduced in detail.Problems and challenges of existing technologies in downhole monitoring and data transmission technology are pointed out.According to the production requirement,the future development direction of the downhole monitoring and data transmission technology for separated zone water injection is proposed.For the large number of wells adopting cable measuring and adjustment technology,the key is to realize the digitalization of downhole plug.For the key monitoring wells,cable-controlled communication technology needs to be improved,and downhole monitoring and data transmission technology based on composite coiled tubing needs to be developed to make the operation more convenient and reliable.For large-scale application in oil fields,downhole wireless communication technology should be developed to realize automation of measurement and adjustment.In line with ground mobile communication network,a digital communication network covering the control center,water distribution station and oil reservoir should be built quickly to provide technical support for the digitization of reservoir development.