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This study introduces an innovative approach to pressure sensing in sports training using amorphous silicon nanostructure-based sensors. These sensors demonstrated high sensitivity (0.75 Ω/kPa) and a broad pressure detection range (1–100 kPa), making them ideal for capturing the nuances of athletic movements. Their compact size (5 mm×5 mm) and superior durability (over 5000 cycles with minimal performance variation) allowed for seamless integration into athletic shoes and attire. The sensors effectively captured pressure patterns in running, such as heel strikes peaking at 300 kPa, and cycling, revealing a 200 kPa increase in the perineal region during posture shifts. Comparative analysis highlighted the advantages of amorphous silicon nanostructure sensors over existing technologies, including higher sensitivity, wider pressure range, smaller size, and better durability. The integration of these sensors provided invaluable data for optimizing training regimes and preventing injuries. The study also delved into the physical and chemical characterization of the nanostructures, confirming their uniform size distribution, surface morphology, and amorphous nature, which contributed to their exceptional sensing performance. The findings underscore the immense potential of amorphous silicon nanostructure sensors in revolutionizing athletic performance analysis and injury prevention, offering a significant upgrade over current technologies in terms of accuracy, adaptability, and user-friendliness. This research paves the way for more sophisticated, precise, and athlete-centric pressure sensing solutions, transforming the landscape of sports technology and biomechanical assessment. [ABSTRACT FROM AUTHOR]

This paper proposes a high-precision interventional pressure measurement catheter with a compact structure for in vivo pressure monitoring. This catheter uses a minimally invasive testing method, and the proposed compact structure reduces pressure loss caused by fluid movement inside the catheter, ensuring accuracy in dynamically varying pressure measurements. The paper conducts a theoretical analysis of the pressure transmission process inside the catheter, fabricates a prototype, and establishes both dynamic and static pressure testing systems. Through experimental research on the effects of the catheter's dimensions on the accuracy of dynamically varying pressure measurements, it demonstrates that the compact pressure measurement catheter can effectively enhance the precision of dynamically varying pressure measurements. The catheter offers high precision, small size, and simple manufacturing processes. It holds promising applications in fields such as in-body pressure measurement and microfluidic system monitoring. [ABSTRACT FROM AUTHOR]

Adolescent idiopathic scoliosis is the deformity of the human spine in three-dimensional space. It is a disease with a long course and difficult to recover in a short time. Currently, spinal orthotic braces are an effective non-surgical treatment for this condition. However, existing spinal orthotic braces are still deficient. For example, existing spinal orthotics braces have no way of knowing how correct, effective, and comfortable a patient is wearing the orthotics. Based on distributed pressure monitoring technology, this paper conducts pressure acquisition and compensation research on spinal orthotics used by adolescent patients. After analyzing the principles of orthopedics and selecting monitoring points, this paper selects appropriate sensors and calibrates them. An intelligent wearable system for adolescent spinal orthotics was developed based on these findings. The experimental results show that the system can effectively monitor the process of patients wearing spinal orthotic braces. In addition, the system can compensate and visualize the pressure in real-time, so that doctors and patients can know the process and make judgments and adjustments. [ABSTRACT FROM AUTHOR]

Understanding the behavior of pressure increases in lithium-ion (Li-ion) cells is essential for prolonging the lifespan of Li-ion battery cells and minimizing the safety risks associated with cell aging. This work investigates the effects of C-rates and temperature on pressure behavior in commercial lithium cobalt oxide (LCO)/graphite pouch cells. The battery is volumetrically constrained, and the mechanical pressure response is measured using a force gauge as the battery is cycled. The effect of the C-rate (1C, 2C, and 3C) and ambient temperature (10 °C, 25 °C, and 40 °C) on the increase in battery pressure is investigated. By analyzing the change in the minimum, maximum, and pressure difference per cycle, we identify and discuss the effects of different factors (i.e., SEI layer damage, electrolyte decomposition, lithium plating) on the pressure behavior. Operating at high C-rates or low temperatures rapidly increases the residual pressure as the battery is cycled. The results suggest that lithium plating is predominantly responsible for battery expansion and pressure increase during the cycle aging of Li-ion cells rather than electrolyte decomposition. Electrochemical impedance spectroscopy (EIS) measurements can support our conclusions. Postmortem analysis of the aged cells was performed using scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDS) to confirm the occurrence of lithium plating and film growth on the anodes of the aged cells. This study demonstrates that pressure measurements can provide insights into the aging mechanisms of Li-ion batteries and can be used as a reliable predictor of battery degradation. [ABSTRACT FROM AUTHOR]

This study introduces an innovative approach to pressure sensing in sports training using amorphous silicon nanostructure-based sensors. These sensors demonstrated high sensitivity (0.75 Ω/kPa) and a broad pressure detection range (1–100 kPa), making them ideal for capturing the nuances of athletic movements. Their compact size (5 mm×5 mm) and superior durability (over 5000 cycles with minimal performance variation) allowed for seamless integration into athletic shoes and attire. The sensors effectively captured pressure patterns in running, such as heel strikes peaking at 300 kPa, and cycling, revealing a 200 kPa increase in the perineal region during posture shifts. Comparative analysis highlighted the advantages of amorphous silicon nanostructure sensors over existing technologies, including higher sensitivity, wider pressure range, smaller size, and better durability. The integration of these sensors provided invaluable data for optimizing training regimes and preventing injuries. The study also delved into the physical and chemical characterization of the nanostructures, confirming their uniform size distribution, surface morphology, and amorphous nature, which contributed to their exceptional sensing performance. The findings underscore the immense potential of amorphous silicon nanostructure sensors in revolutionizing athletic performance analysis and injury prevention, offering a significant upgrade over current technologies in terms of accuracy, adaptability, and user-friendliness. This research paves the way for more sophisticated, precise, and athlete-centric pressure sensing solutions, transforming the landscape of sports technology and biomechanical assessment.

Pressure monitoring on pediatric Extracorporeal Membrane Oxygenation (ECMO) circuits is used to aid in the evaluation of patient hemodynamics and circuit health. Extracorporeal Life Support Organization (ELSO) recommends monitoring pressures on the venous line, pre-, and post-oxygenator. In order to keep pressure ports patent, crystalloid can be used as a flush. The fluid transfused to the patient through these lines can be challenging to quantify accurately due to variance in clinician practice. Currently, there is no published data or practice suggestions on this topic. In Vitro experiments using Edwards True Wave transducers and pressure bags were constructed, allowing for common negative and positive pressures to be simulated. Passive volume infused through the transducer as well as intermittent active flushing by pulling the snap tab were measured and the volumes were recorded. When the pressure transducer and associated tubing are kept patent by using a pressurized IV bag, per the instructions for use, the daily volume transfused was found to be 319.6 mL or close to a typical neonate’s total blood volume. Rather than using passive or active flushing, the use of automated syringe pumps can reduce the transfused volume to 24 mL per day. Further study is recommended to develop and publish best practices.

Purpose: Compartment syndrome remains difficult to diagnose early in its clinical course. Pressure transducer catheters have been used to directly measure intracompartmental pressure (ICP), but this method is unreliable, with a false positive rate of 35%. We have previously used intramuscular near infrared spectroscopy to detect changes in tissue oxygen saturation (StO2) in response to increasing ICP using a novel implantable probe. However, measuring StO2 may not be sufficient to identify CS in the clinical setting. The pathophysiology of CS consists of increased ICP, leading to decreased tissue perfusion, and resulting in reduced tissue oxygenation. More clinically useful information may come from the integration of multiple data streams to aid in the diagnosis of CS. In this study, we present a novel, intramuscular probe capable of simultaneous measurement of ICP, StO2, and microvascular blood flow in a porcine model of ACS. Methods: Proof of concept for this device is demonstrated in a porcine lower extremity balloon compression model of ACS. Pressure was maintained for 20 min (short-term) or 3 h (long-term) before the balloon volume was removed. Results: In both short- and long-term experiments, as ICP increased with increasing balloon volume, the novel multimodal sensor simultaneously and reliably detected pressure elevation and corresponding reversible reductions in microvascular flow rate and tissue oxygenation. Conclusion: This novel trimodal device simultaneously measured the elevated ICP, decreased perfusion, and tissue ischemia of evolving ACS, substantiating our basic understanding of CS pathophysiology. [ABSTRACT FROM AUTHOR]

This paper introduces a novel methodology that integrates low‐ and high‐frequency pressure monitoring in the parts of the urban water distribution network characterized by the largest number of repairing operations. This integrated approach aims to pinpoint the source and characterize potentially dangerous pressure variations. The actual behavior of a real operational water distribution network is considered as an example to verify the effectiveness of the proposed methodology. The analysis of the acquired pressure signals allows for mapping frequent pressure surges and identifying their source in the functioning conditions of a big user. Notwithstanding these pressure variations are not overly large, according to the literature, their near‐continuous nature poses a risk of inducing pipe breaks, and then leakage, due to fatigue. The proposed method integrating routine low‐frequency measurements with targeted high‐frequency surveys provides a cost‐effective, proactive management strategy. Key Points: A method is proposed for detecting transient source in Urban Water Distribution NetworksLow‐frequency pressure monitoring initially identifies the most pressure‐stressed section in a high‐maintenance areaHigh‐frequency pressure monitoring allows localizing the transient source [ABSTRACT FROM AUTHOR]

This work presents the reconstruction of the pressure head map of a water distribution system (WDS). This approach relies on historical data collected from a reduced number of sensors placed at some nodes of the WDS. Thus, a Gaussian regression process is then applied to estimate the pressure head at those nodes without a sensor, which allows the reconstruction of the pressure map for the whole network. Then, for leak diagnosis purposes, a dataset of pressure head maps of the WDN is created considering leaky scenarios, and a correlation method is applied to estimate the leak location. Then, for clarity, the Hanoi network is used to evaluate the performance of this leak diagnosis strategy in a simulation environment, assuming the availability of only three sensors. The results showed the potential for pressure head map reconstruction and leak localization. [ABSTRACT FROM AUTHOR]

Extracorporeal membrane oxygenation (ECMO) is a life-support technique used to treat cardiac and pulmonary failure, including severe cases of COVID-19 (coronavirus disease 2019) involving acute respiratory distress syndrome. Blood clot formation in the circuit is one of the most common complications in ECMO, having potentially harmful and even fatal consequences. It is therefore essential to regularly monitor for clots within the circuit and take appropriate measures to prevent or treat them. A review of the various methods used by hospital units for detecting blood clots is presented. The benefits and limitations of each method are discussed, specifically concerning detecting blood clots in the oxygenator, as it is concluded that this is the most critical and challenging ECMO component to assess. We investigate the feasibility of solutions proposed in the surrounding literature and explore two areas that hold promise for future research: the analysis of small-scale pressure fluctuations in the circuit, and real-time imaging of the oxygenator. It is concluded that the current methods of detecting blood clots cannot reliably predict clot volume, and their inability to predict clot location puts patients at risk of thromboembolism. It is posited that a more in-depth analysis of pressure readings using machine learning could better provide this information, and that purpose-built imaging could allow for accurate, real-time clotting analysis in ECMO components. [ABSTRACT FROM AUTHOR]

This paper proposes a high-precision interventional pressure measurement catheter with a compact structure for in vivo pressure monitoring. This catheter uses a minimally invasive testing method, and the proposed compact structure reduces pressure loss caused by fluid movement inside the catheter, ensuring accuracy in dynamically varying pressure measurements. The paper conducts a theoretical analysis of the pressure transmission process inside the catheter, fabricates a prototype, and establishes both dynamic and static pressure testing systems. Through experimental research on the effects of the catheter’s dimensions on the accuracy of dynamically varying pressure measurements, it demonstrates that the compact pressure measurement catheter can effectively enhance the precision of dynamically varying pressure measurements. The catheter offers high precision, small size, and simple manufacturing processes. It holds promising applications in fields such as in-body pressure measurement and microfluidic system monitoring.

Understanding the behavior of pressure increases in lithium-ion (Li-ion) cells is essential for prolonging the lifespan of Li-ion battery cells and minimizing the safety risks associated with cell aging. This work investigates the effects of C-rates and temperature on pressure behavior in commercial lithium cobalt oxide (LCO)/graphite pouch cells. The battery is volumetrically constrained, and the mechanical pressure response is measured using a force gauge as the battery is cycled. The effect of the C-rate (1C, 2C, and 3C) and ambient temperature (10 °C, 25 °C, and 40 °C) on the increase in battery pressure is investigated. By analyzing the change in the minimum, maximum, and pressure difference per cycle, we identify and discuss the effects of different factors (i.e., SEI layer damage, electrolyte decomposition, lithium plating) on the pressure behavior. Operating at high C-rates or low temperatures rapidly increases the residual pressure as the battery is cycled. The results suggest that lithium plating is predominantly responsible for battery expansion and pressure increase during the cycle aging of Li-ion cells rather than electrolyte decomposition. Electrochemical impedance spectroscopy (EIS) measurements can support our conclusions. Postmortem analysis of the aged cells was performed using scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDS) to confirm the occurrence of lithium plating and film growth on the anodes of the aged cells. This study demonstrates that pressure measurements can provide insights into the aging mechanisms of Li-ion batteries and can be used as a reliable predictor of battery degradation.

Introduction: For safe management of cell‐free and concentrated ascites reinfusion therapy (CART), a highly reliable leak test for detecting ascites filter damage is essential. However, such a test has not been established for drop‐type CART. Methods: We devised two novel leak tests for drop‐ and external pressure‐type CART, manual or pump pressurization methods, using high‐pressure loading and pressure monitoring, and investigated their reliability. Results: Both methods could easily load and maintain sufficiently high pressure (>400 Torr) on the hollow fibers for 2 min. No result deviation was noted between different operators. The pressure drops in both methods were identical and significantly lower than those in the leak test using a special CART machine, the e‐CART. Conclusion: The reliability of our revised leak test is equivalent to that of the automatic leak test of e‐CART. These highly reliable leak tests may contribute to safety in patients undergoing drop‐ and external pressure‐type CART. [ABSTRACT FROM AUTHOR]

Blood sampling typically involves puncturing a superficial vein with a needle and then creating a vacuum (e. g., with a syringe) to transfer the blood from the venous system to the collection container. In some cases, the venous walls collapse due to excessive vacuum generated. In this work, a device is presented that prevents venous collapse and can be combined with any blood collection system available on the market. The mechanism of preventing venous collapse is based on a tubular segment interconnected between the needle and the syringe, which collapses at a lower vacuum pressure than the vein. The prototype was tested and evaluated using a test rig that simulates venous blood draw. The experiments proved the functionality of the device on a vein phantom.

Problem. On the condition of the tires and their correct choice depending on the weather conditions, first of all, the indicators of many operational properties of the car depend. The internal pressure and temperature of the tire increases during driving, as a result, there is a significant effect on the rolling resistance of the tire. At high values of the rolling resistance coefficient, first of all, fuel consumption increases, tire wear increases, etc. It is important to know how the rolling resistance coefficient changes during the starting period of motion. Goal. The purpose of this work is to determine the starting mode of motion time for specific vehicles. Based on the obtained dependences of the internal pressure and temperature of the tire on time, it is necessary to evaluate how the rolling resistance coefficient changes. Methodology. As a result of experimental studies, on vehicles equipped with tires of various sizes and seasonality, the dependences of the pressure and temperature of the tire material at three points (tread zone, shoulder part and sidewall) were obtained. Using the results of the experiment, as well as based on the dependencies presented in scientific papers devoted to the study of the performance characteristics of car tires, an indirect assessment of the rolling resistance coefficient when driving in the starting mode is made. Results. The value of the increase in the internal pressure of the gas filler in the tire has been established and the driving time for the studied vehicles in the starting mode has been determined. The most intense temperature rise is observed in the shoulder area of the tires. The temperature of the surface layer of winter tires increases less than summer tires, and, accordingly, driving on winter tires is safer at temperatures close to 0°C and below. Originality. A technique for indirectly assessing the rolling resistance of a car tire when driving in the starting mode (on "cold" tires) is presented, that is, knowing how the internal air pressure and tire temperature change, it is possible to predict a change in the rolling resistance coefficient. Practical value. Using the dependences obtained as a result of an indirect assessment of the rolling resistance of car tires, one can judge the value of the rolling resistance coefficient without resorting to experiments. The well-known assertion that it is necessary to timely replace summer tires with winter ones (when the ambient temperature can reach +5 ° C and lower) is confirmed, thereby significantly improving road safety.

The regulation of the seasonal energy supply for natural gas and the storage of fossil energy are important to society. To achieve it, storing a large amount of natural gas in porous underground media is one of the government's choices. Due to the successful lesson learned from the oil and gas industry, natural gas storage in underground porous media has been regarded as the most potential long−term energy storage method. In this paper, we developed a new workflow to evaluate the performance of gas reservoir−type underground natural gas storage (UGS). The theoretical background of this workflow includes the correction of the average formation pressure (AFP) and gas deviation factor by error theory and the analytical mathematical model of UGS wells. The Laplace transform, line source function, and Stehfest numerical inversion methods were used to obtain pressure solutions for typical vertical and horizontal wells in UGS. The pressure superposition principle and weighting method of the gas injection−withdrawal rate were used to obtain the AFP. Through the correction of the AFP and gas deviation factor in the material balance equation, the parameters for inventory, effective inventory (the movable gas volume at standard condition), working gas volume (the movable gas volume is operated from the upper limit pressure to the lower limit pressure), and effective gas storage volume (the available gas storage volume at reservoir condition) were determined. Numerical data from the numerical simulator was used to verify the proposed model pressure solution. Actual data from China's largest Hutubi UGS was used to illustrate the reliability of the proposed workflow in UGS performance evaluation. The results show that large−scale gas injection and withdrawal rates lead to composite heterogeneity in gas storage wells. The nine injection and production cycles' pressure and effective inventory changes from Hutubi UGS can be divided into a period of rapid pressure rise and a period of slow pressure increase. The final AFP is 32.8 MPa. The final inventory of the Hutubi UGS is 100.1 × 108 m3, with a capacity filling rate (the ratio of effective inventory to designed gas storage capacity) of 93.6%. The effective inventory is 95.3 × 108 m3, and the inventory utilization ratio (the ratio of effective inventory to inventory) is 95.2%. The working gas volume is 40.3 × 108 m3. This study provides a new method for inventory evaluation of the gas reservoir−type UGS. [ABSTRACT FROM AUTHOR]

We assess the range of pressures exerted by haemostatic compression bandages on upper limb arterial injuries. Maintaining a pink hand can act as a safety marker to prevent excessive bandage pressure and avert compression injuries. [ABSTRACT FROM AUTHOR]

A new method of identifying the validity of pressure sensor readings has been developed. The method uses duplication of measurements which allows an estimation of the magnitude of an error, although it does not make it possible to establish which sensor is responsible for the error. The method helps to evaluate the systematic error magnitude and to test whether the error exists within a permission range accounting for a correlation structure of measurement series. An autoregressive model with a drift coefficient is applied to investigate a time series of the differences in readings. To test the significance of this coefficient, a modified Student’s test is used. Unlike the standard Student’s test, this new method tests an interval hypothesis. The null hypothesis assumes the systematic error is within the range and the alternative is out of the range. Error probabilities of type I and type II are calculated. An example of 2nd order autoregressive model was considered and the sensitivity of the proposed method was investigated.

This article proposes a novel wireless, battery-free, and label-free biosensor for minimally invasive and noninvasive permittivity sensing for applications, such as detecting glucose levels in the interstitial dermal fluid. The miniaturized, fully passive sensor is based on two symmetric parallel 0.8 mm3 inductor–capacitor ($LC$) resonators. Each inductor is integrated with a conductive plate at one of its terminals. The main field of the passive sensor is outside the resonators, creating an effective capacitance outside the sensor, unlike reported in previous studies, where the effective capacitance was limited between the resonator lines. The proposed sensor was further analyzed under two different scenarios to change the region of effective capacitance and test its suitability for pressure monitoring, such as wound monitoring; first, by repositioning one of the two resonators, and second, by replacing one of the resonators with a conductive plate. The experimental results confirmed the proposed passive sensor’s performance in detecting the glucose concentration in an aqueous solution with a sensitivity of 500 and 46 kHz/(mg/dL) for minimal invasive and noninvasive monitoring, respectively, within the glucose range of 0–500 mg/dL with volume sample requirements as low as 60 $\mu \text{L}$. Furthermore, by repositioning one of the resonators, the effective capacitance lies inside the passive sensor, making it suitable for wound monitoring. The results indicated that the shift in the resonant frequency can be made fairly linear with respect to the variation in the separation between the resonators with a sensitivity of $2.5\times 10^{3}$ MHz/mm within the separation range of 0.2–0.5 mm, considering separation as the main factor to sense the pressure or healing of the wound. [ABSTRACT FROM AUTHOR]

Gas is one of the main factors causing coal mine accidents in China. Understanding the mechanism of the influence of mine pressure on coal seam gas emission has important theoretical guiding significance for coal mine enterprises to be able to control gas. This paper chose the 72,909 working face in the Du'erping coal mine as the engineering background, analyzed the characteristics of the mine pressure in the working face and the driving face through numerical simulation, and found that the power of the gas emission in the working face is the mine pressure, while that of gas emission in the driving face is the gas pressure gradient. Based on the field monitoring data of the hydraulic support in the working face and the single pillar in the mining roadway, the law of mine pressure was obtained. Combined with the monitoring data of the number of drill cuttings and gas in different positions of the mining roadway and the gas concentration change in the upper corner of the working face during mining, the influence of the advanced support pressure and periodic pressure on the gas emission of the coal seam was analyzed. The results show that the advanced support pressure affects the coal seam gas emission by affecting the coal seam permeability coefficient. With the increase in the support pressure, the coal seam permeability coefficient decreases, and the coal seam gas emission decreases. During the period of periodic pressure, the advanced support pressure moves forward, forming a pressure relief zone in front of the working face, which is conducive to the emission of coal seam gas, and periodic pressure provides power for the gas emission. [ABSTRACT FROM AUTHOR]

The water pressure monitoring system in the PDAM pipeline networks has been successfully developed for operation and maintenance of water leaks in a real-time manner. This research aims to design a water pressure monitoring system in operational piping networks to identify anomalies as early as possible. The system is built using a microcontroller, a 1.2 MPa fluid pressure sensor and a control system equipped with a GSM wireless communication module, an Analog to Digital Converter module with 16-bit resolution, a real-time clock peripheral, an OLED display 128x64, and a micro SD card. The developed system was tested in a pressure range of 0.200 - 0.800 bar with 30 repetitions with a RMSE of 0.058 bar. This system has a deterministic coefficient of 0.885 against a standard manometer. The system implemented in the field successfully sends data to the server with a success rate of 96.0%. Data is displayed on a monitoring dashboard that can be accessed via a computer or smartphone.

With the growing use of stent implantations, the risk of in-stent restenosis represents a major concern for cardiovascular patients. Herein, we propose a hybrid bioresorbable vascular scaffold (H-BVS) integrated with a wireless sensor that could enable significant advances in cardiovascular therapeutics. The H-BVS was carefully manufactured using a state-of-the-art customized 3D printer equipped with dual nozzles to achieve a synergistic combination of polycaprolactone (PCL) and polylactic acid (PLA), both of which are known for their bioresorbable properties. This characteristic is particularly valuable in medical applications where the scaffold is gradually absorbed by the body, eliminating the need for a second procedure to remove it. Furthermore, the H-BVS was integrated with a wireless, battery-less LC-type pressure sensor for real-time monitoring of in-stent restenosis. This wireless sensor was meticulously connected with the H-BVS framework through engineered microstructures, which not only ensured a robust bond but also significantly enhanced the overall integrity and functionality of the device. Additionally, the combination of the H-BVS and sensor was optimized to exhibit superior bending flexibility and radial strength, which are key factors in ensuring effectiveness and patient safety. The feasibility of the smart H-BVS (SH-BVS) was verified through comprehensive testing within a phantom system designed to simulate real blood flow conditions. We believe that the SH-BVS system holds strong potential to significantly improve patient monitoring and treatment strategies within the cardiovascular healthcare domain. • A Hybrid BVS with an integrated wireless pressure sensor for detecting restenosis. • Wireless pressure sensor shows remarkable signal detection capabilities. • Hybrid BVS demonstrates good bending flexibility and support performance. • Robust bonds between H-BVS and the sensor are achieved through microstructures. • The feasibility of the smart H-BVS for real-time pressure detection is verified. [ABSTRACT FROM AUTHOR]

Abstract Flexible and wearable energy harvesting devices and multifunctional sensors have been widely reported, but challenges in the large‐scale manufacturing process still exist. This work reports a large‐scale fabrication method of core‐shell triboelectric braided fibers that exhibit stable structure and strong tensile strength, which can be further integrated into power textiles with different fabric structures, such as weaving and knitting, with the purpose of biomechanical energy harvesting or plantar pressure monitoring. The triboelectric braided fibers integrating on the knitting power textiles exhibit good pressure sensitivity and fatigue resistance, which is combined with traditional socks to measure the pressure distribution of the plantar in different positions. The weaving power textiles exhibit high electrical output, which can be used for biomechanical energy harvesting and can easily light up 116 commercial LEDs. This large‐scale preparation approach provides more possibilities for power textiles applications in self‐powered wearable electronics and human–computer interfacing.

The regulation of the seasonal energy supply for natural gas and the storage of fossil energy are important to society. To achieve it, storing a large amount of natural gas in porous underground media is one of the government’s choices. Due to the successful lesson learned from the oil and gas industry, natural gas storage in underground porous media has been regarded as the most potential long−term energy storage method. In this paper, we developed a new workflow to evaluate the performance of gas reservoir−type underground natural gas storage (UGS). The theoretical background of this workflow includes the correction of the average formation pressure (AFP) and gas deviation factor by error theory and the analytical mathematical model of UGS wells. The Laplace transform, line source function, and Stehfest numerical inversion methods were used to obtain pressure solutions for typical vertical and horizontal wells in UGS. The pressure superposition principle and weighting method of the gas injection−withdrawal rate were used to obtain the AFP. Through the correction of the AFP and gas deviation factor in the material balance equation, the parameters for inventory, effective inventory (the movable gas volume at standard condition), working gas volume (the movable gas volume is operated from the upper limit pressure to the lower limit pressure), and effective gas storage volume (the available gas storage volume at reservoir condition) were determined. Numerical data from the numerical simulator was used to verify the proposed model pressure solution. Actual data from China’s largest Hutubi UGS was used to illustrate the reliability of the proposed workflow in UGS performance evaluation. The results show that large−scale gas injection and withdrawal rates lead to composite heterogeneity in gas storage wells. The nine injection and production cycles’ pressure and effective inventory changes from Hutubi UGS can be divided into a period of rapid pressure rise and a period of slow pressure increase. The final AFP is 32.8 MPa. The final inventory of the Hutubi UGS is 100.1 × 108 m3, with a capacity filling rate (the ratio of effective inventory to designed gas storage capacity) of 93.6%. The effective inventory is 95.3 × 108 m3, and the inventory utilization ratio (the ratio of effective inventory to inventory) is 95.2%. The working gas volume is 40.3 × 108 m3. This study provides a new method for inventory evaluation of the gas reservoir−type UGS.

Tracheal occlusion (TO) is a fetal treatment option for congenital diaphragmatic hernia. It aims to reduce lung hypoplasia and hypertension by occluding the trachea with a subsequent increase in pulmonary pressure. However, how TO affects lung pressure is unknown, and no devices are available for its measurement. We developed an implantable device for real-time wireless monitoring and long-term logging of lung pressure in ovine fetuses. The device comprised a microcontroller unit, two pressure sensors, an inertial measurement unit (IMU), a radio frequency unit, and an antenna. In vitro and in vivo tests were performed to evaluate device performances. A diaphragmatic hernia was created in ovine fetuses via hysterotomy. Nine devices were implanted at 100 days of gestation and remained until delivery (~142 d). One pressure sensor measured pressure in the amniotic sac and the other in the fetal trachea. In vitro pressure accuracy was median (interquartile range) 0.31% (0.1%). In vitro device lifetime was ~60 days. The in vivo device recording time was 26.0 (3.9) days and it was well tolerated by the fetus and the ewe. Data telemetry operated throughout the device lifetime. At delivery, amniotic fluid, device encapsulation, and lamb skin did not present evidence of damages. Pressure data in four lambs were analyzed. Fast pressure changes due to the spontaneous fetal activity and long-term mean pressure changes resulting from TO were detected. The IMU allowed for the assessment of changes in fetal position. This device allows long-term monitoring of mean lung pressure, spontaneous breathing activity, and movements in physiological and pathological ovine fetal models. [ABSTRACT FROM AUTHOR]

Copyright of Oil Drilling & Production Technology / Shiyou Zuancai Gongyi is the property of Shiyou Zuancai Gongyi Bianjibu and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

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Assessment of the environmental and economic performance of a safety valve requires information about the flow of the substance through the valve when it is actuated. The goal of this paper was to determine the flow rate of the discharged substance and the mass flow rate of the substance entering the safety valve when it is actuated.Proposed a mathematical model to describe the processes occurring in the valve. The model includes a system of differential equations describing the physical laws of conservation in the internal volume of the valve and differential equations, which link the value of gas flow through the valve with the pressure and the amount of movement of the shut-off disk. Used a modified method by S.K. Godunov to solve gasdynamic equations.Established that the determination of the flow and power characteristics of the valve requires the preliminary construction of a mathematical model of the safety valve operation. Based on this, proposed a method for determining the flow rate of the discharged substance and the mass rate of the substance entering the safety valve when it is actuated.Obtained the flow characteristics of the valves under review and the dynamics of movement of the shutoff disc of the valve, as well as the dependence of the pressure change on the opening time of the valve. Comparison of the calculated values with available experimental data gives good agreement of results (no more than 5.6 % for a gas flow rate, under 10 % for the movement of the valve and change the arrival of gas in time using the standard deviation function of the flow characteristics of 0.6 %), confirms the correctness of the defined mathematical model, used numerical schemes and algorithms, as well as the proposed method and recoverability of the arrival of gas in a pressure–time curve.

Background: Presence of peripheral vascular disease enhances surgical risk in cardiac surgical patients. Prior knowledge of peripheral arterial disease may help the physician make changes in the monitoring and cardiopulmonary bypass cannulation plans. It is claimed that the incidence of peripheral vascular disease in cardiac surgical patients ranges from 11 to 30%. Aims: This study was conducted to understand the characteristics of peripheral vascular disease and their implication on cardiac surgery. Settings and Design: This was a prospective study undertaken in a tertiary referral hospital. Materials and Methods: All adult patients who underwent cardiac surgery during the period of six months were included. A Doppler examination of the neck, upper limb, abdomen and lower limb was carried out by our inhouse radiologist. The incidence of peripheral vascular disease, the implication on invasive pressure monitoring site and cannulation for cardiopulmonary bypass or intraaortic balloon pump or extracorporeal membrane oxygenation were made note of. Results: During the said period, six hundred twenty eight patients underwent cardiac surgery, of whom five hundred and sixty-one patients who underwent CABG surgery. All these were subjected to Doppler examination. We observed peripheral arterial disease in 105 patients (20%). In general men suffered from PAD more often than women. Monitoring site of invasive arterial pressure, the choice of beating heart surgery, insertion of intraaortic balloon pump, femoral arterial route for cardiopulmonary bypass were some of the decision that were altered. Conclusions: Performing Doppler examination in cardiac surgical patients may yield important data that might prevent complications and support patient safety.

Optical coherence tomography (OCT) is a noninvasive 3D imaging technique that offers significant advantages over traditional microscopy and biopsy in measuring epidermal thickness (ET) when assessing skin conditions. However, OCT imagining is often required to be in a contact mode for mitigating the issues of subject movement and uneven skin topology. It is not known whether the contact would affect the ability of ET measurements. In this study, we investigate the relationship between the contact pressure applied and the ET measurements. We observed progressive deformation in the epidermis with the increase of compression forces, where a notable decrease of up to 13% in ET measurement and 70% decrease in capillary vessels was noted when imaging was in contact mode. We also observed 8.1% less deformation properties in scar tissue than in nearby healthy tissue. Our study underscored the importance of controlled pressure in contact imaging mode, which is often neglected., (© 2024 Wiley‐VCH GmbH.)

Objective: Monitoring of vessel perfusion is of high clinical importance in vascular anastomosis of free flaps. Current sensor systems are based on different principles and show limitations in validity and accuracy. Fiber optic pressure sensors exhibit high accuracy and are small in size. The aim of the present study was to evaluate the surgical feasibility of intraluminal pressure (ILP) measurements with a fiber optic pressure sensor in an animal model.Methods: In a microsurgical setting we sedated 10 Wistar rats with weight adapted phenobarbital, xylazine, and fentanyl. We performed a surgical approach to A. carotis communis and V. jugularis and introduced a 600 μm fiber optic pressure sensor into the vessels followed by measuring the ILP. The sensor was stabilized by the surrounding tissue, and the vessels were closed.Results: In all cases, surgical placement was uneventful. Measurement of intra-venous and intra-arterial pressure was possible and stable over the whole measurement period of an hour.Conclusion: Fiber optic pressure measurement in microvessels is possible and surgically feasible. An application to monitor the perfusion of free flaps seems possible.

Deformation stability plays a crucial role in the construction and operation of hydrocarbon storage salt caverns. Monitoring and analyzing wellhead pressure data under closed well conditions provide valuable insights into the evaluation of cavern stability. In this study, an analysis of five factors influencing internal brine pressure was conducted, which revealed that salt creep and brine thermal expansion contribute to an increase in internal brine pressure, while brine penetration, salt dissolution and cavern compressibility lead to a decrease. The atmospheric pressure, surface temperature, and earth tides are the other factors influencing wellhead pressure fluctuations. Through the analysis of wellhead pressure data from brine-filled salt cavern under closed conditions, the creep parameters of salt formations were calculated using the Norton-Hoff creep model. To further understand the behavior of brine-filled salt cavern, numerical simulations were conducted to analyze the brine temperature distribution and deformation stability. The volumetric average temperature of the brine exhibits a nonlinear increase over time, characterized by a rapid rise in the initial stage followed by a slower rate of change. Finally, the brine temperature stabilizes and converges toward the formation temperature. From deformation analysis, it was observed that the closed condition is more favorable for the maintenance of cavern stability in comparison to the open condition. The subsidence of the cavern roof is particularly sensitive and requires careful attention, especially for flat-roof salt caverns. Under closed conditions, it is crucial to control the brine pressure decrease rate and prevent excessively high brine pressure to ensure the mechanical and penetration stability of the brine-filled salt cavern. These findings provide valuable insights into the factors influencing internal brine pressure, the determination of creep parameters, the distribution of brine temperature, and the deformation stability of brine-filled salt caverns. [ABSTRACT FROM AUTHOR]

Sea level rise and high tide events are threatening many coastal cities, which require adequate and sustainable protection measures. The historic city centre of Venice (Italy) is often flooded during very high tide events, especially the area of St. Mark's Island, which is at the lowest elevation among all the islands forming the city. To design cost-effective protection interventions to safeguard the historical heritage, a deep understanding of flooding mechanisms and the relationship between groundwater pressure and tidal oscillations is necessary. Geotechnical survey and analyses play an important role in this process. This paper presents the results of a recent monitoring campaign carried out in St. Mark's Island. A simplified one-dimensional analytical model was derived for saturated conditions to understand the key parameters that govern tidal induced pressure oscillations in soil (material properties, geometrical features, and wave properties). Additional features, such as partially saturated soil conditions and two-dimensional effects, were investigated numerically. Results showed that significant pressure oscillations occur in the subsoil, which should not be neglected when considering the stability of horizontal architectural structures, such as the historical mosaics and paving. However, seepage flow rate is small, and thus its impact on the drainage system is limited in terms of water discharge. [ABSTRACT FROM AUTHOR]

Stroke volume is a key determinate of cardiac output. It is affected by the preload, contractility and afterload of the myocardium. It is possible to gain insight into the right and left ventricular preload following the insertion of a central venous catheter and pulmonary artery catheter to measure central venous pressure and pulmonary capillary wedge pressure, respectively. Abnormal measurements can indicate a pathophysiological state and guide management. [ABSTRACT FROM AUTHOR]

This paper presents a method for optimal pressure sensor placement in water distribution networks using information theory. The criterion for selecting the network nodes where to place the pressure sensors was that they provide the most useful information for locating leaks in the network. Considering that the node pressures measured by the sensors can be correlated (mutual information), a subset of sensor nodes in the network was chosen. The relevance of information was maximized, and information redundancy was minimized simultaneously. The selection of the nodes where to place the sensors was performed on datasets of pressure changes caused by multiple leak scenarios, which were synthetically generated by simulation using the EPANET software application. In order to select the optimal subset of nodes, the candidate nodes were ranked using a heuristic algorithm with quadratic computational cost, which made it time-efficient compared to other sensor placement algorithms. The sensor placement algorithm was implemented in MATLAB and tested on the Hanoi network. It was verified by exhaustive analysis that the selected nodes were the best combination to place the sensors and detect leaks.

In view of problems of low measurement accuracy, delayed data transmission and inconvenient equipment deployment existed in current coal seam gas pressure monitoring, a coal seam gas pressure monitoring system based on 6LoWPAN was designed. In the system, pressure measurement node selects the optimal path in 6LoWPAN network through multi-hop mode, so as to transmit gas pressure data collected in real time to border router. The border router transmits the data to ground server through industrial Ethernet, and ground equipment can query real-time monitoring data of pressure measurement node in specified area through the server. The test results show that the system can real-timely and accurately monitor coal seam gas pressure with high data communication efficiency and stability and low power consumption.

Continuous navigation information for medical insertion methods including wireless capsule endoscopy is an important feature to guide a medical instrument/object to the targeted location within a hollow organ or internal cavity of the patient in the best possible way. Also, an autonomous medical insertion or swallowable device with a self-contained navigation system would reduce the role of the high-level operator and hence reduce the human-factor mistake and risk of injury. The navigation techniques suggested for Wireless Capsule Endoscopy are image-based that are required to transfer and process a significant amount of data in real-time operation. This would increase the complexity of the system and would be more difficult in dark or liquid environments. A novel navigation system for Wireless Capsule Endoscopy/ordinary endoscopy that does not depend on any external source for operation and can handle the uncertainties of the path even in a dark or liquid environment (i.e.mucosa) of the human body is presented in this paper. The key element of the system is based on a capacitive-based pressure sensor array mounted on the capsule with the shape of semi-hemisphere. The place of each node is arranged to represent the variation in the latitude and the longitude of the travelling path. The system can acquire the required information to navigate the capsule in three-dimensional space and enhance the safety of the locomotion by monitoring the pressure between the capsule and the ambient environment. The system determines the variation of the path 180° in longitude and latitude with less than (<0.004%) percentage of error. Working algorithms for flexible and rigid environments are described in this paper. [ABSTRACT FROM AUTHOR]

Background: Presence of peripheral vascular disease enhances surgical risk in cardiac surgical patients. Prior knowledge of peripheral arterial disease may help the physician make changes in the monitoring and cardiopulmonary bypass cannulation plans. It is claimed that the incidence of peripheral vascular disease in cardiac surgical patients ranges from 11 to 30%.Aims: This study was conducted to understand the characteristics of peripheral vascular disease and their implication on cardiac surgery.Settings and Design: This was a prospective study undertaken in a tertiary referral hospital.Materials and Methods: All adult patients who underwent cardiac surgery during the period of six months were included. A Doppler examination of the neck, upper limb, abdomen and lower limb was carried out by our inhouse radiologist. The incidence of peripheral vascular disease, the implication on invasive pressure monitoring site and cannulation for cardiopulmonary bypass or intraaortic balloon pump or extracorporeal membrane oxygenation were made note of.Results: During the said period, six hundred twenty eight patients underwent cardiac surgery, of whom five hundred and sixty-one patients who underwent CABG surgery. All these were subjected to Doppler examination. We observed peripheral arterial disease in 105 patients (20%). In general men suffered from PAD more often than women. Monitoring site of invasive arterial pressure, the choice of beating heart surgery, insertion of intraaortic balloon pump, femoral arterial route for cardiopulmonary bypass were some of the decision that were altered.Conclusions: Performing Doppler examination in cardiac surgical patients may yield important data that might prevent complications and support patient safety. [ABSTRACT FROM AUTHOR]

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