The electromagnetic(EM)telemetry systems,employed for real-time data transmission from the borehole and the earth surface during drilling,are widely used in measurement-while-drilling(MWD)and logging-while-drilling(LW...The electromagnetic(EM)telemetry systems,employed for real-time data transmission from the borehole and the earth surface during drilling,are widely used in measurement-while-drilling(MWD)and logging-while-drilling(LWD).Several numerical methods,including the method of moments(MoM),the electric field integral equation(EFIE)method,and the finite-element(FE)method have been developed for the simulation of EM telemetry systems.The computational process of these methods is complicated and time-consuming.To solve this problem,we introduce an axisymmetric semi-analytical FE method(SAFEM)in the cylindrical coordinate system with the virtual layering technique for rapid simulation of EM telemetry in a layered earth.The proposed method divides the computational domain into a series of homogeneous layers.For each layer,only its cross-section is discretized,and a high-precision integration method based on Riccati equations is employed for the calculation of longitudinally homogeneous sections.The block-tridiagonal structure of the global coefficient matrix enables the use of the block Thomas algorithm,facilitating the efficient simulation of EM telemetry problems in layered media.After the theoretical development,we validate the accuracy and efficiency of our algorithm through a series of numerical experiments and comparisons with the Multiphysics modeling software COMSOL.We also discussed the impact of system parameters on EM telemetry signal and demonstrated the applicability of our method by testing it on a field dataset acquired from Dezhou,Shandong Province,China.展开更多
在不增加设备体积重量以及提高发射功率的前提下,为满足高码率遥测数据传输的需求,现有的脉冲编码调制-频调(Pulse Code Modulation Frequency Modulation, PCM-FM)遥测系统广泛使用多符号检测(Multiple Symbol Detection, MSD)算法和Tu...在不增加设备体积重量以及提高发射功率的前提下,为满足高码率遥测数据传输的需求,现有的脉冲编码调制-频调(Pulse Code Modulation Frequency Modulation, PCM-FM)遥测系统广泛使用多符号检测(Multiple Symbol Detection, MSD)算法和Turbo乘积码(TPC)技术。调制指数是PCM-FM遥测系统中的重要参数之一,对系统带宽和误码率有重要影响。本文分析了MSD多符号检测算法原理,通过计算互相关系数及Matlab仿真,分析了调制指数大小对带宽和误码率的影响,指出将调制指数设置为0.715较为合适;分析了调制指数偏差对信噪比损耗的影响,利用MSD算法的相位网格图分析了调制指数偏差对误码和码同步的影响,指出随机数据比连“0”或连“1”数据具有更好的容忍能力。展开更多
This article introduces a cable-free real-time telemetry seismic acquisition system(hereinafter referred to as the cable-free real-time telemetry system)that utilizes 4G/5G technology.This system facilitates the real-...This article introduces a cable-free real-time telemetry seismic acquisition system(hereinafter referred to as the cable-free real-time telemetry system)that utilizes 4G/5G technology.This system facilitates the real-time acquisition and quality control of seismic data,the real-time monitoring of equipment location and health status,the synchronous transmission of collected data between the cloud and client,and the real-time issuance of operational instructions.It addresses the critical limitation of existing seismic node equipment,which is often restricted to mining and blind storage due to the absence of a wired or wireless communication link between the acquisition node device and the central control unit.This limitation necessitates local data storage and rendering real-time quality control unfeasible.Typically,quality control is conducted post-task completion,requiring the overall retrieval and downloading of data.If data issues are identifi ed,it becomes necessary to eliminate faulty tracks and determine the need for supplementary acquisition,which can lead to delays in the acquisition process.The implementation of real-time monitoring and early warning systems for equipment health status aims to mitigate the risk of poor data quality resulting from equipment anomalies.Furthermore,the real-time synchronous transmission between the cloud and server addresses the bottleneck of slow download speeds associated with the centralized retrieval of data from multiple node devices during blind acquisition and storage.A real-time microseismic data acquisition test and verifi cation were conducted at a fracturing site in an eastern oil and gas fi eld.Analysis of the test data indicates that the overall performance indicators of the system are comparable to those of existing mainstream system equipment,demonstrating stability and reliability.The performance parameters fully satisfy the technical requirements for oilfield fracturing monitoring scenarios,suggesting promising prospects for further promotion and application.展开更多
A high precision, high antijamming multipoint infrared telemetry system was developed to measure the piston temperature in internal combustion engine. The temperature at the measuring point is converted into correspon...A high precision, high antijamming multipoint infrared telemetry system was developed to measure the piston temperature in internal combustion engine. The temperature at the measuring point is converted into corresponding voltage signal by the thermo-couple first. Then after the V/F stage, the voltage signal is converted into the frequency signal to drive the infrared light-emitting diode to transmit infrared pulses. At the receiver end, a photosensitive audion receives the infrared pulses. After conversion, the voltage recorded by the receiver stands for the magnitude of temperature at the measuring point. Test results of the system indicate that the system is practical and the system can perform multipoint looping temperature measurements for the piston.展开更多
A programmable high-accuracy system was proposed to collect and process telemetric fast varying signals,which consists of pre-circuit,analog-to-digital（A/D）conversion unit and signal collection and processing part.P...A programmable high-accuracy system was proposed to collect and process telemetric fast varying signals,which consists of pre-circuit,analog-to-digital（A/D）conversion unit and signal collection and processing part.Performance analysis demonstrates that this novel telemetry-acquisition method is a potential solution to rapidly process fast varying signals and efficiently utilize telemetry channel.展开更多
Objective:To investigate the spatial gradient of intraoperative impedance across the cochlear electrode array in pediatric cochlear implant recipients and assess its potential as a physiological indicator for the elec...Objective:To investigate the spatial gradient of intraoperative impedance across the cochlear electrode array in pediatric cochlear implant recipients and assess its potential as a physiological indicator for the electrode-neural interface.Methods:A prospective observational study involving 56 pediatric patients underwent cochlear implantation with Cochlear Nucleus devices.Intraoperative polarized impedance and electrically evoked compound action potential(ECAP)threshold were recorded across all 1232 electrodes using AutoNRT software.Eight electrodes with open-or short-circuit were excluded,leaving 1,224 for analysis.Impedance values were categorized by cochlear region(basal,middle,apical),and electrodes with elevated impedance(10-20 kΩ)were analyzed for regional distribution and clinical relevance.Data were analyzed for spatial patterns and correlation with the ECAP threshold profiles.Results:A consistent basal-to-apical increase in impedance was observed(7.7±1.9,9.2±1.4,10.8±1.5 kΩ;p<0.001).Impedance and ECAP threshold were weakly correlated(ρ=-0.20,p<0.001;β=-1.26,p<0.001),with a positive association in the apical region(ρ=0.12,p=0.048).Electrodes with higher impedance(1020 kΩ)were less likely to show elevated or absent TNRT(OR=0.175,p=0.02).The impedance gradient persisted across age groups and was significantly correlated with ECAP threshold patterns.Conclusion:Intraoperative impedance monitoring reveals a strong and physiologically consistent gradient,with higher values in apical electrodes.This gradient reflects anatomical and tissue interface variations,which may offer a valuable physiological indicator for intraoperative electrode positioning and neural interface integrity.展开更多
Unmanned aerial vehicles(UAVs),especially quadcopters,have become indispensable in numerous industrial and scientific applications due to their flexibility,lowcost,and capability to operate in dynamic environments.Thi...Unmanned aerial vehicles(UAVs),especially quadcopters,have become indispensable in numerous industrial and scientific applications due to their flexibility,lowcost,and capability to operate in dynamic environments.This paper presents a complete design and implementation of a compact autonomous quadcopter capable of trajectory tracking,object detection,precision landing,and real-time telemetry via long-range communication protocols.The system integrates an onboard flight controller running real-time sensor fusion algorithms,a vision-based detection system on a companion single-board computer,and a telemetry unit using Long Range(LoRa)communication.Extensive flight tests were conducted to validate the system’s stability,communication range,and autonomous capabilities.Potential applications in law enforcement,agriculture,search and rescue,and environmental monitoring are also discussed.展开更多
基金supported by the Major Research Project on Scientific Instrument Development of the National Natural Science Foundation of China(42327901)National Natural Science Foundation of China(42030806,42074120,41904104,423B2405).
文摘The electromagnetic(EM)telemetry systems,employed for real-time data transmission from the borehole and the earth surface during drilling,are widely used in measurement-while-drilling(MWD)and logging-while-drilling(LWD).Several numerical methods,including the method of moments(MoM),the electric field integral equation(EFIE)method,and the finite-element(FE)method have been developed for the simulation of EM telemetry systems.The computational process of these methods is complicated and time-consuming.To solve this problem,we introduce an axisymmetric semi-analytical FE method(SAFEM)in the cylindrical coordinate system with the virtual layering technique for rapid simulation of EM telemetry in a layered earth.The proposed method divides the computational domain into a series of homogeneous layers.For each layer,only its cross-section is discretized,and a high-precision integration method based on Riccati equations is employed for the calculation of longitudinally homogeneous sections.The block-tridiagonal structure of the global coefficient matrix enables the use of the block Thomas algorithm,facilitating the efficient simulation of EM telemetry problems in layered media.After the theoretical development,we validate the accuracy and efficiency of our algorithm through a series of numerical experiments and comparisons with the Multiphysics modeling software COMSOL.We also discussed the impact of system parameters on EM telemetry signal and demonstrated the applicability of our method by testing it on a field dataset acquired from Dezhou,Shandong Province,China.
文摘在不增加设备体积重量以及提高发射功率的前提下,为满足高码率遥测数据传输的需求,现有的脉冲编码调制-频调(Pulse Code Modulation Frequency Modulation, PCM-FM)遥测系统广泛使用多符号检测(Multiple Symbol Detection, MSD)算法和Turbo乘积码(TPC)技术。调制指数是PCM-FM遥测系统中的重要参数之一,对系统带宽和误码率有重要影响。本文分析了MSD多符号检测算法原理,通过计算互相关系数及Matlab仿真,分析了调制指数大小对带宽和误码率的影响,指出将调制指数设置为0.715较为合适;分析了调制指数偏差对信噪比损耗的影响,利用MSD算法的相位网格图分析了调制指数偏差对误码和码同步的影响,指出随机数据比连“0”或连“1”数据具有更好的容忍能力。
基金funded by the National Natural Science Foundation of China (42074127)the Key Program of National Natural Science Foundation of China (41930425)Research on Key Technologies for the Production, Exploration, and Development of Continental Shale Oil (2023ZZ15YJ02)。
文摘This article introduces a cable-free real-time telemetry seismic acquisition system(hereinafter referred to as the cable-free real-time telemetry system)that utilizes 4G/5G technology.This system facilitates the real-time acquisition and quality control of seismic data,the real-time monitoring of equipment location and health status,the synchronous transmission of collected data between the cloud and client,and the real-time issuance of operational instructions.It addresses the critical limitation of existing seismic node equipment,which is often restricted to mining and blind storage due to the absence of a wired or wireless communication link between the acquisition node device and the central control unit.This limitation necessitates local data storage and rendering real-time quality control unfeasible.Typically,quality control is conducted post-task completion,requiring the overall retrieval and downloading of data.If data issues are identifi ed,it becomes necessary to eliminate faulty tracks and determine the need for supplementary acquisition,which can lead to delays in the acquisition process.The implementation of real-time monitoring and early warning systems for equipment health status aims to mitigate the risk of poor data quality resulting from equipment anomalies.Furthermore,the real-time synchronous transmission between the cloud and server addresses the bottleneck of slow download speeds associated with the centralized retrieval of data from multiple node devices during blind acquisition and storage.A real-time microseismic data acquisition test and verifi cation were conducted at a fracturing site in an eastern oil and gas fi eld.Analysis of the test data indicates that the overall performance indicators of the system are comparable to those of existing mainstream system equipment,demonstrating stability and reliability.The performance parameters fully satisfy the technical requirements for oilfield fracturing monitoring scenarios,suggesting promising prospects for further promotion and application.
文摘A high precision, high antijamming multipoint infrared telemetry system was developed to measure the piston temperature in internal combustion engine. The temperature at the measuring point is converted into corresponding voltage signal by the thermo-couple first. Then after the V/F stage, the voltage signal is converted into the frequency signal to drive the infrared light-emitting diode to transmit infrared pulses. At the receiver end, a photosensitive audion receives the infrared pulses. After conversion, the voltage recorded by the receiver stands for the magnitude of temperature at the measuring point. Test results of the system indicate that the system is practical and the system can perform multipoint looping temperature measurements for the piston.
文摘A programmable high-accuracy system was proposed to collect and process telemetric fast varying signals,which consists of pre-circuit,analog-to-digital（A/D）conversion unit and signal collection and processing part.Performance analysis demonstrates that this novel telemetry-acquisition method is a potential solution to rapidly process fast varying signals and efficiently utilize telemetry channel.
文摘Objective:To investigate the spatial gradient of intraoperative impedance across the cochlear electrode array in pediatric cochlear implant recipients and assess its potential as a physiological indicator for the electrode-neural interface.Methods:A prospective observational study involving 56 pediatric patients underwent cochlear implantation with Cochlear Nucleus devices.Intraoperative polarized impedance and electrically evoked compound action potential(ECAP)threshold were recorded across all 1232 electrodes using AutoNRT software.Eight electrodes with open-or short-circuit were excluded,leaving 1,224 for analysis.Impedance values were categorized by cochlear region(basal,middle,apical),and electrodes with elevated impedance(10-20 kΩ)were analyzed for regional distribution and clinical relevance.Data were analyzed for spatial patterns and correlation with the ECAP threshold profiles.Results:A consistent basal-to-apical increase in impedance was observed(7.7±1.9,9.2±1.4,10.8±1.5 kΩ;p<0.001).Impedance and ECAP threshold were weakly correlated(ρ=-0.20,p<0.001;β=-1.26,p<0.001),with a positive association in the apical region(ρ=0.12,p=0.048).Electrodes with higher impedance(1020 kΩ)were less likely to show elevated or absent TNRT(OR=0.175,p=0.02).The impedance gradient persisted across age groups and was significantly correlated with ECAP threshold patterns.Conclusion:Intraoperative impedance monitoring reveals a strong and physiologically consistent gradient,with higher values in apical electrodes.This gradient reflects anatomical and tissue interface variations,which may offer a valuable physiological indicator for intraoperative electrode positioning and neural interface integrity.
文摘Unmanned aerial vehicles(UAVs),especially quadcopters,have become indispensable in numerous industrial and scientific applications due to their flexibility,lowcost,and capability to operate in dynamic environments.This paper presents a complete design and implementation of a compact autonomous quadcopter capable of trajectory tracking,object detection,precision landing,and real-time telemetry via long-range communication protocols.The system integrates an onboard flight controller running real-time sensor fusion algorithms,a vision-based detection system on a companion single-board computer,and a telemetry unit using Long Range(LoRa)communication.Extensive flight tests were conducted to validate the system’s stability,communication range,and autonomous capabilities.Potential applications in law enforcement,agriculture,search and rescue,and environmental monitoring are also discussed.
