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Effect of autaptic delay signal on spike-timing precision of single neuron
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作者 马璇 赵鸭鸭 +2 位作者 王亚峰 陈月玲 王恒通 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第3期613-620,共8页
Experimental and theoretical studies have reported that the precise firing of neurons is crucial for sensory representation.Autapse serves as a special synapse connecting neuron and itself,which has also been found to... Experimental and theoretical studies have reported that the precise firing of neurons is crucial for sensory representation.Autapse serves as a special synapse connecting neuron and itself,which has also been found to improve the accuracy of neuronal response.In current work,the effect of autaptic delay signal on the spike-timing precision is investigated on a single autaptic Hodgkin–Huxley neuron in the present of noise.The simulation results show that both excitatory and inhibitory autaptic signals can effectively adjust the precise spike time of neurons with noise by choosing the appropriate coupling strength g and time delay of autaptic signalτ.The g–τparameter space is divided into two regions:one is the region where the spike-timing precision is effectively regulated;the other is the region where the neuronal firing is almost not regulated.For the excitatory and inhibitory autapse,the range of parameters causing the accuracy of neuronal firing is different.Moreover,it is also found that the mechanisms of the spike-timing precision regulation are different for the two kinds of autaptic signals. 展开更多
关键词 autapse time delay spike-timing precision
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New research trends on high-precision time transfer technology 被引量:5
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作者 DONG Ruifang QUAN Run'ai +6 位作者 HOU Feiyan WANG Shaofeng XIANG Xiao ZHOU Conghua WANG Mengmeng LIU Tao ZHANG Shou'gang 《Instrumentation》 2015年第4期3-15,共13页
High-precision time transfer plays an important role in the areas of fundamental research and applications. Accompanying w ith the remarkable improvements in the ability of generating and measuring high-accuracy time-... High-precision time transfer plays an important role in the areas of fundamental research and applications. Accompanying w ith the remarkable improvements in the ability of generating and measuring high-accuracy time-frequency signal,seeking for new time-transfer techniques betw een distant clocks w ith much further improved accuracy attracts attentions w orld-w idely. The time-transfer technique based on optical pulses has the highest precision presently,and the further improvement in the accuracy is heavily dependent on the time-domain properties of the pulse as w ell as the sensitivity of the applied measurement on the exchanged pulse. The application of optical frequency comb in time transfer for a precision up to femtosecond level are currently the focus of much interest,and has recently achieved many breakthroughs. Further investigations show that,utilizing quantum techniques,i.e. quantum measurement technique and quantum optical pulse source,can lead to a new limit on the measured timing information. Furthermore,it can be immune from atmospheric parameters,such as pressure,temperature,humidity and so on.Such quantum improvements on time-transfer have a bright prospect in the future applications requiring extremely high-accuracy timing and ranging. The potential achievements w ill form a technical basis for the future realization of sub-femtosecond time transfer system. 展开更多
关键词 high-precision time TRANSFER QUANTUM improvement PULSE SHAPING QUANTUM frequency COMB
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A High-Precision Time Handling Library
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作者 Irina Fedotova Eduard Siemens Hao Hu 《通讯和计算机(中英文版)》 2013年第8期1076-1086,共11页
关键词 时间处理 高精度 网络性能 时间计数器 Linux 计算机资源 时间控制 测量程序
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TIME-SPACE CONCEPT FOR PRECISION MEASUREMENT 被引量:4
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作者 LIU Xiaokang PENG Donglin ZHU Ge WANG Xianquan 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2008年第3期112-115,共4页
The transformation between time and space is discussed. To improve real-time response speed of intelligent measuring system, the concept of exchanging program execution time with more circuitry is presented working in... The transformation between time and space is discussed. To improve real-time response speed of intelligent measuring system, the concept of exchanging program execution time with more circuitry is presented working in cycle mode. Displacement measuring by magnification is achieved with period measurement by magnification. To change the condition that traditional precision measurement depends on machining precision greatly, the concept of measuring space with time and theory of time-space coordinate transformation are proposed. Guided by the idea of measuring space with time, differential frequency measurement system and time grating displacement sensor are developed based on the proposed novel methods. And high-precision measurement is achieved without high-precision manufacture, which embeds the remarkable characteristics of low cost but high precision to the devices. Experiment and test results conform the validity of the proposed time-space concept. 展开更多
关键词 Time-space precision measurement Control flow Differential frequency Time grating
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Constructions and Applied Examinations of a Kind of Square-Conservative Schemes in High Precision in the Time Direction 被引量:1
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作者 季仲贞 王斌 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 1993年第3期315-324,共10页
In order to meet the needs of work in numerical weather forecast and in numerical simulations for climate change and ocean current, a kind of difference scheme in high precision in the time direction developed from th... In order to meet the needs of work in numerical weather forecast and in numerical simulations for climate change and ocean current, a kind of difference scheme in high precision in the time direction developed from the completely square-conservative difference scheme in explicit way is built by means of the Taylor expansion. A numerical test with 4-wave Rossby-Haurwitz waves on them and an application of them on the monthly mean current the of South China Sea are carried out, from which, it is found that not only do the new schemes have high harmony and approximate precision but also can the time step of the schemes be lengthened and can much computational time be saved. Therefore, they are worth generalizing and applying. 展开更多
关键词 Completely square-conservative Explicit scheme High precision in the time direction Harmonious dissipative operator
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The Real-Time,High Precision Phase Difference Measurement of Electron Density in HL-2A Tokamak 被引量:1
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作者 丁宝钢 吴彤宇 +2 位作者 李世平 周艳 阴泽杰 《Plasma Science and Technology》 SCIE EI CAS CSCD 2015年第9期797-801,共5页
This paper introduces a real-time high precision measurement of phase difference based on Field Programmable Gate Array(FPGA) technology,which has been successfully applied to laser grating interference measurement ... This paper introduces a real-time high precision measurement of phase difference based on Field Programmable Gate Array(FPGA) technology,which has been successfully applied to laser grating interference measurement and real-time feedback of plasma electron density in HL-2A tokamak.It can track the changes of electron density while setting the starting point of the density curve to zero.In a laboratory test,the measuring accuracy of phase difference is less than 0.1°,the time resolution is 80 ns,and the feedback delay is 180 μs. 展开更多
关键词 phase difference HL-2A FPGA REAL-TIME high precision
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The spike timing precision of FitzHugh-Nagumo neuron network coupled by gap junctions
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作者 张素花 展永 +2 位作者 于慧 安海龙 赵同军 《Chinese Physics B》 SCIE EI CAS CSCD 2006年第10期2450-2457,共8页
It has been proved recently that the spike timing can play an important role in information transmission, so in this paper we develop a network with N-unlt FitzHugh-Nagumo neurons coupled by gap junctions and discuss ... It has been proved recently that the spike timing can play an important role in information transmission, so in this paper we develop a network with N-unlt FitzHugh-Nagumo neurons coupled by gap junctions and discuss the dependence of the spike timing precision on synaptic coupling strength, the noise intensity and the size of the neuron ensemble. The calculated results show that the spike timing precision decreases as the noise intensity increases; and the ensemble spike timing precision increases with coupling strength increasing. The electric synapse coupling has a more important effect on the spike timing precision than the chemical synapse coupling. 展开更多
关键词 spike timing precision gap junction FitzHugh-Nagumo model
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Application of Monte Carlo method in rudder control precision 被引量:2
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作者 凡永磊 陈国光 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2015年第4期378-383,共6页
After the trajectory simulation model of rudder control rocket with six degrees of freedom is established by Matlab/ Simulink, the simulated targeting of rudder control rocket with rudder angle error and starting cont... After the trajectory simulation model of rudder control rocket with six degrees of freedom is established by Matlab/ Simulink, the simulated targeting of rudder control rocket with rudder angle error and starting control moment error is carried out respectively by means of Monte Carlo method and the distribution of impact points of rudder control rocket is counted from all the successful subsamples. In the case of adding interference errors associated with rudder angle error and starting time error, the simulation analysis of impact point dispersion is done and its lateral and longitudinal correction abilities at different targeting angles are simulated to identify the effects of these factors on characteristics and control precision of the rudder control rocket, which provides the relevant reference for high-precision design of rudder control system. 展开更多
关键词 rudder control precision rudder angle error starting control time error Monte Carlo method
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Effect and satisfaction of outpatient services by precision valuation reservation registration 被引量:2
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作者 Hai-Jun Jin An-Lan Cheng +2 位作者 Jin-Yan Qian Li-Mei Lin Huan-Mei Tang 《World Journal of Clinical Cases》 SCIE 2021年第26期7750-7761,共12页
BACKGROUND Due to improvements in living standards,people are now paying more attention to their health.In China,more patients choose to go to large or well-known hospitals,which leads to constant crowding of outpatie... BACKGROUND Due to improvements in living standards,people are now paying more attention to their health.In China,more patients choose to go to large or well-known hospitals,which leads to constant crowding of outpatient clinics in these hospitals.AIM To establish precision valuation reservation registration aimed at shortening waiting time,improving patient experience and promoting the satisfaction of outpatients and medical staff.METHODS On the basis of the implementation of a conventional appointment system,more reasonable time intervals were set for different doctors by evaluating the actual capacity of each doctor to receive patients,and appointment times were made more accurate through intervention.The change in consultation waiting time of patients was then compared.Correlations between the consultation waiting time of patients and the satisfaction of patients or satisfaction of medical staff were analyzed.RESULTS After precision valuation reservation registration,the average consultation waiting time of patients reduced from 18.47 min to 10.11 min(t=8.90,P<0.001).The satisfaction score of patients increased from 91.33 to 96.27(t=-8.62,P<0.001),and the satisfaction score of medical staff increased from 90.51 to 96.04(t=-10.50,P<0.001).The consultation waiting time of patients was negatively correlated with their satisfaction scores(γ=-0.89,P<0.001).The consultation waiting time of patients was also negatively correlated with medical staff satisfaction scores(γ=-0.96,P<0.001).CONCLUSION Precision valuation reservation registration significantly shortened outpatient waiting times and improve the satisfaction of not only patients but also medical staff.This approach played an important role in improving outpatient services,provided a model that is supported by relevant evidence and could continuously improve the quality of management.Precision valuation reservation registration is worth promoting and applying in the clinic. 展开更多
关键词 precision valuation reservation Shorten waiting time Effect on outpatient service SATISFACTION OUTPATIENTS Medical staff
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TIME PRECISE INTEGRATION METHOD FOR CONSTRAINED NONLINEAR CONTROL SYSTEM
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作者 邓子辰 钟万勰 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2002年第1期18-25,共8页
For the constrained nonlinear optimal control problem, by taking the first term of Taylor series, the dynamic equation is linearized. Thus by, introducing into the dual variable (Lagrange multiplier vector), the dynam... For the constrained nonlinear optimal control problem, by taking the first term of Taylor series, the dynamic equation is linearized. Thus by, introducing into the dual variable (Lagrange multiplier vector), the dynamic equation can be transformed into Hamilton system from Lagrange system on the basis of the original variable. Under the whole state, the problem discussed can be described from a new view, and the equation can be precisely solved by, the time precise integration method established in linear dynamic system. A numerical example shows the effectiveness of the method. 展开更多
关键词 nonlinear control system constraint equation time precise integration
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NONEL High Precision MS Delay Detonator
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作者 Daze Lin, Peng Yang Civil and Environmental Engineering School, University of Science and Technology Beijing, Beijing 100083, China 《Journal of University of Science and Technology Beijing》 CSCD 2001年第3期164-166,共3页
The NONEL high precision MS Delay Detonator (FDG-1detonator) is introduced. The main aspects about the FDG-1 detonator include the choice of structure, delay composition, control of the gas chamber, optimum charge and... The NONEL high precision MS Delay Detonator (FDG-1detonator) is introduced. The main aspects about the FDG-1 detonator include the choice of structure, delay composition, control of the gas chamber, optimum charge and density, suitable explosives per meter in the NONEL tube, base firing charge and the main specifications. The improvement of the characteristics of FDG-1 detonator has been tested systematically. The testing method is reliable and its precision can meet the demand for usage. 展开更多
关键词 NONEL high precision MS Delay Detonator delay time
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MEASURING PRECISION OF INDUCED POLARIZATION METHOD
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作者 He,Jishan(Central South University of Technology,Changsha 410083) 《中国有色金属学会会刊:英文版》 CSCD 1994年第4期1-6,共6页
MEASURINGPRECISIONOFINDUCEDPOLARIZATIONMETHOD¥He,Jishan(CentralSouthUniversityofTechnology,Changsha410083)Ab... MEASURINGPRECISIONOFINDUCEDPOLARIZATIONMETHOD¥He,Jishan(CentralSouthUniversityofTechnology,Changsha410083)Abstract:Onthepremi... 展开更多
关键词 MEASURING precision induced POLARIZATION method (IP) DUAL-FREQUENCY IP frequency DOMAIN IP time IP
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Improvement of System Dynamic Precision by Dynamic Prediction
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作者 HU Chun -hai (Yanshan University, Qinhuangdao 066004,CHN) 《Semiconductor Photonics and Technology》 CAS 2000年第1期34-36,58,共4页
According to the characteristic of the sensor inertia, the dynamic prediction to improve the system dynamic precision is presented in this paper. With the recurrence calculation of time constant of the sensor, the sys... According to the characteristic of the sensor inertia, the dynamic prediction to improve the system dynamic precision is presented in this paper. With the recurrence calculation of time constant of the sensor, the system dynamic precision is greatly improved. The example using this method is given. 展开更多
关键词 INERTIA Dynamic prediction Time constant Dynamic precision
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精细积分方法的发展与扩展应用 被引量:1
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作者 姚伟岸 高强 +1 位作者 谭述君 吴锋 《计算力学学报》 CAS CSCD 北大核心 2024年第1期2-25,共24页
钟万勰院士于1991年首先提出计算矩阵指数的精细积分方法,其要点是2N类算法和增量存储。精细积分方法可给出矩阵指数在计算机意义上的精确解,为常微分方程的数值计算提供了高精度、高稳定性的算法,现已成功应用于结构动力响应、随机振... 钟万勰院士于1991年首先提出计算矩阵指数的精细积分方法,其要点是2N类算法和增量存储。精细积分方法可给出矩阵指数在计算机意义上的精确解,为常微分方程的数值计算提供了高精度、高稳定性的算法,现已成功应用于结构动力响应、随机振动、热传导以及最优控制等众多领域。本文首先介绍矩阵指数精细积分方法的提出、基本思想和发展;然后依次介绍在时不变/时变线性微分方程、非线性微分方程以及大规模问题求解中发展起来的各种精细积分方法,分析了其优缺点和适用范围;最后介绍了精细积分方法的基本思想在两点边值问题、椭圆函数和病态代数方程等问题的扩展应用,进一步展示了该思想的特色。 展开更多
关键词 精细积分方法 矩阵指数 常微分方程 时程积分
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基于ARIMA-TCN混合模型的高速铁路时间同步方法
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作者 陈永 詹芝贤 张薇 《铁道学报》 EI CAS CSCD 北大核心 2024年第6期90-100,共11页
列控系统作为高速铁路的核心系统,保持其系统的时间同步对于行车安全至关重要。针对现有时间同步方法易受时变上下行传输时延、随机时钟跳变等影响,导致主从时钟偏移估计不准确的问题,提出一种基于差分自回归移动平均-时域卷积神经网络(... 列控系统作为高速铁路的核心系统,保持其系统的时间同步对于行车安全至关重要。针对现有时间同步方法易受时变上下行传输时延、随机时钟跳变等影响,导致主从时钟偏移估计不准确的问题,提出一种基于差分自回归移动平均-时域卷积神经网络(ARIMA-TCN)混合模型的高速铁路时间同步方法。首先,根据上下行链路传输速率的不对称比,建立高速铁路时钟的数学理论和实际观测模型。然后,使用拉依达准则识别处理跳变异常值,完成实际时间序列的预处理。再次,使用ARIMA模型平滑时间序列中不确定时延带来的噪声抖动,获得平稳的时间序列。最后,通过提出的注意力增强TCN模型进行预测补偿,完成时钟偏移的补偿校正。通过实验仿真,得到基站区间内位置、基站间距以及车速对高速铁路时间同步的影响性分析。实验结果表明:与对比方法相比,所提方法补偿后的均方根误差较最小二乘法减少了75%、较最大似然估计方法误差减少了44.4%,较BP神经网络方法误差减少了16.7%,验证所提方法具有更低的同步误差和更高的同步精度。 展开更多
关键词 时间同步 精确时钟协议 差分自回归移动平均模型 注意力增强时域卷积网络 时间补偿
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实时PPP离岸潮位遥测方法与试验
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作者 刘亮 《海洋测绘》 CSCD 北大核心 2024年第2期18-21,共4页
为降低离岸潮位实时遥测成本,提高适用性,提出了基于实时精密单点定位的离岸潮位数据获取与提取方法,利用小型浮标搭载具有实时PPP和远程通讯功能的GNSS接收机进行离岸潮位遥测,原始观测数据经粗差剔除、均值化处理、S-G滤波后,较好地... 为降低离岸潮位实时遥测成本,提高适用性,提出了基于实时精密单点定位的离岸潮位数据获取与提取方法,利用小型浮标搭载具有实时PPP和远程通讯功能的GNSS接收机进行离岸潮位遥测,原始观测数据经粗差剔除、均值化处理、S-G滤波后,较好地剔除了风、浪、流等引起浮标姿态变化所带来的测量误差。研发了相应软硬件,并在天津港外海进行了试验,测试结果优于±8cm,整体中误差为±3.7cm,满足海洋观测规范要求。相较基于压力式传感器加声学通信的现行数据采集方式,该方法具有建设成本较低、观测方式简单、后期维护方便、产业化前景好等特点,可进一步在实际项目中推广使用。 展开更多
关键词 海洋测绘 潮位遥测 实时精密单点定位 实时数据流 S-C滤波
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中厚板边部裂纹的原因及措施
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作者 吴红广 杨杰 +1 位作者 贺瑞飞 李辉 《河南冶金》 2024年第1期44-48,共5页
板坯连铸机设备改造后钢板边部裂纹发生率异常增高,对钢板裂纹微观形貌进行分析得出:钢板边部裂纹来源于连铸坯。对连铸坯表面宏观形貌、保护渣、钢水成分、结晶器冷却、连铸设备维护以及结晶器振动参数等因素进行了对比与分析,结果表明... 板坯连铸机设备改造后钢板边部裂纹发生率异常增高,对钢板裂纹微观形貌进行分析得出:钢板边部裂纹来源于连铸坯。对连铸坯表面宏观形貌、保护渣、钢水成分、结晶器冷却、连铸设备维护以及结晶器振动参数等因素进行了对比与分析,结果表明:连铸坯四个角振痕不均匀、不规则、有时错乱且分布不规律,结晶器振动参数不合理、连铸机工况不佳是钢板边部裂纹产生的主要原因。通过调整结晶器振动起始位置到中位、延长结晶器振幅变化的斜坡时间、提高连铸机工况条件等,使钢板边部裂纹发生率由5%~50%降低至1%以内。 展开更多
关键词 边部裂纹 振痕 结晶器振动 设备精度 中位 斜坡时间
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基于有限时间扩张状态观测器的水下机器人精准跟踪控制系统设计
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作者 王坤 《计算机测量与控制》 2024年第9期149-156,共8页
水下机器人在运动过程中极易受到水环境因素的干扰发生运动偏移,为了保证水下机器人的精准、稳定航行,利用有限时间扩张状态观测器优化设计水下机器人精准跟踪控制系统;设计有限时间扩张状态观测器、水下机器人传感器、跟踪控制器和推进... 水下机器人在运动过程中极易受到水环境因素的干扰发生运动偏移,为了保证水下机器人的精准、稳定航行,利用有限时间扩张状态观测器优化设计水下机器人精准跟踪控制系统;设计有限时间扩张状态观测器、水下机器人传感器、跟踪控制器和推进器,强化硬件系统的密封防水设计强度,完成系统硬件设计;根据水下航行任务,规划机器人的航行轨迹,作为系统控制目标;求解机器人位置、姿态角、速度等运动参数,得出水下机器人的跟踪结果;利用有限时间扩张状态观测器检测航行环境参数,结合当前机器人状态的跟踪结果,计算机器人运动控制量,在硬件系统的支持下,完成系统的精准跟踪控制功能;[JP2]通过系统测试实验得出结论,静力水环境场景下水下机器人的平均位置跟踪误差为14 m、平均角度控制误差为0.10°,航行速度控制误差为0.5 m/s;动力水环境场景下水下机器人的位置跟踪误差最大值为9 m、平均角度控制误差为0.10°、航行速度控制误差为0.5 m/s。 展开更多
关键词 有限时间扩张状态观测器 水下机器人 精准跟踪 机器人控制系统
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精密播种机实时监测系统的设计
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作者 郭玮 牛彦明 宋海燕 《农业技术与装备》 2024年第7期19-21,24,共4页
精密播种机作业时多处于封闭状态,出现的漏播、重播等问题仅凭人的视听难以及时发现,对精密播种机播种过程进行实时监测具有重要意义。采用STM32F103单片机作为主控芯片,利用光电传感器作为检测元件,设计了一种精密播种机实时监测系统... 精密播种机作业时多处于封闭状态,出现的漏播、重播等问题仅凭人的视听难以及时发现,对精密播种机播种过程进行实时监测具有重要意义。采用STM32F103单片机作为主控芯片,利用光电传感器作为检测元件,设计了一种精密播种机实时监测系统。试验结果表明,该监测装置播种监测精度可达到92%以上,可满足实际播种监测的需要,提高了精密播种机的播种效率。 展开更多
关键词 精密播种机 实时监测 单片机 传感器
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Galileo高精度定位服务初始服务性能评估 被引量:1
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作者 季锐 刘长建 +2 位作者 王敏 孙爽 孟欣 《大地测量与地球动力学》 CSCD 北大核心 2024年第1期21-26,共6页
从服务改正数可用性、轨道钟差精度等方面综合分析高精度定位服务(high accuracy service,HAS)的性能,同时利用全球各区域的多模GNSS实验跟踪网(multi-GNSS experiment,MGEX)测站分析HAS PPP的性能。结果表明,大部分卫星改正数的可用性... 从服务改正数可用性、轨道钟差精度等方面综合分析高精度定位服务(high accuracy service,HAS)的性能,同时利用全球各区域的多模GNSS实验跟踪网(multi-GNSS experiment,MGEX)测站分析HAS PPP的性能。结果表明,大部分卫星改正数的可用性在80%以上;GPS和Galileo的空间信号测距误差(signal-in-space ranging error,SISRE)分别为0.163 m、0.097 m;MGEX测站水平方向定位精度均小于0.2 m,垂直方向均小于0.4 m。 展开更多
关键词 HAS 改正数精度 定位性能 实时精密单点定位
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