搜索结果: 1-14 共查到“foF2”相关记录14条 . 查询时间(0.046 秒)
TEC and foF2 variations: preliminary results
ionospheric variability radio wave propagation space and satellite communications
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2015/9/14
Investigation of the relationship between TEC and (foF2)2 shows that although they are highly correlated, a 玥ysteresis?effect exists between them. The slab thickness is greater before than after mid-d...
Association of Total Electron Content (TEC) and foF2 variations with earthquake events at the anomaly crest region
earthquake TEC foF2 anomaly
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2015/9/14
The paper attempts to identify ionospheric parameters in association with earthquake at anomaly crest station through VHF Radio Beacon data and ground based ionosonde measurements while the Total Elec...
A single-station spectral model of the monthly median foF2 over Chongqing, China
solar cycle variation single station model geomagnetic index monthly median foF2
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2015/9/1
Hourly values of the critical frequency of the ionospheric F region, foF2, obtained at Chongqing ionospheric observatory (geographic 29.50N, 106.40E), China, during the interval of 1977 to 1997 (solar...
赤道地区电离层foF2在第23/24太阳活动周极低年期间创造了极低纪录?
极低太阳活动 赤道电离层 临界频率foF2
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2013/11/5
太阳辐射是电离层的电离源,强烈地调制电离层的变化.探索不同太阳辐射水平下的电离层状态,有助于认识电离层演变及其内在的基本物理过程.太阳活动在2008—2009年处于有记录以来的极低水平,研究电离层在此期间的变化及与其它太阳活动低年的差异是一个有益的课题.本文利用位于美洲扇区磁赤道地区Jicamarca台站(12.0°S, 283.2°E; dip 0.28°)测高仪观测的电离层F2层临界频率foF...
Day-time variations of foF2 connected to strong earthquakes
Day-time variations foF2 strong earthquakes
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2009/12/16
The statistical analysis of the characteristic frequency foF2 of the Earth's ionosphere averaged over mid-day hours – from 11:00 till 17:00 h LT – is carried out. Disturbances of foF2 connected to ear...
Day-time variations of foF2 connected to strong earthquakes
Day-time variations foF2 strong earthquakes
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2009/12/8
The statistical analysis of the characteristic frequency foF2 of the Earth's ionosphere averaged over mid-day hours – from 11:00 till 17:00 h LT – is carried out. Disturbances of foF2 connected to ear...
Neural-network-based prediction techniques for single station modeling and regional mapping of the foF2 and M(3000)F2 ionospheric characteristics
Neural-network-based prediction techniques single station modeling regional mapping ionospheric characteristics
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2009/11/12
In this work, Neural-Network-based single-station hourly daily foF2 and M(3000)F2 modelling of 15 European ionospheric stations is investigated. The data used are neural networks and hourly daily valu...
电场对暴时低纬电离层foF2变化的影响
扰动电场 电离层暴 赤道异常
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2010/8/30
电场对暴时低纬电离层foF2变化的影响。
foF2月中值太阳循环变化及单站谱模型研究
太阳循环变化 单站模型 foF2月中值 太阳黑子数
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2009/5/4
利用我国9个电离层观测站第21和22太阳周大约20年的foF2月中值数据，分析太阳活动和地磁活动对电离层foF2的影响，结果显示白天和夏季夜间foF2和太阳黑子数R之间存在着明显非线性关系，并且随着纬度的降低逐渐增强．当回归分析加入地磁Ap指数时，多重回归模型与实测值误差进一步减小，说明同时考虑太阳活动和地磁活动的非线性影响能够更好地描述foF2的变化．基于foF2太阳黑子数R及地磁指数Ap之间的...
利用人工神经网络预测电离层foF2参数
神经网络 foF2 短期预测 电离层
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2013/11/7
利用人工神经网络技术实现了电离层foF2参数提前1小时预测.从foF2时间序列本身的变化特征出发，根据时间序列相关分析结果确定网络输入参数.选用当前时刻foF2值，预测时刻前一天的foF2值，预测时刻前7天foF2平均值，当前时刻前7天foF2平均值，foF2的一阶差分及表示当前时刻t的变量共六个参数作为神经网络输入，下一时刻值作为神经网络输出.对于太阳活动高年平均预测相对误差小于6%，均方根误差...
foF2 seismo-ionospheric effect analysis:actual data and numerical simulations
foF2 seismo-ionospheric effect analysis actual data numerical simulations
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2010/1/4
On the background of seasonal and helio-geomagnetic disturbances, disturbances of the ionization density near noon connected to earthquakes are investigated. The study is performed for some tens of ea...
foF2月中值太阳循环变化及单站谱模型研究
太阳循环变化 单站模型 foF2月中值 太阳黑子数
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2008/10/10
利用我国9个电离层观测站第21和22太阳周大约20年的foF2月中值数据，分析太阳活动和地磁活动对电离层foF2的影响，结果显示白天和夏季夜间foF2和太阳黑子数R之间存在着明显非线性关系，并且随着纬度的降低逐渐增强．当回归分析加入地磁Ap指数时，多重回归模型与实测值误差进一步减小，说明同时考虑太阳活动和地磁活动的非线性影响能够更好地描述foF2的变化．基于foF2太阳黑子数R及地磁指数Ap之间的...
中国地区电离层foF2重构方法及其在短期预报中的应用
电离层重构 电离层预报 克里格法 中国参考电离层
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2008/5/20
提出了一种适合于中国地区电离层foF2的重构方法——以中国参考电离层为背景的改进克里格法.该方法把foF2的估计值与中国参考电离层模型值之差值的相对值作为区域化变量，引入电离层距离，采用克里格法实现区域电离层重构.与直接利用foF2进行克里格重构相比，以中国参考电离层为背景场保持了电离层的区域特征，提高了重构的准确性和稳定性.利用我国电离层垂测台站网的数据对该方法应用于中国地区的重构精度进行了评估...
On variations of foF2 and F-spread before strong earthquakes in Japan
variations foF2 F-spread strong earthquakes Japan
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2009/12/29
The statistical analysis of the variations of the dayly-mean frequency of the maximum ionospheric electron density foF2 is performed in connection with the occurrence of (more than 60) earthquakes wit...