scholarly journals Automatic estimation of dynamics of ionospheric disturbances with 1–15 minute lifetimes as derived from ISTP SB RAS fast chirp ionosonde data

2018 ◽  
pp. 64-70
Author(s):  
Олег Бернгардт ◽  
Oleg Berngardt ◽  
Татьяна Бубнова ◽  
Tatyana Bubnova ◽  
Алексей Подлесный ◽  
...  
Keyword(s):  
Experimental Data ◽  
High Repetition Rate ◽  
Ionospheric Disturbances ◽  
Characteristic Parameters ◽  
Effective Height ◽  
High Repetition ◽  
Automatic Estimation ◽  
Vertical Drift ◽  
Electron Density Irregularities ◽  
Ionospheric Sounding

We propose and test a method of analyzing ionograms of vertical ionospheric sounding, which is based on detecting deviations of the shape of an ionogram from its regular (averaged) shape. We interpret these deviations in terms of reflection from the electron density irregularities at heights corresponding to the effective height. We examine the irregularities thus discovered within the framework of a model of a localized uniformly moving irregularity, and determine their characteristic parameters: effective heights and observed vertical velocities. We analyze selected experimental data for three seasons (spring, winter, autumn) obtained nearby Irkutsk with a fast chirp ionosonde of ISTP SB RAS in 2013–2015. The analysis of six days of observations conducted in these seasons has shown that in the observed vertical drift of the irregularities there are two characteristic distributions: wide velocity distribution with nearly 0 m/s mean and with standard deviation of ~250 m/s and narrow distribution with nearly –160 m/s mean. The analysis has demonstrated the effectiveness of the proposed algorithm for the automatic analysis of vertical sounding data with high repetition rate.

scholarly journals Automatic estimation of dynamics of ionospheric disturbances with 1–15 minute lifetimes as derived from ISTP SB RAS fast chirp-ionosonde data

2018 ◽  
Vol 4 (1) ◽  
pp. 76-84
Author(s):  
Олег Бернгардт ◽  
Oleg Berngardt ◽  
Татьяна Бубнова ◽  
Tatyana Bubnova ◽  
Алексей Подлесный ◽  
...  
Keyword(s):  
Experimental Data ◽  
High Repetition Rate ◽  
Ionospheric Disturbances ◽  
Characteristic Parameters ◽  
Effective Height ◽  
High Repetition ◽  
Automatic Estimation ◽  
Vertical Drift ◽  
Electron Density Irregularities ◽  
Ionospheric Sounding

We propose and test a method of analyzing ionograms of vertical ionospheric sounding, which is based on detecting deviations of the shape of an ionogram from its regular (averaged) shape. We interpret these deviations in terms of reflection from the electron density irregularities at heights corresponding to the effective height. We examine the irregularities thus discovered within the framework of a model of a localized uniformly moving irregularity, and determine their characteristic parameters: effective heights and observed vertical velocities. We analyze selected experimental data for three seasons (spring, winter, autumn) obtained nearby Irkutsk with a fast chirp ionosonde of ISTP SB RAS in 2013–2015. The analysis of six days of observations conducted in these seasons has shown that in the observed vertical drift of the irregularities there are two characteristic distributions: wide velocity distribution with nearly 0 m/s mean and with standard deviation of ~250 m/s and narrow distribution with nearly –160 m/s mean. The analysis has demonstrated the effectiveness of the proposed algorithm for the automatic analysis of vertical sounding data with high repetition rate.

A Quick Sorting Algorithm Adaptive to Massive Data with High Repetition Rate

2013 ◽  
Vol 834-836 ◽  
pp. 1002-1005
Author(s):  
Bao Ping Chen
Keyword(s):  
Experimental Data ◽  
Theoretical Analysis ◽  
Repetition Rate ◽  
Time Complexity ◽  
High Repetition Rate ◽  
Sorting Algorithm ◽  
Massive Data ◽  
Recursive Algorithms ◽  
High Repetition ◽  
Sorting Algorithms

Quick sorting is one of the sorting algorithms with good performance. However, there is a bottleneck of its performance in dealing with massive data with high repetition rate. Therefore, a new effective quick sorting algorithm is proposed in this study. This approach possesses the advantage of conciseness of quick sorting algorithms while avoiding the disadvantages of recursive algorithms. The time complexity is O(n), and the space complexity is O(1). Theoretical analysis and experimental data have shown that its performance is superior to the original quick sorting algorithm, and it is applicable to the processing of massive data with high repetition rate.

Ti3C2Tx nanosheets for high-repetition-rate wideband-tunable Q-switched fiber laser around 3 μm

2021 ◽  
pp. 1-1
Author(s):  
Liqiang Zhou ◽  
Chen Wei ◽  
Dongsheng Wang ◽  
Hao Chi ◽  
Le Zheng ◽  
...  
Keyword(s):  
Fiber Laser ◽  
Repetition Rate ◽  
High Repetition Rate ◽  
High Repetition

scholarly journals Ultrafast Third-Order Nonlinear Optical Response Excited by fs Laser Pulses at 1550 nm in GaN Crystals

Materials ◽  
2021 ◽  
Vol 14 (12) ◽  
pp. 3194
Author(s):  
Adrian Petris ◽  
Petronela Gheorghe ◽  
Tudor Braniste ◽  
Ion Tiginyanu
Keyword(s):  
Harmonic Generation ◽  
Nonlinear Optical ◽  
Laser Pulses ◽  
Third Harmonic Generation ◽  
High Repetition Rate ◽  
Third Order ◽  
Third Harmonic ◽  
The Third ◽  
High Repetition ◽  
Gan Crystal

The ultrafast third-order optical nonlinearity of c-plane GaN crystal, excited by ultrashort (fs) high-repetition-rate laser pulses at 1550 nm, wavelength important for optical communications, is investigated for the first time by optical third-harmonic generation in non-phase-matching conditions. As the thermo-optic effect that can arise in the sample by cumulative thermal effects induced by high-repetition-rate laser pulses cannot be responsible for the third-harmonic generation, the ultrafast nonlinear optical effect of solely electronic origin is the only one involved in this process. The third-order nonlinear optical susceptibility of GaN crystal responsible for the third-harmonic generation process, an important indicative parameter for the potential use of this material in ultrafast photonic functionalities, is determined.

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