Short‐Fractional Hop Whistler Rate Observed by the Low‐Altitude Satellite DEMETER at the End of the Solar Cycle 23
For the first time an evaluation of the whistler rate around the Earth is performed using results
from the neural network aboard the microsatellite DEMETER. It is shown that the rate of whistlers with low
dispersion calculated all around the Earth as a function of longitude vary between 1 and 6 s−1 during
nighttime (22.30 LT) and between 0.5 and 0.7 s−1 during daytime (10.30 LT). The whistler rate is
anticorrelated with the F10.7‐cm solar flux. A decrease by 25% of the solar flux corresponds to an increase of
62% (26%) of the averaged whistler rate calculated for the entire Earth during nighttime (daytime). Using this
averaged whistler rate, the global lightning rate is estimated to be of the order of 123 s−1 (27 s−1) during
nighttime (daytime). The main conclusion concerns the precipitation of the electrons in the radiation belt by
interaction with the whistlers. It is shown that the decrease of the lightning activity at solar minimum
(shown with the help of the Schumann resonances) is largely counterbalanced by the increase of the whistler
rates in the upper part of the ionosphere due to the decrease of the ionospheric absorption.
The article discusses development of the segmented characters classifier of the Russian alphabet and of the Arabic numerals on the basis of block neural network structures including the plurality of blocks for each individual character recognition and for the synthesis block decision.
We examine the questions of applying large pyramidal neural (intellectual neuron) networks to solve equipment object control problems. We consider the description of a system for dynamic planning of mobile robot behavior, constructed based on a network of similar elements.
The task of improving the quality of forecasting returns of financial instruments using multivariate mathematical models: regression models and neural networks was analyzed. To construct a multifactor model of returns used the assumption on the influence of market factors that have a different nature. A linear multivariable regression model was constructed using stepwise inclusion algorithm. The multilayer neural network trained using back-propagation algorithm. The quality of the neural prediction models forecast much higher quality, built with the help of a regression model.
In this paper, the main purpose is to consider applications of morphological analysis in text classifiation. Morphological analysis helps us to learn grammatical features of words, grammatical semantic and the interaction between the elements of text. We propose the neurosemantic network based on morphological analysis for learning vector representations of the text’s grammatical structures and the recursive autoencoder that consists of two parts - the fist part combines two vectors of words, the second one combines two vectors of morphology.
The dynamics of a two-component Davydov-Scott (DS) soliton with a small mismatch of the initial location or velocity of the high-frequency (HF) component was investigated within the framework of the Zakharov-type system of two coupled equations for the HF and low-frequency (LF) fields. In this system, the HF field is described by the linear Schrödinger equation with the potential generated by the LF component varying in time and space. The LF component in this system is described by the Korteweg-de Vries equation with a term of quadratic influence of the HF field on the LF field. The frequency of the DS soliton`s component oscillation was found analytically using the balance equation. The perturbed DS soliton was shown to be stable. The analytical results were confirmed by numerical simulations.
By using superconducting quantum interference device (SQUID) magnetometry, we investigated anisotropic high-field (H less than or similar to 7T) low-temperature (10 K) magnetization response of inhomogeneous nanoisland FeNi films grown by rf sputtering deposition on Sitall (TiO2) glass substrates. In the grown FeNi films, the FeNi layer nominal thickness varied from 0.6 to 2.5 nm, across the percolation transition at the d(c) similar or equal to 1.8 nm. We discovered that, beyond conventional spin-magnetism of Fe21Ni79 permalloy, the extracted out-of-plane magnetization response of the nanoisland FeNi films is not saturated in the range of investigated magnetic fields and exhibits paramagnetic-like behavior. We found that the anomalous out-of-plane magnetization response exhibits an escalating slope with increase in the nominal film thickness from 0.6 to 1.1 nm, however, it decreases with further increase in the film thickness, and then practically vanishes on approaching the FeNi film percolation threshold. At the same time, the in-plane response demonstrates saturation behavior above 1.5-2T, competing with anomalously large diamagnetic-like response, which becomes pronounced at high magnetic fields. It is possible that the supported-metal interaction leads to the creation of a thin charge-transfer (CT) layer and a Schottky barrier at the FeNi film/Sitall (TiO2) interface. Then, in the system with nanoscale circular domains, the observed anomalous paramagnetic-like magnetization response can be associated with a large orbital moment of the localized electrons. In addition, the inhomogeneous nanoisland FeNi films can possess spontaneous ordering of toroidal moments, which can be either of orbital or spin origin. The system with toroidal inhomogeneity can lead to anomalously strong diamagnetic-like response. The observed magnetization response is determined by the interplay between the paramagnetic-and diamagnetic-like contributions.
Radiation conditions are described for various space regions, radiation-induced effects in spacecraft materials and equipment components are considered and information on theoretical, computational, and experimental methods for studying radiation effects are presented. The peculiarities of radiation effects on nanostructures and some problems related to modeling and radiation testing of such structures are considered.