scholarly journals Propagation conditions of 10 MHz signals along the paths between Rostov and Moscow

2021 ◽  
Vol 2094 (2) ◽  
pp. 022033
Author(s):  
I Ivanov ◽  
O Maltseva ◽  
T Nikitenko
Keyword(s):  
Solar Activity ◽  
Ionospheric Disturbances ◽  
Model Calculations ◽  
Exact Time ◽  
Maximum Usable Frequency ◽  
Ionospheric Models ◽  
Cycle 24 ◽  
Joint Experiment ◽  
Comprehensive Study

Abstract To determine the conditions for the propagation of HF signals through the ionosphere along various paths, there are several possibilities: (1) ionograms of vertical sounding, (2) ionograms of oblique sounding between transmission and receiver points, (3) receiving signals from transmitters of exact time at fixed frequencies (here ~10 MHz), (4) using ionospheric models. This paper presents the results of a comprehensive study that implements all these possibilities. They refer to the propagation of HF signals on reciprocal paths between Rostov and Moscow during the period of the lowest solar activity of cycle 24 (April-May 2020). It is shown that the maximum usable frequency (MUF) of propagation through the F2 layer of the ionosphere in the overwhelming majority of cases did not exceed 10 MHz both in the experiment and according to model calculations. The signals were propagated through the Es layer. If earlier it was shown that such a joint experiment allows revealing the presence of traveling ionospheric disturbances, the results of this work emphasize the role of the Es layer.

scholarly journals MANIFESTATION OF SOLAR ACTIVITY AND DYNAMICS OF THE ATMOSPHERE IN VARIATIONS OF 577.7 AND 630.0 nm ATMOSPHERIC EMISSIONS IN SOLAR CYCLE 24

2020 ◽  
Vol 6 (3) ◽  
pp. 81-85
Author(s):  
Aleksandr Mikhalev
Keyword(s):  
Solar Activity ◽  
Solar Cycle ◽  
Atomic Oxygen ◽  
Correlation Coefficients ◽  
Atmospheric Emissions ◽  
Annual Average ◽  
Solar Cycle 24 ◽  
Cycle 24 ◽  
Activity Indices

In the paper, variations of the night emission intensities in the 557.7 and 630 nm atomic oxygen lines [OI] in 2011–2019 have been analyzed. The analysis is based on data from the ISTP SB RAS Geophysical Observatory. The emission intensities are compared with atmospheric, solar, and geophysical parameters. High correlation coefficients between monthly average and annual average 630.0 nm emission intensities and solar activity indices F10.7 have been obtained. This suggests a key role of solar activity in variations of this emission in the period of interest. Variations of the 557.7 nm emission demonstrate to a greater extent the correlations of the stratospheric zonal wind (QBO.U30 index) with quasi-biennial oscillations. The causes of the weak dependence of the 557.7 nm emission intensity on solar activity in solar cycle 24 are discussed.

scholarly journals MANIFESTATION OF SOLAR ACTIVITY AND DYNAMICS OF THE ATMOSPHERE IN VARIATIONS OF 577.7 AND 630.0 nm ATMOSPHERIC EMISSIONS IN SOLAR CYCLE 24

2020 ◽  
Vol 6 (3) ◽  
pp. 99-104
Author(s):  
Aleksandr Mikhalev
Keyword(s):  
Solar Activity ◽  
Solar Cycle ◽  
Atomic Oxygen ◽  
Correlation Coefficients ◽  
Atmospheric Emissions ◽  
Annual Average ◽  
Solar Cycle 24 ◽  
Cycle 24 ◽  
Activity Indices

In the paper, variations of the night emission intensities in the 557.7 and 630 nm atomic oxygen lines [OI] in 2011–2019 have been analyzed. The analysis is based on data from the ISTP SB RAS Geophysical Observatory. The emission intensities are compared with atmospheric, solar, and geophysical parameters. High correlation coefficients between monthly average and annual average 630.0 nm emission intensities and solar activity indices F10.7 have been obtained. This suggests a key role of solar activity in variations of this emission in the period of interest. Variations of the 557.7 nm emission demonstrate to a greater extent the correlations of the stratospheric zonal wind (QBO.U30 index) with quasi-biennial oscillations. The causes of the weak dependence of the 557.7 nm emission intensity on solar activity in solar cycle 24 are discussed.

Influence of Magnetic Fields on Solar Hydrodynamics: Experimental Results

1977 ◽  
Vol 36 ◽  
pp. 143-180 ◽  
Author(s):  
J.O. Stenflo
Keyword(s):  
Solar Activity ◽  
Energy Balance ◽  
Magnetic Fields ◽  
Solar Atmosphere ◽  
General Problem ◽  
Solar Rotation ◽  
Active Regions ◽  
Physical Conditions ◽  
Dynamic Phenomena

It is well-known that solar activity is basically caused by the Interaction of magnetic fields with convection and solar rotation, resulting in a great variety of dynamic phenomena, like flares, surges, sunspots, prominences, etc. Many conferences have been devoted to solar activity, including the role of magnetic fields. Similar attention has not been paid to the role of magnetic fields for the overall dynamics and energy balance of the solar atmosphere, related to the general problem of chromospheric and coronal heating. To penetrate this problem we have to focus our attention more on the physical conditions in the ‘quiet’ regions than on the conspicuous phenomena in active regions.

The Role of the Internet of Things in Health Care: A Systematic and Comprehensive Study

2020 ◽  
Author(s):  
Navod Neranjan Thilakarathne ◽  
Mohan Krishna Kagita ◽  
Thippa Reddy Gadekallu
Keyword(s):  
Health Care ◽  
Internet Of Things ◽  
The Internet ◽  
The Internet Of Things ◽  
Comprehensive Study

Dietary Carotenoids in Managing Metabolic Syndrome and Role of PPARs in the Process

2020 ◽  
Vol 16 (6) ◽  
pp. 846-853
Author(s):  
Raghunandan Purohith ◽  
Nagendra P.M. Nagalingaswamy ◽  
Nanjunda S. Shivananju
Keyword(s):  
Metabolic Syndrome ◽  
Dietary Intervention ◽  
Bioactive Constituents ◽  
Dietary Antioxidants ◽  
Predisposing Factor ◽  
Beneficial Effects ◽  
Pathological Conditions ◽  
Established Relationship ◽  
Comprehensive Study

Metabolic syndrome is a collective term that denotes disorder in metabolism, symptoms of which include hyperglycemia, hyperlipidemia, hypertension, and endothelial dysfunction. Diet is a major predisposing factor in the development of metabolic syndrome, and dietary intervention is necessary for both prevention and management. The bioactive constituents of food play a key role in this process. Micronutrients such as vitamins, carotenoids, amino acids, flavonoids, minerals, and aromatic pigment molecules found in fruits, vegetables, spices, and condiments are known to have beneficial effects in preventing and managing metabolic syndrome. There exists a well-established relationship between oxidative stress and major pathological conditions such as inflammation, metabolic syndrome, and cancer. Consequently, dietary antioxidants are implicated in the remediation of these complications. The mechanism of action and targets of dietary antioxidants as well as their effects on related pathways are being extensively studied and elucidated in recent times. This review attempts a comprehensive study of the role of dietary carotenoids in alleviating metabolic syndromewith an emphasis on molecular mechanism-in the light of recent advances.

scholarly journals Role of Single-Particle Energies in Microscopic Interacting Boson Model Double Beta Decay Calculations

Universe ◽  
2021 ◽  
Vol 7 (3) ◽  
pp. 66
Author(s):  
Jenni Kotila
Keyword(s):  
Beta Decay ◽  
Single Particle ◽  
Field Potential ◽  
Double Beta Decay ◽  
Interacting Boson Model ◽  
Model Calculations ◽  
Single Particle Level ◽  
Particle Level ◽  
Boson Model

Single-particle level energies form a significant input in nuclear physics calculations where single-particle degrees of freedom are taken into account, including microscopic interacting boson model investigations. The single-particle energies may be treated as input parameters that are fitted to reach an optimal fit to the data. Alternatively, they can be calculated using a mean field potential, or they can be extracted from available experimental data, as is done in the current study. The role of single-particle level energies in the microscopic interacting boson model calculations is discussed with special emphasis on recent double beta decay calculations.

scholarly journals A comprehensive study on the role of advanced technologies in 5G based smart hospital

2021 ◽  
Vol 60 (6) ◽  
pp. 5527-5536
Author(s):  
Arun Kumar ◽  
R. Dhanagopal ◽  
Mahmoud A. Albreem ◽  
Dac-Nhuong Le
Keyword(s):  
Advanced Technologies ◽  
Smart Hospital ◽  
Comprehensive Study

Role of ion transfer processes in acid-base regulation with temperature changes in fish

1984 ◽  
Vol 246 (4) ◽  
pp. R441-R451 ◽  
Author(s):  
N. Heisler
Keyword(s):  
Ion Transfer ◽  
Bicarbonate Concentration ◽  
Acid Base ◽  
Fish Tissues ◽  
Model Calculations ◽  
Temperature Changes ◽  
Transfer Processes ◽  
Transfer Mechanisms

The contributions of transmembrane and transepithelial ion transfer processes and of nonbicarbonate buffering to the in vivo acid-base regulation have been evaluated. Model calculations were performed utilizing experimental data on transepithelial transfer of ions relevant for the acid-base regulation, the intracellular buffering properties of fish tissues, and the behavior of intracellular and extracellular pH and bicarbonate concentration with changes of temperature. The results of these studies indicate that the changes in the pK values of physiological nonbicarbonate buffers with changes in temperature support the adjustment of pH to lower values with rising temperature; however, transmembrane and transepithelial ion transfer mechanisms determine the acid-base regulation of intracellular and extracellular compartments.

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