scholarly journals Siberian Radioheliograph: first results

2017 ◽  
Vol 3 (1) ◽  
pp. 3-16 ◽  
Author(s):  
Сергей Лесовой ◽  
Sergey Lesovoi ◽  
Александр Алтынцев ◽  
Alexander Altyntsev ◽  
Алексей Кочанов ◽  
...  
Keyword(s):  
Solar Flares ◽  
High Sensitivity ◽  
Solar Flux ◽  
Microwave Emission ◽  
Accumulation Time ◽  
Operating Frequency Range ◽  
First Results ◽  
Siberian Solar Radio Telescope ◽  
Active Processes ◽  
Compact Sources

Regular observations of active processes in the solar atmosphere have been started using the first stage of the multiwave Siberian Radioheliograph (SRH), a T-shaped 48-antenna array with a 4–8 GHz operating frequency range and a 10 MHz instantaneous receiving band. Antennas are set on the central antenna posts of the Siberian Solar Radio Telescope. The maximum baseline is 107.4 m, and the angular resolution is up to 70ʹʹ. We present examples of observations of the solar disk at different frequencies, “negative” bursts, and solar flares. The sensitivity to compact sources reaches 0.01 solar flux units (≈10^{-4} of the total solar flux) with an accumulation time of 0.3 s. The high sensitivity of the SRH enables monitoring of solar activity and allows one to study active processes from characteristics of their microwave emission, including faint events, which could not be detected previously.

scholarly journals Siberian Radioheliograph: first results

2017 ◽  
Vol 3 (1) ◽  
pp. 3-18 ◽  
Author(s):  
Сергей Лесовой ◽  
Sergey Lesovoi ◽  
Александр Алтынцев ◽  
Alexander Altyntsev ◽  
Алексей Кочанов ◽  
...  
Keyword(s):  
Solar Flares ◽  
High Sensitivity ◽  
Solar Flux ◽  
Microwave Emission ◽  
Accumulation Time ◽  
Operating Frequency Range ◽  
First Results ◽  
Siberian Solar Radio Telescope ◽  
Active Processes ◽  
Compact Sources

Regular observations of active processes in the solar atmosphere have been started using the first stage of the multiwave Siberian Radioheliograph (SRH), a T-shaped 48-antenna array with a 4–8 GHz operating frequency range and a 10 MHz instantaneous receiving band. Antennas are mounted on the central antenna posts of the Siberian Solar Radio Telescope. The maximum baseline is 107.4 m, and the angular resolution is up to 70". We present examples of observations of the solar disk at different frequencies, “negative” bursts, and solar flares. The sensitivity to compact sources reaches 0.01 solar flux units (≈10^{-4} of the total solar flux) with an accumulation time of about 0.3 s. The high sensitivity of SRH enables monitoring of solar activity and allows studying active processes from characteristics of their microwave emission, including faint events, which could not be detected previously.

scholarly journals Long period oscillations of microwave emission of solar active regions: observations with NoRH and SSRT

2008 ◽  
Vol 4 (S257) ◽  
pp. 155-157 ◽  
Author(s):  
I. A. Bakunina ◽  
V. E. Abramov-Maximov ◽  
S. V. Lesovoy ◽  
K. Shibasaki ◽  
A. A. Solov'ev ◽  
...  
Keyword(s):  
Solar Radio ◽  
Large Time ◽  
High Spatial Resolution ◽  
Active Regions ◽  
Microwave Emission ◽  
Long Period ◽  
Common Time ◽  
First Results ◽  
Siberian Solar Radio Telescope

AbstractIn this work we present the first results of study and comparison of the parameters of quasi-periodic long-term oscillations of microwave emission of large (>0.7 arcmin) sunspots as a result of simultaneous observations with two radioheliographs – NoRH (17 GHz) and Siberian Solar Radio Telescope (SSRT) (5.7 GHz) with 1 minute cadence. Radioheliographs have been working with quite large time overlap (about 5 hours) and have the high spatial resolution: 10 arcsec (NoRH) and 20 arcsec (SSRT). We have found that quasi-periodic long-term oscillations are surely observed at both frequencies with the periods in the range of 20–150 min. We detected common periods for common time of observations with two radioheliographs and interpret this as the consequence of the vertical-radial quasi-periodic displacements of sunspot as a whole structure.

Peculiarities of the microwave emission from active regions generating intense solar flares

2003 ◽  
Vol 29 (4) ◽  
pp. 263-273 ◽  
Author(s):  
V. M. Bogod ◽  
S. Kh. Tokhchukova
Keyword(s):  
Solar Flares ◽  
Active Regions ◽  
Microwave Emission

scholarly journals Diagnostics of the Internal Combustion Engines Operation by Measurement of Crankshaft Instantaneous Angular Speed

2019 ◽  
Vol 49 (4) ◽  
pp. 281-295
Author(s):  
Mirosław Dereszewski ◽  
Grzegorz Sikora
Keyword(s):  
Rotational Speed ◽  
Internal Combustion Engines ◽  
High Sensitivity ◽  
Relative Displacement ◽  
Angular Speed ◽  
Injection System ◽  
Combustion Engines ◽  
External Disturbances ◽  
Active Measurement ◽  
First Results

Abstract Diagnostics based on measuring of crankshaft instantaneous rotational speed allows precise location of damage to the injection system and detection of external disturbances. Active measurement of instantaneous rotational speed requires use of equipment with high sensitivity, permanent assembly at the ends of the crankshaft and the analysis of a very large amount of data. Presented method can be used for measurement of torsional vibration of crankshaft, indirectly through simultaneous measurement of the width of the pulses generated by the encoder disks. Momentary, relative displacement of both disks determines the angle of temporary crankshaft twisting. This paper presents first results of pulse width measurement, obtained by using described system.

scholarly journals Whisper voice test for screening of hearing loss in nursing home residents with cognitive impairmen

2021 ◽  
pp. 1-11
Author(s):  
Covadonga Vázquez-Sánchez ◽  
Luz Mª Gigirey
Keyword(s):  
Hearing Loss ◽  
Cognitive Impairment ◽  
Hearing Aids ◽  
Negative Impact ◽  
Test Procedure ◽  
Nursing Home Residents ◽  
High Sensitivity ◽  
Predictive Values ◽  
First Results ◽  
The Voice

Recent studies establish association between hearing loss and cognitive function and evidence exist that hearing damage can exacerbate the negative impact of cognitive impairment in quality of life. Prevalence of hearing loss increases among elderly people living in nursing homes, but the number of residents without hearing aids is high. Whisper voice test is a valid test for screening for hearing impairment. It is frequently used in Primary Care. We applied the voice test in older residents with cognitive impairment and we observed that these subjects failed the repetition of letters. Consequently, we decided to modify the habitual test procedure and employ familiar phrases as screening sound stimulus, on the assumption that they are more easily recognizable. The objective of our study is to establish whether this new technique can be used to screen for hearing loss in older people with mild-moderate cognitive impairment. 62 older residents (mini mental scores > 14) participated in this research. First results reveal that the voice test has high sensitivity and specificity, as well as elevated positive and negative predictive values. The proposed technique could be used as hearing screening tool in a population with similar characteristics.

Eine Methode zur Messung geringster Ölbedeckungen in Vakuumsystemen

1967 ◽  
Vol 22 (4) ◽  
pp. 549-553 ◽  
Author(s):  
R. Dobrozemsky ◽  
W. K. Huber ◽  
F. Viehböck
Keyword(s):  
High Vacuum ◽  
High Sensitivity ◽  
Radioactive Tracer ◽  
Operating Conditions ◽  
Ultra High Vacuum ◽  
Vacuum System ◽  
First Results ◽  
Tracer Isotope ◽  
Radioactive Tracer Method ◽  
Vacuum Systems

To get information on extremely small organic deposits in ultra high vacuum systems the sensitivity of most of the conventional methods for thickness measurements is not high enough. On the other hand the radioactive tracer method has shown its high sensitivity and wide versatility in many fields. Tritium with a half life of 12.3 γ and a mean β-energy of 5.4 keV was choosen as tracer isotope. A method is described for Tritium-labelling diffusion pump oils with specific activities up to 100 mC/g. Using the liquid scintillation counting technique one can detect deposits down to below 1010 molecules/cm2. First results with this Tritium labelled pump fluid are given under different operating conditions in an all metal ultra high vacuum system.

Microwave emission from hot X-ray kernels in solar flares

Solar Physics ◽  
1982 ◽  
Vol 81 (1) ◽  
pp. 121-135 ◽  
Author(s):  
V. V. Zheleznyakov ◽  
Yu. V. Tikhomirov
Keyword(s):  
Solar Flares ◽  
Microwave Emission ◽  
X Ray

scholarly journals THERMODYNAMIC SPECTRUM OF SOLAR FLARES BASED ON SDO /EVE OBSERVATIONS: TECHNIQUES AND FIRST RESULTS

2016 ◽  
Vol 223 (1) ◽  
pp. 4 ◽  
Author(s):  
Yuming Wang ◽  
Zhenjun Zhou ◽  
Jie Zhang ◽  
Kai Liu ◽  
Rui Liu ◽  
...  
Keyword(s):  
Solar Flares ◽  
First Results

scholarly journals Statistical studies of low-power solar flares. Distribution of flares by area, brightness, and classes

2017 ◽  
Vol 3 (1) ◽  
pp. 34-45 ◽  
Author(s):  
Александр Боровик ◽  
Aleksandr Borovik ◽  
Антон Жданов ◽  
Anton Zhdanov
Keyword(s):  
Low Power ◽  
Solar Flares ◽  
Software Package ◽  
Statistical Data ◽  
Correlation Coefficients ◽  
Flare Activity ◽  
The Sun ◽  
Electronic Database ◽  
First Results ◽  
Statistical Studies

An electronic database has been created for 123801 solar flares that occurred on the Sun over the period from 1972 to 2010. It is based on catalogs of the Solar Geophysical Data (SGD) and Quarterly Bulletin on Solar Activity. A software package has been used for statistical data preprocessing. The first results revealed a number of new features in the distribution of parameters of solar flares, which differ from those obtained previously. We have found that more than 90 % of all solar flares are low-power. The most numerous class comprises SF flares (64 %). Flare activity shows a pronounced cyclicity and high correlation with Wolf numbers. The highest correlation coefficients indicate S and 1 solar flares. There is also a high correlation between individual flare classes: S and 1, 1 and (2–4). The results obtained previously [Mitra et al., 1972] which provide evidence of the prevalence of SN solar flares (47 %) and the existence of significant peaks for SN and 1N flares, have not been confirmed. The distri-bution of the number of solar flares with increasing op-tical importance smoothly decreases without significant deviations. With increasing optical importance, solar flares are gradually redistributed toward an increase in brightness class. The excess of the number of SN and 1N solar flares present in the distributions obtained in [Mitra et al., 1972] are most likely associated with poor statistics.

scholarly journals Statistical studies of low-power solar flares. Distribution of flares by area, brightness, and classes

2017 ◽  
Vol 3 (1) ◽  
pp. 40-56 ◽  
Author(s):  
Александр Боровик ◽  
Aleksandr Borovik ◽  
Антон Жданов ◽  
Anton Zhdanov
Keyword(s):  
Low Power ◽  
Solar Flares ◽  
Software Package ◽  
Statistical Data ◽  
Correlation Coefficients ◽  
Flare Activity ◽  
The Sun ◽  
Electronic Database ◽  
First Results ◽  
Statistical Studies

An electronic database has been created for 123801 solar flares that occurred on the Sun over the period from 1972 to 2010. It is based on catalogs of the Solar Geophysical Data (SGD) and Quarterly Bulletin on Solar Activity. A software package has been used for statistical data preprocessing. The first results revealed a number of new features in the distribution of parameters of solar flares, which differ from those obtained previously. We have found that more than 90% of all solar flares are low-power. The most numerous class comprises SF flares (64%). Flare activity shows a pronounced cyclicity and high correlation with Wolf numbers. The highest correlation coefficients indicate S and 1 solar flares. There is also a high correlation between individual flare classes: S and 1, 1 and (2–4). The results obtained previously [Mitra et al., 1972] which provide evidence of the prevalence of SN solar flares (47%) and the existence of significant peaks for SN and 1N flares, have not been confirmed. The distribution of the number of solar flares with increasing optical importance smoothly decreases without significant deviations. With increasing optical importance, solar flares are gradually redistributed toward an increase in brightness class. The excess of the number of SN and 1N solar flares present in the distributions obtained in [Mitra et al., 1972] are most likely associated with poor statistics.

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