Atmospheric parameters at the 6-m Big Telescope Alt-azimuthal site

2020 ◽  
Vol 493 (1) ◽  
pp. 723-729 ◽  
Author(s):  
A Yu Shikhovtsev ◽  
L A Bolbasova ◽  
P G Kovadlo ◽  
A V Kiselev
Keyword(s):  
Wind Speed ◽  
Adaptive Optics ◽  
Analysis Data ◽  
Special Astrophysical Observatory ◽  
Optical Telescope ◽  
The Caucasus ◽  
The Earth ◽  
Astronomical Images ◽  
Environmental Prediction

ABSTRACT In this paper, we introduce the results of the statistical analysis of atmospheric characteristics at the site of the Big Telescope Alt-azimuthal (BTA) of the Special Astrophysical Observatory (SAO) of the Russian Academy of Science (RAS). The BTA is the largest optical telescope in Eurasia and is located near Mt Pastukhova in the northern part of the Caucasus Mountains, at an altitude of 2070 m above sea level. The atmosphere of the Earth is a major challenge for observing and it limits the quality of astronomical images obtained by ground-based telescopes. The study of the atmosphere above astronomical observatories is important for the planning of observing time, for the optimization of instrument performance and for the development of adaptive optics systems. We discuss the results of a study of the meteorological conditions at the BTA site: total cloud cover, wind speed at the pressure level of 200 hPa, vertical motions, vertical profiles of the wind speed employing data from the ERA-Interim and National Centers for Environmental Prediction/National Center for Atmospheric Research (NCEP/NCAR) re-analysis data bases.

An Efficient Hybrid Forecasting Approach for Wind Speed Time Series

2017 ◽  
Vol 7 (9) ◽  
pp. 13
Author(s):  
Bhargavi Munnaluri ◽  
K. Ganesh Reddy
Keyword(s):  
Neural Networks ◽  
Artificial Neural Networks ◽  
Wind Speed ◽  
Fossil Fuels ◽  
Renewable Energy Sources ◽  
Support Vector ◽  
Hybrid Forecasting ◽  
Artificial Neural ◽  
Future Utilization

Wind forecasting is one of the best efficient ways to deal with the challenges of wind power generation. Due to the depletion of fossil fuels renewable energy sources plays a major role for the generation of power. For future management and for future utilization of power, we need to predict the wind speed.  In this paper, an efficient hybrid forecasting approach with the combination of Support Vector Machine (SVM) and Artificial Neural Networks(ANN) are proposed to improve the quality of prediction of wind speed. Due to the different parameters of wind, it is difficult to find the accurate prediction value of the wind speed. The proposed hybrid model of forecasting is examined by taking the hourly wind speed of past years data by reducing the prediction error with the help of Mean Square Error by 0.019. The result obtained from the Artificial Neural Networks improves the forecasting quality.

PENGARUH KEPEMIMPINAN, KEPUASAN KERJA, QUALITY OF WORK LIFE TERHADAP KINERJA KARYAWAN MELALUI PERILAKU DI HOTEL DINASTI KOTA MAKASSAR

2020 ◽  
Vol 2 (1) ◽  
pp. 35-40
Author(s):  
Hastati Hastati ◽  
Hasanuddin Remmang ◽  
Cahyono Cahyono
Keyword(s):  
Job Satisfaction ◽  
Path Analysis ◽  
Employee Performance ◽  
Descriptive Analysis ◽  
Analysis Data ◽  
Work Life ◽  
Quality Of Work Life ◽  
Employee Behavior ◽  
Quality Of Work

Penelitian ini bertujuan untuk mengkaji, menganalisis menginterprestasi kepemimpinan, kepuasan kerja, Quality of Work Life Terhadap Kinerja Karyawan Melalui Perilaku Pada Hotel Dinasti Kota Makassar. Penelitian ini bersifat deskriftip analisis dengan menggunakan pendekatan kuantitatif dan pendekatan kualitatif. dan metode analisis yang digunakan Analisis Path/ Path Analysis. Data diperoleh dari Hotel Dinasti Kota Makassar dan Responden adalah karyawan. Hasil penelitian ini dapat menemukan bebe-rapa faktor yang mempengaruhi kinerja karyawan di Hotel Dinasti Kota Makassar, antara lain Kepemimpinan, Kepuasan Kerja, Quality of Work Life dan Perilaku. Kepemimpinan berpengaruh positif dan signifikan terhadap perilaku karyawan. Kepuasan kerja berpengaruh positif dan signifikan terhadap perilaku karyawan. Quality of Work Life berpengaruh positif dan signifikan ter-hadap perilaku karyawan. Kepemimpinan berpengaruh positif dan signifikan terhadap kinerja karyawan melalui perilaku karya-wan. Kepuasan kerja berpengaruh positif dan signifikan terhadap kinerja karyawan melalui perilaku karyawan. Quality of Work Life berpengaruh positif dan signifikan terhadap kinerja karyawan melalui perilaku karyawan.  This study aims to examine, analyze leadership interpretation, job satisfaction, Quality of Work Life Against Employee Performance Through Behavior at the Hotel Dynasty Makassar City. This research is a descriptive analysis using a quantitative approach and a qualitative approach. And the analytical method used is Path Analysis. Data obtained from the Hotel Dynasty Makassar City and respondents were employees. The results of this study can find several factors that affect employee performance in the Makassar City Dynasty Hotel. These include leadership, job satisfaction, quality of work life and behavior. Leadership has a positive and significant effect on employee behavior. Job satisfaction has a positive and significant effect on employee behavior. Quality of Work Life has a positive and significant effect on employee behavior. Leadership has a positive and significant effect on employee performance through employee behavior. Job satisfaction has a positive and significant effect on employee performance through employee behavior. Quality of Work Life has a positive and significant effect on employee performance through employee behavior.

scholarly journals Nutritional Quality of Pasta Sold on the Italian Market: The Food Labelling of Italian Products (FLIP) Study

Nutrients ◽  
2021 ◽  
Vol 13 (1) ◽  
pp. 171
Author(s):  
Marika Dello Russo ◽  
Carmela Spagnuolo ◽  
Stefania Moccia ◽  
Donato Angelino ◽  
Nicoletta Pellegrini ◽  
...  
Keyword(s):  
Salt Content ◽  
Analysis Data ◽  
Food Choices ◽  
Nutritional Composition ◽  
Food Labels ◽  
Nutrition Claims ◽  
Italian Market ◽  
Lower Protein ◽  
Fresh Pasta

Pasta represents a staple food in many populations and, in recent years, an increasing number of pasta items has been placed on the market to satisfy needs and trends. The aims of this work were: (i) to investigate the nutritional composition of the different types of pasta currently sold in Italy by collecting the nutrition facts on their packaging; (ii) to compare energy, nutrient and salt content per 100 g and serving in fresh and dried pasta; (iii) to compare the nutrition declaration in pairs of products with and without different declarations (i.e., gluten free (GF), organic, and nutrition claims (NC)). A total of 756 items, made available by 13 retailers present on the Italian market, were included in the analysis. Data showed a wide difference between dried and fresh pasta, with high inter-type variability. A negligible amount of salt was observed in all types of pasta, except for stuffed products, which had a median high quantity of salt (>1 g/100 g and ~1.5 g/serving). Organic pasta had higher fibre and lower protein contents compared to conventional pasta. GF products were higher in carbohydrate and fat but lower in fibre and protein than not-GF products, while only a higher fibre content was found in pasta with NC compared to products not boasting claims. Overall, the results show high variability in terms of nutrition composition among the pasta items currently on the market, supporting the importance of reading and understanding food labels for making informed food choices.

Alexander and the Mongols

1979 ◽  
Vol 111 (2) ◽  
pp. 123-136 ◽  
Author(s):  
John Andrew Boyle
Keyword(s):  
Eighth Century ◽  
Alexander The Great ◽  
The Caucasus ◽  
The North ◽  
The Earth ◽  
Four Corners ◽  
Book Of Genesis ◽  
First Time

The association of Alexander the Great with the Mongols begins with the identification of the latter with the peoples of Gog and Magog. The evolution of this legend, which has its origin in the Book of Genesis, is curious in the extreme. In Genesis Magog is mentioned as one of the sons of Japhet, his name occurring between those of Gomer and Madai. Since Madai is clearly intended as the eponym of the Medes and Gomer has been located in Cappadocia and Phrygia it has been plausibly suggested that Magog at this stage corresponded to the territory in between, i.e. the region immediately south of the Caucasus in Eastern and Northern Armenia. In Ezekiel we hear for the first time of Gog “of the land of Magog”, who will come from his place out of the uttermost parts of the north, he and many peoples with him, “all of them riding on horses, a great company and a mighty army.” It will be seen that the “land of Magog” can no longer be located south of the Caucasus, and indeed Ezekiel's prophecy of the invasion of Gog has been interpreted as an echo of the invasions of the Cimmerians, who came southwards from the steppes through the Darial pass towards the end of the eighth century B.C.; or more probably of the invasion of the Scythians which took place in the following century by way of Darband. Finally we are told in Revelation that “when the thousand years are finished, Satan shall be loosed out of his prison, and shall come forth to deceive the nations which are in the four corners of the earth, Gog and Magog, to gather them together to the war; the number of whom is as the sand of the sea”.

scholarly journals Image data of crumb structure of bread from flour of czech spring wheat cultivars

2011 ◽  
Vol 22 (No. 4) ◽  
pp. 133-142 ◽  
Author(s):  
I. Švec ◽  
M. Hrušková
Keyword(s):  
Image Analysis ◽  
Image Data ◽  
Analysis Data ◽  
Wheat Cultivars ◽  
Rheological Measurements ◽  
Class A ◽  
Bread Volume ◽  
Class B ◽  
Crumb Structure

Abstract: Baking quality of flour from six wheat cultivars (harvest 2002 and 2003), belonging to the quality classes A and B, was evaluated using the fermented dough test. Analytical traits of kernel and flour showed differences between the classes which were confirmed by the baking test with the full-bread-formula according to Czech method. In addition to standard methods of the bread parameters description (specific bread volume and bread shape measurements) rheological measurements of penetrometer and image analysis were used in effort to differentiate wheat samples into the quality classes. The results of the baking test proved significant differences in specific bread volumes – the highest volume in class A was obtained with the cultivar Vinjet and in class B with SG-S1098 – approx. 410 and 420 ml/100 g. Although significant correlations among image analysis data and specific bread volume having been proved, any image analysis parameter did not distinguish the quality classes. Only the penetronetric measurements made with bread crumb were suitable for such purpose (r = 0.9083; for  = 0.01). Among image analysis data the total cell area of the crumb had the strongest correlation with specific bread volume (r = 0.7840; for α = 0.01).    

scholarly journals Successful application of PSF-R techniques to the case of the globular cluster NGC 6121 (M 4)

2020 ◽  
Vol 634 ◽  
pp. L5 ◽  
Author(s):  
D. Massari ◽  
A. Marasco ◽  
O. Beltramo-Martin ◽  
J. Milli ◽  
G. Fiorentino ◽  
...  
Keyword(s):  
Adaptive Optics ◽  
Globular Cluster ◽  
Hybrid Technique ◽  
Large Telescope ◽  
Point Spread ◽  
Accurate Knowledge ◽  
Viable Solution ◽  
Spread Function ◽  
Astronomical Images ◽  
Proper Analysis

Context. Precise photometric and astrometric measurements on astronomical images require an accurate knowledge of the point spread function (PSF). When the PSF cannot be modelled directly from the image, PSF-reconstruction techniques become the only viable solution. So far, however, their performance on real observations has rarely been quantified. Aims. In this Letter, we test the performance of a novel hybrid technique, called PRIME, on Adaptive Optics-assisted SPHERE/ZIMPOL observations of the Galactic globular cluster NGC 6121. Methods. PRIME couples PSF-reconstruction techniques, based on control-loop data and direct image fitting performed on the only bright point-like source available in the field of view of the ZIMPOL exposures, with the aim of building the PSF model. Results. By exploiting this model, the magnitudes and positions of the stars in the field can be measured with an unprecedented precision, which surpasses that obtained by more standard methods by at least a factor of four for on-axis stars and by up to a factor of two on fainter, off-axis stars. Conclusions. Our results demonstrate the power of PRIME in recovering precise magnitudes and positions when the information directly coming from astronomical images is limited to only a few point-like sources and, thus, paving the way for a proper analysis of future Extremely Large Telescope observations of sparse stellar fields or individual extragalactic objects.

scholarly journals 1178 J, 527 nm near diffraction limited laser based on a complete closed-loop adaptive optics controlled off-axis multi-pass amplification laser system

2021 ◽  
Vol 9 ◽  
Author(s):  
Deen Wang ◽  
Xin Zhang ◽  
Wanjun Dai ◽  
Ying Yang ◽  
Xuewei Deng ◽  
...  
Keyword(s):  
Laser Beam ◽  
Adaptive Optics ◽  
Closed Loop ◽  
Focal Spot ◽  
Beam Quality ◽  
Laser System ◽  
Diffraction Limit ◽  
Kdp Crystal ◽  
Main Amplifier

Abstract A 1178 J near diffraction limited 527 nm laser is realized in a complete closed-loop adaptive optics (AO) controlled off-axis multi-pass amplification laser system. Generated from a fiber laser and amplified by the pre-amplifier and the main amplifier, a 1053 nm laser beam with the energy of 1900 J is obtained and converted into a 527 nm laser beam by a KDP crystal with 62% conversion efficiency, 1178 J and beam quality of 7.93 times the diffraction limit (DL). By using a complete closed-loop AO configuration, the static and dynamic wavefront distortions of the laser system are measured and compensated. After correction, the diameter of the circle enclosing 80% energy is improved remarkably from 7.93DL to 1.29DL. The focal spot is highly concentrated and the 1178 J, 527 nm near diffraction limited laser is achieved.

Basic communication sciences

1969 ◽  
Vol 308 (1493) ◽  
pp. 183-198
Keyword(s):  
Long Distance ◽  
Earth Station ◽  
Early Communication ◽  
Technical Developments ◽  
Radiated Power ◽  
The Earth ◽  
Distance Communication ◽  
Quality Of Transmission ◽  
Communication Equipment

The feasibility and utility of long-distance communication via Earth-orbiting satellites has been demonstrated during recent years and it is appropriate therefore to focus attention on the more important scientific studies and technical developments that will be needed if full use is to be made of this valuable mode of communication in the future. The early communication satellites (the Telstar and Relay series) were pioneers in a relatively unknown propagation environment. The satellites themselves were conceptually simple and the communication equipment consisted essentially of a frequency-changing transponder with an r. f. power output of a few watts and a bandwidth some tens of megahertz. Carrier frequencies in the range 2 to 6 GHz were employed; typically either 2 or 6 GHz was used for transmission and 4 GHz for reception at the Earth station. To obtain an adequate signal/noise ratio at the output of the Earth station receiver, frequency modulation was employed, the frequency deviations being greater than those used on terrestrial microwave links. Launcher limitations and other factors meant that the satellites had to be placed in inclined elliptical orbits (see figure 1) with maximum heights of only a few thousand miles. Nevertheless, these satellites demonstrated that some hundreds of frequency-division multiplex telephony circuits, or a television channel, could be achieved with generally satisfactory quality of transmission. It is to be noted, however, that the satellite transponders accommodated only one, or at the most two, r. f. carriers at any time, and that the transmission performance was at times marginal due to limitations of the satellite effective radiated power. Furthermore, these relatively low orbit satellites provided communication in periods of generally less than an hour at a time and required continuous tracking by the Earth station aerials, due to movement of the satellites relative to the Earth.

Calibration and Validation of Infrared Sounders with Moon and Mercury

2021 ◽  
Author(s):  
Martin Burgdorf ◽  
Stefan A. Buehler ◽  
Viju John ◽  
Thomas Müller ◽  
Marc Prange
Keyword(s):  
Large Time ◽  
Angular Resolution ◽  
The Moon ◽  
Photometric Calibration ◽  
The Earth ◽  
Spread Function ◽  
Spectral Channels ◽  
Better Than ◽  
Full Disk

<p>Serendipitous observations of airless bodies of the inner solar system provide a unique means to the calibration of instruments on meteorological research satellites, because the physical properties of their surfaces change very little, even on large time scales. We investigated how certain instrumental effects can be characterised with observations of the Moon and Mercury. For this we identified and analysed intrusions of the Moon in the deep space views of HIRS/2, /3, and /4 (High-resolution Infrared Sounder) on various satellites in polar orbits and as well some images obtained with SEVIRI (Spinning Enhanced Visible Infra-Red Imager) on MSG-3 and -4 (Meteosat Second Generation), which had Mercury standing close to the Earth in the rectangular field of view.</p><p>A full-disk, infrared Moon model was developed that describes how the lunar flux density depends on phase angle and wavelength. It is particularly helpful for inter-calibration, checks of the photometric consistency of the sounding channels, and the calculation of an upper limit on the non-linearity of the shortwave channels of HIRS. In addition, we used the Moon to determine the co-registration of the different spectral channels.</p><p>Studies of the channel alignment are also presented for SEVIRI, an infrared sounder with an angular resolution about a hundred times better than HIRS. As we wanted to check the image quality of this instrument with a quasi-point source as well, we replaced here the Moon with Mercury. We found the typical smearing of the point spread function in the scan direction and occasionally a nearby ghost image, which is three to four times fainter than the main image of the planet. Both effects cause additional uncertainties of the photometric calibration.  </p>

Sign in / Sign up

Export Citation Format

Share Document