scholarly journals Daily variations of the refractive index in the south of the Vitim plateau in different seasons of the year

2020 ◽  
Vol 196 ◽  
pp. 01003
Author(s):  
Aryuna Bazarova ◽  
Evgeniy Atutov ◽  
Alexander Bazarov ◽  
Yuri Bashkuev
Keyword(s):  
Refractive Index ◽  
Meteorological Parameters ◽  
Meteorological Data ◽  
Electronic Systems ◽  
Radio Waves ◽  
Climatic Regions ◽  
The Earth ◽  
Different Seasons ◽  
Pressure Water ◽  
The Republic

The urgency of the problem of studying the refractive properties of the troposphere is determined by the increasing rate of use of radio meteorological parameters in the design and operation of GLONASS-GPS and GSM radio-electronic systems in various physical and climatic regions of the Earth, in particular in eastern Russia. Specialists are faced with an urgent need to study the laws governing the propagation of VHF-UHF radio waves taking into account the influence of all layers of the atmosphere as a medium with a variable refractive index. The article presents the calculation of the refractive index N based on meteorological data of the atmospheric-soil measuring complex, located on the measuring station in the Eravninsky district of the Republic of Buryatia. The dependences of the refractive index on atmospheric pressure, water vapor elasticity, and absolute air temperature are established.

Variation of Radio Refractivity with Height above Ground

1970 ◽  
Vol 111 (5) ◽  
pp. 23-26 ◽  
Author(s):  
E. Valma ◽  
M. Tamosiunaite ◽  
S. Tamosiunas ◽  
M. Tamosiuniene ◽  
M. Zilinskas
Keyword(s):  
Refractive Index ◽  
Data Analysis ◽  
Seasonal Variations ◽  
Meteorological Parameters ◽  
Meteorological Data ◽  
Climatic Conditions ◽  
Earth Surface ◽  
International Telecommunications ◽  
The Earth

In Vilnius, the daily and the seasonal variations of the radio refractivity values have been computed at the Earth surface in the years 2005-2010 and at the heights up to 1.2 km in November 2010. The International Telecommunications Union - Radiocommunications Sector (ITU-R) model was used for calculation of the radio refractive index according to the peculiarities of climatic conditions of Lithuania. As a result of obtained data analysis, the days with more variable meteorological parameters have been chosen for more detailed investigation. The radio refractivity gradient has been computed at the heights starting from the Earth surface up to 1.2 km above the ground, using the meteorological data measured at those heights. The variation of radio refractivity and its gradient are influenced by the changes in air's humidity and temperature in most part. Ill. 7, bibl. 17, tabl. 1 (in English; abstracts in English and Lithuanian).http://dx.doi.org/10.5755/j01.eee.111.5.349

scholarly journals Refractive properties of the troposphere of Baikal natural territory and surrounding areas.

2021 ◽  
Author(s):  
A.S. Bazarova ◽  
◽  
R.S. Sychev ◽  
A.V. Bazarov ◽  
E.B. Atutov ◽  
...  
Keyword(s):  
Refractive Index ◽  
Global Climate ◽  
Meteorological Data ◽  
Radio Waves ◽  
Global Climate Changes ◽  
Regional Features ◽  
Meteorological Situation ◽  
Surrounding Areas ◽  
The Village ◽  
Meteorological Characteristic

Abstract. The meteorological situation has a significant impact on the propagation of ultrashort radio waves. Refractive index of the atmosphere N is the main radio-meteorological characteristic of UHW propagation. The calculation of N is given on the basis of meteorological data of the atmospheric-soil measuring complex located on the basis of the measuring station in the village. Sosnovo-Ozerskoe, Eravninsky District, Republic of Buryatia. The regional features of the behavior refractive index in Buryatia, Yakutia and Mongolia are considered. The comparison with similar studies carried out on the basis of meteorological data from 1958-1977 was made. Global climate changes did not have a significant impact on the radio meteorological situation in the region was revealed.

Ultra Short Baseline (USBL) Calibration for Positioning of Underwater Objects

2019 ◽  
Vol 2 (2) ◽  
pp. 73-85
Author(s):  
Bagus Septyanto ◽  
Dian Nurdiana ◽  
Sitti Ahmiatri Saptari
Keyword(s):  
Acoustic Wave ◽  
Scale Factor ◽  
Positioning System ◽  
Radio Waves ◽  
Short Baseline ◽  
Error Angle ◽  
Satellite Navigation System ◽  
The Earth ◽  
Underwater Positioning ◽  
Radio Signals

In general, surface positioning using a global satellite navigation system (GNSS). Many satellites transmit radio signals to the surface of the earth and it was detected by receiver sensors into a function of position and time. Radio waves really bad when spreading in water. So, the underwater positioning uses acoustic wave. One type of underwater positioning is USBL. USBL is a positioning system based on measuring the distance and angle. Based on distance and angle, the position of the target in cartesian coordinates can be calculated. In practice, the effect of ship movement is one of the factors that determine the accuracy of the USBL system. Ship movements like a pitch, roll, and orientation that are not defined by the receiver could changes the position of the target in X, Y and Z coordinates. USBL calibration is performed to detect an error angle. USBL calibration is done by two methods. In USBL calibration Single Position obtained orientation correction value is 1.13 ̊ and a scale factor is 0.99025. For USBL Quadrant calibration, pitch correction values is -1.05, Roll -0.02 ̊, Orientation 6.82 ̊ and scale factor 0.9934 are obtained. The quadrant calibration results deccrease the level of error position to 0.276 - 0.289m at a depth of 89m and 0.432m - 0.644m at a depth of 76m

HADIS KURAIB DALAM KONSEP RUKYATUL HILAL

1970 ◽  
Vol 13 (2) ◽  
Author(s):  
Muslih Husein
Keyword(s):  
The West ◽  
The Earth ◽  
New Moon ◽  
The Republic

Hisab dan rukyat, hakikatnya, adalah cara untuk mengetahui pergantian bulan. Kajian ini memperlihatkan beberapa temuan. Pertama, korelasi antara hadis Kuraib dan terjadinya perbedaan penetapan awal Ramadan, Syawal, dan Dzul Hijjah di Indonesia. Kementerian Agama Republik Indonesia telah menetapkan bahwa Indonesia secara keseluruhan menjadi satu wilayah hukum (wilayatul hukmi). Kedua, tentang keberhasilan rukyat al-hilal di satu kawasan yang diberlakukan bagi kawasan lain di muka bumi. Perlu diketahui bersama bahwa visibilitas pertama hilal tidak meliputi seluruh muka bumi pada hari yang sama, melainkan membelahnya menjadi dua bagian: (1) bagian sebelah Barat yang dapat melihat hilal dan (2) bagian sebelah Timur yang tidak dapat melihat hilal.Hisab and rukyat is a way to know the turn of the month. This study shows several findings. First is the correlation between Kuraib traditions and differences in the determination of the beginning of Ramadan, Shawwal, and Dhul-Hijjah in Indonesia. Ministry of Religious Affairs of the Republic of Indonesia has stated that Indonesia as a whole into a single jurisdiction (wilayatul hukmi). Second, on the success rukyat alhilal in one area that applied to other regions of earth. Important to know that the first visibility of the new moon does not cover the entire face of the earth on the same day, but splitting it into two parts: (1) part of the West to see the new moon, and (2) part of the East were not able to see the new moon.

Automated Determination of the Position of Ships by Satellites

1967 ◽  
Vol 20 (03) ◽  
pp. 281-285
Author(s):  
H. C. Freiesleben
Keyword(s):  
Celestial Body ◽  
World Wide ◽  
Artificial Satellites ◽  
Radio Waves ◽  
The Moon ◽  
Position Determination ◽  
The Earth ◽  
Navigational Aids ◽  
Automated Determination

It has recently been suggested that 24-hour satellites might be used as navigational aids. To what category of position determination aids should these be assigned ? Is a satellite of this kind as it were a landmark, because, at least in theory, it remains fixed over the same point on the Earth's surface, in which case it should be classified under land-based navigation aids ? Is it a celestial body, although only one tenth as far from the Earth as the Moon ? If so, it is an astronomical navigation aid. Or is it a radio aid ? After all, its use for position determination depends on radio waves. In this paper I shall favour this last view. For automation is most feasible when an object of observation can be manipulated. This is easiest with radio aids, but it is, of course, impossible with natural stars.At present artificial satellites have the advantage over all other radio aids of world-wide coverage.

Hydro-meteorological data preparation for ecosystem hydrological modelling in the riparian forest of Hidegvíz Valley experimental catchment

2021 ◽  
Author(s):  
Csenge Nevezi ◽  
Tamás Bazsó ◽  
Zoltán Gribovszki ◽  
Előd Szőke ◽  
Péter Kalicz
Keyword(s):  
Air Temperature ◽  
Meteorological Parameters ◽  
Extreme Event ◽  
Riparian Forest ◽  
Meteorological Data ◽  
Rain Gauge ◽  
Hydrological Modelling ◽  
Data Preparation ◽  
Air Humidity ◽  
Groundwater Levels

<p>In the Hidegvíz Valley experimental catchment in Hungary the meteorological data have been collected since the 1990s and used for various purposes including hydrological studies. Current research began in 2018–19, that aimed to reveal the connections between the hydrological and botanical characteristics in riparian forests and a wet meadow. Changes that occurred in both ecosystems in the groundwater levels, soil moisture and vegetation, showed that the local meteorological events influence these factors. Therefore we decided to analyse longer periods in which meteorological extremes<br>strongly influenced hydrological conditions and so status of ecosystems. Further measurements and their analysis were also required because more accuracy and detail were needed for future water balance modelling.</p><p>The measured data between 2017–2020 were chosen as a starting database. For the first analysis we selected three meteorological parameters, i. e. the precipitation, the air temperature, and the air humidity. These parameters were measured by automated instruments, except for the precipitation. We found that the automated tipping-bucket rain gauge needs validation by a manual measurement (Hellmann-type rain gauge), because the data that collected by the automated device will be invalid if the rain intensity is too high.</p><p>In 2017 and 2018, the annual precipitation was distributed evenly, but in the following two years we observed some extremes. In 2019 and<br>2020, the spring was especially dry, the lowest monthly sum was 1.2 mm in 2020 April. 2019 April was similar (19.5 mm), but after the drought<br>period intense rainfall events arrived in May, resulted a monthly total of 214.1 mm. Air temperature and air humidity has not been showed such extremes as the precipitation.</p><p>This study showed that detailed analysis of meteorological parameters is crucial for hydrological modelling data preparation because errors and extreme event can cause serious problems during modelling process and, also in case of evaluation of model results.</p><p>The research has been supported by the Ministry of Agriculture in Hungary.</p>

scholarly journals Development of Heavy Rain Damage Prediction Model Using Machine Learning Based on Big Data

2018 ◽  
Vol 2018 ◽  
pp. 1-11 ◽  
Author(s):  
Changhyun Choi ◽  
Jeonghwan Kim ◽  
Jongsung Kim ◽  
Donghyun Kim ◽  
Younghye Bae ◽  
...  
Keyword(s):  
Machine Learning ◽  
Big Data ◽  
Prediction Model ◽  
Prediction Models ◽  
Meteorological Data ◽  
Heavy Rain ◽  
Machine Learning Techniques ◽  
Damage Prediction ◽  
Explanatory Variables ◽  
The Republic

Prediction models of heavy rain damage using machine learning based on big data were developed for the Seoul Capital Area in the Republic of Korea. We used data on the occurrence of heavy rain damage from 1994 to 2015 as dependent variables and weather big data as explanatory variables. The model was developed by applying machine learning techniques such as decision trees, bagging, random forests, and boosting. As a result of evaluating the prediction performance of each model, the AUC value of the boosting model using meteorological data from the past 1 to 4 days was the highest at 95.87% and was selected as the final model. By using the prediction model developed in this study to predict the occurrence of heavy rain damage for each administrative region, we can greatly reduce the damage through proactive disaster management.

scholarly journals Precision Pulsar Timing with NASA's Deep Space Network

2015 ◽  
Vol 11 (A29B) ◽  
pp. 367-369
Author(s):  
Lawrence Teitelbaum ◽  
Walid Majid ◽  
Manuel M. Franco ◽  
Daniel J. Hoppe ◽  
Shinji Horiuchi ◽  
...  
Keyword(s):  
Low Frequency ◽  
Radio Waves ◽  
Deep Space ◽  
Radio Pulsars ◽  
Deep Space Network ◽  
Space Network ◽  
The Earth ◽  
Pulsar Timing ◽  
Initial Results ◽  
Stable Rotation

AbstractMillisecond pulsars (MSPs) are a class of radio pulsars with extremely stable rotation. Their excellent timing stability can be used to study a wide variety of astrophysical phenomena. In particular, a large sample of these pulsars can be used to detect low-frequency gravitational waves. We have developed a precision pulsar timing backend for the NASA Deep Space Network (DSN), which will allow the use of short gaps in tracking schedules to time pulses from an ensemble of MSPs. The DSN operates clusters of large dish antennas (up to 70-m in diameter), located roughly equidistant around the Earth, for communication and tracking of deep-space spacecraft. The backend system will be capable of removing entirely the dispersive effects of propagation of radio waves through the interstellar medium in real-time. We will describe our development work, initial results, and prospects for future observations over the next few years.

scholarly journals O pensamento de Alberto Torres e a educação rural no Brasil: contribuições ao surgimento do ruralismo pedagógico

1969 ◽  
Author(s):  
Marcelo Augusto Totti ◽  
Vitor Machado
Keyword(s):  
Rural Education ◽  
Natural Resources ◽  
Intellectual Biography ◽  
The Earth ◽  
Sociological Thought ◽  
The Republic ◽  
The Moment ◽  
Education In Brazil

Este texto pretende discorrer sobre o pensamento de Alberto Torres, um dos mais importantes precursores do pensamento sociológico brasileiro, que viveu o momento da implantação da República (1889), dedicando-se a pensar temas relacionados a educação. Por conta da sua biografia política e intelectual, esteve preocupado com problemas que até então a intelectualidade brasileira não se importava em discutir. Tais problemas giravam em torno da defesa do meio ambiente e da necessidade em demonstrar a importância em se educar o homem do campo, para que ele pudesse proteger e resguardar os recursos naturais provenientes da terra. Procuramos demonstrar também que as ideias de Alberto Torres contribuíram de forma significativa para a origem do Ruralismo Pedagógico.Palavras-chave: Alberto Torres. Ruralidade. Ruralismo pedagógico. AbstractThe thought of Alberto Torres and rural education in Brazil: contributions to the emergence of educational ruralismThis paper intends to discuss the thought of Alberto Torres, one of the most important precursors of the Brazilian sociological thought, who lived the moment of the Republic establishment (1889), devoting himself to think about topics related to education. On account of his political and intellectual biography, he was concerned with problems that the Brazilian intellectuality did not care to discuss yet. Suchproblems revolved around the defense of the environment and the need to demonstrate the importance of educating the farmer, so that he could protect and safeguard the earth natural resources. We also demonstrate that the ideas of Alberto Torres contributed significantly to the origin of Educational Ruralism.Keywords: Alberto Torres. Rurality. Educational ruralism. ResumenPensamiento de Alberto Torres y educación rural en Brasil: contribuciones a la aparición de ruralismo educativoEste trabajo tiene como objetivo discutir el pensamiento de Alberto Torres, uno de los precursores más importantes del pensamiento sociológico brasileño, que vivió el momento de la creación de la República (1889) , dedicándose a pensar en temas relacionados con la educación. A causa de su biografía política e intelectual, estaba preocupado con los problemas que hasta ahora la intelectualidad brasileña no le importaba que discutir. Tales problemas voceaban en torno a la defensa del medio ambiente y la necesidad de demostrar la importancia de educar al agricultor, por lo que podrían proteger y preservar los recursos naturales de la tierra. También trató de demostrar que las ideas de Alberto Torres contribuyeron significativamente al origen del Pedagógico ruralismo.Palabras-clave: Alberto Torres. Asuntos rurales. Ruralismo pedagógico. Revisor do inglês: Prof. Ms. Wellington da Silva OliveiraRevisor do espanhol: Prof. Lilian de Souza

scholarly journals Meteorology in field artillery ballistic calculations

2021 ◽  
Vol 2090 (1) ◽  
pp. 012149
Author(s):  
M Mendel
Keyword(s):  
Atmospheric Pressure ◽  
Open Space ◽  
Meteorological Parameters ◽  
Meteorological Data ◽  
Armed Forces ◽  
Weather Conditions ◽  
Atmospheric Conditions ◽  
Area Of Interest ◽  
Single Probe ◽  
Atmospheric Data

Abstract The most important meteorological data are:ambient temperature, precipitation quantity, air humidity, amount and type of clouds, atmospheric pressure, wind direction and speed, visibility, weather phenomena. These coefficients impact the effectiveness of various combat activities, especially those conducted in an open space. Knowledge of future weather conditions is essential for planning the location, calculating times, choice of means, and other aspects relevant to the upcoming operations. Taking weather conditions into account is vital, specifically when it comes to planning combat operations, where the accuracy in cooperation is of paramount importance. Rocket forces and artillery is a particular type of armed forces where weather conditions are critical. The effectiveness of artillery depends on ballistic calculation precision, and so knowledge of atmospheric conditions is fundamental. Atmospheric data are collected from sounding using a single probe attached to a balloon. It is generally known that particular meteorological parameters change in a smooth spatial manner depending on various coefficients. Information about the atmosphere collected by a single probe may be insufficient, due to the possibility of a balloon drifting away from the area of interest, and the calculations are based on data received from its probe. In this paper, I will suggest a method for preparing artillery use meteorologically, which takes into account the distribution of particular meteorological coefficients over a given area.

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