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Purpose: The goal of the work is to develop a workable technique for fast processing of large arrays of radio astronomy data to search for responses to extragalactic transient events, which a priori should have large dispersion (DM ~ 100÷2000 pc · cm-3). Records of 20-day continuous observations of the sky sphere circumpolar zone with an area of about 8 sq deg and separate files with repeating fast radio burst FRB 121102 were used as a test sample of the technique. Design/methodology/approach: The BSA (Big Scanning Antenna) LPI radio telescope has a multi-beam diagram and is capable of recording daily in the frequency range of 109–111.5 MHz in 96 beams in the declination range from – 8° to +42°. The number of frequency bands varies within 6 to 32 for the time constant varying within 0.1 to 0.0125 s, respectively. In the mode of recording 32 frequency bands with the time constant 0.0125 s, 3.4 GB of data are recorded every hour, 87 GB – daily, and 32 TB – per year. To end of August 2018, about 120 TB of data have been accumulated. Processing this amount of data for a number of scientific problems urgently requires the use of high-performance computing technologies. Findings: The paper proposes two ways to process data: using graphics processors (CPU+GPU, calculation in the C/C++ programming language using OpenCL) and using cluster computing (by using the message passing interface MPI on multiprocessor nodes). To refine the methodology, we use both the processing of pulsar data (using graphic accelerators allows us to increase the processing speed by 2–3 orders of magnitude) and search for responses to extragalactic transient events, which a priori should have large dispersion delays. Examples of such events include fast radio bursts (FRB), responses to gamma radio bursts (GRB) and, finally, possible responses to gravitational events recorded by the LIGO detectors. After processing the polar zone, 697 candidates for pulsed events with high dispersion measures were detected. About half of them is caused by man-made interference, the rest being caused both by the usual interplanetary scintillations of radio sources, and also by the possible soughtfor FRBs. It is still difficult to separate these two classes of events. Processing the data observed in the FRB 121102 zone also indicates the presence of event candidates. The results require more thorough analysis. Сonclusions: After finalizing the high-performance computing methodology, it will allow us to process data observed with the BSA LPI multipath diagram immediately after they are recorded.

Purpose: In the process of astronomical observations vast amounts of data are collected. The BSA (Big Scanning Antenna) used in the study of impulse phenomena, daily logs 87.5 GB of data (32 TB per year). The aim of this work is to develop the web-service which assists the experts with classification of new astronomic observations. The Azure Machine Learning Studio which offers a Deep Neural Network algorithm is used as a tool for web-service developing. Design/methodology/approach: Experts classified 83096 individual observations (on the segment of the study July 2012 – October 2013). Over 89 % of the sample correspond to pulsars, twinkling springs and rapid radiotransmitters, and all other classes of observations belong to hardware failures, interference, the flight of the Earth satellite and aircraft. There were allocated 15 classes of observations. Findings: Such a sample, divided into classes allows using the machine learning algorithms. It has become possible to develop an automated service for short-term/long-term monitoring of various classes of radio sources (including radiotransmitted of different nature), monitoring the Earth’s ionosphere, the interplanetary and the interstellar plasma, search and monitoring of different classes of radio sources. Monitoring in this case refers to the automatic filtering and detection of earlier unclassified impulse phenomena. Currently, for automatic filtering, statistical analysis methods are used. This paper considers an alternative method supposed to be using neural network machine learning algorithm which processes the input into raw data, and after processing by the hidden layer through the output layer determines the class of pulse phenomena. Сonclusions: Creating a neural network model, trained on a sample and classifying earlier unclassified impulse phenomena, is performed using the cloud service Microsoft Azure Machine Learning Studio. The Web service, created based on the aforesaid model, allows classifying both single impulse phenomena in real time (Request / Reply) and data sampling for a certain period (Batch processing).

Purpose: One of the most interesting goals for astronomers are multi-range observations of space objects – not only in different spectral ranges, but also using other sources of information, for example, studies of objects emitting gravitational waves. Design/methodology/approach: The BSA LPI (Big Scanning Antenna of Lebedev Physical Institute) radio telescope has a multi-beam diagram and is capable of recording daily in the frequency range 109–111.5 MHz in 96 beams in the declination range from -8° to +42° daily logs 87.5 GB of data (32 TB per year). The number of frequency bands is within 6 to 32 for the time constant from 0.1 to 0.0125 s. Findings: One of the scientific tasks in processing the data obtained is to search for responses to extragalactic transient events, which a priori should have large dispersion delays (DM ~ 100-2000 pc ·cm -³). Such events include fast radio bursts (FRB) detected so far only at frequencies of 1 GHz and higher, afterglow of nearby cosmic gamma-ray bursts (GRB), in the gamma and X-ray bands, and, finally, possible electromagnetic counterparts of gravitational-wave events recorded in the LIGO-Virgo experiments. The last ones are taken in this paper as a basis for perfection of the technique of searching the like events from the BSA radio data. We provide a brief description of the methodology for finding and estimating the upper limits of possible transient radio sources accompanying the gravitational wave events GW150914, GW151226, LVT151012, and GW170104 recorded by the LIGO detectors. Сonclusions: It is established that nothing brighter than 50000 Jy in the northern hemisphere of the sky at 110 MHz was not observed at the moment of gravitational events. The estimates of energy release in the long-wave radio range are also made: the energy of the low-frequency range is ≤ 1044 erg, while the ratio of the low-frequency range energy to the energy of the gravitational event is ≤10-10.

From 2012 on radio telescope BSA FIAN multi beams diagram was started. It capable at July 2014 daily observing by 96 beams in declination -8 .. 42 degrees in the frequency band 109-111.5 MHz. The number of frequency bands are from 6 to 32, the time constant are from 0.1 to 0.0125 sec. In receiving mode with 32 band (plus one common band) with a time constant of 12.5 ms (80 times per second) respectively produced 33x96x80 four byte real and so daily we produced 87.5 Gbt (yearly to 32 Tbt). These data are enormous opportunities for both short and long-term monitoring of various classes of radio sources (including radio transients) and for space weather and the Earth's ionosphere monitoring, for search for different classes of radio sources, etc. The base aims of our work are: a) to obtain new scientific data on different classes of discrete radio sources, the construction of physical models and their evolution - obtained on the basis of the clock continuous digital sky radio monitoring at frequency 109- 111.5 MHz and cross-analysis of data from third-party reviews on other frequencies; c) launch the streaming data on various types of highperformance computing systems, including to create a public system of distributed computing for thousands of users on the basis of BOINC technology. The BOINC client for astronomical data from the monitoring survey of the big part of entire sky almost have not analogies. We have some first science results (new pulsars, and some new type of radiosources).

On the Pushchino Radio Astronomy Observatory of Lebedev Physical Institute by radio telescope BSA (Big Scanning Antenna) in 2012 started daily multi-beam observations at the frequency range 109- 112 MHz. The number of frequency bands range from 6 to 32, while the time constants range from 0.1 to 0.0125 sec. This data is an enormous opportunity for both short and long-term monitoring of various classes of radio sources (including radio transients), the Earth's ionosphere, interplanetary and interstellar plasma monitoring, search and monitoring for different classes of radio sources, etc. A specialized database was constructed to facilitate the large amount of observational data (http://astro.prao.ru/ cgi/out_img.cgi ). We discuss in this paper method of allocation from the database for impulse data of various types. By using the database allocated 83096 individual impulses in declination from +3 to +42 degrees for July 2012 – October 2013 from pulsars, scintillation sources and so one. In result we constructed homogeneous sample suitable for statistical analyzes.

The Pushchino Observatory of ASC LPI have been developing in some last years database of some astronomical catalogs (Radio Astronomy Data Center - RADC, look on http://astro.prao.ru/db/ and http://observations.prao.ru/). In the database have the most commonly used by radio astronomers data: survey catalogs of radio sources at different radio frequencies (as well as in other spectral bands), catalogs of the major sky objects studied in astronomy etc.

. Now a day the task of comparative analysis of sample sources from different astronomical catalogs is becoming very topical for astronomers. It is useful both for the same spectral range data and for their cross-analysis for different spectral ranges. It is also important, that the real data from astronomical instruments is placed on-line. For the above purposes we are developing a website for the PRAO ASC LPI (www.prao.ru) and, based upon it, the Radio As­tronomy Data Center (RADC). The RADC is a system for storage and processing of radio astronomical data. Here you can find a collection of tools for preparing radio astronomical observations, which includes a base set of main astronomical catalogues useful to radio astronomers, as well as a database of observation results from the Observatory.

Since the work of a unique space radio telescope in the international VLBI project ”Radioastron” extended to 2017 the transmission and storage of large volumes of scientific and telemetry data obtained during the experiments is still remains actual. This project is carried out by theAstroSpaceCenter of Lebedev Physical Institute inMoscow,Russia. It requires us to maintain in operating state the high-speed link to merge into a single LAN buffer data center in Puschino and scientific information center inMoscow. Still relevant the chanal equipment monitoring system, and storage systems, as well as the timely replacement of hardware and software upgrades, backups, and documentation of the network infrastructure.

The need for transmission and storage of large amounts of scientific data in the project space radio telescope ”Radioastron” required us to organize a reliable communication channel between the tracking station in Pushchino and treatment centers in Moscow. Network management data requires us to an integrated approach and covers the organization secure access to manage network devices, timely replacement of equipment and software upgrades, backups, as well as documentation of the network infrastructure. The reliability of the channel is highly dependent on continuous monitoring of network and server equipment and communication lines.

In this paper we report the preliminary results of the total final processing of the entire radio survey observations. They made in 1991-93by LSA of LPI that is full aperture radio telescope in the program survey of the northern sky at a frequency of 102.5 MHz. As a result, the whole sky was covered in declinations and prodused radio sources catalog in -16°≤δ≤+82°.

There is a multiple increase of the volume of scientific data obtained in the course of research each year. Due to this there is a need for continuous improvement, such as data transmission channels and systems for handling and storage of scientific data. For example, data centers show current centers and storage of scientific data and advanced technology in this area, in particular the "cloud" technology. Particular attention is paid to the information infrastructure for data centers storing scientific information.

All main changes in the network of the Pushchino Radio Astronomy Observatory has been related to introduction of the buffer data center in the recent years, upgrading internal and external communication channels and the exploitation of ip-telephony.

From 2012 on radio telescope BSA FIAN multi beams diagram was started. It capable at July 2014 daily observing by 96 beams in declination -8 .. 42 degrees in the frequency band 109-111.5 MHz. The number of frequency bands are from 6 to 32, the time constant are from 0.1 to 0.0125 sec. In receiving mode with 32 band (plus one common band) with a time constant of 12.5 ms (80 times per second) respectively produced 33x96x80 four byte real and so daily we produced 87.5 Gbt (yearly to 32 Tbt). These data are enormous opportunities for both short and long-term monitoring of various classes of radio sources (including radio transients) and for space weather and the Earth's ionosphere monitoring, for search for different classes of radio sources, etc.

Growth of local area network Observatory associated with employee needs to access network resources has led to an increase in the number of computing and network devices. Until recently, we tested performance of these systems excellent manual and most of the problems and faults detected already on the fact the accident occurred. For a small number of network nodes, manual monitoring is not a significant problem, but with increasing the number of nodes troubles hooting becomes a very difficult task for network and system administrators and outage in work of network services Observatory may becomes critical. There fore there was a need to automate the monitoring service network resources and servers.

Buffer data center was created in the territory of the Pushchino Radio Astronomy Observatory three years ago. The necessity of its creation was caused by the high requirements to the speed and quality of the transmission large amounts of scientific and telemetry data received by tracking station RT-22 from the space radio telescope of the international project “Radioastron”. The transfer of this data is carried out over a long distance over100 kmfrom the Pushchino toMoscowcenter of processing and storage ASC FIAN. And now we use the data center as a center of local network of the Observatory.

In modern astronomy the problem of the big data obtained during scientific experiments is very actual. One of the perspective approaches to the solution of the prob­lem of processing of superlarge volumes of experimental data in real time is the use of the technology of cloud computing which assumes ensuring remote dynamic access of users to services, computing resources and appendices on the Internet.

This article shows an overview of the world's major astronomical research programs, for work requiring high-speed data, in particular, examples of major domestic (PRAM ASC LPI) and foreign projects (ALMA, VLA, SDSS, LSST, HESS, MWA, ACT). At the moment the local network to cope with data obtained from experiments load, but for fu­ture projects and the development and modernization of oper­ating projects to the emergence of new technological solutions, due to the increased flow experimental data.

The low-frequency very-long-baseline interferometry network (LFVN) project was started in 1996, having the purpose to arrange the international very-long-baseline interferometry (VLBI) cooperation with participation of former Soviet Union radio telescopes. Currently there are three directions of LFVN development: a Mk 2 subsystem at 92 cm wavelength for solar research, an international S2 ad hoc array at 18 cm for active Galactic nuclei and OH-maser survey, and VLBI radar at 6 cm for investigation of Solar System bodies. 14 VLBI experiments were carried out using various combinations of radio telescopes in Canada, China, England, India, Italy, Japan, Latvia, Poland, Russia, South Africa, Ukraine and USA. The five sessions were processed by the Jet Propulsion Laboratory (California Institute of Technology) Block II and Dominion Radio Astrophysics Laboratory Penticton correlators. The Russian Mk 2 correlator in Nizhny Novgorod is under development. The paper describes the main project milestones, results obtained so far and further plans. [ABSTRACT FROM AUTHOR]