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  <front>
    <journal-meta>
      <journal-title-group>
        <journal-title>Information Control Systems &amp; Technologies, September</journal-title>
      </journal-title-group>
    </journal-meta>
    <article-meta>
      <title-group>
        <article-title>Mining from FITS Files by the Telescope Software</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Sergii Khlamov</string-name>
          <email>sergii.khlamov@gmail.com</email>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Tetiana Trunova</string-name>
          <email>tetiana.trunova@nure.ua</email>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Iryna Tabakova</string-name>
          <email>iryna.tabakova@nure.ua</email>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="editor">
          <string-name>Windows Forms, Microsoft Access</string-name>
        </contrib>
        <aff id="aff0">
          <label>0</label>
          <institution>Kharkiv National University of Radio Electronics</institution>
          ,
          <addr-line>Nauki avenue 14, Kharkiv, 61166</addr-line>
          ,
          <country country="UA">Ukraine</country>
        </aff>
      </contrib-group>
      <pub-date>
        <year>2023</year>
      </pub-date>
      <volume>2</volume>
      <fpage>1</fpage>
      <lpage>23</lpage>
      <abstract>
        <p>In this paper we presented the realization of the data mining approach related to the metadata of astronomical files from the big archives. Each astronomical file has the commonly defined structure, which contains the especial format of the metadata. Such necessary astronomical information, which is required for the proper storing, data mining, processing, analyzing under research. This realization was implemented as software called “Telescope” using the C# programming language, .NET platform, Windows Forms technology and equipped with the MDB database file for Microsoft Access DBMS. The software has two modes: console mode for the automated integration with the processing pipelines and mode with a graphical user interface (GUI) for the visualization of processing and the additional useful features. The Telescope software was designed for mining the big astronomical data from the different archives, parsing the metadata from each astronomical file, and collecting it with the further insertion into the database. Such parsed data were used for the different purposes of the astronomical image processing and machine vision. The Telescope software was developed during research under the CoLiTec project and was tested with the astronomical files from several archives on the different observatories. Also, the implemented and installed on the astronomical image processing pipelines in such observatories. Data mining, big data, metadata, database, image processing, machine vision, C#, .NET, permissions, etc.).</p>
      </abstract>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>1. Introduction</title>
      <p>•
•
•</p>
      <p>Almost all astronomical frames are made by the CCD-camera [1] and can be received from the
different sources: archives, servers, predefined series of frames, Virtual Observatories [2], clusters,
etc. Each software for preparing the astronomical frames creates them as the digital files in the FITS
(Flexible Image Transport System) format [3].</p>
      <p>This format is a digital files format for storing and transferring of their image and metadata
(spreadsheets). Metadata is a kind of data, which provides the information about other data, except the
original data content. There are a lot of different types of metadata, as following [4]:</p>
      <p>Descriptive metadata is an information about the resource, which is used for identification
and includes the elements, like author, title, abstract, and keywords.</p>
      <p>Structural metadata is an information about the data containers and how the objects are
collected. It includes the elements, like relationships, versions, types, etc.
publishing the statistical data.</p>
      <p>Administrative metadata is an information for managing resources (creation date, edition date,
Reference metadata is an information about the static data, references to them, and contents.</p>
      <p>Statistical metadata is an information about the processes for collection, producing, and</p>
      <p>2023 Copyright for this paper by its authors.
• Legal metadata is a legal information about the copyright, creator, and licensing.</p>
      <p>The main purpose of metadata is to provide an information about the different aspects of original
data and to summarize a basic information about it, which make tracking and processing it easier. The
examples of metadata are as following: time and date of data creation, its meaning and purpose,
creator or author, location, file size, used standards, sources, quality, etc.</p>
      <p>For example, the digital image includes the metadata, which describes image size, its color depth,
resolution, creation time and date, exposure time, etc. A metadata of the text document includes an
information about author, processing time of document, short summary, etc. The web pages includes
metadata, which describes a description of page content, and keywords linked to it.</p>
      <p>In astronomy metadata is used for the different image processing and machine vision purposes [5],
like analyzing, acquiring, pre-processing, processing, and extraction of high-dimensional
astronomical information [6].</p>
      <p>Such purposes [7] are focused on but not limited to the following tasks: brightness equalization
and background alignment [8], object’s images detection [9], moving objects detection [10],
astrometry of object’s image [11], photometry of object’s image [12], the estimation of the object’s
image and motion parameters [13], reference objects cataloging [14], objects recognition [15], time
series analysis [16], Wavelet coherence analysis [17] and others.</p>
      <p>There are different types of astrophysical objects that can be detected, like galaxies, stars,
robots [18, 19], drones [20], rockets, satellites [21], and even comets or asteroids [22].</p>
      <p>In this paper we presented a description of the astronomical metadata from the real examples of
CCD-images [23], usage in the data mining approach from the big archives, and its implementation as
a developed Telescope software, which is designed for mining the big astronomical data from the
different archives, parsing the metadata from each astronomical file, and collecting it with the further
insertion into the database.</p>
    </sec>
    <sec id="sec-2">
      <title>2. Big astronomical metadata</title>
      <p>Almost all astronomical frames have a FITS format with standardized file structure and extension. In
the common case the astronomical file extensions are: *.fits, *.FITS, *.fts, *.FTS, *.fit, *.FIT. Such FITS
format is commonly used for the transformation, transferring, and archiving of astronomical data.</p>
      <p>The FITS format was developed by National Aeronautics and Space Administration (NASA) and is
accepted as an international astronomical standard and is used by many astronomical and scientific
organizations, like International Astronomical Union (IAU) [24], and other national and international
organizations that deal with the astronomy or related scientific fields.</p>
      <p>The FITS format is commonly used for the storing the data without the image, like spectrums, photons
list, data cubes or even structured data, such as databases with multiple tables. The FITS format includes
many provisions to describe the photometric and spatial calibration, as well as image metadata.</p>
      <p>The structure of the FITS file consists of a header with metadata and a binary image. The header size is
2880 bytes and contain the list of human readable metadata in fixed string form of 80 symbols. Each string
is an ASCII [25] stroke, which contains the pair with key and value, and have the common form:
“KEYNAME = value / comment string”. Each header block should be ended with the especial key “END”
with the empty value. The example of a header with metadata of the real astronomical FITS file is
presented in the Figure 1.</p>
      <p>There are the minimum list of the required keywords to make the header and the whole FITS file
valid. They are:
• “SIMPLE” (file conforms to FITS standard);
• “BITPIX” (bitrade of FITS file, bits per pixel);
• “NAXIS” (number of axes);
• “NAXIS1” (number of points along axe 1);
• “NAXIS2” (number of points along axe 2);
• “END”.</p>
    </sec>
    <sec id="sec-3">
      <title>3. Telescope software</title>
      <p>Under the research in scope of the CoLiTec project [26] we have developed the Telescope software
for mining the big astronomical data from the different storages and archives, parsing the metadata
from each astronomical file, and collecting it with the further insertion into the database. Such parsed
data were used for the different purposes of the astronomical image processing and machine vision.
3.1.</p>
    </sec>
    <sec id="sec-4">
      <title>Technical implementation</title>
      <p>The Telescope software realized the different data mining tasks, like receiving, storing, selecting,
preprocessing, transforming, useful data extraction, classification, and knowledge discovery in databases
(KDD) [27]. The following stack of technologies were used for the software development: C#
programming language, .NET platform, Windows Forms technology and MDB database file for
Microsoft Access database management system (DBMS). The Windows Forms (WinForms) is an
opensource and free graphical library, which is in a scope of the Microsoft .NET Framework [28] and play
the role as a platform for developing the client applications for desktop, laptop, and tablet PCs.</p>
      <p>As a database the developers have selected a MDB database file as a native format for the
Microsoft Access DBMS with “.mdb” extension [29]. There are different fields located in several
tables of the MDB database file in the Telescope software that represent the necessary for research
metadata of the astronomical file. The list of such fields with their description and types including the
system fields are presented in the Table 1.
• searching for the metadata in a range by the especial criteria in the database (“find [RAfrom]
[RAto] [DEfrom] [DEto] [PathToFile.txt]”);
• exporting the MDB database file to the user’s local folder (“export [PathToFolder]”);
• importing the MDB database file from the user’s local folder (“import [PathToDBFile.mdb]”).
3.3.</p>
    </sec>
    <sec id="sec-5">
      <title>Mode with GUI</title>
      <p>
        The mode with GUI of the Telescope software is designed for the independent big astronomical
metadata preparation. The processing pipeline includes the following steps:
• selecting the work folder including subfolders with the different astronomical FITS files (see
Figure 2);
• recurrency searching for the astronomical FITS files according to the extensions in the work
folder and forming the results list (see Figure 3 (left));
• parsing the astronomical FITS files from the results list, extracting the metadata and insertion
it into the MDB database file (see Figure 3 (right));
• finding the different astronomical metadata in the MDB database file and forming the results list
(see Figure 4 (left));
• converting from arcseconds (angular hours / minutes / seconds) to decimal (
        <xref ref-type="bibr" rid="ref1">1</xref>
        ), (
        <xref ref-type="bibr" rid="ref2">2</xref>
        ) and
vice (3), (4) (see Figure 4 (right)) [11];
• displaying all available astronomical metadata in the MDB database file according to the
results list (see Figure 5);
exporting/importing the MDB database file;
logging the searching, parsing process, error handling.
      </p>
      <p>In general, positional coordinates of objects can be of two types: decimal Cartesian (x and y) in the
image plane and stellar (right ascension RA and declination DE) as angular coordinates in the sky [14].
So, to use the appropriate type of positional coordinates, the following mutual recalculation can be used:
  = ((( 60 +   )/60) +   ) ∗ 15 ;
  = ((  +   )/60) +   ;</p>
      <p>60
  :</p>
      <p>:   = { (
  : 
 :   = { (
(  −   −   )∗ 60
(  −   −   )∗ 60</p>
      <p>( ) 
)(  −   )∗ 60 },
( )</p>
      <p>
        15
)(  −   )∗ 60 } ;
(
        <xref ref-type="bibr" rid="ref1">1</xref>
        )
(
        <xref ref-type="bibr" rid="ref2">2</xref>
        )
(3)
(4)
where d is a decimal value;
      </p>
      <p>H, M, S are the angular hours, minutes, seconds accordingly.
3.4.</p>
    </sec>
    <sec id="sec-6">
      <title>Microsoft Access solution</title>
      <p>The relationships between tables and fields in the Microsoft Access solution of the MDB database
file integrated into the Telescope software is presented in the Figure 6.</p>
      <p>The example of the filled “Fits” table in the MDB database file integrated into the Telescope
software with the real astronomical data is presented in the Figure 7.</p>
      <p>Each value from metadata in header of the FITS file found by the Telescope software was
successfully parsed and filled into the appropriate field in the “Fits” table in the MDB database file for
the further using and processing.</p>
      <p>All interactions between such a database file and the Telescope software are realized by using the
structured query language (SQL) as a programming language for storing and processing information
in a relational database.
3.5.</p>
    </sec>
    <sec id="sec-7">
      <title>Metadata mining algorithm</title>
      <p>The Telescope software implements the following algorithm for astronomical metadata mining.
1. Selecting the work folder including subfolders with the different astronomical FITS or TXT
files.
2. Database import from the pre-filled MDB database file, which was previously exported from
the last session.
3. Recurrency searching for the astronomical FITS or TXT files according to the extensions in
the work folder.
4. Getting access to the astronomical FITS or TXT files (in case when location of big
astronomical data is in the different remote/web archives) and download them.
5. Reading the astronomical FITS or TXT files (for FITS files splitting for two parts: header
with astronomical information and body with image bytes).
6. Parsing the astronomical FITS or TXT files.
7. Astronomical data receiving from the astronomical FITS or TXT files (for FITS files from
header).
8. Astronomical data converting using the different mathematical methods [30] (e.g., positional
coordinates conversion).
9. Astronomical data structurization according to the patterns/classes/clusters based on the
statistical modeling [31].
10. Metadata mining from the astronomical data structure according to the appropriate
parameters/fields/properties.
11. Filling in the appropriate fields and tables in database using the metadata accordingly.
12. Database export to the MDB database file (if needed).</p>
      <p>The metadata mining algorithm implemented in the Telescope software is presented as
UMLdiagram in the Figure 8.</p>
    </sec>
    <sec id="sec-8">
      <title>Real astronomical examples</title>
      <p>The Telescope software was installed in the different observatories (ISON-NM and
ISONKislovodsk observatories, Vihorlat Observatory [8], Mayaki Astronomical Observatory [32, 33]),
astronomical archives [2], and Ukrainian Virtual Observatory (UkrVO) [34].</p>
      <p>The observatory "ISON-NM observatory" has the 0.4 m SANTEL-400AN telescope with CCD-camera
FLI ML09000-65 (3056×3056 pixels, 12 microns).</p>
      <p>The observatory "ISON-Kislovodsk" has the 19.2 cm wide-field GENON (VT-78) telescope with
CCD-camera FLI ML09000-65 (4008×2672 pixels, 9 microns).</p>
      <p>The observatory "Vihorlat Observatory in Humenne" has the Vihorlat National Telescope (VNT) –
Kassegren telescope with 1 m main mirror with focal length 8925 mm and CCD-camera FLI PL1001E
(512×512 pixels).</p>
      <p>The Vihorlat Observatory also has the Celestron C11 telescope – Schmidt-Cassegrain telescope with 28
cm main mirror with focal length of 3060 mm and CCD-camera G2-1600 (resolution 768×512 pixels).</p>
      <p>The Mayaki observing station of "Astronomical Observatory" Research Institute of I. I. Mechnikov
Odessa National University has the 0.48 m AZT-3 telescope – reflector with focal length 2025 mm and
CCD-camera Sony ICX429ALL (resolution 795×596).</p>
      <p>Totally was processed up to 1 million astronomical files both archived and original formed from the
telescopes with a lot of metadata in their headers. The received information was inserted to the database as
a big data and processed by the UkrVO, which also processed a lot of different big astronomical
archives [35] both digital and even plates.</p>
    </sec>
    <sec id="sec-9">
      <title>4. Conclusions</title>
      <p>The Telescope software with the realization of the data mining approach related to the metadata of
astronomical files from the big archives was developed. The Telescope software is implemented using
the C# programming language, .NET platform, Windows Forms technology and equipped with the
MDB database file for the Microsoft Access DBMS. The SQL was used as a programming language
for storing and processing information in a relational database.</p>
      <p>The software has two modes: console mode for the automated integration with the processing
pipelines and mode with a graphical user interface (GUI) for the visualization of processing and the
additional useful features. The Telescope software was designed for mining the big astronomical data
from the different archives, parsing the metadata from each astronomical file, and collecting it with
the further insertion into the database. Such parsed data were used for the different purposes of the
astronomical image processing and even for the Wavelet coherence analysis purposes [36].</p>
      <p>The Telescope software was developed during research under the CoLiTec project [37]. It was
tested with up to 1 million astronomical files from several archives on the different observatories.
Such archives included astronomical files of different formats and types of metadata. All such
metadata was parsed and structured, which given us an opportunity to perform the proper metadata
mining. Such proper metadata was used in the further research and calculations, where the
measurements of each known objects are used to clarify the typical form [38] of image, its orbits,
motion parameters and other important astronomical properties on the long historical period.</p>
      <p>Also, the Telescope software was successfully implemented and installed on the astronomical
image processing pipelines in such observatories.</p>
    </sec>
    <sec id="sec-10">
      <title>5. Acknowledgements</title>
      <p>The authors thank all observatories that provided access to their archives with astronomical data to
conduct the current research and test the developed Telescope software.</p>
    </sec>
    <sec id="sec-11">
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