The motivations and results from the first 1.5-year period of the project "Wide-field Plate ... more The motivations and results from the first 1.5-year period of the project "Wide-field Plate Database (WFPDB): Development and Access via Internet" (DO-02-273/18.12.2008), approved for funding through a competition held by the Bulgarian National Science Fund in the field of Promotion of Research in Priority Areas, are described. The main direction of the development of the project is digitization and preservation of, and web access to, the astronomical plate archives of the 2-m RCC and the 50/70 cm Schmidt telescopes of the Rozhen National Astronomical Observatory received in the period 1979-1998. The basis of the work is set out in Tsvetkov (2006) [1] and Tsvetkova & Tsvetkov (2006) [2], motivating the project over the past 10 years. The WFPDB (www.wfpdb.org) represents a unique virtual instrument in astronomical research, which allows obtaining information on existing astronomical observations of celestial objects over the past 130 years with the professional astronomical...
This article describes an effort to create a national database of radiation incidents in Bulgaria... more This article describes an effort to create a national database of radiation incidents in Bulgaria. It is intended for use by National Center for Radiobiology and Radiation Protection (NCRRP). The purpose of the database is to store specific description of the radiation incident and to trace the health effect on people who participated in the incident. We show also data from the recent radiation incident in Sliven stored in our database.
In this paper we present tools for helping the process of digi-tization of astronomical photograp... more In this paper we present tools for helping the process of digi-tization of astronomical photographic plates. The requirements of Virtual Observatory presume that any FITS file, which contains a digital image, has to be equipped with a complete header. Wide-Field Plate Database (WFPDB) offers most of the meta-data needed for the creation of FITS header. The header2011 software gives the user an appropriate tool for connecting WFPDB catalogues to digitized plate images. The use of modern scanners sometimes imposes conversion of files from the inner format of the scanner (or driver) into FITS format. The tif2fits software converts VueScan row-tiff format to FITS and also separates plate image and wedge image in case of scanning with grayscale wedge.
An approach to word image matching based on Hausdorff distance is examined for bad quality typewr... more An approach to word image matching based on Hausdorff distance is examined for bad quality typewritten, printed or handwritten Bulgarian documents. A detailed computer experiments were carried out using 49 pages typewritten text, 13 pages printed text and 2 pages of a manuscript. The results of several methods are compared including previously reported methods in the literature.
A digitization project for Bulgarian folk songs Information technologies for presentation of Bulg... more A digitization project for Bulgarian folk songs Information technologies for presentation of Bulgarian folk songs with music, notes and text in a digital library was started last year, joining the efforts of various experts from three institutes of the Bulgarian Academy of Sciences, Sofia University and New Bulgarian University. The research that is carried out under this project is aimed at the development of a technology and corresponding supporting software tools for the creation and usage of heterogeneous institutional digital libraries. The tools will satisfy the needs of the researchers for information technologies in the fields of ethnology, ethnomusicology and folkloristic. In the project frame a technological environment for digitization of notations is created, specially adapted for Bulgarian folk songs. Now a database with notes, lyrics and music is under development. An initial digitization and preservation of the Bulgarian cultural heritage will be carried out by means ...
Here we describe the technology and the experience during the astronomical photographic plate dig... more Here we describe the technology and the experience during the astronomical photographic plate digitization with flatbed EPSON scanners. More than 275000 plates in different observatories in Europe were digitized with such scanners last decade.
We present the Potsdam photographic plate library at the Leibniz Institute for Astrophysics Potsd... more We present the Potsdam photographic plate library at the Leibniz Institute for Astrophysics Potsdam. It includes plate archives, data from plate index catalogues and extracts from astronomical logbooks, as well as digitized plate images and interfaces for accessing all the available information. The plate index catalogues and the digitized images of the Potsdam astronomical photographic plates are prepared according to the standards of the Wide-Field Plate Database and German Astrophysical Virtual Observatory. The high-resolution digitization of the plates (in standardized FITS file format), the low-resolution plate previews (in TIFF and JPEG file format), as well as suitable digitization of the catalogues, logbooks, and relevant scientific research papers (in JPEG and TIFF) are made using commercial flatbed scanners.
We propose a numerical approach for solving systems of nonautonomous ordinary di®erential equatio... more We propose a numerical approach for solving systems of nonautonomous ordinary di®erential equations under suitable assumptions. This approach is based on expansion of the solutions by Volterra series and allows to estimate the accuracy of the approximation. Also we can solve some ordinary di®erential equations for which the classical numerical methods fail.
Abstract: Several recently proposed modifications of Hausdorff distance (HD) are examined with re... more Abstract: Several recently proposed modifications of Hausdorff distance (HD) are examined with respect to word image matching for bad quality typewritten Bulgarian text. The main idea of these approaches presumes that omission of the extreme distances between the points of the compared images eliminates the noise (to some extent) and the algorithms become more robust. A few robust HD measures, namely, censored HD, LTS-HD, and a new binary image comparison method that uses a windowed Hausdorff distance, lie in the base of the computer experiments carried out using 54 pages of typewritten text.
Hausdorff distance (HD) and its modifications provides one of the best approaches for matching of... more Hausdorff distance (HD) and its modifications provides one of the best approaches for matching of binary images. This paper proposes a formalism generalizing almost all of these HD based methods. Numerical experiments for searching words in binary text images are carried out with old Bulgarian typewritten text, printed Bulgarian Chrestomathy from 1884 and Slavonic manuscript from 1574.
ABSTRACT A short discussion of fractal dimensions, the correlation integral method for computing ... more ABSTRACT A short discussion of fractal dimensions, the correlation integral method for computing the spectrum of dimensions and attractor reconstruction is presented. A corresponding software system for IBM-PC is described. The system is used for calculating the spectrum of dimensions of fractal sets, discrete dynamical systems and attractors of differential equations. The results of an analysis of photometric data for the cataclysmic variables TT Ari and KR Aur are presented.
The article describes a test system for assessing students' knowledge of programming. It comb... more The article describes a test system for assessing students' knowledge of programming. It combines the evaluation with elements of the training process and inquiry-based approach in education. Software for the generation, verification and analysis of tests is also presented.
The new interdisciplinary area of Astroinformatics combines scientific knowledge from astronomy a... more The new interdisciplinary area of Astroinformatics combines scientific knowledge from astronomy and Information and Communication Technologies (ICT), based on Internet developments. Recently, four institutes of the Bulgarian Academy of Sciences launched a joint project called ''Astroinformatics'' and aimed at the development of the necessary methods and techniques.
The newly born area of Astroinformatics has emerged as an interdisciplinary area from Astronomy a... more The newly born area of Astroinformatics has emerged as an interdisciplinary area from Astronomy and modern information and communication technologies, based on the modern Internet developments. Recently, four institutes of the Bulgarian Academy of Sciences launched a joint project called “Astroinformatics” and aimed at the development of the necessary methods and techniques. As a truly interdisciplinary area Astroinformatics has arisen from the need of ICT methods for preservation and exploitation of the scientific, cultural and historic heritage of astronomical observations. The Wide-Field Plate Data Base is an ICT project of the Institute of Astronomy, which has been launched in 1991, by the Working Group “Wide-Field Sky Surveys” of the International Astronomic Union (IAU) and is unique by its nature at the international level. So far 150,000 plates have been already digitized through several European research programs. As a result, image-data is collected with about 2TB size and ...
We present the Potsdam photographic plate library at the Leibniz Institute for Astrophysics Potsd... more We present the Potsdam photographic plate library at the Leibniz Institute for Astrophysics Potsdam. It includes plate archives, data from plate index catalogues and extracts from astronomical logbooks, as well as digitized plate images and interfaces for accessing all the available information. The plate index catalogues and the digitized images of the Potsdam astronomical photographic plates are prepared according to the standards of the Wide-Field Plate Database and German Astrophysical Virtual Observatory. The high-resolution digitization of the plates (in standardized FITS file format), the low-resolution plate previews (in TIFF and JPEG file format), as well as suitable digitization of the catalogues, logbooks, and relevant scientific research papers (in JPEG and TIFF) are made using commercial flatbed scanners.
We present a new technology for digitization of astronomical photographic plates. This technology... more We present a new technology for digitization of astronomical photographic plates. This technology is applied to include new plates into the Wide-Field Plate Database (WFPDB, [9]). The need of well-formatted plate metadata put requirements to the acceptance of standard formats for plate/archive description, as well as to the software used for data processing applied to original plate catalogues. The Virtual Observatory [7] requires that the digital image has to be in Flexible Image Transport System (FITS, [6]) file format and equipped with a complete header. The WFPDB offers the most of the metadata needed for creation of the FITS header. The presented here software gives the user appropriate tools for connecting the WFPDB plate catalogues and the plate images. The professional flatbed scanners are the most appropriate devices for scanning astronomical photographic plates. Usually it is imposed to change image files from the inner format of the scanner (or driver) to the standard FIT...
Republican Student Programming Olympiad (Bulgarian Collegiate Programming Contest – BCPC) is a pr... more Republican Student Programming Olympiad (Bulgarian Collegiate Programming Contest – BCPC) is a programming contest for teams of Bulgarian universities have undergraduate programs in informatics. It is held every year on the ACM International Collegiate Programming Contest (ICPC) rules. The Olympiad is an incentive for the best students to improve in subjects algorithms and programming, and it is also an objective criterion for the level of teaching these subjects in higher schools in Bulgaria. Good ranking of the NBU at the Olympics in recent years is a good reason to make a historical overview of the participation and achievements of universities in Bulgaria in this competition also and to pay attention to preparation in the competitive programming of students at NBU.
The motivations and results from the first 1.5-year period of the project "Wide-field Plate ... more The motivations and results from the first 1.5-year period of the project "Wide-field Plate Database (WFPDB): Development and Access via Internet" (DO-02-273/18.12.2008), approved for funding through a competition held by the Bulgarian National Science Fund in the field of Promotion of Research in Priority Areas, are described. The main direction of the development of the project is digitization and preservation of, and web access to, the astronomical plate archives of the 2-m RCC and the 50/70 cm Schmidt telescopes of the Rozhen National Astronomical Observatory received in the period 1979-1998. The basis of the work is set out in Tsvetkov (2006) [1] and Tsvetkova & Tsvetkov (2006) [2], motivating the project over the past 10 years. The WFPDB (www.wfpdb.org) represents a unique virtual instrument in astronomical research, which allows obtaining information on existing astronomical observations of celestial objects over the past 130 years with the professional astronomical...
This article describes an effort to create a national database of radiation incidents in Bulgaria... more This article describes an effort to create a national database of radiation incidents in Bulgaria. It is intended for use by National Center for Radiobiology and Radiation Protection (NCRRP). The purpose of the database is to store specific description of the radiation incident and to trace the health effect on people who participated in the incident. We show also data from the recent radiation incident in Sliven stored in our database.
In this paper we present tools for helping the process of digi-tization of astronomical photograp... more In this paper we present tools for helping the process of digi-tization of astronomical photographic plates. The requirements of Virtual Observatory presume that any FITS file, which contains a digital image, has to be equipped with a complete header. Wide-Field Plate Database (WFPDB) offers most of the meta-data needed for the creation of FITS header. The header2011 software gives the user an appropriate tool for connecting WFPDB catalogues to digitized plate images. The use of modern scanners sometimes imposes conversion of files from the inner format of the scanner (or driver) into FITS format. The tif2fits software converts VueScan row-tiff format to FITS and also separates plate image and wedge image in case of scanning with grayscale wedge.
An approach to word image matching based on Hausdorff distance is examined for bad quality typewr... more An approach to word image matching based on Hausdorff distance is examined for bad quality typewritten, printed or handwritten Bulgarian documents. A detailed computer experiments were carried out using 49 pages typewritten text, 13 pages printed text and 2 pages of a manuscript. The results of several methods are compared including previously reported methods in the literature.
A digitization project for Bulgarian folk songs Information technologies for presentation of Bulg... more A digitization project for Bulgarian folk songs Information technologies for presentation of Bulgarian folk songs with music, notes and text in a digital library was started last year, joining the efforts of various experts from three institutes of the Bulgarian Academy of Sciences, Sofia University and New Bulgarian University. The research that is carried out under this project is aimed at the development of a technology and corresponding supporting software tools for the creation and usage of heterogeneous institutional digital libraries. The tools will satisfy the needs of the researchers for information technologies in the fields of ethnology, ethnomusicology and folkloristic. In the project frame a technological environment for digitization of notations is created, specially adapted for Bulgarian folk songs. Now a database with notes, lyrics and music is under development. An initial digitization and preservation of the Bulgarian cultural heritage will be carried out by means ...
Here we describe the technology and the experience during the astronomical photographic plate dig... more Here we describe the technology and the experience during the astronomical photographic plate digitization with flatbed EPSON scanners. More than 275000 plates in different observatories in Europe were digitized with such scanners last decade.
We present the Potsdam photographic plate library at the Leibniz Institute for Astrophysics Potsd... more We present the Potsdam photographic plate library at the Leibniz Institute for Astrophysics Potsdam. It includes plate archives, data from plate index catalogues and extracts from astronomical logbooks, as well as digitized plate images and interfaces for accessing all the available information. The plate index catalogues and the digitized images of the Potsdam astronomical photographic plates are prepared according to the standards of the Wide-Field Plate Database and German Astrophysical Virtual Observatory. The high-resolution digitization of the plates (in standardized FITS file format), the low-resolution plate previews (in TIFF and JPEG file format), as well as suitable digitization of the catalogues, logbooks, and relevant scientific research papers (in JPEG and TIFF) are made using commercial flatbed scanners.
We propose a numerical approach for solving systems of nonautonomous ordinary di®erential equatio... more We propose a numerical approach for solving systems of nonautonomous ordinary di®erential equations under suitable assumptions. This approach is based on expansion of the solutions by Volterra series and allows to estimate the accuracy of the approximation. Also we can solve some ordinary di®erential equations for which the classical numerical methods fail.
Abstract: Several recently proposed modifications of Hausdorff distance (HD) are examined with re... more Abstract: Several recently proposed modifications of Hausdorff distance (HD) are examined with respect to word image matching for bad quality typewritten Bulgarian text. The main idea of these approaches presumes that omission of the extreme distances between the points of the compared images eliminates the noise (to some extent) and the algorithms become more robust. A few robust HD measures, namely, censored HD, LTS-HD, and a new binary image comparison method that uses a windowed Hausdorff distance, lie in the base of the computer experiments carried out using 54 pages of typewritten text.
Hausdorff distance (HD) and its modifications provides one of the best approaches for matching of... more Hausdorff distance (HD) and its modifications provides one of the best approaches for matching of binary images. This paper proposes a formalism generalizing almost all of these HD based methods. Numerical experiments for searching words in binary text images are carried out with old Bulgarian typewritten text, printed Bulgarian Chrestomathy from 1884 and Slavonic manuscript from 1574.
ABSTRACT A short discussion of fractal dimensions, the correlation integral method for computing ... more ABSTRACT A short discussion of fractal dimensions, the correlation integral method for computing the spectrum of dimensions and attractor reconstruction is presented. A corresponding software system for IBM-PC is described. The system is used for calculating the spectrum of dimensions of fractal sets, discrete dynamical systems and attractors of differential equations. The results of an analysis of photometric data for the cataclysmic variables TT Ari and KR Aur are presented.
The article describes a test system for assessing students' knowledge of programming. It comb... more The article describes a test system for assessing students' knowledge of programming. It combines the evaluation with elements of the training process and inquiry-based approach in education. Software for the generation, verification and analysis of tests is also presented.
The new interdisciplinary area of Astroinformatics combines scientific knowledge from astronomy a... more The new interdisciplinary area of Astroinformatics combines scientific knowledge from astronomy and Information and Communication Technologies (ICT), based on Internet developments. Recently, four institutes of the Bulgarian Academy of Sciences launched a joint project called ''Astroinformatics'' and aimed at the development of the necessary methods and techniques.
The newly born area of Astroinformatics has emerged as an interdisciplinary area from Astronomy a... more The newly born area of Astroinformatics has emerged as an interdisciplinary area from Astronomy and modern information and communication technologies, based on the modern Internet developments. Recently, four institutes of the Bulgarian Academy of Sciences launched a joint project called “Astroinformatics” and aimed at the development of the necessary methods and techniques. As a truly interdisciplinary area Astroinformatics has arisen from the need of ICT methods for preservation and exploitation of the scientific, cultural and historic heritage of astronomical observations. The Wide-Field Plate Data Base is an ICT project of the Institute of Astronomy, which has been launched in 1991, by the Working Group “Wide-Field Sky Surveys” of the International Astronomic Union (IAU) and is unique by its nature at the international level. So far 150,000 plates have been already digitized through several European research programs. As a result, image-data is collected with about 2TB size and ...
We present the Potsdam photographic plate library at the Leibniz Institute for Astrophysics Potsd... more We present the Potsdam photographic plate library at the Leibniz Institute for Astrophysics Potsdam. It includes plate archives, data from plate index catalogues and extracts from astronomical logbooks, as well as digitized plate images and interfaces for accessing all the available information. The plate index catalogues and the digitized images of the Potsdam astronomical photographic plates are prepared according to the standards of the Wide-Field Plate Database and German Astrophysical Virtual Observatory. The high-resolution digitization of the plates (in standardized FITS file format), the low-resolution plate previews (in TIFF and JPEG file format), as well as suitable digitization of the catalogues, logbooks, and relevant scientific research papers (in JPEG and TIFF) are made using commercial flatbed scanners.
We present a new technology for digitization of astronomical photographic plates. This technology... more We present a new technology for digitization of astronomical photographic plates. This technology is applied to include new plates into the Wide-Field Plate Database (WFPDB, [9]). The need of well-formatted plate metadata put requirements to the acceptance of standard formats for plate/archive description, as well as to the software used for data processing applied to original plate catalogues. The Virtual Observatory [7] requires that the digital image has to be in Flexible Image Transport System (FITS, [6]) file format and equipped with a complete header. The WFPDB offers the most of the metadata needed for creation of the FITS header. The presented here software gives the user appropriate tools for connecting the WFPDB plate catalogues and the plate images. The professional flatbed scanners are the most appropriate devices for scanning astronomical photographic plates. Usually it is imposed to change image files from the inner format of the scanner (or driver) to the standard FIT...
Republican Student Programming Olympiad (Bulgarian Collegiate Programming Contest – BCPC) is a pr... more Republican Student Programming Olympiad (Bulgarian Collegiate Programming Contest – BCPC) is a programming contest for teams of Bulgarian universities have undergraduate programs in informatics. It is held every year on the ACM International Collegiate Programming Contest (ICPC) rules. The Olympiad is an incentive for the best students to improve in subjects algorithms and programming, and it is also an objective criterion for the level of teaching these subjects in higher schools in Bulgaria. Good ranking of the NBU at the Olympics in recent years is a good reason to make a historical overview of the participation and achievements of universities in Bulgaria in this competition also and to pay attention to preparation in the competitive programming of students at NBU.
Uploads