Matematicki Institute SANU

Novi Beograd, Serbia

Matematicki Institute SANU

Novi Beograd, Serbia
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Agency: European Commission | Branch: H2020 | Program: CSA | Phase: ISSI-5-2014 | Award Amount: 3.99M | Year: 2015

NUCLEUS develops, supports and implements inclusive and sustainable approaches to Responsible Research and Innovation within the governance and culture of research organisations in Europe. A major goal of the transdisciplinary project will be to stimulate research and innovation which continuously reflects and responds to societal needs. In order to achieve a multifaceted and cross-cultural New Understanding of Communication, Learning and Engagement in Universities and Scientific Institutions, 26 renowned institutions from 15 countries, among them leading representatives of 14 universities, will collaboratively identify, develop, implement and support inclusive and sustainable approaches to RRI. For a mutual learning and exchange process, the project will reach out beyond the European Research Area by including renowned scientific institutions in China, Russia and South Africa. Within a 4-year timeframe NUCLEUS will systematically uncover and analyse structural and cultural obstacles to RRI in scientific institutions. The partners will collaboratively develop innovative approaches to overcome these barriers. The project is expected to lead to an applicable RRI DNA, providing practical guidelines for higher education institutions and funding agencies across Europe and beyond. This DNA will form the basis for the NUCLEUS Living Network, an alliance to ensure sustainability of the approach beyond the project timeline. By offering new academic insights and practical recommendations derived from 30 RRI test beds, NUCLEUS will contribute to the debate on science policies both on a national and European level, including the future design of HORIZON 2020 and the European Research Area (ERA).

Agency: European Commission | Branch: FP7 | Program: CP-CSA-Infra | Phase: INFRA-2011-1.1.3. | Award Amount: 8.84M | Year: 2012

The Collaborative EuropeaN Digital Archive Infrastructure (CENDARI) will provide and facilitate access to existing archives and resources in Europe for the study of medieval and modern European history through the development of an enquiry environment. This environment will increase access to records of historic importance across the European Research Area, creating a powerful new platform for accessing and investigating historical data in a transnational fashion overcoming the national and institutional data silos that now exist. It will leverage the power of the European infrastructure for Digital Humanities (DARIAH) bringing these technical experts together with leading historians and existing research infrastructures (archives, libraries and individual digital projects) within a programme of technical research informed by cutting edge reflection on the impact of the digital age on scholarly practice. The enquiry environment that is at the heart of this proposal will create new ways to discover meaning, a methodology not just of scale but of kind. It will create tools and workspaces that allow researchers to engage with large data sets via federated multilingual searches across heterogeneous resources while defining workflows enabling the creation of personalized research environments, shared research and teaching spaces, and annotation trails, amongst other features. This will be facilitated by multilingual authority lists of named entities (people, places, events) that will harness user involvement to add intelligence to the system. Moreover, it will develop new visual paradigms for the exploration of patterns generated by the system, from knowledge transfer and dissemination, to language usage and shifts, to the advancement and diffusion of ideas.

Obradovic S.,Matematicki Institute SANU | Tesic D.,AIK Banka | Milanovic D.,Vazduhoplovna Akademija | Zoric A.,Fakultet Tennickih Nauka Kosovska Mitrovica | Perisic D.,Slobomir P University
2012 20th Telecommunications Forum, TELFOR 2012 - Proceedings | Year: 2012

Card payment systems mean three elements: credit cards, ATM and EFT POS terminals. ATM. ATM is primarily a device for predominantly cash withdrawals. The presence of these devices has made the cash available 24/7 but at the same time contributed to the cash still remains the most common payment instrument. There are a lot of manufacturers of software packages necessary for their work. This paper analyzes their representation in Central and Eastern Europe, which includes the Serbian. © 2012 IEEE.

Obradovic S.,Matematicki Institute SANU | Tesic D.,AIK Banka | Milanovic D.,Vazduhoplovna Akademija | Zoric A.,Fakultet Tehnickih Nauka Kosovska Mitrovica | Perisic D.,Slobomir P University
2012 20th Telecommunications Forum, TELFOR 2012 - Proceedings | Year: 2012

Card payment systems mean three elements: credit cards, ATM and EFT POS terminals. ATM. ATM is primarily a device for predominantly cash withdrawals, but also provides many other services to cardholders. Central and Eastern European countries have very uneven level of development of payment card sector. This paper analyzes the state of development of ATM networks in relation to various parameters in the region of Central and Eastern Europe and Serbia. © 2012 IEEE.

Surlan B.,Astronomicky Ustav | Surlan B.,Matematicki Institute SANU | Hamann W.-R.,University of Potsdam | Kubat J.,Astronomicky Ustav | And 2 more authors.
Astronomy and Astrophysics | Year: 2012

Context. The true mass-loss rates from massive stars are important for many branches of astrophysics. For the correct modeling of the resonance lines, which are among the key diagnostics of stellar mass-loss, the stellar wind clumping has been found to be very important. To incorporate clumping into a radiative transfer calculation, three-dimensional (3D) models are required. Various properties of the clumps may have a strong impact on the resonance line formation and, therefore, on the determination of empirical mass-loss rates. Aims. We incorporate the 3D nature of the stellar wind clumping into radiative transfer calculations and investigate how different model parameters influence the resonance line formation. Methods. We develop a full 3D Monte Carlo radiative transfer code for inhomogeneous expanding stellar winds. The number density of clumps follows the mass conservation. For the first time, we use realistic 3D models that describe the dense as well as the tenuous wind components to model the formation of resonance lines in a clumped stellar wind. At the same time, we account for non-monotonic velocity fields. Results. The 3D density and velocity wind inhomogeneities show that there is a very strong impact on the resonance line formation. The different parameters describing the clumping and the velocity field results in different line strengths and profiles. We present a set of representative models for various sets of model parameters and investigate how the resonance lines are affected. Our 3D models show that the line opacity is lower for a larger clump separation and shallower velocity gradients within the clumps. Conclusions. Our model demonstrates that to obtain empirically correct mass-loss rates from the UV resonance lines, the wind clumping and its 3D nature must be taken into account. © 2012 ESO.

Surlan B.,Astronomicky Ustav | Surlan B.,Matematicki Institute SANU | Hamann W.-R.,University of Potsdam | Aret A.,Tartu Observatory | And 4 more authors.
Astronomy and Astrophysics | Year: 2013

Context. Recent studies of O-type stars have demonstrated that discrepant mass-loss rates are obtained when different diagnostic methods are employed. Fitting the unsaturated UV resonance lines (e.g., P v) gives drastically lower values than obtained from the Hα emission. Wind inhomogeneity (so-called "clumping") may be the main cause of this discrepancy. Aims. In a previous paper, we presented 3D Monte-Carlo calculations for the formation of scattering lines in a clumped stellar wind. In the present paper we select five O-type supergiants (from O4 to O7) and test whether the reported discrepancies can be resolved this way. Methods. In the first step, the analyses started with simulating the observed spectra with Potsdam Wolf-Rayet (PoWR) non-LTE model atmospheres. The mass-loss rates are adjusted to fit to the observed Hα emission lines best. For the unsaturated UV resonance lines (i.e., P v) we then applied our 3D Monte-Carlo code, which can account for wind clumps of any optical depths ("macroclumping"), a non-void interclump medium, and a velocity dispersion inside the clumps. The ionization stratifications and underlying photospheric spectra were adopted from the PoWR models. The properties of the wind clumps were constrained by fitting the observed resonance line profiles. Results. Our results show that with the mass-loss rates that fit Hα (and other Balmer and He ii lines), the UV resonance lines (especially the unsaturated doublet of P v) can also be reproduced with no problem when macroclumping is taken into account. There is no need to artificially reduce the mass-loss rates or to assume a subsolar phosphorus abundance or an extremely high clumping factor, unlike what was claimed by other authors. These consistent mass-loss rates are lower by a factor of 1.3 to 2.6, compared to the mass-loss rate recipe from Vink et al. Conclusions. Macroclumping resolves the previously reported discrepancy between Hα and P v mass-loss diagnostics. © 2013 ESO.

Ognjanovic Z.,Matematicki Institute SANU | Doder D.,Masinski Fakultet | Markovic Z.,Matematicki Institute SANU
Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics) | Year: 2011

We introduce a propositional logic whose formulas are built using the language of CTL*, enriched by two types of probability operators: one speaking about probabilities on branches, and one speaking about probabilities of sets of branches with the same initial state. An infinitary axiomatization for the logic, which is shown to be sound and strongly complete with respect to the corresponding class of models, is proposed. © 2011 Springer-Verlag.

Kubat J.,Astronomicky Ustav | Kubatova B.,Astronomicky Ustav | Kubatova B.,Matematicki Institute SANU | Dolezalova B.,Astronomicky Ustav | And 2 more authors.
Astronomy and Astrophysics | Year: 2016

Stable shell stars are ideal objects for studying basic physical principles of the formation of disks in Be stars. If these stars have a close unresolved visual companion, its contribution toward the modelling of the disk cannot be overlooked, as is sometimes done. The study aims to spectroscopically resolve close visual binary Be (shell) star 1 Del, which up to now was only resolved by speckle or micrometric measurements. The integral field spectroscopy obtained by the SINFONI spectrograph at the VLT telescope in the European Southern Observatory (ESO) in the infrared region was used; we supplemented these observations with visual spectroscopy with the Perek Telescope at the Ondrejov Observatory. Spectra of 1 Del were successfully resolved, and, for the first time, spectra of 1 Del B were obtained. We found that 1 DelA is a Be/shell star, while 1 Del B is not an emission-line object. © 2016 ESO.

Borivoje M.,Visoka Tehnicka Skola Strukovnih Studija Nis | Slobodan O.,Matematicki Institute SANU | Nenad N.,Telekom
2012 20th Telecommunications Forum, TELFOR 2012 - Proceedings | Year: 2012

In this paper, we describe the processes in the development of Business Intelligence (BI) business reports that offers the company a precise insight into their operations, monitoring trends and timely (just in time) to assist to management in making important strategic decisions for the further development of the business. © 2012 IEEE.

Jakovljevic N.M.,University of Novi Sad | Popovic B.Z.,University of Novi Sad | Janev M.B.,Matematicki Institute SANU | Delic V.D.,University of Novi Sad
2011 19th Telecommunications Forum, TELFOR 2011 - Proceedings of Papers | Year: 2011

In this paper, the impact of the pitch on the variability of MFCC, and their influence on the performance of the automatic speech recognition system, is analyzed. In case that a speaker has a high pitch, the distance between adjacent harmonics in the spectrum of voiced phonemes is larger, which results in poorer description of the spectral envelope. Additional problem arises in the case that a band-pass filter from the analysis filter bank covers the range between two harmonics, capturing the part of spectrum without energy, which consequently leads to the detection of sudden, non-existing changes in the spectral envelope. The reduction of these variations is analyzed by using a lower number of MFCC, by expending the bandwidths of the band-pass filters from the filter bank at lower frequencies, and also by low-pass filtering of the filter bank output. Some of the results are somewhat different from the similar results presented in the literature, for which the adequate explanations are offered. © 2011 IEEE.

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