Gregor Papa

Prof. Gregor Papa

Jožef Stefan Institute, Computer Systems Department, Slovenia
orcid

Research Focus & Metrics

Academic Career Length

25Years (2002-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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1 January 2019 in Energy
Verified
Journal Article
Open access
RHRok Hribar
Rok Hribar
Primož PotočnikPrimož Potočnik
Primož Potočnik
JŠJurij Šilc
Jurij Šilc
GPGregor Papa
Gregor Papa

25 September 2015 in IEEE Transactions on Energy Conversion
Verified
Journal Article
Closed access
PVPeter Virtic
Peter Virtic
MVMario Vrazic
Mario Vrazic
GPGregor Papa
Gregor Papa
The design optimization of an axial flux permanent magnet synchronous machine with a coreless stator and double external rotor is accomplished by using evolutionary optimization with a genetic algorithm and an analytical evaluation of objective functions. On the basis of eight variable geometry parameters, five objective functions are optimized in order to determine the maximum volume torque density and weight torque density, the minimum volume and weight of permanent magnets per Newton-meter, and the minimum machine price per Newton-meter. Based on the geometric parameters for minimum machine price per Newton-meter, a prototype is built for the rated torque. Optimized and analytically evaluated machine characteristics are validated with a finite-element method (FEM) and the measurements of a prototype. Evolutionary optimization with the analytical evaluation of objective functions significantly shortens the computational time required for design optimization in comparison with the FEM.

16 April 2007 in IEEE Transactions on Systems, Man and Cybernetics, Part C (Applications and Reviews)
Verified
Journal Article
Closed access
Nada LavračNada Lavrač
Nada Lavrač
PLPeter Ljubic
Peter Ljubic
TUTanja Urbancic
Tanja Urbancic
GPGregor Papa
Gregor Papa
MJMitja Jermol
Mitja Jermol
SBStefan Bollhalter
Stefan Bollhalter
The main motivation for organizations and individuals to collaborate is to enable knowledge and resource sharing in order to effectively fulfil a joint business opportunity. This correspondence focuses on virtual organizations (VOs) and virtual teams (VTs), whose strengths lie in the range of competencies of their members, offered jointly through collaboration. One of the difficulties in VO and VT creation is partner selection using partners' mutual trust as one of the selection criteria. This correspondence provides an analysis of trust relationships based on the principal-agent theory, and proposes an approach to hierarchical multiattribute decision-support-based trust estimation applied to a network of collaborating organizations (VO) and a network of collaborating individuals (VT). The correspondence presents two case studies, one using a questionnaire-based approach and the other using automated reputation and collaboration estimation from data gathered by Web crawling

1 June 2020 in Information Fusion
Verified
Journal Article
Open access
MSMonika Simjanoska
Monika Simjanoska
SKStefan Kochev
Stefan Kochev
JTJovan Tanevski
Jovan Tanevski
ABAna Madevska Bogdanova
Ana Madevska Bogdanova
GPGregor Papa
Gregor Papa
TETome Eftimov
Tome Eftimov

13 November 2006 in Applied Intelligence
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Journal Article
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TTTea Tušar
Tea Tušar
PKPeter Korošec
Peter Korošec
GPGregor Papa
Gregor Papa
BFBogdan Filipič
Bogdan Filipič
JŠJurij Šilc
Jurij Šilc

25 April 2021 in Brain Sciences
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Journal Article
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PDF file
TPTamara Jakovljevic Papic
Tamara Jakovljevic Papic
MJMilica Janković
Milica Janković
Andrej SavicAndrej Savic
Andrej Savic
ISIvan Soldatovic
Ivan Soldatovic
GČGordana Čolić
Gordana Čolić
VKVanja Kovic
Vanja Kovic
Reading is one of the essential processes during the maturation of an individual. It is estimated that 5–10% of school-age children are affected by dyslexia, the reading disorder characterised by difficulties in the accuracy or fluency of word recognition. There are many studies which have reported that coloured overlays and background could improve the reading process, especially in children with reading disorders. As dyslexia has neurobiological origins, the aim of the present research was to understand the relationship between physiological parameters and colour modifications in the text and background during reading in children with and without dyslexia. We have measured differences in electroencephalography (EEG), heart rate variability (HRV), electrodermal activities (EDA) and eye movements of the 36 school-age (from 8 to 12 years old) children (18 with dyslexia and 18 of control group) during the reading task in 13 combinations of background and overlay colours. Our findings showed that the dyslexic children have longer reading duration, fixation count, fixation duration average, fixation duration total, and longer saccade count, saccade duration total, and saccade duration average while reading on white and coloured background/overlay. It was found that the turquoise background, turquoise overlay, and yellow background colours are beneficial for dyslexic readers, as they achieved the shortest time duration of the reading tasks when these colours were used. Additionally, dyslexic children have higher values of beta (15–40 Hz) and the broadband EEG (0.5–40 Hz) power while reading in one particular colour (purple), as well as increasing theta range power while reading with the purple overlay. We have observed no significant differences between HRV parameters on white colour, except for single colours (purple, turquoise overlay, and yellow overlay) where the control group showed higher values for mean HR, while dyslexic children scored higher with mean RR. Regarding EDA measure, we found systematically lower values in children with dyslexia in comparison to the control group. Based on the present results, we can conclude that both pastel and intense background/overlays are beneficial for reading of both groups and all sensor modalities could be used to better understand the neurophysiological origins in dyslexic children.