cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
The primordial abundance of 4He: a self-consistent empirical analysis of systematic effects in a large sample of low-metallicity HII regions
Creators: name: Izotov, Y. I.
name: Thuan, T. X.
name: Stasinska, G.
Publisher: name: arXiv
Year: 2007
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: We determine the primordial helium mass fraction Yp using 93 spectra of 86 low-metallicity extragalactic HII regions. This sample constitutes the largest and most homogeneous high-quality data sets in existence for the determination of Yp. For comparison and to improve the statistics in our investigation of systematic effects affecting the Yp determination, we have also considered a sample of 271 low-metallicity HII regions selected from the DR5 of the SDSS. Although this larger sample shows more scatter, it gives results that are consistent at the 2sigma level with our original sample. We have considered known systematic effects which may affect the 4He abundance determination. They include different sets of HeI line emissivities and reddening laws, collisional and fluorescent enhancements of HeI recombination lines, underlying HeI stellar absorption lines, collisional excitation of hydrogen lines, temperature and ionization structure of the HII region, and deviation of HeI and H emission line intensities from case B. However, the most likely value of Yp depends on the adopted set of HeI line emissivities. Using Monte Carlo methods to solve simultaneously the above systematic effects we find a primordial helium mass fraction Yp = 0.2472+/-0.0012 when using the HeI emissivities from Benjamin et al. (1999, 2002) and 0.2516+/-0.0011 when using those from Porter et al. (2005). The first value agrees well with the value given by SBBN theory, while the value obtained with likely more accurate emissivities of Porter et al. (2005) is higher at the 2sigma level. This latter value, if confirmed, would imply slight deviations from SBBN.
description: 56 pages, 15 figures, accepted for publication in the Astrophysical Journal
Emission of Spin-correlated Matter-wave Jets from Spinor Bose-Einstein Condensates
Creators: name: Kim, Kyungtae
name: Hur, Junhyeok
name: Huh, SeungJung
name: Choi, Soonwon
name: Choi, Jae-yoon
Publisher: name: arXiv
Year: 2021
Subjects: subject: Quantum Gases (cond-mat.quant-gas)
subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: We report the observation of matter-wave jet emission in a strongly ferromagnetic spinor Bose-Einstein condensate of $^7$Li atoms. Directional atomic beams with $|{F=1,m_F=1}\rangle$ and $|{F=1,m_F=-1}\rangle$ spin states are generated from $|{F=1,m_F=0}\rangle$ state condensates, or vice versa. This results from collective spin-mixing scattering events, where spontaneously produced pairs of atoms with opposite momentum facilitates additional spin-mixing collisions as they pass through the condensates. The matter-wave jets of different spin states ($|{F=1,m_F=\pm1}\rangle$) can be a macroscopic Einstein-Podolsky-Rosen state with spacelike separation. Its spin-momentum correlations are studied by using the angular correlation function for each spin state. Rotating the spin axis, the inter-spin and intra-spin momentum correlation peaks display a high contrast oscillation, indicating collective coherence of the atomic ensembles. We provide numerical calculations that describe the experimental results at a quantitative level and can identify its entanglement after 100~ms of a long time-of-flight.
description: 13 pages(6 main text, 7 supplemental material), 12 figures
Pit initiation on passivated metal surfaces: crystallographic orientation and environmental effects
Creators: name: Guo, Ruijin
Publisher: name: University of British Columbia
Year: 2008

description: The susceptibility to pitting corrosion of tin and zinc was found to be dependent on the crystallographic orientation of the surface in chloride solutions. For tin single crystals, the(111) face showed the lowest critical pitting potential among five differently oriented surfaces. The critical pitting potential of zinc single crystals decreased with the surface orientation in the following order: (1010) > (1120) > (0001). The critical pitting potentials for zinc and aluminum were found to be lower in chloride solutions than in bromide solutions. The effects of the solution pH, the presence of buffers, and halide ion species on the pitting of polycrystalline nickel were investigated in 1.0 M halide solutions. It was found that the critical pitting potential (Ecp) was independent of the pH of unbuffered solutions in the pH region of 4.5 to 10.5. However, Ecp was greatly increased at pH 12.5, and pitting corrosion was totally retarded at pH 14 in 1.0 M NaC1 solution. The addition of Na2CO3/NaHCO3 orNa3PO4/Na2HPO4 buffer to the pH 10.5 solution raised the critical pitting potential of nickel. Furthermore, Ecp was lower in the chloride solution than in the bromide solution. Using published thermodynamic data for halide complexes, potential-pH (E-pH) and halide concentration - pH (X-pH) diagrams were constructed for H20-halide-metal (Sn, Zn, Al and Ni) systems. With increasing halide concentration, the formation of halide complexes is thermodynamically favoured and the zone of passivity is diminished. These new diagrams are unique and useful in the understanding of pit initiation. A pitting theory is proposed, which emphasizes the change in local solution chemistry and the formation of halide complexes during the pit initiation process. Pits will be nucleated when conditions are met for the formation of stable halide complexes in the local region. This theory successfully accounts for the effects of the solution pH, buffers, halide ions and the crystallographic orientations of single crystals on pitting behavior. It may also explain other aspects such as the effects of temperature, alloying elements, and fluid flow on the pitting corrosion of metals.
Hyperdeterminantal relations among symmetric principal minors
Creators: name: Holtz, Olga
name: Sturmfels, Bernd
Publisher: name: arXiv
Year: 2006
Subjects: subject: Rings and Algebras (math.RA)
subject: Commutative Algebra (math.AC)
subject: FOS: Mathematics
subject: 14M12, 15A15, 15A72, 15A29, 13P10

description: The principal minors of a symmetric $n{\times}n$-matrix form a vector of length $2^n$. We characterize these vectors in terms of algebraic equations derived from the $ 2{\times}2{\times}2$-hyperdeterminant.
description: 12 pages; referee's suggestions incorporated, new section "Invariance and the Quartic Generation Conjecture" added
Ο ρόλος της φυσικής δραστηριότητας στη στυτική δυσλειτουργία σε ασθενείς μέσης ηλικίας με αρτηριακή υπέρταση
Creators: name: Δέρβας, Δημήτρης Ηρακλή
Publisher: name: Aristotle University of Thessaloniki
Year: 2020
Subjects: Υπέρταση
Φυσική δραστηριότητα
Στυτική δυσλειτουργία
Hypertension
Physical activity
Erectile dysfunction

description: Η στυτική δυσλειτουργία εκτιμάται ότι θα φτάσει τις 322 εκατομμύρια περιπτώσεις έως το έτος 2025 και επηρεάζει την ποιότητα ζωής των ασθενών αλλά και των συντρόφων τους. Η στυτική δυσλειουργία αποτελεί δείκτη αυξημένου καρδιαγγειακού κινδύνου, όπως και η υπέρταση. Η αλλαγή του τρόπου ζωής, μεταξύ των άλλων αύξηση της φυσικής δραστηριότητας, είναι η πρώτη οδηγία για την αντιμετώπιση τόσο για της υπέρτασης όσο και για της στυτικής δυσλειτουργίας. Ελέγξαμε κατά πόσο η φυσική δραστηριότητα έχει σχέση με τη στυτική δυσλειτουργία σε υπερτασικούς ασθενείς. Η μελέτη πραγματοποιήθηκε με τη βοήθεια ερωτηματολογίων του IEEF-5 για τη στυτική δυσλειουργία, το IPAQ-27 για τη φυσική δραστηριότητα καθώς επίσης συλλέξαμε στοιχεία βιομετρικά και στοιχεία για την φαρμακευτική αγωγή που ελάμβαναν. Η μελέτη πραγματοποιήθηκε σε πληθυσμό 115 αντρών που προσήλθαν στα περιφερειακά ιατρεία του νομού Κιλκίς. 86 υπερτασικοί άντρες περιλήθφησαν τελικά στην μελέτη. Από την ανάλυση των δεδομένων δε αποδείχτηκε σταστιστικά σημαντική σχέση μεταξύ της στυικής δυσλειτουργίας και της ηλικίας, της παχυσαρκία και της φυσικής δραστηριότητας. Σίγουρα χρείαζεται να γίνουν μελέτες παρέμβασης σε υπερτασικούς ασθενείς για να βγάλουμε ασφαλή συμπεράσματα καθώς επίσης και οι γιατροί της πρωτοβάθμιας να ρωτούν και να ελέγχουν τη σεξουαλική λειουργία των υπερτασικών ασθενών.
description: Erectile dysfunction is estimated to reach 322 million cases by 2025 and affect the quality of life of patients and their partners. Erectile dysfunction is an indicator of increased cardiovascular risk, as is hypertension. Changing lifestyles, among others increasing physical activity, is the first directive to address both hypertension and erectile dysfunction. We tested whether physical activity is related to erectile dysfunction in hypertensive patients. The study was conducted with the help of IEEF-5 questionnaires for erectile dysfunction, IPAQ-27 for physical activity as well as biometrics and medication data collected. The study was conducted on a population of 115 men who came to the regional clinics of Kilkis. 86 hypertensive men were eventually included in the study. Data analysis did not show a statistically significant relationship between erectile dysfunction and age, obesity, and physical activity. Intervention studies in hypertensive patients are certainly needed in order to draw safe conclusions as well as for primary care physicians to question and monitor the sexual function of hypertensive patients.
Spectral sum of current correlators from lattice QCD
Creators: name: Ishikawa, Tsutomu
name: Hashimoto, Shoji
Publisher: name: arXiv
Year: 2021
Subjects: subject: High Energy Physics - Lattice (hep-lat)
subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: We propose a method to use lattice QCD to compute the Borel transform of the vacuum polarization function appearing in the Shifman-Vainshtein-Zakharov QCD sum rule. We construct the spectral sum corresponding to the Borel transform from two-point functions computed on the Euclidean lattice. As a proof of principle, we compute the $s \bar{s}$ correlators at three lattice spacings and take the continuum limit. We confirm that the method yields results that are consistent with the operator product expansion in the large Borel mass region. The method provides a ground on which the OPE analyses can be directly compared with nonperturbative lattice computations.
description: 27 pages, 13 figures, 1 table; data updated, 1 figure added; version to appear in PRD
A proof of concept study for machine learning application to stenosis detection
Creators: name: Jones, Gareth
name: Parr, Jim
name: Nithiarasu, Perumal
name: Pant, Sanjay
Publisher: name: arXiv
Year: 2021
Subjects: subject: Machine Learning (cs.LG)
subject: FOS: Computer and information sciences

description: This proof of concept (PoC) assesses the ability of machine learning (ML) classifiers to predict the presence of a stenosis in a three vessel arterial system consisting of the abdominal aorta bifurcating into the two common iliacs. A virtual patient database (VPD) is created using one-dimensional pulse wave propagation model of haemodynamics. Four different machine learning (ML) methods are used to train and test a series of classifiers -- both binary and multiclass -- to distinguish between healthy and unhealthy virtual patients (VPs) using different combinations of pressure and flow-rate measurements. It is found that the ML classifiers achieve specificities larger than 80% and sensitivities ranging from 50-75%. The most balanced classifier also achieves an area under the receiver operative characteristic curve of 0.75, outperforming approximately 20 methods used in clinical practice, and thus placing the method as moderately accurate. Other important observations from this study are that: i) few measurements can provide similar classification accuracies compared to the case when more/all the measurements are used; ii) some measurements are more informative than others for classification; and iii) a modification of standard methods can result in detection of not only the presence of stenosis, but also the stenosed vessel.
Resonant scattering and recombination of pseudo-degenerate WIMPs
Creators: name: Pospelov, Maxim
name: Ritz, Adam
Publisher: name: arXiv
Year: 2008
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: We consider the direct and indirect detection signatures of WIMPs χ^0 in kinematic regimes with a heavier, but nearly degenerate, charged state χ^{+-}. For small splittings of O(10) MeV, the scattering of WIMPs off nuclei may be dominated by inelastic recombination processes mediated by the formation of (χ^- N) bound states, leading to a distinct signature for direct detection. These cross-sections are bound primarily by limits on the abundance of heavy isotopes, and may be considerably larger than the elastic scattering cross section in more conventional models. If the mass splitting is too large for recombination to occur, there may still be a significant resonant enhancement of loop-induced electromagnetic form-factors of the WIMP, which can enhance the elastic scattering cross-section. We also discuss how this regime affects the annihilation cross-section and indirect detection signatures, and note the possibility of a significant mono-energetic γ-signal, mediated by resonant processes near the (χ^+χ^-) bound state threshold.
description: 22 pages, 6 figures; v2: typos corrected, to appear in Phys. Rev. D
How Large is the "Natural" Magnetic Moment?
Creators: name: Holstein, Barry R.
Publisher: name: arXiv
Year: 2006
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: Nuclear Theory (nucl-th)
subject: FOS: Physical sciences

description: The "natural" magntic moment of a particle of spin S is generally assumed to be that given by the Belinfante conjecture and has the value g=1/S for its gyromagnetic ratio. Thus, for the spin 1/2 electron we find the Dirac value $g_e=2$. However, in the standard model the charged W boson, a spin one particle, is found to have the value $g_{W^+}=2$. We show how this result comes about and argue that the "natural" value for any particle of spin S should be g=2, independent of spin.
description: 23 pages, 2 figures, to be published in the American Journal of Physics
Plasmonic drag photocurrent in graphene at extreme nonlocality
Creators: name: Silkin, Vladimir
name: Svintsov, Dmitry
Publisher: name: arXiv
Year: 2021
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: It is commonly assumed that photocurrent in two-dimensional systems with centrosymmetric lattice is generated at structural inhomogenities, such as p-n junctions. Here, we study an alternative mechanism of photocurrent generation associated with inhomogenity of the driving electromagnetic field, termed as 'plasmonic drag'. It is associated with direct momentum transfer from field to conduction electrons, and can be characterized by a non-local non-linear conductivity $σ^{(2)}({\bf q},ω)$. By constructing a classical kinetic model of non-linear conductivity with full account of non-locality, we show that it is resonantly enhanced for wave phase velocity coinciding with electron Fermi velocity. The enhancement is interpreted as phase locking between electrons and the wave. We discuss a possible experiment where non-uniform field is created by a propagating graphene plasmon, and find an upper limit of the current responsivity vs plasmon velocity. This limit is set by a competition between resonantly growing $σ^{(2)}({\bf q},ω)$ and diverging kinetic energy of electrons as the wave velocity approaches Fermi velocity.
Size reduction of complex networks preserving modularity
Creators: name: Arenas, A.
name: Duch, J.
name: Fernandez, A.
name: Gomez, S.
Publisher: name: arXiv
Year: 2007
Subjects: subject: Computational Physics (physics.comp-ph)
subject: Other Condensed Matter (cond-mat.other)
subject: Discrete Mathematics (cs.DM)
subject: Data Analysis, Statistics and Probability (physics.data-an)
subject: Quantitative Methods (q-bio.QM)
subject: FOS: Physical sciences
subject: FOS: Computer and information sciences
subject: FOS: Biological sciences

description: The ubiquity of modular structure in real-world complex networks is being the focus of attention in many trials to understand the interplay between network topology and functionality. The best approaches to the identification of modular structure are based on the optimization of a quality function known as modularity. However this optimization is a hard task provided that the computational complexity of the problem is in the NP-hard class. Here we propose an exact method for reducing the size of weighted (directed and undirected) complex networks while maintaining invariant its modularity. This size reduction allows the heuristic algorithms that optimize modularity for a better exploration of the modularity landscape. We compare the modularity obtained in several real complex-networks by using the Extremal Optimization algorithm, before and after the size reduction, showing the improvement obtained. We speculate that the proposed analytical size reduction could be extended to an exact coarse graining of the network in the scope of real-space renormalization.
description: 14 pages, 2 figures
Σχολιασμένη διερμηνεία με έμφαση στη διερμηνεία στα όργανα της Ευρωπαϊκής Ένωσης
Creators: name: Καλατζή, Όλγα Λάμπρου
Publisher: name: Aristotle University of Thessaloniki
Year: 2020
Subjects: Διερμηνεία
Ευρωπαϊκή Ένωση
Πολυγλωσσία
Interpreting
European Union
Multilingualism

description: Με τον όρο «διερμηνεία» ορίζεται η μετατροπή μιας σκέψης ή έκφρασης από μια γλώσσα-πηγή σε έκφραση με ανάλογη σημασία σε μια γλώσσα-στόχο, είτε ταυτόχρονα σε "πραγματικό χρόνο" είτε σταδιακά, όταν ο ομιλητής κάνει προσωρινή παύση μετά την ολοκλήρωση μιας ή δύο προτάσεων. Στην Ευρώπη και συγκεκριμένα στην Ευρωπαϊκή Ένωση, η διερμηνεία συμβάλλει στην ομαλή επικοινωνία των κρατών, είκοσι επτά σε αριθμό (λαμβάνοντας υπόψιν την πολύ πρόσφατη αποχώρηση του Ηνωμένου Βασιλείου) με είκοσι τέσσερις επίσημες γλώσσες. Στο πλαίσιο των μεταπτυχιακών σπουδών του διατμηματικού προγράμματος του Αριστοτελείου Πανεπιστημίου Θεσσαλονίκης σχετικά με τη διερμηνεία και τη μετάφραση, οι φοιτητές έπρεπε να κάνουν την πρακτική τους άσκηση κατά τη διάρκεια του τρίτου εξαμήνου. Η φοιτήτρια συμμετείχε στα εξής: σε μία ραδιοφωνική εκπομπή της ΕΡΤ για το 59ο Φεστιβάλ Κινηματογράφου Θεσσαλονίκης, σε ένα διεθνές Συμπόσιο με τίτλο «Αφηγήματα της Μετανάστευσης: Η κοινοτική διερμηνεία ως μέσο εισδοχής» και σε μία προσομοίωση συνεδρίου στο Στρασβούργο με τίτλο «MEUS Strasburg 2019».
description: 'Interpretation' defines the conversion of a thought or expression from a source-language into an expression of a similar meaning to a target-language, either simultaneously in "real time" or gradually, when the speaker pauses after completing one or more sentences. In Europe, and in particular in the European Union, contributes to a better communication among the states with twenty-seven member-states (taking into consideration the recent withdrawal of the United Kingdom from the EU) and twenty-four official languages. During postgraduate studies in the Interdisciplinary Program of the Aristotle University of Thessaloniki on Interpretation and Translation, students ought to do their internship during the third semester. This student of this program, participated in the following: in an ERT broadcast for the 59th Thessaloniki Film Festival, in an international symposium entitled "Migration Narratives: Community Interpretation as a Means of Entry", and in a conference simulation in Strasbourg entitled "MEUS Strasburg 2019".
Μουσείο και ειδικές ομάδες κοινού: η περίπτωση των μουσείων της Θεσσαλονίκης
Creators: name: Κανώτα, Αλεξάνδρα Μιλτιάδη
Publisher: name: Aristotle University of Thessaloniki
Year: 2020
Subjects: Μουσειοπαιδαγωγική
Ποιοτική έρευνα
Ειδικές ομάδες κοινού
Museum education
Qualitative research
Special audience groups

description: Η παρούσα εργασία πραγματεύεται το ζήτημα της μουσειακής εκπαίδευσης και τη σχέση των μουσείων με το κοινό τους. Συγκεκριμένα, επιχειρείται μια έρευνα ως προς τις εκπαιδευτικές δράσεις που προσφέρονται από τα μουσεία της Θεσσαλονίκης και απευθύνονται σε ειδικές ομάδες κοινού. Αρχικά, στο πρώτο μέρος, μελετάται ο κλάδος της μουσειοπαιδαγωγικής και η ανάπτυξή του στην Ελλάδα. Επιπρόσθετα παρουσιάζονται εκπαιδευτικές δράσεις, οι οποίες έχουν υλοποιηθεί στο παρελθόν για ειδικές ομάδες κοινού. Κατόπιν, εξετάζεται το κοινό το οποίο επισκέπτεται τα μουσεία, αλλά και το κοινό, στο οποίο τα μουσεία θέλουν να στοχεύσουν και να εντάξουν στον πυρήνα τους. Παραθέτονται και αναλύονται οι ειδικές ομάδες κοινού και τα κριτήρια τα οποία τις καθιστούν ειδικές. Στο δεύτερο μέρος, παρουσιάζεται η μεθοδολογία της ποιοτικής έρευνας, η οποία διεξήχθη σε 13 μουσεία της Θεσσαλονίκης και παραθέτονται τα αποτελέσματα αυτής, αλλά και διαπιστώσεις.
description: The present paper examines the issue of museum education and the relation between museums and their audience. Specifically, an attempt is being made in order to investigate the educational activities offered by the museums of Thessaloniki, by targeting special audience groups. In the first part, the field of museum education and its development in Greece is being studied. In addition, the educational activities that have previously been implemented for specific groups are being presented. It then examines the audience who visits the museums, but also the audience that museums want to target and integrate into their core. The special audience groups and the criteria which characterize them, are also being presented and analyzed. The second part displays the methodology of the qualitative research, which was conducted by interviewing 13 museums in Thessaloniki while also, presents the results, as well as the findings.
description: Σε συνεργασία με: Παιδαγωγικό Δημοτικής Εκπαίδευσης (Πανεπιστήμιο Δυτικής Μακεδονίας)
The computational complexity of PEPS
Creators: name: Schuch, Norbert
name: Wolf, Michael M.
name: Verstraete, Frank
name: Cirac, J. Ignacio
Publisher: name: arXiv
Year: 2006
Subjects: subject: Quantum Physics (quant-ph)
subject: Other Condensed Matter (cond-mat.other)
subject: FOS: Physical sciences

description: We determine the computational power of preparing Projected Entangled Pair States (PEPS), as well as the complexity of classically simulating them, and generally the complexity of contracting tensor networks. While creating PEPS allows to solve PP problems, the latter two tasks are both proven to be #P-complete. We further show how PEPS can be used to approximate ground states of gapped Hamiltonians, and that creating them is easier than creating arbitrary PEPS. The main tool for our proofs is a duality between PEPS and postselection which allows to use existing results from quantum compexity.
description: 5 pages, 1 figure. Published version, plus a few extras
Εργαστήριο Στατικού Μοντελισμού σε Πολεμικό Μουσείο: Μια Μουσειολογική Αναζήτηση
Creators: name: Βακάσης, Αθανάσιος Γεωργίου
Publisher: name: Aristotle University of Thessaloniki
Year: 2020
Subjects: Στατικός Μοντελισμός
Πολεμικό Μουσείο
Μουσειολογία
Scale Modelling
War Museum
Museology

description: Η παρούσα μελέτη προτείνει την λειτουργία ενός εργαστηρίου στατικού μοντελισμού μέσα σε ένα Πολεμικό Μουσείο (ΠΜ) αφιερωμένο στον Β’ Παγκόσμιο Πόλεμο. Το εργαστήριο αυτό θα είναι ειδικά επανδρωμένο, έτσι ώστε οι επισκέπτες που το επιθυμούν να συμμετέχουν από κοινού με άλλους επισκέπτες και με την βοήθεια εξειδικευμένου προσωπικού (επιμελητές-μοντελιστές, οι οποίοι θα συντονίζουν και θα εμψυχώνουν το γίγνεσθαι του εργαστηρίου) να ολοκληρώνουν έτσι την εμπειρία της μουσειακής τους επίσκεψης. Τα μοντέλα που θα παράγονται στο εργαστήριο θα παραμένουν στο μουσείο, καθώς θα εμπλουτίζουν ένα σχετικό διόραμα, δημιουργώντας κατ’ αυτόν τον τρόπο μια διαλεκτική, δημιουργική μετατόπιση και σχάση μεταξύ του ρόλου τους ως επισκέπτες-θεατές και μετέπειτα ως επισκέπτες-δημιουργοί. Αναμένεται ότι, υπό αυτό το φως, ο στατικός μοντελισμός μπορεί να συμπληρώσει, να εμπλουτίσει, ακόμα και να εμβαθύνει την εμπειρία της μουσειακής επίσκεψης σε ένα ΠΜ του Β’ Παγκοσμίου Πολέμου.
description: This study proposes the establishment of a scale modeling workshop in a War Museum (WM) devoted to World War II. The workshop shall be properly staffed so that visitors wishing to take part along with other visitors and the aid of qualified staff (curator/model-makers, who shall coordinate and animate the workshop’s activities) may this way complete their experience from the visit to the museum. The models constructed in the workshop, shall remain in the museum as they shall enrich a relevant diorama thereby creating a dialectic, creative shift & fission between the visitors’ role as spectators and subsequently as creators. It is expected in this light, that scale modeling may add to, enrich and further deepen the experience of visiting a World War II Museum.
description: Σε συνεργασία με: Παιδαγωγικό Δημοτικής Εκπαίδευσης (Πανεπιστήμιο Δυτικής Μακεδονίας)
Current-induced magnetic vortex core switching in a Permalloy nanodisk
Creators: name: Liu, Y.
name: Gliga, S.
name: Hertel, R.
name: Schneider, C. M.
Publisher: name: arXiv
Year: 2007
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: We report on the switching of a magnetic vortex core in a sub-micron Permalloy disk, induced by a short current pulse applied in the film plane. Micromagnetic simulations including the adiabatic and non-adiabatic spin-torque terms are used to investigate the current-driven magnetization dynamics. We predict that a core reversal can be triggered by current bursts a tenth of a nanosecond long. The vortex core reversal process is found to be the same as when an external field pulse is applied. The control of a vortex core's orientation using current pulses introduces the technologically relevant possibility to address individual nanomagnets within dense arrays.
description: 3 pages, 3 figures
Η εκπαιδευτική πολιτική της Εφορείας Αρχαιοτήτων Ιωαννίνων για το χώρο του κάστρου: αποτίμηση και προτάσεις για επέκταση σε διαφορετικές ομάδες κοινού
Creators: name: Παπαχριστοπούλου, Χαραλαμπία Ηλία
Publisher: name: Aristotle University of Thessaloniki
Year: 2020
Subjects: Εκπαιδευτική πολιτική
Κάστρο Ιωαννίνων
Εκπαιδευτικά προγράμματα
Educational policy
Castle of Ioannina
Educational programs

description: Το θέμα της παρούσας εργασίας είναι η παρουσίαση και η αποτίμηση της εκπαιδευτικής πολιτικής του Βυζαντινού μουσείου Ιωαννίνων καθώς και οι προτάσεις για επέκτασή της σε διαφορετικές ομάδες κοινού. Αρχικά αναπτύσσεται ένα συνεκτικό θεωρητικό κεφάλαιο για την εκπαιδευτική πολιτική των μουσείων στον 21ο αιώνα στο πλαίσιο της Νέας Μουσειολογίας. Η εργασία συνεχίζει με την παρουσίαση και αξιολόγηση της μέχρι τώρα εκπαιδευτικής πολιτικής που ακολουθεί το Βυζαντινό μουσείο Ιωαννίνων( ΕΦΑ Ιωαννίνων). Ακόμα γίνονται προτάσεις εξέλιξης της επικοινωνιακής πολιτικής για το χώρο του κάστρου των Ιωαννίνων και εκπαιδευτικών προγραμμάτων για διάφορες ομάδες κοινού, όπως οι έφηβοι, οι ηλικιωμένοι, οι οικογένειες με παιδιά και άτομα με ειδικές ανάγκες. Στην εργασία περιλαμβάνονται και τα δύο εκπαιδευτικά προγράμματα, τα οποία σχεδιάστηκαν και υλοποιήθηκαν στο χώρο του Βυζαντινού μουσείου και του κάστρου των Ιωαννίνων, στο πλαίσιο της εκπόνησης της πρακτικής μου εργασίας. Τέλος, γίνεται μία αξιολόγηση των προγραμμάτων αυτών με βάση τα αποτελέσματα που είχαμε μετά την εφαρμογή τους.
description: The subject of this paper is the presentation and evaluation of the educational policy of the Byzantine Museum of Ioannina as well as the proposals for its expansion to different audiences. At first, a theoretical chapter is developed for educational policy of museums in the 21st century in the context of New Museology. The study continues with the presentation and evaluation of the educational policy pursued so far by the Byzantine Museum of Ioannina. There are also proposals for the development of communication policy for the area of the castle of Ioannina and educational programs for various groups of audiences, such as teenagers, the elderly, families with children and people with disabilities. The study includes both educational programs, which were designed and implemented in the area of the Byzantine Museum and the castle of Ioannina, in the context of my internship. Finally, there is a review of these programs based on the results we had after implemented.
description: Σε συνεργασία με: Παιδαγωγικό Δημοτικής Εκπαίδευσης (Πανεπιστήμιο Δυτικής Μακεδονίας)
Resonant forcing of nonlinear systems of differential equations
Creators: name: Gintautas, Vadas
name: Hubler, Alfred W.
Publisher: name: arXiv
Year: 2008
Subjects: subject: Chaotic Dynamics (nlin.CD)
subject: FOS: Physical sciences

description: We study resonances of nonlinear systems of differential equations, including but not limited to the equations of motion of a particle moving in a potential. We use the calculus of variations to determine the minimal additive forcing function that induces a desired terminal response, such as an energy in the case of a physical system. We include the additional constraint that only select degrees of freedom be forced, corresponding to a very general class of problems in which not all of the degrees of freedom in an experimental system are accessible to forcing. We find that certain Lagrange multipliers take on a fundamental physical role as the effective forcing experienced by the degrees of freedom which are not forced directly. Furthermore, we find that the product of the displacement of nearby trajectories and the effective total forcing function is a conserved quantity. We demonstrate the efficacy of this methodology with several examples.
description: 9 pages, 3 figures
Η Καπερναούμ της Γαλιλαίας στη δημόσια δράση του Ιησού. Οι γραπτές και αρχαιολογικές πηγές
Creators: name: Παπαδάκη, Αικατερίνη Γεωργίου
Publisher: name: Aristotle University of Thessaloniki
Year: 2020
Subjects: Καπερναούμ
Ευαγγέλια
Αρχαιολογία
Capernaum
Gospels
Archaeology

description: Σκοπός της διπλωματικής εργασίας ήταν η προσέγγιση της περιοχής της Καπερναούμ στη δημόσια δράση του Ιησού σε συνδυασμό με γραπτές και αρχαιολογικές πηγές. Αρχικά, αφού παρουσιάστηκαν οι γραπτές πηγές ( ονομασία, τοποθεσία, ιστορική αναδρομή), στη συνέχεια ασχοληθήκαμε με τις διηγήσεις της δημόσια δράσης του Ιησού στη Καπερναούμ, σε όλα τα ευαγγέλια. Χρησιμοποιώντας την ιστορικο κριτική μέθοδο σε συνδυασμό με την αρχαιολογία παρουσιάσαμε στο τέλος τις αρχαιολογικά ευρήματα που βρέθηκαν στην Καπερναούμ.
description: The aim of the present thesis was to approximate the Capernaum area to Jesus’ public action in combination with written and archaeological sources. Initially after the written sources (nominal, location, historical retrospective) were presented, we then dealt with the narrators of Jesus’ public action in Capernaum, in all the gospels. Using the historical criticism method in combination with archaeology, we finally presented the archaeological findings found in Capernaum .
Shapes and energies of icosahedral fullerenes: Onset of ridge sharpening transition
Creators: name: Siber, A.
Publisher: name: arXiv
Year: 2006
Subjects: subject: Other Condensed Matter (cond-mat.other)
subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: Shapes and energies of icosahedral fullerenes are studied on an atomically detailed level. The numerical results based on the effective binary carbon-carbon potential are related to the theory of elasticity of crystalline membranes with disclinations. Depending on fullerene size, three regimes are clearly identified, each of them characterized by different geometrical properties of the fullerene shape. For extremely large fullerenes (more than about 500000 atoms), transition of fullerene shapes to their asymptotic limit is detected, in agreement with previous predictions based on generic elastic description of icosahedral shells. Quantum effects related to delocalized electrons on the fullerene surface are discussed and a simple model introduced to study such effects suggests that the transition survives even in more general circumstances.
description: Revised to discuss the effects of electronic delocalization on the ridge-sharpening transition. Submitted
Particle growing mechanisms in Ag-ZrO2 and Au-ZrO2 granular films obtained by pulsed laser deposition
Creators: name: Konstantinovic, Zorica
name: del Muro, Montserrat Garcia
name: Varela, Manuel
name: Batlle, Xavier
name: Labarta, Amilcar
Publisher: name: arXiv
Year: 2006
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: Disordered Systems and Neural Networks (cond-mat.dis-nn)
subject: FOS: Physical sciences

description: Thin films consisting of Ag and Au nanoparticles embedded in amorphous ZrO2 matrix were grown by pulsed laser deposition in a wide range of metal volume concentrations in the dielectric regime (0.08
description: 6 figures
What's wrong with this rebuttal?
Creators: name: Kracklauer, A. F.
Publisher: name: arXiv
Year: 2006
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: A recent rebuttal to criticism of Bell's analysis is shown to be defective by fault of failure to consider all hypothetical conditions input into the derivation of Bell Inequalitites.
description: 2 pages
A Magnetic Alpha-Omega Dynamo in Active Galactic Nuclei Disks: II. Magnetic Field Generation, Theories and Simulations
Creators: name: Pariev, Vladimir I.
name: Colgate, Stirling A.
name: Finn, John M.
Publisher: name: arXiv
Year: 2006
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: It is shown that a dynamo can operate in an Active Galactic Nuclei accretion disk due to the Keplerian shear and due to the helical motions of expanding and twisting plumes of plasma heated by many star passages through the disk. Each plume rotates a fraction of the toroidal flux into poloidal flux, always in the same direction, through a finite angle, and proportional to its diameter. The predicted growth rate of poloidal magnetic flux, based upon two analytic approaches and numerical simulations, leads to a rapid exponentiation of a seed field, \sim 0.1 to \sim 0.01 per Keplerian period of the inner part of the disk. The initial value of the seed field may therefore be arbitrarily small yet reach, through dynamo gain, saturation very early in the disk history. Because of tidal disruption of stars close to the black hole, the maximum growth rate occurs at a radius of about 100 gravitational radii from the central object. The generated mean magnetic field, a quadrupole field, has predominantly even parity so that the radial component does not reverse sign across the midplane. The linear growth is predicted to be the same by each of the following three theoretical analyses: the flux conversion model, the mean field approach, and numerical modeling. The common feature is the conducting fluid flow, considered in companion Paper I (Pariev and Colgate 2006) where two coherent large scale flows occur naturally: the differential winding of Keplerian motion and differential rotation of expanding plumes.
description: 70 pages, 21 figure, accepted for publication in ApJ
Topics in Leptogenesis
Creators: name: Nardi, Enrico
Publisher: name: arXiv
Year: 2007
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: Baryogenesis via leptogenesis provides an appealing mechanism to explain the observed baryon asymmetry of the Universe. Recent refinements in the understanding of the dynamics of leptogenesis include detailed studies of the effects of lepton flavors and of the role possibly played by the lepton asymmetries generated in the decays of the heavier singlet neutrinos $N_{2,3}$. In this talk I present a short review of these recent developments in the theory of leptogenesis.
description: 8 pages, 2 figures. To appear in the proceedings of 6th Latin American Symposium on High Energy Physics (VI-SILAFAE), Puerto Vallarta, Mexico, November 1-8, 2006
Idealist-Ontological Metaverse A XChronos Proposal for Digital Spaces Anchored in Consciousness.
Creators: name: Souza Silva, Jaconaazar
Publisher: name: Zenodo
Year: 2025
Subjects: XChronos
Idealism
Ontological Metaverse
Bernardo Kastrup
Symbolic Time
Chronons
Hexachronons
Hexa (ɧ)
Consciousness-Based Design
Philosophy of Mind
Post-Material Economy
Digital Presence
Synchronicity
Experiential Value
Quantum Metaphysics
Virtual Ontology

description: This essay presents a conceptual proposal for an Idealist-Ontological Metaverse grounded in the symbolic time architecture of the XChronos model. Drawing inspiration from Bernardo Kastrup's analytical idealism, it explores how digital environments — particularly metaverses — can be designed not merely as immersive simulations, but as symbolic extensions of consciousness. In this vision, time is not measured by mechanical clocks but by the depth of presence, using units such as Chronons and Hexachronons, and a symbolic currency called Hexa (ɧ). This framework suggests a new kind of virtual economy and experience — one rooted in meaning, synchronicity, and phenomenological richness — rather than distraction and digital noise.
Το ζήτημα των Τσάμηδων στο πλαίσιο των ελληνοαλβανικών σχέσεων και της ιταλικής βαλκανικής πολιτικής κατά τον Μεσοπόλεμο
Creators: name: Συροπλάκης, Αθανάσιος Αριστοτέλη
Publisher: name: Aristotle University of Thessaloniki
Year: 2020
Subjects: Τσάμηδες
Ελληνοαλβανικές σχέσεις
Ιταλική βαλκανική πολιτική
Chams
Greek-Albanian Relations
Italy’s Balkan Policy

description: Κεντρικό θέμα της μεταπτυχιακής διπλωματικής εργασίας είναι η εξέταση του ζητήματος των Τσάμηδων και της επίδρασής του στις ελληνοαλβανικές σχέσεις, καθώς και η διερεύνηση του ρόλου της Ιταλίας στη διαμόρφωση της πολιτικής της Αλβανίας αναφορικά με το ζήτημα κατά τη διάρκεια του Μεσοπολέμου. Παρότι η οργάνωση της εργασίας είναι θεματική, το περιεχόμενο των θεματικών ενοτήτων παρουσιάζεται σε μία χρονική αλληλουχία. Στην πρώτη ενότητα εξετάζονται η ταυτότητα των Τσάμηδων κατά τα πρώτα έτη του Μεσοπολέμου, η εξέλιξή της από θρησκευτική σε εθνική καθώς και οι παράγοντες οι οποίοι επέδρασαν καταλυτικά σε αυτήν τη διαδικασία. Στη δεύτερη ενότητα πραγματοποιείται εκτενής ανάλυση των κτηματικών υποθέσεων των Τσάμηδων και των γαιοκτημόνων αλβανικής υπηκοότητας. Στην τελευταία ενότητα μελετώνται η εκπαίδευση των Τσάμηδων και η διαμόρφωση της πολιτικής του ελληνικού κράτους απέναντι στη μειονότητα από το 1926 μέχρι το 1940. Η εργασία βασίζεται κατά κύριο λόγο σε αδημοσίευτο αρχειακό υλικό του ελληνικού Υπουργείου Εξωτερικών.
description: The purpose of this dissertation is to examine the Chams Issue, its impact on Greek-Albanian diplomatic relations, as well as to investigate Italy’s role in shaping Albania’s policy in connection to the Issue during the Interwar period. Although the structure of the study is thematic, the content of the thematic sections is presented in a chronological sequence. In the first chapter, we investigate the identity of Chams during the first years of the Interwar period, its evolution from religious to national, as well as the factors that influenced this process dramatically. In the second chapter, we present an extensive analysis of the estate affairs of Chams and the landowners of Albanian nationality. In the last chapter, we examine the education of Chams and the formation of the Greek state’s policy towards the minority from 1926 to 1940. The dissertation is mainly based on unpublished archival material of the Greek Ministry of Foreign Affairs.
Second-order fast-slow dynamics of non-ergodic Hamiltonian systems: Thermodynamic interpretation and simulation
Creators: name: Klar, Matthias
name: Matthies, Karsten
name: Reina, Celia
name: Zimmer, Johannes
Publisher: name: arXiv
Year: 2021
Subjects: subject: Mathematical Physics (math-ph)
subject: Classical Analysis and ODEs (math.CA)
subject: Dynamical Systems (math.DS)
subject: FOS: Physical sciences
subject: FOS: Mathematics

description: A class of fast-slow Hamiltonian systems with potential $U_\varepsilon$ describing the interaction of non-ergodic fast and slow degrees of freedom is studied. The parameter $\varepsilon$ indicates the typical timescale ratio of the fast and slow degrees of freedom. It is known that the Hamiltonian system converges for $\varepsilon\to0$ to a homogenised Hamiltonian system. We study the situation where $\varepsilon$ is small but positive. First, we rigorously derive the second-order corrections to the homogenised (slow) degrees of freedom. They can be decomposed into explicitly given terms that oscillate rapidly around zero and terms that trace the average motion of the corrections, which are given as the solution to an inhomogeneous linear system of differential equations. Then, we analyse the energy of the fast degrees of freedom expanded to second-order from a thermodynamic point of view. In particular, we define and expand to second-order a temperature, an entropy and external forces and show that they satisfy to leading-order, as well as on average to second-order, thermodynamic energy relations akin to the first and second law of thermodynamics. Finally, we analyse for a specific fast-slow Hamiltonian system the second-order asymptotic expansion of the slow degrees of freedom from a numerical point of view. Their approximation quality for short and long time frames and their total computation time are compared with those of the solution to the original fast-slow Hamiltonian system of similar accuracy.
Mixtures in non stable Levy processes
Creators: name: Petroni, Nicola Cufaro
Publisher: name: arXiv
Year: 2007
Subjects: subject: Probability (math.PR)
subject: Statistical Mechanics (cond-mat.stat-mech)
subject: Accelerator Physics (physics.acc-ph)
subject: Computational Finance (q-fin.CP)
subject: FOS: Mathematics
subject: FOS: Physical sciences
subject: FOS: Economics and business
subject: 60E07, 60G10, 60G51, 60J75

description: We analyze the Levy processes produced by means of two interconnected classes of non stable, infinitely divisible distribution: the Variance Gamma and the Student laws. While the Variance Gamma family is closed under convolution, the Student one is not: this makes its time evolution more complicated. We prove that -- at least for one particular type of Student processes suggested by recent empirical results, and for integral times -- the distribution of the process is a mixture of other types of Student distributions, randomized by means of a new probability distribution. The mixture is such that along the time the asymptotic behavior of the probability density functions always coincide with that of the generating Student law. We put forward the conjecture that this can be a general feature of the Student processes. We finally analyze the Ornstein--Uhlenbeck process driven by our Levy noises and show a few simulation of it.
description: 28 pages, 3 figures, to be published in J. Phys. A: Math. Gen
On the Philosophical, Cognitive and Mathematical Foundations of Symbiotic Autonomous Systems (SAS)
Creators: name: Wang, Yingxu
name: Karray, Fakhri
name: Kwong, Sam
name: Plataniotis, Konstantinos N.
name: Leung, Henry
name: Hou, Ming
name: Tunstel, Edward
name: Rudas, Imre J.
name: Trajkovic, Ljiljana
name: Kaynak, Okyay
name: Kacprzyk, Janusz
name: Zhou, Mengchu
name: Smith, Michael H.
name: Chen, Philip
name: Patel, Shushma
Publisher: name: arXiv
Year: 2021
Subjects: subject: Artificial Intelligence (cs.AI)
subject: FOS: Computer and information sciences

description: Symbiotic Autonomous Systems (SAS) are advanced intelligent and cognitive systems exhibiting autonomous collective intelligence enabled by coherent symbiosis of human-machine interactions in hybrid societies. Basic research in the emerging field of SAS has triggered advanced general AI technologies functioning without human intervention or hybrid symbiotic systems synergizing humans and intelligent machines into coherent cognitive systems. This work presents a theoretical framework of SAS underpinned by the latest advances in intelligence, cognition, computer, and system sciences. SAS are characterized by the composition of autonomous and symbiotic systems that adopt bio-brain-social-inspired and heterogeneously synergized structures and autonomous behaviors. This paper explores their cognitive and mathematical foundations. The challenge to seamless human-machine interactions in a hybrid environment is addressed. SAS-based collective intelligence is explored in order to augment human capability by autonomous machine intelligence towards the next generation of general AI, autonomous computers, and trustworthy mission-critical intelligent systems. Emerging paradigms and engineering applications of SAS are elaborated via an autonomous knowledge learning system that symbiotically works between humans and cognitive robots.
description: Accepted by Phil. Trans. Royal Society (A): Math, Phys & Engg Sci., 379(219x), 2021, Oxford, UK
Two populations of metal-free stars in the early Universe
Creators: name: Greif, Thomas H.
name: Bromm, Volker
Publisher: name: arXiv
Year: 2006
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: We construct star formation histories at redshifts z > 5 for two physically distinct populations of primordial, metal-free stars, motivated by theoretical and observational arguments that have hinted towards the existence of an intermediate stellar generation between Population III and Population I/II. Taking into account the cosmological parameters as recently revised by WMAP after three years of operation, we determine self-consistent reionization histories and discuss the resulting chemical enrichment from these early stellar generations. We find that the bulk of ionizing photons and heavy elements produced at high redshifts must have originated in Population II.5 stars, which formed out of primordial gas in haloes with virial temperatures >= 10^4 K, and had typical masses >= 10 M_sun. Classical Population III stars, formed in minihaloes and having masses >= 100 M_sun, on the other hand, had only a minor impact on reionization and early metal enrichment. Specifically, we find that only 10 per cent by mass of metal-free star formation went into Population III.
description: 12 pages, 7 figures, 1 table, published in MNRAS
Study of anomaly detection techniques in exchange rate time series data
Creators: name: Μπάμπης, Νικόλαος Ευθυμίου
Publisher: name: Aristotle University of Thessaloniki
Year: 2020
Subjects: Ανίχνευση ανωμαλιών
Αλγόριθμος απόστασης
Αλγόριθμος πυκνότητας
Outlier detection
Distance based
Density based

description: Time series outlier detection has been attracting a lot of attention in research and application. In this diploma thesis, we introduce the problem of detecting outliers in exchange rate data set based on distance and density methods. We study the problem using Euclidean distance in distance-based algorithm and Local Outlier Factor (LOF) for density-based approach. The problem is analyzed with big data terms. So, the usage of Apache Spark Framework for the implementation was a key parameter of the thesis. The overall aim of the diploma thesis is to examine anomaly detection in time series with big data conditions.
description: Η ανίχνευση ανωμαλιών σε δεδομένα χρονοσειράς προσελκύει την προσοχή στην έρευνα και την εφαρμογή. Σε αυτή τη διπλωματική εργασία, παρουσιάζουμε το πρόβλημα ανίχνευσης ανωμαλιών σε δεδομένα συναλλαγματικής ισοτιμίας με βάσει τις μεθόδους απόστασης και πυκνότητας. Μελετάμε το πρόβλημα χρησιμοποιώντας την ευκλείδεια απόσταση σε αλγόριθμο με βάση την απόσταση και το Local Outlier Factor (LOF) για την προσέγγιση με βάση την πυκνότητα. Το πρόβλημα αναλύεται με όρους μεγάλων δεδομένων. Έτσι, η χρήση του Apache Spark Framework για την υλοποίηση ήταν μια βασική παράμετρος της διατριβής. Ο γενικός στόχος της διπλωματικής εργασίας είναι να εξετάσει την ανίχνευση ανωμαλιών σε χρονοσειρές με συνθήκες μεγάλων δεδομένων.