cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Multiband-Driven Superfluid-Insulator Transition of Fermionic Atoms in Optical Lattices: A Dynamical Mean-Field-Theory Study
Creators: name: Higashiyama, Takuji
name: Inaba, Kensuke
name: Suga, Sei-ichiro
Publisher: name: arXiv
Year: 2008
Subjects: subject: Other Condensed Matter (cond-mat.other)
subject: Superconductivity (cond-mat.supr-con)
subject: FOS: Physical sciences

description: The superfluid-insulator transitions of the fermionic atoms in optical lattices are investigated by the two-site dynamical mean-field theory. It is shown that the Mott transition occurs as a result of the multiband effects. The quasiparticle weight in the superfluid state decreases significantly, as the system approaches the Mott transition point. By changing the interaction and the orbital splitting, we obtain the phase diagram at half filling. The numerical results are discussed in comparison with the effective boson model.
description: 4 pages, 3 figures, Phys. Rev. A 77, 043624 (2008)
Welsh Wreck Web Research Project (North Cardigan Bay). On-line research into the wreck of the: Zebulon
Creators: name: Perks, Graeme
Publisher: name: Archaeology Data Service
Year: 2024

description: Welsh Wreck Web Research Project unpublished report series, 1
description: Research report on the Zebulon, grounded on St Patricks causeway (Sarn Badrig), Cardigan Bay in 1835.
Psychosocial resilience in adults with chronic post-stroke communication disorders: A scoping review protocol
Creators: name: Jones, Jacqueline Nicole
name: Pyche, Courtney
name: Morgan-Daniel, Jane
Publisher: name: OSF Registries
Year: 2024
Subjects: subject: Social and Behavioral Sciences

description: To date, there is a dearth of literature investigating the potential utility of psychosocial approaches in stroke rehabilitation. The current review explores the theoretical foundations regarding the influence of psychosocial resources on rehabilitation outcomes and life participation in stroke survivors with chronic communication disorders. The authors are interested in determining what factors characterize psychosocial resilience and interventions that indicate potential facilitation of psychosocial resilience among adult stroke survivors with communication disorders.
Particle-unstable light nuclei with a Sturmian approach that preserves the Pauli principle
Creators: name: Canton, L.
name: Amos, K.
name: Karataglidis, S.
name: Pisent, G.
name: Svenne, J. P.
name: van der Knijff, D.
Publisher: name: arXiv
Year: 2007
Subjects: subject: Nuclear Theory (nucl-th)
subject: FOS: Physical sciences

description: Sturmian theory for nucleon-nucleus scattering is discussed in the presence of all the phenomenological ingredients necessary for the description of weakly-bound (or particle-unstable) light nuclear systems. Currently, we use a macroscopic potential model of collective nature. The analysis shows that the couplings to low-energy collective-core excitations are fundamental but they are physically meaningful only if the constraints introduced by the Pauli principle are taken into account. The formalism leads one to discuss a new concept, Pauli hindrance, which appears to be important to understand the structure of weakly-bound and unbound systems.
description: 5 pages, 2 figures, 1 table, contribution to proceedings of "18th International IUPAP Conference on Few-Body Problems in Physics," Santos, Brazil, August 21-26, 2006
Η Δραματοποίηση στα βιβλία του μαθήματος των Θρησκευτικών στο Γυμνάσιο
Creators: name: Μυρίδου, Μαρία Ευσταθίου
Publisher: name: Aristotle University of Thessaloniki
Year: 2014
Subjects: Εκπαιδευτικό Δράμα
Μάθημα των Θρησκευτικών
Ανάλυση Περιεχομένου
Drama in Education
Religious Education
Content analysis

description: Σκοπός της δικής μας εργασίας ήταν να καταδείξουμε με έρευνα, ποσοτικά και ποιοτικά, τη συχνότητα των αναφορών στην έννοια του Εκπαιδευτικού Δράματος και τη χρησιμότητά του στα βιβλία του Μαθήματος των Θρησκευτικών, τόσο στο Βιβλίο Μαθητή, όσο και στο Βιβλίο του Εκπαιδευτικού στο Γυμνάσιο. Στο θεωρητικό κομμάτι της εργασίας επιχειρήσαμε να παρουσιάσουμε τη σύζευξη ανάμεσα στο Εκπαιδευτικό Δράμα και στο Μάθημα των Θρησκευτικών, ώστε να γίνει κατανοητή η χρησιμότητα και η καταλληλότητα του Εκπαιδευτικού Δράματος στη διδασκαλία του μαθήματος. Επίσης προσεγγίσαμε εννοιολογικά τα μέσα του Εκπαιδευτικού Δράματος και της Παιγνιώδους Διδασκαλίας, τα οποία συναντήσαμε στα σχολικά εγχειρίδια. Στο ερευνητικό κομμάτι της εργασίας μας (ανάλυση περιεχομένου), τα συμπεράσματά μας αναφέρονται τόσο στις ποσοτικές μετρήσεις, αλλά κυρίως στις ποιοτικές εκτιμήσεις για τη χρησιμότητα του Εκπαιδευτικού Δράματος και της Παιγνιώδους Διδασκαλίας στο Μάθημα των Θρησκευτικών του Γυμνασίου με στόχο τον εκσυγχρονισμό της διδακτικής πράξης.
description: The basic purpose of the thesis is to demonstrate via research, such as quantitatively as qualitatively, the frequency of the notion of Drama in Education and its use in course books of Religious Education of Gymnasium, such as Student Book as the Book of the Teacher. The theoretical part of thesis focused in presenting of Drama in Education and the subject of Religious Education, in order to be understood utility and appropriateness of Drama in Education at the educational process. Furthermore, we approached the notion of educational means such as Drama in Education and Playful Learning, that we have met in school books. At the research component of thesis (content analysis) conclusions are referred to quantitative measurements, but basically to qualitative estimate of utility Drama in Education and Playful Learning as teaching tools of Religious Education at Gymnasium, in order to modernize the educational practice.
Grade six students understanding of metaphor in informational text
Creators: name: Faulkner, Leigh A.
Publisher: name: University of British Columbia
Year: 2009

description: Metaphor research has become widespread. However, students’ understanding of metaphor in informational text has received little study. With increased use of informational trade books in the classroom, research in this area is needed. Fifty-five grade six students with Canadian English as their first language participated in the study. Their understanding of metaphors in excerpts from three recently published informational trade books was examined by the use of the reading think aloud technique and multiple choice activities. One think aloud was completed by each student in both individual and dyadic conditions. Multiple choice activities were completed individually after reading, but with the text available. The think-aloud protocols were examined using specific-trait analysis, holistic scoring, and miscue analysis. The multiple choice activities were scored against anticipated adult-like understanding and the results were subjected to standard statistical tests. Level of understanding of metaphors varied widely among students, with the overall average being about 65%. Contrary to prediction, understanding was significantly higher in the individual condition compared to the dyadic condition. Although part of this difference could be attributed to differences in passage difficulty, the anticipated scaffolding effect of reading with a partner was not found. The reading think aloud was a rich source of information about both the meaning students constructed and the meaning-construction process. The study suggested that the think aloud could be used in the classroom as an effective learning device, particularly in that it allowed less-capable readers to participate as equal partners in what might otherwise have been a frustrating reading task. Overall, there emerged a picture of students at various points along the path to full adult mastery of metaphor, with some students already demonstrating an adult level of understanding. Level of text understanding was consistent with level of metaphor understanding. The only metaphor-type effect identified was for metaphors with copula-verb syntactic-frame structure. Abstractness of the words in the metaphors did not affect meaning construction; however, conventionality of the metaphorical expressions did influence understanding.
Intermittent dynamics, strong correlations, and bit-error-rate in multichannel optical fiber communication systems
Creators: name: Peleg, Avner
Publisher: name: arXiv
Year: 2006
Subjects: subject: Optics (physics.optics)
subject: FOS: Physical sciences

description: We investigate the effects of delayed Raman response on pulse dynamics in massive multichannel optical fiber communication systems. Taking into account the stochastic nature of pulse sequences in different frequency channels and the Raman induced energy exchange in pulse collisions we show that the pulse parameters exhibit intermittent dynamic behavior, and that the pulse amplitudes exhibit relatively strong and long-range correlations. Moreover, we find that the Raman-induced cross frequency shift is the main intermittency-related mechanism leading to bit pattern deterioration and evaluate the bit-error-rate of the system.
description: 17 pages, 4 figures. Submitted to Phys. Lett. A
Experimental entanglement verification and quantification via uncertainty relations
Creators: name: Wang, Zhi-Wei
name: Huang, Yun-Feng
name: Ren, Xi-Feng
name: Zhang, Yong-Sheng
name: Guo, Guang-Can
Publisher: name: arXiv
Year: 2006
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: We report on experimental studies on entanglement quantification and verification based on uncertainty relations for systems consisting of two qubits. The new proposed measure is shown to be invariant under local unitary transformations, by which entanglement quantification is implemented for two-qubit pure states. The nonlocal uncertainty relations for two-qubit pure states are also used for entanglement verification which serves as a basic proposition and promise to be a good choice for verification of multipartite entanglement.
description: 5 pages, 3 figures and 2 tables
Coulomb blockade and transport in a chain of one-dimensional quantum dots
Creators: name: Fogler, M. M.
name: Malinin, S. V.
name: Nattermann, T.
Publisher: name: arXiv
Year: 2006
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Disordered Systems and Neural Networks (cond-mat.dis-nn)
subject: FOS: Physical sciences

description: A long one-dimensional wire with a finite density of strong random impurities is modelled as a chain of weakly coupled quantum dots. At low temperature T and applied voltage V its resistance is limited by "breaks": randomly occuring clusters of quantum dots with a special length distribution pattern that inhibits the transport. Due to the interplay of interaction and disorder effects the resistance can exhibit T and V dependences that can be approximated by power laws. The corresponding two exponents differ greatly from each other and depend not only on the intrinsic electronic parameters but also on the impurity distribution statistics.
description: 4 pages, 1 figure. Changes from v2: Dropped discussion of the high-field regime. Added discussion of mesoscopic fluctuations and multiple channels in the quasi-1D case. Improved presentation style
On relation between generalized diffusion equations and subordination schemes
Creators: name: Chechkin, A.
name: Sokolov, I. M.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Statistical Mechanics (cond-mat.stat-mech)
subject: Soft Condensed Matter (cond-mat.soft)
subject: Mathematical Physics (math-ph)
subject: Probability (math.PR)
subject: FOS: Physical sciences
subject: FOS: Mathematics

description: Generalized (non-Markovian) diffusion equations with different memory kernels and subordination schemes based on random time change in the Brownian diffusion process are popular mathematical tools for description of a variety of non-Fickian diffusion processes in physics, biology and earth sciences. Some of such processes (notably, the fluid limits of continuous time random walks) allow for either kind of description, but other ones do not. In the present work we discuss the conditions under which a generalized diffusion equation does correspond to a subordination scheme, and the conditions under which a subordination scheme does possess the corresponding generalized diffusion equation. Moreover, we discuss examples of random processes for which only one, or both kinds of description are applicable.
Quantum discontinuity fixed point and renormalization group flow of the SYK model
Creators: name: Smit, Roman
name: Valentinis, Davide
name: Schmalian, Jörg
name: Kopietz, Peter
Publisher: name: arXiv
Year: 2020
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: We determine the global renormalization group (RG) flow of the Sachdev-Ye-Kitaev (SYK) model. This flow allows for an understanding of the surprising role of critical slowing down at a quantum first-order transition in strongly-correlated electronic systems. From a simple truncation of the infinite hierarchy of the exact functional RG flow equations we identify several fixed points: Apart from a stable fixed point, associated with the celebrated non-Fermi liquid state of the model, we find another stable fixed point related to an integer-valence state. These stable fixed points are separated by a discontinuity fixed point with one relevant direction, describing a quantum first-order transition. Most notably, the fermionic spectrum continues to be quantum critical even at the discontinuity fixed point. This rules out a description of this quantum first-order transition in terms of a local effective Ising variable that is established for classical transitions. It reveals that quantum phase coexistence can be a genuine critical state of matter.
description: 6 pages, 4 figures
A Kiefer--Wolfowitz theorem for convex densities
Creators: name: Balabdaoui, Fadoua
name: Wellner, Jon A.
Publisher: name: arXiv
Year: 2007
Subjects: subject: Statistics Theory (math.ST)
subject: FOS: Mathematics
subject: 62G10, 62G20 (Primary); 62G30 (Secondary)

description: Kiefer and Wolfowitz [Z. Wahrsch. Verw. Gebiete 34 (1976) 73--85] showed that if $F$ is a strictly curved concave distribution function (corresponding to a strictly monotone density $f$), then the Maximum Likelihood Estimator $\hat{F}_n$, which is, in fact, the least concave majorant of the empirical distribution function $\mathbb {F}_n$, differs from the empirical distribution function in the uniform norm by no more than a constant times $(n^{-1}\log n)^{2/3}$ almost surely. We review their result and give an updated version of their proof. We prove a comparable theorem for the class of distribution functions $F$ with convex decreasing densities $f$, but with the maximum likelihood estimator $\hat{F}_n$ of $F$ replaced by the least squares estimator $\widetilde{F}_n$: if $X_1,..., X_n$ are sampled from a distribution function $F$ with strictly convex density $f$, then the least squares estimator $\widetilde{F}_n$ of $F$ and the empirical distribution function $\mathbb {F}_n$ differ in the uniform norm by no more than a constant times $(n^{-1}\log n)^{3/5}$ almost surely. The proofs rely on bounds on the interpolation error for complete spline interpolation due to Hall [J. Approximation Theory 1 (1968) 209--218], Hall and Meyer [J. Approximation Theory 16 (1976) 105--122], building on earlier work by Birkhoff and de Boor [J. Math. Mech. 13 (1964) 827--835]. These results, which are crucial for the developments here, are all nicely summarized and exposited in de Boor [A Practical Guide to Splines (2001) Springer, New York].
description: Published at http://dx.doi.org/10.1214/074921707000000256 in the IMS Lecture Notes Monograph Series (http://www.imstat.org/publications/lecnotes.htm) by the Institute of Mathematical Statistics (http://www.imstat.org)
Methodology for design of templates of text communication messages for software marketing
Creators: name: Malakhovskaya, E. K.
name: Ekhlakov, Y. P.
name: Senchenko, P. V.
name: Sidorov, A. A.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Human-Computer Interaction (cs.HC)
subject: FOS: Computer and information sciences
subject: K.0

description: A methodology is proposed for design of templates of text communication messages that are based on best practices of experts in software marketing, ideas of marketing, communication theory, copywriting, media linguistics, semiotics. Description of the subject area is based on conceptual modeling and production systems. For the purposes of testing, the methodology was used as the basis of a software product. Decision support recommender system for design of communication messages for software marketing.
description: 4 p
Fluctuating Cu-O-Cu Bond model of high temperature superconductivity in cuprates
Creators: name: Newns, D. M.
name: Tsuei, C. C.
Publisher: name: arXiv
Year: 2006
Subjects: subject: Superconductivity (cond-mat.supr-con)
subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: Twenty years of extensive research has yet to produce a general consensus on the origin of high temperature superconductivity (HTS). However, several generic characteristics of the cuprate superconductors have emerged as the essential ingredients of and/or constraints on any viable microscopic model of HTS. Besides a Tc of order 100K, the most prominent on the list include a d-wave superconducting gap with Fermi liquid nodal excitations, a d-wave pseudogap with the characteristic temperature scale T*, an anomalous doping-dependent oxygen isotope shift, nanometer-scale gap inhomogeneity, etc.. The key role of planar oxygen vibrations implied by the isotope shift and other evidence, in the context of CuO2 plane symmetry and charge constraints from the strong intra-3d Coulomb repulsion U, enforces an anharmonic mechanism in which the oxygen vibrational amplitude modulates the strength of the in-plane Cu-Cu bond. We show, within a Fermi liquid framework, that this mechanism can lead to strong d-wave pairing and to a natural explanation of the salient features of HTS.
Time modulation of atom sources
Creators: name: del Campo, A.
name: Muga, J. G.
name: Moshinsky, M.
Publisher: name: arXiv
Year: 2006
Subjects: subject: Other Condensed Matter (cond-mat.other)
subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: Sudden turn-on of a matter-wave source leads to characteristic oscillations of the probability density which are the hallmark feature of diffraction in time. The apodization of matter waves relies on the use of smooth aperture functions which suppress such oscillations. The analytical dynamics arising with different aperture functions are discussed systematically for switching-on processes, and for single and many-pulse formation procedures. The possibility and time scale of a revival of the diffraction-in-time pattern is also analysed. Similar modulations in time of the pulsed output coupling in atom-lasers are responsible for the dynamical evolution and characteristics of the beam profile. For multiple pulses, different phase schemes and regimes are described and compared. Strongly overlapping pulses lead to a saturated, constant beam profile in time and space, up to the revival phenomenon.
description: 13 pages, 8+1 figures, references added, minor corrections
Updated Constraints on the Minimal Supergravity Model
Creators: name: Djouadi, Abdelhak
name: Drees, Manuel
name: Kneur, Jean-Loic
Publisher: name: arXiv
Year: 2006
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: We provide an up-to-date analysis of the parameter space of the minimal supergravity model (mSUGRA). Novel features include the new central value of the top quark mass, an improved calculation of the masses of the supersymmetric particles and the neutral Higgs bosons, constraints from b to s \ell^+ \ell^- decays, and a careful treatment of the most important experimental and theoretical uncertainties. In addition to the by now traditional plots of the allowed region in the (m_0, m_{1/2}) plane, we show allowed regions in the planes spanned by pairs of {\em physical} sparticle or Higgs boson masses. Moreover, we search for the minimal allowed masses of new particles for various sets of constraints. We find that in many cases the direct experimental limits from collider and Dark Matter searches can be saturated even in this minimal model, and even after including the by now quite restrictive constraint on the Dark Matter relic density.
description: About 35 pages, numerous postscript figures. Corrected a few typos and added two historical references; version to appear in JHEP
The relationship between elementary classroom collections and the school library resource centre program
Creators: name: Doiron, Ray
Publisher: name: University of British Columbia
Year: 2009

description: The school library resource centre and the collection of trade books that classroom teachers gather in their classrooms were the focus of an exploratory, descriptive study designed around the first stages of an action research model. Little research had been done on how effective classroom teachers have been at acquiring trade books for their classroom collections, and on how teacher-librarians, working in partially or fully integrated school library resource centre programs, helped make trade books accessible to elementary teachers and students. One instrument, The Survey of Elementary Classroom Collections. was designed to examine four descriptive areas: the contents and size of classroom collections, the source of trade books for these collection, the organization and management of classroom collections, and the use classroom teachers make of these trade books. The 205 elementary English language classroom teachers in one school district were sent a Survey and 80% responded. The series of interviews that followed were conducted with a stratified random sample of 30 classroom teachers, nine principals and seven teacher-librarians. The stratification was organized by Phases 1, 2 or 3 of school library program development, which were determined by the score on a second instrument. The Profile of School Library Resource Centre Programs. and from information on staffing, resources and teacher-librarian experience. Results were analyzed under the four areas explored in the Survey, by grade level and by Phase. A detailed description of the classroom collections led to the development of the Independent, Interactive and Integrated models for classroom collections. Each reflected a different concept of the classroom collection, its role in the literacy program and its relationship with the school library resource centre program. Indications were that a collaborative approach to trade book provisioning emerged in schools where the school library resource centre program was more fully integrated into the school curriculum. Details on a school-based/district-wide strategy to build a collaborative approach were given, as well as suggestions for a plan of action for individual schools and for further research to explore questions raised by this study.
Achieving the ultimate quantum timing resolution
Creators: name: Ansari, Vahid
name: Brecht, Benjamin
name: Gil-López, Jano
name: Donohue, John M.
name: Řeháček, Jaroslav
name: Hradil, Zdeněk
name: Sánchez-Soto, Luis L.
name: Silberhorn, Christine
Publisher: name: arXiv
Year: 2020
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: Accurate time-delay measurement is at the core of many modern technologies. Here, we present a temporal-mode demultiplexing scheme that achieves the ultimate quantum precision for the simultaneous estimation of the temporal centroid, the time offset, and the relative intensities of an incoherent mixture of ultrashort pulses at the single-photon level. We experimentally resolve temporal separations ten times smaller than the pulse duration, as well as imbalanced intensities differing by a factor of $10^{2}$. This represents an improvement of more than an order of magnitude over the best standard methods based on intensity detection.
Ανάπτυξη εργαστηριακού υλικού προσομοίωσης για διδασκαλία ασύρματων δικτύων
Creators: name: Δαλιάνης, Δημήτριος Παύλου
Publisher: name: Aristotle University of Thessaloniki
Year: 2013
Subjects: Προσομοίωση
Ασύρματα δίκτυα
ns-2
Simulation
Wireless Networks

description: Σκοπός της παρούσας εργασίας είναι η παρουσίαση εργαστηριακού υλικού που μπορεί να χρησιμοποιηθεί στην διδασκαλία των ασύρματων δικτύων. Κάθε ένα κεφάλαιο της εργασίας αποτελεί και μία άσκηση. Στο 1ο κεφάλαιο γίνεται μια εισαγωγή στον ns-2 και στα εργαλεία που παρέχει αυτός και παρουσιάζονται ενδεικτικά προγράμματα που βοηθούν στην κατανόηση τους. Από το κεφάλαιο 2 έως το 6 εξετάζονται οι μηχανισμοί του πρωτοκόλλου MAC IEEE 802.11 για τα ασύρματα δίκτυα. Συγκεκριμένα εξετάζονται οι μηχανισμοί του παραθύρου ανταγωνισμού, η φυσική και η εικονική ακρόαση στο μέσο, τα φαινόμενα λιμοκτονίας και αδικίας που παρατηρούνται μεταξύ των σταθμών ενός δικτύου, η επιβάρυνση που προσθέτουν τα πακέτα του MAC επιπέδου και η σχέση του ρυθμού μετάδοσης και του κατωφλιού ακρόασης. Στο 7ο κεφάλαιο γίνεται παρουσίαση των διαφορετικών μοντέλων διάδοσης και εξετάζεται πως επηρεάζει την απόδοση του δικτύου ο καθένας από αυτούς. Στο 8ο κεφάλαιο εξετάζουμε πως μπορεί να επηρεαστεί η απόδοση ενός δικτύου όπου συμβαίνουν εκπομπές πακέτων σε όλους τους σταθμούς ανάλογα με την αυξομείωση της πιθανότητας αναμετάδοσης. Στο 9ο και 10ο κεφάλαια εξετάζονται τα πρωτόκολλα δρομολόγησης στα ασύρματα δίκτυα. Στο 9ο κεφάλαιο μελετάται ένα πρωτόκολλο που χρησιμοποιεί πίνακες δρομολόγησης, το DSDV. Στο 10ο κεφάλαιο εξετάζονται δύο πρωτόκολλα δρομολόγησης κατ’ απαίτηση, το DSR και το AODV.
description: The aim of the present thesis was the presentation of material that can be used in computer labs for the teaching of wireless networks. Each chapter of the thesis constitutes an exercise. In the 1st chapter we make an introduction to ns-2 and its tools and indicative programs are presented in order to comprehend them. Through chapters 2 to 6 we examine the mechanisms of the MAC IEEE 802.11 protocol for wireless networks. In particular, we examine the mechanisms of the contention window, the physical and virtual carrier sensing, the starvation and unfairness that is observed between the stations of a network, the overhead of the MAC level packets and the relation between bitrate and carrier sense threshold. In the 7th chapter we present the different propagation models and we examine how each one affects the network efficiency. In the 8th chapter we examine how the efficiency of the network is affected when a packet must reach every station and each station chooses to transmit the packet based on a probability. In chapters 9 and 10 we examine routing protocols in wireless networks. In the 9th chapter we study a protocol that uses routing tables, DSDV. In the 10th chapter we examine two on demand routing protocols, DSR and AODV.
Bulk black hole, escaping photons, and bounds on violations of Lorentz invariance
Creators: name: Khlebnikov, S.
Publisher: name: arXiv
Year: 2007
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: There are reasons (which we enumerate) to think that an infinite extra dimension will harbor a black hole. In this case, brane-localized modes of gravity and gauge fields become quasilocalized, and light from a distant object can become extinct as it is lost to the black hole. In a concrete scenario, where the photon is localized by gravity, we find that the extinction rate for propagating photons is at least comparable to the correction to the real part of the frequency. That results, for example, in a stringent bound on renormalization of the speed of light.
description: 13 pages; v3: minor changes, to be published in Phys. Rev. D
Μελέτη της επίδρασης της χρήσης ιστοτόπων κοινωνικής δικτύωσης στους εφήβους, με δειγματοληψία και στατιστική ανάλυση
Creators: name: Θεοδωρίδου, Αλεξάνδρα Αδάμ
Publisher: name: Aristotle University of Thessaloniki
Year: 2014
Subjects: κοινωνικά δίκτυα
δειγματοληψία
εφηβεία
social networks
sampling
adolescence

description: Η κοινωνική δικτύωση αποτελεί μια ιδιαίτερα δημοφιλή επιλογή των μαθητών για την επικοινωνία τους σήμερα μέσω του Διαδικτύου. Όμως η χρήση της κρύβει κινδύνους γύρω από το θέμα της ιδιωτικότητας (privacy) και του προσωπικού απορρήτου του χρήστη. Επιπλέον υπάρχουν τα φαινόμενα του εθισμού (addiction), της παρενόχλησης και του εκφοβισμού (cyber bullying). Καταρτίσαμε ένα ερωτηματολόγιο διερευνώντας την ασφαλή χρήση της κοινωνικής δικτύωσης από τους μαθητές Δευτεροβάθμιας Εκπαίδευσης, συγκεκριμένα μαθητών Λυκείου. Παρουσιάζουμε τα αποτελέσματα του δείγματος 66 μαθητών και παραθέτουμε συμπεράσματα και κατευθύνσεις προς την ορθή χρήση της κοινωνικής δικτύωσης.
description: Social networking is an extremely popular choice for communication via Internet by adolescents today. But its use hides dangers to the subject of privacy and personal secrecy of the user. Additionaly there are cases of addiction and cyber bullying. We formed a questionnaire searching the safe use of SNS by high school students. We present the outcomes of a 66 student sample and we come to conclusions and directions to a correct use of social networks.
Ζωντανεύοντας e-στορίες: η λογοτεχνική αγωγή στο διαδίκτυο
Creators: name: Τσιουπλή, Ευγενία Λάζαρου
Publisher: name: Aristotle University of Thessaloniki
Year: 2014
Subjects: Διαδικτυακά περιοδικά
Διαδικτυακή λογοτεχνία
Πρόσληψη της λογοτεχνίας
Digital online magazines
Digital literature
Literature perception
Λογοτεχνία-Διαδίκτυο

description: Σκοπός της παρούσας εργασίας είναι να μελετηθούν οι αλλαγές που έχει επιφέρει η χρήση του διαδικτύου και των νέων τεχνολογιών στη λογοτεχνία και στην πρόσληψή της γενικότερα και στο κειμενικό είδος των περιοδικών ειδικότερα. Η ερευνητική μέθοδος που επιλέχθηκε είναι η μελέτη περίπτωσης ενός διαδικτυακού περιοδικού το οποίο ασχολείται με τη λογοτεχνία για παιδιά και νέους. Στο θεωρητικό μέρος εξετάζεται η λογοτεχνία ως παράγων διαμόρφωσης ταυτοτήτων στα παιδιά και στους νέους και διασαφηνίζονται έννοιες όπως ο ψηφιακός γραμματισμός, το ψηφιακό χάσμα, η ψηφιακή σοφία κ.ά Ακολούθως, μελετώνται οι έννοιες της ψηφιακής λογοτεχνίας, της ψηφιακής ανάγνωσης και των διαδικτυακών περιοδικών. Στο ερευνητικό μέρος περιγράφεται η μεθοδολογία της έρευνας και η διεξαγωγή της. Γίνεται αναλυτική παρουσίαση των διαδικτυακών τόπων του περιοδικού και οι τρόποι πρόσληψης του από τους εκπαιδευτικούς, με ημι-δομημένη συνέντευξη και των μαθητών με ερωτηματολόγιο.
description: The aim of present thesis was the approach of changes that have occurred by the use of internet and new technologies as well, relatively with literature and its perception in general and on genre of magazines in particular. The researching method which was chosen was case study of an online magazine which deals with literature for children and young people. The theoretical part examines literature as a shaping factor of children and young people’s identities and analyses concepts such as digital literacy, digital divide, digital wisdom etc. Moreover, we have studied the field of digital literature, digital reading and online magazines. In the research part is described the methodology and main procedure of the research. A detailed presentation of internet sites of the magazine is included as well as the ways of its perception by teachers, using the method of semi - structured interview and by students using a questionnaire.
Polydisperse Streaming Instability I. Tightly coupled particles and the terminal velocity approximation
Creators: name: Paardekooper, Sijme-Jan
name: McNally, Colin P.
name: Lovascio, Francesco
Publisher: name: arXiv
Year: 2020
Subjects: subject: Earth and Planetary Astrophysics (astro-ph.EP)
subject: Fluid Dynamics (physics.flu-dyn)
subject: FOS: Physical sciences

description: We introduce a polydisperse version of the streaming instability, where the dust component is treated as a continuum of sizes. We show that its behaviour is remarkably different from the monodisperse streaming instability. We focus on tightly coupled particles in the terminal velocity approximation and show that unstable modes that grow exponentially on a dynamical time scale exist. However, for dust to gas ratios much smaller than unity they are confined to radial wave numbers that are a factor $\sim 1/\overline{\rm St}$ larger than where the monodisperse streaming instability growth rates peak. Here $\overline{\rm St} \ll 1$ is a suitable average Stokes number for the dust size distribution. For dust to gas ratios larger than unity, polydisperse modes that grow on a dynamical time scale are found as well, similar as for the monodisperse streaming instability and at similarly large wave numbers. At smaller wave numbers, where the classical monodisperse streaming instability shows secular growth, no growing polydisperse modes are found under the terminal velocity approximation. Outside the region of validity for the terminal velocity approximation, we have found unstable epicyclic modes that grow on $\sim 10^4$ dynamical time scales.
description: 17 pages, 10 figures, 1 table. Submitted
Superclusters of galaxies in the 2dF redshift survey. III. The properties of galaxies in superclusters
Creators: name: Einasto, M.
name: Einasto, J.
name: Tago, E.
name: Saar, E.
name: Liivam"agi, L. J.
name: J~oeveer, M.
name: H"utsi, G.
name: Hein"am"aki, P.
name: M"uller, V.
name: Tucker, D.
Publisher: name: arXiv
Year: 2006
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: We use catalogues of superclusters of galaxies from the 2dF Galaxy Redshift Survey to study the properties of galaxies in superclusters. We compare the properties of galaxies in high and low density regions of rich superclusters, in poor superclusters and in the field, as well as in groups, and of isolated galaxies in superclusters of various richness. We show that in rich superclusters the values of the luminosity density smoothed on a scale of 8 \Mpc are higher than in poor superclusters: the median density in rich superclusters is $δ\approx 7.5$, in poor superclusters $δ\approx 6.0$. Rich superclusters contain high density cores with densities $δ> 10$ while in poor superclusters such high density cores are absent. The properties of galaxies in rich and poor superclusters and in the field are different: the fraction of early type, passive galaxies in rich superclusters is slightly larger than in poor superclusters, and is the smallest among the field galaxies. Most importantly, in high density cores of rich superclusters ($δ> 10$) there is an excess of early type, passive galaxies in groups and clusters, as well as among those which do not belong to groups or clusters. The main galaxies of superclusters have a rather limited range of absolute magnitudes. The main galaxies of rich superclusters have larger luminosities than those of poor superclusters and of groups in the field. Our results show that both the local (group/cluster) environments and global (supercluster) environments influence galaxy morphologies and their star formation activity.
description: 13 pages, 10 figures, submitted to Astronomy and Astrophysics
Maximum entropy kinetic matching conditions for heavy-ion collisions
Creators: name: Everett, Derek
name: Chattopadhyay, Chandrodoy
name: Heinz, Ulrich
Publisher: name: arXiv
Year: 2021
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: Nuclear Theory (nucl-th)
subject: FOS: Physical sciences

description: Coupling hadronic kinetic theory models to fluid dynamics in phenomenological studies of heavy ion collisions requires a prescription for ``particlization''. Existing particlization models are based on implicit or explicit assumptions about the microscopic degrees of freedom that go beyond the information provided by the preceding fluid dynamical history. We propose an alternative prescription which uses only macroscopic information provided by the hydrodynamic output. This method follows directly from the connections between information theory and statistical mechanics.
description: 13 pages, 5 figures
Impacts of Accumulated Particulate Organic Matter on Oxygen Consumption and Organic Micro-Pollutant Elimination in Bank Filtration and Soil Aquifer Treatment
Creators: name: Filter, Josefine
name: Jekel, Martin
name: Ruhl, Aki Sebastian
Publisher: name: Technische Universität Berlin
Year: 2017
Subjects: subject: 500 Naturwissenschaften und Mathematik
subject: bank filtration
subject: soil aquifer treatment
subject: sediments
subject: organic micro-pollutants
subject: particulate organic matter
subject: oxygen consumption

description: Bank filtration (BF) and soil aquifer treatment (SAT) are efficient natural technologies in potable water reuse systems. The removal of many organic micro-pollutants (OMPs) depends on redox-conditions in the subsoil, especially on the availability of molecular oxygen. Due to microbial transformation of particulate and dissolved organic constituents, oxygen can be consumed within short flow distances and induce anoxic and anaerobic conditions. The effect of accumulated particulate organic carbon (POC) on the fate of OMPs in BF and SAT systems is not fully understood. Long-term column experiments with natural sediment cores from the bank of Lake Tegel and from a SAT basin were conducted to investigate the impact of accumulated POC on dissolved organic carbon (DOC) release, on oxygen consumption, on mobilization of iron and manganese, and on the elimination of the organic indicator OMPs. The cores were fed with aerated tap water spiked with OMPs to exclude external POC inputs. Complete oxygen consumption within the first infiltration decimeter in lake sediments caused mobilization of iron, manganese, and DOC. Redox-sensitive OMPs like diclofenac, sulfamethoxazole, formylaminoantipyrine, and gabapentin were eliminated by more than 50% in all sediment cores, but slightly higher residual concentrations were measured in effluents from lake sediments, indicating a negative impact of a high oxygen consumption on OMP removal.
The identity type weak factorisation system
Creators: name: Gambino, Nicola
name: Garner, Richard
Publisher: name: arXiv
Year: 2008
Subjects: subject: Logic (math.LO)
subject: Category Theory (math.CT)
subject: FOS: Mathematics
subject: 03B15; 18C50; 18B40

description: We show that the classifying category C(T) of a dependent type theory T with axioms for identity types admits a non-trivial weak factorisation system. We provide an explicit characterisation of the elements of both the left class and the right class of the weak factorisation system. This characterisation is applied to relate identity types and the homotopy theory of groupoids.
description: 25 pages; accepted for publication in Theoretical Computer Science
Predicting the future state of disturbed LTI systems: A solution based on high-order observers
Creators: name: Castillo, Alberto
name: Garcia, Pedro
Publisher: name: arXiv
Year: 2020
Subjects: subject: Systems and Control (eess.SY)
subject: FOS: Electrical engineering, electronic engineering, information engineering

description: Predicting the state of a system in a relatively near future time instant is often needed for control purposes. However, when the system is affected by external disturbances, its future state is dependent on the forthcoming disturbance; which is, in most of the cases, unknown and impossible to measure. In this scenario, making predictions of the future system-state is not straightforward and, indeed, there are scarce contributions provided to this issue. This paper treats the following problem: given a LTI system affected by continuously differentiable unknown disturbances, how its future state can be predicted in a sufficiently small time-horizon by high-order observers. Observer design methodologies in order to reduce the prediction errors are given. Comparisons with other solutions are also established.
description: 5 pages, 1 figure
Παραθαλάσσιοι οικισμοί Ιονίων Νήσων: Χαρακτηριστικά- Δυναμική- Προοπτικές: Μια χαρτογραφική προσέγγιση
Creators: name: Ρώμα- Αθανασιάδου, Έλλη
Publisher: name: Aristotle University of Thessaloniki
Year: 2015
Subjects: παραθαλάσσιοι οικισμοί
χαρτογραφική βάση
Ιόνια Νησιά
coastal settlements
cartographic database
Ionian Islands

description: Η παρούσα διπλωματική επιχειρεί την κατανόηση του παράκτιου χώρου, μέσα από την κατανόηση των επιμέρους χαρακτηριστικών του. Αποτελεί μια μελέτη περίπτωσης, επιχειρώντας την καταγραφή των χαρακτηριστικών των παραθαλάσσιων οικισμών των Ιόνιων Νησιών, μέσω της θεματικής χαρτογραφικής τους αποτύπωσης, και την παράλληλη διερεύνηση: α) του ρόλου τους και β) των δυνατοτήτων τους. Αρχικά γίνεται μια παρουσίαση του παράκτιου χώρου μέσα από την ελληνική νομοθεσία, στη συνέχεια συλλέγονται δεδομένα και δημιουργούνται οι βασικοί πίνακες δεδομένων που θα οδηγήσουν στη δημιουργία των θεματικών χαρτών. Παρουσιάζονται οι κατευθύνσεις του υπερκείμενου σχεδιασμού, που αφορούν τα Ιόνια Νησιά και τον παράκτιο χώρο τους. Ακολουθεί η επιλογή των εξεταζόμενων οικισμών και δίνεται ο ορισμός τους, βάσει της διπλωματικής. Στη συνέχεια αναλύονται τα χαρακτηριστικά τους μέσω χαρτών, πινάκων και διαγραμμάτων. Τέλος, επιλέγονται βάσει των εξεταζόμενων χαρακτηριστικών τους και της ανάλυσης που έχει προηγηθεί, οι 21 δυναμικότεροι παραθαλάσσιοι οικισμοί της Περιφέρειας και παρατίθενται κάποια τελικά συμπεράσματα.
description: Understanding of the coastal zone can only be achieved by analyzing and understanding the elements that make the whole. The present thesis focuses in a case study area about the Ionian Islands in order to examine the features of their coastal settlements, through categorizing and creating thematic maps about them. The purpose is to identify a)their role and b)their prospects. The thesis introduces a presentation of the coastal zones through the Greek law and legislation at the beginning and continues with the assembly of the data and the creation of the main attribute tables that will lead to the thematic cartography. At this point the examination of the directions of the strategic and regional planning that apply to the Ionian Islands and their coastal zone is important. Further on, for the purposes of the thesis, the definition of the coastal settlements is being given and the selection of those under examination is being done. Their characteristics are being analyzed through maps, tables and graphs. This analysis is followed by the selection and presentation of the most dynamic coastal settlements and by some final conclusions.
Topological Physics of Little Higgs Bosons
Creators: name: Hill, Christopher T.
name: Hill, Richard J.
Publisher: name: arXiv
Year: 2007
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: Topological interactions will generally occur in composite Higgs or Little Higgs theories, extra-dimensional gauge theories in which A_5 plays the role of a Higgs boson, and amongst the pNGB's of technicolor. This phenomena arises from the chiral and anomaly structure of the underlying UV completion theory, and/or through chiral delocalization in higher dimensions. These effects are described by a full Wess-Zumino-Witten term involving gauge fields and pNGB's. We give a general discussion of these interactions, some of which may have novel signatures at future colliders, such as the LHC and ILC.
description: 22 pages
Μελέτη επιπτώσεων στην κυκλοφορία λόγω έκτακτων συμβάντων στην Περιφερειακή οδό Θεσσαλονίκης με τη χρήση μοντέλου προσομοίωσης της κυκλοφορίας
Creators: name: Καρυώτη Ελένη Γεωργίου
Publisher: name: Aristotle University of Thessaloniki
Year: 2015
Subjects: έκτακτα συμβάντα
Περιφερειακή οδός Θεσσαλονίκης
μοντέλο προσομοίωσης της κυκλοφορίας
extraordinary events
Ring Road of Thessaloniki
traffic simulation model

description: Αντικείμενο της Διπλωματικής εργασίας αποτελεί η εξέταση των επιπτώσεων κυκλοφοριακών συμβάντων σε τμήμα της Περιφερειακής οδού Θεσσαλονίκης με την χρήση του μικροσκοπικού προγράμματος προσομοίωσης της κυκλοφορίας, Aimsun. Πραγματοποιείται περιγραφή της έννοιας της προσομοίωσης της κυκλοφορίας, των πλεονεκτημάτων και των μειονεκτημάτων της. Γίνεται αναφορά στις κατηγορίες των υποδειγμάτων προσομοίωσης δίνοντας έμφαση στην μικροσκοπική προσομοίωση καθώς και στα μαθηματικά υποδείγματα που περιγράφουν στην κίνηση των οχημάτων. Περιγράφεται στη συνέχεια η διαδικασία που ακολουθήθηκε στο λογισμικό Aimsun, από το στάδιο της δημιουργίας του δικτύου έως το στάδιο της προσομοίωσης των επιλεγμένων σεναρίων. Μέσω τις προσομοίωσης των διάφορων σεναρίων που καταρτίστηκαν και αποτελούν πιθανά οδικά συμβάντα, μελετώνται οι αλλαγές που υφίσταται η κυκλοφορία. Για την αξιολόγηση αυτών των μεταβολών, ορίστηκαν δείκτες λειτουργικής απόδοσης. Τα εξαγόμενα αποτελέσματα μελετήθηκαν σε τοπικό επίπεδο, το οποίο αφορά την περιοχή άμεσης επιρροής των συμβάντων και σε επίπεδο δικτύου, το οποίο αφορά τις έμμεσες επιπτώσεις των σεναρίων σε μια ευρύτερη περιοχή μελέτης. Από την αξιολόγηση των παραπάνω αποτελεσμάτων προκύπτουν χρήσιμα συμπεράσματα για το κάθε σενάριο.
description: Objective of this thesis is to examine the impact of traffic incidents on a part of Ring Road of Thessaloniki by using a microscopic traffic simulation program, Aimsun. The definition of traffic simulations, as well as description of the advantages and disadvantages, are given in detail. Moreover, the categories of simulation models are mentioned, emphasizing on microscopic simulation and on mathematical models which describe the way vehicles move. Then, the procedure followed in Aimsun software – from the process of creating the network to the stage of simulation of the selected scenarios - is described. Through the simulation of developed scenarios, which are potential road events, the ongoing performance changes in the traffic are studied. In order for these changes to be evaluated, operational performance indicators are used. The results were studied both at local and network level, which concerns the area of direct influence of the events and the indirect effects of the scenarios on the study area, respectively. The evaluation of the above results leads to useful conclusions for each scenario.
Updating judgments about randomness and conspiracy beliefs: Snowy images and expectations
Creators: name: Sutton, Robbie
name: Douglas, Karen
name: Leach, Stefan
Publisher: name: OSF Registries
Year: 2020
Subjects: subject: Social Psychology
subject: Social and Behavioral Sciences
subject: Psychology
subject: FOS: Psychology

description: Documents methods, predictions, and power analyses for an experimental study on judgments about randomness and conspiracy beliefs.
Tensor Charges, Quark Anomalous Magnetic Moments And Baryons
Creators: name: Mekhfi, M.
Publisher: name: arXiv
Year: 2006
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: We propose an ultimate upgrade of the Karl- Sehgal (KS) formula which relates baryon magnetic moments to the spin structure of constituent quarks, by adding anomalous magnetic moments of quarks. We first argue that relativistic nature of quarks inside baryons requires introduction of two kinds of magnetisms, one axial and the other tensoriel. The first one is associated with integrated quark helicity distributions(standard) and the second with integrated transversity distributions . The weight of each contribution is controlled by the combination of two parameters, the ratio of the quark mass to the average kinetic energy and the quark anomalous magnetic moment. The quark anomalous magnetic moment is shown to be correlated to transversity and both parameters are necessary ingredients in describing relativistic quarks. The proposed formula, when confronted with baryon magnetic moments data with reasonable inputs, confirms that anomalous magnetic moments of quarks are unavoidable intrinsic properties .
description: Talk given at the 17 th International Spin Physics Symposium Kyoto, Japan Oct 2-7 '06