cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Pitfalls on the determination of the universality class of radial clusters
Creators: name: Ferreira, S. C.
name: Alves, S. G.
Publisher: name: arXiv
Year: 2006
Subjects: subject: Statistical Mechanics (cond-mat.stat-mech)
subject: FOS: Physical sciences

description: The self-affinity of growing systems with radial symmetry, from tumors to grain-grain displacement, has devoted increasing interest in the last decade. In this work, we analyzed features about the interface scaling of these clusters through large scale simulations (up to $3\times 10^7$ particles) of two-dimensional growth processes with special emphasis on the off-lattice Eden model. The central objective is to discuss an important pitfall associated to the evaluation of the growth exponent $β$ of these systems. We show that the $β$ value depends on the choice of the origin used to determine the interface width. We considered two strategies frequently used. When the width is evaluated in relation to the center of mass (CM) of the border, the exponent obtained for the Eden model was $β_{CM}=0.404\pm0.013$, in very good agreement with previous reported values. However, if the border CM is replaced by the initial seed position (a static origin), the exponent $β_0=0.333\pm 0.010$, in complete agreement with the KPZ value $β_{KPZ}=1/3$, was found. The difference between $β_{CM}$ and $β_{0}$ was explained through the border CM fluctuations that grow faster than the overall interface fluctuations. Indeed, we show that the exponents $β_0$ and $β_{CM}$ characterize large and small wavelength fluctuations of the interface, respectively. These finds were also observed in three distinct lattice models, in which the lattice-imposed anisotropy is absent.
description: 11 pages, 6 figures, to appear in J. Stat. Mech
Source population synthesis and the Galactic diffuse gamma-ray emission
Creators: name: Strong, A. W.
Publisher: name: arXiv
Year: 2006
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: Population synthesis is used to study the contribution from undetected sources to the Galactic ridge emission measured by EGRET. Synthesized source counts are compared with the 3rd EGRET catalogue at low and high latitudes. For pulsar-like populations, 5-10% of the emission >100 MeV comes from sources below the EGRET threshold. A steeper luminosity function can increase this to 20% without violating EGRET source statistics. Less luminous populations can produce much higher values without being detected. Since the unresolved source spectrum is different from the interstellar spectrum, it could provide an explanation of the observed MeV and GeV excesses above the predictions, and we give an explicit example of how this could work.
description: Astrophysics and Space Science, in press. (Proceedings of Conference 'The multi-messenger approach to high-energy gamma-ray sources', Barcelona, 2006). Minor changes for accepted version, updated references
Recoiling from a kick in the head-on collision of spinning black holes
Creators: name: Choi, Dae-Il
name: Kelly, Bernard J.
name: Boggs, William D.
name: Baker, John G.
name: Centrella, Joan
name: van Meter, James
Publisher: name: arXiv
Year: 2007
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: Recoil ``kicks'' induced by gravitational radiation are expected in the inspiral and merger of black holes. Recently the numerical relativity community has begun to measure the significant kicks found when both unequal masses and spins are considered. Because understanding the cause and magnitude of each component of this kick may be complicated in inspiral simulations, we consider these effects in the context of a simple test problem. We study recoils from collisions of binaries with initially head-on trajectories, starting with the simplest case of equal masses with no spin and then adding spin and varying the mass ratio, both separately and jointly. We find spin-induced recoils to be significant relative to unequal-mass recoils even in head-on configurations. Additionally, it appears that the scaling of transverse kicks with spins is consistent with post-Newtonian theory, even though the kick is generated in the nonlinear merger interaction, where post-Newtonian theory should not apply. This suggests that a simple heuristic description might be effective in the estimation of spin-kicks.
description: 12 pages, 10 figures. Replaced with published version, including more discussion of convergence and properties of final hole
Causal construction of the massless vertex diagram
Creators: name: Aste, Andreas
Publisher: name: arXiv
Year: 2006
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: The massless one-loop vertex diagram is constructed by exploiting the causal structure of the diagram in configuration space, which can be translated directly into dispersive relations in momentum space.
description: 14 pages, LATEX with style file, corresponds to published version
Universality class of isotropic on-lattice Eden clusters
Creators: name: Paiva, L. R.
name: Ferreira, S. C.
Publisher: name: arXiv
Year: 2006
Subjects: subject: Statistical Mechanics (cond-mat.stat-mech)
subject: FOS: Physical sciences

description: The shape of large on-lattice Eden clusters grown from a single seed is ruled by the underlying lattice anisotropy. This is reflected on the linear growth with time of the interface width ($w\sim t$), in contrast with the KPZ universality class ($w\sim t^{1/3}$) observed when the Eden model is grown on flat substrates. We propose an extended Eden model, in which the growth probability has a power law dependence with the number of occupied nearest neighbors. Large scale simulations ($N\gtrsim 4\times 10^9$ particles) were used to determine the time evolution of $w$. We found that a suitable choice of the power exponent removes the lattice-induced cluster anisotropy and provides a growth exponent in very good agreement with the KPZ universality class. Also, the present model corroborates the results found in off-lattice simulations, in which the center of mass fluctuations are considered in the interface scaling analysis.
description: To appear in J. Phys. A: Math. Gen
Second order necessary conditions in optimal control
Creators: name: Zheng, Harry H.
Publisher: name: University of British Columbia
Year: 2008

description: This thesis presents second order necessary conditions for the standard deterministic optimal control problem without conventional regularity assumptions. It reports three different advances in the second-order theory. First, we study conjugate points in smooth optimal control. We describe a set of conditions under which the second variation along an extremal trajectory is certain to be negative: when these are satisfied, they identify a certain point in the basic interval as a "Generalized Conjugate Point (GCP)." The GCP's include all conjugate points in the classical sense, and all points where the Legendre conditionis violated. We also find GCP's in many problems left unresolved by the published literature, and deduce that the associated extremals are not optimal. Second, we use a second-order tangent set to predict the second-order variations along a trajectory to a differential inclusion. Assuming only that the problem's data are Lipschitz continuous, we obtain a generalized form of the familiar statement that the second variation associated with a minimum point is nonnegative. The result is expressed in terms of a generalized second-order derivative introduced by Aubin, and reproduces the classical necessary conditions in the smooth case. Third, we apply Rockafellar's theory of epi-differentiability to integral functionals. Using At touch's theorem, we show that certain nonconvex integral functionals of interest in optimal control are twice epi-differentiable. From this we deduce necessary conditions for optimality for problems without endpoint constraints.
Noncommutative Prüfer rings and some generalizations
Creators: name: Zhou, Yiqiang
Publisher: name: University of British Columbia
Year: 2008

description: Noncommutative Prfifer rings appear naturally when one wants to transfer the known results for rings which arise in algebraic geometry (such as Dedekind, Krull and Priifer, valuation rings ...) to noncommutative rings. We remove the left-right symmetry condition of the noncommutative Prfifer rings introduced by Alajbegovic and Dubrovin, and introduce three natural generalizations, semi-Prfifer rings, right w-semi-Prfifer rings, and right w-Prfifer rings. We study the relations between the four concepts, and present the various properties that characterize them. We formulate and prove the basic facts for those rings (decompositions of such rings; Morita invariants of these notions; relations with some other notions). A new module-theoretic characterization of semiprime right Goldie rings is achieved by using the newly-defined concept of strongly compressible modules. The result is used to provide new characterizations of semiprime Goldie (prime right Goldie, or prime Goldie) rings, and right w-semi-Prfifer (semi-Prfifer, right w-Prfifer,or Prfifer) rings. In particular, the characterization of semiprime Goldierings of Lopez-Permouth, Rizvi, and Yousif using weakly-injective modules is an easy corollary of our results. We also study modules over noncommutative Priifer rings. It is shown that a module over a noncommutative Prfiferring has projective dimension at most one if and only if it is the union of a well-ordered continuous chain of submodules with each factor of the chain a finitely presented cyclic module. The result is used to present a characterization of divisible modules with projective dimension at most one over noncommutative Priifer rings, which generalizes a known result of L.Fuchs.
Non affine deformations and shape recovery in solids undergoing martensitic transformations
Creators: name: Bhattacharya, Jayee
name: Sengupta, Surajit
name: Rao, Madan
Publisher: name: arXiv
Year: 2008
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: Statistical Mechanics (cond-mat.stat-mech)
subject: FOS: Physical sciences

description: We study, using molecular dynamics simulations, the kinetics of shape recovery in a model solid undergoing transformations from square to a general rhombic lattice, the triangular lattice being included as a special case. We determine the necessary and sufficient conditions for such shape recovery in terms of the nature and dynamics of transient and localized {\em non-affine zones} which inevitably accompany the transformation.
description: 8 pages, 4 figures, higher resolution figures available on request
Stochastic Gross-Pitaevsky Equation for BEC via Coarse-Grained Effective Action
Creators: name: Calzetta, Esteban
name: Hu, B. L.
name: Verdaguer, Enric
Publisher: name: arXiv
Year: 2007
Subjects: subject: Statistical Mechanics (cond-mat.stat-mech)
subject: FOS: Physical sciences

description: We sketch the major steps in a functional integral derivation of a new set of Stochastic Gross-Pitaevsky equations (GPE) for a Bose-Einstein condensate (BEC) confined to a trap at zero temperature with the averaged effects of non-condensate modes incorporated as stochastic sources. The closed-time-path (CTP) coarse-grained effective action (CGEA) or the equivalent influence functional method is particularly suitable because it can account for the full back-reaction of the noncondensate modes on the condensate dynamics self-consistently. The Langevin equations derived here containing nonlocal dissipation together with colored and multiplicative noises are useful for a stochastic (as distinguished from say, a kinetic) description of the nonequilibrium dynamics of a BEC. This short paper contains original research results not yet published anywhere.
description: 6 pages
Ανάλυση Οικονομικών Επιπτώσεων Κυβερνοεπίθεσης σε Διεθνείς Οργανισμούς και Επιχειρήσεις & Μέθοδοι Προστασίας Προσωπικών Δεδομένων
Creators: name: Αειάντ, Ελαμίν Ζοχέρ
Publisher: name: Aristotle University of Thessaloniki
Year: 2020
Subjects: Κυβερνοασφάλεια
Κυβερνοεπιθέσεις
Προσωπικά δεδομένα
Cyber Security
Cyber Attacks
Personal Data

description: Οι επιθέσεις στον Κυβερνοχώρο είναι πλέον πολύ συνηθισμένες, σε μια εποχή που πλήθος συναλλαγών πραγματοποιούνται μέσω του Διαδικτύου. Τα «εγκλήματα» στον κυβερνοχώρο αυξάνονται συνεχώς, όπως και η ένταση των συνεπειών τους. Είναι κρίσιμο, λοιπόν να υπάρξει το απαραίτητο επίπεδο ασφάλειας, κατά των επιθέσεων στον κυβερνοχώρο, σε ένα κόσμο ο οποίος τείνει να γίνει όλο και πιο ψηφιακός. Στην παρούσα εργασία παρουσιάζεται η σημασία της ασφάλειας στον Κυβερνοχώρο, ενώ παρουσιάζονται και τα διάφορα είδη των Κυβερνοεπιθέσεων, καθώς και οι συνέπειες τους σε επιχειρήσεις και οργανισμούς. Επιπλέον, ιδιαίτερη μνεία γίνεται και στον Γενικό Κανονισμό Προστασίας Προσωπικών Δεδομένων», τα οποία συχνά αποτελούν το «λάφυρο» των επιθέσεων. Τέλος, παρουσιάζονται και τα αποτελέσματα σχετικής έρευνας σε δείγμα 235 ατόμων, καθώς και ένα μοντέλο το ordinal παλινδρόμησης το οποίο παρέχει τη δυνατότητα για εκτίμηση του κόστους αν είναι γνωστός ο όγκος των δεδομένων που χάθηκαν ή καταστράφηκαν και τον αριθμό των κυβερνοεπιθέσεων που δέχθηκε η εταιρεία ή ο οργανισμός το τελευταίο δωδεκάμηνο.
description: Cyber-attacks are now commonplace, at an era when many internet transactions are taking place. Cybercrime is constantly increasing, as is the intensity of its consequences. So, it is crucial to have the necessary level of security, against cyberattacks, in a world that is increasingly becoming digital. This paper presents the importance of cyber security, as well as the various types of cyberattacks, as well as their impact on businesses and organizations. In addition, special reference is made to the General Regulation on the Protection of Personal Data which is often the “target” of the Cyber attacks. Finally, the results of a survey of 235 people are presented, as well as a ordinal regression model that allows cost estimation if the amount of data lost or destroyed is known and the number of cyberattacks the company or organization has received over the last 12 months.
Flavor SU(3) analysis of charmless B meson decays to two pseudoscalar mesons
Creators: name: Chiang, Cheng-Wei
name: Zhou, Yu-Feng
Publisher: name: arXiv
Year: 2006
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: High Energy Physics - Experiment (hep-ex)
subject: FOS: Physical sciences

description: Global fits to charmless B --> PP decays in the framework of flavor SU(3) symmetry are updated and improved without reference to the \sin2βmeasured from the charmonium decay modes. Fit results directly constrain the (\barρ,\barη) vertex of the unitarity triangle, and are used to predict the branching ratios and CP asymmetries of all decay modes, including those of the B_s system. Different schemes of SU(3) breaking in decay amplitude sizes are analyzed. The major breaking effect between strangeness-conserving and strangeness-changing decays can be accounted for by including a ratio of decay constants in tree and color-suppressed amplitudes. The possibility of having a new physics contribution to K πdecays is also examined from the data fitting point of view.
description: 22 pages and 2 figures; some comments and references added; more references added, version to appear in journal
Generalized 2HDM with wrong-sign lepton Yukawa coupling, in light of $g_μ-2$ and lepton flavor violation at the future LHC
Creators: name: Ghosh, Nivedita
name: Lahiri, Jayita
Publisher: name: arXiv
Year: 2021
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: To explain the observed muon anomaly and simultaneously evade bounds from lepton flavor violation in the same model parameter space is a long cherished dream. In view of a generalized Two Higgs Doublet Model, with a Yukawa structure as a perturbation of Type-X, we are able to get substantial parameter space satisfying this criteria. We are focusing on a region with "{\bf wrong-sign}" lepton-Yukawa coupling which gives rise to an interesting phenomenological consequences. We found that in the "wrong-sign" region, it is possible to probe the low-mass pseudoscalar in flavor-violating decay mode with considerably better significance compared to the "right-sign" region. Performing a simple cut-based analysis we show that at 14 TeV run of the LHC with $300 fb^{-1}$ integrated luminosity, part of the model parameter space can be probed with significance $\geq 5σ$ which further improves with Artificial Neural Network analysis.
description: 26 Pages, 9 Figures, 4 Tables. Few references are added, draft is revised, version is accepted for publication in European Physical Journal C. arXiv admin note: text overlap with arXiv:2010.03590
Confinement from spontaneous breaking of scale symmetry
Creators: name: Gaete, Patricio
name: Guendelman, Eduardo
Publisher: name: arXiv
Year: 2006
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: We show that one can obtain naturally the confinement of static charges from the spontaneous symmetry breaking of scale invariance in a gauge theory. At the classical level a confining force is obtained and at the quantum level, using a gauge invariant but path-dependent variables formalism, the Cornell confining potential is explicitly obtained. Our procedure answers completely to the requirements by 't Hooft for ''perturbative confinement''.
description: 6 pages
Nationalistic and hate rhetoric in Greek internet media with the extensive use of disinformation practices and its influence in military/law enforcement personnel
Creators: name: Αναστασίου, Ευάγγελος Κωνσταντίνου
Publisher: name: Aristotle University of Thessaloniki
Year: 2020
Subjects: Σκόπιμη παραπληροφόρηση
Εθνικιστικός λόγος / ρητορική μίσους
Μέλη ελληνικών Ενόπλων Δυνάμεων / Σωμάτων Ασφαλείας
Disinformation
Nationalistic / hate rhetoric
Members of Greek military / law enforcement

description: This paper intents to research nationalistic and hate rhetoric occurrences in Greek internet media, enhanced by the use of fake news, and disinformation practices. It will mainly focus on specific websites with content related to national – internal security and defense, which are used as case studies. Through content analysis, conclusions are reached, whether the use of (proved to be) fake news, disinformation and nationalistic/hate rhetoric is a common practice which intends to attract viewers and thus increase the website(s) traffic and popularity. Furthermore, with the use of a questionnaire, I examine the level of acceptance and the influence of these websites to Greek citizens, focusing on those with a military/law enforcement background who follow these sites regularly or occasionally.
description: Η παρούσα εργασία, σκοπεύει να διερευνήσει περιπτώσεις εμφανίσεων εθνικιστικού περιεχομένου και ρητορικής μίσους στα ελληνικά διαδικτυακά μέσα ενημέρωσης, οι οποίες ενδυναμώνονται με τη χρήση ψευδών ειδήσεων και πρακτικών σκόπιμης παραπληροφόρησης. Θα εστιάσει κυρίως σε συγκεκριμένες ιστοσελίδες με περιεχόμενο σχετικό με την εθνική – εσωτερική ασφάλεια, οι οποίες και θα χρησιμοποιηθούν ως ερευνητικές βάσεις. Μέσω της ανάλυσης περιεχομένου, εξάγονται συμπεράσματα, εάν η χρήση (αποδεδειγμένα) ψευδών ειδήσεων, σκόπιμης παραπληροφόρησης, ρητορικής μίσους και εθνικιστικού λόγου, είναι κοινή πρακτική με πρόθεση την προσέλκυση αναγνωστών και την αύξηση κατ’ επέκταση της επισκεψιμότητας των υπόψη ιστοσελίδων. Επιπλέον, με τη χρήση ερωτηματολογίου εξετάζεται το επίπεδο αποδοχής των Ελλήνων πολιτών και επηρεασμού τους από τις ερευνόμενες ιστοσελίδες, εστιάζοντας σε αυτούς που προέρχονται από το περιβάλλον των Ενόπλων Δυνάμεων ή των Σωμάτων Ασφαλείας οι οποίοι και επισκέπτονται τακτικά ή περιστασιακά τις ιστοσελίδες αυτές.
Tomographic mapping of the hidden dimension in quasi-particle interference
Creators: name: Marques, C. A.
name: Bahramy, M. S.
name: Trainer, C.
name: Marković, I.
name: Watson, M. D.
name: Mazzola, F.
name: Rajan, A.
name: Raub, T. D.
name: King, P. D. C.
name: Wahl, P.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: Quasiparticle interference (QPI) imaging is well established to study the low-energy electronic structure in strongly correlated electron materials with unrivalled energy resolution. Yet, being a surface-sensitive technique, the interpretation of QPI only works well for anisotropic materials, where the dispersion in the direction perpendicular to the surface can be neglected and the quasiparticle interference is dominated by a quasi-2D electronic structure. Here, we explore QPI imaging of galena, a material with an electronic structure that does not exhibit pronounced anisotropy. We find that the quasiparticle interference signal is dominated by scattering vectors which are parallel to the surface plane however originate from bias-dependent cuts of the 3D electronic structure. We develop a formalism for the theoretical description of the QPI signal and demonstrate how this quasiparticle tomography can be used to obtain information about the 3D electronic structure and orbital character of the bands.
description: replaced by published version
Two Universal Extra Dimensions
Creators: name: Burdman, Gustavo
Publisher: name: arXiv
Year: 2006
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: We review the main results of the study of the Standard model propagating in two universal extra dimensions. Gauge bosons give rise to heavy spin-1 and spin-0 particles. The latter constitute the lightest Kaluza-Klein (KK) particle in the level (1,0). The level (1,1) can be s-channel produced. The main signals at the Tevatron and the LHC will be several $t\bar t$ resonances.
description: 4 pages, to appear in Proceedings of SUSY06, the 14th International Conference on Supersymmetry and the Unification of Fundamental Interactions, UC Irvine, California, 12-17 June 2006
Creativity (A Prepared PPT presentation for IGP on May 13, 2024 but was not shown and lectured due to some reason)
Creators: name: Dusaran, Ana Mae
Publisher: name: figshare
Year: 2024
Subjects: classificationCode: 360299
subject: Creative and professional writing not elsewhere classified

description: This PPT lecture presentation (converted to pdf) was supposed to be delivered and lectured on the 13th of May of 2024, but due to some reasons it did not happen. This information may be beneficial to those who can relate to it. This is all for God's glory.
Transcription of file 028_A (collection LA 256)
Creators: name: Parker, Verdena
name: Newbold, Lindsey
Publisher: name: California Language Archive, University of California, Berkeley
Year: 2022
Subjects: subject: hup

description: Audio files VP-170512-03 through VP-170512-06: Transcription of file 028_A (referred to here as 029_A) from LA 256 (a collection of recordings given to the Berkeley Language Center by Verdena), from 7:11 to 7:53 (VP-170512-03), from 7:53 to 9:00 (VP-170512-04), from 9:00 to 10:20 (VP-170512-05), and from 10:20 to 11:00 (VP-170512-06). The file was assigned a provisional identifier 029_A that was changed to 028_A in the final cataloging for the collection; file 028_A was subsequently assigned the identifier LA256.028A and associated with the bundle LA256.028 in the California Language Archive.
Πολιτισμικές καταβολές και παιδική εργασία: η περίπτωση των Ρομά στην Ελλάδα
Creators: name: Χάιτα, Μαρία Ηλία
Publisher: name: Aristotle University of Thessaloniki
Year: 2020
Subjects: Πολιτισμικές καταβολές
Ρομά
Παιδική εργασία
Cultural Background
Roma
Child labour

description: Σκοπός της διατριβής ήταν η μελέτη των πολιτισμικών καταβολών και κατά πόσο επηρεάζουν την παιδική εργασία. Η μελέτη εστιάζει στην παιδική εργασία στην Ελλάδα, και ειδικότερα στην εργασία των παιδιών Ρομά σε συνάρτηση με τις πολιτισμικές καταβολές τους. Εξετάζει τον ορισμό και τις μορφές της παιδικής εργασίας, τις θεωρίες που υπάρχουν και τις πολιτισμικές διαστάσεις του φαινομένου, την παρουσία της στην παραδοσιακή αλλά και στη σύγχρονη Ελλάδα, όπως και το νομικό πλαίσιο εντός και εκτός Ελλάδος. Ακόμα μελετάτε η εγκατάσταση των Ρομά στην Ελλάδα, η πολιτισμική τους ταυτότητα, η σχέση της παιδικής εργασίας με τη σχολική διαρροή και τέλος η εκπαίδευση που λαμβάνει η πολιτισμική αυτή ομάδα.
description: The aim of the present thesis was the study of cultural background and whether they affect child labour. The study focuses on child labor in Greece, and in particular on the work of Roma children in relation to their cultural backgrounds. It examines the definition and forms of child labor, the theories that exist and the cultural dimensions of the phenomenon, its presence in traditional and modern Greece, as well as the legal framework in Greece and also in the world. Yet, the present thesis studied the settlement of the Roma in Greece, their cultural identity, the relationship of child labor with school dropout and finally the education that this cultural group receives.
Variance of voltages in a lattice Coulomb gas
Creators: name: Conache, Diana
name: Heydenreich, Markus
name: Merkl, Franz
name: Rolles, Silke W. W.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Probability (math.PR)
subject: Mathematical Physics (math-ph)
subject: FOS: Mathematics
subject: FOS: Physical sciences
subject: 82B20 (Primary), 60K35 (Secondary)

description: We study the behavior of the variance of the difference of energies for putting an additional electric unit charge at two different locations in the two-dimensional lattice Coulomb gas in the high-temperature regime. For this, we exploit the duality between this model and a discrete Gaussian model. Our estimates follow from a spontaneous symmetry breaking in the latter model.
description: 12 pages, 1 figure
Coronal Properties of Low-mass Population III Stars and the Radiative Feedback in the Early Universe
Creators: name: Washinoue, Haruka
name: Suzuki, Takeru K.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: We systematically investigated the heating of coronal loops on metal-free stars with various stellar masses and magnetic fields by magnetohydrodynamic simulations. It is found that the coronal property is dependent on the coronal magnetic field strength $B_{\rm c}$ because it affects the difference of the nonlinearity of the Alfvénic waves. Weaker $B_{\rm c}$ leads to cooler and less dense coronae because most of the input waves dissipate in the lower atmosphere on account of the larger nonlinearity. Accordingly EUV and X-ray luminosities also correlate with $B_{\rm c}$, while they are emitted in a wide range of the field strength. Finally we extend our results to evaluating the contribution from low-mass Population III coronae to the cosmic reionization. Within the limited range of our parameters on magnetic fields and loop lengths, the EUV and X-ray radiations give a weak impact on the ionization and heating of the gas at high redshifts. However, there still remains a possibility of the contribution to the reionization from energetic flares involving long magnetic loops.
description: 11 pages, 5 figures. Accepted for publication in MNRAS
Quasi-Ballistic Thermal Conduction in 6H-SiC
Creators: name: Cheng, Zhe
name: Lu, Weifang
name: Shi, Jingjing
name: Tanaka, Daiki
name: Protik, Nakib H.
name: Wang, Shangkun
name: Iwaya, Motoaki
name: Takeuchi, Tetsuya
name: Kamiyama, Satoshi
name: Akasaki, Isamu
name: Amano, Hiroshi
name: Graham, Samuel
Publisher: name: arXiv
Year: 2021
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: The minimization of electronics makes heat dissipation of related devices an increasing challenge. When the size of materials is smaller than the phonon mean free paths, phonons transport without internal scatterings and laws of diffusive thermal conduction fail, resulting in significant reduction in the effective thermal conductivity. This work reports, for the first time, the temperature dependent thermal conductivity of doped epitaxial 6H-SiC and monocrystalline porous 6H-SiC below room temperature probed by time-domain thermoreflectance. Strong quasi-ballistic thermal transport was observed in these samples, especially at low temperatures. Doping and structural boundaries were applied to tune the quasi-ballistic thermal transport since dopants selectively scatter high-frequency phonons while boundaries scatter phonons with long mean free paths. Exceptionally strong phonon scattering by boron dopants are observed, compared to nitrogen dopants. Furthermore, orders of magnitude reduction in the measured thermal conductivity was observed at low temperatures for the porous 6H-SiC compared to the epitaxial 6H-SiC. Finally, first principles calculations and a simple Callaway model are built to understand the measured thermal conductivities. Our work sheds light on the fundamental understanding of thermal conduction in technologically-important wide bandgap semiconductors such as 6H-SiC and will impact applications such as thermal management of 6H-SiC-related electronics and devices.
Topics on critical point theory
Creators: name: Fang, Guangcai
Publisher: name: University of British Columbia
Year: 2008

description: Many questions in mathematics and physics can be reduced to the problem of finding and classifying the critical points of a suitable functional on an appropriate manifold. In this thesis, we will be concerned with the problems of existence, location and structure of critical points by building upon the well known min-max methods that are presently used in non-linear differential equations. The thesis consists of two parts: In the first part, we exploit the new powerful mountain pass principle of Ghoussoub and Preiss and its higher dimensional extensions by Ghoussoub to classify the critical points generated by Min-Max methods. The functionals under study are only assumed to be C1and therefore the classical Morse theory is not available. In order to do this, we isolate various topological indices that can be associated with certain critical sets and points. If the functionals are C2 and the critical points are non-degenerated, these indices can then be used to recover the standard results on Morse indices. The study in this direction was first initiated in the case of the mountain pass theorem by Hofer and was expanded later by Pucci-Serrin and Ghoussoub-Preiss. We shall extend and simplify all the previously obtained structural results in this setting, but more importantly, we consider the case of the saddle point theorem and various other higher dimensional settings. In the last part, we construct an almost critical sequence (xn). by min- max procedures for a C2-functional co on a Hilbert space with some Morse type information. Actually we obtain some analytical (second order) properties concerning the Hessian d2co(x,i) which can be viewed as the asymptotic version of the information on the Morse index of the limit of(x„)„ whenever such a limit exists. As noted by P.L. Lions in his studies of the Hartree-Fock equations for Coulomb systems, this type of additional information about an almost critical sequence can sometimes be crucial in the proof of its convergence and in solving the corresponding variational problems. Examples are given as applications of the general theory developed in the thesis.
Recoil Detection of the Lightest Neutralino in MSSM Singlet Extensions
Creators: name: Barger, Vernon
name: Langacker, Paul
name: Lewis, Ian
name: McCaskey, Mat
name: Shaughnessy, Gabe
name: Yencho, Brian
Publisher: name: arXiv
Year: 2007
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: We investigate the correlated predictions of singlet extended MSSM models for direct detection of the lightest neutralino with its cosmological relic density. To illustrate the general effects of the singlet, we take heavy sleptons and squarks. We apply LEP, $(g-2)_μ$ and perturbativity constraints. We find that the WMAP upper bound on the cold dark matter density limits much of the parameter space to regions where the lightest neutralino can be discovered in recoil experiments. The results for the NMSSM and UMSSM are typically similar to the MSSM since their light neutralinos have similar compositions and masses. In the n/sMSSM the neutralino is often very light and its recoil detection is within the reach of the CDMS II experiment. In general, most points in the parameter spaces of the singlet models we consider are accessible to the WARP experiment.
description: 30 pages, 11 figures
Transcription of file 021_A (collection LA 256)
Creators: name: Parker, Verdena
name: Escamilla, Ramón
Publisher: name: California Language Archive, University of California, Berkeley
Year: 2022
Subjects: subject: hup

description: Audio files VP-170512-02a/c: Transcription of file 021_A from LA 256 (a collection of recordings given to the Berkeley Language Center by Verdena), from the beginning of the file to 1:16. Due to re-numbering, tape 021_A has been assigned to the CLA item number LA256.021, audio file LA256.021A.
Proper time reparametrization in cosmology: Mobius symmetry and Kodama charges
Creators: name: Achour, Jibril Ben
Publisher: name: arXiv
Year: 2021
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: It has been noticed that for a large class of cosmological models, the gauge fixing of the time-reparametrization invariance does not completely fix the clock. Instead, the system enjoys a surprising residual Noether symmetry under a Möbius reparametrization of the proper time, which maps gauge-inequivalent solutions to the Friedman equations onto each other. In this work, we provide a unified treatment of this hidden conformal symmetry and its realization in the homogeneous and isotropic sector of the Einstein-Scalar-$Λ$ system. We consider the flat Friedmann-Robertson-Walker (FRW) model, the (A)dS cosmology and provide a first treatment of the model with spatial constant curvature. We derive the general condition relating the choice of proper time and the conformal weight of the scale factor, and give a detailed analysis of the conserved Noether charges generating this physical symmetry. Our approach allows us to identify new realizations of this symmetry while recovering previous results in a unified manner. We also present the general mapping onto the conformal particle and discuss the solution-generating nature of the transformations beyond the Möbius symmetry. Finally, we show that, at least in a restricted context, this hidden conformal symmetry is intimately related to the Kodama charges of spherically symmetric gravity. This new connection suggests that the Möbius invariance of cosmology is only the corner of a larger symmetry structure which could be relevant beyond cosmological models.
description: 34 pages, matched the published version in JCAP
Πρωτοπαθής Προϊούσα Αφασία & Πρωτοπαθής Προϊούσα Απραξία του Λόγου- βιβλιογραφική ανασκόπηση και μελέτη 2 περιστατικών
Creators: name: Γκούτη, Φωτεινή Σταύρου
Publisher: name: Aristotle University of Thessaloniki
Year: 2020
Subjects: Πρωτοπαθής Προϊούσα Αφασία
Πρωτοπαθής Προϊούσα Απραξία του Λόγου
Μελέτη Περιπτώσεων
Primary Progressive Aphasia
Primary Progressive Apraxia of Speech
Case Study

description: Η Πρωτοπαθής Προϊούσα Αφασία αποτελεί μια νόσο η οποία έχει αρχίσει να ερευνάται τις τελευταίες δεκαετίες. Ανήκει στην ομπρέλα των ανοιακών νοσημάτων και η έναρξη αυτής της νόσου είναι τυχαία και χωρίς συγκεκριμένη αιτιολογία. Η Πρωτοπαθής Προϊούσα Απραξία του Λόγου αποτελεί ένα παρόμοιο σύνδρομο το οποίο ανακαλύφθηκε πολύ πιο πρόσφατα και παρουσιάζει μικρή συχνότητα εμφάνισης. Η παρούσα εργασία αποτελεί την βιβλιογραφική ανασκόπηση των δυο αυτών νευροεκφυλιστικών νοσημάτων και την συνοπτική παρουσίαση 2 περιστατικών που διαγνώστηκαν ως πάσχοντες με Πρωτοπαθή Προϊούσα Αφασία. Το 1ο μέρος είναι το γενικό μέρος με τα ευρήματα άλλων ερευνών και το 2ο μέρος αποτελεί το ειδικό μέρος, την έρευνα επάνω στα 2 αυτά περιστατικά.
description: Primary Progressive Aphasia is a disease that has begun to be investigated in recent decades. It belongs to the umbrella of dementia and the onset of this disease is accidental and without specific reason. Primary Progressive Apraxia of Speech is a similar syndrome that has been discovered more recently and has a low incidence. The present work is a review of these two neurodegenerative diseases and a brief presentation of 2 cases diagnosed with Primary Progressive Aphasia. The first part is the general part with the findings of other investigations and the second part is the special part, the investigation on these two incidents.
Thermal dynamics and electronic temperature waves in layered correlated materials
Creators: name: Mazza, Giacomo
name: Gandolfi, Marco
name: Capone, Massimo
name: Banfi, Francesco
name: Giannetti, Claudio
Publisher: name: arXiv
Year: 2021
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: We explore layered strongly correlated materials as a platform to identify and control unconventional heat transfer phenomena. We demonstrate that these systems can be tailored to sustain a wide spectrum of heat transport regimes, ranging from ballistic, to hydrodynamic all the way to diffusive. Within the hydrodynamic regime, wave-like temperature oscillations are predicted up to room temperature. All the above phenomena have a purely electronic origin, stemming from the existence of two components in the electronic system, each one thermalized at different temperatures. The interaction strength can be exploited as a knob to control the different thermal transport regimes. The present results pave the way to transition-metal oxide heterostructures as building blocks for nanodevices exploiting the wave-like nature of heat transfer on the picosecond time scale.
description: 12 pages and 6 figures + Supplementary Information
Evolution or degeneration? Darwin’s influence on R.L. Stevenson’s Strange case of Dr. Jekyll and Mr. Hyde and H.P. Lovecraft’s “The shadow over Innsmouth”
Creators: name: Καραγιάννης, Δημήτριος Γεωργίου
Publisher: name: Aristotle University of Thessaloniki
Year: 2020
Subjects: Δαρβίνος
Εξέλιξη
Εκφυλισμός
Darwin
Evolution
Degeneration

description: Charles Darwin’s evolution theory, which he analyzes in On the Origin of Species (1859), as well as The Descent of Man, And Selection Related to Sex (1871), fundamentally shook all pillars of human life, including science and culture. This thesis explores the palpable influence of Darwin and science on two literary works separated both temporally and geographically: R. L. Stevenson’s Strange Case of Dr. Jekyll and Mr. Hyde, published in England at 1886, and H.P. Lovecraft’s “The Shadow over Innsmouth,” published in 1936 in the United States of America. A careful comparison of these two Gothic texts indicates the existence of multiple links and similarities between them which are articulated under the strong and evident influence of Darwin’s evolution theory. The tantalizing difference between human evolution and degeneration, a topic much stirred by Darwin’s theory, can be singled out as the most noteworthy theme that both of these literary works approach. At the same time, the social background of both late Victorian England and the United States up until the late 1920s is compared and contrasted with regards to how both societies processed the implications and complications of Darwin’s evolution theory.
description: Η θεωρία της εξέλιξης του Κάρολου Δαρβίνου, όπως την αναλύει στο βιβλίο Η Καταγωγή των Ειδών (1859), καθώς και στο βιβλίο Η Καταγωγή του Ανθρώπου (1871), ταρακούνησε όλους τους πυλώνες της ανθρώπινης ζωής, και ειδικότερα την επιστήμη και την κουλτούρα. Αυτή η διπλωματική εργασία εξερευνά την αισθητή επιρροή του Δαρβίνου και της επιστήμης σε δύο λογοτεχνικά έργα διαχωρισμένα και χρονικά και γεωγραφικά: Την Παράξενη Υπόθεση του Δόκτωρ Τζέκιλ και του Κύριου Χάιντ από τον Ρόμπερτ Λούις Στίβενσον, δημοσιευμένη για πρώτη φορά στην Αγγλία του 1886, και την «Σκιά πάνω από το Ίνσμουθ» του Χάουαρντ Φίλλιπς Λόβκραφτ, δημοσιευμένη το 1936 στις Ηνωμένες Πολιτείες της Αμερικής. Μια προσεκτική σύγκριση των δύο αυτών γοτθικών κειμένων αναδεικνύει την ύπαρξη πολλαπλών συνδέσεων και ομοιοτήτων αναμεταξύ τους, οι οποίες αρθρώνονται μέσα από την έκδηλη, δυνατή επιρροή της θεωρίας της εξέλιξης των ειδών του Δαρβίνου. Η σχεδόν σαγηνευτική διαφορά ανάμεσα στην ανθρώπινη εξέλιξη και τον εκφυλισμό, ένα θέμα που αβίαστα προερχόταν από την θεωρία του Δαρβίνου, μπορεί να απομονωθεί ως το πιο σημαντικό θέμα που και τα δύο αυτά λογοτεχνικά έργα προσεγγίζουν. Ταυτόχρονα, το κοινωνικό γίγνεσθαι της Βικτωριανής Αγγλίας και των Ηνωμένων Πολιτειών μέχρι τα τέλη της δεκαετίας του 1920 συγκρίνεται και αξιολογείται γύρω από το πώς και οι δύο αυτές κοινωνίες επεξεργάστηκαν τις περιπλοκότητες και τα αποτελέσματα, υπονοούμενα και μη, της θεωρίας της εξέλιξης των ειδών του Δαρβίνου.
First broad band study of the mysterious source 1E 1743.1-2843
Creators: name: Del Santo, M.
name: Sidoli, L.
name: Bazzano, A.
name: Cocchi, M.
name: De Cesare, G.
name: Paizis, A.
name: Ubertini, P.
Publisher: name: arXiv
Year: 2006
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: In the last years, the persistent source 1E 1743.1-2843 has been observed in the X-rays, but never above 20 keV. In previous works, it was stressed that a possible high energy emission could give further indications on the accreting object nature which remains still unknown. We present here more than two years of 1E 1743.1-2843 monitoring with INTEGRAL/IBIS as well as public XMM-Newton and Chandra X-ray observations. The temporal study in the 20-40 keV band shows a rather constant flux on few months time scale. Based on this result we have performed the broad-band spectral analysis using EPIC/IBIS non simultaneous data and ACIS-I/IBIS data collected during 2004. In ~2 Ms, we report a detection of 6 sigma in the energy range 35-70 keV. The first broad-band study (2-70 keV) shows a steep slope (~3) and a black body temperature of 1.7 keV. Combining spectral parameters and discussion about the luminosity evaluations for different possible distances, our conclusions are in favour of a LMXB system with a neutron star at distance higher than the Galactic Centre, even though a firm conclusion can not be stated.
description: 4 pages, 3 figures, accepted for publication in A&A
Μετάφραση και Επιχώρια Προσαρμογή Τουριστικών Κειμένων: Κείμενα ΕΟΤ
Creators: name: Καρακώστα, Ανθή Δημητρίου
Publisher: name: Aristotle University of Thessaloniki
Year: 2020
Subjects: Επιχώρια προσαρμογή διαδικτυακών τόπων
Υπερχώρια προσαρμογή
Τουριστικό κείμενο
Website localization
Universalization
Tourist text

description: Η παρούσα πτυχιακή εργασία έχει ως στόχο τη μελέτη του φαινομένου νέας επιχώριας προσαρμογής στα τουριστικά κείμενα. Πιο συγκεκριμένα, θα αναλυθούν και διερευνηθούν οι όροι μετάφραση, επιχώρια προσαρμογή και τουριστικό κείμενο, βάσει βιβλιογραφικών πηγών. Επιπλέον, θα αναφερθούμε στην ιδιάζουσα περίπτωση νέας «υπερχώριας προσαρμογής», νέας ορίζεται από νέας Φλώρο και Χαραλαμπίδου. Στη συνέχεια, θα παρουσιάσουμε μια μελέτη περίπτωσης, όπου θα μελετηθούν επιλεγμένα κείμενα από την επίσημη ιστοσελίδα του ΕΟΤ (visitgreece.gr), τα οποία έχουν συνταχθεί με σκοπό να παρουσιάσουν και να προωθήσουν τον ελληνικό πολιτισμό και τη χώρα νέας. Θα μελετηθούν οι ομοιότητες και οι διαφορές που παρουσιάζουν τα ελληνικά πρωτότυπα κείμενα με τα μεταφράσματά νέας στα αγγλικά. Η μελέτη περιστρέφεται γύρω από τη θεωρία του σκοπού και το κατά πόσο επιτυγχάνεται η λειτουργικότητα των εν λόγω κειμένων και των επιμέρους στοιχείων του ανάλογα με τον πολιτισμό-στόχος. Η σύγκριση αφορά σε κείμενα παρμένα από τον τομέα του πολιτισμού και νέας γαστρονομίας και θα πραγματοποιηθεί σε σημασιολογικό, πολιτισμικό και μορφολογικό επίπεδο. Παράλληλα, θα ληφθεί υπόψη και η πολυμεσικότητα που διέπει νέας ιστοτόπους όπου είναι αναρτημένα τα ψηφιακά κείμενα, καθώς περιλαμβάνουν γραπτό λόγο, εικόνες, βίντεο, κ.ά.
description: ABSTRACT The aim of the present thesis is the study of localization in tourist texts. In particular, the terms translation, localization and tourist text will be analyzed and explored, based on bibliographical references. In addition, we will refer to the particular case of “universalization”, as defined by Floros and Charalambidou. Then, we will present a case study, in which we will explore and analyze selected texts taken from the official website of Greek National Tourism Organization (visitgreece.gr). The texts have been written in order to present and promote Greek culture and our country. The similarities and differences between the Greek source texts and their translations into English will be studied. The study revolves around the skopos theory and the extent to which the functionality of these texts and their sub-elements is achieved, given the target culture. The comparative analysis involves cultural and gastronomical texts and will be carried out at a semantic, cultural and morphological level. In addition, the multimediality that governs the websites where digital texts are posted will also be taken into account, as the sites include written discourse, images, videos, and more.