cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Coupling mesoscale-microscale models for characterising the wind flow in complex terrain
Creators: name: Asmae, El Bahlouli
name: Knaus Hermann
name: Leukauf Daniel
name: Zum Berge Kjell
Publisher: name: Zenodo
Year: 2019

description: Coupling a mesoscale model to a microscale model which presents a more detailed representation of the topography is one of the promising approaches for wind energy assessment in complex terrain. In our study, the mesoscale flow is simulated by the Weather Research and Forecasting (WRF) model. Then, the microscale simulations are conducted with inflow conditions acquired from the mesoscale model. The latter provides data such as temperature, pressure, velocity or humidity at the lateral and top boundaries of the microscale domain (10 km x 10 km x 2 km) every 1 minute. The microscale model, implemented into the open source toolbox OpenFOAM, is based on an unsteady Reynolds averaged Navier-Stokes (URANS) approach with a modified version of the standard k-ε model. The proposed coupling method is applied to the Wind Science and Engineering in Complex Terrain (WINSENT) field-test site in the Swabian Alps in Southern Germany. The main feature of the site is a vegetated escarpment up to 200 m height with respect to the valley. The site shows a predominant yearly wind direction westward making the test site interesting in the sense that the wind is perpendicular to the escarpment. The WINSENT test site is equipped with several measurement systems, like eddy-covariance micro-meteorological stations, towers equipped with sonic and propeller anemometers. The numerical simulations are compared to tower data and measurements performed by an unmanned aircraft systems (UAS). Preliminary results from the numerical simulations show the potential of the coupling method and satisfactory results in reproducing some interesting flow features .
Solar system constraints on multi-field theories of modified dynamics
Creators: name: Sanders, R. H.
Publisher: name: arXiv
Year: 2006
Subjects: subject: Astrophysics (astro-ph)
subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: Any viable theory of modified Newtonian dynamcs (MOND) as modified gravity is likely to require fields in addition to the usual tensor field of General Relativity. For such theories the MOND phenomenology emerges from an effective fifth force probably associated with a scalar field. Here I consider the constraints imposed upon such theories by solar system phenomenology, primarily by the absence of significant deviations from inverse square attraction in the inner solar system as well as detectable local preferred frame effects. The current examples of multi-field theories can be constructed to satisfy these constraints and such theories lead inevitably to an anomalous non inverse-square force in the outer solar system.
description: 11 pages, 6 figures, submitted MNRAS, revised in response to referee, improved clarity, one figure added, additional references
A Winning Approach for Airports To Enhance Revenues and Passenger Satisfaction Using the Six Sigma Philosophy
Creators: name: Anantharaman, Senthil Kumar
Publisher: name: Zenodo
Year: 2017

description: Six Sigma in airport operations is yet to gain substantial benefits when compared to its application in other sectors like manufacturing, financial services, telecommunication services, Information Technology based services and Healthcare services. One of the root causes that this methodology has not been able to reap great benefits in airport sector is that this has been overpowered by its competing process improvement techniques like Theory of Constraints, Lean and Kaizen. In this study, we discuss about some of the key projects and areas in the airport sector, both in aero and non-aero areas of the airport that can be highly assisted by applying Six Sigma along with other process improvement techniques. While the airports which we have considered, is primarily in India and run by private operators in PPP setup, the methodology can be applied equally well in public sector operated airports. This study also compares the revenues that can arise out of opportunities, that Six Sigma as a philosophy and methodology can provide to the airport sector, if applied with vigour and robustness. Further the paper also comes out with a winning approach of combining Six Sigma methodology with Kaizen, Lean and Theory of Constraints in a way that will be feasible for the top management of the airports to enhance the revenues while providing the passengers a delightful experience.
Quasi-linear theory of forced magnetic reconnection for the transition from linear to Rutherford regime
Creators: name: Huang, Wenlong
name: Zhu, Ping
Publisher: name: arXiv
Year: 2020
Subjects: subject: Plasma Physics (physics.plasm-ph)
subject: FOS: Physical sciences

description: Using the in-viscid two-field reduced MHD model, a new analytical theory is developed to unify the Hahm-Kulsrud-Taylor (HKT) linear solution and the Rutherford quasi-linear regime. Adopting a quasi-linear approach, we obtain a closed system of equations for plasma response in a static plasma in slab geometry. An integral form of analytical solution is obtained for the forced magnetic reconnection, uniformly valid throughout the entire regimes from the HKT linear solution to the Rutherford quasi-linear solution. In particular, the quasi-linear effect can be described by a single coefficient $K_s\propto S^{8/5} ψ_c^2$, where $S=\frac{τ_R}{τ_A}$ and $ψ_c$ are the Lunquist number and amplitude of external magnetic perturbation, respectively. The HKT linear solution for response can be recovered when the index $K_s\rightarrow 0$. On the other hand, the quasi-linear effect plays a key role in the island growth when $K_s\sim1$. Our new analytical solution has also been compared with reduced MHD simulations with agreement.
Η Μέθοδος του Εκπαιδευτικού Δράματος στα Λαϊκά Παραμύθια:
Creators: name: Μπατάνη, Μαρία Γρηγορίου
Publisher: name: Aristotle University of Thessaloniki
Year: 2012
Subjects: Εκπαιδευτικό
Θέατρο
Παραμύθια
Drama
Theatre
Folktales

description: Στην εργασία που ακολουθεί γίνεται μια προσπάθεια να έρθει ο αναγνώστης σε επαφή με την δημιουργία και την εξέλιξη τόσο του Εκπαιδευτικού Δράματος όσο και του Λαϊκού Παραμυθιού. Από τη μια πλευρά στόχος είναι να γνωρίσει τις βασικές αρχές και τεχνικές του Εκπαιδευτικού Δράματος αλλά και να κατανοήσει τα οφέλη που αποκομίζουν τα παιδιά από τη συμμετοχή τους σ’ αυτό. Σε αυτή ακριβώς την παιδαγωγική αξία θα εστιάσουμε και στην ανάλυση του Λαϊκού Παραμυθιού. Ωστόσο, θα ερευνήσουμε αρχικά την δημιουργία και την εξάπλωσή του τόσο παγκόσμια όσο και στον ελλαδικό χώρο. Και μέσα από την προφορική παράδοση και τις αφηγηματικές τεχνικές που θα αναλυθούν, θα αναζητήσουμε την παιδαγωγική αξία των παραμυθιών. Επιπροσθέτως, τα Λαϊκά Παραμύθια γίνονται το βασικό ερέθισμα για την δημιουργία ενός Εκπαιδευτικού Δράματος καθώς η μελέτη στρέφεται στους κοινούς στόχους του Δράματος και του Παραμυθιού και κατά πόσο αυτοί μπορούν να επιτευχθούν από την συνύπαρξη των δύο ειδών .
description: In the framework of the following research, an attempt takes place targeting the reader to make contact with the generation and the development of the Drama in Education and the Folktale as well. On one side, the main aim will be the knowledge of the primary principles and the techniques of the Drama in Education, but also the comprehension of the benefits that the children obtain by their participation in them. So we will focus on this specific pedagogic value and the Folktale analysis. However, firstly we will study on its generation and spread universally and in Greek area, too. Eventually, the oral tradition and the narrative techniques analysis will lead us to search for the pedagogic value of the folktales. In addition, the Folktales are the essential stimulus for the Drama in Education generation, as long as the research turns to the usual goals of Drama and the Folktale and if they are possibly implemented by the coexistence of the two genres.
Analysis and Assembling of Network Structure in Mutualistic Systems
Creators: name: Medan, Diego
name: Perazzo, Roberto P. J.
name: Devoto, Mariano
name: Burgos, Enrique
name: Zimmermann, Martin G.
name: Ceva, Horacio
name: Delbue, Ana M.
Publisher: name: arXiv
Year: 2007
Subjects: subject: Populations and Evolution (q-bio.PE)
subject: FOS: Biological sciences

description: It has been observed that mutualistic bipartite networks have a nested structure of interactions. In addition, the degree distributions associated with the two guilds involved in such networks (e.g. plants & pollinators or plants & seed dispersers) approximately follow a truncated power law. We show that nestedness and truncated power law distributions are intimately linked, and that any biological reasons for such truncation are superimposed to finite size effects . We further explore the internal organization of bipartite networks by developing a self-organizing network model (SNM) that reproduces empirical observations of pollination systems of widely different sizes. Since the only inputs to the SNM are numbers of plant and animal species, and their interactions (i.e., no data on local abundance of the interacting species are needed), we suggest that the well-known association between species frequency of interaction and species degree is a consequence rather than a cause, of the observed network structure.
description: J. of. Theor. Biology, in press
Optimal Order of Decoding for Max-Min Fairness in $K$-User Memoryless Interference Channels
Creators: name: Maddah-Ali, Mohammad Ali
name: Mahdavi-Doost, Hajar
name: Khandani, Amir K.
Publisher: name: arXiv
Year: 2007
Subjects: subject: Information Theory (cs.IT)
subject: FOS: Computer and information sciences

description: A $K$-user memoryless interference channel is considered where each receiver sequentially decodes the data of a subset of transmitters before it decodes the data of the designated transmitter. Therefore, the data rate of each transmitter depends on (i) the subset of receivers which decode the data of that transmitter, (ii) the decoding order, employed at each of these receivers. In this paper, a greedy algorithm is developed to find the users which are decoded at each receiver and the corresponding decoding order such that the minimum rate of the users is maximized. It is proven that the proposed algorithm is optimal.
description: 11 Pages, Submitted to IEEE International Symposium on Information Theory(ISIT 2007)
Deductive Systems and Coherence for Skew Prounital Closed Categories
Creators: name: Uustalu, Tarmo
name: Veltri, Niccolò
name: Zeilberger, Noam
Publisher: name: arXiv
Year: 2021
Subjects: subject: Logic in Computer Science (cs.LO)
subject: Category Theory (math.CT)
subject: FOS: Computer and information sciences
subject: FOS: Mathematics

description: In this paper, we develop the proof theory of skew prounital closed categories. These are variants of the skew closed categories of Street where the unit is not represented. Skew closed categories in turn are a weakening of the closed categories of Eilenberg and Kelly where no structural law is required to be invertible. The presence of a monoidal structure in these categories is not required. We construct several equivalent presentations of the free skew prounital closed category on a given set of generating objects: a categorical calculus (Hilbert-style system), a cut-free sequent calculus and a natural deduction system corresponding to a variant of planar (= non-commutative linear) typed lambda-calculus. We solve the coherence problem for skew prounital closed categories by showing that the sequent calculus admits focusing and presenting two reduction-free normalization procedures for the natural deduction calculus: normalization by evaluation and hereditary substitutions. Normal natural deduction derivations (beta-eta-long forms) are in one-to-one correspondence with derivations in the focused sequent calculus. Unexpectedly, the free skew prounital closed category on a set satisfies a left-normality condition which makes it lose its skew aspect. This pitfall can be avoided by considering the free skew prounital closed category on a skew multicategory instead. The latter has a presentation as a cut-free sequent calculus for which it is easy to see that the left-normality condition generally fails. The whole development has been fully formalized in the dependently typed programming language Agda.
description: In Proceedings LFMTP 2020, arXiv:2101.02835
Unresolved problems in superconductivity of CaC6
Creators: name: Mazin, I. I.
name: Boeri, L.
name: Dolgov, O. V.
name: Golubov, A. A.
name: Bachelet, G. B.
name: Giantomassi, M.
name: Andersen, O. K.
Publisher: name: arXiv
Year: 2006
Subjects: subject: Superconductivity (cond-mat.supr-con)
subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: We discuss the current status of the theory of the "high-temperature" superconductivity in intercalated graphites YbC6 and CaC6. We emphasize that while the general picture of conventional, phonon-driven superconductivity has already emerged and is generally accepted, there are still interesting problems with this picture, such as weak-coupling regime inferred from specific heat suggesting coupling exclusively with high-energy carbon phonons coming in direct contradiction with the isotope effect measurements suggesting coupling exclusively with the low-energy intercalant modes. At the same time, the first principle calculations, while explaining Tc, contradict both of the experiments above by predicting equal coupling with both groups of phonons.
description: Contribution to the Proceedings of the M2S Conference in Dresden, 2006
Bond algebraic liquid phase in strongly correlated multiflavor cold atom systems
Creators: name: Xu, Cenke
name: Fisher, Matthew P. A.
Publisher: name: arXiv
Year: 2006
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: Soft Condensed Matter (cond-mat.soft)
subject: FOS: Physical sciences

description: When cold atoms are trapped in a square or cubic optical lattice, it should be possible to pump the atoms into excited $p-$level orbitals within each well. Following earlier work, we explore the metastable equilibrium that can be established before the atoms decay into the $s-$wave orbital ground state. We will discuss the situation with integer number of bosons on every site, and consider the strong correlation "insulating" regime. By employing a spin-wave analysis together with a new duality transformation, we establish the existence and stability of a novel gapless "critical phase", which we refer to as a "bond algebraic liquid". The gapless nature of this phase is stabilized due to the emergence of symmetries which lead to a quasi-one dimensional behavior. Within the algebraic liquid phase, both bond operators and particle flavor occupation number operators have correlations which decay algebraically in space and time. Upon varying parameters, the algebraic bond liquid can be unstable to either a Mott insulator phase which spontaneously breaks lattice symmetries, or a $\mathbb{Z}_2$ phase. The possibility of detecting the algebraic liquid phase in cold atom experiments is addressed. Although the momentum distribution function is insufficient to distinguish the algebraic bond liquid from other phases, the density correlation function can in principle be used to detect this new phase of matter.
description: 15 pages, 10 figures
A Dusty Disk Around WD1150-153: Explaining the Metals in White Dwarfs by Accretion from the Interstellar Medium versus Debris Disks
Creators: name: Kilic, Mukremin
name: Redfield, Seth
Publisher: name: arXiv
Year: 2007
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: We report the discovery of excess K-band radiation from a metal-rich DAV white dwarf star, WD1150-153. Our near infrared spectroscopic observations show that the excess radiation cannot be explained by a (sub)stellar companion, and is likely to be caused by a debris disk similar to the other DAZ white dwarfs with circumstellar debris disks. We find that the fraction of DAZ white dwarfs with detectable debris disks is at least 14%. We also revisit the problem of explaining the metals in white dwarf photospheres by accretion from the interstellar medium (ISM). We use the observed interstellar column densities toward stars in close angular proximity and similar distance as DAZ white dwarfs to constrain the contribution of accretion from the ISM. We find no correlation between the accretion density required to supply metals observed in DAZs with the densities observed in their interstellar environment, indicating that ISM accretion alone cannot explain the presence of metals in nearby DAZ white dwarfs. Although ISM accretion will certainly contribute, our analysis indicates that it is not the dominant source of metals for most DAZ white dwarfs. Instead, the growing number of circumstellar debris disks around DAZs suggests that circumstellar material may play a more dominant role in polluting the white dwarf atmospheres.
description: ApJ, in press
Third order Coulomb correction to ttbar threshold cross section
Creators: name: Kiyo, Y.
Publisher: name: arXiv
Year: 2006
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: We report on our result of third order Coulomb correction to the cross section sigma(ee -> ttbar) near threshold. Analytic expression for the Coulomb energy and wave function at the origin are obtained. We discuss the significance of the Coulomb correction to the threshold cross section and heavy quarkonium phenomenology.
description: To appear in the proceedings of the 7th International Symposium on Radiative Corrections(RADCOR05), Shonan Village, Japana Oct. 2005
LambdaCDM Halo Density Profiles: where do actual halos converge to NFW ones?
Creators: name: Gentile, Gianfranco
name: Tonini, Chiara
name: Salucci, Paolo
Publisher: name: arXiv
Year: 2007
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: Aims. We present an analysis of 37 high-quality extended rotation curves that highlights the existence of a new discrepancy (or a new aspect of an old discrepancy) between the density profiles predicted by the Lambda Cold Dark Matter (LambdaCDM) theory and the actual distribution of dark matter in galaxies. Methods. We compare the predicted face-value density vs. enclosed mass relationship, at large distances, to the observational data at the last measured radii of the rotation curves and in two whole rotation curves of high quality. A further analysis is performed by studying a relation, inbuilt in LambdaCDM, that links at radius R, the enclosed halo mass M(R) and its density rho(R) in a way that is independent of the mass of the virialised object. Results. We find that the predicted density vs. enclosed mass relationship has a systematic offset with respect to the observational data. In test case extended rotation curves, at their last measured point, the predicted NFW densities are up to a factor 3 lower than those derived from the kinematics. Moreover, the abovementioned relation, inbuilt in LambdaCDM, does not hold for the objects of our sample. Such a new outer discrepancy is different and maybe complementary with respect to the core/cusp issue, for which the NFW densities turn out to be higher than those observed and it seems to imply a global mass rearrangement of a pristine NFW-LambdaCDM halo.
description: Accepted for publication in A&A. 9 pages, 6 figures (2 in colour)
Fast ejecta as a potential way to distinguish black holes from neutron stars in high-mass gravitational-wave events
Creators: name: Most, Elias R.
name: Papenfort, L. Jens
name: Tootle, Samuel
name: Rezzolla, Luciano
Publisher: name: arXiv
Year: 2020
Subjects: subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: High-mass gravitational-wave events in the neutron-star mass range, such as GW190425, have recently started to be detected by the LIGO/Virgo detectors. If the masses of the two binary components fall in the neutron-star mass range, such a system is typically classified as a binary neutron-star system, although the detected gravitational-wave signal may be too noisy to clearly establish a neutron-star nature of the high-mass component in the binary and rule out a black hole--neutron star system for such an event. We here show that high-mass binary neutron-star mergers with a very massive neutron-star primary close to the maximum-mass limit, $m_1 \gtrsim 2.2 \, M_\odot$, produce fast dynamical mass ejecta from the spin-up of the primary star at merger. By simulating the merger of black hole--neutron star systems of exactly the same masses and spins, we show that these fast ejecta are entirely absent, if the primary is instead a black hole. In addition, we find that both systems leave almost identical amounts of baryon mass behind, which is not immediately accreted by the black hole. This implies that both systems will likely have comparable electromagnetic afterglow emission stemming from the remnant disk. Hence, fast ejecta at merger have the potentialto distinguish neutron stars from black holes in high-mass mergers, although these ejecta may be challenging to detect observationally.
description: 15 pages, 8 figures, 2 tables
Η αξιοποίηση των 3D Εικονικών Κόσμων στην Εκπαίδευση
Creators: name: Αποστόλου, Ελευθερία Αποστόλου
Publisher: name: Aristotle University of Thessaloniki
Year: 2012
Subjects: Εικονικοί Κόσμοι
Τρισδιάστατος
Εκπαίδευση
Virtual Worlds
3D
Education

description: Αντικείμενο της παρούσας εργασίας είναι η μελέτη της εφαρμογής των 3D εικονικών κόσμων στην εκπαίδευση. Στο πλαίσιο αυτό εξετάζονται οι έννοιες της μάθησης και της εκπαίδευσης, των τεχνολογιών της Πληροφορίας και των Επικοινωνιών και η εφαρμογή τους στην εκπαιδευτική διαδικασία. Περιγράφονται μεθοδολογίες διδασκαλίας με τη χρήση υπολογιστή, η συνεργατική μάθηση, το e-learning και η παιχνιδοκεντρική μάθηση. Αναλύεται η έννοια των 3D εικονικών κόσμων, η εξέλιξη και τα χαρακτηριστικά τους και εξετάζεται ο τρόπος, τα πλεονεκτήματα και τα μειονεκτήματα της χρήσης τους στα πλαίσια της εκπαιδευτικής διαδικασίας. Εξετάζονται παραδείγματα από την εφαρμογή των 3D εικονικών κόσμων με βάση ορισμένα κριτήρια, πιο συγκεκριμένα με βάση το target group όπου εξετάζονται θέματα βαθμίδων εκπαίδευσης, εκπαιδευτικών και ειδικής αγωγής, με βάση την μεθοδολογία, όπου εξετάστηκαν θέματα συνεργατικής μάθησης, e-learning και παιχνιδοκεντρικής μάθησης και με βάση το γνωστικό αντικείμενο, όπου εξετάστηκαν θέματα εφαρμογής σε διάφορους επιστημονικούς τομείς, από την αρχαιολογία μέχρι τις θετικές επιστήμες και την αστρονομία. Στη συνέχεια γίνεται μια αποτίμηση των εφαρμογών αυτών για να εξεταστεί κατά πόσο η εφαρμογή των 3D εικονικών κόσμων είναι θετική στην εκπαίδευση.
description: The purpose of this paper is to study the application of 3D virtual worlds in education. Within this context, the concepts of learning and education, information technology and communication and their application in the educational process, will be considered. Methods of teaching using a computer, collaborative learning, e-learning and game-based learning will be analysed. The concept of 3D virtual worlds, their evolution and characteristics are discussed, as well as what their advantages and disadvantages are by their use in the educational process. Specific examples from the application of 3D virtual worlds based on certain criteria, most notably by target group which examines issues of educational levels, educational and special education, by the methodology, which examined issues of collaborative learning, e-learning and learning and game-based learning and by the subject and the implementation issues in various disciplines, from archeology to science and astronomy, are discussed in detail. Finally, an assessment of these applications is done in order to examine whether the application of 3D virtual worlds in education is positive.
Trapped fermionic clouds distorted from the trap shape due to many-body effects
Creators: name: Haque, Masudul
name: Stoof, H. T. C.
Publisher: name: arXiv
Year: 2007
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Superconductivity (cond-mat.supr-con)
subject: FOS: Physical sciences

description: We present a general approach for calculating densities and other local quantities of trapped Fermi gases, when the cloud shape is distorted with respect to the trap shape due to global energy considerations. Our approach provides a consistent way to explore physics beyond the local density approximation, if this is necessary due to the distortion. We illustrate this by analyzing in detail experimentally observed distortions in an imbalanced Fermi mixture in an elongated trap. In particular, we demonstrate in that case dramatic deviations from ellipsoidal cloud shapes arising from the competition between surface and bulk energies.
description: 4+ pages, 3 figures. Formalism for distorted trapped fermi systems + treatment of polarized fermion experiments. Version 2: slightly shortened, published version
title: Rezension: Fokus Panofsky
Creators: name: Schreiber, Klaus
Publisher: name: ZZF - Centre for Contemporary History: Visual History
Year: 2019

description: Der Literatur-, Kunst- und Frühneuzeithistoriker mit einem Schwerpunkt bei der Mittelalter- und Renaissanceforschung Dieter Wuttke (Jg. 1929), zuletzt von 1979 bis 1995 Inhaber des von ihm gegründeten Lehrstuhls für Deutsche Philologie des Mittelalters und der Frühen Neuzeit an der Universität Bamberg, ist den Lesern von IFB zuletzt mit der Rezension der dritten, ihm zum 80. Geburtstag gewidmeten Festschrift begegnet. Leser von IFB mit einem längeren Gedächtnis wissen freilich auch, dass er sich mit zentralen Figuren des Warburg-Kreises befasst hat, so insbesondere mit dem Gründer des Warburg-Instituts Aby M. Warburg (1866-1929), dessen Personalbibliographie er bearbeitet hat, sowie mit Erwin Panofsky (1892-1968), der nach Warburgs Tod zusammen mit Fritz Saxl eine der zentralen Figuren der Kulturwissenschaftlichen Bibliothek Warburg in Hamburg war.
Numerical simulation of QCD with u, d, s and c quarks in the twisted-mass Wilson formulation
Creators: name: Chiarappa, T.
name: Farchioni, F.
name: Jansen, K.
name: Montvay, I.
name: Scholz, E. E.
name: Scorzato, L.
name: Sudmann, T.
name: Urbach, C.
Publisher: name: arXiv
Year: 2006
Subjects: subject: High Energy Physics - Lattice (hep-lat)
subject: FOS: Physical sciences

description: A first study of numerical Monte Carlo simulations with two quark doublets, a mass-degenerate one and a mass-split one, interpreted as u, d, s and c quarks, is carried out in the framework of the twisted mass Wilson lattice formulation. Tuning the bare parameters of this theory is explored on 12^3x24 and 16^3x32 lattices at lattice spacings a=0.20fm and a=0.15fm, respectively.
description: 27 pages, 6 figures
Implementation of Two Layers Type Theory in Dedukti and Application to Cubical Type Theory
Creators: name: Barras, Bruno
name: Maestracci, Valentin
Publisher: name: arXiv
Year: 2021
Subjects: subject: Logic in Computer Science (cs.LO)
subject: FOS: Computer and information sciences

description: In this paper, we make a substantial step towards an encoding of Cubical Type Theory (CTT) in the Dedukti logical framework. Type-checking CTT expressions features a decision procedure in a de Morgan algebra that so far could not be expressed by the rewrite rules of Dedukti. As an alternative, 2 Layer Type Theories are variants of Martin-Löf Type Theory where all or part of the definitional equality can be represented in terms of a so-called external equality. We propose to split the encoding by giving an encoding of 2 Layer Type Theories (2LTT) in Dedukti, and a partial encoding of CTT in 2LTT.
description: In Proceedings LFMTP 2020, arXiv:2101.02835
Giant Gravitons in the Schrodinger holography
Creators: name: Georgiou, George
name: Zoakos, Dimitrios
Publisher: name: arXiv
Year: 2020
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: We construct and study new giant graviton configurations in the framework of the non-supersymmetric Schrodinger holography. We confirm in the original Schrodinger spacetime, the picture discovered previously in the pp-wave limit of the geometry, namely that it is the giant graviton that becomes the energetically favored stable configuration compared to the point graviton one. Furthermore, there is a critical value of the deformation above which the point graviton disappears from the spectrum. The former fact leads also to the possibility of tunnelling from the point graviton to the giant graviton configuration. We calculate, explicitly, the instanton solution and its corresponding action which gives a measure of the tunnelling probability. Finally, we evaluate holographically the three-point correlation function of two giant gravitons and one dilaton mode as a function of the Schrodinger invariant.
description: 20 pages, 8 figures
Η Εγελιανή ανάγνωση της Θρησκείας:
Creators: name: Κουκούνας, Ιωάννης Παύλου
Publisher: name: Aristotle University of Thessaloniki
Year: 2012
Subjects: Είναι
Ουσία
Εννοια
Being
Substance
Thought

description: Με την ακόλουθη εργασία επιχειρείται να αναδειχθεί ο τρόπος με τον οποίο ο Χέγκελ κατανοεί τη θρηκεία, μέσα από τις επιμέρους εκφάνσεις του Ιουδαϊσμού, της Eλληνικής θρησκείας και του Χριστιανισμού, σε σχέση με τις λογικές κατηγορίες του Είναι, της Ουσίας και της Έννοιας. Στον Χέγκελ, η θρησκεία σχετίζεται με τη γνώση. Μέσα από τις διάφορες εκφάνσεις της θρησκείας η συνείδηση γίνεται αυτοσυνείδηση. Ο Ιουδαϊσμός είναι η θρησκεία εκείνη, στην οποία κυριαρχεί η παράσταση του Είναι, ενώ στην ελληνική θρησκεία η ουσία. O Χριστιανισμός συνιστά την απόλυτη θρησκεία, στην οποία το πνεύμα γνωρίζει τον εαυτό του και καθίσταται αυτοσυνείδηση, ως ελευθερία και αλήθεια.
description: With the following work is enterprised to be seen Hegel’s mode of understanding religion, throu the partial expressions of the Judaism, Greek religion and Christianism, in relation to the logical categories of the Being, Substance and Thought. On Hegel the religion is related to the knowledge. Throu the many expressions of the religion the conciousness becomes self-conciousness. The Judaism is the religion, in wich predominates the presentation of the Being, while in the Greek religion the Substance. The Christianism is the absolute religion, in wich the spirit knows its-self and becomes self-conciousness as freedom and truth.
Localization Theory in Zero Dimension and the Structure of Diffusion Poles
Creators: name: Suslov, I. M.
Publisher: name: arXiv
Year: 2008
Subjects: subject: Other Condensed Matter (cond-mat.other)
subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: High Energy Physics - Phenomenology (hep-ph)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: The 1/[-iω+ D(ω, q)q^2] diffusion pole in the localized phase transfers to the 1/ωBerezinskii-Gorkov singularity, which can be analyzed by the instanton method (M V. Sadovskii, 1982; J. L. Cardy, 1978). Straightforward use of this approach leads to contradictions, which do not disappear even if the problem is extremely simplied by taking zero-dimensional limit. On the contrary, they are extremely sharpened in this case and become paradoxes. The main paradox is specified by the following statements: (i) the 1/ωsingularity is determined by high orders of perturbation theory, (ii) the high-order behaviors for two quantities Φ^{RA} and U^{RA} are the same, and (iii) Φ^{RA} has the 1/ωsingularity, whereas U^{RA} does not have it. Solution to the paradox indicates that the instanton method makes it possible to obtain only the 1/(ω+ iγ) singularity, where the parameter γremains indefinite and must be determined from additional conditions. This conceptually confirms the necessity of the self-consistent treatment for the diffusion coefficient that is used in the Vollhardt-Wolfle type theories.
description: PDF, 11pages
Resonant four-photon scattering of collinear laser pulses in plasma
Creators: name: Malkin, V. M.
name: Fisch, N. J.
Publisher: name: arXiv
Year: 2020
Subjects: subject: Plasma Physics (physics.plasm-ph)
subject: Pattern Formation and Solitons (nlin.PS)
subject: Fluid Dynamics (physics.flu-dyn)
subject: Optics (physics.optics)
subject: FOS: Physical sciences

description: Exact four-photon resonance of collinear planar laser pulses is known to be prohibited by the classical dispersion law of electromagnetic waves in plasma. We show here that the renormalization produced by an arbitrarily small relativistic electron nonlinearity removes this prohibition. The laser frequency shifts in collinear resonant four-photon scattering increase with laser intensities. For laser pulses of frequencies much greater than the electron plasma frequency, the shifts can also be much greater than the plasma frequency and even nearly double the input laser frequency at still small relativistic electron nonlinearities. This may enable broad range tunable lasers of very high frequencies and powers. Since the four-photon scattering does not rely on the Langmuir wave, which is very sensitive to plasma homogeneity, such lasers would also be able to operate at much larger plasma inhomogeneities than lasers based on stimulated Raman scattering in plasma.
description: 6 pages, 3 figures
title: Μιμητικός αλγόριθμος για το ανοιχτό πρόβλημα δρομολόγησης οχημάτων
title: Memetic algorithm for the open vehicle routing problem
Creators: name: Βαλλιανατος Νικολαος
Publisher: name: Technical University of Crete
Year: 2024

description: Στόχος της εργασίας είναι η ανάπτυξη κώδικα Python που θα βελτιστοποιεί ανοικτά προβλήματα δρομολόγησης οχημάτων με την χρήση μιμητικού αλγορίθμου και αλγορίθμου τοπικής αναζήτησης 3opt.
Με δεδομένα τις συντεταγμένες μιας αποθήκης και διαφόρων κόμβων εξυπηρέτησης σε έναν χάρτη, την χωρητικότητα των οχημάτων, τον μέγιστο χρόνο διαδρομής των οχημάτων, τον χρόνο εξυπηρέτησης σε κάθε κόμβο και την ζήτηση κάθε κόμβου, σκοπός του κώδικα είναι η δρομολόγηση οχημάτων με την μικρότερη δυνατή διανυόμενη απόσταση για την εξυπηρέτηση της ζήτησης των κόμβων.
description: The aim of the thesis is to develop Python code that will optimize Open Vehicle Routing Problems using memetic and 3opt local search algorithm. Given the coordinates of a warehouse and various service nodes on a map, the capac the demand of each node, the purpose of the code is to route vehicles with the shortest possible travel distance to serve the demand of every node.
Wave condensation with weak disorder versus beam self-cleaning in multimode fibers
Creators: name: Garnier, J.
name: Fusaro, A.
name: Baudin, K.
name: Michel, C.
name: Krupa, K.
name: Millot, G.
name: Picozzi, A.
Publisher: name: arXiv
Year: 2020
Subjects: subject: Optics (physics.optics)
subject: Pattern Formation and Solitons (nlin.PS)
subject: FOS: Physical sciences

description: Classical nonlinear random waves can exhibit a process of condensation. It originates in the singularity of the Rayleigh-Jeans equilibrium distribution and it is characterized by the macroscopic population of the fundamental mode of the system. Several recent experiments revealed a phenomenon of spatial beam cleaning of an optical field that propagates through a graded-index multimode optical fiber (MMF). Our aim in this article is to provide physical insight into the mechanism underlying optical beam self-cleaning through the analysis of wave condensation in the presence of structural disorder inherent to MMFs. We consider experiments of beam cleaning where long pulses are injected in the and populate many modes of a 10-20 m MMF, for which the dominant contribution of disorder originates from polarization random fluctuations (weak disorder). On the basis of the wave turbulence theory, we derive nonequilibrium kinetic equations describing the random waves in a regime where disorder dominates nonlinear effects. The theory reveals that the presence of a conservative weak disorder introduces an effective dissipation in the system, which is shown to inhibit wave condensation in the usual continuous wave turbulence approach. On the other hand, the experiments of beam cleaning are described by a discrete wave turbulence approach, where the effective dissipation induced by disorder modifies the regularization of wave resonances, which leads to an acceleration of condensation that can explain the effect of beam self-cleaning. The simulations are in quantitative agreement with the theory. The analysis also reveals that the effect of beam cleaning is characterized by a repolarization as a natural consequence of the condensation process. In addition, the discrete wave turbulence approach explains why optical beam self-cleaning has not been observed in step-index multimode fibers.
description: 11 figures
Jet Speeds in Wide Angle Tailed Radio Galaxies
Creators: name: Jetha, Nazirah N.
name: Hardcastle, Martin J.
name: Sakelliou, Irini
name: .
Publisher: name: arXiv
Year: 2006
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: We present a sample of 30 wide angle tailed radio galaxies (WATs) that we use to constrain the jet speeds in these sources. We measure the distribution of jet-sidedness ratios for the sample, and assuming that the jets are beamed, jet speeds in the range (0.3-0.7)c are obtained. Whilst the core prominence of the sample, which ought to be a reliable indicator of beaming, shows little correlation with the jet-sidedness, we argue that due to the peculiar nature of WATs core-prominence is unlikely to be a good indicator of beaming in these sources. We further show that if the jets are fast and light, then the galaxy speeds required to bend jets into C-shapes such as those seen in 0647+693 are reasonable for a galaxy in a merging or recently merged cluster.
description: 10 pages, 18 figures, accepted for publication in MNRAS
Colliding Branes in Heterotic M-theory
Creators: name: Lehners, Jean-Luc
name: McFadden, Paul
name: Turok, Neil
Publisher: name: arXiv
Year: 2006
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: Astrophysics (astro-ph)
subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: We study the collision of two flat, parallel end-of-the-world branes in heterotic M-theory. By insisting that there is no divergence in the Riemann curvature as the collision approaches, we are able to single out a unique solution possessing the local geometry of (2d compactified Milne)/Z_2 x R_3, times a finite-volume Calabi-Yau manifold in the vicinity of the collision. At a finite time before and after the collision, a second type of singularity appears momentarily on the negative-tension brane, representing its bouncing off a zero of the bulk warp factor. We find this singularity to be remarkably mild and easily regularised. The various different cosmological solutions to heterotic M-theory previously found by other authors are shown to merely represent different portions of a unique flat cosmological solution to heterotic M-theory.
description: 29 pp, 4 figs; Appendix B revised to include junction condition for scalar
Η "λατρεία" του Ηγεμόνα: θεοποίηση, ιδεολογία και πολιτική κατά τη βασιλεία των τεσσάρων πρώτων Πτολεμαίων
Creators: name: Κουτουπάς, Αθανάσιος Ευθυμίου
Publisher: name: Aristotle University of Thessaloniki
Year: 2012
Subjects: Πτολεμαίος
Λατρεία του Ηγεμόνα
Ελληνιστική εποχή
Θεοποίηση
Ιδεολογία και προπαγάνδα
Ptolemy
Ruler cult
Helenistic era
Deification
Ideology and propaganda

description: Σκοπός της διατριβής είναι η μελέτη του φαινομένου της «λατρείας» του ηγεμόνα στο Πτολεμαϊκό βασίλειο την περίοδο της βασιλείας των τεσσάρων πρώτων Πτολεμαίων. Εξετάζουμε τους τρόπους με τους οποίους οι Πτολεμαίοι βασιλείς προώθησαν τη λατρεία στο πρόσωπο του βασιλιά μέσα από συγκεκριμένες ενέργειες και πράξεις. Σημαντική διαπίστωση αποτελεί ο καθοριστικός ρόλος που έπαιξαν η πολιτική και η ιδεολογία, καθώς προσέφεραν το απαραίτητο υπόβαθρο πάνω στο οποίο στηρίχτηκαν αυτές οι ενέργειες. Στη συνέχεια μελετάμε πώς το διαθέσιμο αρχαιολογικό υλικό στηρίζει την ύπαρξη του υπό εξέταση φαινομένου. Ένα άλλο θέμα που θίγουμε είναι η συνεισφορά της λογοτεχνίας της εποχής, μέσα από τα έργα του Καλλίμαχου, του Θεόκριτου και του Απολλώνιου, στην προώθηση της λατρείας των Πτολεμαίων.
description: The aim of the present thesis is the study of the Ruler “cult” within the Ptolemaic kingdom during the reign of the first four Ptolemies. We examine how the Ptolemies promoted the cult of the king through specific acts. A very crucial detection is the role of politics and ideology as they formed the background needed for the accomplishment of those acts. Also we see how the available archaeological material supports our hypothesis. Another aspect that we study is the contribution of the literature of that period in the promotion of the cult of the Ptolemies as it appears in the works of Callimachus, Theocritus and Apollonius.
Towards Unifying Structures in Higher Spin Gauge Symmetry
Creators: name: Bengtsson, Anders K. H.
Publisher: name: arXiv
Year: 2008
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: This article is expository in nature, outlining some of the many still incompletely understood features of higher spin field theory. We are mainly considering higher spin gauge fields in their own right as free-standing theoretical constructs and not circumstances where they occur as part of another system. Considering the problem of introducing interactions among higher spin gauge fields, there has historically been two broad avenues of approach. One approach entails gauging a non-Abelian global symmetry algebra, in the process making it local. The other approach entails deforming an already local but Abelian gauge algebra, in the process making it non-Abelian. In cases where both avenues have been explored, such as for spin 1 and 2 gauge fields, the results agree (barring conceptual and technical issues) with Yang-Mills theory and Einstein gravity. In the case of an infinite tower of higher spin gauge fields, the first approach has been thoroughly developed and explored by M. Vasiliev, whereas the second approach, after having lain dormant for a long time, has received new attention by several authors lately. In the present paper we briefly review some aspects of the history of higher spin gauge fields as a backdrop to an attempt at comparing the gauging vs. deforming approaches. A common unifying structure of strongly homotopy Lie algebras underlying both approaches will be discussed. The modern deformation approach, using BRST-BV methods, will be described as far as it is developed at the present time. The first steps of a formulation in the categorical language of operads will be outlined. A few aspects of the subject that seems not to have been thoroughly investigated are pointed out.
description: This is a contribution to the Proc. of the Seventh International Conference ''Symmetry in Nonlinear Mathematical Physics'' (June 24-30, 2007, Kyiv, Ukraine), published in SIGMA (Symmetry, Integrability and Geometry: Methods and Applications) at http://www.emis.de/journals/SIGMA/
Dispersion anomalies induced by the low-energy plasmon in the cuprates
Creators: name: Markiewicz, R. S.
name: Bansil, A.
Publisher: name: arXiv
Year: 2007
Subjects: subject: Superconductivity (cond-mat.supr-con)
subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: We discuss the characteristic effects of the electron plasmon interaction resulting from the ~ 1 eV plasmon, which is a universal feature in the cuprates. Using the framework of a one-band tight binding model, we identify signatures of this low energy plasmon in the electronic structure of metallic overdoped Bi2212 as well as half-filled insulating SCOC. The electron-plasmon interaction is found to yield renormalizations near the Fermi energy in reasonable accord with experimental observations, and to produce dispersion anomalies at higher energies.
description: 5 eps figures, revtex
Exploring conformational energy landscape of glassy disaccharides by CPMAS 13C NMR and DFT/GIAO simulations. I. Methodological aspects
Creators: name: Lefort, Ronan
name: Bordat, Patrice
name: Cesaro, Attilio
name: Descamps, Marc
Publisher: name: arXiv
Year: 2006
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: The aim of this article is to assess the ability of chemical shift surfaces to provide structural information on conformational distributions of disaccharides in glassy solid state. The validity of the general method leading to a simulation of inhomogeneous 13C chemical shift distributions is discussed in detail. In particular, a proper consideration of extrema and saddle points of the chemical shift map correctly accounts for the observed discontinuities in the experimental CPMAS spectra. Provided that these basic requirements are met, DFT/GIAO chemical shift maps calculated on relaxed conformations lead to a very satisfactory description of the experimental lineshapes. On solid-state trehalose as a model of amorphous disaccharide, this simulation approach defines unambiguously the most populated sugar conformation in the glass, and can help in discriminating the validity of different models of intramolecular energy landscape. Application to other molecular systems with broad conformational populations is foreseen to produce a larger dependence of the calculated chemical shift distribution on the conformational map.
Penalizations of the Brownian motion by a functional of its local times
Creators: name: Najnudel, Joseph
Publisher: name: arXiv
Year: 2007
Subjects: subject: Probability (math.PR)
subject: FOS: Mathematics
subject: 60B10, 60J65 (60G17, 60G44, 60J25, 60J55)

description: In this article, we study the family of probability measures (indexed by a positive real number t), obtained by penalization of the Brownian motion by a given functional of its local times at time t. We prove that this family tends to a limit measure when t goes to infinity if the functional satisfies some conditions of domination, and we check these conditions in several particular cases.