cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Διερεύνηση τριβολογικής συμπεριφοράς επιφανειών με μακροτραχύτητα (μικροδομή) που λειτουργούν υπό συνθήκες ελαστοϋδροδυναμικής λίπανσης:
Creators: name: Σαχανάς, Χρήστος Ι.
Publisher: name: Aristotle University of Thessaloniki
Year: 2014
Subjects: Τριβολογία
Μακροτραχύτητα (μικροδομή)
Ελαστοϋδροδυναμική λίπανση
Μικτή τριβή
Tribology
Microstructure (LST)
Elastohydrodynamic lubrication
Mixed lubrication

description: Πειραματική διερεύνηση της επίδρασης της μακροτραχύτητας (μικροδομή) στην ικανότητα των επιφανειών να μεταβούν από την περιοχή της μικτής στην περιοχή της υγρής τριβής. Για το σκοπό αυτό χρησιμοποιήθηκε το δοκιμαστήριο δίσκων του Εργαστηρίου Στοιχείων Μηχανών και Μηχανολογικού Σχεδιασμού του Α.Π.Θ. και εφαρμόστηκαν τεχνικές μέτρησης ηλεκτρικής αντίστασης επαφής (ECR). Δοκιμάστηκαν διαφορετικές παραλλαγές μακροτραχύτητας και συγκρίθηκαν με επιφάνειες χωρίς μακροτραχύτητα, αξιοποιώντας μετρήσεις ηλεκτρικής τάσης προκειμένου να διαπιστωθεί αν οι δύο επιφάνειες διαχωρίζονται πλήρως από Ελαστοϋδροδυναμικό σφήνα ή αν συμβαίνουν συγκρούσεις κορυφών τραχυτήτων. Προτάθηκε και δοκιμάστηκε νέα μέθοδος για τον προσδιορισμό της μεταλλικής επιφάνειας επαφής (απευθείας επαφή μετάλλου με μέταλλο, χωρίς την παρουσία μονομοριακού στρώματος λιπαντικού ή στρώματος οξειδίων). Τα αποτελέσματα έδειξαν ότι, για τις συνθήκες υπό τις οποίες έγιναν τα πειράματα, η μακροτραχύτητα μπορεί να λειτουργήσει θετικά ως προς την ικανότητα των επιφανειών να μεταβούν από την περιοχή της μικτής στην περιοχή της υγρής τριβής. Το αποτέλεσμα εξαρτάται κατά πολύ από τις συνθήκες λειτουργίας και τα γεωμετρικά χαρακτηριστικά της μακροτραχύτητας.
description: Experimental investigation of the influence of surface microstructure (Laser Surface Texturing – LST) on the capability of the surfaces to transit from mixed film to full film lubrication regime, using a two-disc test rig and employing electric contact resistance (ECR) measurement techniques. Different versions of texturing were compared to un-textured surfaces, utilizing electrical potential measurements, in order to identify if the two surfaces are completely separated by EHD film or if there are asperities collisions. A new methodology for the determination of the metallic contact area (direct metal-to-metal contact without the presence of single-molecule lubricant film or oxides layer) was proposed and tested. Results showed that under the operating conditions tested, LST may enhance the capability of the surfaces to transit from mixed film to full film lubrication regime. The result depends strongly on the operating conditions and the geometrical characteristics of LST.
Renormalization of Lorentz violating theories
Creators: name: Anselmi, Damiano
name: Halat, Milenko
Publisher: name: arXiv
Year: 2007
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: We classify the unitary, renormalizable, Lorentz violating quantum field theories of interacting scalars and fermions, obtained improving the behavior of Feynman diagrams by means of higher space derivatives. Higher time derivatives are not generated by renormalization. Renormalizability is ensured by a "weighted power counting" criterion. The theories contain a dimensionful parameter, yet a set of models are classically invariant under a weighted scale transformation, which is anomalous at the quantum level. Formulas for the weighted trace anomaly are derived. The renormalization-group properties are studied.
description: 28 pages, 1 figure; v2: more references and applications, PRD version
Essential spectra of difference operators on $\sZ^n$-periodic graphs
Creators: name: Rabinovich, V. S.
name: Roch, S.
Publisher: name: arXiv
Year: 2007
Subjects: subject: Mathematical Physics (math-ph)
subject: Functional Analysis (math.FA)
subject: FOS: Physical sciences
subject: FOS: Mathematics
subject: 81Q10, 46N50, 47B36

description: Let $(\cX, ρ)$ be a discrete metric space. We suppose that the group $\sZ^n$ acts freely on $X$ and that the number of orbits of $X$ with respect to this action is finite. Then we call $X$ a $\sZ^n$-periodic discrete metric space. We examine the Fredholm property and essential spectra of band-dominated operators on $l^p(X)$ where $X$ is a $\sZ^n$-periodic discrete metric space. Our approach is based on the theory of band-dominated operators on $\sZ^n$ and their limit operators. In case $X$ is the set of vertices of a combinatorial graph, the graph structure defines a Schrödinger operator on $l^p(X)$ in a natural way. We illustrate our approach by determining the essential spectra of Schrödinger operators with slowly oscillating potential both on zig-zag and on hexagonal graphs, the latter being related to nano-structures.
Brownian excursion area, Wright's constants in graph enumeration, and other Brownian areas
Creators: name: Janson, Svante
Publisher: name: arXiv
Year: 2007
Subjects: subject: Probability (math.PR)
subject: FOS: Mathematics
subject: 60J65, (Primary) 05C30, 60G15 (Secondary)

description: This survey is a collection of various results and formulas by different authors on the areas (integrals) of five related processes, viz.\spacefactor =1000 Brownian motion, bridge, excursion, meander and double meander; for the Brownian motion and bridge, which take both positive and negative values, we consider both the integral of the absolute value and the integral of the positive (or negative) part. This gives us seven related positive random variables, for which we study, in particular, formulas for moments and Laplace transforms; we also give (in many cases) series representations and asymptotics for density functions and distribution functions. We further study Wright's constants arising in the asymptotic enumeration of connected graphs; these are known to be closely connected to the moments of the Brownian excursion area. The main purpose is to compare the results for these seven Brownian areas by stating the results in parallel forms; thus emphasizing both the similarities and the differences. A recurring theme is the Airy function which appears in slightly different ways in formulas for all seven random variables. We further want to give explicit relations between the many different similar notations and definitions that have been used by various authors. There are also some new results, mainly to fill in gaps left in the literature. Some short proofs are given, but most proofs are omitted and the reader is instead referred to the original sources.
description: Published at http://dx.doi.org/10.1214/07-PS104 in the Probability Surveys (http://www.i-journals.org/ps/) by the Institute of Mathematical Statistics (http://www.imstat.org)
Multiple-Description Lattice Vector Quantization
Creators: name: Ostergaard, Jan
Publisher: name: arXiv
Year: 2007
Subjects: subject: Information Theory (cs.IT)
subject: FOS: Computer and information sciences

description: In this thesis, we construct and analyze multiple-description codes based on lattice vector quantization.
description: Ph.D. Thesis, 250 pages. (Thesis advisors: R. Heusdens and J. Jensen. Promotor: R. Lagendijk)
Rayleigh waves in isotropic strongly elliptic thermoelastic materials with microtemperatures
Creators: name: Passarella, Francesca
name: Tibullo, Vincenzo
name: Viccione, Giacomo
Publisher: name: arXiv
Year: 2021
Subjects: subject: Analysis of PDEs (math.AP)
subject: Mathematical Physics (math-ph)
subject: FOS: Mathematics
subject: FOS: Physical sciences

description: This paper is concerned with the linear theory of thermoelasticity with microtemperatures, based on the entropy balance proposed by Green and Naghdi, which permits the transmission of heat as thermal waves of finite speed. We analyze the behavior of Rayleigh waves in an unbounded isotropic homogeneous strongly elliptic thermoelastic material with microtemperatures. The related solution of the Rayleigh surface wave problem is expressed as a linear combination of the elements of the bases of the kernels of appropriate matrices. The secular equation is established and afterwards an explicit form is written when some coupling constitutive coefficients vanish. Then, we solve numerically the secular equation by mean of a grafical metod and by taking arbitrary data for strongly elliptic thermoelastic material.
Coupled Painlevé VI systems in dimension four with affine Weyl group symmetry of type $D_6^{(1)}$, II
Creators: name: Sasano, Yusuke
Publisher: name: arXiv
Year: 2007
Subjects: subject: Algebraic Geometry (math.AG)
subject: FOS: Mathematics
subject: 34M55, 34M45, 58F05, 32S65

description: We give a reformulation of a six-parameter family of coupled Painlevé VI systems with affine Weyl group symmetry of type $D_6^{(1)}$ from the viewpoint of its symmetry and holomorphy properties.
description: 14 pages, 5 figures
Dark Gravitational Sectors on a Generalized Scalar-Tensor Vector Bundle Model and Cosmological Applications
Creators: name: Konitopoulos, Spyros
name: Saridakis, Emmanuel N.
name: Stavrinos, P. C.
name: Triantafyllopoulos, A.
Publisher: name: arXiv
Year: 2021
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: In this work we present the foundations of generalized scalar-tensor theories arising from vector bundle constructions, and we study the kinematic, dynamical and cosmological consequences. In particular, over a pseudo-Riemannian space-time base manifold, we define a fiber structure with two scalar fields. The resulting space is a 6-dimensional vector bundle endowed with a non-linear connection. We provide the form of the geodesics and the Raychaudhuri and general field equations, both in Palatini and metrical method. When applied at a cosmological framework, this novel geometrical structure induces extra terms in the modified Friedmann equations, leading to the appearance of an effective dark energy sector, as well as of an interaction of the dark mater sector with the metric. We show that we can obtain the standard thermal history of the universe, with the sequence of matter and dark-energy epochs, and furthermore the effective dark-energy equation-of-state parameter can lie in the quintessence or phantom regimes, or exhibit the phantom-divide crossing.
description: 17 pages, 2 figures, version to appear in Phys.Rev.D
Lyman-alpha radiative transfer during the Epoch of Reionization: contribution to 21-cm signal fluctuations
Creators: name: Semelin, B.
name: Combes, F.
name: Baek, S.
Publisher: name: arXiv
Year: 2007
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: During the epoch of reionization, Ly-alpha photons emitted by the first stars can couple the neutral hydrogen spin temperature to the kinetic gas temperature, providing the opportunity to observe the gas in emission or absorption in the 21-cm line. Given the bright foregrounds, it is of prime importance to determine precisely the fluctuations signature of the signal, to be able to extract it by its correlation power. LICORICE is a Monte-Carlo radiative transfer code, coupled to the dynamics via an adaptative Tree-SPH code. We present here the Ly-alpha part of the implementation, and validate it through three classical tests. Contrary to previous works, we do not assume that P_alpha, the number of scatterings of Ly-alpha photons per atom per second, is proportional to the Ly-alpha background flux, but take into account the scatterings in the Ly-alpha line wings. The latter have the effect to steepen the radial profile of P_alpha around each source, and re-inforce the contrast of the fluctuations. In the particular geometry of cosmic filaments of baryonic matter, Ly-alpha photons are scattered out of the filament, and the large scale structure of P_alpha is significantly anisotropic. This could have strong implications for the possible detection of the 21-cm signal.
description: 13 pages, 9 figures. To be published in A&A
Hydrodynamics of Immiscible Binary Fluids with Viscosity Contrast: A multiparticle collision dynamics approach
Creators: name: Tan, Zihan
name: Calandrini, Vania
name: Dhont, Jan K. G.
name: Nägele, Gerhard
name: Winkler, Roland G.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Soft Condensed Matter (cond-mat.soft)
subject: Biological Physics (physics.bio-ph)
subject: Fluid Dynamics (physics.flu-dyn)
subject: FOS: Physical sciences

description: We present a multiparticle collision dynamics (MPC) implementation of layered immiscible fluids $A$ and $B$ of different shear viscosities separated by planar interfaces. The simulated flow profile for imposed steady shear motion and the time-dependent shear stress functions are in excellent agreement with our continuum hydrodynamics results for the composite fluid. The wave-vector dependent transverse velocity auto-correlation functions (TVAF) in the bulk-fluid regions of the layers decay exponentially, and agree with those of single-phase isotropic MPC fluids. In addition, we determine the hydrodynamic mobilities of an embedded colloidal sphere moving steadily parallel or transverse to a fluid-fluid interface, as functions of the distance from the interface. The obtained mobilities are in good agreement with hydrodynamic force multipoles calculations, for a no-slip sphere moving under creeping flow conditions near a clean, ideally flat interface. The proposed MPC fluid-layer model can be straightforwardly implemented, and it is computationally very efficient. Yet, owing to the spatial discretization inherent to the MPC method, the model can not reproduce all hydrodynamic features of an ideally flat interface between immiscible fluids.
description: 14 pages, 6 figures
Ιωάννης Γεωμέτρης, ιαμβικά ποιήματα: κριτική έκδοση, μετάφραση και σχόλια
Creators: name: Τωμαδάκη, Μαρία Πρ.
Publisher: name: Aristotle University of Thessaloniki
Year: 2014
Subjects: Ιωάννης Γεωμέτρης
Βυζαντινή ποίηση
Βυζαντινά επιγράμματα
Κριτική έκδοση
John Geometres
Byzantine poetry
Byzantine epigrams
Critical edition

description: Στόχος της παρούσας διδακτορικής διατριβής είναι η κριτική έκδοση, η μετάφραση και ο σχολιασμός 236 ιαμβικών ποιημάτων του Ιωάννη Γεωμέτρη. Τα ποιήματα αυτά αναφέρονται τόσο σε θρησκευτικά όσο και κοσμικά θέματα. Για παράδειγμα, είναι αφιερωμένα στον Χριστό, τη Θεοτόκο, σε αγίους, εικόνες, λείψανα, αλλά και σε Βυζαντινούς αυτοκράτορες, αρχαίους συγγραφείς και φιλοσόφους. Ως προς τη λειτουργία τους, θα μπορούσαν στην πλειονότητά τους να θεωρηθούν εν δυνάμει επιγραφές ή βιβλιακά επιγράμματα, καθώς και εγκωμιαστικά ποιήματα. Η παρούσα έκδοση βασίστηκε στον κώδικα Paris. Suppl. gr. 352 και αποτελείται από τέσσερα μέρη. Το πρώτο μέρος περιλαμβάνει έξι εισαγωγικά κεφάλαια που αναφέρονται στα βιογραφικά στοιχεία του ποιητή, στη θεματολογία, τις μετρικές συνήθειες, τη χειρόγραφη παράδοση των ιαμβικών του ποιημάτων, καθώς και στις αρχές της παρούσας έκδοσης. Στο δεύτερο μέρος περιλαμβάνεται η κριτική έκδοση των κειμένων και η απόδοσή τους στη Νεοελληνική. Στη συνέχεια ακολουθεί ο σχολιασμός των ποιημάτων, στο πλαίσιο του οποίου εξετάζονται ποικίλα φιλολογικά, γλωσσικά, προσωπογραφικά και ιστορικά ζητήματα αλλά και θέματα που αφορούν τη βυζαντινή τέχνη, ενώ το τελευταίο μέρος περιλαμβάνει τρία ευρετήρια (Index nominum, Index verborum notabilium και Index locorum).
description: The main purpose of my PhD dissertation was the critical edition, translation and annotation of 236 iambic poems of John Geometres. Τhese poems deal with both secular and Christian themes: for instance, there are poems devoted to Christ, Mary, saints, relics, icons and others on Byzantine emperors, ancient writers and philosophers. As for their function, the majority of them intended to be verse inscriptions, book epigrams and laudatory poems. My edition was based on Paris. Suppl. gr. 352 and includes four parts: The first one is an introduction with chapters on the poet, poetic themes, literary sources, meter, manuscripts and the editorial principles. The second involves the critical edition of the poems and their Modern Greek translation. The next one is a commentary on linguistic, philological, historical, prosopographical and artistic matters and the final section contains three indices (Index nominum, Index verborum notabilium and Index locorum).
MPEC 2024-T49 : 2024 SP9
Creators: name: Minor Planet Center Staff
Publisher: name: The Minor Planet Center
Year: 2024
Subjects: subject: Small Solar System bodies
valueUri: http://astrothesaurus.org/uat/1469
subject: 2024 SP9

description: The Minor Planet Electronic Circulars contain information on unusual minor planets, routine data on comets and natural satellites, and occasional editorial announcements.  They are published on behalf of Division F of the International Astronomical Union by the Minor Planet Center, Smithsonian Astrophysical Observatory, Cambridge, MA 02138, U.S.A.
Driven electronic bridge processes via defect states in $^{229}$Th-doped crystals
Creators: name: Nickerson, Brenden S.
name: Pimon, Martin
name: Bilous, Pavlo V.
name: Gugler, Johannes
name: Kazakov, Georgy A.
name: Sikorsky, Tomas
name: Beeks, Kjeld
name: Gruneis, Andreas
name: Schumm, Thorsten
name: Palffy, Adriana
Publisher: name: arXiv
Year: 2021
Subjects: subject: Atomic Physics (physics.atom-ph)
subject: FOS: Physical sciences

description: The electronic defect states resulting from doping $^{229}$Th in CaF$_2$ offer a unique opportunity to excite the nuclear isomeric state $^{229m}$Th at approximately 8 eV via electronic bridge mechanisms. We consider bridge schemes involving stimulated emission and absorption using an optical laser. The role of different multipole contributions, both for the emitted or absorbed photon and nuclear transition, to the total bridge rates are investigated theoretically. We show that the electric dipole component is dominant for the electronic bridge photon. In contradistinction, the electric quadrupole channel of the $^{229}$Th isomeric transition plays the dominant role for the bridge processes presented. The driven bridge rates are discussed in the context of background signals in the crystal environment and of implementation methods. We show that inverse electronic bridge processes quenching the isomeric state population can improve the performance of a solid-state nuclear clock based on $^{229m}$Th.
Warp Consistency for Unsupervised Learning of Dense Correspondences
Creators: name: Truong, Prune
name: Danelljan, Martin
name: Yu, Fisher
name: Van Gool, Luc
Publisher: name: arXiv
Year: 2021
Subjects: subject: Computer Vision and Pattern Recognition (cs.CV)
subject: FOS: Computer and information sciences

description: The key challenge in learning dense correspondences lies in the lack of ground-truth matches for real image pairs. While photometric consistency losses provide unsupervised alternatives, they struggle with large appearance changes, which are ubiquitous in geometric and semantic matching tasks. Moreover, methods relying on synthetic training pairs often suffer from poor generalisation to real data. We propose Warp Consistency, an unsupervised learning objective for dense correspondence regression. Our objective is effective even in settings with large appearance and view-point changes. Given a pair of real images, we first construct an image triplet by applying a randomly sampled warp to one of the original images. We derive and analyze all flow-consistency constraints arising between the triplet. From our observations and empirical results, we design a general unsupervised objective employing two of the derived constraints. We validate our warp consistency loss by training three recent dense correspondence networks for the geometric and semantic matching tasks. Our approach sets a new state-of-the-art on several challenging benchmarks, including MegaDepth, RobotCar and TSS. Code and models are at github.com/PruneTruong/DenseMatching.
description: Accepted to ICCV 2021 as an ORAL!
Quasi Equilibrium Grid Algorithm: geometric construction for model reduction
Creators: name: Chiavazzo, E.
name: Karlin, I. V.
Publisher: name: arXiv
Year: 2007
Subjects: subject: Statistical Mechanics (cond-mat.stat-mech)
subject: FOS: Physical sciences

description: The Method of Invariant Grid (MIG) is an iterative procedure for model reduction in chemical kinetics which is based on the notion of Slow Invariant Manifold (SIM) [1-4]. Important role, in that method, is played by the initial grid which, once refined, gives a description of the invariant manifold: the invariant grid. A convenient way to get a first approximation of the SIM is given by the Spectral Quasi Equilibrium Manifold (SQEM) [1-2]. In the present paper, a flexible numerical method to construct the discrete analog of a Quasi Equilibrium Manifold, in any dimension, is presented. That object is named Quasi Equilibrium Grid (QEG), while the procedure Quasi Equilibrium Grid Algorithm. Extensions of the QEM notion are also suggested. The QEG is a numerical tool which can be used to find a grid-based approximation for the locus of minima of a convex function under some linear constraints. The method is validated by construction of one and two-dimensional grids for model hydrogen oxidation reaction.
description: 31 pages, 13 figures
Strong lensing signatures of self-interacting dark matter in low-mass halos
Creators: name: Gilman, Daniel
name: Bovy, Jo
name: Treu, Tommaso
name: Nierenberg, Anna
name: Birrer, Simon
name: Benson, Andrew
name: Sameie, Omid
Publisher: name: arXiv
Year: 2021
Subjects: subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: FOS: Physical sciences

description: Core formation and runaway core collapse in models with self-interacting dark matter (SIDM) significantly alter the central density profiles of collapsed halos. Using a forward modeling inference framework with simulated datasets, we demonstrate that flux ratios in quadruple image strong gravitational lenses can detect the unique structural properties of SIDM halos, and statistically constrain the amplitude and velocity dependence of the interaction cross section in halos with masses between $10^6 - 10^{10} M_{\odot}$. Measurements on these scales probe self-interactions at velocities below $30 \ \rm{km} \ \rm{s^{-1}}$, a relatively unexplored regime of parameter space, complimenting constraints at higher velocities from galaxies and clusters. We cast constraints on the amplitude and velocity dependence of the interaction cross section in terms of $σ_{20}$, the cross section amplitude at $20 \ \rm{km} \ \rm{s^{-1}}$. With 50 lenses, a sample size available in the near future, and flux ratios measured from spatially compact mid-IR emission around the background quasar, we forecast $σ_{20} < 11-23 \ \rm{cm^2} \rm{g^{-1}}$ at $95 \%$ CI, depending on the amplitude of the subhalo mass function, and assuming cold dark matter (CDM). Alternatively, if $σ_{20} = 19.2 \ \rm{cm^2}\rm{g^{-1}}$ we can rule out CDM with a likelihood ratio of 20:1, assuming an amplitude of the subhalo mass function that results from doubly-efficient tidal disruption in the Milky Way relative to massive elliptical galaxies. These results demonstrate that strong lensing of compact, unresolved sources can constrain SIDM structure on sub-galactic scales across cosmological distances, and the evolution of SIDM density profiles over several Gyr of cosmic time.
description: matches version accepted to MNRAS
Quantum vortex tunneling in $YBa_2Cu_3O_{7-δ}$ thin films
Creators: name: Koren, G.
name: Mor, Y.
name: Auerbach, A.
name: Polturak, E.
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: Cuprate films offer a unique opportunity to observe vortex tunneling effects, due to their unusually low superfluid density and short coherence length. Here, we measure the magnetoresistance (\textit{MR}) due to vortex motion of a long meander line of a superconducting film made of underdoped $YBa_2Cu_3O_{7-δ}$. At low temperatures (\textit{T}), the \textit{MR} shows a significant deviation from Arrhenius activation. The data is consistent with two dimensional Variable Range Hopping (VRH) of single vortices, i.e. $MR\propto exp[-(T_0/T)^{1/3}]$. The VRH temperature scale $T_0$ depends on the vortex tunneling rates between pinning sites. We discuss its magnitude with respect to estimated parameters of the meander thin film.
description: 5 figures
Contact force measurements and local anisotropy in ellipses and disks
Creators: name: Wang, Yinqiao
name: Shang, Jin
name: Wang, Yujie
name: Zhang, Jie
Publisher: name: arXiv
Year: 2021
Subjects: subject: Soft Condensed Matter (cond-mat.soft)
subject: Disordered Systems and Neural Networks (cond-mat.dis-nn)
subject: Statistical Mechanics (cond-mat.stat-mech)
subject: FOS: Physical sciences

description: Experimental measurements of contact forces are limited to spheres and disks in three and two dimensions, making the evaluation of the shape effect and universality of force distributions and the comparison between experiments and theories extremely difficult. Here we present precise measurements of vector contact forces in photoelastic ellipses and disks subject to isotropic compression and pure shear. We find the local, instead of the global, stress ratio, control the width of the force distributions for forces larger than the mean, regardless of the particle shape and preparation protocols. By taking advantage of the anisotropic particle shape, we can determine the anisotropic growth of contacts in ellipses subject to isotropic compression, revealing the role of non-affine particle motions in homogenizing force distributions. Our results uncover the role of local anisotropy in the statistical framework of granular materials and open a new regime of exploring the role of particle shape on the mechanical and dynamical properties of granular materials in depth.
description: 18 pages, 4 figures
Measurement of critical current flow and connectivity in systems of joined square superconducting plates
Creators: name: Colauto, F.
name: Carmo, D.
name: de Andrade, A. M. H.
name: Oliveira, A. A. M.
name: Ortiz, W. A.
name: Galperin, Y. M.
name: Johansen, T. H.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Superconductivity (cond-mat.supr-con)
subject: FOS: Physical sciences

description: A method to measure the electrical connectivity between square superconducting plates joined by weak link interfaces is presented. It is based on observation of lines where the flow of critical current abruptly changes direction due to the presence of weak links, and the confinement created by the shape of the sample. The method is demonstrated using magneto-optical imaging (MOI) of systems consisting of up to 2 X 2 plates joined to form a larger square. Common features are found in the current flow patterns, which allow to measure the electrical connectivity between the plates by observing an angle between pairs of lines indicating where the current abruptly changes flow direction, so-called discontinuity, or d-lines. The samples used in this study are Nb films with weak links created by focused ion beam machining.
Drastic change in inelastic scattering depending on the development of dineutron correlation in $^{10}$Be
Creators: name: Furumoto, T.
name: Suhara, T.
name: Itagaki, N.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Nuclear Theory (nucl-th)
subject: Nuclear Experiment (nucl-ex)
subject: FOS: Physical sciences

description: We investigated the development and breaking of the dineutron correlation in $^{10}$Be by analyzing the elastic and inelastic scatterings with a framework combing the microscopic structure and reaction models. For studying the structure, the $^{10}$Be nucleus was constructed under the assumption of a four-body ($α+ α+ n + n$) cluster model. In this work, we focused on the change in the inner structure for the 0$_1^+$, 2$_1^+$, and 2$_2^+$ states when the strength of the spin-orbit interaction is varied. The inner structure, including various physical quantities such as energy, radius, and transition strength, is drastically influenced by the strength of the spin-orbit interaction. In particular, the development and breaking of the dineutron correlation is governed by the spin-orbit strength. The differences in the inner structure can be manifested by applying the obtained wave functions to elastic and inelastic scatterings with a proton target at $E/A =$ 59.4 and 200 MeV. Although the 0$_1^+$ and 2$_1^+$ states are significantly influenced by the spin-orbit strength of the nuclear structure calculation, the elastic and inelastic cross sections are not much affected. On the other hand, the inelastic cross section of the 2$_2^+$ state depends greatly on the spin-orbit strength of the structure calculation. Thus, we discovered a way to measure the degree of the development of dineutron cluster structure based on its sensitivity to the inelastic cross section of the 2$_2^+$ state of $^{10}$Be.
description: 22 pages, 7 figures, accepted for publication in Physical Review C
Can confidential research be reproducible: Consent, ethics, prison interviews and the Open Research agenda
Creators: name: Jarman, Ben
Publisher: name: Apollo - University of Cambridge Repository
Year: 2021
Subjects: open data
qualitative research
interview research
prison research
research ethics
open research

description: A presentation given at the ESRC DTP conference on 29th January 2021, reflecting on the Open Research agenda and some ethical questions it raises in relation to interviews conducted in prison.
The effect of rigid electron rotation on the Grad-Shafranov equilibria of a class of FRC devices
Creators: name: Swanson, C. P. S.
name: Cohen, S. A.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Plasma Physics (physics.plasm-ph)
subject: FOS: Physical sciences

description: Rigid electron rotation of a fully penetrated Rotamak-FRC produces a pressure flux function that is more peaked than the Solov'ev flux function. This paper explores the implications of this peaked pressure flux function, including the isothermal case, which appear when the temperature profile is broader than the density profile, creating both benefits and challenges to a Rotamak-FRC based fusion reactor. In this regime, the density distribution becomes very peaked, enhancing the fusion power. The separatrix has a tendency to become oblate, which can be mitigated by flux conserving current loops. Plasma extends outside the separatrix, notably in the open field line region. This model does not apply to very kinetic FRCs or FRCs in which there are significant ion flows, but it may have some applicability to their outer layers.
Matrices of infinite dimensions and their applications
Creators: name: Matysiak, Lukasz
name: Przewozniak, Weronika
name: Rulinska, Natalia
Publisher: name: arXiv
Year: 2021
Subjects: subject: General Mathematics (math.GM)
subject: FOS: Mathematics
subject: 15A83, 15A15

description: Matrices are very popular and widely used in mathematics and other fields of science. Every mathematician has known the properties of finite-sized matrices since the time of study. In this paper, we consider the basic theory of infnite matrices. So far, there have been references and few results in certain scientific fields, but they have not been thoroughly researched. This paper presents a complete possible and ordered theory of infinite matrices.
description: 7 pages, accepted in ITALIAN JOURNAL OF PURE AND APPLIED MATHEMATICS, 2021
Lightest scalar in the SU_L(2)*SU_R(2) linear σmodel
Creators: name: Achasov, N. N.
name: Shestakov, G. N.
Publisher: name: arXiv
Year: 2007
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: High Energy Physics - Experiment (hep-ex)
subject: Nuclear Theory (nucl-th)
subject: FOS: Physical sciences

description: We consider the lightest scalar meson in the frame of the $SU_L(2)\times SU_R(2)$ linear $σ$ model, keeping in mind that this model could be the low energy realization of the two-flavour QCD. We show that the $σ$ field is described by its four-quark component at least in the $σ$ resonance energy (virtuality) region and the $σ\toγγ$ decay is the four quark transition. We emphasize that residues of the $σ$ pole in the $ππ\toππ$ and $γγ\toππ$ amplitudes do not give an idea about the $σ$ meson nature, and the progress in studying the $σ$ meson production mechanisms in different processes could essentially further us in understanding its nature.
description: 10 pages, 3 figures, English improved, PACS numbers changed, two Refs. added, E-mail addresses removed and Ref. [1] shortened for the overrun of the article length allowable in Phys. Rev. Lett
Spectral analysis of boundary layers in Rayleigh-Benard convection
Creators: name: Verdoold, Jos
name: van Reeuwijk, Maarten
name: Tummers, Mark J.
name: Jonker, Harm J. J.
name: Hanjalić, Kemo
Publisher: name: arXiv
Year: 2007
Subjects: subject: Fluid Dynamics (physics.flu-dyn)
subject: FOS: Physical sciences

description: A combined experimental and numerical study of the boundary layer in a 4:1 aspect-ratio Rayleigh-Bénard cell over a four-decade range of Rayleigh numbers has been undertaken aimed at gaining a better insight into the character of the boundary layers. The experiments involved the simultaneous Laser Doppler Anemometry (LDA) measurements of fluid velocity at two locations, i.e. in the boundary layer and far away from it in the bulk, for Rayleigh numbers varying between $1.6 \times 10^7$ and $2.4 \times 10^9$. In parallel, direct numerical simulations (DNS) have been performed for the same configuration for Rayleigh numbers between $7.0 \times 10^4$ and $7.7 \times 10^7$. The temperature and velocity probability density functions and the power spectra of the horizontal velocity fluctuations measured in the boundary layer and in the bulk flow are found to be practically identical. Except for the smallest Rayleigh numbers, the spectra in the boundary layer and in the bulk central region are continuous and have a wide range of active scales. This indicates that both the bulk and the boundary layers are turbulent in the $\textrm{Ra}$ number range considered. However, molecular effects can still be observed and the boundary layer does not behave like a classical shear-driven turbulent boundary layer.
description: 10 pages, 6 figures, Accepted for publication in Phys. Rev. E
Geometric gradient-flow dynamics with singular solutions
Creators: name: Holm, Darryl D.
name: Putkaradze, Vakhtang
name: Tronci, Cesare
Publisher: name: arXiv
Year: 2007
Subjects: subject: Adaptation and Self-Organizing Systems (nlin.AO)
subject: Pattern Formation and Solitons (nlin.PS)
subject: FOS: Physical sciences

description: The gradient-flow dynamics of an arbitrary geometric quantity is derived using a generalization of Darcy's Law. We consider flows in both Lagrangian and Eulerian formulations. The Lagrangian formulation includes a dissipative modification of fluid mechanics. Eulerian equations for self-organization of scalars, 1-forms and 2-forms are shown to reduce to nonlocal characteristic equations. We identify singular solutions of these equations corresponding to collapsed (clumped) states and discuss their evolution.
description: 28 pages, 1 figure, to appear on Physica D
Powieść o Pliniuszu Młodszym
Creators: name: Szarmach, Marian
Year: 2018

description: Rocznik wydawany przez Komitet Nauk o Kulturze Antycznej Polskiej
 Akademii Nauk poświęcony kulturze świata starożytnego. Ukazuje się od
 1946 roku.

 "Meander" znajduje się na liście ERIH "Classical Studies" (kategoria
 NAT) i w części C wykazu czasopism MNiSW (10 pkt.).
A Framework for Design Thinking Outside the Design Profession:An Analysis of Design Thinking Implementations
Creators: name: Kallaya Tantiyaswasdikul
Publisher: name: Thammasat University
Year: 2019
Subjects: Design Thinking
Co-Creation
Systemic Thinking
Abductive Reasoning
Iteration
Collaborative Working

description: Journal of Architectural/Planning Research and Studies, 16, 1, 45-68
Connective memory and heritage on social media [Book proposal]
Creators: name: Dallas, Costis
name: Kelpšienė, Ingrida
name: Laužikas, Rimvydas
Publisher: name: Zenodo
Year: 2023

description: Based on a national case study involving systematic, multifocal analysis of a corpus of ca. 30,000 Facebook conversations and Instagram posts and over 60 interviews with mnemonic actors, the proposed volume demonstrates how the circulation of stories, symbols and metaphors, and the distribution of semiotic agency within a nexus involving heritage and the past, institutions and grassroots communities, and conversations on social media, act as powerful mechanisms for the construction of contemporary identities and attitudes towards the past, the present, and the future. It is based on research conducted as part of “Connective digital memory in borderlands: a mixed-methods study of cultural identity, heritage communication and digital curation on social networks”. The Connective project is funded by the European Social Fund under grant agreement 09.3.3-LMT-K-712-17-0027 with the Research Council of Lithuania (LMTLT). The proposal was submitted to an international academic publisher in November 2023 and is awaiting peer review. This document presents parts of the proposal suitable for public dissemination.
คุณลักษณะการเรียนรู้แบบนำตนเองของนักศึกษาปริญญาตรี คณะศิลปศึกษาสถาบันบัณฑิตพัฒนศิลป์
Creators: name: จริยา ตะลังวิทย์
Publisher: name: Walailak University
Year: 2019
Subjects: การเรียนรู้แบบนำตนเอง

description: วารสารนวัตกรรมการเรียนรู้ มหาวิทยาลัยวลัยลักษณ์, 5, 1, 1-19
Effect of flux-dependent Friedel oscillations upon the effective transmission of an interacting nano-system
Creators: name: Freyn, Axel
name: Pichard, Jean-Louis
Publisher: name: arXiv
Year: 2007
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: We consider a nano-system connected to measurement probes via non interacting leads. When the electrons interact inside the nano-system, the coefficient |ts(E_F)|^2 describing its effective transmission at the Fermi energy E_F ceases to be local. This effect of electron-electron interactions upon |ts(E_F)|^2 is studied using a one dimensional model of spinless fermions and the Hartree-Fock approximation. The non locality of |ts(E_F)|^2 is due to the coupling between the Hartree and Fock corrections inside the nano-system and the scatterers outside the nano-system via long range Friedel oscillations. Using this phenomenon, one can vary |ts(E_F)|^2 by an Aharonov-Bohm flux threading a ring which is attached to one lead at a distance Lc from the nano-system. For small distances Lc, the variation of the quantum conductance induced by this non local effect can exceed 0.1 (e^2/h).
Bosonic $η$-deformed $AdS_4\times\mathbb{CP}^3$ Background
Creators: name: Rado, Laura
name: Rivelles, Victor O.
name: Sánchez, Renato
Publisher: name: arXiv
Year: 2021
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: We build the bosonic $η$-deformed $AdS_4\times\mathbb{CP}^3$ background generated by an $r$-matrix that satisfies the modified classical Yang-Baxter equation. In a special limit we find that it is the gravity dual of the noncommutative ABJM theory.
description: 13 pages, added comments in sections 1, 4 and 5; added references [25,26,27], deleted comments on $AdS_4\times S^7$
Gate-induced insulating state in bilayer graphene devices
Creators: name: Oostinga, Jeroen B.
name: Heersche, Hubert B.
name: Liu, Xinglan
name: Morpurgo, Alberto F.
name: Vandersypen, Lieven M. K.
Publisher: name: arXiv
Year: 2007
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: The potential of graphene-based materials consisting of one or a few layers of graphite for integrated electronics originates from the large room-temperature carrier mobility in these systems (approx. 10,000 cm2/Vs). However, the realization of electronic devices such as field-effect transistors will require controlling and even switching off the electrical conductivity by means of gate electrodes, which is made difficult by the absence of a bandgap in the intrinsic material. Here, we demonstrate the controlled induction of an insulating state - with large suppression of the conductivity - in bilayer graphene, by using a double-gate device configuration that allows an electric field to be applied perpendicular to the plane. The dependence of the resistance on temperature and electric field, and the absence of any effect in a single-layer device, strongly suggest that the gate-induced insulating state originates from the recently predicted opening of a bandgap between valence and conduction bands.
description: 17 pages, 5 figures
Bhattacharyya parameter of monomials codes for the Binary Erasure Channel: from pointwise to average reliability
Creators: name: Dragoi, Vlad-Florin
name: Cristescu, Gabriela
Publisher: name: arXiv
Year: 2021
Subjects: subject: Information Theory (cs.IT)
subject: Discrete Mathematics (cs.DM)
subject: FOS: Computer and information sciences

description: Monomial codes were recently equipped with partial order relations, fact that allowed researchers to discover structural properties and efficient algorithm for constructing polar codes. Here, we refine the existing order relations in the particular case of Binary Erasure Channel. The new order relation takes us closer to the ultimate order relation induced by the pointwise evaluation of the Bhattacharyya parameter of the synthetic channels. The best we can hope for is still a partial order relation. To overcome this issue we appeal to related technique from network theory. Reliability network theory was recently used in the context of polar coding and more generally in connection with decreasing monomial codes. In this article, we investigate how the concept of average reliability is applied for polar codes designed for the binary erasure channel. Instead of minimizing the error probability of the synthetic channels, for a particular value of the erasure parameter p, our codes minimize the average error probability of the synthetic channels. By means of basic network theory results we determine a closed formula for the average reliability of a particular synthetic channel, that recently gain the attention of researchers.
description: 21 pages, 5 figures, 3 tables. Submitted for possible publication
On multivariate unimodal distributions
Creators: name: Dai, Tao
Publisher: name: University of British Columbia
Year: 2010

description: In this thesis, Kanter's representation of multivariate unimodal distributions is shown equivalent to the usual mixture of uniform distributions on symmetric, compact and convex sets. Kanter's idea is utilized in several contexts by viewing multivariate distributions as mixtures of uniform distributions on sets of various shapes. This provides a unifying viewpoint of what is in the literature and gives some important new classes of multivariate unimodal distributions. The closure properties of these new classes under convolution, marginality and weak convergence, etc. and their relationships with other notions of multivariate unimodality are discussed. Some interesting examples and their 2- or 3-dimensional pictures are presented.
Molecular Dynamics Study of a Thermal Expansion Coefficient: Ti Bulk with an Elastic Minimum Image Method
Creators: name: Hundur, Yakup
name: Hippler, Rainer
name: Guvenc, Ziya B.
Publisher: name: arXiv
Year: 2007
Subjects: subject: Computational Physics (physics.comp-ph)
subject: Atomic and Molecular Clusters (physics.atm-clus)
subject: FOS: Physical sciences

description: Linear thermal expansion coefficient (TEC) and specific heat of Ti bulk is investigated by means of molecular dynamics simulation. Elastic Minimum Image Convention of periodic boundary conditions is introduced to allow the bulk to adjust its size according to the new temporarily fixed temperature. The TEC and the specific heat of Ti are compared to the available theoretical and experimental data.
description: 4 pages, 3 figures
Determination of correlation coefficient between geoid-to-quasigeoid separation calculated by the satellite data in Sjöberg’s equation and GPS/Levelling method
Creators: name: Eshaghzadeh, Ata
name: Kalantari, Roghayeh Alsadat
name: Hekmat, Zohreh Moeini
Publisher: name: Commitee on Geodesy PAS
Year: 2018
Subjects: ICGEM
quasigeoid
geoid
Sjöberg’s equation
GPS/levelling

description: The Geodesy and Cartography is a semi-annually scientific journal
 publishing peer-reviewed articles with original solutions of
 theoretical, experimental or applicable problems in the field of
 geodesy, surveying engineering, cartography and GIS, cadastre and land
 management, photogrammetry, remote sensing and related disciplines.

 The Geodesy and Cartography is published under the umbrella of the
 Committee on Geodesy of the Polish Academy of Sciences (PAS).

  Printed version ISSN 2080-6736, On-line version ISSN
 2300-2581
description: In this paper, two techniques for calculating the geoid-to-quasigeoid
 separation are employed. One of them is GPS/Levelling customary method
 as a criterion where the geoid undulation and height anomaly are
 computed by subtracting the ellipsoid height attained via GPS from the
 orthometric height and normal height, respectively. Another approach is
 Sjöberg’s equation. We have used of the ICGEM website for definition of
 the variables of the Sjöberg’s equation, as the applied reference model
 is the EGM2008 global geopotential model and WGS84 reference ellipsoid.
 The investigations are performed over the stations of the GPS/Leveling
 network related to three selected areas in desert, mountain and flatland
 namely the Lout, Zagros and Khuzestan in Iran and afterward the
 correlation coefficient between the geoid-to-quasigeoid separation
 calculated using the satellite data in Sjöberg’s equation and
 GPS/Levelling method is estimated. The results indicate a straight
 correlation between the estimated separations from the two methods as
 its value for the Lout is 0.754, for the Zagros is 0.497 and for the
 Khuzestan is 0.659. consequently, using the satellite data in Sjöberg’s
 equation for the regions where there are not the GPS/Levelling and land
 gravity data, specially for the even areas, yield a satisfactory
 response of the geoidto-quasigeoid separation.