cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Ανάλυση Συναισθήματος Βασισμένη στη Μηχανική Μάθηση σε Δεδομένα από το Twitter
Creators: name: Μητσοπούλου, Ειρήνη Ευσταθίου
Publisher: name: Aristotle University of Thessaloniki
Year: 2020
Subjects: Ανάλυση Συναισθήματος
Επεξεργασία Φυσικής Γλώσσας
Μηχανική Μάθηση
Sentiment Analysis
Natural Language Processing
Μachine Learning

description: H παρούσα διπλωματική εργασία πραγματεύεται μερικές από τις τεχνικές μηχανικής μάθησης με επίβλεψη, οι οποίες μπορούν να χρησιμοποιηθούν για την κατανόηση και επεξεργασία της φυσικής γλώσσας ως προς το συναισθηματικό της ύφος. Τα δεδομένα τα οποία συλλέχθηκαν είναι δεδομένα κειμένου (tweets), τα οποία προέρχονται από το κοινωνικό δίκτυο Twitter, όπου αξιολογήθηκε η πολικότητά τους και κατηγοριοποιήθηκαν σε τρεις κλάσεις: θετική, αρνητική και ουδέτερη. Το στάδιο μετά τη συλλογή τους ήταν η προ-επεξεργασία και ειδικότερα η εκτέλεση ενός είδους καθαρισμού στα δεδομένα και εν συνεχεία ακολούθησε η εξαγωγή των χαρακτηριστικών που θα τροφοδοτήσουν τον κατηγοριοποιητή. Έξι διαφορετικοί κατηγοριοποιητές μηχανικής μάθησης όπως οι Μultinomial Naive Bayes, Support Vector Machines, K-Nearest Neighbors, Decision Trees, Random Forest και τέλος ο κατηγοριοποιητής Νευρωνικού Δικτύου Multilayer Perceptron επιλέχθηκαν να εφαρμοστούν πειραματικά. Διαφορετικές μετρικές απόδοσης χρησιμοποιήθηκαν για την αξιολόγηση της απόδοσης των κατηγοριοποιητών μηχανικής μάθησης. Αναλύοντας τα αποτελέσματα απόδοσης, ο στόχος αυτής της έρευνας ήταν ή εύρεση του ταξινομητή που αποδίδει την υψηλότερη ακρίβεια στην ανάλυση συναισθήματος στο σύνολο δεδομένων που συλλέχθηκε από τον Τwitter
description: Τhe present thesis deals with several supervised machine learning techniques that can be used in order to understand and process natural language in terms of its sentimental style. The collected data is text data (tweets) from Twitter, the polarity of which is evaluated and classified into three categories: positive, negative and neutral. Data collection was followed by pre-processing and in particular the performance of some sort of data cleaning. Subsequently, features were extracted from clean data to feed the classifier. Six machine learning classifiers were experimentally applied, such as Multinomial Naive Bayes, Support Vector Machines, K-Nearest Neighbors, Decision Trees, Random Forest and finally the Multilayer Perceptron Neural Network. Different performance evaluation parameters were used to evaluate the performance of the machine learning techniques. By analyzing the performance results, the aim of this research was to find the classifier that attributes the highest accuracy to sentiment analysis in the data set collected from Τwitter
Unusual Features of QCD Low-Energy Modes in IR Phase
Creators: name: Alexandru, Andrei
name: Horváth, Ivan
Publisher: name: arXiv
Year: 2021
Subjects: subject: High Energy Physics - Lattice (hep-lat)
subject: Disordered Systems and Neural Networks (cond-mat.dis-nn)
subject: High Energy Physics - Theory (hep-th)
subject: Nuclear Theory (nucl-th)
subject: FOS: Physical sciences

description: It was recently proposed that there is a phase in thermal QCD (IR phase) at temperatures well above the chiral crossover, featuring elements of scale invariance in the infrared (IR). Here we study the effective spatial dimensions, $d_{IR}$, of Dirac low-energy modes in this phase, in the context of pure-glue QCD. Our $d_{IR}$ is based on the scaling of mode support toward thermodynamic limit, and hence is an IR probe. Ordinary extended modes, such as those at high energy, have $d_{IR}=3$. We find $d_{IR}<3$ in the spectral range whose lower edge coincides with $λ_{IR}=0$, the singularity of spectral density defining the IR phase, and the upper edge with $λ_A$, the previously identified Anderson-like non-analyticity. Details near $λ_{IR}$ are unexpected in that only exact zero modes are $d_{IR}=3$, while a thin spectral layer near zero is $d_{IR}=2$, followed by an extended layer of $d_{IR}=1$ modes. With only integer values appearing, $d_{IR}$ may have topological origin. We find similar structure at $λ_A$, and associate its adjacent thin layer ($d_{IR} >\approx 2$) with Anderson-like criticality. Our analysis reveals the manner in which non-analyticities at $λ_{IR}$ and $λ_A$, originally identified in other quantities, appear in $d_{IR}(λ)$. This dimension structure may be important for understanding the near-perfect fluidity of the quark-gluon medium seen in accelerator experiments. The role of $λ_A$ in previously conjectured decoupling of IR component is explained.
description: 5 pages, 5 figures; v2: minor changes, published version
Struggles and Triumphs (Editorial)
Creators: name: Kirkness, Verna
Publisher: name: Canadian Journal of Native Education
Year: 2021

description: The theme of this issue of the journal is “Struggles and Triumphs.” It contains four articles, each of which addresses a different aspect of the many challenges that face First Nations educators. The first article, by Opal Charters-Voght, docu­ ments a workshop that was designed to help a community take more real and meaningful control over its education, and thus to achieve the real goals of parental responsibility and local control as set out in the 1973 policy of “Indian control of Indian education.” In addition, it tells us about the outcomes of the workshop one year later. ...
description: Canadian Journal of Native Education, Vol. 18 No. 2 (1991)
A Nozzle Analysis of Slow-Acceleration Solutions in One-Dimensional Models of Rotating Hot-Star Winds
Creators: name: Madura, Thomas I.
name: Owocki, Stanley P.
name: Feldmeier, Achim
Publisher: name: arXiv
Year: 2007
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: We analyze the steady 1D flow equations for a rotating stellar wind based on a ``nozzle'' analogy for terms that constrain the local mass flux. For low rotation, we find the nozzle minimum occurs near the stellar surface, allowing a transition to a standard, CAK-type steep-acceleration solution; but for rotations > 75% of the critical rate, this inner nozzle minimum exceeds the global minimum, implying near-surface supercritical solutions would have an overloaded mass loss rate. In steady, analytic models in which the acceleration is assumed to be monotonically positive, this leads the solution to switch to a slow acceleration mode. However, time-dependent simulations using a numerical hydrodynamics code show that, for rotation rates 75 - 85% of critical, the flow can develop abrupt "kink" transitions from a steep acceleration to a decelerating solution. For rotations above 85% of critical, the hydrodynamic simulations confirm the slow acceleration, with the lower flow speed implying densities 5 - 30 times higher than the polar (or a nonrotating) wind. Still, when gravity darkening and 2D flow effects are accounted for, it seems unlikely that rotationally modified equatorial wind outflows could account for the very large densities inferred for the equatorial regions around B[e] supergiants.
description: Accepted for publication in the Astrophysical Journal. 13 pages, 9 figures
Noncommutative Differential K-theory
Creators: name: Park, Byungdo
name: Parzygnat, Arthur J.
name: Redden, Corbett
name: Stoffel, Augusto
Publisher: name: arXiv
Year: 2021
Subjects: subject: K-Theory and Homology (math.KT)
subject: Differential Geometry (math.DG)
subject: FOS: Mathematics
subject: Primary 19L50, Secondary 19D55, 58B34, 58J28

description: We introduce a differential extension of algebraic K-theory of an algebra using Karoubi's Chern character. In doing so, we develop a necessary theory of secondary transgression forms as well as a differential refinement of the smooth Serre--Swan correspondence. Our construction subsumes the differential K-theory of a smooth manifold when the algebra is complex-valued smooth functions. Furthermore, our construction fits into a noncommutative differential cohomology hexagon diagram.
description: 65 pages
Diagramming the Complexities of Historical Processes: From Ontology-based Modeling to Diagrammatic Reasoning
Creators: name: Frank, Ingo
Publisher: name: Zenodo
Year: 2019
Subjects: Ontology-based Modeling
Applied Ontology
Visual Contextualization
Diagrammatic Reasoning
Historical Explanation

description: This paper presents ongoing foundational theoretical and practical work on the application of ontology-based modeling to represent and visualize the complexity of knowledge disseminated in historical narratives. In short, the new approach combines modeling informed by philosophical ontology and philosophy of history with semiotically founded visualization of historical processes in order to support historical understanding.
Probing the non-linear structure of general relativity with black hole binaries
Creators: name: Arun, K. G.
name: Iyer, B. R.
name: Qusailah, M. S. S.
name: Sathyaprakash, B. S.
Publisher: name: arXiv
Year: 2006
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: Observations of the inspiral of massive binary black holes (BBH) in the Laser Interferometer Space Antenna (LISA) and stellar mass binary black holes in the European Gravitational-Wave Observatory (EGO) offer an unique opportunity to test the non-linear structure of general relativity. For a binary composed of two non-spinning black holes, the non-linear general relativistic effects depend only on the masses of the constituents. In a recent letter, we explored the possibility of a test to determine all the post-Newtonian coefficients in the gravitational wave-phasing. However, mutual covariances dilute the effectiveness of such a test. In this paper, we propose a more powerful test in which the various post-Newtonian coefficients in the gravitational wave phasing are systematically measured by treating three of them as independent parameters and demanding their mutual consistency. LISA (EGO) will observe BBH inspirals with a signal-to-noise ratio of more than 1000 (100) and thereby test the self-consistency of each of the nine post-Newtonian coefficients that have so-far been computed, by measuring the lower order coefficients to a relative accuracy of $\sim 10^{-5}$ (respectively, $\sim 10^{-4}$) and the higher order coefficients to a relative accuracy in the range $10^{-4}$-0.1 (respectively, $10^{-3}$-1).
description: 5 pages, 4 figures. Revised version, accepted for publication in Phys. Rev D
Effect of ultrasonic irradiation power on sonochemical synthesis of gold nanoparticles
Creators: name: Fuentes-García, J. A.
name: Santoyo-Salzar, J.
name: Rangel-Cortes, E.
name: Goya, G. F.
name: Cardozo-Mata, V.
name: Pescador-Rojas, J. A.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Soft Condensed Matter (cond-mat.soft)
subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: In this work, optimized size distribution and optical properties in colloidal synthesis of gold nanoparticles (GNPs) were obtained using a proposed ultrasonic Tuerkevich-Frens method. The effect of three ultrasound (20 kHz) irradiation powers has been analyzed as size and shape control parameter. The GNPs colloidal solutions were obtained from chloroauric acid (HAuCl$_{4}$) and trisodium citrate ($\rm C_{6}H_{5}Na_{3}O_{7}\cdot 2H_{2}O$) under continuous irradiation for 1 hour without any heat or stirring. The surface plasmon resonance (SPR) was monitored in the UV-Vis spectra every 10 minutes to found the optimal time for localized SPR wavelength ($λ_{\rm LSPR}$) and the 210 sample procedure reduces the $λ_{\rm LSPR}$ localization to 20 minutes, while 150 and 60 samples show $λ_{\rm LSPR}$ in 60 minutes. The nucleation and growth of GNPs showed changes in shape and size distribution, which were associated with physical (cavitation, temperature) and chemical (radical generation, pH) conditions in the solution. The results showed quasispherical GNPs as pentakis dodecahedron ($λ_{\rm LSPR}$=560 nm), triakis icosahedron ($λ_{\rm LSPR}$=535 nm), and tetrakis hexahedron ($λ_{\rm LSPR}$= 525 nm) in a size range from 12-16 nm. US irradiation induced a disproportionation process, electrons of AuCl$_{2}^-$ rapidly exchanged through the gold surface. After AuCl$_{4}^-$ and Cl$^-$ are desorbed and a complex tetrachloroaurate is recycled for the two-electron reduction by citrate, aurophilic interaction between complexes AuCl$_{2}^-$, electrons exchange and gold seeds, the deposition of new gold atoms on the surface promoting the growth of GNPs. These mechanisms are enhanced by the cavitation effects and transmitted energy into the solution, showing that the plasmonic response from our nanoparticles can be tuned with this simple method and minimum intrumentation.
description: 8 pages, 4 figures, 1 scheme
Constructing the Cubic Interaction Vertex of Higher Spin Gauge Fields
Creators: name: Buchbinder, I. L.
name: Fotopoulos, A.
name: Petkou, A. C.
name: Tsulaia, M.
Publisher: name: arXiv
Year: 2006
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: We propose a method of construction of a cubic interaction in massless Higher Spin gauge theory both in flat and in AdS space-times of arbitrary dimensions. We consider a triplet formulation of the Higher Spin gauge theory and generalize the Higher Spin symmetry algebra of the free model to the corresponding algebra for the case of cubic interaction. The generators of this new algebra carry indexes which label the three Higher Spin fields involved into the cubic interaction. The method is based on the use of oscillator formalism and on the Becchi-Rouet-Stora-Tyutin (BRST) technique. We derive general conditions on the form of cubic interaction vertex and discuss the ambiguities of the vertex which result from field redefinitions. This method can in principle be applied for constructing the Higher Spin interaction vertex at any order. Our results are a first step towards the construction of a Lagrangian for interacting Higher Spin gauge fields that can be holographically studied.
description: Published Version; comments added in introduction; minor typos and references corrected
Solar Gamma Ray Constraints on Dark Matter Annihilation to Secluded Mediators
Creators: name: Bell, Nicole F.
name: Dent, James B.
name: Sanderson, Isaac W.
Publisher: name: arXiv
Year: 2021
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: We consider the indirect detection of dark matter that is captured in the Sun and subsequently annihilates to long-lived dark mediators. If these mediators escape the Sun before decaying, they can produce striking gamma ray signals, either via the decay of the mediators directly to photons, or via bremsstrahlung and hadronization of the mediator decay products. Using recent measurements from the HAWC Observatory, we determine model-independent limits on heavy dark matter that are orders of magnitude more powerful than direct detection experiments, for both spin-dependent and spin-independent scattering. We also consider a well-motivated model in which fermionic dark matter annihilates to dark photons. For such a realistic scenario, the strength of the solar gamma ray constraints are reduced, compared to the idealistic case, because the dark matter capture cross section and mediator lifetime are related. Nonetheless, solar gamma ray constraints enable us to exclude a previously unconstrained region of dark photon parameter space.
description: 12 pages, 5 figures; updated to match published version
Birational geometry and deformations of nilpotent orbits
Creators: name: Namikawa, Yoshinori
Publisher: name: arXiv
Year: 2006
Subjects: subject: Algebraic Geometry (math.AG)
subject: FOS: Mathematics
subject: 14Exx, 14Jxx, 17Bxx

description: This is a continuation of math.AG/0408274, where we have described the relative movable cone for a Springer resolution of the closure of a nilpotent orbit in a complex simple Lie algebra. But, in general, the movable cone does not coincide with the whole space of numerical classes of divisors on the Springer resolution. The purpose of this paper is, to describe the remainder. We shall first construct a deformation of the nilpotent orbit closure in a canonical manner according to Brieskorn and Slodowy, and next describe all its crepant simultaneous resolutions. This construction enables us to divide the whole space into a finite number of chambers. Moreover, by using this construction, one can generalize the main result of math.AG/0408274 to arbitrary Richardson orbits whose Springer maps have degree > 1. New Mukai flops, different from those of type A,D,E_6, will appear in the birational geometry for such orbits.
description: 33 pages, revised
Το σύστημα των “gulam” στην οθωμανική αυτοκρατορία
Creators: name: Τσελούδη, Αντιγόνη Δημητρίου
Publisher: name: Aristotle University of Thessaloniki
Year: 2020
Subjects: Γκουλάμ
Παιδομάζωμα/Πεντζίκ
Δούλοι της Πύλης
Gulam
Devşirme/Pencik
Kapıkulları/Kul

description: Σκοπός της παρούσας εργασίας είναι να περιγράψει τη δομή και τη λειτουργία του συστήματος των “gulam”, ενός από τους βασικούς θεσμούς πάνω στους οποίους στηρίχτηκε η οργάνωση και η λειτουργία της οθωμανικής αυτοκρατορίας. Αρχικά γίνεται λόγος για την προέλευση του θεσμού και την εφαρμογή του στις προ-οθωμανικές ισλαμικές δυναστείες, ιδιαίτερα σε αυτή των Σελτζούκων, που αποτέλεσε και το άμεσο πρότυπο των Οθωμανών και δίνονται κάποιες γενικές πληροφορίες για την πρώιμη οθωμανική διοικητική οργάνωση. Στη συνέχεια γίνεται περιγραφή της οργάνωσης του συστήματος των “gulam”, δίνονται πληροφορίες για την προέλευση των “gulam” μέσω της εφαρμογής των δύο πρακτικών του “pencik” και του “devşirme”, καθώς και για την εκπαίδευση που λάμβαναν οι νεαροί δούλοι και για τα καθήκοντα και τα αξιώματα που αναλάμβαναν εντός και εκτός του οθωμανικού παλατιού. Επιπλέον, εξετάζεται η νομική θέση των “gulam” και κατά πόσον η πρακτική του “devşirme” συμβάδιζε με τις προσταγές του μουσουλμανικού “Şeriat”. Τέλος, γίνεται μια προσπάθεια να εξηγηθούν οι αιτίες που οδήγησαν στην παρακμή και κατάρρευση του συστήματος των “gulam”
description: The aim of the present thesis was the study of the structure and inner functions of the “gulam” system, one of the foundations of the military and administrative organization of the ottoman empire. At first, I refer to the origins of the institution and to its apply to pro-ottoman Islamic dynasties, especially the Seljuks, which was Ottomans’ historic model and main influence and I present some information about the early ottoman administrative structure. After that I describe how the “gulam” system was organized, how the “gulam” were acquired through the practices of “pencik” and “devşirme” as well as the young slaves’ education, duties and offices they took both inside and outside of the ottoman palace. Furthermore, I examine the “gulams’” position from a legal point of view and the accordance of the practice of “devşirme” with the muslim “Şeriat” law. Finally, there is an attempt to present and explain the reason that led to the decline and collapse of the “gulam” system
The H.E.S.S. View of the Central 200 Parsecs
Creators: name: Hinton, Jim
Publisher: name: arXiv
Year: 2006
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: The inner few hundred parsecs of our galaxy provide a laboratory for the study of the production and propagation of energetic particles. Very-high-energy gamma-rays provide an effective probe of these processes and, especially when combined with data from other wave-bands, gamma-rays observations are a powerful diagnostic tool. Within this central region, data from the H.E.S.S. instrument have revealed three discrete sources of very-high-energy gamma-rays and diffuse emission correlated with the distribution of molecular material. Here I provide an overview of these recent results from H.E.S.S.
description: Proceedings of the Galactic Centre Workshop 2006
Public housing and lethal violence
Creators: name: Lesneskie, Eric G.
Publisher: name: No Publisher Supplied
Year: 2013

description: After the Second World War, the Department of Housing and Urban Development (HUD) provided funding to local housing authorities to build large scale public housing developments in many cities across the United States.  Unfortunately, most of those housing projects were beset with a host of problems as time progressed, including deteriorating building structures, concentrated poverty, racial segregation, and crime.  In perhaps no city is this story more heavily studied than in Chicago.  Chicago’s public housing tribulations are legendary and are well documented in the academic literature. Many of Chicago’s projects were large high-rise projects located in disadvantaged, isolated, and residentially distinct neighborhoods with strong gang, drug, and crime presence. However, relatively little research has examined the association between Chicago’s public housing and homicide. Specifically, it is uncertain as to whether the unique physical and social environments of public housing developments have an independent effect on lethal violence or whether the high rates of homicides occurring in public housing areas are influenced predominately by neighborhood conditions. Utilizing the Chicago Homicide Data set, this dissertation disentangles the effects of public housing on lethal violence. This study, first, estimated negative binominal regression models to determine the effect of the presence of public housing on tract level rates of homicide. The results of these analyses indicate that the presence of public housing is not a significant predictor of the rates of lethal violence and neighborhood conditions are driving the high rates of homicides occurring in public housing areas. Secondly, the nature of lethal violence occurring in public housing areas was determined by using negative binominal regression and bivariate analyses. Homicides, disaggregated by motive, do not occur at higher rates or disproportionately in Chicago’s tracts with public housing compared to tracts without. The findings from this dissertation indicate that public housing areas do not seem to be micro places that influence a specific type of violence and that neighborhood conditions are driving the high rates of homicide occurring in public housing areas rather than the unique physical and social environments of public housing developments.
Μηχανική μάθηση και δομές δεδομένων
Creators: name: Κωστόπουλος, Κωνσταντίνος Παναγιώτη
Publisher: name: Aristotle University of Thessaloniki
Year: 2020
Subjects: μηχανική μάθηση
δομές δεδομένων
δείκτης σημείου
machine learning
data structures
point index

description: Οι παραδοσιακές Δομές Δεδομένων μπορούν να ενισχυθούν, αν όχι να αντικατασταθούν, από Μοντέλα Μηχανικής Μάθησης. Η βασική λειτουργία τους, της ανάκτησης δεδομένων, μπορεί να αντιμετωπιστεί από τη σκοπιά της Μηχανικής Μάθησης ως ένα Μοντέλο που έχοντας "μάθει" την υποβόσκουσα κατανομής τους, μπορεί να "προβλέψει" τη θέση ανάκτησής τους. Επομένως, η πράξη της ανάκτησης μπορεί να γίνει, θεωρητικά τουλάχιστον, πολυπλοκότητας O(1) χρόνου. Προσπαθήσαμε να δοκιμάσουμε στην πράξη αυτή την ιδέα, όπως την έχουν παρουσιάσει οι Kraska et al στο "The Case For Learned Index Structures", υλοποιώντας τον Δείκτη Σημείου (Point Index). Παραθέτουμε τα αποτελέσματα αυτής της προσπάθειάς μας, μαζί με κάποιες διορθώσεις στον αλγόριθμό τους. Τέλος, παρουσιάζουμε τις σκέψεις μας για τη συνέχιση της έρευνας πάνω στο συγκεκριμένο αντικείμενο
description: The traditional Data Structures can be enforced, if not replaced, by Machine Learning Models. Their main function, of accessing data, can be faced, from the point of view of Machine Learning, as a Model, which having “learned” the underlying distribution of data, can “predict” their position. So, the operation of access, can be accomplished, theoretically at least, with time complexity of O(1). We tried to test this idea, as it has been introduced in “The Case For Learned Index Structures” by Kraska et al, implementing the Point Index. We display the results of our effort, along with some corrections to their algorithm. Finally, we present our thoughts about the future direction of the specific research field
Production of Topological Defects at the End of Inflation
Creators: name: Sakellariadou, Mairi
Publisher: name: arXiv
Year: 2007
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: Astrophysics (astro-ph)
subject: General Relativity and Quantum Cosmology (gr-qc)
subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: Cosmological inflation and topological defects have been considered for a long time, either in disagreement or in competition. On the one hand an inflationary era is required to solve the shortcomings of the hot big bang model, while on the other hand cosmic strings and string-like objects are predicted to be formed in the early universe. Thus, one has to find ways so that both can coexist. I discuss how to reconcile cosmological inflation with cosmic strings.
description: 33 pages, 12 figures. Based on an invited talk at "Inflation + 25", 22nd IAP Colloquim, Paris (June 2006). To be published in the Proceedings (Springer Lecture Notes, 2007). Some new references
Estimating the birth period of pulsars through GLAST/LAT observations of their wind nebulae
Creators: name: de Jager, O. C.
Publisher: name: arXiv
Year: 2008
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: In this paper we show that the high energy $γ$-ray flux in the GeV domain from mature pulsar wind nebulae (PWN) scales as the change in rotational kinetic energy $I(Ω_0^2-Ω^2)/2$ since birth, rather than the present day spindown power $IΩ\dotΩ$. This finding holds as long as the lifetime of inverse Compton emitting electrons exceeds the age of the system. For a typical $γ^{-2}$ electron spectrum, the predicted flux depends mostly on the pulsar birth period, conversion efficiency of spindown power to relativistic electrons and distance to the PWN, so that first order estimates of the birth period can be assessed from {\it GLAST/LAT} observations of PWN. For this purpose we derive an analytical expression. The associated (``uncooled'') photon spectral index in the GeV domain is expected to cluster around $\sim 1.5$, which is bounded at low energies by an intrinsic spectral break, and at higher energies by a second spectral break where the photon index steepens to $\sim 2$ due to radiation losses. Mature PWN are expected to have expanded to sizes larger than currently known PWN, resulting in relatively low magnetic energy densities and hence survival of GeV inverse Compton emitting electrons. Whereas such a PWN may be radio and X-ray quiet in synchrotron radiation, it may still be detectable as a {\it GLAST/LAT} source as a result of the relic electrons in the PWN.
description: 10 pages, no figures. To appear in Astrophysical Journal Letters
Δυαδικό φίλτρο Kalman ενισχυμένο με νευρωνικό δίκτυο
Creators: name: Παππά, Ελένη Βασίλη
Publisher: name: Aristotle University of Thessaloniki
Year: 2020
Subjects: Νευρωνικά δίκτυα
Φίλτρο Kalman
Παράτυπα σημεία
Neural Networks
Kalman Filter
Outliers

description: Στόχος της παρούσας εργασίας είναι να παρουσιάσει το Δυαδικό Φίλτρο Kalman και πως αυτό βελτιώνεται με την αξιοποίηση Νευρωνικού Δικτύου στην περίπτωση που τα δεδομένα περιέχουν παράτυπα σημεία. Αρχικά περιγράφονται οι εξελικτικοί αλγόριθμοι, μία κατηγορία μεταευρετικών αλγορίθμων, και αναλύεται η Στοχαστική Κλασματική Αναζήτηση (SFS). Στη συνέχεια παρουσιάζονται τα Νευρωνικά Δίκτυα. Αναλύεται ο τρόπος λειτουργίας τους, παρατίθεται η τεχνική εκπαίδευσης Ανάστροφης Μετάδοσης Λάθους, αποσαφηνίζονται τα Perceptron και τα Πολυεπίπεδα Perceptron (MLP), παρουσιάζονται θεωρητικά αποτελέσματα που δικαιολογούν την επιλογή Νευρωνικών δικτύων ως εκτιμητές και τέλος γίνεται αναφορά στο πώς οι εξελικτικοί αλγόριθμοι βελτιώνουν την εκπαίδευση των δικτύων παράλληλα με την παρουσίαση του MLP-SFS. Το τρίτο μέρος της εργασίας αφορά το Φίλτρο Kalman. Παρουσιάζεται το Δυαδικό Φίλτρο Kalman καθώς και το Φίλτρο Kalman που ενισχύεται με MLP δίκτυο προκειμένου να αξιοποιηθούν επιπλέον πληροφορίες που αφορούν τη φύση του προβλήματος. Τέλος, ορίζεται το πρόβλημα της αποτελεσματικής συνδεσιμότητας των ενεργών περιοχών του εγκεφάλου και εφαρμόζεται ένας υβριδικός αλγόριθμος Δυαδικού Φίλτρου Kalman με MLP δίκτυο στην προσπάθεια επίλυσης του
description: The goal of this thesis is to present Dual Kalman filter and how its performance gets improved by the usage of Neural Network when outliers are present in the data. Firstly, the description of evolutionary algorithms, a category of metaheuristic algorithms, is given along with an analytic presentation of Stochastic Fractal Search (SFS). Then, Neural Networks and related concepts are described. Clarification over their function, Backpropagation learning algorithm, Perceptron and Multilayer Perceptron (MLP), theoretical results which justify the effectiveness of MLP are given. Moreover, the way that evolutionary algorithms improve the network’s learning and MLP-SFS model is presented. The third part is concerned with Kalman Filter. There is a description of Dual Kalman Filter and also the Kalman Filter algorithm enhanced with an MLP network. Finally, the problem of effective connectivity over brain’s active regions is defined and a hybrid algorithm of Dual Kalman Filter and MLP is practiced in an attempt to find its solution
Badminton World Federation - Life Skills Project
Creators: name: Sellars, Paul
name: Dohme, Lea-Cathrin
name: Mellalieu, Stephen
name: Camiré, Martin
Publisher: name: Cardiff Metropolitan University
Year: 2021
Subjects: subject: 170114 Sport and Exercise Psychology
subject: FOS: Psychology

description: Facilitating dual career badminton players’ life skills development through the education of their entourage
The current study/project had two objectives.
First, to understand the knowledge and use of life skills of adolescent badminton players and their entourage (parents/guardians and badminton staff) within a badminton setting.
Second, to develop and evaluate an online educational program aimed at enhancing entourage members’ knowledge of, and ability to promote dual career badminton players’ life skills development.

Presented here are infographics giving a overview and practical implications of the project alongside a narrative abstract.
Nonlinear dynamics of quantum dot nuclear spins
Creators: name: Maletinsky, P.
name: Lai, C. W.
name: Badolato, A.
name: Imamoglu, A.
Publisher: name: arXiv
Year: 2006
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: We report manifestly nonlinear dependence of quantum dot nuclear spin polarization on applied magnetic fields. Resonant absorption and emission of circularly polarized radiation pumps the resident quantum dot electron spin, which in turn leads to nuclear spin polarization due to hyperfine interaction. We observe that the resulting Overhauser field exhibits hysteresis as a function of the external magnetic field. This hysteresis is a consequence of the feedback of the Overhauser field on the nuclear spin cooling rate. A semi-classical model describing the coupled nuclear and electron spin dynamics successfully explains the observed hysteresis but leaves open questions for the low field behaviour of the nuclear spin polarization.
description: 7 pages, 4 figures
Semantic elicitation: Epistemic indefinites
Creators: name: Kipkoech, Linus
name: Bossi, Madeline
Publisher: name: California Language Archive, University of California, Berkeley
Year: 2022
Subjects: subject: sgc

description: One .mp4 file and one .pdf file. Elicitation of semantic properties of epistemic indefinites including contexts with singleton extensions and Binder Roof Constraint contexts.
Tamm states and nonlinear surface modes in photonic crystals
Creators: name: Morrison, Steven K.
name: Kivshar, Yuri S.
Publisher: name: arXiv
Year: 2006
Subjects: subject: Optics (physics.optics)
subject: Pattern Formation and Solitons (nlin.PS)
subject: FOS: Physical sciences

description: We predict the existence of surface gap modes, known as Tamm states for electronic systems, in truncated photonic crystals formed by two types of dielectric rods. We investigate the energy threshold, dispersion, and modal symmetries of the surface modes, and also demonstrate the existence and tunability of nonlinear Tamm states in binary photonic crystals with nonlinear response.
description: 11 pages, 3 figures, submitted to Optics Communications
A Hybrid Genetic-Fuzzy Controller for a 14-inches Astronomical Telescope Tracking
Creators: name: Eid, Doaa
name: Attia, Abdel-Fattah
name: Elmasry, Said
name: Helmy, Islam
Publisher: name: arXiv
Year: 2021
Subjects: subject: Systems and Control (eess.SY)
subject: Instrumentation and Methods for Astrophysics (astro-ph.IM)
subject: FOS: Electrical engineering, electronic engineering, information engineering
subject: FOS: Physical sciences

description: The performance of on telescope depend strongly on its operating conditions. During pointing the telescope can move at a relatively high velocity, and the system can tolerate trajectory position errors higher than during tracking. On the contrary, during tracking Alt-Az telescopes generally move slower but still in a large dynamic range. In this case, the position errors must be as close to zero as possible. Tracking is one of the essential factors that affect the quality of astronomical observations. In this paper, a hybrid Genetic-Fuzzy approach to control the movement of a two-link direct-drive Celestron telescope is introduced. The proposed controller uses the Genetic algorithm (GA) for optimizing a fuzzy logic controller (FLC) to improve the tracking of the 14-inches Celestron telescope of the Kottamia Astronomical Observatory (KAO). The fuzzy logic input is a vector of the position error and its rate of change, and the output is torque. The GA objective function used here is the Integral Time Absolute Error (ITAE). The proposed method is compared with a conventional Proportional-Differential (PD) controller, an optimized PD controller with a GA, and a Fuzzy controller. The results show the effectiveness of the proposed controller to improve the dynamic response of the overall system.
description: 10 pages, 3 tables, 9 figures, accepted for publication in Journal of Astronomical Instrumentation (JAI)
Non-negative Wigner functions in prime dimensions
Creators: name: Gross, David
Publisher: name: arXiv
Year: 2007
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: According to a classical result due to Hudson, the Wigner function of a pure, continuous variable quantum state is non-negative if and only if the state is Gaussian. We have proven an analogous statement for finite-dimensional quantum systems. In this context, the role of Gaussian states is taken on by stabilizer states. The general results have been published in [D. Gross, J. Math. Phys. 47, 122107 (2006)]. For the case of systems of odd prime dimension, a greatly simplified proof can be employed which still exhibits the main ideas. The present paper gives a self-contained account of these methods.
description: 5 pages. Special case of a result proved in quant-ph/0602001. The proof is greatly simplified, making the general case more accessible. To appear in Appl. Phys. B as part of the proceedings of the 2006 DPG Spring Meeting (Quantum Optics and Photonics section)
Special Supplement to Volume 18 The Experience of Indian Residential Schooling
Creators: name: Ing, N. Rosalyn
name: Bull, Linda R.
Publisher: name: Canadian Journal of Native Education
Year: 2021

description: Two major research reports constitute a special supplemental issue of CanadianJournal of Native Education, to be published in Fall, 1991. Subscribers to Volume 18 and Volume 19 will receive this supplement, which will not be sold separately.
description: Canadian Journal of Native Education, Vol. 18 No. 1 (1991)
Grammatical elicitation: Epistemic indefinites and raising
Creators: name: Yegon, Kiplangat
name: Bossi, Madeline
Publisher: name: California Language Archive, University of California, Berkeley
Year: 2022
Subjects: subject: sgc

description: One .mp4 file and one .pdf file. Elicitation of syntactic properties of epistemic indefinites (e.g. possession, definiteness). Elicitation of embedding verbs with raising of various constituents out of the embedded clause. Exploration of Weak Crossover effects.
Precision physics with a wide band super neutrino beam
Creators: name: Barger, V.
name: Dierckxsens, M.
name: Diwan, M.
name: Huber, P.
name: Lewis, C.
name: Marfatia, D.
name: Viren, B.
Publisher: name: arXiv
Year: 2006
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: High Energy Physics - Experiment (hep-ex)
subject: FOS: Physical sciences

description: We carry out a state-of-the-art assessment of long baseline neutrino oscillation experiments with wide band beams. We describe the feasibility of an experimental program using existing high energy accelerator facilities, a new intense wide band neutrino beam (0-6 GeV) and a proposed large detector in a deep underground laboratory. We find that a decade-long program with 1 MW operation in the neutrino mode and 2 MW operation in the antineutrino mode, a baseline as long as the distance between Fermilab and the Homestake mine (1300 km) or the Henderson mine (1500 km), and a water Cherenkov detector with fiducial mass of about 300 kT has optimum sensitivity to θ_{13}, the mass hierarchy and to neutrino CP violation at the 3σC.L. for \sin^22θ_{13}>0.008. This program is capable of breaking the eight-fold degeneracy down to the octant degeneracy without additional external input.
description: 20 pages, 11 figures. Version to appear in PRD
Low- and Medium-Dispersion Spectropolarimetry of Nova V475 Sct (Nova Scuti 2003): Discovery of an Asymmetric High-Velocity Wind in a Moderately Fast Nova
Creators: name: Kawabata, Koji S.
name: Ohyama, Youichi
name: Ebizuka, Noboru
name: Takata, Tadafumi
name: Yoshida, Michitoshi
name: Isogai, Mizuki
name: Norimoto, Yuji
name: Okazaki, Akira
name: Saitou, Masashi S.
Publisher: name: arXiv
Year: 2006
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: We present low-resolution ($R\sim 90$) and medium-resolution ($R\sim 2500$) spectropolarimetry of Nova V475 Sct with the HBS instrument, mounted on the 0.91-m telescope at the Okayama Astrophysical Observatory, and with FOCAS, mounted on the 8.2-m Subaru telescope. We estimated the interstellar polarization toward the nova from the steady continuum polarization components and H$α$ line emission components. After subtracting the interstellar polarization component from the observations, we found that the H$α$ emission seen on 2003 October 7 was clearly polarized. In the polarized flux spectrum, the H$α$ emission had a distinct red wing extending to $\sim +4900$ km s$^{-1}$ and a shoulder around $+3500$ km s$^{-1}$, showing a constant position angle of linear polarization $θ_{\rm *}\simeq 155\arcdeg\pm 15\arcdeg$. This suggests that the nova had an asymmetric outflow with a velocity of $v_{\rm wind}\simeq 3500$ km s$^{-1}$ or more, which is six times higher than the expansion velocity of the ionized shell at the same epoch. Such a high-velocity component has not previously been reported for a nova in the `moderately fast' speed class. Our observations suggest the occurrence of violent mass-loss activity in the nova binary system even during the common-envelope phase. The position angle of the polarization in the H$α$ wing is in good agreement with that of the continuum polarization found on 2003 September 26 ($p_{\rm *}\simeq 0.4$--0.6 %), which disappeared within the following 2 d. The uniformity of the PA between the continuum polarization and the wing polarization on October 7 suggests that the axis of the circumstellar asymmetry remained nearly constant during the period of our observations.
description: 27 pages, 7 figures, accepted for publication in AJ
Categorization of Coronal Mass Ejection Driven Sheath Regions: Characteristics of STEREO Events
Creators: name: Salman, T. M.
name: Lugaz, N.
name: Winslow, R. M.
name: Farrugia, C. J.
name: Jian, L. K.
name: Galvin, A. B.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: Space Physics (physics.space-ph)
subject: FOS: Physical sciences

description: We present a comprehensive statistical analysis of 106 sheath regions driven by coronal mass ejections (CMEs) and measured near 1 AU. Using data from the STEREO probes, this extended analysis focuses on two discrete categorizations. In the first categorization, we investigate how the generic features of sheaths change with their potential formation mechanisms (propagation and expansion sheaths), namely, their associations with magnetic ejectas (MEs) which are primarily expanding or propagating in the solar wind. We find propagation sheaths to be denser and driven by stronger MEs, whereas expansion sheaths are faster. Exploring the temporal profiles of these sheaths with a superposed epoch technique, we observe that most of the magnetic field and plasma signatures are more elevated in propagation sheaths relative to expansion sheaths. The second categorization is based on speed variations across sheaths. Employing linear least squares regression, we categorize four distinct speed profiles of the sheath plasma. We find that the associated shock properties and solar cycle phase do not impact the occurrence of such variations. Our results also highlight that the properties of the driving MEs are a major source of variability in the sheath properties. Through logistic regression, we conclude that the magnetic field strength and the ME speed in the frame of the solar wind are likely drivers of these speed variations.
ESiWACE Newsletter 07/2019
Creators: name: Neumann, Philipp
Publisher: name: Zenodo
Year: 2019
Subjects: ESiWACE
climate
weather
centre of excellence
HPC
high performance computing

description: To subscribe to/unsubscribe from this newsletter, please visit https://lists.dkrz.de/mailman/listinfo/esiwace-external
 You find further details on ESiWACE at www.esiwace.eu.
 All newsletters are also available at www.esiwace.eu/newsletter
Ζητήματα προστασίας διακριτικών γνωρισμάτων φήμης και ειδικότερα του σήματος φήμης
Creators: name: Ορταντζόγλου, Μαρία Αθανασίου
Publisher: name: Aristotle University of Thessaloniki
Year: 2020
Subjects: σήμα
φήμη
mark
trademark
reputation

description: Σκοπός της διατριβής ήταν η μελέτη ενός ιδιαίτερου είδους σήματος, του σήματος φήμης και της διευρυμένης προστασίας που απολαμβάνει, λόγω των χαρακτηριστικών του, έναντι μεταγενέστερων σημάτων. Τα σήματα φήμης προστατεύονται τόσο σε ενωσιακό όσο και σε εθνικό επίπεδο με ειδική πρόβλεψη. Στα σήματα αυτά ο νομοθέτης παρέχει διευρυμένη νομική προστασία, πέρα της προβλεπόμενης για τα κοινά διακριτικά γνωρίσματα, με σκοπό αφενός την αποτροπή του παρασιτικού ανταγωνισμού από τρίτους, πλην του δικαιούχου, συνισταμένου στην εμπορική αξιοποίηση της φήμης του σήματος προς το ίδιο αθέμιτο όφελος και αφετέρου του κινδύνου υπονόμευσης της ιδιαίτερης διακριτικής δύναμης των σημάτων αυτών
description: The aim of the present thesis was the study a particular type of mark is the reputation mark and the extended protection it enjoys, due to its characteristics, against subsequent marks. Reputation marks are protected at both EU and national level with special provision. In such trademarks the legislator provides extended legal protection, in addition to that provided for in the common distinctive features, in order to prevent parasitic competition from third parties other than the proprietor, consisting in the commercial exploitation of the reputation of the trademark for the same unfair advantage and on the other. risk of undermining the distinctive power of these signals
(Not) Summing over Kaluza-Kleins
Creators: name: Hirn, Johannes
name: Sanz, Veronica
Publisher: name: arXiv
Year: 2007
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: Models in extra-dimensions have unique features. Many of their surprising properties simply result from the underlying 5D structure. This structure shows up as ``Sum Rules'' involving the whole tower of Kaluza-Kleins. In this paper, we present a holographic shortcut and derive these results without solving the eigenvalue problem: we express 4D physical quantities directly in terms of the 5D metric. In warped space, one can go further and isolate the effect of the new physics sector. This method can be used for any 5D model, and we apply it here to the case of holographic QCD and technicolor.
Nodal profile control for networks of geometrically exact beams
Creators: name: Leugering, Günter
name: Rodriguez, Charlotte
name: Wang, Yue
Publisher: name: arXiv
Year: 2021
Subjects: subject: Optimization and Control (math.OC)
subject: Analysis of PDEs (math.AP)
subject: FOS: Mathematics
subject: 35L50, 35R02, 93B05, 93C20, 35Q74, 74K10

description: In this work, we consider networks of so-called geometrically exact beams, namely, shearable beams that may undergo large motions. The corresponding mathematical model, commonly written in terms of displacements and rotations expressed in a fixed basis (Geometrically Exact Beam model, or GEB), has a quasilinear governing system. However, the model may also be written in terms of intrinsic variables expressed in a moving basis attached to the beam (Intrinsic GEB model, or IGEB) and while the number of equations is then doubled, the latter model has the advantage of being of first-order, hyperbolic and only semilinear. First, for any network, we show the existence and uniqueness of semi-global in time classical solutions to the IGEB model (i.e., for arbitrarily large time intervals, provided that the data are small enough). Then, for a specific network containing a cycle, we address the problem of local exact controllability of nodal profiles for the IGEB model -- we steer the solution to satisfy given profiles at one of the multiple nodes by means of controls applied at the simple nodes -- by using the constructive method of Zhuang, Leugering and Li [Exact boundary controllability of nodal profile for Saint-Venant system on a network with loops, in J. Math. Pures Appl., 2018]. Afterwards, for any network, we show that the existence of a unique classical solution to the IGEB network implies the same for the corresponding GEB network, by using that these two models are related by a nonlinear transformation. In particular, this allows us to give corresponding existence, uniqueness and controllability results for the GEB network.
description: 33 pages, 6 figures
Theory of antiferromagnetism in the electron-doped cuprate superconductors
Creators: name: Yan, Xin-Zhong
name: Yuan, Qingshan
name: Ting, C. S.
Publisher: name: arXiv
Year: 2006
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: Superconductivity (cond-mat.supr-con)
subject: FOS: Physical sciences

description: On the basis of the Hubbard model, we present the formulation of antiferromagnetism in electron-doped cuprates using the fluctuation-exchange approach. Taking into account the spin fluctuations in combination with the impurity scattering effect due to the randomly distributed dopant-atoms, we investigate the magnetic properties of the system. It is shown that the antiferromagnetic transition temperature, the onset temperature of the pseudogap formation, the single particle spectral density, and the staggered magnetization obtained by the present approach are in very good agreement with the experimental results. The distribution function in momentum space at very low temperature is observed to differ significantly from that of the Fermi liquid. Also, we find zero-energy peak in the density of states (DOS) of the antiferromagnetic phase. This DOS peak is sharp in the low doping regime, and disappears near the optimal doping where the AF order becomes weak.
description: 12 pages, 19 figures