cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
From Spacetime to Worldsheet: Four point correlators
Creators: name: David, Justin R.
name: Gopakumar, Rajesh
Publisher: name: arXiv
Year: 2006
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: The Schwinger representation gives a systematic procedure for recasting large N field theory amplitudes as integrals over closed string moduli space. This procedure has recently been applied to a class of free field four point functions by Aharony, Komargodski and Razamat, to study the leading terms in the putative worldsheet OPE. Here we observe that the dictionary between Schwinger parameters and the cross ratio of the four punctured sphere actually yields an explicit expression for the full worldsheet four point correlator in many such cases. This expression has a suggestive form and obeys various properties, such as crossing symmetry and mutual locality, expected of a correlator in a two dimensional CFT. Therefore one may take this to be a candidate four point function in a worldsheet description of closed strings on highly curved AdS_5 \times S^5. The general framework, that we develop for computing the relevant Strebel differentials, also admits a systematic perturbation expansion which would be useful for studying more general four point correlators.
description: 41 pages, uses JHEP3.cls
Μελέτη νανοηλεκτρονικών διατάξεων τρανζίστορ μονού ηλεκτρονίου (single electron transistor -SET) με προσομοίωση
Creators: name: Βενέτη, Αικατερίνη Θεολόγη
Publisher: name: Aristotle University of Thessaloniki
Year: 2015
Subjects: Τρανζίτστορ μονού ηλεκτρονίου
Προσομοίωση
Νανοηλεκτρονική
Single electron transistor
Simulation
Nanoelectronics

description: Στην εργασία αυτή πραγματοποιείται η κατασκευή νέων κυκλωμάτων που βασίζονται σε τρανζίστορ μονού ηλεκτρονίου και προσομοίωση της λειτουργίας τους. Το κύριο εργαλείο που χρησιμοποιείται είναι ο προσομοιωτής SECS (SingleElectronCircuitSimulator).Μετά από μια εκτενή εισαγωγή στη φυσική των τρανζίστορ μονού ηλεκτρονίου και στις μεθόδους προσομοίωσης, το κύριο μέρος της εργασίας αποτελείται από την υλοποίηση των λογικών κυκλωμάτων. Αρχικά, παρουσιάζεται η πύληANDτριών εισόδων και ο αποκωδικοποιητή 2-4, τα δομικά στοιχεία για τα πιο πολύπλοκα κυκλώματα που υλοποιούνται στη συνέχεια. Τα παραπάνω κυκλώματα συνδυάζονται για την κατασκευή τουνέου κυκλώματος του αποκωδικοποιητή 2-4 με επίτρεψη. Η λειτουργία του αποκωδικοποιητή 2-4 με επίτρεψη ελέγχεται πέρα από θερμοκρασίες 0.1 Κ και σε μη μηδενικές θερμοκρασίες και προσδιορίζεται ο θόρυβος που εμφανίζεται στα αποτελέσματα. Τέλος, δυο αποκωδικοποιητές 2-4 με επίτρεψη, συνδυάζονται για την κατασκευή του αποκωδικοποιητή 3-8, αποδεικνύοντας την επεκτασιμότητα των κυκλωμάτωνSET. Για κάθε κύκλωμα γίνεται προσδιορισμός και αναλυτική καταγραφή των παραμέτρων όπως τιμές χωρητικότητας, τιμές των αντιστάσεων, τάσεις λειτουργίας, δυναμικά πολώσεως, συχνότητες εισόδου των λογικών παραμέτρων 0 και 1, ενώ πέρα από την επαλήθευση της σωστής λειτουργίας, εξετάζονται και τα αποτελέσματα της ενεργειακής συμπεριφοράς των κυκλωμάτων. Όλα τα κυκλώματα που προσομοιώνονται λειτουργούν σε συνθήκες θερμοδυναμικής ισορροπίας.
description: In this thesis, the realization of new single electron transistor based circuits and the simulation of their operation is presented. The main tool used towards this aim is the SECSSimulator (SingleElectronCircuitSimulator).A detailed description of the physics behind single electron transistors and of the simulation methods is provided in the first chapters, followed by the construction of the new logic circuits. Initially, the 3 input AND gate and the 2-4 decoder are presented, which constitute building blocks for more complex circuits. The aforementioned circuits are then combined to create the novel 2-4 decoder with enable. The operation of the decoder is verified in 0.1 K and additionally in non-zero temperatures.Finally, two 2-4 decoders with enable are combined to construct the new 3-8 decoder, proving the concept of expandability in SET circuits. The parameters of every circuit, such as the capacitor and tunnel junction capacitance, the tunnel junction resistances, the operation voltages, the frequencies of the logic parameters 0 and 1, are well defined. The operation of the circuits is verified and the energetics of each one are examined. All the circuits are found to operate in thermodynamic equilibrium.
The GOODS-MUSIC sample: a multicolour catalog of near-IR selected galaxies in the GOODS-South field
Creators: name: Grazian, A.
name: Fontana, A.
name: De Santis, C.
name: Nonino, M.
name: Salimbeni, S.
name: Giallongo, E.
name: Cristiani, S.
name: Gallozzi, S.
name: Vanzella, E.
Publisher: name: arXiv
Year: 2006
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: We present a high quality multiwavelength (from 0.3 to 8.0 micron) catalog of the large and deep area in the GOODS Southern Field covered by the deep near-IR observations obtained with the ESO VLT. The catalog is entirely based on public data: in our analysis, we have included the F435W, F606W, F775W and F850LP ACS images, the JHKs VLT data, the Spitzer data provided by IRAC instrument (3.6, 4.5, 5.8 and 8.0 micron), and publicly available U-band data from the 2.2ESO and VLT-VIMOS. We describe in detail the procedures adopted to obtain this multiwavelength catalog. In particular, we developed a specific software for the accurate "PSF-matching" of space and ground-based images of different resolution and depth (ConvPhot), of which we analyse performances and limitations. We have included both z-selected, as well as Ks-selected objects, yielding a unique, self-consistent catalog. The largest fraction of the sample is 90% complete at z~26 or Ks~23.8 (AB scale). Finally, we cross-correlated our data with all the spectroscopic catalogs available to date, assigning a spectroscopic redshift to more than 1000 sources. The final catalog is made up of 14847 objects, at least 72 of which are known stars, 68 are AGNs, and 928 galaxies with spectroscopic redshift (668 galaxies with reliable redshift determination). We applied our photometric redshift code to this data set, and the comparison with the spectroscopic sample shows that the quality of the resulting photometric redshifts is excellent, with an average scatter of only 0.06. The full catalog, which we named GOODS-MUSIC (MUltiwavelength Southern Infrared Catalog), including the spectroscopic information, is made publicly available, together with the software specifically designed to this end.
description: Accepted for publication in Astronomy and Astrophysics, uses aa.cls, 20 pages, 16 figures. Further information at http://lbc.oa-roma.inaf.it/goods
Many-spin entanglement in multiple quantum NMR with a dipolar ordered initial state
Creators: name: Lazarev, Ilia D.
name: Feldman, Edward. B.
Publisher: name: arXiv
Year: 2020
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: Multiple quantum (MQ) NMR with a dipolar ordered initial state opens new possibilities for the exploration of many-spin entanglement. In this paper, we investigate many-spin entanglement in a gas of spin-carrying molecules (atoms) in nanocavities in the conditions of MQ NMR with a dipolar ordered initial state. The second moment of the distribution of the intensities of MQ NMR coherences, which provides a lower bound on the quantum Fisher information, is used for an estimate of the number of the entangled spins. Many-spin entanglement is investigated at different temperatures and different numbers of spins.
Modelling forest development in the Mackenzie Basin under a changing climate
Creators: name: Hartley, Mary Isobel
Publisher: name: University of British Columbia
Year: 2009

description: The purpose of this study was to explore relationships between baseline climate conditions (1951- 1980), and forest composition and productivity, over the Mackenzie Basin at the forest inventory unit level, for use in the development of a forest productivity model. The Mackenzie Basin Forest Productivity model (MBFP model) was then constructed to project the climate-related forest attributes through climate change conditions, as predicted by global circulation models (GCMs). The tree species studied were black and white spruce (Picea mariana (Mill.) B.S.P. and Picea glauca (Moench) Voss.), jack pine (Pinus banksiana Lamb.), lodgepole pine (Pinus contorta Dougl.) trembling aspen (Populus tremuloides Michx.), and paper birch (Betulapapyrifera Marsh.). Only 18% of the area within the Mackenzie Basin had adequate forest inventory information for use in building the climate relationships and the MBFP model. The aggregation method used for multiple stand records within inventory units was described, with the transfer of information across scales recognized as an area of concern. Each species was assigned to age groups; productivities in the first three age groups were related to the baseline climate conditions (1951-80) using multiple linear regression techniques at the inventory unit level. The relative proportions of each species in each inventory unit were also related to the baseline climate conditions (1951-80) in a similar manner. The relationships for species productivity varied in R² values from 0.09 (MSE[sub e][sup 1/2] 5.83m³/ha) to 0.48 (MSE[sub e][sup 1/2] 4.04 m³/ha). The relationships for species' relative proportions in inventory units varied in R2 values from 0.14 (MSE[sub e][sup 1/2] 0.03) to 0.41 (MSE[sub e][sup 1/2] 0.16). The model was built using the GRASS GIS environment supported on the Linux operating system. Productivity, mortality (through surrounding conditions and fire), and establishment were represented in relation to climate in the model. The approaches used in modelling these processes were described and source code provided. Suggestions for calibrating the model to baseline climates provided by various Global Circulation Models (GCMs) were made and a design for a sensitivity analysis was given. Results from running the model were not provided due to limitations reached in the fire module imposed by the modelling environment. Overcoming these limitations was considered to be beyond the scope of this research.
Σφαιρική Ανάλυση σε Αρμονικές Ομάδες ΑΝ
Creators: name: Κουσίδης, Παναγιώτης Ιωάννη
Publisher: name: Aristotle University of Thessaloniki
Year: 2015
Subjects: Αρμονικές Ομάδες ΑΝ
Lp-συνέχεια
Πολλαπλασιαστές
Harmonic AN Groups
Lp-boundedness
Multipliers

description: Οι αρμονικές ομάδες ΑΝ έχουν μελετηθεί από αρκετούς ερευνητές τα τελευταία χρόνια. Αυτές οι επιλύσιμες ομάδες Lie περιλαμβάνουν όλους τους συμμετρικούς χώρους μη-συμπαγούς τύπου και τάξης 1. Χρησιμοποιώντας την σφαιρική ανάλυση, δηλαδή την ανάλυση των ακτινικών συναρτήσεων, θα συμπεράνουμε πως είναι παρόμοια με την ανάλυση στους υπερβολικούς χώρους. Θα δώσουμε έμφαση στο ότι η σφαιρική ανάλυση είναι συγκεκριμένη περίπτωση της συναρτησιακής ανάλυσης Jacobi. Επιπλέον, θα παρουσιάσουμε μια σειρά αποτελεσμάτων, που απεικονίζουν την ομοιότητα με τους συμμετρικούς χώρους, όπως το φαινόμενο Kunze-Stein και τις ελάχιστες συνθήκες των θετικών ακτινικών πυρήνων συνέλιξης για την Lp-συνέχεια και την ασθενή L1 συνέχεια. Επιπροσθέτως, θα αναφέρουμε μια ευρύτερη κλάση, η οποία αποτελείται από όλες τις συναρτήσεις του τελεστή Laplace-Beltrami, που είναι τουλάχιστον φραγμένες στον L2 και θα μελετήσουμε το ανάλογο του κλασικού προβλήματος των πολλαπλασιαστών. Πιο συγκεκριμένα, στο Κεφάλαιο 1 θα μελετήσουμε τη βασική δομή των αρμονικών ομάδων AN και στο Κεφάλαιο 2 τη βασική σφαιρική αρμονική ανάλυση. Στο Κεφάλαιο 3 θα θεμελιώσουμε το ανάλογο του κριτηρίου Herz για την Lp και ασθενή L1 συνέχεια θετικών ακτινικών πυρήνων συνέλιξης, με αποτέλεσμα το σφαιρικό φαινόμενο Kunze-Stein, αλλά και την ασθενή L1 συνέχεια της μεγιστικής συνάρτησης Hardy-Littlewood. Τέλος, στο Κεφάλαιο 4 θα παρουσιάσουμε τους Lp συνεχείς ακτινικούς πολλαπλασιαστές.
description: Harmonic AN groups have been studied by several authors in the past years. These solvable Lie groups include all symmetric spaces of noncompact type and rank 1.Using spherical analysis, namely the analysis of radial functions, we will conclude that it is quite similar to the hyperbolic space case. We will emphasize that spherical analysis is a particular case of the Jacobi analysis. Furthermore, we will present a series of results, which illustrates the similarity with symmetric spaces, such as the Kunze-Stein phenomenon and the minimal conditions of positive radial convolution kernels for Lp-boundedness and weak L1-boundedness. In addition, we will mention a wider class, that consists of all the functions of the Laplace-Beltrami operator that are at least bounded on L2 and we will study the analogue of the classical Lp-multiplier problem. Specifically, on Chapter 1 we will study the basic structure of harmonic AN groups and on Chapter 2 the basic spherical harmonic analysis. On Chapter 3 we will establish the analogue of the Herz criterion for the Lp-boundedness and the weak L1-boundedness of positive radial convolution kernels, and get as a result a spherical Kunze-Stein phenomenon and the weak L1-bounded of the Hardy-Littlewood maximal function. Finally, on Chapter 4 we will present the radial Lp-multipliers.
Η Μεταρρυθμιστική Παιδαγωγική στη Γερμανία και το παιδαγωγικό έργο του Hugo Gaudig (1860-1923): όψεις, απόψεις και επιδράσεις
Creators: name: Κιοσσέ, Ειρήνη Ιωάννη
Publisher: name: Aristotle University of Thessaloniki
Year: 2015
Subjects: Σχολείο Εργασίας
Εκπαίδευση θηλέων
Αυτενέργεια
New Education
Hugo Gaudig
Female Education
Reformpädagogik
Selbsttätigkeit
Mädchenschule

description: Σκοπός της διατριβής ήταν η μελέτη της Μεταρρυθμιστικής Παιδαγωγικής στη Γερμανία και συγκεκριμένα το παιδαγωγικό και διδακτικό έργο του Hugo Gaudig. Εξετάσαμε τις παιδαγωγικές απόψεις του γερμανού παιδαγωγού αφενός αναφορικά με το Σχολείο Εργασίας και αφετέρου αναφορικά με την εκπαίδευση των θηλέων και των διδασκαλισσών, με την οποία ασχολήθηκε διεξοδικά. Στην εργασία αυτή, προσπαθήσαμε να αποκρυσταλλώσουμε τις απόψεις του για το πρόγραμμα, την οργάνωση και το περιεχόμενο της γυναικείας εκπαίδευσης. Ασχοληθήκαμε επιπλέον με την απήχηση που είχε το παιδαγωγικό και διδακτικό έργο του Gaudig διεθνώς, καθώς επίσης και με τις επιδράσεις που άσκησε στους Έλληνες παιδαγωγούς που βρίσκονται και δραστηριοποιούνται τις πρώτες δεκαετίες του 20ου αιώνα στη Γερμανία.
description: The aim of the present paper was the study of New Education in Germany and especially on the pedagogical work of Hugo Gaudig. His pedagogical theory as far as the “Arbeitschule” is concerned, the female education, the female teacher training program and its content consist crucial aspects of Gaudig’s work which are under examination in this particular thesis. The global effect of Gaudig’s pedagogical and teaching work and the influence it posed in Greek pedagogists who were occupied in Germany in the first decades of the 20th century is an integral part of our research as well.
Skyrmion-antiskyrmion droplets in a chiral ferromagnet
Creators: name: Sisodia, Naveen
name: Muduli, Pranaba Kishor
name: Papanicolaou, Nikos
name: Komineas, Stavros
Publisher: name: arXiv
Year: 2020
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: We find numerically skyrmionic textures with skyrmion number Q=0 in ferromagnets with the Dzyaloshinskii-Moriya interaction and perpendicular anisotropy. These have the form of a skyrmion-antiskyrmion pair and may be called chiral droplets. They are stable in an infinite film as well as in disc-shaped magnetic elements. Droplets are found for values of the parameters close to the transition from the ferromagnetic to the spiral phase. We study their motion under spin-transfer torque. They move in the direction of the spin flow and, thus, their dynamics are drastically different than the Hall dynamics of the standard Q=0 skyrmion.
Time evolution of the radio continuum of young starbursts: The importance of synchrotron emission
Creators: name: Hirashita, H.
name: Hunt, L. K.
Publisher: name: arXiv
Year: 2006
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: We investigate the radio spectral energy distributions (SEDs) of young star-forming galaxies and how they evolve with time. The duration and luminosity of the nonthermal radio emission from supernova remnants (SNRs) are constrained by using the observational radio SEDs of SBS 0335-052 and I Zw 18, which are the two lowest-metallicity blue compact dwarf galaxies in the nearby universe. The typical radio ``fluence'' for SNRs in SBS 0335-052, that is the radio energy emitted per SNR over its radiative lifetime, is estimated to be $\sim 6$--$22\times 10^{22} {\rm W Hz^{-1} yr}$ at 5 GHz. On the other hand, the radio fluence in I Zw 18 is $\sim 1$--$3\times 10^{22} {\rm W Hz^{-1} yr}$ at 5 GHz. We discuss the origin of this variation and propose scaling relations between synchrotron luminosity and gas density. We have also predicted the time dependence of the radio spectral index and of the spectrum itself, for both the ``active'' (SBS 0335-052) and ``passive'' (I Zw 18) cases. These models enable us to roughly age date and classify radio spectra of star-forming galaxies into active/passive classes. Implications for high-z galaxy evolution are also discussed.
description: 18 pages, 8 figures, accepted by A&A
Welsh Wreck Web Research Project (North Cardigan Bay). On-line research into the wreck of the: Lily (yacht)
Creators: name: Davies, Gareth J.S.
Publisher: name: Archaeology Data Service
Year: 2024

description: Welsh Wreck Web Research Project unpublished report series, 1
description: The Lily was built in 1880 in Wivenhoe, Essex and owned by Dr J.H. Lister. While returning to Barmouth on May 22 1888, the Lily struck the submerged wreck of the Eulomene which had run aground and wrecked on Jan 29 1884. The Lily was badly holed and sank 2 hours later.
Συγκριτική μελέτη της Αρτικαΐνης – Λιδοκαΐνης στην υποβλεννογόνια αναισθησία του πρώτου μόνιμου γομφίου της κάτω γνάθου
Creators: name: Ματούλας, Ευθύμιος Αθανασίου
Publisher: name: Aristotle University of Thessaloniki
Year: 2015
Subjects: Λιδοκαΐνη
Αρτικαΐνη
Τοπική δι’ εμποτίσεως αναισθησία
Lidocaine
Articaine
Buccal infiltration

description: Σκοπός της διατριβής ήταν η σύγκριση της αρτικαΐνης 4% (με 1:100000 επινεφρίνη) και της λιδοκαΐνης 2% (με 1: 80000 επινεφρίνη) στην επίτευξη πολφικής αναισθησίας των πρώτων μόνιμων γομφίων της κάτω γνάθου μόνο με παρειακή τοπική διʼ εμποτίσεως έγχυση. Σε σαράντα υγιείς ενήλικες εθελοντές διενεργήθηκεαναισθησία και με τα δύο διαλύματα, με τυχαία σειρά και με μία τουλάχιστον εβδομάδα διαφορά μεταξύ τους. Ο έλεγχος της αναισθητοποίησης πραγματοποιήθηκε με ηλεκτρικό πολφοδοκιμαστήρα. Τα αποτελέσματα της μελέτης έδειξαν σημαντικά υψηλότερα ποσοστά επιτυχίας της αρτικαΐνης έναντι της λιδοκαΐνης στην επίτευξη πολφικής αναισθησίας των εξεταζόμενων δοντιών. Επιπλέον, η διάρκεια της αναισθησίας ήταν μεγαλύτερη στις περιπτώσεις που χορηγήθηκε αρτικαΐνη και η διαφορά ήταν στατιστικώς σημαντική. Συμπερασματικά, η αρτικαΐνη υπερέχει της λιδοκαΐνης και μπορεί να χρησιμοποιηθεί με ικανοποιητικά αποτελέσματα για την αναισθητοποίηση του πρώτου μόνιμου γομφίου της κάτω γνάθου με τοπική δι’ εμποτίσεως τεχνική.
description: The aim of the present thesis was to compare the efficacy of buccal infiltration using articaine 4% (with 1:100000 epinephrine) and lidocaine 2% (with 1:80000 epinephrine) in achieving mandibular first molar pulp anesthesia. Forty healthy adult volunteers received local anesthesia with both anesthetic solutions in a randomized order. Injections were given at least 1 week apart from each other. Electronic pulp testing was undertaken to confirm pulpal anesthesia. According to the results of the present study, articaine showed significantly higher success rate in obtaining pulpal anesthesia. In addition, anesthesia duration was longer after articaine infiltration than lidocaine infiltration. The difference was statistically significant. In conclusion, buccal infiltration with articaine is superior to lidocaine in achieving first molar pulpal anesthesia.
Missing values : processing with the Kohonen algorithm
Creators: name: Cottrell, Marie
name: Letrémy, Patrick
Publisher: name: arXiv
Year: 2007
Subjects: subject: Statistics Theory (math.ST)
subject: Neural and Evolutionary Computing (cs.NE)
subject: FOS: Mathematics
subject: FOS: Computer and information sciences

description: The processing of data which contain missing values is a complicated and always awkward problem, when the data come from real-world contexts. In applications, we are very often in front of observations for which all the values are not available, and this can occur for many reasons: typing errors, fields left unanswered in surveys, etc. Most of the statistical software (as SAS for example) simply suppresses incomplete observations. It has no practical consequence when the data are very numerous. But if the number of remaining data is too small, it can remove all significance to the results. To avoid suppressing data in that way, it is possible to replace a missing value with the mean value of the corresponding variable, but this approximation can be very bad when the variable has a large variance. So it is very worthwhile seeing that the Kohonen algorithm (as well as the Forgy algorithm) perfectly deals with data with missing values, without having to estimate them beforehand. We are particularly interested in the Kohonen algorithm for its visualization properties.
Το έγκλημα της ψευδούς βεβαίωσης (242 ΠΚ)
Creators: name: Τσιαγκάλης, Παναγιώτης Αθανασίου
Publisher: name: Aristotle University of Thessaloniki
Year: 2015
Subjects: Ψευδής Βεβαίωση
Υπάλληλος
Έγγραφο
False official certification
State employee
Public document

description: Σκοπός της διπλωματικής εργασίας ήταν η ανάλυση του εγκλήματος της ψευδούς βεβαίωσης, το οποίο τυποποιείται στο άρθρο 242 ΠΚ. Εξετάσαμε επιμέρους έννοιες της αντικειμενικής υπόστασης του ως άνω εγκλήματος, όπως το προστατευόμενο έννομο αγαθό, το υποκείμενο τέλεσης, το δημόσιο έγγραφο, την ίδια την έννοια της βεβαίωσης γεγονότος και τις έννομες συνέπειες. Στη συνέχεια, παρουσιάσαμε την έννοια της κακουργηματικής ψευδούς βεβαίωσης, και ειδικότερα τη σχέση του με το έγκλημα της κακουργηματικής πλαστογραφίας, την έννοια του αθέμιτου οφέλους και το σκοπό οφέλους ή βλάβης. Ασχοληθήκαμε επιπλέον με ζητήματα υποκειμενικής υπόστασης, απόπειρας, συμμετοχής, καθώς και με προβλήματα συρροής, με ιδιαίτερη έμφαση στη σχέση του εγκλήματος της ψευδούς βεβαίωσης με εκείνα της πλαστογραφίας, της απάτης και της υφαρπαγής ψευδούς βεβαίωσης.
description: The aim of the present thesis was the analysis of the criminal offence of false official certification, which is included in the article 242 of the Greek Penal Code. We examined individual features of the actusreus of this criminal offence, such as the legally protected right, the possible subjects, the public document, the certification of a fact and the legal effects. Then we presented the criminal offence of false official certification as a felony charge and especially the connection with the criminal offence of forgery as a felony charge, the concept of the illicit benefit and the aim of benefit or harm. We also examined other matters, such as the mensrea, the attempted false notification, the participation and the afflux with other criminal offences, emphasizing at the connection of the criminal offence of false official certification with the criminal offence of forgery, fraud and fraudulent procurement of false official certification.
TeV gamma-rays from photo-disintegration/de-excitation of cosmic-ray nuclei
Creators: name: Anchordoqui, Luis A.
name: Beacom, John F.
name: Goldberg, Haim
name: Palomares-Ruiz, Sergio
name: Weiler, Thomas J.
Publisher: name: arXiv
Year: 2006
Subjects: subject: Astrophysics (astro-ph)
subject: High Energy Physics - Phenomenology (hep-ph)
subject: Nuclear Theory (nucl-th)
subject: FOS: Physical sciences

description: It is commonly assumed that high-energy gamma-rays are made via either purely electromagnetic processes or the hadronic process of pion production, followed by decay. We investigate astrophysical contexts where a third process (A*) may dominate, namely the photo-disintegration of highly boosted nuclei followed by daughter de-excitation. Starbust regions such as Cygnus OB2 appear to be promising sites for TeV gamma-ray emission via this mechanism. A unique feature of the A* process is a sharp energy minimum ~ 10 TeV/(T/eV) for gamma-ray emission from a thermal region of temperature T. We also check that a diffuse gamma-ray component resulting from the interaction of a possible extreme-energy cosmic-ray nuclei with background radiation is well below the observed EGRET data. The A* mechanism described herein offers an important contribution to gamma-ray astronomy in the era of intense observational activity.
description: To be published in Phys. Rev. Lett
Nonlinear modal analysis of nonconservative systems: Extension of the periodic motion concept
Creators: name: Krack, Malte
Publisher: name: arXiv
Year: 2021
Subjects: subject: Chaotic Dynamics (nlin.CD)
subject: Computational Engineering, Finance, and Science (cs.CE)
subject: FOS: Physical sciences
subject: FOS: Computer and information sciences

description: As the motions of nonconservative autonomous systems are typically not periodic, the definition of nonlinear modes as periodic motions cannot be applied in the classical sense. In this paper, it is proposed 'make the motions periodic' by introducing an additional damping term of appropriate sign and magnitude. It is shown that this generalized definition is particularly suited to reflect the periodic vibration behavior induced by harmonic external forcing or negative linear damping. In a large range, the energy dependence of modal frequency, damping ratio and stability is reproduced well. The limitation to isolated or weakly-damped modes is discussed.
Subject variability in estimates of impact saliency and impact acceptability for wilderness conditions
Creators: name: Rutledge, Ronald Brent
Publisher: name: University of British Columbia
Year: 2009

description: This study examined sources of subject variation in user estimates of impact saliency and the acceptability of impacts on ecological and social conditions found in wilderness. Data collected in a questionnaire sent to visitors to the Spruce Lake Trails Area in British Columbia, Canada were used to test six research hypotheses. The influence of impacts on visitors' wilderness experiences were compared among three sub-groups of the study sample characterized by: 1) how their trip was organized (commercially outfitted vs. privately outfitted); 2) their length of stay (one day vs. two to four days vs. five or more days); and 3) their place of origin (BC residents vs. US residents), respectively. Variations in impact acceptability levels were also compared for the above three sub-groups. The results of hypotheses testing indicated that, overall, the three variables examined (trip organization, length of stay and place of origin) offered little explanation for subject variation in impact saliency and impact acceptability by respondents to the Spruce Lake Trails Area Visitor Study. By and large, survey respondents agreed on the relative influence of most of the impacts evaluated. Behavioral impacts (e.g., discourteous behavior) were judged by all respondents as most important in determining the quality of their wilderness experience. Respondents tended to ignore the social setting (i.e., where the impact occurred) when evaluating the effect of the impacts. Survey respondents had the most difficulty in quantifying an acceptable level of vegetation loss and bare ground at campsites and on or beside trail. They had the least difficulty in quantifying acceptable levels of litter at all locations.
DTRF2020: first results
Creators: name: Seitz, Manuela
name: Bloßfeld, Mathis
name: Glomsda, Matthias
name: Angermann, Detlef
name: Rudenko, Sergei
name: Zeitlhoefler Julian
Publisher: name: Zenodo
Year: 2022

description: The presentation gives an overview over the DTRF2020 combination and its challenges.
Αυτόματη απομόνωση της δομής του ιππόκαμπου, συμπεριλαμβάνοντας τη σκάφη και την παρυφή, από μαγνητικές τομογραφίες ανθρώπινων εγκεφάλων
Creators: name: Σπανός, Γεώργιος Σταύρου
Publisher: name: Aristotle University of Thessaloniki
Year: 2015
Subjects: Αυτόματη απομόνωση/ανίχνευση του ιππόκαμπου
Παρυφή - Σκάφη
Αλληλεπίδραση βάσει της κατανομής έντασης ακμών – Τοπικός Χάρτης Αλληλεπίδρασης (ΤΧΑ)
Automatic segmentation of hippocampus
Fimbria - Alveus
Gradient Distribution Boundary (3GDB)

description: Εξαιτίας της πληθώρας πρωτοκόλλων απομόνωσης της δομής του ιππόκαμπου, οι τεχνικές αυτόματης απομόνωσής του δυσκολεύονται να γενικευτούν ώστε να πληρούν τις προϋποθέσεις για κάθε πρωτόκολλο. Ο κύριος διαχωρισμός των πρωτόκολλων, όσον αφορά τον ιππόκαμπο, είναι η ίδια του η φύση, δηλαδή το κατά πόσον αποτελεί μια ομογενή δομή φαιάς ουσίας ή εάν αποτελείται και από περιοχές λευκής ουσίας. Πιο συγκεκριμένα, πολλά πρωτόκολλα συμπεριλαμβάνουν στη δομή του ιππόκαμπου και τις λεπτές δομές λευκής ουσίας της παρυφής και σκάφης. Η παρούσα διπλωματική εργασία έχει σκοπό να προσπαθήσει να γενικεύσει την υπάρχουσα μέθοδο που βασίζεται στον τοπικό χάρτη συνεισφοράς και αλληλεπίδρασης πολλαπλών ενεργειακών όρων 3GDB , που έχει σχεδιαστεί να ανιχνεύει τον ιππόκαμπο ως ομογενή δομή φαιάς ουσίας. Στόχος της παρούσας διπλωματικής είναι να προσφέρει μια επιπλέον «φάση» στον «τριφασικό» χάρτη 3GDB, που θα αφορά τη συγκεκριμένη αντιμετώπιση της περιοχής της παρυφής και σκάφης βελτιώνοντας έτσι και το συνολικό αποτέλεσμα.
description: Due to oversupply of segmentation protocols in hippocampus, automatic segmentation techniques is difficult to be generalized in order to meet the conditions of every protocol. The main separation of protocols as for hippocampus refers to the nature of its structure because it is not clearly mentioned if hippocampus is a homogeneous gray matter structure or if it constitutes of white matter regions. In particular, many protocols include in hippocampus’ structure the white matter region structures of fimbria and alveus. This thesis aims to generalize an existing method which is based on a local weighting map and interaction between multiple energy terms (3GDB1 - Gradient based Reliability Maps for ACM based Segmentation of Hippocampus). 3GDB was designed so as to detect hippocampus as a homogeneous gray matter structure. The objective of this thesis is to offer an extra phase in the three-phase map of 3GDB in order to segment the challenging deep brain of fimbria and alveus.
A convergent hierarchy of semidefinite programs characterizing the set of quantum correlations
Creators: name: Navascues, Miguel
name: Pironio, Stefano
name: Acin, Antonio
Publisher: name: arXiv
Year: 2008
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: We are interested in the problem of characterizing the correlations that arise when performing local measurements on separate quantum systems. In a previous work [Phys. Rev. Lett. 98, 010401 (2007)], we introduced an infinite hierarchy of conditions necessarily satisfied by any set of quantum correlations. Each of these conditions could be tested using semidefinite programming. We present here new results concerning this hierarchy. We prove in particular that it is complete, in the sense that any set of correlations satisfying every condition in the hierarchy has a quantum representation in terms of commuting measurements. Although our tests are conceived to rule out non-quantum correlations, and can in principle certify that a set of correlations is quantum only in the asymptotic limit where all tests are satisfied, we show that in some cases it is possible to conclude that a given set of correlations is quantum after performing only a finite number of tests. We provide a criterion to detect when such a situation arises, and we explain how to reconstruct the quantum states and measurement operators reproducing the given correlations. Finally, we present several applications of our approach. We use it in particular to bound the quantum violation of various Bell inequalities.
description: 33 pages, 2 figures
Study of autonomous conservative oscillator using an improved perturbation method
Creators: name: Zephania, C. F. Sagar
name: Sil, Tapas
Publisher: name: arXiv
Year: 2020
Subjects: subject: Computational Engineering, Finance, and Science (cs.CE)
subject: FOS: Computer and information sciences

description: In a recent article \cite{manimegalai2019}, Aboodh transform based homotopy perturbation method ($AT$) has been found to produce approximate analytical solutions in a simple way but with better accuracy in comparison to those obtained from some of the established approximation methods \cite{mehdipour2010application,nofal2013analytical} for some physically relevant anharmonic oscillators such as autonomous conservative oscillator (ACO). In the present article, expansion of frequency ($ω$) and an auxiliary parameter ($h$) are incorporated in the framework of the homotopy perturbation method (HPM) to improve the accuracy by retaining its simplicity. Laplace transform is used to make the calculation simpler. This improved HPM ($LH$) is simple but provides highly accurate results for ACO in comparison to those obtained from $AT$. The error in the values of frequency and displacement calculated using the $LH$ is found to be one or two order of magnitude less than those obtained from $AT$ for the considered parameter sets.
description: An improved version is published in JEVT
Διαδικτυακή Ευφυΐα φοιτητών και πτυχιούχων της τριτοβάθμιας εκπαίδευσης
Creators: name: Λιούτα, Ζωή Δημητρίου
Publisher: name: Aristotle University of Thessaloniki
Year: 2015
Subjects: Διαδικτυακή Ευφυΐα
Δειγματοληψία στο διαδίκτυο
Ερωτηματολόγιο μηχανών αναζήτησης
web intelligence
sampling on web
questionnaire through web browsers

description: Σκοπός της παρούσας εργασίας ήταν να κάνουμε μία ομαδική αποτίμηση της διαδικτυακής ευφυΐας φοιτητών και πτυχιούχων της τριτοβάθμιας εκπαίδευσης ηλικίας από 18 έως 35 ετών. Σε ένα δείγμα 117 ατόμων, δίνονται 6 ερωτήσεις που καλούνται να απαντήσουν αναζητώντας την απάντηση στο διαδίκτυο. Για κάθε ερώτηση και κάθε άτομο υπολογίζεται ο χρόνος και ο αριθμός των βημάτων (χτυπημάτων, click) που χρειάστηκε το άτομο ώσπου να φτάσει στη σωστή απάντηση. Έτσι, έχουμε 2 τυχαίες μεταβλητές για την κάθε ερώτηση: τη μεταβλητή Q που μετρά το χρόνο και τη μεταβλητή S που μετρά τον αριθμό των βημάτων. Για κάθε μία από αυτές τις τυχαίες μεταβλητές υπολογίζεται η μέση τιμή, η διασπορά, η τυπική απόκλιση και ο συντελεστής μεταβλητότητας Cv, μέσω του οποίου υπολογίζεται η συνάρτηση πυκνότητας πιθανότητας (σ.π.π.). Τέλος, γίνεται έλεγχος καλής προσαρμογής των θεωρητικών τιμών συχνοτήτων της σ.π.π. που προκύπτει με τις παρατηρούμενες τιμές, με τη χρήση του -test (Chi-square test). Στην κάθε περίπτωση το -test αποδεικνύει καλή προσαρμογή ή μη. Στην παρούσα εργασία η καλή προσαρμογή προέκυψε σε όλες τις περιπτώσεις που μελετήθηκαν.
description: The aim of the present thesis was to collectively evaluate the web intelligence of university undergraduates and postgraduates between 18 and 35 years old. 6 questions are given to a sample of 117 people and they are asked to reply using the internet to find the answer. For every question and every person, the time and number of steps (clicks) required to reach the right answer are measured. Thus, there are 2 random variables for every question: the variable Q which measures the time, and the variable S, which measures the number of steps. For each of these random variables we measure the mean, the dispersion, the standard deviation and the coefficient of variation Cv, with which the probability density function (PDF) is measured. Finally, we check the expected frequency values of PDF with the observed values using the -test (Chi-square test). In every case the -test proves approximately valid.
Η Γνωστική Λειτουργία του Νου και η Επίδρασή της στη Ζωγραφική
Creators: name: Θεοδωρίδου, Λιούμπα Αλέξανδρου
Publisher: name: Aristotle University of Thessaloniki
Year: 2015
Subjects: Γνωστική Διαδικασία
Ζωγραφική
Νους
Cognitive Function
Painting
Brain

description: Στην παρούσα εργασία επισημαίνω τις βασικές συνιστώσες της αντιληπτικής λειτουργίας του ανθρώπου, έτσι όπως αυτές τέθηκαν από την αρχή της φιλοσοφίας έως τη σύγχρονη επιστημονική προσέγγιση και να τις συνδέσω με τη δημιουργική διεργασία της τέχνης, όπως αυτή προσλαμβάνεται και εφαρμόζεται στον κλάδο της ζωγραφικής. Στο πρώτο μέρος της διπλωματικής μου, κάνω μια εισαγωγή στα γενικά στοιχεία της γνωστικής αντίληψης του νου και επισημαίνω τον ουσιαστικό της ρόλο στην επικοινωνία του ανθρώπου με το περιβάλλον. Στο επόμενο κεφάλαιο αναφέρομαι επιλεκτικά με ιστορική σειρά σε ορισμένους από τους φιλοσόφους που ασχολήθηκαν με το γνωσιολογικό πρόβλημα και κατ’ επέκταση γνωστική λειτουργία. Η απόθεση των ερμηνειών τους θα περιοριστεί σε εκείνους που έχουν εισαγάγει σημαντικές θεωρίες καθώς αναφορές αναζήτησης πάνω στο θέμα βρίσκουμε σε ολόκληρη την Ελληνική φιλοσοφία, καθώς και σε μεγάλο εύρος των ξένων φιλοσόφων. Στο τελευταίο μέρος της διπλωματικής εργασίας παραθέτω και αναλύω τα βασικά δομικά στοιχεία της ζωγραφικής, όπως αυτά απορρέουν από τη γνωστική διαδικασία, όπως αντιμετωπίζονται από τη φιλοσοφία και όπως χρησιμοποιούνται από τους καλλιτέχνες, δίνοντας ενδεικτικά παραδείγματα ζωγραφικών έργων.
description: In my thesis I pointed out the basic components of the human perceptional function, as stated from the early philosophical foundations till the modern scientific approach and I connected them with the creative process of art, as perceived and applied in the field of painting. In the first part of my thesis, I am introducing the reader to the basic information of the cognitive perceptional process of the mind and I denote it’s important role in the communication of each person with his environment. In the next chapter, I am presenting in a historical order some of the philosophers that studied the cognitive problem, and as an extent, the cognitive function. At this point, my presentation is limited to the interpretation of the most important theories, since references on this subject can be found throughout the Hellenic philosophy, and later, in a big range of international philosophers. In the last part of my thesis, I am presenting and analyzing the building blocks of the of painting as a creative function and an optical result, just as they are derived from the cognitive process and dealt with by the philosophical approach and in the process as they are used by the artists. Finally I present the most representative examples of paintings that embody all the parameters of the cognitive approach and function of the human brain.
PCPL: Predicate-Correlation Perception Learning for Unbiased Scene Graph Generation
Creators: name: Yan, Shaotian
name: Shen, Chen
name: Jin, Zhongming
name: Huang, Jianqiang
name: Jiang, Rongxin
name: Chen, Yaowu
name: Hua, Xian-Sheng
Publisher: name: arXiv
Year: 2020
Subjects: subject: Computer Vision and Pattern Recognition (cs.CV)
subject: FOS: Computer and information sciences

description: Today, scene graph generation(SGG) task is largely limited in realistic scenarios, mainly due to the extremely long-tailed bias of predicate annotation distribution. Thus, tackling the class imbalance trouble of SGG is critical and challenging. In this paper, we first discover that when predicate labels have strong correlation with each other, prevalent re-balancing strategies(e.g., re-sampling and re-weighting) will give rise to either over-fitting the tail data(e.g., bench sitting on sidewalk rather than on), or still suffering the adverse effect from the original uneven distribution(e.g., aggregating varied parked on/standing on/sitting on into on). We argue the principal reason is that re-balancing strategies are sensitive to the frequencies of predicates yet blind to their relatedness, which may play a more important role to promote the learning of predicate features. Therefore, we propose a novel Predicate-Correlation Perception Learning(PCPL for short) scheme to adaptively seek out appropriate loss weights by directly perceiving and utilizing the correlation among predicate classes. Moreover, our PCPL framework is further equipped with a graph encoder module to better extract context features. Extensive experiments on the benchmark VG150 dataset show that the proposed PCPL performs markedly better on tail classes while well-preserving the performance on head ones, which significantly outperforms previous state-of-the-art methods.
description: To be appeared on ACMMM 2020
Effect of an external electric field on local magnetic moments in silicene
Creators: name: Julian, Villarreal
name: Federico, Escudero
name: Sebastian, Ardenghi Juan
name: Paula, Jasen
Publisher: name: arXiv
Year: 2021
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: In this work we analyze the effects of the application of an external electric field in the formation of a local magnetic moment in silicene. By adding an impurity in a top site in the host lattice and computing the real and imaginary part of the self-energy of the impurity energy level, the polarized density of states is used in order to obtain the occupation number of the up and down spin formation in the impurity considering the mean field approximation. Unequal occupation numbers is the precursor of a formation of a local magnetic moment and this depends critically on the Hubbard parameter, the on-site energy of the impurity, the spin-orbit interaction in silicene and the electric field applied. In particular, it is shown that in the absence of electric field, the boundary between the magnetic and non-magnetic phases increases with the spin-orbit interaction with respect to graphene with a top site impurity and shrinks and narrows it when the electric field is turned on. The electric field effect is studied for negative and positive on-site impurity energies generalizing the results obtained in the literature for graphene.
description: 8 pages
Statistical keyword detection in literary corpora
Creators: name: Herrera, Juan P.
name: Pury, Pedro A.
Publisher: name: arXiv
Year: 2007
Subjects: subject: Computation and Language (cs.CL)
subject: Information Retrieval (cs.IR)
subject: Physics and Society (physics.soc-ph)
subject: FOS: Computer and information sciences
subject: FOS: Physical sciences

description: Understanding the complexity of human language requires an appropriate analysis of the statistical distribution of words in texts. We consider the information retrieval problem of detecting and ranking the relevant words of a text by means of statistical information referring to the "spatial" use of the words. Shannon's entropy of information is used as a tool for automatic keyword extraction. By using The Origin of Species by Charles Darwin as a representative text sample, we show the performance of our detector and compare it with another proposals in the literature. The random shuffled text receives special attention as a tool for calibrating the ranking indices.
description: Published version. 11 pages, 7 figures. SVJour for LaTeX2e
Structural anomalies in brain networks induce dynamical pacemaker effects
Creators: name: Koulierakis, I.
name: Verganelakis, D. A.
name: Omelchenko, I.
name: Zakharova, A.
name: Schoell, E.
name: Provata, A.
Publisher: name: arXiv
Year: 2020
Subjects: subject: Adaptation and Self-Organizing Systems (nlin.AO)
subject: Disordered Systems and Neural Networks (cond-mat.dis-nn)
subject: Pattern Formation and Solitons (nlin.PS)
subject: FOS: Physical sciences

description: Dynamical effects on healthy brains and brains affected by tumor are investigated via numerical simulations. The brains are modeled as multilayer networks consisting of neuronal oscillators, whose connectivities are extracted from Magnetic Resonance Imaging (MRI) data. The numerical results demonstrate that the healthy brain presents chimera-like states where regions with high white matter concentrations in the direction connecting the two hemispheres act as the coherent domain, while the rest of the brain presents incoherent oscillations. To the contrary, in brains with destructed structure traveling waves are produced initiated at the region where the tumor is located. These areas act as the pacemaker of the waves sweeping across the brain. The numerical simulations are performed using two neuronal models: a) the FitzHugh-Nagumo model and b) the Leaky Integrate-and-Fire model. Both models give consistent results regarding the chimera-like oscillations in healthy brains and the pacemaker effect in the tumorous brains. These results are considered as a starting point for further investigation in the detection of tumors with small sizes before becoming discernible on the MRI recordings, as well as in tumor development and evolution.
description: 14 pages, 11 figures
Welsh Wreck Web Research Project (North Cardigan Bay). On-line research into the wreck of the: Lively of Aberystwith
Creators: name: Perks, Graeme
Publisher: name: Archaeology Data Service
Year: 2024

description: Welsh Wreck Web Research Project unpublished report series, 1
description: The Lively was a sloop built at Aberystwyth in 1807, registered there and used as a coaster. The Lively was not listed in Lloyds Register and the owners are unknown. The Lively carried often coal from South Wales to Aberystwyth but also completed voyages to Ireland. Lively was lost near Cardigan in September 1824 during a severe gale, the crew were saved.
Boosted decision trees approach to neck alpha events discrimination in DEAP-3600 experiment
Creators: name: Grobov, Alexey
name: Ilyasov, Aidar
Publisher: name: arXiv
Year: 2020
Subjects: subject: Instrumentation and Detectors (physics.ins-det)
subject: Instrumentation and Methods for Astrophysics (astro-ph.IM)
subject: High Energy Physics - Experiment (hep-ex)
subject: FOS: Physical sciences

description: Machine learning (ML) has been widely applied in high energy physics to help the physical community in particle classification and data analysis. Here we describe the application of machine learning to solve the problem of classifying background and signal events for the DEAP-3600 dark matter search experiment (SNOLAB, Canada). We apply Boosted Decision Trees (BDT) algorithm of ML with improvements from Extra Trees and eXtra Gradient Boosting (XGBoost) methods.
description: 7 pages, 5 figures, 1 table