cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Welsh Wreck Web Research Project (North Cardigan Bay). On-line research into the wreck of the: Ireland of Liverpool
Creators: name: Perks, Graeme
Publisher: name: Archaeology Data Service
Year: 2024

description: Welsh Wreck Web Research Project unpublished report series, 1
description: The Ireland was built as a fully rigged ship in Quebec in 1870 by Julian and Labbee, it was sailed to Liverpool and sold to John Owen of Humphrey Owen and Son. Ireland sailed to Rangoon, returning with a cargo of rice, the cargo shifted in a gale in the English Channel and the crew abandoned her, being taken off by passing vessels. Several attempts were made to salvage the Ireland before the Abersoch Lifeboat and the SS Rebecca towed her into St Tudwal's Roads to anchor. The Ireland is converted to a barque, continuing voyages to India and Burma until a recession when she started sailing to the guano Islands in Peru via Buenos Ayres. The pacific war between Chile and Peru led to her returning to the Far East before voyages to British North America. In 1887 after leaving St John, N B the Ireland encountered thick fog in the Bay of Fundy and ran ashore, becoming a total wreck. A BOT enquiry into Ireland's loss criticised the master but did not suspend his licence.
Keeping a Quantum Bit Alive by Optimized $π$-Pulse Sequences
Creators: name: Uhrig, Götz S.
Publisher: name: arXiv
Year: 2006
Subjects: subject: Quantum Physics (quant-ph)
subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Statistical Mechanics (cond-mat.stat-mech)
subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: A general strategy to maintain the coherence of a quantum bit is proposed. The analytical result is derived rigorously including all memory and back-action effects. It is based on an optimized $π$-pulse sequence for dynamic decoupling extending the Carr-Purcell-Meiboom-Gill (CPMG) cycle. The optimized sequence is very efficient, in particular for strong couplings to the environment.
description: 4 pages, 2 figures; revised version with additional references for better context, more stringent discussion
Synthetically Trained Icon Proposals for Parsing and Summarizing Infographics
Creators: name: Madan, Spandan
name: Bylinskii, Zoya
name: Tancik, Matthew
name: Recasens, Adrià
name: Zhong, Kimberli
name: Alsheikh, Sami
name: Pfister, Hanspeter
name: Oliva, Aude
name: Durand, Fredo
Publisher: name: arXiv
Year: 2018
Subjects: subject: Computer Vision and Pattern Recognition (cs.CV)
subject: FOS: Computer and information sciences

description: Widely used in news, business, and educational media, infographics are handcrafted to effectively communicate messages about complex and often abstract topics including `ways to conserve the environment' and `understanding the financial crisis'. Composed of stylistically and semantically diverse visual and textual elements, infographics pose new challenges for computer vision. While automatic text extraction works well on infographics, computer vision approaches trained on natural images fail to identify the stand-alone visual elements in infographics, or `icons'. To bridge this representation gap, we propose a synthetic data generation strategy: we augment background patches in infographics from our Visually29K dataset with Internet-scraped icons which we use as training data for an icon proposal mechanism. On a test set of 1K annotated infographics, icons are located with 38% precision and 34% recall (the best model trained with natural images achieves 14% precision and 7% recall). Combining our icon proposals with icon classification and text extraction, we present a multi-modal summarization application. Our application takes an infographic as input and automatically produces text tags and visual hashtags that are textually and visually representative of the infographic's topics respectively.
Bi-parameter Potential theory and Carleson measures for the Dirichlet space on the bidisc
Creators: name: Arcozzi, Nicola
name: Mozolyako, Pavel
name: Perfekt, Karl-Mikael
name: Sarfatti, Giulia
Publisher: name: arXiv
Year: 2018
Subjects: subject: Complex Variables (math.CV)
subject: FOS: Mathematics
subject: 31B15, 31C20, 32A07, 46E35

description: We characterize the Carleson measures for the Dirichlet space on the bidisc, hence also its multiplier space. Following Maz'ya and Stegenga, the characterization is given in terms of a capacitary condition. We develop the foundations of a bi-parameter potential theory on the bidisc and prove a Strong Capacitary Inequality. In order to do so, we have to overcome the obstacle that the Maximum Principle fails in the bi-parameter theory.
description: 57 pages, 5 figures, title changed, minor editing
Η Μαγεία στις Βυζαντινές και Μεταβυζαντινές Νομοκανονικές Διαταξεις
Creators: name: Λουκοπούλου, Αθηνά Νικολάου
Publisher: name: Aristotle University of Thessaloniki
Year: 2015
Subjects: Μαγεία
Βυζάντιο
Νομοκανονικές Διατάξεις
Magic
Byzantium
Canonical Provisions

description: Σκοπός της εργασίας ήταν να παρουσιαστεί το φαινόμενο της μαγείας, ένα φαινόμενο που είχε πάρει ανεξέλεγκτες διαστάσεις απο αρχαιοτάτων χρόνων μέχρι και τα μεταβυζαντινά χρόνια. Εξετάσαμε τις αρχές της μαγείας και τα μέσα που αυτή χρησιμοποιεί προκειμένου να επιτευχθεί ο σκοπός της. Εν συνεχεία παρουσιάσαμε αναλυτικά τη δράση της στην αρχαία ελληνική και ρωμαϊκή κοινωνία. Ακόμα αναφερθήκαμε στη μαγεία που επικρατούσε στη βυζαντινή αυτοκρατορία και πως αυτή αντιμετωπίσθηκε τόσο απο τις πολιτειακές διατάξεις του βυζαντινού δικαίου όσο και απο τις κανονικές διατάξεις των Οικουμενικών και Τοπικών Συνόδων αλλά και τις διατάξεις των Πατέρων της Εκκλησίας μας. Και τέλος αναφερθήκαμε σε όλες τις μεταβυζαντινές νομοκανονικές διατάξεις που καταδικάζουν τη μαγεία.
description: The aim of the present thesis was to present the phenomenon of magic, a phenomenon who had uncontrolled dimensions from ancient times through the Byzantine period. We examined the principles of magic and the means it uses to achieve its purpose. Analytically presented then its activity in ancient Greek and Roman society. Even we talked to the magic that prevailed in the Byzantine Empire and how it was viewed both by the provisions of the Byzantine state law and by the normal provisions of the Ecumenical and Local Councils and the provisions of the Fathers of our Church. And finally we talked to all the Byzantine canonical provisions condemning witchcraft.
Άγχος αξιολόγησης και τρόποι αντιμετώπισης ψυχοπιεστικών καταστάσεων από παιδιά ηλικίας 11-12 ετών
Creators: name: Βασιλάκη, Ελένη
name: Βάμβουκας, Μιχάλης Ι.
Publisher: name: Παιδαγωγική Επιθεώρηση
Year: 1997

description: The primary intent of the study was to investigate the relationship between test anxiety and coping strategies employed by school children aged 11-12 years old. For that purpose we used the Test Anxiety Inventory (T.A.I.) by Charles Spielberger (1982), standardised for the Greek population and the Coping strategies Scale (C.S.S.) by Bezevegis (1994). The reliability for the T.A.I was a = 0.80 (Cronbach alpha) and for the C.S.S. was a = 0.76 (Cronbach alpha). The factor analysis of the CCS. scale revealed three fanctional (support from the family, social support, acceptance/offer of help) and four disfunctional coping strategies (isolation, give up, avoidance, transfer to others the finding of solution). At all stages the analysis showed some quite interesting results, which are in accordance with other research evidence. Children who have well-educated parents tend to use their extended social network when faced with problems. In other words, they tend to use functional coping strategies. Children in the 5th grade report high levels in the cognitive subscale of the T.A.I and ask the help of the close and extended social network in order to cope with problems. The only sex difference appeared is related to the coping strategy transfer to others the finding of solution. More precisely, males tend to use more often than the females this strategy. The first child in the family seeks support from the extended social network and the last one prefers to isolate himself from the problem. The more children in the family the more often they use the strategy isolation. We, also, examined the relationship between anxiety and coping strategies. The analysis showed that the last child of the family experiences high Levels of anxiety. When the children are anxious they ask their parents help. The higher the mother's educational level, the higher the anxiety level of the children in the family. Perhaps the performance of multiple and some times conflicting roles raises mother's educational level which is transfered to the children.
description: Παιδαγωγική Επιθεώρηση, Vol. 25 (1997)
Υλοποίηση αλγορίθμου εύρεσης βέλτιστης διαδρομής κινούμενης μονάδας
Creators: name: Κριτοπούλου, Παρασκευή Φωτίου
Publisher: name: Aristotle University of Thessaloniki
Year: 2015
Subjects: Αλγόριθμος Α*
Βέλτιστη Διαδρομή
Κινούμενη Μονάδα
Α* Algorithm
Path Finder
Moving Unit

description: Η παρούσα εργασία πραγματεύεται την ανάπτυξη ενός αλγορίθμου ικανού να εντοπίζει τη βέλτιστη διαδρομή κατά μήκος μίας αδιερεύνητης περιοχής, η οποία εκτείνεται από μια αρχική θέση, την αφετηρία, έως κάποιο στόχο, παρακάμπτοντας όποια εμπόδια μπορεί να υπάρχουν στο ενδιάμεσο διάστημα. Σκοπός του αλγορίθμου είναι η εφαρμογή σε ρομποτικό όχημα. Το πρόγραμμα αποτελείται κυρίως από το χάρτη, τον Αλγόριθμο Αναζήτησης και τη μέθοδο διασύνδεσης του αλγορίθμου με την κινούμενη μονάδα. Υλοποιείται σε C++ και επιτρέπει τη διαμόρφωση της περιοχής κίνησης. Η επαλήθευση και μελέτη της λειτουργίας του αλγορίθμου, γίνεται μέσω ποικίλων προσομοιώσεων. Κατέστη δυνατός o επιτυχής σχεδιασμός βέλτιστων διαδρομών σε στατικό αλλά άγνωστο περιβάλλον με τη βοήθεια του αλγορίθμου Α*.
description: This project documents the development of an algorithm, capable of sensing the best path extended from a beginning to an end, bypassing any existing obstacles while being placed at an unexplored area. The algorithm aims to be implemented to a robotic vehicle. The program application is consisted of a map, the Searching Algorithm and the interface between the algorithm and the moving unit. It is being implemented on C++ and has the ability to configure the search area. The study and verification of the algorithm is achieved through various simulations. There was a degree of success on finding the best paths on a static, yet unexplored environment, through the A* algorithm implementation.
From Cells to Islands: An unified Model of Cellular Parallel Genetic Algorithms
Creators: name: Simoncini, David
name: Collard, Philippe
name: Verel, Sébastien
name: Clergue, Manuel
Publisher: name: arXiv
Year: 2008
Subjects: subject: Neural and Evolutionary Computing (cs.NE)
subject: FOS: Computer and information sciences

description: This paper presents the Anisotropic selection scheme for cellular Genetic Algorithms (cGA). This new scheme allows to enhance diversity and to control the selective pressure which are two important issues in Genetic Algorithms, especially when trying to solve difficult optimization problems. Varying the anisotropic degree of selection allows swapping from a cellular to an island model of parallel genetic algorithm. Measures of performances and diversity have been performed on one well-known problem: the Quadratic Assignment Problem which is known to be difficult to optimize. Experiences show that, tuning the anisotropic degree, we can find the accurate trade-off between cGA and island models to optimize performances of parallel evolutionary algorithms. This trade-off can be interpreted as the suitable degree of migration among subpopulations in a parallel Genetic Algorithm.
On the singularity structure of Kahan discretizations of a class of quadratic vector fields
Creators: name: Zander, René
Publisher: name: arXiv
Year: 2020
Subjects: subject: Exactly Solvable and Integrable Systems (nlin.SI)
subject: Mathematical Physics (math-ph)
subject: FOS: Physical sciences

description: We discuss the singularity structure of Kahan discretizations of a class of quadratric vector fields and provide a classification of the parameter values such that the corresponding Kahan map is integrable, in particular, admits an invariant pencil of elliptic curves.
description: 19 pages, 4 figures, some minor changes
Hot Stars With Kepler Planets Have High Obliquities
Creators: name: Louden, Emma M.
name: Winn, Joshua N.
name: Petigura, Erik A.
name: Isaacson, Howard
name: Howard, Andrew W.
name: Masuda, Kento
name: Albrecht, Simon
name: Kosiarek, Molly R.
Publisher: name: arXiv
Year: 2020
Subjects: subject: Earth and Planetary Astrophysics (astro-ph.EP)
subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: It has been known for a decade that hot stars with hot Jupiters tend to have high obliquities. Less is known about the degree of spin-orbit alignment for hot stars with other kinds of planets. Here, we re-assess the obliquities of hot Kepler stars with transiting planets smaller than Neptune, based on spectroscopic measurements of their projected rotation velocities (vsini). The basis of the method is that a lower obliquity -- all other things being equal -- causes sini to be closer to unity and increases the value of vsini. We sought evidence for this effect using a sample of 150 Kepler stars with effective temperatures between 5950 and 6550K and a control sample of 101 stars with matching spectroscopic properties and random orientations. The planet hosts have systematically higher values of vsini than the control stars, but not by enough to be compatible with perfect spin-orbit alignment. The mean value of sini is 0.856 +/- 0.036, which is 4-sigma away from unity (perfect alignment), and 2-sigma away from pi/4 (random orientations). There is also evidence that the hottest stars have a broader obliquity distribution: when modeled separately, the stars cooler than 6250K have = 0.928 +/- 0.042, while the hotter stars are consistent with random orientations. This is similar to the pattern previously noted for stars with hot Jupiters. Based on these results, obliquity excitation for early-G and late-F stars appears to be a general outcome of star and planet formation, rather than being exclusively linked to hot Jupiter formation.
description: AJ, in press [15 pages]
Καταγραφή αναπαραστάσεων και απόψεων ως προς τη διαχείριση της δυσλεξίας στο σχολικό περιβάλλον, και ειδικότερα στο ξενόγλωσσο μάθημα
Creators: name: Τσούλη, Ευθαλία Ιωάννη
Publisher: name: Aristotle University of Thessaloniki
Year: 2015
Subjects: Κοινωνικές αναπαραστάσεις δυσλεξίας
Δυσλεξία και ξένες γλώσσες
Dyslexia social representations
Dyslexia and foreing languages

description: Σκοπός της παρούσας έρευνας ήταν η μελέτη των αναπαραστάσεων και των απόψεων που έχουν υιοθετηθεί από τον κοινωνικό περίγυρο, σχετικά με τη δυσλεξία και τους μαθητές με δυσλεξία. Εξετάστηκε σε ποιο βαθμό οι αναπαραστάσεις της δυσλεξίας και του μαθητή με δυσλεξία, μπορούν να έχουν αντίκτυπο στις συμπεριφορές των εκπαιδευτικών, των γονέων και των μαθητών, καθώς επίσης και στις διδακτικές και παιδαγωγικές πρακτικές στο σχολείο και στο σπίτι. Αναζητήθηκαν οι παράγοντες που θα μπορούσαν να επηρεάζουν περισσότερο τις αναπαραστάσεις και την εικόνα των γονέων, των εκπαιδευτικών και των συμμαθητών απέναντι στο μαθητή με δυσλεξία. Τέλος, με τη βοήθεια της στατιστικής ανάλυσης, καταγράψαμε και ερμηνεύσαμε τις αντιλήψεις που επικρατούν σήμερα γύρω από τη δυσλεξία, τόσο στο οικογενειακό όσο και στο σχολικό περιβάλλον της αστικής και της επαρχιακής ζωής.
description: The purpose of this research was to study the representations and the opinions adopted by the social environment on dyslexia and students with dyslexia. We examined if the representations of dyslexia and dyslexic student can have an impact on the attitudes of teachers, parents and students, as well as the teaching and pedagogical practices at school and at home. After that, we searched about the factors that could most affect the representations and the views of parents, teachers, and students towards the dyslexic student. Finally, the statistical analysis helped us to record and interpret the perceptions that currently prevail towards dyslexia, both in the family and in schools of urban and provincial life.
RASS-SDSS Galaxy Cluster Survey. V. The X-ray-Underluminous Abell Clusters
Creators: name: Popesso, P.
name: Biviano, A.
name: Böhringer, H.
name: Romaniello, M.
Publisher: name: arXiv
Year: 2006
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: In this paper we consider a large sample of optically selected clusters, in order to elucidate the physical reasons for the existence of X-ray underluminous clusters. For this purpose we analyze the correlations of the X-ray and optical properties of a sample of 137 spectroscopically confirmed Abell clusters in the SDSS database. We search for the X-ray counterpart of each cluster in the ROSAT All Sky Survey. We find that 40% of our clusters have a marginal X-ray detection or remain undetected in X-rays. These clusters appear too X-ray faint on average for their velocity dispersion determined mass, i.e. they do not follow the scaling relation between X-ray luminosity and virial mass traced by the other clusters. On the other hand, they do follow the general scaling relation between optical luminosity and virial mass. We refer to these clusters as the X-ray-Underluminous Abell clusters (AXU clusters, for short) and designate as 'normal' the X-ray detected Abell systems. We examine the distributions and properties of the galaxy populations of the normal and the AXU clusters, separately. The AXU clusters are characterized by leptokurtic (more centrally concentrated than a Gaussian) velocity distribution of their member galaxies in the outskirts ($1.5 < r/r_{200} \leq 3.5$), as expected for the systems in accretion. In addition, the AXU clusters have a higher fraction of blue galaxies in the external region and show a marginally significant paucity of galaxies at the center. Our results seem to support the interpretation that the AXU clusters are systems in formation undergoing a phase of mass accretion. Their low X-ray luminosity should be due to the still accreting Intracluster gas or to an ongoing merging process.
description: 19 pages, 11 figures, A&A in press
Γνωστική ανάπτυξη μαθητών Λυκείου: Θεωρητικές και εκπαιδευτικές επιπτώσεις
Creators: name: Βαλανίδης, Νίκος
Publisher: name: Παιδαγωγική Επιθεώρηση
Year: 1997

description: The study investigated the structure and development of formal thought among tenth-, eleventh-, and twelfth-grade students. The subjects of the study (708 boys and 844 girls) were the total number of students from 60 intact classes attending the science, the economic, and the other sections of the upper cycle of two secondary schools in a town of Cyprus. Students' performance on a standardized Test of Logical Thinking (TOLT) was used as a measure of their cognitive abilities related to control of variables, proportional, probabilistic, correlation and combinatorial reasoning and as a means of categorizing them into stages of cognitive development based on Piagetian theory. The observed statistical differences in students' performance on TOLT items related to gender, section of study, or grade (chronological age) did not correspond tο observed differences concerning students' academic achievement in school subjects. Regression analysis showed, however, that section of study, achievement in mathematics, gender, achievement in English language, and grade (chronological age), but not achievement in Greek language and grade point average, contributed significantly to the prediction of students' performance on TOLT explaining more than 41% of the total variance. Factor analysis of performance on the ten TOLT items {two items from each reasoning mode) produced a three-factor solution for the sample of girls and a two-factor solution for the sample of boys explaining 51.7% and 58.2% of the total variance, respectively. There were also significant differences of students' performance between items related to the same or different reasoning modes. The results of the study do not corroborate with basic aspects of the Piagetian paradigm of cognitive development and indicate that different theoretical perspectives should be considered when evaluating cognitive development. The results of the study indicate, furthermore, that the existing curricula and the traditional teaching practices are incompatible with students' capacity in terms of cognitive development. Research related to the nature and the process of cognitive development should be intensified and new curricula, "interventionary" in nature, based on research evidence need to be designed and implemented to facilitate optimal cognitive growth.
description: Παιδαγωγική Επιθεώρηση, Vol. 25 (1997)
Radiometric correction in range-SPECAN SAR processing
Creators: name: Hobooti, Haleh
Publisher: name: University of British Columbia
Year: 2009

description: This thesis investigates the reasons for, and proposes correction methods to reduce the scalloping inherent in the range dimension in images processed using the SPECAN SAR processing algorithm. These corrections methods are successfully tested using ERS-1 satellite data. The SPECAN algorithm was developed in 1979 by MacDonald Dettwiler and Associates, as a multilook version of the deramp/FFT method of pulse compression. The algorithm provides an efficient method of producing spaceborne SAR imagery of modest resolution, which makes it ideal for quicklook imaging. Widespread use of the algorithm in quicklook imaging, however, is hindered by the scalloping present in both the range and azimuth dimensions of the image. This thesis concentrates on correction of range scalloping by presenting explanations for the two types of scalloping present in the range dimension of SPECAN processed images. The basic scalloping present in all scenes is due to the time variation in the envelope of the transmitted signal. The extra scalloping seen in some scenes is due to clipping of the ERS-1 raw data. Because of the geometry of the SPECAN processing cycles, the radiometry of the output is sensitive to the transmitted chirp amplitude. The 0.5 dB power difference between the beginning and end of the transmitted chirp is reflected in each compressed output segment, creating a periodic lightening and darkening throughout the image. This banding effect is especially noticeable in low contrast scenes. This problem is corrected using the chirp replica which is embedded in the data header as an estimate of the pulse shape. The extra scalloping observed in some high reflectivity scenes is attributed to the clipping of the ERS-1 raw data in these scenes. Clipping causes attenuation in the output power. This power loss varies along range according to the degree of saturation, and is different for each compressed data block, thereby creating a discontinuity between adjacent compressed segments which adds to (or subtracts from) the basic scalloping effect. This problem is corrected using the relationship between power loss and degree of saturation in the Gaussian distributed raw data.
Self-dual Maps I : antipodality
Creators: name: Montejano, Luis
name: Alfonsín, Jorge L. Ramírez
name: Rasskin, Ivan
Publisher: name: arXiv
Year: 2020
Subjects: subject: Combinatorics (math.CO)
subject: FOS: Mathematics

description: A self-dual map $G$ is said to be \emph{antipodally self-dual} if the dual map $G^*$ is antipodal embedded in $\mathbb{S}^2$ with respect to $G$. In this paper, we investigate necessary and/or sufficient conditions for a map to be antipodally self-dual. In particular, we present a combinatorial characterization for map $G$ to be antipodally self-dual in terms of certain \emph{involutive labelings}. The latter lead us to obtain necessary conditions for a map to be \emph{strongly involutive} (a notion relevant for its connection with convex geometric problems). We also investigate the relation of antipodally self-dual maps and the notion of \emph{ antipodally symmetric} maps. It turns out that the latter is a very helpful tool to study questions concerning the \emph{symmetry} as well as the \emph{amphicheirality} of \emph{links}.
AstroSat observations of eclipsing high mass X-ray binary pulsar OAO 1657-415
Creators: name: Jaisawal, Gaurava K.
name: Naik, Sachindra
name: Epili, Prahlad R.
name: Chhotaray, Birendra
name: Jana, Arghajit
name: Agrawal, P. C.
Publisher: name: arXiv
Year: 2021
Subjects: subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: We present the results obtained from analysis of two AstroSat observations of the high mass X-ray binary pulsar OAO 1657-415. The observations covered 0.681-0.818 and 0.808-0.968 phases of the $\sim$10.4 day orbital period of the system, in March and July 2019, respectively. Despite being outside the eclipsing regime, the power density spectrum from the first observation lacks any signature of pulsation or quasi-periodic oscillations. However, during July observation, X-ray pulsations at a period of 37.0375 s were clearly detected in the light curves. The pulse profiles from the second observation consist of a broad single peak with a dip-like structure in the middle across the observed energy range. We explored evolution of the pulse profile in narrow time and energy segments. We detected pulsations in the light curves obtained from 0.808--0.92 orbital phase range, which is absent in the remaining part of the observation. The spectrum of OAO 1657-415 can be described by an absorbed power-law model along with an iron fluorescent emission line and a blackbody component for out-of-eclipse phase of the observation. Our findings are discussed in the frame of stellar wind accretion and accretion wake at late orbital phases of the binary.
description: 11 pages, 8 figures and 2 tables; Accepted for publication in the Journal of Astrophysics & Astronomy
Ball packings for links
Creators: name: Alfonsín, Jorge Luis Ramírez
name: Rasskin, Ivan
Publisher: name: arXiv
Year: 2020
Subjects: subject: Combinatorics (math.CO)
subject: Geometric Topology (math.GT)
subject: FOS: Mathematics
subject: 52C17, 57K10

description: The ball number of a link $L$, denoted by $ball(L)$, is the minimum number of solid balls (not necessarily of the same size) needed to realize a necklace representing $L$. In this paper, we show that $ball(L)\leq 5 cr(L)$ where $cr(L)$ denotes the crossing number of $L$. To this end, we use Lorentz geometry applied to ball packings. The well-known Koebe-Andreev-Thurston circle packing Theorem is also an important brick for the proof. Our approach yields to an algorithm to construct explicitly the desired necklace representation of $L$ in the 3-dimensional space.
Strong interlayer coupling in two-dimensional PbSe with high thermoelectric performance
Creators: name: Yin, Z. P.
name: Sheng, C. Y.
name: Hu, R.
name: Han, S. H.
name: Fan, D. D.
name: Cao, G. H.
name: Liu, H. J.
Publisher: name: arXiv
Year: 2020
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: It was generally assumed that weak van der Waals interactions exist between neighboring layers in the two-dimensional group-IV chalcogenides. Using PbSe as a prototypal example, however, we find additional strong coupling between the Pb-Pb layers, as evidenced by detailed analysis of the differential charge density. The coupling resembles covalent-like bond and exhibits strong harmonicity around the equilibrium distance, which can be fine tuned to obviously reduce the phonon thermal conductivity but slightly change the electronic transport of PbSe. As a consequence, a maximum ZT value of 2.5 can be realized at 900 K for the p-type system. Our work offers an effective and feasible design strategy to enhance the thermoelectric performance of similar layered structures.
Οι αντιλήψεις των Κύπριων δασκάλων για την αξιολόγηση των επιτευγμάτων των μαθητών
Creators: name: Κυριακίδης, Λεωνίδας
Publisher: name: Παιδαγωγική Επιθεώρηση
Year: 1996

description: This paper reports and analyses finding from an investigation into Cypriot teachers' perceptions of national policy for assessment reform in primary schools. Questionnaires were sent to a representative sample of Cypriot teachers randomly selected (n=340) from the total population. A response rate of 70% was obtained and statistical analysis was carried out by SPSS. Interviews with 20 teachers who replied to the questionnaire were also conducted in order to measure the validity of the research. There were seven main findings. First, formative purposes of assessment were accorded most, and summative purposes least, importance. Second, a correlation between teachers' perceptions of purposes of assessment and purposes of record keeping was identified. Third, teachers conceptualized assessment as natural part of teaching but paradoxically favored more formally structured techniques of assessment. Fourth, they considered record keeping as an essential part of assessment and as a means to achieve formative purposes. Fifth, they believed that assessment should not refer only to pupils' knowledge but also to pupils' skills and attitudes. They considered pupils' abilities to apply their knowledge in unfamiliar situations and pupils' attitudes to the several subjects as important objectives for teachers' assessment. Sixth, they did not believe that there should be a common record, or that pupils' achievement in each subject should be defined only by an overall grade. Finally, they considered further training in techniques of assessment and better working conditions as more important ways of improving assessment than the development of the national and school policy hi assessment. Finally, implications for the implementation of assessment policy are discussed.
description: Παιδαγωγική Επιθεώρηση, Vol. 24 (1996)
Benchmarking the ab initio hydrogen equations of state for the interior structure of Jupiter
Creators: name: Mazevet, S.
name: Licari, A.
name: Soubiran, F.
Publisher: name: arXiv
Year: 2020
Subjects: subject: Earth and Planetary Astrophysics (astro-ph.EP)
subject: FOS: Physical sciences

description: As Juno is presently measuring Jupiter's gravitational moments to unprecedented accuracy, models for the interior structure of the planet are putted to the test. While equations of state based on first principles or ab initio simulations have been available and used for the two most abundant elements constituting the envelope, hydrogen and helium, significant discrepancies remain regarding the predictions of the inner structure of Jupiter. The differences are severe enough to clutter the analysis of Juno's data and even cast doubts on the usefulness of these computationally expensive EOSs for the modeling of the interior of Jupiter and exoplanets at large. Using our newly developed equations of state for hydrogen and helium, we asses the ab initio equations of state currently available and establish their efficiency at predicting the interior structure of Jupiter in a two-layers model. By adjusting our free energy parameterization to reproduce previous ab initio EOS behavior, we identify the source of the disagreement previously reported for the interior structure of Jupiter. We further point to area where care should be taken when building EOS for the modeling of giant planets. This concerns the interpolation between the ab initio results and the physical models used to cover the low density range as well as the interpolation of the {\sl ab initio} simulation results at high densities. This sensitivity falls well within the uncertainties of the ab initio simulations. This suggests that hydrogen EOS should be carefully benchmarked using a simple planetary model before being used in the more advanced planetary models needed to interpret the Juno data. We finally provide an updated version of our ab initio hydrogen EOS recently published.
Συγκριτική μελέτη των αντιλήψεων 4ετών φοιτητών του ΠΤΔΕ και μαθητών Ε' και ΣΤ' τάξης του δημοτικού σχετικά με την έννοια της άνωσης στα υγρά
Creators: name: Καρανίκας, Γ.
name: Κόκκοτας, Παναγιώτης Β.
name: Καριώτογλου, Πέτρος Π.
Publisher: name: Παιδαγωγική Επιθεώρηση
Year: 1996

description: Our research aimed to compare the ideas of Primary School children aged 10-12 y. to those of 4th year students of School of Primary Education of Athens University about the buoyancy in liquids. For the elicitation and recording of these ideas a written questionnaire was used, a few months after the topic was taught to them. The findings indicated that the majority of pupils and a great number of students ignore the factors that affect the buoyancy. They claim that buoyancy depends on the shape, the weight, the surface, etc., of the dipped body, or on the total volume of the liquid where the body is submerged. It was ascertained that the taught subject had a short term effect in their way of thinking. There were also indications that support the correlation between the low achievement and the social environment of the pupils. These findings, in accordance with those in other topic areas, call for revaluation of teaching approaches in teaching in science.
description: Παιδαγωγική Επιθεώρηση, Vol. 24 (1996)
ARMADA I: Triple Companions Detected in B-Type Binaries alpha Del and nu Gem
Creators: name: Gardner, Tyler
name: Monnier, John D.
name: Fekel, Francis C.
name: Schaefer, Gail
name: Johnson, Keith J. C.
name: Bouquin, Jean-Baptiste Le
name: Kraus, Stefan
name: Anugu, Narsireddy
name: Setterholm, Benjamin R.
name: Labdon, Aaron
name: Davies, Claire L.
name: Lanthermann, Cyprien
name: Ennis, Jacob
name: Ireland, Michael
name: Kratter, Kaitlin M.
name: Brummelaar, Theo Ten
name: Sturmann, Judit
name: Sturmann, Laszlo
name: Farrington, Chris
name: Gies, Douglas R.
name: Klement, Robert
name: Adams, Fred C.
Publisher: name: arXiv
Year: 2020
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: Ground-based optical long-baseline interferometry has the power to measure the orbits of close binary systems at ~10 micro-arcsecond precision. This precision makes it possible to detect "wobbles" in the binary motion due to the gravitational pull from additional short period companions. We started the ARrangement for Micro-Arcsecond Differential Astrometry (ARMADA) survey with the MIRC-X instrument at the CHARA array for the purpose of detecting giant planets and stellar companions orbiting individual stars in binary systems. We describe our observations for the survey, and introduce the wavelength calibration scheme that delivers precision at the tens of micro-arcseconds level for <0.2 arcsecond binaries. We test our instrument performance on a known triple system kappa Peg, and show that our survey is delivering a factor of 10 better precision than previous similar surveys. We present astrometric detections of tertiary components to two B-type binaries: a 30-day companion to alpha Del, and a 50-day companion to nu Gem. We also collected radial velocity data for alpha Del with the Tennessee State University Automated Spectroscopic Telescope at Fairborn Observatory. We are able to measure the orbits and masses of all three components in these systems. We find that the previously published RV orbit for the inner pair of nu Gem is not consistent with our visual orbit. The precision achieved for these orbits suggests that our ARMADA survey will be successful at discovering new compact triple systems to A/B-type binary systems, leading to better statistics of hierarchical system architectures and formation history.
description: 25 pages, 15 figures, accepted for publication in AJ
Logarithmic delocalization of end spins in the S=3/2 antiferromagnetic Heisenberg chain
Creators: name: Fath, Gabor
name: Legeza, Ors
name: Lajko, Peter
name: Igloi, Ferenc
Publisher: name: arXiv
Year: 2006
Subjects: subject: Statistical Mechanics (cond-mat.stat-mech)
subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: Using the DMRG method we calculate the surface spin correlation function, $C_L(l)=< S_l^z S_{L+1-l}^z>$, in the spin $S=3/2$ antiferromagnetic Heisenberg chain. For comparison we also investigate the $S=1/2$ chain with S=1 impurity end spins and the S=1 chain. In the half-integer spin models the end-to-end correlations are found to decay to zero logarithmically, $C_L(1)\sim (\log L)^{-2d}$, with $d=0.13(2)$. We find no surface order, in clear contrast with the behavior of the S=1 chain, where exponentially localized end spins induce finite surface correlations. The lack of surface order implies that end spins do not exist in the strict sense. However, the system possesses a logarithmically weakly delocalizing boundary excitation, which, for any chain lengths attainable numerically or even experimentally, creates the illusion of an end spin. This mode is responsible for the first gap, which vanishes asymptotically as $Δ_1 \approx (πv_S d)/(L\ln L)$, where $v_S$ is the sound velocity and $d$ is the logarithmic decay exponent. For the half-integer spin models our results on the surface correlations and on the first gap support universality. Those for the second gap are less conclusive, due to strong higher-order corrections.
description: 10 pages, 8 figures
A device to localize sound sources
Creators: name: Harris, Carol Patricia
Publisher: name: University of British Columbia
Year: 2009

description: This thesis contains a detailed report of the design, construction and testing of the prototype of a new assistive listening device. The project objective was to design a device that would use a sound localizing algorithm based on human auditory function to determine the position of a target sound source, and would then automatically steer a highly directional microphone to that position. Preferentially amplifying only the intended sound source provides a much cleaner signal for the user, and improves speech intelligibility. Such a device would be useful in controlled environments such as in the classroom, at a business meeting, or situation where there was orderly conversation with only one speaker at a time. The completed device consists of an array of three omnidirectional microphones, a small directional microphone mounted on a motorized rotating platform, and a digital signal processing (DSP) board. Sound samples collected from the omnidirectional microphones are stored on the DSP board, and are analyzed to determine the position of any sound sources present. If a source is identified, the directional microphone is steered to point in the direction of the source. The directional microphone has a range of travel of 240 degrees, through which it can rotate in under one second, and settle on the chosen location with an error of less than five degrees. The performance of the device as a whole was tested in an anechoic environment. Results showed that the device could localize voice, sinusoidal, and pulsed signals with average errors over a variety of test configurations ranging from approximately three to six degrees.
Investigation of the 19Na via resonance elastic scattering
Creators: name: Skorodumov, B. B.
name: Rogachev, G. V.
name: Boutachkov, P.
name: Aprahamian, A.
name: Kolata, J. J.
name: Lamm, L. O.
name: Quinn, M.
name: Woehr, A.
Publisher: name: arXiv
Year: 2006
Subjects: subject: Nuclear Experiment (nucl-ex)
subject: FOS: Physical sciences

description: The structure of the unbound proton-rich isotope 19Na was studied in resonance elastic scattering of a radioactive 18Ne beam on a proton target using the thick-target inverse-kinematics method. The experiment covered excitation energy range from 0.5 to 2.7 MeV in c.m.s. Only one state of 19Na (the second excited state) was observed. A combined R-matrix and potential-model analysis was performed. The spin and parity assignment of this second excited state was confirmed to be 1/2+. We showthat the position of the 1/2+ state significantly affects the reaction rate through that state but the total reaction rate remains unchanged since the 18Ne(2p,gamma) proceeds mostly via the ground and first excited states in 19Na at stellar temperatures.
description: 13 pages, 5 figures
Διακρίσεις με βάση το φύλο στον τομέα της υγείας και βλαπτικές πρακτικές ιατρικού χαρακτήρα
Creators: name: Καλαϊτζή, Αναστασία Θωμά
Publisher: name: Aristotle University of Thessaloniki
Year: 2015
Subjects: Βλαπτικές πρακτικές
Διάκριση
Υγεία
Harmful practices
Discrimination
Health

description: Η παρούσα διπλωματική εργασία έχει σκοπό να επισημάνει τις διακρίσεις που υφίστανται στον χώρο της υγείας οι γυναίκες και την πραγματική ανισότητα που βιώνουν λόγω εθιμικών βλαπτικών πρακτικών. Η ισότητα των φύλων συνιστά θεμελιώδες δικαίωμα για όλους και όλες καθώς και στοιχειώδη αξία για κάθε δημοκρατία. Προκειμένου να διασφαλιστεί αυτό το δικαίωμα, δεν απαιτείται μόνο η νομική αναγνώρισή του, αλλά και η εφαρμογή του σε όλους τους τομείς της ζωής και κυρίως της υγείας. Για να εξαλειφθούν οι διακρίσεις στον τομέα της υγείας, θα πρέπει οι γυναίκες να αποκτήσουν ίση πρόσβαση στις υπηρεσίες παροχής υγείας και μέσω της χειραφέτησής τους να απολαύσουν ίσα δικαιώματα και καλύτερες ιατροφαρμακευτικές παροχές. Η κάθε κοινωνία ξεχωριστά αλλά και σε συλλογικό πλαίσιο, τοπικά ή περιφερειακά, θα πρέπει να ληφθούν μέτρα και δράσεις υπέρ των γυναικών. Οι εθιμικές βλαπτικές πρακτικές, είναι απόρροια θρησκευτικών και πολιτιστικών πεποιθήσεων. θα πρέπει επομένως να εξαλειφθούν και οι δράστες των πρακτικών αυτών να τιμωρούνται. Οι άντρες και τα αρσενικά τέκνα θα πρέπει βοηθήσουν στην απαλοιφή των στερεοτύπων και των προτύπων ρόλων ώστε να αποκατασταθεί η ισότητα στις οικογένειες και στις κοινωνίες αντίστοιχα, αλλά και μέσω τις εκπαίδευσης και της μόρφωσης των γυναικών. Τέλος, όλες οι παραπάνω πρακτικές συνιστούν σοβαρές παραβιάσεις των ανθρωπίνων δικαιωμάτων των γυναικών και των νεαρών κοριτσιών και αποτελούν εμπόδιο στην επίτευξη ισότητας μεταξύ γυναικών και ανδρών.
description: This thesis aims to highlight existing discrimination between women in the health sector, and actual inequality experienced by these harmful customary practices. Gender equality is a fundamental right for all and an essential value for every democracy. To ensure this right, it needs not only to be legally recognized, but its application in all areas of life and especially health. To eliminate discrimination in the health sector, women should gain equal access to health services and through their emancipation to enjoy equal rights and better healthcare benefits. Each society individually and collectively, local or regional, should take measures and actions in favor of women. The customary harmful practices are the result of religious and cultural beliefs. They should therefore be eliminated and the perpetrators of such practices punishable. The men and male children should help eliminate stereotypes and role models in order to restore equality in the families and societies and through education and literacy too. Finally, all these practices constitute serious violations of human rights of women and girls and are an obstacle to achieve equality between women and men.
Recent Achievements on the development of the Herschel/PACS Bolometer arrays
Creators: name: Billot, N.
name: Agnese, P.
name: Boulade, O.
name: Cigna, C.
name: Doumeyrou, E.
name: Horeau, B.
name: Lepennec, J.
name: Martignac, J.
name: Pornin, J. -L.
name: Reveret, V.
name: Rodriguez, L.
name: Sauvage, M.
name: Simoens, F.
name: Vigroux, L.
Publisher: name: arXiv
Year: 2006
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: A new type of bolometer arrays sensitive in the Far Infrared and Submillimeter range has been developped and manufactured by CEA/LETI/SLIR and will be integrated in the PACS instrument onboard the Herschel Space Observatory (launch date 2008). The main innovations are their collective manufacturing technique (production of 3-side buttable 16x16 arrays) and their high mapping efficiency (large format detector and instantaneous Nyquist sampling). Their measured NEP is 2x10^-16 W/Hz^-0.5 and their thermometric passband about 4-5 Hz. In this paper we describe CEA bolometers and present the results obtained during the last test campaign.
description: Proccedings of the 'Beaune 2005: New Developement In Photodetection International Conference' submitted to NIM section A
Feature Space Exploration For Planning Initial Benthic AUV Surveys
Creators: name: Shields, Jackson
name: Pizarro, Oscar
name: Williams, Stefan B.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Robotics (cs.RO)
subject: Machine Learning (cs.LG)
subject: FOS: Computer and information sciences

description: Special-purpose Autonomous Underwater Vehicles (AUVs) are utilised for benthic (seafloor) surveys, where the vehicle collects optical imagery of the seafloor. Due to the small-sensor footprint of the cameras and the vast areas to be surveyed, these AUVs can not feasibly collect full coverage imagery of areas larger than a few tens of thousands of square meters. Therefore it is necessary for AUV paths to sample the surveys areas sparsely, yet effectively. Broad-scale acoustic bathymetric data is readily available over large areas, and is often a useful prior of seafloor cover. As such, prior bathymetry can be used to guide AUV data collection. This research proposes methods for planning initial AUV surveys that efficiently explore a feature space representation of the bathymetry, in order to sample from a diverse set of bathymetric terrain. This will enable the AUV to visit areas that likely contain unique habitats and are representative of the entire survey site. We propose several information gathering planners that utilise a feature space exploration reward, to plan freeform paths or to optimise the placement of a survey template. The suitability of these methods to plan AUV surveys is evaluated based on the coverage of the feature space and also the ability to visit all classes of benthic habitat on the initial dive. Informative planners based on Rapidly-expanding Random Trees (RRT) and Monte-Carlo Tree Search (MCTS) were found to be the most effective. This is a valuable tool for AUV surveys as it increases the utility of initial dives. It also delivers a comprehensive training set to learn a relationship between acoustic bathymetry and visually-derived seafloor classifications.