cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
The Abundance of Deuterium in the Warm Neutral Medium of the Lower Galactic Halo
Creators: name: Savage, Blair
name: Lehner, Nicolas
name: Fox, Andrew
name: Wakker, Bart
name: Sembach, Kenneth
Publisher: name: arXiv
Year: 2007
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: We use high resolution spectra obtained with FUSE and STIS to obtain interstellar column densities of H I, D I, O I, S II, Fe II and P II toward the QSO HE 0226-4110 ( l = 253.4 deg , b = -65.77 deg). We obtain D/H = 21(+8, -6) ppm. Correcting for a small amount of contamination from D and H in the Local Bubble, we obtain D/H = 22 (+8, -6) for the warm neutral medium of the lower Galactic halo. The medium has [O/H] = 0.12(+0.41, -0.20) and [Fe/H] = -1.01 (+0.10, -0.09). This suggests the abundances in the halo toward HE 0226-4110 are not affected by the infall of low metallicity gas and that the gas originates in the disk and is elevated into the halo by energetic processes which erode but do not totally destroy the dust grains. We compare our result to measured values of D/H in other astrophysical sites. The value we measure in the halo gas is consistent with the hypothesis that for many Galactic disk lines of sight D is incorporated into dust. The high average value of D/H = 23.1+/-2.4 ppm measured along 5 sight lines through disk gas in the Solar neighborhood is similar to D/H in the lower Galactic halo. These observations imply the abundance of deuterium in the Galaxy has only been reduced by a factor of 1.12+/-0.13 since its formation.
description: 41 pages including 7 figures. Accepted by ApJ
Stable Higher-Order Topological Dirac Semimetals with $\mathbb{Z}_2$ Monopole Charge in Alternating-twisted Multilayer Graphenes and beyond
Creators: name: Qian, Shifeng
name: Li, Yongpan
name: Liu, Cheng-Cheng
Publisher: name: arXiv
Year: 2023
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: We demonstrate that a class of stable $\mathbb{Z}_2$ monopole charge Dirac point ($\mathbb{Z}_2$DP) phases can robustly exist in real materials, which surmounts the understanding: that is, a $\mathbb{Z}_2$DP is unstable and generally considered to be only the critical point of a $\mathbb{Z}_2$ nodal line ($\mathbb{Z}_2$NL) characterized by a $\mathbb{Z}_2$ monopole charge (the second Stiefel-Whitney number $w_2$) with space-time inversion symmetry but no spin-orbital coupling. For the first time, we explicitly reveal the higher-order bulk-boundary correspondence in the stable $\mathbb{Z}_2$DP phase. We propose the alternating-twisted multilayer graphene, which can be regarded as 3D twisted bilayer graphene (TBG), as the first example to realize such stable $\mathbb{Z}_2$DP phase and show that the Dirac points in the 3D TBG are essential degenerate at high symmetric points protected by crystal symmetries and carry a nontrivial $\mathbb{Z}_2$ monopole charge ($w_2=1$), which results in higher-order hinge states along the entire Brillouin zone of the $k_z$ direction. By breaking some crystal symmetries or tailoring interlayer coupling we are able to access $\mathbb{Z}_2$NL phases or other $\mathbb{Z}_2$DP phases with hinge states of adjustable length. In addition, we present other 3D materials which host $\mathbb{Z}_2$DPs in the electronic band structures and phonon spectra. We construct a minimal eight-band tight-binding lattice model that captures these nontrivial topological characters and furthermore tabulate all possible space groups to allow the existence of the stable $\mathbb{Z}_2$DP phases, which will provide direct and strong guidance for the realization of the $\mathbb{Z}_2$ monopole semimetal phases in electronic materials, metamaterials and electrical circuits, etc.
description: PRB Letter, in press
Computing Groebner bases of ideals of few points in high dimensions
Creators: name: Just, Winfried
name: Stigler, Brandilyn
Publisher: name: arXiv
Year: 2006
Subjects: subject: Commutative Algebra (math.AC)
subject: FOS: Mathematics
subject: 13P10

description: A contemporary and exciting application of Groebner bases is their use in computational biology, particularly in the reverse engineering of gene regulatory networks from experimental data. In this setting, the data are typically limited to tens of points, while the number of genes or variables is potentially in the thousands. As such data sets vastly underdetermine the biological network, many models may fit the same data and reverse engineering programs often require the use of methods for choosing parsimonious models. Grobner bases have recently been employed as a selection tool for polynomial dynamical systems that are characterized by maps in a vector space over a finite field. While there are numerous existing algorithms to compute Groebner bases, to date none has been specifically designed to cope with large numbers of variables and few distinct data points. In this paper, we present an algorithm for computing Grobner bases of zero-dimensional ideals that is optimized for the case when the number m of points is much smaller than the number n of indeterminates. The algorithm identifies those variables that are essential, that is, in the support of the standard monomials associated to a polynomial ideal, and computes the relations in the Groebner bases in terms of these variables. When n is much larger than m, the complexity is dominated by nm^3. The algorithm has been implemented and tested in the computer algebra system Macaulay 2. We provide a comparison of its performance to the Buchberger-Moeller algorithm, as built into the system.
description: 11 pages, 4 figures. Minor clarifying revisions including typos, a reference, and title change. To appear in Communications in Computer Algebra
Complexity of near-optimal robust versions of multilevel optimization problems
Creators: name: Besançon, Mathieu
name: Anjos, Miguel F.
name: Brotcorne, Luce
Publisher: name: arXiv
Year: 2020
Subjects: subject: Optimization and Control (math.OC)
subject: Computational Complexity (cs.CC)
subject: FOS: Mathematics
subject: FOS: Computer and information sciences

description: Near-optimality robustness extends multilevel optimization with a limited deviation of a lower level from its optimal solution, anticipated by higher levels. We analyze the complexity of near-optimal robust multilevel problems, where near-optimal robustness is modelled through additional adversarial decision-makers. Near-optimal robust versions of multilevel problems are shown to remain in the same complexity class as the problem without near-optimality robustness under general conditions.
Update on the physics of light pseudoscalar mesons
Creators: name: The MILC Collaboration
name: Bernard, C.
name: DeTar, C.
name: Gottlieb, Steven
name: Heller, U. M.
name: Hetrick, J. E.
name: Levkova, L.
name: Osborn, J.
name: Renner, D.
name: Sugar, R.
name: Toussaint, D.
Publisher: name: arXiv
Year: 2006
Subjects: subject: High Energy Physics - Lattice (hep-lat)
subject: FOS: Physical sciences

description: We present an update of the MILC investigation of the properties of light pseudoscalar mesons using three flavors of improved staggered quarks. Results are presented for the $π$ and $K$ leptonic decay constants, the CKM matrix element $V_{us}$, the up, down and strange quark masses, and the coefficients of the $O(p^4)$ chiral lagrangian. We have new data for lattice spacing $a \approx 0.15$ fm with several values of the light quark mass down to one-tenth the strange quark mass, higher statistics for $a \approx 0.09$ fm with the light quark mass equal to one-tenth the strange quark mass, and initial results for our smallest lattice spacing, $a \approx 0.06$ fm with light quark mass two-fifths of the strange quark mass.
description: 7 pages, 4 figures. To be published in Proceedings of Science (Lattice 2006) 163 (2006)
A High Order Geometry Conforming Immersed Finite Element for Elliptic Interface Problems
Creators: name: Adjerid, Slimane
name: Lin, Tao
name: Meghaichi, Haroun
Publisher: name: arXiv
Year: 2023
Subjects: subject: Numerical Analysis (math.NA)
subject: FOS: Mathematics
subject: G.1.8
subject: 65N30

description: We present a high order immersed finite element (IFE) method for solving the elliptic interface problem with interface-independent meshes. The IFE functions developed here satisfy the interface conditions exactly and they have optimal approximation capabilities. The construction of this novel IFE space relies on a nonlinear transformation based on the Frenet-Serret frame of the interface to locally map it into a line segment, and this feature makes the process of constructing the IFE functions cost-effective and robust for any degree. This new class of immersed finite element functions is locally conforming with the usual weak form of the interface problem so that they can be employed in the standard interior penalty discontinuous Galerkin scheme without additional penalties on the interface. Numerical examples are provided to showcase the convergence properties of the method under $h$ and $p$ refinements.
description: V1: 29 pages. V2: 25 pages (changed font from 11pt to the default 10pt)
The two-body open charm decays of $Z^+(4430)$
Creators: name: Liu, Xiang
name: Zhang, Bo
name: Zhu, Shi-Lin
Publisher: name: arXiv
Year: 2008
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: High Energy Physics - Experiment (hep-ex)
subject: FOS: Physical sciences

description: The two-body open charm decays $Z^+(4430)\to D^{+}\bar{D}^{*0}, D^{*+}\bar{D}^{0}, D^{*+}\bar{D}^{*0}$ occur through the re-scattering mechanism and their branching ratios are strongly suppressed if $Z^+(4430)$ is a $D_1\bar D^*$ molecular state. In contrast, $Z^+(4430)$ falls apart into these modes easily with large phase space and they become the main decay modes if $Z^+(4430)$ is a tetraquark state. Experimental search of these two-body open charm modes and the hidden charm mode $χ_{cJ}ρ$ will help distinguish different theoretical schemes.
description: 6 pages, 3 figures, 1 table
The Electron Proton Helium INstrument as an Example for a Space Weather Radiation Instrument
Creators: name: Kühl, Patrick
name: Heber, Bernd
name: Gómez-Herrero, Raúl
name: Malandraki, Olga
name: Posner, Arik
name: Sierks, Holger
Publisher: name: arXiv
Year: 2020
Subjects: subject: Space Physics (physics.space-ph)
subject: FOS: Physical sciences

description: The near-Earth energetic particle environment has been monitored since the 1970's. With the increasing importance of quantifying the radiation risk for, e.g. for the human exploration of the Moon and Mars, it is essential to continue and further improve these measurements. The Electron Proton Helium INstrument (EPHIN) on-board SOHO continually provides these data sets to the solar science and space weather communities since 1995. Here, we introduce the numerous data products developed over the years and present space weather related applications. Important design features that have led to EPHINs success as well as lessons learned and possible improvements to the instrument are also discussed with respect to the next generation of particle detectors.
Η διαδικασία συν-δημιουργίας των προϊόντων και η δέσμευση των καταναλωτών σε ένα εμπορικό σήμα
Creators: name: Μουρτζίνος, Ανδρέας Θεόδωρου
Publisher: name: Aristotle University of Thessaloniki
Year: 2015
Subjects: δέσμευση
συν-δημιουργία
εμπορικό σήμα
engagement
co-creation
brand

description: Όσο περισσότερο μελετάται το σύγχρονο μοντέλο της κυριαρχίας των υπηρεσιών, έχει παρατηρηθεί ένα αυξημένο ενδιαφέρον στην έννοια της δέσμευσης και της συν-δη-μιουργίας. Η έννοια της δέσμευσης έχει ερευνηθεί σε βάθος δίχως ωστόσο να υπάρχει ομοφωνία στο θεωρητικό πλαίσιο που τη διέπει. Επιπρόσθετα, η συν-δημιουργία, ως νεοανακαλυφθείς όρος, δεν έχει ερευνηθεί αρκετά η σημασία του στο σύγχρονο επι-χειρησιακό περιβάλλον. Ως εκ τούτου, δεν έχει ερευνηθεί σε βάθος και η σχέση που εμφανίζουν οι δύο έννοιες μεταξύ τους καθώς και οι παράγοντες που καθιστούν τους καταναλωτές να δεσμευτούν και να αλληλεπιδράσουν με μία επιχείρηση. Σκοπός επο-μένως, της παρούσας έρευνας είναι η αποσαφήνιση των δύο όρων, οι σχέσεις που τις συνδέουν και οι παράγοντες που υποκινούν τους καταναλωτές να αναμιχθούν με την επιχείρηση, να δεσμευτούν, να συν-δημιουργήσουν αξία, καταλήγοντας στην προσή-λωση σε ένα εμπορικό σήμα. Παρουσιάζεται ένα θεωρητικό πλαίσιο και ένα μοντέλο που συνδέει αυτούς τους όρους ενώ ακολουθεί στατιστική ανάλυση για την ισχυροποί-ηση των αποτελέσματα αυτών. Πιο συγκεκριμένα για την υποστήριξη του θεωρητικού πλαισίου και για την εύρεση ενός μοντέλου που εσωκλείει την εν λόγω θεωρία, η έ-ρευνα, προσπαθεί να κατανοήσει τις σχέσεις των καταναλωτών με την υπηρεσία κινη-τής τηλεφωνίας που εμπιστεύονται.
description: The more we studied the contemporary model of services dominant logic (S-D Logic), has seen an increased interest in the concept of two terms, engagement and co-creation. The concept of engagement has been investigated in depth without unanimity in its theoretical framework. Additionally, the importance of co-creation, hasnotbeeninves-tigatedsufficientlyenough, as it is a newly confirmed term, inmodernenterpriseenvi-ronment. Therefore, the relationship that bounds together the two concepts as well as the factors that motivate consumers to engage and interact with a brand, has not been investigated thoroughly. Consequently the purpose of this research is toclarifythecon-ceptualframeworksofthe two terms, the relations connecting them and the factors that drive consumers to involve, engage and co-create value, resulting in brand loyalty. In order to achieve this, a theoretical framework and a model are being presented for the causal relationships between those terms followed by statistical analysis strengthening those results. Particularly, to support the theoretical framework for establishing a model that encloses the proposed theory, the research, attempts to understand the interactions between consumers and mobile service providers.
Principal subspaces of higher-level standard sl(3)^-modules
Creators: name: Calinescu, Corina
Publisher: name: arXiv
Year: 2006
Subjects: subject: Quantum Algebra (math.QA)
subject: Representation Theory (math.RT)
subject: FOS: Mathematics
subject: 17B69, 17B65

description: We use the theory of vertex operator algebras and intertwining operators to obtain systems of q-difference equations satisfied by the graded dimensions of the principal subspaces of certain level k standard modules for \hat{\goth{sl}(3)}. As a consequence we establish new formulas for the graded dimensions of the principal subspaces corresponding to the highest-weights iΛ_1+(k-i)Λ_2, where 1 \leq i \leq k and Λ_1 and Λ_2 are fundamental weights of \hat{\goth{sl}(3)}.
description: 25 pages; v2: minor revisions
Το Ισλάμ στους Βυζαντινούς συγγραφείς του 7ου & 8ου αιώνα
Creators: name: Τσούμας, Ευάγγελος Ανδρέα
Publisher: name: Aristotle University of Thessaloniki
Year: 2015
Subjects: Ισλάμ
Βυζαντινοί συγγραφείς
Άραβες
Islam
Byzantine writers
Arabs

description: Σκοπός της παρούσας εργασίας υπήρξε αρχικά, η παρουσίαση της ιστορικής πορείας των μουσουλμάνων Αράβων τον 7ο αιώνα και η κατάδειξη της αλληλεπίδρασης των σχέσεων που προκλήθηκε μεταξύ των Αράβων και των χριστιανών έως τον 8ο αιώνα. Εντούτοις, η παρουσίαση των επιμέρους θέσεων πολλών Βυζαντινών συγγραφέων του 7ου και 8ου αιώνα, οι οποίοι ασχολήθηκαν διεξοδικά με το Ισλάμ, αποτέλεσε τον κεντρικό και κύριο τομέα της εργασίας μας. Η λεπτομερής και πολλές φορές ειδική αναφορά σε συγκεκριμένα έργα τους, αποτυπώνει και την σημαντικότητα των παραπάνω κειμένων. Τέλος, προσπαθήσαμε να καταδείξουμε τις κεντρικές θέσεις τους για το Ισλάμ, ώστε να καταστεί δυνατή η κατανόηση, τόσο της βυζαντινής σκέψης για τη νέα αυτή θρησκεία, όσο και οι επιμέρους πτυχές της ισλαμικής διδασκαλίας, κυρίως από θρησκειολογική σκοπιά. Οι Βυζαντινοί συγγραφείς, που ασχολήθηκαν με το Ισλάμ κατά τον 7ο και 8ο αιώνα, μας έδωσαν πολύτιμα στοιχεία για την παραπάνω εμφανισθείσα θρησκεία στα ανατολικά της Βυζαντινής Αυτοκρατορίας και τα συγγράμματά τους αποτέλεσαν ιδιαίτερα κείμενα μελέτης από πολλούς μεταγενέστερους ερευνητές και επιστήμονες. Οι ίδιοι διαδραμάτισαν σπουδαίο ρόλο στην ανάπτυξη της κατανόησης της διαφορετικότητας του Ισλάμ.
description: The aim of the present work was first, the presentation of the historical emergence of Muslim Arabs in the 7th century and demonstration of the interaction of relations caused among Arabs and Christians until the 8th century. However, the presentation of individual positions in several Byzantine writers of the 7th and 8th century, who comprehensively have dealt with Islam, constituted the central and main sector of our work. The detailed and sometimes specific reference to particular works, reflects the importance of the above texts. Finally, we tried to demonstrate the central positions on Islam, to enable the understanding of both the Byzantine thinking about this new religion, and the various aspects of Islamic teaching, mainly from religious viewpoint. The Byzantine writers who have dealt with Islam in the 7th and 8th century, gave us valuable information on the above religion in the east of the Byzantine Empire and their writings were particularly study texts by many subsequent researchers and scientists. They played an important role in developing understanding of the diversity of Islam.
Estimating harvesting productivity and cost on second-growth coastal sites in British Columbia
Creators: name: Jukes, W. D.
Publisher: name: University of British Columbia
Year: 2009

description: In 1991 the Forest Engineering Research Institute of Canada and the Faculty of Forestry at the University of British Columbia initiated a four year cooperative project for the Canadian Forest Service to estimate harvesting system productivity and costs for clearcutting second-growth coastal sites of British Columbia. The overall objectives were to develop productivity and cost prediction models for common harvesting systems operating in second-growth stands and to design a framework for a model to select the best harvesting system for a given area based on costs. Two harvesting operations in coastal second-growth forests on Vancouver Island were monitored. This included mechanical and manual felling, and primary timber extraction with combinations of modified hydraulic log loaders (excavator-forwarders) and long-boom loaders (super-snorkels). Studies measured machine productivities and identified factors that influenced machine performance. Model framework design incorporated production functions derived from time studies, optimal placement of roads and landings, and machine and operating costing methods.
title: Business Crime: The Perception and Experience of Victimization and Corresponding Use of Crime Prevention Measures
Creators: name: Casten, John A.
Publisher: name: Old Dominion University
publisherIdentifier: https://ror.org/04zjtrb98
publisherIdentifierScheme: ROR
Year: 2004

description: This study uses the concepts of routine activities theory and social disorganization theory to examine some of the factors that influence a business owner's use of crime prevention measures. I predicted that neighborhood conditions as well as personal experience with crime would influence a business owner's decision to use crime prevention measures. In addition, I controlled for sex, race, age, education level, and police presence.

The results of the study were fairly consistent with the hypothesis except for two of the variables. In this particular study, age was not a significant factor in predicting the use of crime prevention measures, which is contrary to most literature. Also surprising was that the perception of positive neighborhood characteristics was much more significant than the perception of negative neighborhood characteristics.
FACTORS DETERMINING INTERNATIONAL TOURIST FLOW TO TOURISM DESTINATIONS: A SYSTEMATIC REVIEW
Creators: name: Tsegaye, Wondimu Abera
name: Yohannes Mulugeta, Assefa
Publisher: name: Klover
Year: 2024
Subjects: Travel and tourism, Economic impact, International tourist arrivals, Sustainability, Globalization.

description: The travel and tourism industry stands as a vital pillar of the global economy, serving as a significant source of revenue, employment, and investment for numerous countries. With its widespread impact on consumption, infrastructure development, and gross domestic product, the industry plays a pivotal role in fostering economic growth and development. This paper examines the multifaceted contributions of travel and tourism to national economies, drawing upon empirical evidence and scholarly research.

International tourism, in particular, serves as a key driver of economic prosperity, generating foreign exchange earnings and stimulating employment opportunities. The steady increase in tourist arrivals, propelled by globalization and market liberalization trends, underscores the industry's resilience and significance in the global marketplace. Following the historic milestone of one billion international travelers in 2012, tourism has continued to experience robust growth, with average annual growth rates surpassing 4.88% in recent years.

In 2018, international tourist arrivals surpassed 1.4 billion, marking a 5% increase from the previous year, and this growth trajectory is expected to persist in 2019 with a projected growth rate of 4-5%. Such trends highlight the continued expansion of the tourism industry and its enduring appeal to travelers worldwide. Both public and private sectors have made substantial investments in tourism infrastructure and services to capitalize on this growth potential.

However, alongside its economic benefits, tourism also presents challenges related to sustainability, cultural preservation, and environmental conservation. As tourist flows continue to increase, destinations must prioritize responsible tourism practices to mitigate negative impacts on local communities and ecosystems.

This paper underscores the importance of balanced tourism development strategies that prioritize economic growth while safeguarding cultural and natural heritage. By fostering collaboration between stakeholders and adopting sustainable tourism practices, countries can harness the full potential of the travel and tourism industry for inclusive and sustainable development.
Η προοπτική ένταξης των Δυτικών Βαλκανίων στην Ευρωπαϊκή Ένωση υπό το πρίσμα της οικονομικής κρίσης
Creators: name: Αποστολίδου, Σοφία Αντωνίου
Publisher: name: Aristotle University of Thessaloniki
Year: 2015
Subjects: Δυτικά Βαλκάνια
Ευρωπαϊκή Ένωση
Οικονομική κρίση
Western Balkans
European Union
Economic crisis

description: Η παρούσα μεταπτυχιακή εργασία διερευνά την προοπτική ένταξης των χωρών των Δυτικών Βαλκανίων στην Ευρωπαϊκή Ένωση, υπό το πρίσμα της οικονομικής κρίσης. Aρχικά περιγράψαμε συνοπτικά τις σχέσεις των χωρών των Δυτικών Βαλκανίων με την Ευρωπαϊκή Ένωση, από τη διάλυση της πρώην Σοσιαλιστικής Ομοσπονδιακής Δημοκρατίας της Γιουγκοσλαβίας μέχρι την εμφάνιση της οικονομικής κρίσης. Στη συνέχεια εξετάσαμε τη σχέση μεταξύ οικονομικής κρίσης και ευρωπαϊκής προοπτικής των χωρών των Δυτικών Βαλκανίων. Ακόμη, εστιάσαμε σε ζητήματα όπως ο εθνικισμός και η διαφθορά, τα οποία αποτελούν «αγκάθια» στην πορεία ένταξης των χωρών των Δυτικών Βαλκανίων στην Ευρωπαϊκή Ένωση. Αποδείξαμε ότι η οικονομική κρίση επηρέασε σημαντικά την ευρωπαϊκή προοπτική των χωρών των Δυτικών Βαλκανίων, εφόσον πάγωσε την πολιτική διεύρυνσης της Ευρωπαϊκής Ένωσης και αποδυνάμωσε την ικανότητα των χωρών να ολοκληρώσουν τις απαιτούμενες μεταρρυθμίσεις και να εκπληρώσουν τα κριτήρια για την προσχώρησή τους στην Ευρωπαϊκή Ένωση
description: Τhis thesis deals with the accession perspective of the Western Balkans to the European Union, in light of the current economic crisis. First, we briefly described the European Union relations with the Western Balkan countries, from the dismantling of the former Socialist Federal Republic of Yugoslavia to the 2008 economic crisis. Second, we examined the relationship between recession and accession possibilities for the Western Balkans. Third, we focused on issues such as nationalism and corruption, which are the main obstacles in allowing Western Balkan countries to join the European Union. Finally, we demonstrated that economic crisis affected significantly the European perspective of the Western Balkans, since it suspended the enlargement policy of the European Union, thus impeding Western Balkan countries’ capability to complete all necessary reforms in order to fulfill the criteria for accession into the European Union.
Electronic, magnetic and optical properties of penta-BN$_2$ nanoribbons: a first principles study
Creators: name: Dantas, M. A. L.
name: Frazão, N. F.
name: Azevedo, David L.
name: Lima, Jonas R. F.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: The search for new materials is a very intense task in many technological areas. In 2015, a new variant of graphene was proposed, the pentagraphene, which was followed by the propose of a pentagonal boron nitride structure called penta-BN$_2$. Based on these structures, we investigated the electronic, magnetic, and optical properties of penta-BN$_2$ nanoribbons (p-BNNRs) considering four different kinds of edges, carefully closing the valence shells with H atoms to prevent dangling bonds. To achieve this goal, we used first-principles calculations in a density functional theory framework. Our findings showed that the p-BNNRs have a rich magneto-electronic behavior, varying from semiconductor to half-metal. We obtained that they are ferrimagnetic, having an intrinsic magnetism, which allow potential applications in spintronic or spinwaves. From an optical absorption point of view, they mainly absorb at ultraviolet region of the spectrum, especially at UV-B region, which could indicate a potential application as a UV filter.
General adaptive rational interpolation with maximum order close to discontinuities
Creators: name: Arandiga, Francesc
name: Yanez, Dionisio F.
Publisher: name: arXiv
Year: 2020
Subjects: subject: Numerical Analysis (math.NA)
subject: FOS: Mathematics

description: Adaptive rational interpolation has been designed in the context of image processing as a new nonlinear technique that avoids the Gibbs phenomenon when we approximate a discontinuous function. In this work, we present a generalization to the method giving explicit expressions for all the weights for any order of the algorithm. It has a similar behavior to weighted essentially non oscillatory (WENO) technique, however because of the design of the weights in this case is more simple, we propose a new way to construct them obtaining the maximum order near the discontinuities. Some experiments are performed to demonstrate our results and to compare them with standard methods.
Magnetic Susceptibility of the Kagome Antiferromagnet ZnCu3(OH)6Cl2
Creators: name: Rigol, Marcos
name: Singh, Rajiv R. P.
Publisher: name: arXiv
Year: 2007
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: Statistical Mechanics (cond-mat.stat-mech)
subject: FOS: Physical sciences

description: We analyze the experimental data for the magnetic susceptibility of the material ZnCu3(OH)6Cl2 in terms of the Kagome Lattice Heisenberg model (KLHM), discussing possible role of impurity spins, dilution, exchange anisotropy, and both out-of-plane and in-plane Dzyaloshinsky-Moriya (DM) anisotropies, with explicit theoretical calculations using the Numerical Linked Cluster (NLC) method and exact diagonalization (ED). The high-temperature experimental data are well described by the pure Heisenberg model with J=170 K. We show that the sudden upturn in the susceptibility around T=75 K is due to DM interactions. We also observe that at intermediate temperatures, below T=J, our calculated susceptibility for KLHM fits well with a power law T^{-0.25}.
description: 4 pages, 5 figures, published version
Στατιστική ανάλυση και μοντελοποίηση της αγωνιστικής επίδοσης ιστιοπλοϊκών σκαφών
Creators: name: Τσαουσίδου, Μαρία Δημητρίου
Publisher: name: Aristotle University of Thessaloniki
Year: 2015
Subjects: στατιστική ανάλυση
μοντελοποίηση
ιστιοπλοΐα
statistical analysis
modeling
sailing

description: Η παρούσα διπλωματική αποτελεί μια πρωτότυπη προσπάθεια μοντελοποίησης του αγωνίσματος της ιστιοπλοΐας, βελτίωσης της απόδοσης ενός ιστιοπλοϊκού σκάφους μέσα από τη στατιστική ανάλυση της επίδοσής του και σύγκρισης των δεδομένων πολλών ίδιων σκαφών κατά τη διάρκεια των ιστιοδρομιών ενός αγώνα. Μετά την επεξήγηση του τρόπου διεξαγωγής των αγώνων ιστιοπλοΐας και του τρόπου μελέτης των λεγόμενων πολικών διαγραμμάτων, γίνεται εφαρμογή και ανάλυση της απόδοσης του σκάφους “Alegre3” κατά τη διάρκεια του αγώνα Palma Vela για το 2014. Ακολουθούν η στατιστική ανάλυση των δεδομένων των 7 σκαφών που συμμετέχουν στον αγώνα Volvo Ocean Race 2014-15 και τα συμπεράσματα των εφαρμογών.
description: This master thesis is a major effort of modeling the sport of sailing and of improving the performance of a sailing boat by using the statistical analysis of its performance during a race. After explaining the pattern of sailing races and the use of polar graphs, the performance of “Alegre3” boat during the Palma Vela championship in 2014 is being analysed by applying multiple and linear regressions to the variables that describe the boat. After that, we analyse the performance of the seven boats that participated in the first leg of 2014-15 Volvo Ocean Race and mention the results of these applications.
Ελληνικοί παραδοσιακοί χοροί: Σύγχρονες επιτελέσεις και χορευτικές δράσεις
Creators: name: Φωτιάδου, Μαριάννα Θεόδωρου
Publisher: name: Aristotle University of Thessaloniki
Year: 2015
Subjects: Ελληνικοί παραδοσιακοί χοροί
Επιτέλεση παραδοσιακών χορών
Ελληνική παράδοση
Greek traditional dances
Performance of traditional dances
Greek tradition
3. Παράδοση
ΛΕΞΕΙΣ ή ΦΡΑΣΕΙΣ ΚΛΕΙΔΙΑ (ΑΓΓΛΙΚΑ)
1. Greek traditional dances
2. Performance
3. Tradition

description: Το θέμα της παρούσας εργασίας είναι οι σύγχρονες επιτελέσεις των ελληνικών παραδοσιακών χορών, από χορευτικές ομάδες πολιτιστικών συλλόγων που λειτουργούν στις πόλεις. Το θέμα αυτό προσεγγίζεται μέσα από το εθνογραφικό παράδειγμα της Παρέας, ενός συλλόγου που εδρεύει στην πόλη της Θεσσαλονίκης. Οι χορευτικές επιτελέσεις εξετάζονται υπό το πρίσμα των χορευτικών δράσεων των παραπάνω συλλόγων, στο πλαίσιο δύο χορευτικών περιστάσεων, της πρόβας και της παράστασης. Συγκεκριμένα, μελετώνται οι τρόποι με τους οποίους οι ελληνικοί παραδοσιακοί χοροί υποστασιοποιούνται σε διδακτικό και παραστασιακό αντικείμενο και λειτουργούν, τελικά, ως συνεκδοχή της παράδοσης. Έτσι, σε αυτή την εργασία η παράδοση δεν αντιμετωπίζεται ως ένας στατικός ή ιδεολογικός όρος. Αντίθετα, προτείνεται η θεώρηση της παράδοσης ως πραγματικότητα, δηλαδή ως μέρος της καθημερινότητας αλλά και ως πλαίσιο για την επαναδιαπραγμάτευση ζητημάτων, που αφορούν τα όρια της παράδοσης και τα ζητήματα της αυθεντικότητας.
description: The subject of this thesis is the contemporary performances of greek traditional dances by dance troupes of cultural associations operating in greek cities. This issue is approached through the ethnographic example of the Parea, a cultural association which is located in the city of Thessaloniki. The dance performances are examined through the aspect of these dance troupes’ actions, in the context of two dance occasions, the rehearsal and the dance performance. In particular, the research is focused on the ways through which the greek traditional dances are substantiated into a teaching and performing object and, finally, they function as a connotation of tradition. Thus, in this thesis tradition is not considered to be a static and ideological term. On the contrary, it is suggested to approach tradition as reality, namely as a part of everyday life as well as a context to renegotiate issues which are related to the boundaries of tradition and the matters of authenticity.
Multiple subglacial water bodies below the south pole of Mars unveiled by new MARSIS data
Creators: name: Lauro, Sebastian Emanuel
name: Pettinelli, Elena
name: Caprarelli, Graziella
name: Guallini, Luca
name: Rossi, Angelo Pio
name: Mattei, Elisabetta
name: Cosciotti, Barbara
name: Cicchetti, Andrea
name: Soldovieri, Francesco
name: Cartacci, Marco
name: Di Paolo, Federico
name: Noschese, Raffaella
name: Orosei, Roberto
Publisher: name: arXiv
Year: 2020
Subjects: subject: Earth and Planetary Astrophysics (astro-ph.EP)
subject: Geophysics (physics.geo-ph)
subject: FOS: Physical sciences

description: The detection of liquid water by the Mars Advanced Radar for Subsurface and Ionosphere Sounding (MARSIS) at the base of the south polar layered deposits in Ultimi Scopuli has reinvigorated the debate about the origin and stability of liquid water under present-day Martian conditions. To establish the extent of subglacial water in this region, we acquired new data, achieving extended radar coverage over the study area. Here, we present and discuss the results obtained by a new method of analysis of the complete MARSIS dataset, based on signal processing procedures usually applied to terrestrial polar ice sheets. Our results strengthen the claim of the detection of a liquid water body at Ultimi Scopuli and indicate the presence of other wet areas nearby. We suggest that the waters are hypersaline perchlorate brines, known to form at Martian polar regions and thought to survive for an extended period of time on a geological scale at below-eutectic temperatures.
Broadband operation of active terahertz quarter-wave plate achieved with vanadium-dioxide-based metasurface switchable by current injection
Creators: name: Nakanishi, Toshihiro
name: Nakata, Yosuke
name: Urade, Yoshiro
name: Okimura, Kunio
Publisher: name: arXiv
Year: 2020
Subjects: subject: Optics (physics.optics)
subject: Applied Physics (physics.app-ph)
subject: FOS: Physical sciences

description: We demonstrate the broadband operation of a switchable terahertz quarter-wave plate achieved with an active metasurface employing vanadium dioxide. For this purpose, we utilize anisotropically deformed checkerboard structures, which present broadband characteristics compatible with deep modulation. Moreover, the metasurface is integrated with a current injection circuit to achieve state switching; this injection circuit can also be employed to monitor the electric state of vanadium dioxide. We estimate the Stokes parameters derived from the experimental transmission spectra of the fabricated metasurface and confirm the helicity switching of circularly polarized waves near a designed frequency of 0.66THz. The relative bandwidth is evaluated as 0.52, which is 4.2 times broader than that in a previous study.
description: 7 pages, 6 figures
The Late-T Dwarf Companion to the Exoplanet Host Star HD 3651: A New Benchmark for Gravity and Metallicity Effects in Ultracool Spectra
Creators: name: Liu, Michael C.
name: Leggett, S. K.
name: Chiu, Kuenley
Publisher: name: arXiv
Year: 2007
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: (Abridged) We present near-IR photometry and spectroscopy of HD 3651B, the low-luminosity, wide-separation (480 AU) companion to the K0V exoplanet host star HD 3651A. We find a spectral type of T7.5+/-0.5, a temperature of 780-840 K, and a mass of 40-72 Mjup; its bolometric luminosity and effective temperature are among the lowest measured for any brown dwarf. We estimate an age of 3-12 Gyr for the primary star HD 3651A and find that it is ~3x older than the K4V star Gl 570A (1-5 Gyr), the host star of the T7.5 dwarf Gl 570D. HD 3651B belongs to the rare class of substellar objects that are companions to main-sequence stars and thus provides a new benchmark for studying very low-temperature objects. Given their similar temperatures (within ~30 K) and metallicities (within ~0.1 dex) but different ages, a comparison of HD 3651B and GL 570D allows us to examine gravity-sensitive diagnostics in ultracool spectra. We find that the expected signature of HD 3651B's higher surface gravity due to its older age, namely a suppressed K-band flux relative to GL 570D, is not seen. Instead, the K-band flux of HD 3651B is enhanced compared to GL 570D, indicative of a younger age. Thus, the relative ages derived from interpretation of T dwarf spectra and from stellar activity indicators appear to be in discord. One likely explanation is that the K-band fluxes are also very sensitive to metallicity differences. Metallicity variations may be as important as surface gravity variations in causing spectral differences among field late-T dwarfs.
description: ApJ, in press, 26 pages
How Does a Student-Centered Course on Communication and Professional Skills Impact Students in the Long Run?
Creators: name: Motschnig, Renate
name: Silber, Michael
name: Švábenský, Valdemar
Publisher: name: arXiv
Year: 2021
Subjects: subject: Computers and Society (cs.CY)
subject: FOS: Computer and information sciences

description: This Full Paper in the Research-To-Practice Category presents a long-term study about the effects of a student-centered course on communication and professional skills on students' thoughts, attitudes, and behavior. The course is offered at a European university as part of a computer science master's program. This paper shares the design and challenges of a longitudinal study that reaches ten years behind and employs a mixed-methods approach. Besides presenting and interpreting the findings, we shed light on which features tend to stay on students' minds and impact their way of being and acting in society. Moreover, we suggest implications for the design and practice in comparable courses to maximize constructive, sustainable effects, such as improved active listening, presentation skills, and openness to other perspectives. These are essential (not only) for computer science professionals. Our findings suggest that the course provided significant learning for the vast majority of respondents, including aspects such as presenting while keeping the other side in mind, managing one's stress, and becoming less shy to speak up. All in all, we aim to contribute an evidence-based source of motivation for instructors in technically focused curricula who hold a student-centered stance.
description: IEEE FIE 2020 conference, 9 pages, 1 figure, 2 tables
Response of the warm absorber cloud to a variable nuclear flux in active galactic nuclei
Creators: name: Chevallier, L.
name: Czerny, B.
name: Rozanska, A.
name: Goncalves, A. C.
Publisher: name: arXiv
Year: 2007
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: Recent modeling of the warm absorber in active galactic nuclei has proved the usefulness of constant total (gas plus radiation) pressure models, which are highly stratified in temperature and density. We explore the consistency of those models when the typical variation of the flux from the central source is taken into account. We perform a variability study of the warm absorber response, based on timescales and our photoionization code TITAN. We show that the ionization and recombination timescales are much shorter than the dynamical timescale. Clouds very close to the central black hole will maintain their equilibrium since the characteristic variability timescales of the nuclear source are longer than cloud timescales. For more distant clouds, the density structure has no time to vary, in response to the variations of the temperature or ionization structure, and such clouds will show the departure from the constant pressure equilibrium. We explore the impact of this departure on the observed properties of the transmitted spectrum and soft X-ray variability: (i) non uniform velocities, of the order of sound speed, appear due to pressure gradients, up to typical values of 100 km/s. These velocities lead to the broadening of lines. This broadening is usually observed and very difficult to explain otherwise. (ii) Energy-dependent fractional variability amplitude in soft X-ray range has a broader hump around ~ 1-2 keV, and (iv) the plot of the equivalent hydrogen column density vs. ionization parameter is steeper than for equilibrium clouds. The results have the character of a preliminary study and should be supplemented in the future with full time-dependent radiation transfer and dynamical computations.
description: 9 pages, 7 figures, accepted for publication by Astronomy & Astrophysics
The Tsai-Wu strength theory for Douglas-fir laminated veneer
Creators: name: Clouston, Peggi
Publisher: name: University of British Columbia
Year: 2009

description: This study investigates the determincrtion and use of a multi-axial failure criterion for Douglas-fir lcrrninated veneer. Unlike previous studies on failure theories, this study treats strength parameters as random variables as opposed to detenninistic variables. Also, size effect has been incorporated in the failure theory implementation. A comparison has been made between four established orthotopic failure theories based on off-axis tensile test data to determine the most appropriate theory of the four considered; Tscd-Hill, Norris, Tscri-Wu and Tan-Cheng theories. The Tsai-Wu tensor polynomial theory has been shown to best predict the mean values of the off-axis data considering both practicality and accuracy of the strength criteria. A non-linear mirurnization technique has been developed considering the strength parameters of the Tscri-Wu criterion to be random variables to approximate the mean and standard deviation of the interaction parameter, F12. The same statistical approach has been used to approximate a size effect adjustment factor to account for the difference in stressed volumes between the shear block specimens and the off-axis specimens. A sensitivity analysis has been conducted on the interaction parameter, F12. This study indicates that the data from the 15 degree off-axis tensile tests is more reliable than that of the other angles tested, 30, 45 and 60 degrees, in establishing the most accurate value for F12. Also, the first and second quadrants of the stress space are found to be the least sensitive to variations in F12. That is, small inaccuracies in the data obtained from tests producing these stress combinations could lead to significant errors in the effectiveness of the Tscd-Wu criterion in the third and fourth quadrants. The Tsai-Wu failure criterion has been coupled with finite element analyses in a simulation procedure to estimate the cumulative probability distribution for failure load of 30 and 45 degree off-axis 3 point bending specimens. A load configuration effect has been included in the prediction model to account for the brittle strengths, tension parallel and perpendicular to grain and shear having been developed in a uniform stress configuration. Two approaches, using Weibull weakest link theory, have been investigated to incorporate the load configuration effect. Both models provide reasonable accuracy in predicting the off-axis failure load when compared to experimental results. An alternative, less versatile approach to predicting failure load for the off-axis bending application has also been studied. This approach entails using the Tsai-Wu failure criterion to first predict off-axis tensile strengths and then, using Weibull formulation, adjusting these tensile strengths to predict off-axis bending strengths. This prediction model is also corroborated by the experimental results.
Band structure and topological phases of Pb$_{1-x-y}$Sn$_x$Mn$_y$Te by ab initio calculations
Creators: name: Łusakowski, A.
name: Bogusławski, P.
name: Story, T.
Publisher: name: arXiv
Year: 2020
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: The change in the composition of Pb$_{1-x}$Sn$_x$Te IV-VI semiconductor or in its lattice parameter can drive a transition from the topologically trivial to the topological crystalline insulator (TCI), crossing a region where the alloy is in the Weyl semimetal phase. Incorporation of the magnetic Mn ions induces strong perturbations of the electronic structure, which act on both orbital and spin variables. Our first principles calculations show that the presence of Mn shifts the TCI and the Weyl region towards higher Sn contents in Pb$_{1-x}$Sn$_x$Te. When the Mn spin polarization is finite, the spin perturbation, like the orbital part, induces changes in band energies comparable to the band gap, which widens the Weyl area. The effect opens a possibility of driving transitions between various topological phases of the system by magnetic field or by the spontaneous Mn magnetization. We also propose a new method to calculate topological indices for systems with a finite spin polarization defined based on the concept of the Chern number. These valid topological characteristics enable an identification of the three distinct topological phases of the Pb$_{1-x-y}$Sn$_x$Mn$_y$Te alloy.
description: 11 pages, 8 figures
Information criteria for astrophysical model selection
Creators: name: Liddle, Andrew R
Publisher: name: arXiv
Year: 2007
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: Model selection is the problem of distinguishing competing models, perhaps featuring different numbers of parameters. The statistics literature contains two distinct sets of tools, those based on information theory such as the Akaike Information Criterion (AIC), and those on Bayesian inference such as the Bayesian evidence and Bayesian Information Criterion (BIC). The Deviance Information Criterion combines ideas from both heritages; it is readily computed from Monte Carlo posterior samples and, unlike the AIC and BIC, allows for parameter degeneracy. I describe the properties of the information criteria, and as an example compute them from WMAP3 data for several cosmological models. I find that at present the information theory and Bayesian approaches give significantly different conclusions from that data.
description: 5 pages, no figures. Update to match version accepted by MNRAS Letters. Extra references, minor changes to discussion, no change to conclusions