cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Video-Quiz im schulischen Chinesischunterricht
Creators: name: Baran, Grzegorz
Publisher: name: CHUN – Chinesischunterricht
Year: 2024

description: Das Ziel dieses Beitrags ist die Vorstellung einer Reihe von Video-Quiz, die ich für den Chinesischunterricht entwickelt habe, sowie die Diskussion ihrer Wirksamkeit. Basierend auf dem Forschungsstand kann davon ausgegangen werden, dass Video-Quiz ein wirksames Instrument sind, solange sie zum Üben oder Wiederholen verwendet werden, und dass ihre Wirksamkeit durch kooperative Sozialformen und die Förderung der Hörstrategien gesteigert werden kann. Deutsche SchülerInnen (N = 65) finden die Video-Quiz enjoyable (0,7 auf der Skala von -2 bis +2) und praktisch alle (97%) möchten sie machen, jedoch lieber im Unterricht (49%) als zu Hause (18%). Das enjoyment der Video-Quiz korreliert positiv mit dem Alter und dem Sprachniveau, daher sollen die SchülerInnen in weniger fortgeschrittenen Gruppen vor einem Video-Quiz vorentlastet werden. Insgesamt begrüßen die SchülerInnen die Video-Quiz, weil sie mehr Abwechslung in den Unterricht bringen.
description: CHUN – Chinesischunterricht, Bd. 36 (2021): CHUN - Chinesischunterricht
Congruence Subgroups and Orthogonal Groups
Creators: name: Hauffe-Waschbüsch, Adrian
name: Krieg, Aloys
Publisher: name: arXiv
Year: 2020
Subjects: subject: Number Theory (math.NT)
subject: FOS: Mathematics
subject: 11F46, 11F55

description: We derive explicit isomorphisms between certain congruence subgroups of the Siegel modular group, the Hermitian modular group over an arbitrary imaginary-quadratic number field and the modular group over the Hurwitz quaternions of degree 2 and the discriminant kernels of special orthogonal groups SO 0 (2, n), n = 3, 4, 6. The proof is based on an application of linear algebra adapted to the number theoretical needs.
Integrated optical components on atom chips
Creators: name: Eriksson, S.
name: Trupke, M.
name: Powell, H. F.
name: Sahagun, D.
name: Sinclair, C. D. J.
name: Curtis, E. A.
name: Sauer, B. E.
name: Hinds, E. A.
name: Moktadir, Z.
name: Gollasch, C. O.
name: Kraft, M.
Publisher: name: arXiv
Year: 2005
Subjects: subject: Atomic Physics (physics.atom-ph)
subject: FOS: Physical sciences

description: We report on the integration of small-scale optical components into silicon wafers for use in atom chips. We present an on-chip fibre-optic atom detection scheme that can probe clouds with small atom numbers. The fibres can also be used to generate microscopic dipole traps. We describe our most recent results with optical microcavities and show that single-atom detection can be realised on an atom chip. The key components have been fabricated by etching directly into the atom chip silicon substrate.
description: 5 pages, 4 figures
Observation of radiation torque shot noise on an optically levitated nanodumbbell
Creators: name: van der Laan, Fons
name: Reimann, René
name: Tebbenjohanns, Felix
name: Vijayan, Jayadev
name: Novotny, Lukas
name: Frimmer, Martin
Publisher: name: arXiv
Year: 2020
Subjects: subject: Optics (physics.optics)
subject: FOS: Physical sciences

description: According to quantum theory, measurement and backaction are inextricably linked. In optical position measurements, this backaction is known as radiation pressure shot noise. In analogy, a measurement of the orientation of a mechanical rotor must disturb its angular momentum by radiation torque shot noise. In this work, we observe the shot-noise torque fluctuations arising in a measurement of the angular orientation of an optically levitated nanodumbbell. We feedback cool the dumbbell's rotational motion and investigate its reheating behavior when released from feedback. In high vacuum, the heating rate due to radiation torque shot noise dominates over the thermal and technical heating rates in the system.
description: Removed typo in author list
Interaktion zwischen dem Progressiv und den Modalverben im Deutschen und im modernen Chinesisch
Creators: name: ZENG, Zhen
Publisher: name: CHUN – Chinesischunterricht
Year: 2024

description: Dieser Beitrag beschäftigt sich mit einer sprachvergleichenden Untersuchung zum Verhältnis zwischen der Aspektkategorie Progressiv und der Semantik der Modalverben im Deutschen und im modernen Chinesisch. Als Ausgangspunkt werden das Tempus und der Aspekt anhand des Ansatzes von Klein (1994) beschrieben. Das Tempus- und Aspektsystem und der Progressiv in beiden Sprachen werden untersucht und einander gegenübergestellt. Die Lesarten der Modalverben in beiden Sprachen werden in Kombination mit dem Progressiv diskutiert. Die Ergebnisse sollen dazu beitragen, die Interaktion zwischen dem Aspekt und der Modalität in beiden Sprachen zu erläutern.
description: CHUN – Chinesischunterricht, Bd. 36 (2021): CHUN - Chinesischunterricht
Transformed Dissipation in Superconducting Quantum Circuits
Creators: name: Neeley, Matthew
name: Ansmann, M.
name: Bialczak, Radoslaw C.
name: Hofheinz, M.
name: Katz, N.
name: Lucero, Erik
name: O'Connell, A.
name: Wang, H.
name: Cleland, A. N.
name: Martinis, John M.
Publisher: name: arXiv
Year: 2008
Subjects: subject: Superconductivity (cond-mat.supr-con)
subject: FOS: Physical sciences

description: Superconducting quantum circuits must be designed carefully to avoid dissipation from coupling to external control circuitry. Here we introduce the concept of current transformation to quantify coupling to the environment. We test this theory with an experimentally-determined impedance transformation of $\sim 10^5$ and find quantitative agreement better than a factor of 2 between this transformation and the reduced lifetime of a phase qubit coupled to a tunable transformer. Higher-order corrections from quantum fluctuations are also calculated with this theory, but found not to limit the qubit lifetime. We also illustrate how this simple connection between current and impedance transformation can be used to rule out dissipation sources in experimental qubit systems.
description: 4 pages, 4 figures
Qubit measurement using a quantum point contact with a quantum Langevin equation approach
Creators: name: Dong, Bing
name: Horing, Norman J. M.
name: Lei, X. L.
Publisher: name: arXiv
Year: 2005
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: We employ a quantum Langevin equation approach to establish non-Markovian dynamical equations, on a fully microscopic basis, to investigate the measurement of the state of a coupled quantum dot qubit by a nearby quantum point contact. The ensuing Bloch equations allow us to examine qubit relaxation and decoherence induced by measurement, and also the noise spectrum of meter output current with the help of a quantum regression theorem, at arbitrary bias-voltage and temperature. Our analyses provide a clear resolution of a recent debate concerning the occurrence of a quantum oscillation peak in the noise spectrum.
description: 5 pages, 3 figures, submitted, published version in Phys. Rev. B
Relativistic Continuum Hartree Bogoliubov Theory for Ground State Properties of Exotic Nuclei
Creators: name: Meng, J.
name: Toki, H.
name: Zhou, S. G.
name: Zhang, S. Q.
name: Long, W. H.
name: Geng, L. S.
Publisher: name: arXiv
Year: 2005
Subjects: subject: Nuclear Theory (nucl-th)
subject: FOS: Physical sciences

description: The Relativistic Continuum Hartree-Bogoliubov (RCHB) theory, which properly takes into account the pairing correlation and the coupling to (discretized) continuum via Bogoliubov transformation in a microscopic and self-consistent way, has been reviewed together with its new interpretation of the halo phenomena observed in light nuclei as the scattering of particle pairs into the continuum, the prediction of the exotic phenomena -- giant halos in nuclei near neutron drip line, the reproduction of interaction cross sections and charge-changing cross sections in light exotic nuclei in combination with the Glauber theory, better restoration of pseudospin symmetry in exotic nuclei, predictions of exotic phenomena in hyper nuclei, and new magic numbers in superheavy nuclei, etc. Recent investigations on new effective interactions, the density dependence of the interaction strengthes, the RMF theory on the Woods-Saxon basis, the single particle resonant states, and the resonant BCS (rBCS) method for the pairing correlation, etc. are also presented in some details.
description: 79 pages. Prog. Part. Nucl. Phys. (2005) in press
Development of a general-purpose machine-learning interatomic potential for aluminum by the physically-informed neural network method
Creators: name: Pun, G. P. Purja
name: Yamakov, V.
name: Hickman, J.
name: Glaessgen, E. H.
name: Mishin, Y.
Publisher: name: arXiv
Year: 2020
Subjects: subject: Computational Physics (physics.comp-ph)
subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: Abstract Interatomic potentials constitute the key component of large-scale atomistic simulations of materials. The recently proposed physically-informed neural network (PINN) method combines a high-dimensional regression implemented by an artificial neural network with a physics-based bond-order interatomic potential applicable to both metals and nonmetals. In this paper, we present a modified version of the PINN method that accelerates the potential training process and further improves the transferability of PINN potentials to unknown atomic environments. As an application, a modified PINN potential for Al has been developed by training on a large database of electronic structure calculations. The potential reproduces the reference first-principles energies within 2.6 meV per atom and accurately predicts a wide spectrum of physical properties of Al. Such properties include, but are not limited to, lattice dynamics, thermal expansion, energies of point and extended defects, the melting temperature, the structure and dynamic properties of liquid Al, the surface tensions of the liquid surface and the solid-liquid interface, and the nucleation and growth of a grain boundary crack. Computational efficiency of PINN potentials is also discussed.
话本教学模式运用于线上汉语课堂的成效
Creators: name: LIU, Hsin-Yi
Publisher: name: CHUN - Chinesisch-Unterricht
Year: 2024

description: 本研究中实验设置分为控制组和实验组两组汉语零起点学习者，两组课程由同一教师、同一线上会议软件平台进行线上教学。针对学生学习成效与课后回馈，以及教师教学与备课情形收集相关数据，最终比较两组课堂的教学成效和学生学习表现。本文具体呈现控制组与实验组对比实证研究方法与结果，旨在以所收集的结果数据展现话本教学模式运用于线上初级汉语教学课程中的成效，并提供汉语教学在新冠疫情中一个有效且实际的教学实践模式。本研究实验的各项数据结果证实话本教学模式的运用，在教师欠缺实际汉语教学经验，而且尚未熟练各种线上教学技能的前提下，能够有效提升汉语作为第二语言学科零起点初学者对于初级内容的学习成效﹑提高课堂教学效率﹑大幅降低教师备课时间与教学精神压力。
description: CHUN - Chinesisch-Unterricht, Bd. 36 (2021): CHUN - Chinesischunterricht
Measuring Large Scale Space Perception in Literary Texts
Creators: name: Rossi, Paolo
Publisher: name: arXiv
Year: 2006
Subjects: subject: Statistics Theory (math.ST)
subject: FOS: Mathematics

description: The center and radius of perception associated with a written text are defined, and algorithms for their computation are presented. Indicators for anisotropy in large scale space perception are introduced. The relevance of these notions for the analysis of literary and historical records is briefly discussed and illustrated with an example taken from medieval historiography.
description: 8 pages, 1 figure
Tetrahedron and 3D reflection equation from PBW bases of the nilpotent subalgebra of quantum superalgebras
Creators: name: Yoneyama, Akihito
Publisher: name: arXiv
Year: 2020
Subjects: subject: Mathematical Physics (math-ph)
subject: Quantum Algebra (math.QA)
subject: Exactly Solvable and Integrable Systems (nlin.SI)
subject: FOS: Physical sciences
subject: FOS: Mathematics
subject: 17B37, 17B80

description: In this paper, we study transition matrices of PBW bases of the nilpotent subalgebra of quantum superalgebras associated with all possible Dynkin diagrams of type A and B in the case of rank 2 and 3, and examine relationships with three-dimensional (3D) integrability. We obtain new solutions to the Zamolodchikov tetrahedron equation via type A and the 3D reflection equation via type B, where the latter equation was proposed by Isaev and Kulish as a 3D analog of the reflection equation of Cherednik. As a by-product of our approach, the Bazhanov-Sergeev solution to the Zamolodchikov tetrahedron equation is characterized as the transition matrix for a particular case of type A, which clarifies an algebraic origin of it. Our work is inspired by the recent developments connecting transition matrices for quantum non-super algebras with intertwiners of irreducible representations of quantum coordinate rings. We also discuss the crystal limit of transition matrices, which gives a super analog of transition maps of Lusztig's parametrizations of the canonical basis.
description: 51 pages, minor corrections
Fabrizio Conca, La mia Signora. Storia di un amore bianconero
Creators: name: Vallorani, Nicoletta
Publisher: name: Università degli  Studi di Milano
Year: 2015

description: Fabrizio Conca, La mia Signora. Storia di un amore bianconero (Milano, Schena Editore ISBN 978-88-6806-089-3) di Nicoletta ValloraniFabrizio Conca, La mia Signora. Storia di un amore bianconero (Milano, Schena Editore ISBN 978-88-6806-089-3) di Nicoletta Vallorani
description: Altre Modernità, No 14 (2015): Giocarsi l’identità: sport  e culture, il locale e il globale
Gas flow hydrodynamics in an oxygen delignification retention tower
Creators: name: Pineault, Isabelle
Publisher: name: University of British Columbia
Year: 2009

description: Gas flow hydrodynamics were characterized as a function of pulp suspension concentration in a laboratory-scale residence tower. Three kraft pulps were studied: never-dried brown stock (kappa 33), a fully bleached kraft pulp (88-89% brightness) that never had been dried, and a dried and reslurried fully bleached kraft pulp (88-89% brightness). The following experiments were performed to charaterize gas flow in pulp retention towers. First, gas flow in a narrow rectangular tower was characterised as a function of suspension mass concentration by calculating the bubble rising velocity. These results were compared with bubble rising velocity measurement made in a pilot-scale column having a L/D ratio of 6.5:1 (inside diameter of27.94 cm).. The same column was used to measure gas holdup with both the gas disengagement technique [Daly et al., 1992] and measurements of the density variation method along the column height. Finally, mass transfer was evaluated in a small laboratory-scale column ( L/D = 4.1:1) using a dissolved oxygen probe. The main results of these experiments are as follows. First is was found that at medium pulp consistency, there are no bubbles formed in the tower due to the lack o f free water. Second, at pulp consistencies higher than 5 %, gas is trapped in the fibre network, which increases considerably the gas holdup. Furthermore, this gas holdup is not influenced by the gas flow rate. Third, the bubble size at low consistencies is influenced by the air flow rate as well as the pulp consistency present in the column. Fourth, the type of pulp used did not have a great influence on the gas holdup in the pilot-scale column. Finally, mass transfer occurs in the laboratory-scale column, with kL a values in the same range as the those reported in bubble columns.
Emergency online Chinese language teaching at the tertiary level
Creators: name: LIN, Chin-Hui
Publisher: name: CHUN - Chinesischunterricht
Year: 2024

description: Based on an online survey of 42 university Chinese language teachers from 19 higher educational institutions in Austria, Germany, and Switzerland, this study aims to document and examine teachers’ experiences and perceptions of online teaching during the first emergency online semester (spring to summer 2020). The scope of investigation includes digital tool use before and during the pandemic, problems teachers encountered in a remote setting, what they regarded as positive and negative about online teaching, and whether their online teaching experiences will influence their future teaching. Furthermore, challenges of online assessments and handwriting skill teaching during this semester will also be discussed.
description: CHUN - Chinesischunterricht, Bd. 36 (2021): CHUN - Chinesischunterricht
Regularization of the Nambu-Jona Lasinio model under a uniform magnetic field and the role of the anomalous magnetic moments
Creators: name: Aguirre, R. M.
Publisher: name: arXiv
Year: 2020
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: Nuclear Theory (nucl-th)
subject: FOS: Physical sciences

description: The vacuum contribution to quark matter under a uniform magnetic field within the SU(3) version of the Nambu and Jona-Lasinio model is studied. The standard regularization procedure is examined and a new prescription is proposed. For this purpose analytic regularization and a subtraction scheme are used to deal with divergencies depending on the magnetic intensity. This scheme is combined with the standard three momentum cutoff recipe, and reduces to it for vanishing magnetic intensity. Furthermore, the effects of a direct coupling between the anomalous magnetic moments of the quarks and the magnetic field is considered. Single particle properties as well as bulk thermodynamical quantities are studied for a configuration of matter found in neutron stars. A wide range of baryonic densities and magnetic intensities are examined at zero temperature.
description: Major revision
FENOMENOLOGIA DEL RIUTILIZZO: DANTE IN M. PEARL E S. MEREDITH
Creators: name: Gelmi, Alberto
Publisher: name: Università degli Studi di Milano
Year: 2015
Subjects: Inferno; Pearl; Meredith; cinema

description: Starting with some brief remarks by Cesarani, the essay focuses on two recent American re-adaptations of Dante’s masterpiece, i.e. M. Pearl’s novel The Dante club and Dante’s inferno, an independent movie by S. Meredith. In each work, the author traces the effectiveness of the pattern of contrappasso in diegetic terms, along with their implicit political narratives.
description: Carte romanze, Vol 3, No 2 (2015)
Ultra low-mass star and substellar formation in sigma Orionis
Creators: name: Caballero, J. A.
Publisher: name: arXiv
Year: 2005
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: The nearby young sigma Orionis cluster (~360 pc, ~3 Ma) is becoming one of the most important regions for the study of ultra low-mass star formation and its extension down to the mass regimes of the brown dwarfs and planetary-mass objects. Here, I introduce the sigma Orionis cluster and present three studies that the JOVIAN group is developing: a pilot programme of near-infrared adaptive-optics imaging, intermediate-resolution optical spectroscopy of a large sample of stars of the cluster and a study of the mass function down to the planetary-mass domain. This paper is a summary of the content of four posters that I presented in the Ultra low-mass star formation and evolution Workshop, as single author or on behalf of different collaborations.
description: 4 pages, 4 figures. Proceeding at the IAC-TNG Workshop on Ultra low-mass star formation and evolution, 28 June - 1 July 2005, La Palma, Canary Islands, Spain. Accepted for publication in Astron. Nachr
Chinesisch sprechen, schreiben, forschen?
Creators: name: Guder, Andreas
name: Burckhardt, Vincent
Publisher: name: CHUN – Chinesischunterricht
Year: 2024

description: Der vorliegende Beitrag dokumentiert die Ergebnisse einer umfangreichen Befragung der chinawissenschaftlichen Institute im deutschsprachigen Raum zur Sprachausbildung Chinesisch. Erfragt wurden die angebotenen Studiengänge, deren angestrebte Zielkompetenzen, der Umfang der Chinesischkurse, Anzahl der Studierenden, Anzahl und Hintergrund der Lehrkräfte, verwendete Lehrwerke sowie Informationen über den via ECTS veranschlagten Workload in Relation zum Umfang des Sprachlehrangebots. Darüber hinaus wurden auch die Sprachausbildung im Rahmen von chinawissenschaftlichen Masterstudiengängen, die Integration von Auslandssemestern, die Relevanz standardisierter Prüfungen aus der VR China und Taiwan sowie die Ausbildung in Vormodernem/Klassischem Chinesisch erfasst. Im Ergebnis zeigt sich, dass die im Rahmen einer chinawissenschaftlichen Ausbildung als selbstverständlich betrachtete akademische Sprachausbildung im Chinesischen eine außerordentlich komplexe Aufgabe ist, die auch im Rahmen eines dreijährigen Bachelorstudiums keinesfalls als abgeschlossen betrachtet werden kann und die an vielen Instituten nach wie vor kapazitär unterausgestattet ist.
description: CHUN – Chinesischunterricht, Bd. 36 (2021): CHUN - Chinesischunterricht
Telecommunications regulatory reform in small island developing states : the impact of WTO's telecommunication commitment
Creators: name: Ofa, Siope Vakataki
Publisher: name: The Australian National University
Year: 2010
Subjects: subject: HE8620.7.O33 2010
subject: Telecommunication policy Pacific Area
subject: World Trade Organization Developing countries

description: Why does the government of one small island developing state produce credible telecommunications reform policies while another cannot? While telecommunications reform (competition, privatization and establishment of an independent regulator) is found to enhance the sector's performance and eventual economic growth in developing countries, it is not clear why several small island developing state governments have hindered, amended or reversed pre-announced telecommunications reform policies. The credibility of telecommunications reform therefore demands an in-depth examination, in particular, to examine the impact of the multilateral trade agreement (World Trade Organization, WTO), bilateral investment treaties and independent regulators on the credibility of domestic telecommunications reform in small island developing states. A mixed-method research design was adopted through comparative case study analyses of Fiji, Papua New Guinea, Samoa, Tonga and Vanuatu. Sixty-four semistructured interviews of key telecommunications stakeholders were conducted in the capital city of each case study from June to December 2008. Further, multiple regression analyses based on a panel data of 160 developing countries (including 26 small island developing states) covering the period 1995-2006 were undertaken to triangulate the evidence from the fieldwork. Contrary to conventional findings from the telecommunications and bilateral investment treaty literatures in developing countries, the research found that the establishment of an independent regulator and signatory to Bilateral Investment Treaties instills less pronounced credibility for telecommunications reform in small island developing states, while WTO telecommunications commitment instill stronger credibility. The recent telecommunications reform in the Pacific showed the vulnerability of independent regulators to regulatory capture. The main findings of the research emphasize the importance of considering the disadvantages of smallness when adopting the successful telecommunications policy experiences from larger developing economies into the context of a small island developing state.
Il manoscritto ambrosiano del «Roman de Troie» (D55 sup.): nuove ipotesi sulla sua produzione e circolazione
Creators: name: Orobello, Giuseppina
Publisher: name: Università degli Studi di Milano
Year: 2015
Subjects: Benoît de Sainte-Maure, Roman de Troie, Plombeolo de’ Plombeoli, miniatura, scripta, Antiochia, Venezia, Oltremare

description: Nel presente contributo vengono esposte nuove ipotesi circa la provenienza e la storia antica del manoscritto ambrosiano del Roman de Troie (Milano, Biblioteca Ambrosiana, D55sup) formulate dopo un’attenta analisi del codice stesso e di numerose fonti d’archivio. In particolare nuovi spunti vengono offerti dal ritrovamento di un documento autografo di Plombeolo de’ Plombeoli, autore della nota di possesso a c. 196v, e dalla scoperta della firma erasa di Jacopo Plombeoli, finora mai notata, all’interno del manoscritto. Grazie allo studio delle miniature e al confronto di queste con altri apparati decorativi si offre una nuova ipotesi circa il luogo di produzione del manufatto, che andrebbe collocato in area crociata e più precisamente ad Antiochia.
description: Carte romanze, Vol 3, No 2 (2015)
Quantum analogue of the spin-flop transition for a spin pair
Creators: name: Ivanov, B. A.
name: Kireev, V. E.
Publisher: name: arXiv
Year: 2005
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: Quantum (step-like) magnetization curves are studies for a spin pair with antiferromagnetic coupling in the presence of a magnetic field parallel to the easy axis of the magnetic anisotropy. The consideration is done both analytically and numerically for a wide range of the anisotropy constants and spins up to $S \gtrsim 100$. Depending on the origin of the anisotropy (exchange or single-ion), the magnetization curve can demonstrate the jumps more than unity and the concentration of the unit jumps in a narrow range of the field. We also point the region of the problem parameters, where the behavior is quasiclassical for $S = 5$, and where system is substantially quantum in the limit $S \to \infty$.
description: 5 pages, 5 figures
Erinnerungsblätter Kurt Meyer 1889 -1914
Creators: name: Meyer, Kurt
Publisher: name: Zenodo
Year: 2019
Subjects: world war 1, daily life of German adolescent (officer family), soldier of Hannover regiment FR 73 - later on famous by Ernst Juenger "In Stahlgewittern", letters.

description: Letters of a German soldier (died in action as a second lieutenant of Hannover regiment, later on famous by Ernst Juenger), to his parents - father officer, too. From last year at school to his end. Details of typical daily life, but also of personal tragedy. Old photographs, explanations.
Feedback from quasars in star-forming galaxies and the triggering of massive galactic winds
Creators: name: Monaco, P.
name: Fontanot, F.
Publisher: name: arXiv
Year: 2005
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: The shining of quasars is a likely trigger of massive galatic winds, able to remove most ISM from a star-forming spheroid. However, the mechanism responsible for the deposition of energy into the ISM is still unclear. Starting from a model for feedback in galaxy formation with a two-phase medium (Monaco 2004a), we propose that the perturbation induced by radiative heating from a quasar on the ISM triggers a critical change of feedback regime. In the feedback model, SNRs expanding in the hot and pressurized phase of a star-forming spheroid tipically become pressure-confined before the hot interior gas is able to cool. Whenever the evaporation flow due to radiative heating of the quasar is significant with respect to the star-formation rate, the SNRs reach the point where their interior gas cools before being confined, forming a thick cold shell. We show that in this conditions the shells percolate into a super-shell of cold gas that sweeps the whole galaxy. Radiation pressure then pushes the shell out of the galaxy. This self-limiting mechanism leads to a correlation between black hole and bulge masses. The insertion of a motivated wind trigger criterion in a hierarchical galaxy formation model shows however that winds are not necessary to obtain a good black hole--bulge correlation. In absence of winds, good results are obtained if the mechanism responsible for the creation of a reservoir of low-angular momentum gas (able to accrete onto the black hole) deposits mass at a rate proportional to the star-formation rate. Using a novel galaxy formation model, we show under which conditions black hole masses are self-limited by the wind mechanism described above, and outline the possible observational consequences of this self-limitation. [Abridged]
description: 14 pages, 7 ps figures included, uses mn2e.cls. MNRAS, in press
Trace dynamics and division algebras: towards quantum gravity and unification
Creators: name: Singh, Tejinder P.
Publisher: name: arXiv
Year: 2020
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: General Relativity and Quantum Cosmology (gr-qc)
subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: We have recently proposed a Lagrangian in trace dynamics at the Planck scale, for unification of gravitation, Yang-Mills fields, and fermions. Dynamical variables are described by odd-grade (fermionic) and even-grade (bosonic) Grassmann matrices. Evolution takes place in Connes time. At energies much lower than Planck scale, trace dynamics reduces to quantum field theory. In the present paper we explain that the correct understanding of spin requires us to formulate the theory in 8-D octonionic space. The automorphisms of the octonion algebra, which belong to the smallest exceptional Lie group $G_2$, replace space-time diffeomorphisms and internal gauge transformations, bringing them under a common unified fold. Building on earlier work by other researchers on division algebras, we propose the Lorentz-weak unification at the Planck scale, the symmetry group being the stabiliser group of the quaternions inside the octonions. This is one of the two maximal subgroups of $G_2$, the other one being $SU(3)$, the element preserver group of octonions. This latter group, coupled with $U(1)_{em}$, describes the electro-colour symmetry, as shown earlier by Furey. We predict a new massless spin one boson [the Lorentz boson] which should be looked for in experiments. Our Lagrangian correctly describes three fermion generations, through three copies of the group $G_2$, embedded in the exceptional Lie group $F_4$. This is the unification group for the four fundamental interactions, and it also happens to be the automorphism group of the exceptional Jordan algebra. Gravitation is shown to be an emergent classical phenomenon. Whereas at the Planck scale, there is present a quantised version of the Lorentz symmetry, mediated by the Lorentz boson. We argue that at sub-Planck scales, the self-adjoint part of the octonionic trace dynamics bears a relationship with string theory in eleven dimensions.
description: v4. 70 pages, 4 figures, references updated, published online in Zeitschrift fur Naturforschung A
Frustrated phase separation in two-dimensional charged systems
Creators: name: Ortix, C.
name: Lorenzana, J.
name: Di Castro, C.
Publisher: name: arXiv
Year: 2005
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: We study phase separation frustrated by the long-range Coulomb interaction in two dimensional electronic systems with emphasys in the case of a metallic and an insulating phase. We find that two-dimensional systems are more prone to mesoscopic frustrated phase separation than the three dimensional ones.
description: 15 pages, 11 figures
Ultracool Dwarfs in deep extragalactic surveys using the Virtual Observatory: ALHAMBRA and COSMOS
Creators: name: Solano, E.
name: Gálvez-Ortiz, M. C.
name: Martín, E. L.
name: Muñoz, I. M. Gómez
name: Rodrigo, C.
name: Burgasser, A. J.
name: Lodieu, N.
name: Béjar, V. J. S.
name: Huélamo, N.
name: Morales-Calderón, M.
name: Bouy, H.
Publisher: name: arXiv
Year: 2020
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: Ultracool dwarfs encompass a wide variety of compact stellar-like objects with spectra classified as late-M, L, T and Y. Most of them have been discovered using wide-field imaging surveys. The Virtual Observatory has proven to be of great utility to efficiently exploit these astronomical resources. We aim to validate a Virtual Observatory methodology designed to discover and characterize ultracool dwarfs in deep extragalactic surveys like ALHAMBRA and COSMOS. Three complementary searches based on parallaxes, proper motions and colours, respectively were carried out. A total of 897 candidate ultracool dwarfs were found, with only 16 previously reported in SIMBAD. Most of the new UCDs reported here are likely late-M and L dwarfs because of the limitations imposed by the utilization of optical ($Gaia$ DR2 and r-band) data. We complement ALHAMBRA and COSMOS photometry with other catalogues in the optical and infrared using VOSA, a Virtual Observatory tool that estimates effective temperatures from the spectral energy distribution fitting to collections of theoretical models. The agreement between the number of UCDs found in the COSMOS field and theoretical estimations together with the low false negative rate (known UCDs not discovered in our search) validates the methodology proposed in this work, which will be used in the forthcoming wide and deep surveys provided by the Euclid space mission. Simulations of Euclid number counts for UCDs detectable in different photometric passbands are presented for a wide survey area of 15,000 square degrees, and the limitations of applicability of Euclid data to detect UCDs using the methods employed in this paper are discussed.
Optimized Monte Carlo Method for glasses
Creators: name: Fernandez, L. A.
name: Martin-Mayor, V.
name: Verrocchio, P.
Publisher: name: arXiv
Year: 2006
Subjects: subject: Statistical Mechanics (cond-mat.stat-mech)
subject: FOS: Physical sciences

description: A new Monte Carlo algorithm is introduced for the simulation of supercooled liquids and glass formers, and tested in two model glasses. The algorithm is shown to thermalize well below the Mode Coupling temperature and to outperform other optimized Monte Carlo methods. Using the algorithm, we obtain finite size effects in the specific heat. This effect points to the existence of a large correlation length measurable in equal time correlation functions.
description: Proceedings of "X International workshop on Disordered Systems" held in Molveno (Italy), March 2006
Computer-assisted proof for the stationary solution existence of the Navier-Stokes equation over 3D domains
Creators: name: Liu, Xuefeng
name: Nakao, Mitsuhiro T.
name: Oishi, Shin'ichi
Publisher: name: arXiv
Year: 2021
Subjects: subject: Numerical Analysis (math.NA)
subject: FOS: Mathematics
subject: 35Q30, 65M60

description: This paper proposes a computer-assisted solution existence verification method for the stationary Navier-Stokes equation over general 3D domains. The proposed method verifies that the exact solution as the fixed point of the Newton iteration exists around the approximate solution through rigorous computation and error estimation. The explicit values of quantities required by applying the fixed point theorem are obtained by utilizing newly developed quantitative error estimation for finite element solutions to boundary value problems and eigenvalue problems of the Stokes equation.
description: 1 figures
Time series analysis of voidage signals in a bubbling fluidised bed
Creators: name: Shen, Chengyu
Publisher: name: University of British Columbia
Year: 2009

description: The dynamics of voidage signals in bubbling fluidised beds are investigated both experimentally and numerically. Experimental voidage signals were obtained by using an optical fibre probe at different positions in a freely bubbling fluidised bed of diameter of 150 mm. Numerical simulated voidage signals were also predicted using the Cliff and Grace bubble coalescence model. Analysis of the experimental signals demonstrates that deterministic chaos can arise in bubbling fluidised beds. Voidage signals collected at different geometrical positions indicate that bubble size and frequency influence the chaotic characteristics of the voidage signals. In the bottom, the voidage signals were generally more chaotic than in the top section, while near the bed surface, with voidage signals becoming less chaotic because of the bubble coalescence which has already occurred. The numerical study used the three-dimensional version of the bubble coalescence model to simulate optical probe signals in a gas-solid fluidised bed. These predictions demonstrate that deterministic chaos can arise from non-linear bubble interactions in bubbling fluidised beds. It is found that both bubble frequency and initial bubble size influence the chaotic characteristics of the simulated voidage fraction signal, with bubble frequency having a stronger effect than the initial bubble size.
Magnetic Ergostars, Jet Formation and Gamma-Ray Bursts: Ergoregions versus Horizons
Creators: name: Ruiz, Milton
name: Tsokaros, Antonios
name: Shapiro, Stuart L.
name: Nelli, Kyle C.
name: Qunell, Sam
Publisher: name: arXiv
Year: 2020
Subjects: subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: We perform the first fully general relativistic, magnetohydrodynamic simulations of dynamically stable hypermassive neutron stars with and without ergoregions to assess the impact of ergoregions on launching magnetically--driven outflows. The hypermassive neutron stars are modeled by a compressible and causal equation of state and are initially endowed with a dipolar magnetic field extending from the stellar interior into its exterior. We find that, after a few Alfvén times, magnetic field lines in the ergostar (star that contains ergoregions) and the normal star have been tightly wound in both cases into a helical funnel within which matter begins to flow outward. The maximum Lorentz factor in the outflow is $Γ_L \sim 2.5$, while the force-free parameter holds at $B^2/8πρ_0\lesssim 10$. These values are incompatible with highly relativistic, magnetically-driven outflows (jets) and short $γ$-ray bursts. We compare these results with those of a spinning black hole surrounded by a magnetized, massless accretion disk that launches a bona fide jet. Our simulations suggest that the Blandford-Znajek mechanism for launching relativistic jets only operates when a black hole is present, though the Poynting luminosity in all cases is comparable. Therefore, one cannot distinguish a magnetized, accreting black hole from a magnetized hypermassive neutron star in the so-called mass-gap based solely on the value of the observed Poynting luminosity. These results complement our previous studies of supramassive remnants and suggest that it would be challenging for either normal neutron stars or ergostars in a hypermassive state to be the progenitors of short $γ$-ray bursts.
description: 7 pages, 3 figures. Matches published version
Supplementary document for Metasurface-integrated Silicon Nitride Waveguides for Holography with Full Polarization Control - 7403864.pdf
Creators: name: Lin, Yuhang
name: liang, zhouxin
name: Li, Jiaqi
name: gu, xin
name: wang, jieyang
name: Zhu, Zhaoxiang
name: Chen, Yujie
Publisher: name: Optica Publishing Group
Year: 2025
Subjects: Uncategorized

description: supplemental materials of: Metasurface-integrated Silicon Nitride Waveguides for Holography with Full Polarization Control
Crystal-field level inversion in lightly Mn-doped Sr3Ru2O7
Creators: name: Hossain, M. A.
name: Hu, Z.
name: Haverkort, M. W.
name: Burnus, T.
name: Chang, C. F.
name: Klein, S.
name: Denlinger, J. D.
name: Lin, H. -J.
name: Chen, C. T.
name: Mathieu, R.
name: Kaneko, Y.
name: Tokura, Y.
name: Satow, S.
name: Yoshida, Y.
name: Takagi, H.
name: Tanaka, A.
name: Elfimov, I. S.
name: Sawatzky, G. A.
name: Tjeng, L. H.
name: Damascelli, A.
Publisher: name: arXiv
Year: 2008
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: Sr3(Ru1-xMnx)2O7, in which 4d-Ru is substituted by the more localized 3d-Mn, is studied by x-ray dichroism and spin-resolved density functional theory. We find that Mn impurities do not exhibit the same 4+ valence of Ru, but act as 3+ acceptors; the extra eg electron occupies the in-plane 3dx2-y2 orbital instead of the expected out-of-plane 3d3z2-r2. We propose that the 3d-4d interplay, via the ligand oxygen orbitals, is responsible for this crystal-field level inversion and the material's transition to an antiferromagnetic, possibly orbitally-ordered, low-temperature state.
description: A high-resolution version can be found at http://www.physics.ubc.ca/~quantmat/ARPES/PUBLICATIONS/Articles/MnSr3Ru2O7_XAS.pdf
Buket Altınoba; Die Istanbuler Kunstakademie von ihrer Gründung bis heute. Moderne Kunst, Nationenbildung und Kulturtransfer in der Türkei
Creators: name: Karaca, Banu
Publisher: name: Journal für Kunstgeschichte
Year: 2024

description: Rezension zu: Buket Altınoba; Die Istanbuler Kunstakademie von ihrer Gründung bis heute. Moderne Kunst, Nationenbildung und Kulturtransfer in der Türkei; Berlin: Gebr. Mann Verlag 2016; 446 S , 18 farb u 162 s/w-Abb ; ISBN 978-3-7861-2731-4
description: Journal für Kunstgeschichte, Bd. 24 Nr. 1 (2020): Journal für Kunstgeschichte
End-to-End Deep Structured Models for Drawing Crosswalks
Creators: name: Liang, Justin
name: Urtasun, Raquel
Publisher: name: arXiv
Year: 2020
Subjects: subject: Computer Vision and Pattern Recognition (cs.CV)
subject: FOS: Computer and information sciences

description: In this paper we address the problem of detecting crosswalks from LiDAR and camera imagery. Towards this goal, given multiple LiDAR sweeps and the corresponding imagery, we project both inputs onto the ground surface to produce a top down view of the scene. We then leverage convolutional neural networks to extract semantic cues about the location of the crosswalks. These are then used in combination with road centerlines from freely available maps (e.g., OpenStreetMaps) to solve a structured optimization problem which draws the final crosswalk boundaries. Our experiments over crosswalks in a large city area show that 96.6% automation can be achieved.
Mechanisms of dexamethasone-induced hypertension
Creators: name: Ong, Sharon Leng Hong
Publisher: name: The Australian National University
Year: 2010
Subjects: subject: RC685.H8 O54 2010
subject: Adrenocortical hormones Physiological effect
subject: Hypertension

description: Adrenocortical steroids with predominant glucocorticoid activity, both naturally-occurring and synthetic, have long been recognised as a cause of hypertension. Models of glucocorticoid-induced hypertension (GC-HT) in the rat such as adrenocorticotrophic hormone-induced hypertension (ACTH-HT) and dexamethasone-induced hypertension (DEX-HT) are well-characterised, although the mechanisms contributing to hypertension are less well-understood. Previous studies have shown that ACTH-HT is associated with increased renal vascular resistance, nitric oxide deficiency and oxidative stress. The latter was shown to be linked to the NAD(P)H oxidase but not the xanthine oxidase pathways. As there were proven differences in the pathogenesis of these two models of GC-HT, mechanisms of ACTH-HT cannot be assumed in DEX-HT. The main aim of this project was to evaluate the mechanisms of DEX-HT, namely the haemodynamic mechanisms and the role of oxidative stress. The role of {u03B2}-adrenergic receptor blockade was also evaluated. In some studies, experiments on both dexamethasone (DEX)- and ACTH-HT were conducted for comparison. DEX (10-20 {u03BC}g/rat/day) raised blood pressure in rats without significant metabolic side effects such as precipitous weight loss. The haemodynamic experiments showed that DEX-HT in rats was associated with increased total peripheral resistance and decreased total peripheral conductance, although these were not critical features for the production of DEX-HT. This project showed that the xanthine oxidase pathway and mitochondria were not the major source of superoxide contributing to oxidative stress in DEX-HT. Mitochondrial superoxide, evaluated using a novel mitochondrial specific fluorogenic probe (mito-hydroethidine) via flow cytometry designed for this purpose, was also shown in this project not to playa major role in ACTH-HT in rats. The arachidonic acid metabolite 20-hydroxyeicosatetraenoic acid, which is increased by nitric oxide deficiency and known to cause oxidative stress and exacerbate nitric oxide deficiency, also did not playa significant role in the pathogenesis of DEX-HT. Propranolol, both a beta adrenergic receptor blocker and lipid peroxidation inhibitor, was not effective in preventing GC-HT. In conclusion, an increase in total peripheral resistance and nitric oxide-redox imbalance appear to be features of DEX-HT in the rat although the exact mechanism by which DEX raises blood pressure in human remains incompletely understood. Further studies exploring 1) the differences in mechanisms between naturally-occuring and synthetic glucocorticoids and 2) the relevance of oxidative stress and nitric oxide-redox imbalance in human GC-HT are important in advancing our understanding in this form of hypertension.
Generating quantum resources through measurement and control
Creators: name: Stevenson, Robin
Publisher: name: The Australian National University
Year: 2013
Subjects: subject: Quantum measure theory
subject: Control theory
subject: Quantum entanglement

description: The quantum resources of entanglement and single photons are key to a range of quantum applications. These resources are challenging to produce cleanly and efficiently. This thesis investigates and improves methods of producing entanglement and single photons using measurement and control. To robustly produce entanglement, this thesis extends work by Carvalho et al., who developed a method for creating an entangled state of two atoms. This is done by coupling the atoms to a damped cavity, and using measurement of the output of the cavity to trigger a feedback pulse on the atoms. The robustness of this scheme against imperfect localisation of the two atoms is tested in this thesis, and limits are placed on the size of a trap that will still allow an entangled state to be produced. Additionally, using three-level (Lambda configuration) atoms slows the rate at which the system evolves, allowing more time for measurement and feedback to be applied, though it does not counteract the influence of spontaneous emission. In extending this work to multiple atoms we found that the system rapidly becomes more complex, and we developed a strategy for choosing a feedback pulse that stabilises a specific, highly entangled steady state of multiple particles. In addition to this general strategy, we developed a local and separable feedback for generating entanglement in a four-partite system. This thesis also investigates the production of single photons through the rephased amplified spontaneous emission (RASE) protocol. This protocol offers the promise of a stream of precisely shaped single photons, though it is plagued by efficiency issues. We develop a model of RASE and show that it overcomes the trade-off between efficiency and photon spacing by using different optical depths for the amplified spontaneous emission (ASE) preparation of the ensemble, and the RASE emission of single photons. By tailoring the density profile of the ensemble to mode-match the RASE emission of a single photon, we also able to eliminate reabsorption of the emitted photon, which would otherwise have limited the efficiency to 70%.