cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Canadian evaluation of a Mexican mining venture and the next investment step
Creators: name: Bach, Geoffrey D.,
Publisher: name: University of British Columbia
Year: 2010

description: This study evaluates a minority interest in a silver orebody in Zacatecas, Mexico, leading to a decision in mid 1979 by a Canadian mining company, whether to sell, hold or develop the orebody into a silver mine on a joint venture basis. The framework employed in the evaluation emphasizes the importance to mining companies of exploration to identify mineral orebodies, and strives to assess the Canadian miners' view of the political and economic circumstances in Mexico as they may affect a long-term mine investment in that country by a Canadian corporation. Alternative methods of evaluating an orebody are established and reviewed in conjunction with the selection of what has value to whom, and what influences the value. Success of the Canadian mining investment in Mexico depends on the relationships between the three joint venture partners in addition to the existence of an identified orebody ready for development. Before measurement of the value of the minority interest in the orebody is attempted, an examination is made of the needs of partners, the selection of partners and the relationships between the partners to the joint venture. Measurement of the value of the minority interest is based on a feasibility study prepared in 1975 and up-dated by the writer to early 1979 conditions. Production data, revenue forecasts and mine costs of construction and subsequent operations are presented and analysed to provide an overview of the financial aspects of the potential mine. Valuation of the minority interest in the orebody is achieved after determining mine cash flow forecasts, net earnings forecasts and forecast social benefits and costs to Mexico. The conclusions of the study are that the Canadian's investment has a value in the range US $3 100 000 to US $3 900 000 and that the orebody will continue to be held until circumstances allow improved returns to the owners of the orebody.
title: Front Matter, Table of Contents, Preface, Conference Organization
Creators: name: Kabanets, Valentine
Publisher: name: Schloss Dagstuhl – Leibniz-Zentrum für Informatik
Year: 2021
Subjects: subject: Front Matter
subject: Table of Contents
subject: Preface
subject: Conference Organization
subject: Theory of computation

description: Front Matter, Table of Contents, Preface, Conference Organization
description: LIPIcs, Vol. 200, 36th Computational Complexity Conference (CCC 2021), pages 0:i-0:xvi
Graphene in curved Snyder space
Creators: name: Hamil, B.
name: Aounallah, H.
name: Lütfüoğlu, B. C.
Publisher: name: arXiv
Year: 2021
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: The Snyder-de Sitter (SdS) model which is invariant under the action of the de Sitter group, is an example of a noncommutative spacetime with three fundamental scales. In this paper, we considered the massless Dirac fermions in graphene layer in a curved Snyder spacetime which are subjected to an external magnetic field. We employed representation in the momentum space to derive the energy eigenvalues and the eigenfunctions of the system. Then, we used the deduced energy function obtaining the internal energy, heat capacity, and entropy functions. We investigated the role of the fundamental scales on these thermal quantities of the graphene layer. We found that the effect of the SdS model on the thermodynamic properties is significant.
description: 11 pages, 4 figures
The $K(π,1)$ conjecture and acylindrical hyperbolicity for relatively extra-large Artin groups
Creators: name: Goldman, Katherine
Publisher: name: arXiv
Year: 2022
Subjects: subject: Group Theory (math.GR)
subject: Metric Geometry (math.MG)
subject: FOS: Mathematics
subject: 20F36 (Primary) 20F65, 57M60 (Secondary)

description: Let $A_Γ$ be an Artin group with defining graph $Γ$. We introduce the notion of $A_Γ$ being extra-large relative to a family of arbitrary parabolic subgroups. This generalizes a related notion of $A_Γ$ being extra-large relative to two parabolic subgroups, one of which is always large type. Under this new condition, we show that $A_Γ$ satisfies the $K(π,1)$ conjecture whenever each of the distinguished subgroups do. In addition, we show that $A_Γ$ is acylindrically hyperbolic under only mild conditions.
description: 16 pages, 11 figures, to be published in Algebraic & Geometric Topology
Linear perturbations of Hyperkahler metrics
Creators: name: Alexandrov, Sergei
name: Pioline, Boris
name: Saueressig, Frank
name: Vandoren, Stefan
Publisher: name: arXiv
Year: 2008
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: Differential Geometry (math.DG)
subject: FOS: Physical sciences
subject: FOS: Mathematics

description: We study general linear perturbations of a class of 4d real-dimensional hyperkahler manifolds obtainable by the (generalized) Legendre transform method. Using twistor methods, we show that deformations can be encoded in a set of holomorphic functions of 2d+1 variables, as opposed to the functions of d+1 variables controlling the unperturbed metric. Such deformations generically break all tri-holomorphic isometries of the unperturbed metric. Geometrically, these functions generate the symplectomorphisms which relate local complex Darboux coordinate systems in different patches of the twistor space. The deformed Kahler potential follows from these data by a Penrose-type transform. As an illustration of our general framework, we determine the leading exponential deviation of the Atiyah-Hitchin manifold away from its negative mass Taub-NUT limit. In a companion paper arXiv:0810.1675, we extend these techniques to quaternionic-Kahler spaces with isometries.
description: 44 pages, 2 figures, uses JHEP3.cls; v4: section 5.3 shortened, matches published version
title: Professional Doctorate in Sport and Exercise Psychology
Creators: name: Bicker, S
Publisher: name: Liverpool John Moores University
Year: 2021

description: Abstract The present portfolio gives account of the research and applied experiences of a Professional Doctorate Candidate at Liverpool John Moores University. Contained within are a range of research and applied works that aim to inform and develop the sport and exercise psychology field. In parallel, the portfolio encompasses the professional development of the primary author as a trainee sport psychologist, and their journey to individuation (McEwan et al., 2019). The portfolio contains three applied case studies and one teaching case study. The consultancy case studies demonstrate a wide range of psychological interventions from a variety of psychological schools. The first case study concerns an acceptance and commitment therapy (ACT) intervention that is rooted in the school of cognitive behavioural psychology. The second is an existential approach to the consultancy that centres around the subjective lived experience of the client. These case studies contain unique outcomes that aim to provide informative and thoughtful implications for both the discipline of sport psychology and sport psychology practitioners. Within the present portfolio is a meta-study that aims to both develop and broaden the present body of organisational psychology literature, and provide insights into sport professionals’ work-life balance, a concept that has become increasingly popular over the years. Two empirical studies, one concerning exercise dependency in CrossFit, and the other, a narrative exploration of athletes’ return to sport following the COVID-19 pandemic, also demonstrate a variety of research skill and competencies required of the candidate. Readers of this portfolio will also gain some insight into the philosophical development of the candidate throughout their professional doctorate enrolment. Ontological and epistemological positionings are examined, challenged, and subsequently evolve throughout the portfolio. In particular, the author demonstrates their development from a positivist/post-positivist to a constructivist paradigm concerning their underpinning philosophical paradigm. This development is also paralleled in their consultancy practice, where the practitioner’s consultancy values move from a practitioner-led, performance focused lens to a person centred, client led consultancy style. This process of individuation is examined through commentary and reflections, where the candidate seeks to understand their values and beliefs and face up to challenges associated in their development.
$α$-clustering effect on flows of direct photons in heavy-ion collisions
Creators: name: Shi, Chen-Zhong
name: Ma, Yu-Gang
Publisher: name: arXiv
Year: 2021
Subjects: subject: Nuclear Theory (nucl-th)
subject: Nuclear Experiment (nucl-ex)
subject: FOS: Physical sciences

description: In this work, we reconstruct the $γ$-photon energy spectrum which is in good agreement with the experimental data of $^{86}$Kr + $^{12}$C at $E/A$ = 44 MeV in the framework of our modified EQMD model. The directed flow and elliptic flow of free protons and direct photons have been investigated by taking $α$-clustering structure of $^{12}$C into account. Comparing with the free proton, the direct photon flows give a clearer information about early stage of nuclear reaction. Difference of collective flows between different configurations of $^{12}$C is observed in this work. This indicates that collective flows of direct photons are sensitive to the initial configuration, therefore the $γ$ bremsstrahlung process might be taken as an alternative probe to investigate $α$-clustering structure in light nucleus from heavy ion collisions at Fermi-energy region.
description: 10 pages, 9 figures
Search for manifestations of spin-torsion coupling
Creators: name: Trukhanova, Mariya Iv.
name: Andreev, Pavel
name: Obukhov, Yuri N.
Publisher: name: arXiv
Year: 2022
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: We investigate the axial vector torsion-spin coupling effects in the framework of the Poincaré gauge theory of gravity with the general Yang-Mills type Lagrangian. The dynamical equations for the ``electric'' and ``magnetic'' components of the torsion field variable are obtained in the general form and it is shown that the helicity density and the spin density of the electromagnetic field appear as the physical sources. The modified Maxwell's equations for the electromagnetic field are derived, and the electromagnetic wave propagation under the action of the uniform homogeneous torsion field is considered. We demonstrate the Faraday effect of rotation of the polarization for such a wave, and establish the strong bound on the possible cosmic axial torsion field from the astrophysical data.
description: 22 pages, 1 figure, Revtex, misprints removed, references updated
The Emergence, Uses and Impacts of Narratives on Migration: State of the Art
Creators: name: Boswell, Christina
name: Smellie, Saskia
name: Maneri, Marcello
name: Pogliano, Andrea
name: Garcés-Mascareñas, Blanca
name: Benet-Martínez, Verónica
name: Güell, Berta
Publisher: name: Zenodo
Year: 2021
Subjects: migration, migration narratives, narratives production, narratives impact

description: This Working Paper provides an overview of social science literature on narratives, with a particular focus on narratives on migration (MiNa). The paper starts by tracing the emergence of the concept of narratives in a range of social sciences (sociology, anthropology, political science, psychology and media studies), and then outlines a working definition of the concept for use in the BRIDGES project.
 We then map key literature about the emergence and sources of narratives; their psychological, social and political functions; and the factors influencing their spread and prevalence. We go on to explore how the concept has been applied to understand the dynamics of mobility, displacement, integration, public attitudes and political mobilisation in migration studies. We examine some of the key themes of the literature in relation to gender, a key dimension of the BRIDGES project, and then set out a number
 of trends that might be expected to shape the content and diffusion of narratives.
title: Digital technologies and artificial intelligence for active aging: A scoping review on smart glasses in promoting the health of older adults
Creators: name: Delgado-Morales, Claudio
name: Iglesias, Juan Jesus García
name: Hueros, Ana Duarte
Publisher: name: OSF Registries
Year: 2025
Subjects: subject: Health Information Technology
subject: Medicine and Health Sciences
subject: Education
subject: Social and Behavioral Sciences
subject: Sociology
subject: FOS: Sociology
subject: Gerontology
subject: Adult and Continuing Education

description: This is a scoping review on the effectiveness and potential benefits of smart glasses, as emerging digital technologies, in promoting active aging among older adults. The review was conducted in accordance with the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) Statement, and the reporting aligns with the updated and extended checklist and guidelines for scoping reviews, PRISMA-ScR.
New leptons with exotic decays: collider limits and dark matter complementarity
Creators: name: Guedes, Guilherme
name: Santiago, José
Publisher: name: arXiv
Year: 2021
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: We describe current and future hadron collider limits on new vector-like leptons with exotic decays. We consider the possibility that, besides standard decays, the new leptons can also decay into a Standard Model charged lepton and a stable particle like a dark photon. To increase their applicability, our results are given in terms of arbitrary branching ratios in the different decay channels. In the case that the dark photon is stable at cosmological scales we discuss the interplay between the dark photon and the vector-like lepton in generating the observed dark matter relic abundance and the complementarity of collider searches and dark matter phenomenology.
description: 31 pages, 21 figures, 3 tables
A localized approach to generalized Turán problems
Creators: name: Kirsch, Rachel
name: Nir, JD
Publisher: name: arXiv
Year: 2023
Subjects: subject: Combinatorics (math.CO)
subject: FOS: Mathematics
subject: 05C35

description: Generalized Turán problems ask for the maximum number of copies of a graph $H$ in an $n$-vertex, $F$-free graph, denoted by ex$(n,H,F)$. We show how to extend the new, localized approach of Bradač, Malec, and Tompkins to generalized Turán problems. We weight the copies of $H$ (typically taking $H=K_t$), instead of the edges, based on the size of the largest clique, path, or star containing the vertices of the copy of $H$, and in each case prove a tight upper bound on the sum of the weights. A consequence of our new localized theorems is an asymptotic determination of ex$(n,H,K_{1,r})$ for every $H$ having at least one dominating vertex and mex$(m,H,K_{1,r})$ for every $H$ having at least two dominating vertices.
description: 25 pages
Molecular mapping of the PDS70 system: No molecular absorption signatures from the forming planet PDS70 b
Creators: name: Cugno, G.
name: Patapis, P.
name: Stolker, T.
name: Quanz, S. P.
name: Boehle, A.
name: Hoeijmakers, H. J.
name: Marleau, G. -D.
name: Mollière, P.
name: Nasedkin, E.
name: Snellen, I. A. G.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Earth and Planetary Astrophysics (astro-ph.EP)
subject: FOS: Physical sciences

description: Aims. We aim to detect molecules in the atmosphere of the young forming companion PDS70 b by searching for atmospheric absorption features typical of substellar objects. Methods. We obtained medium-resolution (R$\approx$5075) spectra of the PDS70 planetary system with the SINFONI integral field spectrograph at the Very Large Telescope. We applied molecular mapping, based on cross-correlation with synthetic spectra, to identify signatures of molecular species in the atmosphere of the planet. Results. Although the planet emission is clearly detected when resampling the data to lower resolution, no molecular species could be identified with the cross-correlation technique. We estimated upper limits on the abundances of H$_2$O, CO and CH$_4$ ($\log(X_\mathrm{mol}) < -4.0$, $-4.1$ and $-4.9$, respectively) assuming a clear atmosphere, and we explored the impact of clouds, which increase the upper limits by a factor up to 0.7 dex. Assuming that the observations directly probe the planet's atmosphere, we found a lack of molecular species compared to other directly imaged companions or field objects. Under the assumption that the planet atmosphere presents similar characteristics to other directly imaged planets, we conclude that a dusty environment surrounds the planet, effectively obscuring any feature generated in its atmosphere. We quantify the extinction necessary to impede the detection ($A_V\approx16-17$ mag), pointing to the possibility of higher optical thickness than previously estimated from other studies. Finally, the non-detection of molecular species conflicts with atmospheric models previously proposed to describe the forming planet. Conclusions. To unveil how giant planets form, a comprehensive approach that includes constraints from multiple techniques needs to be undertaken. Molecular mapping emerges as an alternative to more classical techniques like SED fitting.
description: Accepted for publication in A&A (16 pages, 10 figures)
Electron pockets in the Fermi surface of hole-doped high-Tc superconductors
Creators: name: LeBoeuf, David
name: Doiron-Leyraud, Nicolas
name: Levallois, Julien
name: Daou, R.
name: Bonnemaison, J. -B.
name: Hussey, N. E.
name: Balicas, L.
name: Ramshaw, B. J.
name: Liang, Ruixing
name: Bonn, D. A.
name: Hardy, W. N.
name: Adachi, S.
name: Proust, Cyril
name: Taillefer, Louis
Publisher: name: arXiv
Year: 2008
Subjects: subject: Superconductivity (cond-mat.supr-con)
subject: FOS: Physical sciences

description: High-temperature superconductivity occurs as copper oxides are chemically tuned to have a carrier concentration intermediate between their metallic state at high doping and their insulating state at zero doping. The underlying evolution of the electron system in the absence of superconductivity is still unclear and a question of central importance is whether it involves any intermediate phase with broken symmetry. The Fermi surface of underdoped YBa2Cu3Oy and YBa2Cu4O8 was recently shown to include small pockets in contrast with the large cylinder characteristic of the overdoped regime1, pointing to a topological change in the Fermi surface. Here we report the observation of a negative Hall resistance in the magnetic field-induced normal state of YBa2Cu3Oy and YBa2Cu4O8, which reveals that these pockets are electron-like. We propose that electron pockets arise most likely from a reconstruction of the Fermi surface caused by the onset of a density-wave phase, as is thought to occur in the electron-doped materials near the onset of antiferromagnetic order Comparison with materials of the La2CuO4 family that exhibit spin/charge density-wave order suggests that a Fermi surface reconstruction also occurs in those materials, pointing to a generic property of high-Tc superconductors.
Correlative Spectral Analysis of Gamma-Ray Bursts using Swift-BAT and GLAST-GBM
Creators: name: Stamatikos, Michael
name: Sakamoto, Takanori
name: Band, David L.
Publisher: name: arXiv
Year: 2008
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: We discuss the preliminary results of spectral analysis simulations involving anticipated correlated multi-wavelength observations of gamma-ray bursts (GRBs) using Swift's Burst Alert Telescope (BAT) and the Gamma-Ray Large Area Space Telescope's (GLAST) Burst Monitor (GLAST-GBM), resulting in joint spectral fits, including characteristic photon energy (Epeak) values, for a conservative annual estimate of ~30 GRBs. The addition of BAT's spectral response will (i) complement in-orbit calibration efforts of GBM's detector response matrices, (ii) augment GLAST's low energy sensitivity by increasing the ~20-100 keV effective area, (iii) facilitate ground-based follow-up efforts of GLAST GRBs by increasing GBM's source localization precision, and (iv) help identify a subset of non-triggered GRBs discovered via off-line GBM data analysis. Such multi-wavelength correlative analyses, which have been demonstrated by successful joint-spectral fits of Swift-BAT GRBs with other higher energy detectors such as Konus-WIND and Suzaku-WAM, would enable the study of broad-band spectral and temporal evolution of prompt GRB emission over three energy decades, thus potentially increasing the science return without placing additional demands upon mission resources throughout their contemporaneous orbital tenure over the next decade.
description: 5 pages. Adapted from a contribution to the Proceedings of the 2008 Nanjing GRB Conference. Edited by Y. F. Huang, Z. G. Dai and B. Zhang
Augmenting a simulation campaign for hybrid computer model and field data experiments
Creators: name: Koermer, Scott
name: Loda, Justin
name: Noble, Aaron
name: Gramacy, Robert B.
Publisher: name: arXiv
Year: 2023
Subjects: subject: Methodology (stat.ME)
subject: FOS: Computer and information sciences

description: The Kennedy and O'Hagan (KOH) calibration framework uses coupled Gaussian processes (GPs) to meta-model an expensive simulator (first GP), tune its ``knobs" (calibration inputs) to best match observations from a real physical/field experiment and correct for any modeling bias (second GP) when predicting under new field conditions (design inputs). There are well-established methods for placement of design inputs for data-efficient planning of a simulation campaign in isolation, i.e., without field data: space-filling, or via criterion like minimum integrated mean-squared prediction error (IMSPE). Analogues within the coupled GP KOH framework are mostly absent from the literature. Here we derive a closed form IMSPE criterion for sequentially acquiring new simulator data for KOH. We illustrate how acquisitions space-fill in design space, but concentrate in calibration space. Closed form IMSPE precipitates a closed-form gradient for efficient numerical optimization. We demonstrate that our KOH-IMSPE strategy leads to a more efficient simulation campaign on benchmark problems, and conclude with a showcase on an application to equilibrium concentrations of rare earth elements for a liquid-liquid extraction reaction.
description: 39 Pages with supplementary material, 10 figures, submitted to Technometrics
Soziale Kontexte der digitalen Kommunikation und Probleme der Begrifflichkeiten: „New Literacy Studies“, „Multiliteracies“ und „Multimodality“ als Beispiele
Creators: name: Böck, Margit
name: Kress, Gunther
Publisher: name: Medienimpulse
Year: 2010

description: Dieser Beitrag thematisiert, inwieweit der aus der Schriftlichkeitsforschung stammende Begriff "Literacy" bzw. "Literacies" auf den Bereich der digitalen Kommunikation übertragen werden kann. Gegenwärtig wird so mit einem Begriff ein konzeptuelles Wirrwarr benannt: Die Literacy-Metapher verweist auf Ressourcen, Fähigkeiten, Technologien und ihre Potentiale, Funktionen, Kontexte usw. Zudem stellt sich die Frage, inwieweit disziplinäre und theoretische Hintergründe von traditionellen Literacy-Konzepten die aktuelle Auseinandersetzung mit neuen Phänomenen, die mit diesem Begriff bezeichnet werden, beeinflussen. Um dieses Durcheinander zu klären, differenzieren wir zwischen der sozialen, der technologischen und der semiotischen Ebene der Veränderung der Produktion von und des Umgangs mit Texten. Das Soziale steht dabei als generative Kraft im Vordergrund – eine Grundannahme, die auch die Ansätze der New Literacy Studies, der Multiliteracies und der Multimodality charakterisiert.
description: Medienimpulse, Bd. 48 Nr. 4 (2010): 4/2010 - Literacies
Internal kinematics of spiral galaxies in distant clusters III. Velocity fields from FORS2/MXU spectroscopy
Creators: name: Kutdemir, E.
name: Ziegler, B. L.
name: Peletier, R. F.
name: Da Rocha, C.
name: Kronberger, T.
name: Kapferer, W.
name: Schindler, S.
name: Böhm, A.
name: Jäger, K.
name: Kuntschner, Harald
name: Verdugo, M.
Publisher: name: arXiv
Year: 2008
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: (Abridged) We study the impact of cluster environment on the evolution of spiral galaxies by examining their structure and kinematics. Rather than two-dimensional rotation curves, we observe complete velocity fields by placing three adjacent and parallel FORS2 MXU slits on each object, yielding several emission and absorption lines. The gas velocity fields are reconstructed and decomposed into circular rotation and irregular motions using kinemetry. To quantify irregularities in the gas kinematics, we define three parameters: sigma_{PA} (standard deviation of the kinematic position angle), Delta phi (the average misalignment between kinematic and photometric position angles) and k_{3,5} (squared sum of the higher order Fourier terms). Using local, undistorted galaxies from SINGS, these can be used to establish the regularity of the gas velocity fields. Here we present the analysis of 22 distant galaxies in the MS0451.6-0305 field with 11 members at z=0.54. In this sample we find both field (4 out of 8) and cluster (3 out of 4) galaxies with velocity fields that are both irregular and asymmetric. We show that these fractions are underestimates of the actual number of galaxies with irregular velocity fields. The values of the (ir)regularity parameters for cluster galaxies are not very different from those of the field galaxies, implying that there are isolated field galaxies that are as distorted as the cluster members. None of the deviations in our small sample correlate with photometric/structural properties like luminosity or disk scale length in a significant way. Our 3D-spectroscopic method successfully maps the velocity field of distant galaxies, enabling the importance and efficiency of cluster specific interactions to be assessed quantitatively.
description: accepted for publication in A&A, high resolution version available at http://www.astro.rug.nl/~kutdemir/papers/
Variability in extragalactic class I methanol masers: New maser components toward NGC4945 and NGC253
Creators: name: McCarthy, Tiege
name: Ellingsen, Simon
name: Breen, Shari
name: Voronkov, Maxim
name: Chen, Xi
name: Qiao, Hai-Hua
Publisher: name: arXiv
Year: 2021
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: We have used the Australia Telescope Compact Array (ATCA) to make new observations of the 36.2-GHz ($4_{-1}\rightarrow3_0$E) methanol transition toward NGC 4945 and NGC 253. These observations have revealed the presence of new maser components toward these galaxies, and have provided the first clear evidence for variability in extragalactic class~I methanol masers. Alongside the new observations of NGC 4945 and NGC 253, we present the results of recent 36.2-GHz methanol maser searches toward 12 galaxies, placing upper limits on the emission from the 36.2-GHz class~I transition and the 37.7-GHz ($7_{2}\rightarrow8_1$E) class~II maser line toward these sources. Flux density values for the 7-mm continuum emission toward these sources are also reported where applicable. A re-analysis of the published 36.2-GHz methanol observations of Arp 220 undertaken as part of the search revealed some issues with previous imaging procedures. The re-analysis, combined with non-detections in independent follow-up observations suggest that there is no 36.2-GHz methanol emission toward Arp 220 stronger than 3.5 mJy in a 10 km s$^{-1}$ channel (5$σ$ upper limit).
description: Accepted into MNRAS 2019 November 1. 15 pages, 6 figures and 8 tables (7 in main text, 1 in appendix)
A quantitative Birkhoff Normal Form for the hinged-hinged beam equation with geometric nonlinearity
Creators: name: Di Gregorio, Laura
name: Lacarbonara, Walter
Publisher: name: arXiv
Year: 2023
Subjects: subject: Analysis of PDEs (math.AP)
subject: Dynamical Systems (math.DS)
subject: FOS: Mathematics
subject: 37K45, 74K10

description: We consider an undamped nonlinear hinged-hinged beam with stretching nonlinearity as an infinite dimensional hamiltonian system. We obtain analytically a quantitative Birkhoff Normal Form, via a nonlinear coordinate transformation that allows us to integrate the system up to a small reminder, providing a very precise description of small amplitude solutions over large time scales. The optimization of the involved estimates yields results obtained for realistic values of the physical quantities and of the perturbation parameter.
Non-perturbative phenomena in semiconductor four-wave mixing spectra
Creators: name: Erementchouk, Mikhail
name: Leuenberger, Michael N.
name: Sham, L. J.
Publisher: name: arXiv
Year: 2008
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: Non-perturbative phenomena in four-wave mixing spectra of semiconductors are studied using the exact solution of a widely used phenomenological non-linear equation of motion of the exciton polarization. It is shown that Coulomb interaction, included in the nonlinearity, leads to two characteristic effects, which are essentially of dynamical origin, -- a split of the exciton peak and a non-monotonous dependence of the response at the exciton frequency on the magnitude of the external field. Relations between the spectral features and the parameters of the system is obtained. It is found that the transition from perturbative to non-perturbative regimes is controlled by parameters inversely proportional to the decay rate. It implies that the condition of low excitation density does not necessarily warrant applicability of the perturbational approach.
description: 8 pages, 3 figures
The t-improper chromatic number of random graphs
Creators: name: Kang, Ross J.
name: McDiarmid, Colin
Publisher: name: arXiv
Year: 2008
Subjects: subject: Combinatorics (math.CO)
subject: Probability (math.PR)
subject: FOS: Mathematics
subject: 05C80, 05A16

description: We consider the $t$-improper chromatic number of the Erd{\H o}s-R{é}nyi random graph $G(n,p)$. The t-improper chromatic number $χ^t(G)$ of $G$ is the smallest number of colours needed in a colouring of the vertices in which each colour class induces a subgraph of maximum degree at most $t$. If $t = 0$, then this is the usual notion of proper colouring. When the edge probability $p$ is constant, we provide a detailed description of the asymptotic behaviour of $χ^t(G(n,p))$ over the range of choices for the growth of $t = t(n)$.
description: 12 pages
How Does a Dipolar Bose-Einstein Condensate Collapse?
Creators: name: Bohn, J. L.
name: Wilson, R. M.
name: Ronen, S.
Publisher: name: arXiv
Year: 2008
Subjects: subject: Atomic Physics (physics.atom-ph)
subject: FOS: Physical sciences

description: We emphasize that the macroscopic collapse of a dipolar Bose-Einstein condensate in a pancake-shaped trap occurs through local density fluctuations, rather than through a global collapse to the trap center. This hypothesis is supported by a recent experiment in a chromium condensate.
description: Proceedings of 17th International Laser Physics Workshop
The wolf masks of the Nootka Wolf ritual : a statement on transformation
Creators: name: Moogk, Susan Rosa Tovell
Publisher: name: University of British Columbia
Year: 2010

description: The thesis is an exploration and a critique of the reproduction problematic. The first section explores how three authors --Louis Althusser, Wally Seccombe, and Angela Miles, have constructed epistemologies of production and reproduction. Each author's location of reproduction of the relations of production and reproduction of labour power in base or superstructure, Family or State is explicated and discussed, and the relationship between Family and State suggested by each author is critically explored. In the second section of the paper I argue for a return to Marx's epistemology of production and reproduction-- that reproduction is always concrete production seen in continuous process. The question of what constitutes production in Marxist theory is raised and the works of Raymond Williams and E.P. Thompson are explored as alternate and more viable approaches to the problem. The position is advanced that the totality of social production and the totality of social relations must be included in analysis of Capitalist social formations. The final three sections explore some of the problems cf conceptualizing the Family, the State, and the relationship between them, with particular emphasis on their respective roles in reproducing labour power and the relations of production. Two major points of discussion are: 1) that the reproduction of labour power cannot be said to be the link between women's work, and consequently their oppression, in the home and in the State. That link must be found in historically specific processes and relations, rather than in the product (labour power) of the labour process; and 2) the reproduction of the relations of production cannot be assigned to any one 'sphere' of society, such as The Family, The State, or The Superstructure, nor can it be considered either wholey or mostly a matter of ideology. It must be seen as organized practice, which derives from attempts of ruling classes to incorporate and nullify challenges to their domination.
Well formedness vs weak well formedness
Creators: name: Przyjalkowski, Victor
Publisher: name: arXiv
Year: 2023
Subjects: subject: Algebraic Geometry (math.AG)
subject: FOS: Mathematics

description: In the literature there are two definitions of well formed varieties in weighted projective spaces. According to the first one, well formed variety is the one whose intersection with the singular locus of the ambient weighted projective space has codimension at least two, while, according to the second one, well formed variety is the one who does not contain in codimension one a singular stratum of the ambient weighted projective space. We show that these two definitions indeed differ, and show that they coincide for quasi-smooth weighted complete intersections of dimension at least 3.
description: 7 pages
Emergent Spacetime and The Origin of Gravity
Creators: name: Yang, Hyun Seok
Publisher: name: arXiv
Year: 2008
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: General Relativity and Quantum Cosmology (gr-qc)
subject: High Energy Physics - Phenomenology (hep-ph)
subject: Symplectic Geometry (math.SG)
subject: FOS: Physical sciences
subject: FOS: Mathematics

description: We present an exposition on the geometrization of the electromagnetic force. We show that, in noncommutative (NC) spacetime, there always exists a coordinate transformation to locally eliminate the electromagnetic force, which is precisely the Darboux theorem in symplectic geometry. As a consequence, the electromagnetism can be realized as a geometrical property of spacetime like gravity. We show that the geometrization of the electromagnetic force in NC spacetime is the origin of gravity, dubbed as the emergent gravity. We discuss how the emergent gravity reveals a novel, radically different picture about the origin of spacetime. In particular, the emergent gravity naturally explains the dynamical origin of flat spacetime, which is absent in Einstein gravity. This spacetime picture turns out to be crucial for a tenable solution of the cosmological constant problem.
description: v3; 80 pages, Cosmetic revision for publication and references added, to appear in JHEP
Certifiably Correct Range-Aided SLAM
Creators: name: Papalia, Alan
name: Fishberg, Andrew
name: O'Neill, Brendan W.
name: How, Jonathan P.
name: Rosen, David M.
name: Leonard, John J.
Publisher: name: arXiv
Year: 2023
Subjects: subject: Robotics (cs.RO)
subject: FOS: Computer and information sciences

description: We present the first algorithm to efficiently compute certifiably optimal solutions to range-aided simultaneous localization and mapping (RA-SLAM) problems. Robotic navigation systems increasingly incorporate point-to-point ranging sensors, leading to state estimation problems in the form of RA-SLAM. However, the RA-SLAM problem is significantly more difficult to solve than traditional pose-graph SLAM: ranging sensor models introduce non-convexity and single range measurements do not uniquely determine the transform between the involved sensors. As a result, RA-SLAM inference is sensitive to initial estimates yet lacks reliable initialization techniques. Our approach, certifiably correct RA-SLAM (CORA), leverages a novel quadratically constrained quadratic programming (QCQP) formulation of RA-SLAM to relax the RA-SLAM problem to a semidefinite program (SDP). CORA solves the SDP efficiently using the Riemannian Staircase methodology; the SDP solution provides both (i) a lower bound on the RA-SLAM problem's optimal value, and (ii) an approximate solution of the RA-SLAM problem, which can be subsequently refined using local optimization. CORA applies to problems with arbitrary pose-pose, pose-landmark, and ranging measurements and, due to using convex relaxation, is insensitive to initialization. We evaluate CORA on several real-world problems. In contrast to state-of-the-art approaches, CORA is able to obtain high-quality solutions on all problems despite being initialized with random values. Additionally, we study the tightness of the SDP relaxation with respect to important problem parameters: the number of (i) robots, (ii) landmarks, and (iii) range measurements. These experiments demonstrate that the SDP relaxation is often tight and reveal relationships between graph connectivity and the tightness of the SDP relaxation.
description: Accepted to Transactions on Robotics (T-RO)
PcDGAN: A Continuous Conditional Diverse Generative Adversarial Network For Inverse Design
Creators: name: Nobari, Amin Heyrani
name: Chen, Wei
name: Ahmed, Faez
Publisher: name: arXiv
Year: 2021
Subjects: subject: Machine Learning (cs.LG)
subject: FOS: Computer and information sciences

description: Engineering design tasks often require synthesizing new designs that meet desired performance requirements. The conventional design process, which requires iterative optimization and performance evaluation, is slow and dependent on initial designs. Past work has used conditional generative adversarial networks (cGANs) to enable direct design synthesis for given target performances. However, most existing cGANs are restricted to categorical conditions. Recent work on Continuous conditional GAN (CcGAN) tries to address this problem, but still faces two challenges: 1) it performs poorly on non-uniform performance distributions, and 2) the generated designs may not cover the entire design space. We propose a new model, named Performance Conditioned Diverse Generative Adversarial Network (PcDGAN), which introduces a singular vicinal loss combined with a Determinantal Point Processes (DPP) based loss function to enhance diversity. PcDGAN uses a new self-reinforcing score called the Lambert Log Exponential Transition Score (LLETS) for improved conditioning. Experiments on synthetic problems and a real-world airfoil design problem demonstrate that PcDGAN outperforms state-of-the-art GAN models and improves the conditioning likelihood by 69% in an airfoil generation task and up to 78% in synthetic conditional generation tasks and achieves greater design space coverage. The proposed method enables efficient design synthesis and design space exploration with applications ranging from CAD model generation to metamaterial selection.
Realistic Hybrid Inflation in 5D Orbifold SO(10) GUT
Creators: name: Fukuyama, Takeshi
name: Okada, Nobuchika
name: Osaka, Toshiyuki
Publisher: name: arXiv
Year: 2008
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: We discuss the smooth hybrid inflation scenario in the context of a simple supersymmetric SO(10) GUT in 5D orbifold. In this GUT model, the SO(10) gauge symmetry is broken down to the Pati-Salam (PS) gauge group, SU(4)$_c \times$ SU(2)$_L \times$ SU(2)$_R$, by orbifold boundary conditions and all matter and Higgs multiplets are placed only on the brane (PS brane) where only the PS symmetry is manifest. Further breaking of the Pati-Salam group to the Standard Model one is realized by VEVs of the Higgs multiplets $({\bf 4},{\bf 1},{\bf 2}) \oplus (\overline{\bf 4},{\bf 1},{\bf 2})$. The gauge coupling unification is successfully realized at $M_{\rm GUT} =4.6 \times 10^{17}$ GeV after incorporating the threshold corrections of the Kaluza-Klein modes, with the compactification scale (assumed to be the same as the PS symmetry breaking scale) $M_c = v_{\rm PS}= 1.2 \times 10^{16}$ GeV. We show that this orbifold GUT model can naturally leads us to the smooth hybrid inflation, which tunes out to be consistent with the WMAP 5-year data with the predicted $M_{\rm GUT}$ and $v_{PS}$ in the model.
description: 14 pages, 7 figures
A Kinematical Approach to Conformal Cosmology
Creators: name: Varieschi, Gabriele U.
Publisher: name: arXiv
Year: 2008
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: We present an alternative cosmology based on conformal gravity, as originally introduced by H. Weyl and recently revisited by P. Mannheim and D. Kazanas. Unlike past similar attempts our approach is a purely kinematical application of the conformal symmetry to the Universe, through a critical reanalysis of fundamental astrophysical observations, such as the cosmological redshift and others. As a result of this novel approach we obtain a closed-form expression for the cosmic scale factor R(t) and a revised interpretation of the space-time coordinates usually employed in cosmology. New fundamental cosmological parameters are introduced and evaluated. This emerging new cosmology does not seem to possess any of the controversial features of the current standard model, such as the presence of dark matter, dark energy or of a cosmological constant, the existence of the horizon problem or of an inflationary phase. Comparing our results with current conformal cosmologies in the literature, we note that our kinematic cosmology is equivalent to conformal gravity with a cosmological constant at late (or early) cosmological times. The cosmic scale factor and the evolution of the Universe are described in terms of several dimensionless quantities, among which a new cosmological variable delta emerges as a natural cosmic time. The mathematical connections between all these quantities are described in details and a relationship is established with the original kinematic cosmology by L. Infeld and A. Schild. The mathematical foundations of our kinematical conformal cosmology will need to be checked against current astrophysical experimental data, before this new model can become a viable alternative to the standard theory.
description: Improved version, with minor changes. 58 pages, including 7 figures and one table. Accepted for publication in General Relativity and Gravitation (GERG)
Steady State Convergence Acceleration of the Generalized Lattice Boltzmann Equation with Forcing Term through Preconditioning
Creators: name: Premnath, Kannan N.
name: Pattison, Martin J.
name: Banerjee, Sanjoy
Publisher: name: arXiv
Year: 2008
Subjects: subject: Computational Physics (physics.comp-ph)
subject: FOS: Physical sciences

description: Several applications exist in which lattice Boltzmann methods (LBM) are used to compute stationary states of fluid motions, particularly those driven or modulated by external forces. Standard LBM, being explicit time-marching in nature, requires a long time to attain steady state convergence, particularly at low Mach numbers due to the disparity in characteristic speeds of propagation of different quantities. In this paper, we present a preconditioned generalized lattice Boltzmann equation (GLBE) with forcing term to accelerate steady state convergence to flows driven by external forces. The use of multiple relaxation times in the GLBE allows enhancement of the numerical stability. Particular focus is given in preconditioning external forces, which can be spatially and temporally dependent. In particular, correct forms of moment-projections of source/forcing terms are derived such that they recover preconditioned Navier-Stokes equations with non-uniform external forces. As an illustration, we solve an extended system with a preconditioned lattice kinetic equation for magnetic induction field at low magnetic Prandtl numbers, which imposes Lorentz forces on the flow of conducting fluids. Computational studies, particularly in three-dimensions, for canonical problems show that the number of time steps needed to reach steady state is reduced by orders of magnitude with preconditioning. In addition, the preconditioning approach resulted in significantly improved stability characteristics when compared with the corresponding single relaxation time formulation.
description: 47 pages, 21 figures, for publication in Journal of Computational Physics
Art Academy
Creators: name: Rosenstingl, Herbert
Publisher: name: Medienimpulse
Year: 2010

description: Ein Spiel zum Zeichnen und Malen (lernen). Verlag: Nintendo Genre: Edu- und Infotainment Altersempfehlung: Kids (10-13 Jahre) / Jugendliche (14+ Jahre) Plattform: NDS
description: Medienimpulse, Bd. 48 Nr. 4 (2010): 4/2010 - Literacies
การไทเทรตกรด–เบสบนอุปกรณ์ตรวจวิเคราะห์ของไหลจุลภาคฐานกระดาษ (ไมโครแพด) โดยใช้อินดิเคเตอร์ธรรมชาติ
Creators: name: ภัทราวรรณ ศุภเลิศ
Publisher: name: หน่วยวิจัยวิทยาศาสตร์ เทคโนโลยี และสิ่งแวดล้อมเพื่อการเรียนรู้ คณะวิทยาศาสตร์ มหาวิทยาลัยศรีนครินทรวิโรฒ
Year: 2564
Subjects: การไทเทรตกรด-เบส
อินดิเคเตอร์ธรรมชาติ
อุปกรณ์ตรวจวิเคราะห์ของไหลจุลภาคฐานกระดาษ
ไมโครแพด
เคมีสีเขียว
ดอกฟ้าประทานพร

description: วารสารหน่วยวิจัยวิทยาศาสตร์ เทคโนโลยี และสิ่งแวดล้อมเพื่อการเรียนรู้ (JSTEL), 12, 2, 186-201
Vom Dämonischen. Zur politischen Medientheorie des Daniel Suarez
Creators: name: Barberi, Alessandro
Publisher: name: Medienimpulse
Year: 2017

description: Die Romane des Programmierers Daniel Suarez sind weit mehr als reine Fiktionen. Seine terminatorischen Inszenierungen des Endkampfs zwischen Maschinen und Menschen basieren auf äußerst realen Studien zu derzeitigen (Kriegs-)Technologien, die als politische Steuerungsmedien eingesetzt werden. Alessandro Barberi analysiert die Überlappung von sozialen und medialen Räumen bei einem Meister des Techno-Thrillers.
description: Medienimpulse, Bd. 50 Nr. 4 (2012): 4/2012 - Soziale und Mediale Räume
การพัฒนาทักษะการแก้ปัญหาของนักศึกษาครูเคมีด้วยกิจกรรมสะเต็มศึกษาแบบสืบเสาะหาความรู้บูรณาการกระบวนการออกแบบเชิงวิศวกรรม
Creators: name: กฤษณะ พวงระย้า
Publisher: name: หน่วยวิจัยวิทยาศาสตร์ เทคโนโลยี และสิ่งแวดล้อมเพื่อการเรียนรู้ คณะวิทยาศาสตร์ มหาวิทยาลัยศรีนครินทรวิโรฒ
Year: 2564
Subjects: ทักษะการแก้ปัญหา
กระบวนการออกแบบเชิงวิศวกรรม
กิจกรรมสะเต็มศึกษา

description: วารสารหน่วยวิจัยวิทยาศาสตร์ เทคโนโลยี และสิ่งแวดล้อมเพื่อการเรียนรู้ (JSTEL), 12, 2, 202-217
Toward a Universal Theory of Stable Evolution
Creators: name: Ván, Peter
Publisher: name: arXiv
Year: 2023
Subjects: subject: Physics and Society (physics.soc-ph)
subject: FOS: Physical sciences

description: The backbone of nonequilibrium thermodynamics is the stability structure, where entropy is related to a Lyapunov function of thermodynamic equilibrium. Stability is the background of natural selection: unstable systems are temporary, and stable ones survive. The physical concepts from the stability structure and the related formalism of constrained entropy inequality are universal by construction. Therefore, the mathematical tools and the physical concepts of thermodynamics help formulate dynamical theories of any systems in social and natural sciences.
description: 17 pages, 3 figures