cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
On the steady state collisional evolution of debris disks around M dwarfs
Creators: name: Morey, Etienne
name: Lestrade, Jean-Francois
Publisher: name: arXiv
Year: 2014
Subjects: subject: Earth and Planetary Astrophysics (astro-ph.EP)
subject: FOS: Physical sciences

description: Debris disks have been found primarily around intermediate and solar mass stars (spectral types A-K), but rarely around low-mass M-type stars. This scarcity of detections in M star surveys can be confronted with the predictions of the steady state collisional evolution model. First, we determine the parameters of the disk population evolved with this model and fit to the distribution of the fractional dust luminosities measured in the surveys of A- and FGK-type stars observed by the infrared satellite Spitzer. Thus, in our approach, we stipulate that the initial disk mass distribution is bimodal and that only high-mass collisionally-dominated disks are detected. The best determined parameter is the diameter $D_c$ of the largest planetesimals in the collisional cascade of the model, which ranges between 2 and 60 km, consistently for disks around A- and FGK-type stars. Second, we assume that the same disk population surrounds the M dwarfs that have been the subjects of debris disk searches in the far-infrared with Spitzer and at submillimeter wavelengths with radiotelescopes. We find, in the framework of our study, that this disk population, which has been fit to the AFGK data, is still consistent with the observed lack of disks around M dwarfs with Spitzer.
description: accepted for publication in Astronomy and Astrophysics on 21/feb/2014 ; 10 pages
Oriented right-angled Artin pro-$\ell$ groups and maximal pro-$\ell$ Galois groups
Creators: name: Blumer, Simone
name: Quadrelli, Claudio
name: Weigel, Thomas S.
Publisher: name: arXiv
Year: 2023
Subjects: subject: Number Theory (math.NT)
subject: FOS: Mathematics
subject: 12G05, 20E18, 20J06, 12F10

description: For a prime number $\ell$ we introduce and study oriented right-angled Artin pro-$\ell$ groups $G_{Γ,λ}$(oriented pro-$\ell$ RAAGs for short) associated to a finite oriented graph $Γ$ and a continuous group homomorphism $λ\colon\mathbb Z_\ell\to\mathbb Z_\ell^\times$. We show that an oriented pro-$\ell$ RAAG $G_{Γ,λ}$ is a Bloch-Kato pro-$\ell$ group if, and only if, $(G_{Γ,λ},θ_{Γ,λ})$ is an oriented pro-$\ell$ group of elementary type generalizing a recent result of I. Snopche and P. Zalesskii. Here $θ_{Γ,λ}\colon G_{Γ,λ}\to\mathbb Z_p^\times$ denotes the canonical $\ell$-orientation on $G_{Γ,λ}$. We invest some effort in order to show that oriented right-angled Artin pro-$\ell$ groups share many properties with right-angled Artin pro-$\ell$-groups or even discrete RAAG's, e.g., if $Γ$ is a specially oriented chordal graph, then $G_{Γ,λ}$ is coherent, generalizing a result of C. Droms. Moreover, in this case $(G_{Γ,λ},θ_{Γ,λ})$ has the Positselski-Bogomolov property generalizing a result of H. Servatius, C. Droms and B. Servatius for discrete RAAG's. If $Γ$ is a specially oriented chordal graph and ${\rm Im}(λ)\subseteq 1+4\mathbb Z_2$ in case that $\ell=2$, then ${\rm H}^\bullet(G_{Γ,λ},\mathbb F_\ell) \simeq Λ^\bullet(\ddotΓ^{\rm op})$ generalizing a well known result of M. Salvetti.
description: The differences between the 1st version (Apr'23) and the 2nd are: correction of a couple of minor misprints, dedication to the memory of Avinoam Mann
Affective Alteration: Co-Constructing Resilience in Alternative Psychotherapy Counselling Practice
Creators: name: Desjardins, Chloé
Publisher: name: Université d'Ottawa / University of Ottawa
Year: 2020
Subjects: Resilience
Psychotherapy
Posttraumatic
Subjectivities

description: The conceptual use of resilience has gained much popularity since the 1970s, positioning post-trauma resilience parallel to the paradigm of Posttraumatic Stress Disorder to offer a new possibility for healing and a new understanding of illness and suffering during the course of a neoliberal turn in psychiatry. In this thesis, it is shown how suffering and vulnerability becomes a source of authenticity rather than a source of a pathological illness. Through fieldwork with Resilience Summit, an alternative private counselling practice for psychotherapy that combines a feminist intersectional approach to traumatology, resilience is approached as a prototype capable of changing subjectivities because it permeates everyday feelings and actions. It does so by utilizing the flexible framework of resilience, as both inherent and cultivated, to create new capabilities, existential perspectives, and relationships in a therapeutic social network. There is the reconstruction of a condition of being through life narratives that are formed and reworked by the labour of emotional regulation and interaction. A new sense of resilient identity can consequently follow by achieving posttraumatic growth and collective engagement. However, Resilience Summit operates by means of affective governance which has been seen in contemporary resilience neoliberal discourses. It is possible to question to which degree Resilience Summit embraces neoliberal discourses of resilience in the context of a private practice.
A Method for Analyzing the Non-Stationary Nucleation and Overall Transition Kinetics. A Case of Water
Creators: name: Mokshin, Anatolii V.
name: Galimzyanov, Bulat N.
Publisher: name: arXiv
Year: 2013
Subjects: subject: Soft Condensed Matter (cond-mat.soft)
subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Materials Science (cond-mat.mtrl-sci)
subject: Computational Physics (physics.comp-ph)
subject: Data Analysis, Statistics and Probability (physics.data-an)
subject: FOS: Physical sciences

description: We present the statistical method as a direct extension of the mean first-passage time concept to the analysis of molecular dynamics simulation data of a phase transformation. According to the method, the mean first-passage time trajectories for the first $(i=1)$ as well as for the subsequent ($i=2$, $3$, $4$, $\ldots$) nucleation events should be extracted, that allows one to calculate the time-dependent nucleation rate, the critical value of the order parameter (the critical size), the waiting times for the nucleation events and the growth law of the nuclei -- i.e. all the terms, which are usually necessary to characterize the overall transition kinetics. There are no restrictions in the application of the method by the specific thermodynamic regions; and the nucleation rate parameters are extracted according to their basic definitions. The method differs from the Wedekind-Bartell scheme and its modification [A.V. Mokshin, B.N. Galimzyanov, J. Phys. Chem. B {\bf 116}, 11959 (2012)], where the passage-times for the first (largest) nucleus are evaluated only and where the average waiting time for the first nucleation event is accessible instead of the true steady-state nucleation time scale. We demonstrate an efficiency of the method by its application to the analysis of the vapor-to-liquid transition kinetics in water at the different temperatures. The nucleation rate/time characteristics and the droplet growth parameters are computed on the basis of the coarse-grained molecular dynamics simulation data.
description: 15 pages, 4 figures, and 1 table
Determination of subject-specific muscle fatigue rates under static fatiguing operations
Creators: name: Ma, Liang
name: Zhang, Wei
name: Hu, Bo
name: Chablat, Damien
name: Bennis, Fouad
name: Guillaume, François
Publisher: name: arXiv
Year: 2014
Subjects: subject: Robotics (cs.RO)
subject: FOS: Computer and information sciences

description: Cumulative local muscle fatigue may lead to potential musculoskeletal disorder (MSD) risks {\color{red}, and subject-specific muscle fatigability needs to be considered to reduce potential MSD risks.} This study was conducted to determine local muscle fatigue rate at shoulder joint level based on an exponential function derived from a muscle fatigue model. Forty male subjects participated in a fatiguing operation under a static posture with a range of relative force levels (14% - 33%). Remaining maximum muscle strengths were measured after different fatiguing sessions. The time course of strength decline was fitted to the exponential function. Subject-specific fatigue rates of shoulder joint moment strength were determined. Good correspondence ($R^2>0.8$) was found in the regression of the majority (35 out of 40 subjects). Substantial inter-individual variability in fatigue rate was found and discussed.
Development of usable applications featuring QR codes for enhancing interaction and acceptance: a case study
Creators: name: Hernando, Rubén
name: Macías, José A.
Publisher: name: Taylor & Francis
Year: 2022
Subjects: subject: Space Science
subject: Medicine
subject: Biotechnology
subject: 59999 Environmental Sciences not elsewhere classified
subject: FOS: Earth and related environmental sciences
subject: Ecology
subject: FOS: Biological sciences
subject: 69999 Biological Sciences not elsewhere classified
subject: 80699 Information Systems not elsewhere classified
subject: FOS: Computer and information sciences
subject: Science Policy
subject: Plant Biology

description: QR codes provide potential opportunities to improve interaction in different areas of application. Even so, this technology has been utilised in punctual and specific standalone applications, being barely applied to broader contexts, such as the educational one, where different scenarios can be considered to take advantage of the same QR-code approach. In this paper, key issues for the development of applications that utilise QR codes to improve sharing and availability of resources are presented, specifically focusing on improving interaction and acceptance. In this way, a holistic approach has been developed where the system is aimed at improving the interaction between educators and students. On the one hand, educators use a web interface to manage educational resources and announcements and automatically generate QR codes. On the other hand, students scan those QR codes using a mobile device, obtaining updated information related to their lectures. This scenario has been evaluated by educators and students, obtaining good results in terms of acceptance, cognitive burden, and overall usability. The approach provides development clues and the evaluation method that can be applied to different contexts, thus representing a generalisable solution.
Availability Model of a 5G-MEC System
Creators: name: Pathirana, Thilina
name: Nencioni, Gianfranco
Publisher: name: arXiv
Year: 2023
Subjects: subject: Networking and Internet Architecture (cs.NI)
subject: FOS: Computer and information sciences

description: Multi-access Edge Computing (MEC) is one of the enabling technologies of the fifth generation (5G) of mobile networks. MEC enables services with strict latency requirements by bringing computing capabilities close to the users. As with any new technology, the dependability of MEC is one of the aspects that need to be carefully studied. In this paper, we propose a two-level model to compute the availability of a 5G-MEC system. We then use the model to evaluate the availability of a 5G-MEC system under various configurations. The results show that having a single redundancy of the 5G-MEC elements leads an acceptable availability. To reach a high availability, the software failure intensity of the management elements of 5G and MEC should be reduced.
description: 10 pages, 11 figures, 3 tables. Accepted to be published at the 32nd International Conference on Computer Communications and Networks (ICCCN 2023)
Domus Sapientiae
Creators: name: Hauke, Petra
Publisher: name: Humboldt-Universität zu Berlin
Year: 2023
Subjects: subject: Kloster Sankt Mang Füssen
subject: Bibliothek
subject: Bibliotheksbau
subject: Barock
subject: Johann Jakob Herkomer
subject: 1652-1717
subject: Monastery Sankt Mang Füssen
subject: Library
subject: Library architecture
subject: Baroque architecture
subject: 000 Informatik, Informationswissenschaft, allgemeine Werke

description: Die Bibliothek des Klosters St. Mang im süddeutschen Füssen, nahe der österreichischen Grenze, ist Gegenstand der Dissertation. An ihrem Beispiel wird die Rolle des Zentralraums in der Bibliotheksarchitektur untersucht. Insbesondere wird folgenden Thesen nachgegangen: (1.) Die Bibliothek von St. Mang ist die erste nachweisbare realisierte Bibliotheksrotunde im europäischen Raum. (2.) Die Architektur der Bibliothek von St. Mang folgt neben den verbreiteten Architekturtheorien auch den Vorgaben von Bibliotheksnormen. (3.) Während andernorts dem ‚Mythos’ Bibliothek in additivem Raumschmuck Ausdruck verliehen wird, setzen die Programmentwerfer der Bibliothek von St. Mang dieselben Ideen in Architektur um: als wörtliche Umsetzung einer Domus sapientiae nach Prov. 9 sowie im Spiegel benedikt¬nischer Marienverehrung als Konzept einer Sedes sapientiae. Besonderes Augenmerk wird auf das Phänomen der Bibliotheksrotunde mit ihrem Tempelcharakter gelegt. Der Baukörper mit Refektorium und Bibliothek ragt in ungewöhnlicher Weise als überaus stark akzentuierendes Element aus dem klösterlichen Gesamtensemble hervor. Die sieben Fensterachsen der Bibliothek verstärken den Eindruck symbolhafter Architektur und werfen zudem die Frage auf, welche Vorbilder, Theorien, Quellen hier Pate gestanden haben könnten und inwieweit hier genuine Wissenschaftsarchitektur vorliegt.
description: The library of the monastery of St. Mang in southern Germany, near the Austrian border, is the subject of the dissertation. In her example, the role of the central space in library architecture is examined. In particular, the following theses are investigated: (1) The library of St. Mang is the first demonstrably realized library rotunda in Europe. (2.) In addition to the common architectural theories, the architecture of the library of St. Mang also follows the guidelines of library standards. (3.) While elsewhere the ‘myth’ of the library is expressed in additive room decoration, the programmers of the library of St. Mang translate the same ideas into architecture: as a literal implementation of a domus sapientiae according to Prov. 9 and in the mirror of Benedictine veneration of Mary as a concept of a Sedes sapientiae. Particular attention is paid to the phenomenon of the library rotunda with its temple character. The building with refectory and library stands out in an unusual way as an extremely strong accentuating element from the monastery's overall ensemble. The seven window axes of the library reinforce the impression of symbolic architecture and also raise the question of which models, theories, sources might have been the godfather here and to what extent genuine scientific architecture exists here.
Geometry of ecological coexistence and niche differentiation
Creators: name: Blumenthal, Emmy
name: Mehta, Pankaj
Publisher: name: arXiv
Year: 2023
Subjects: subject: Populations and Evolution (q-bio.PE)
subject: Statistical Mechanics (cond-mat.stat-mech)
subject: FOS: Biological sciences
subject: FOS: Physical sciences

description: A fundamental problem in ecology is to understand how competition shapes biodiversity and species coexistence. Historically, one important approach for addressing this question has been to analyze consumer resource models using geometric arguments. This has led to broadly applicable principles such as Tilman's $R^*$ and species coexistence cones. Here, we extend these arguments by constructing a novel geometric framework for understanding species coexistence based on convex polytopes in the space of consumer preferences. We show how the geometry of consumer preferences can be used to predict species which may coexist and enumerate ecologically-stable steady states and transitions between them. Collectively, these results provide a framework for understanding the role of species traits within niche theory.
description: 14 pages, 11 figures
Canonical Considerations in Pastoral Care of Persons in Marriages Between Roman Catholics and Buddhists in Thailand
Creators: name: Boonphao, Prajak
Publisher: name: Université Saint-Paul / Saint Paul University
Year: 2020
Subjects: Disparity of worship

description: Marriage is an institution based on natural law. Every person has the natural right to marriage which is, however, affected by cultural and social conditions. The pastors of the Church, therefore, have to make every effort to understand the particularity of situations within which marriage and family are lived today and respond accordingly through their pastoral action. Thailand is considered a Buddhist country due to the fact that the vast majority of its population is Buddhist. Most marriages celebrated in the Catholic Church are non-sacramental because a Buddhist is the spouse of the Catholic party. Canon 1086 of the 1983 Code states that due to the impediment of disparity of worship, a marriage between a person who was baptized in the Catholic Church or received into it and a non-baptized person is invalid. A dispensation from this impediment must be granted by the competent authority in order for the union to be valid. The conditions stated in cc. 1125–1126 must be taken into account for a dispensation to be granted. The thesis identifies the actual pastoral problems faced by persons in marriages with the disparity of worship and canonical questions faced by Church authorities; it also proposes canonical-pastoral responses to such cases. The first chapter explains in a systematic way the magisterial teaching of the Catholic Church on marriage in the modern world and the pertinent norms of the Code of Canon Law. Chapter Two is devoted to a brief study of the Buddhist teaching on marriage and of the Thai civil marriage laws. A comparison between the Catholic and the Buddhist understanding of marriage is presented in its conclusion. Chapter Three analyzes the principles governing marriage according to the 1983 Code of Canon Law, with comparison to the 1917 Code as needed. This chapter focuses especially on interreligious marriage. Chapter Four deals with the pastoral care of those Catholics who enter marriage with Buddhists in Thailand. Marriage preparation programs, the pre-marital investigation, the obligations of the Catholic party in a mixed marriage along with concrete pastoral solutions are given attention in this chapter.
Over By Christmas, St Pancras Station, November 2014
Creators: name: Newall, Helen
Publisher: name: Edge Hill University
Year: 2020
Subjects: subject: 190404 Drama, Theatre and Performance Studies
subject: FOS: Arts (arts, history of arts, performing arts, music)

description: Over By Christmas was a site responsive outdoor theatre piece designed to convey the narrative of the opening months of WWI to outdoor audiences in challenging environments (railway station platforms, or as at St Pancras, and Manchester Piccadilly, a concourse). It consisted of text and contemporary songs in a half hour work that made the railway setting a part of the work and thereby demonstrated the significance of the railways in WWI.
Capturing Aggregate Flexibility in Demand Response
Creators: name: Alizadeh, Mahnoosh
name: Scaglione, Anna
name: Goldsmith, Andrea
name: Kesidis, George
Publisher: name: arXiv
Year: 2014
Subjects: subject: Systems and Control (eess.SY)
subject: FOS: Electrical engineering, electronic engineering, information engineering

description: Flexibility in electric power consumption can be leveraged by Demand Response (DR) programs. The goal of this paper is to systematically capture the inherent aggregate flexibility of a population of appliances. We do so by clustering individual loads based on their characteristics and service constraints. We highlight the challenges associated with learning the customer response to economic incentives while applying demand side management to heterogeneous appliances. We also develop a framework to quantify customer privacy in direct load scheduling programs.
description: Submitted to IEEE CDC 2014
Attractive Solution of Binary Bose Mixtures: Liquid-Vapor Coexistence and Critical Point
Creators: name: Spada, Gabriele
name: Pilati, Sebastiano
name: Giorgini, Stefano
Publisher: name: arXiv
Year: 2023
Subjects: subject: Quantum Gases (cond-mat.quant-gas)
subject: Statistical Mechanics (cond-mat.stat-mech)
subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: We study the thermodynamic behavior of attractive binary Bose mixtures using exact path-integral Monte-Carlo methods. Our focus is on the regime of interspecies interactions where the ground state is in a self-bound liquid phase, stabilized by beyond mean-field effects. We calculate the isothermal curves in the pressure vs density plane for different values of the attraction strength and establish the extent of the coexistence region between liquid and vapor using the Maxwell construction. Notably, within the coexistence region, Bose-Einstein condensation occurs in a discontinuous way as the density jumps from the normal gas to the superfluid liquid phase. Furthermore, we determine the critical point where the line of first-order transition ends and investigate the behavior of the density discontinuity in its vicinity. We also point out that the density discontinuity at the transition could be observed in experiments of mixtures in traps.
description: v1: 6 pages, 5 figures. Supplemental material: 4 pages, 2 figures. Data available on zenodo.org; v2: minor improvements, matches PRL published version
On Data Augmentation for Models Involving Reciprocal Gamma Functions
Creators: name: Hamura, Yasuyuki
name: Irie, Kaoru
name: Sugasawa, Shonosuke
Publisher: name: Taylor & Francis
Year: 2022
Subjects: subject: Medicine
subject: Molecular Biology
subject: 69999 Biological Sciences not elsewhere classified
subject: FOS: Biological sciences
subject: 19999 Mathematical Sciences not elsewhere classified
subject: FOS: Mathematics

description: In this article, we introduce a new and efficient data augmentation approach to the posterior inference of the models with shape parameters when the reciprocal gamma function appears in full conditional densities. Our approach is to approximate full conditional densities of shape parameters by using Gauss’s multiplication formula and Stirling’s formula for the gamma function, where the approximation error can be made arbitrarily small. We use the techniques to construct efficient Gibbs and Metropolis–Hastings algorithms for a variety of models that involve the gamma distribution, Student’s t-distribution, the Dirichlet distribution, the negative binomial distribution, and the Wishart distribution. The proposed sampling method is numerically demonstrated through simulation studies. Supplementary materials for this article are available online.
Attitudes and preferences of digitally skilled dementia caregivers towards online psychoeducation: a cross-sectional study
Creators: name: Teles, Soraia
name: Ferreira, Ana
name: Paúl, Constança
Publisher: name: Taylor & Francis
Year: 2022
Subjects: subject: Medicine
subject: Neuroscience
subject: Biotechnology
subject: Sociology
subject: FOS: Sociology
subject: Cancer
subject: 111714 Mental Health
subject: FOS: Health sciences

description: Online interventions have been explored to support informal dementia caregivers. Despite favourable evidence on the effectiveness of such interventions, substantial non-use and dropout attrition are reported. This cross-sectional study characterises attitudes and preferences of digitally skilled dementia caregivers (N = 157) towards online psychoeducational interventions (OPIs) and explores associations of attitudes with sociodemographic, context of care, and internet use variables, as well as with previous use of psychosocial interventions, and valorisation of intervention features. Attitudes towards OPIs were moderately positive, but only one-third of caregivers trusted the effectiveness of OPIs. More participants would choose face-to-face (43%) than online interventions (31.4%). The former were seen as more trustworthy and less prone to dropout. Convenience was the most valued intervention feature, and preferences were stated for OPIs with friendly interfaces, free-of-jargon language and allowing to interact with professionals. The multivariable linear regression model suggests that using the internet at least once a week; having ever used a conventional psychosocial intervention; valuing an intervention for its convenience, sessions of short duration, self-personalisation of the plan, and progress self-monitoring, are associated with more favourable attitudes towards OPIs. Findings from this study should inform on the design, targeting and implementation of OPIs for dementia caregivers.
Parameter constraints from shadows of Kerr-Newman-dS black holes with cloud strings and quintessence
Creators: name: Cao, Wen-Fu
name: Liu, Wen-Fang
name: Wu, Xin
Publisher: name: arXiv
Year: 2023
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: The motion of photons around the Kerr-Newman-dS black hole surrounded by quintessence and a cloud of strings is investigated. The existence of the Carter constant leads to that of unstable circular photon orbits on a two-dimensional plane not limited to the equatorial plane and unstable spherical photon orbits in the three-dimensional space. These circular or spherical photon orbits can determine two impact parameters, which are used to calculate black hole shadows. For the case of a spherically symmetric nonrotating black hole, the black hole shadow is circular and its size is independent of an observation angle and a plane on which a circular photon orbit exists. The shadow sizes are significantly influenced by the parameters involving the cloud of strings, quintessence parameter, magnitude of quintessential state parameter, and cosmological constant. When the black hole is spinning and axially symmetric, the black hole shadow is dependent on the observation angle. The effects of the parameters excluding the spin parameter on the sizes of black hole shadows in the rotating case are similar to those in the nonrotating case. Based on the Event Horizon Telescope observations of M87*, the constraint of the curvature radius is used to constrain these parameters. For slowly rotating black holes, the allowed regions of the parameters including the cosmological constant are given.
description: 30 pages, 10 figures
Gate-dependent Pseudospin Mixing in Graphene/Boron Nitride Moire Superlattices
Creators: name: Shi, Zhiwen
name: Jin, Chenhao
name: Yang, Wei
name: Ju, Long
name: Horng, Jason
name: Lu, Xiaobo
name: Bechtel, Hans A.
name: Martin, Michael C.
name: Fu, Deyi
name: Wu, Junqiao
name: Watanabe, Kenji
name: Taniguchi, Takashi
name: Zhang, Yuanbo
name: Wang, Xuedong Bai Enge
name: Zhang, Guangyu
name: Wang, Feng
Publisher: name: arXiv
Year: 2014
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: Electrons in graphene are described by relativistic Dirac-Weyl spinors with a two-component pseudospin1-12. The unique pseudospin structure of Dirac electrons leads to emerging phenomena such as the massless Dirac cone2, anomalous quantum Hall effect2, 3, and Klein tunneling4, 5 in graphene. The capability to manipulate electron pseudospin is highly desirable for novel graphene electronics, and it requires precise control to differentiate the two graphene sub-lattices at atomic level. Graphene/boron nitride (graphene/BN) Moire superlattice, where a fast sub-lattice oscillation due to B-N atoms is superimposed on the slow Moire period, provides an attractive approach to engineer the electron pseudospin in graphene13-18. This unusual Moire superlattice leads to a spinor potential with unusual hybridization of electron pseudospins, which can be probed directly through infrared spectroscopy because optical transitions are very sensitive to excited state wavefunctions. Here, we perform micro-infrared spectroscopy on graphene/BN heterostructure and demonstrate that the Moire superlattice potential is dominated by a pseudospin-mixing component analogous to a spatially varying pseudomagnetic field. In addition, we show that the spinor potential depends sensitively on the gate-induced carrier concentration in graphene, indicating a strong renormalization of the spinor potential from electron-electron interactions. Our study offers deeper understanding of graphene pseudospin structure under spinor Moire potential, as well as exciting opportunities to control pseudospin in two-dimensional heterostructures for novel electronic and photonic nanodevices.
Free-form inverse design of arbitrary dispersive materials in nanophotonics
Creators: name: Gedeon, Johannes
name: Hassan, Emadeldeen
name: Lesina, Antonio Calà
Publisher: name: arXiv
Year: 2023
Subjects: subject: Optics (physics.optics)
subject: Computational Physics (physics.comp-ph)
subject: FOS: Physical sciences

description: In the last decades nanostructures have unlocked myriads of functionalities in nanophotonics by engineering light-matter interaction beyond what is possible with conventional bulk optics. The space of parameters available for design is practically unlimited due to the large variety of optical materials and geometries that can be realized by nanofabrication techniques. Thus, computational approaches are necessary to efficiently search for optimal solutions. In this paper, we enable the free-form inverse design in 3D of linear optical materials with arbitrary dispersion and anisotropy. This is achieved by implementing the adjoint method based on the complex-conjugate pole-residue pair model within a parallel finite-difference time-domain solver, suitable for high-performance computing systems. Our method is tested on the canonical nanophotonic problem of field enhancement in a gap region. The obtained free-form designs of metallic and dielectric materials satisfy the fundamental curiosity of how optimized nanostructures look like in 3D. Unconventional free-form designs revealed by our method, although may be challenging or unfeasible with current technology, bring new insight into how light interacts with nanostructures, and could provide new ideas to inspire forward design.
description: Main text: 13 pages, 8 figures Supplementary: 5 pages, 0 figures
GLAMER Part II: Multiple Plane Gravitational Lensing
Creators: name: Petkova, Margarita
name: Metcalf, R. Benton
name: Giocoli, Carlo
Publisher: name: arXiv
Year: 2013
Subjects: subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: FOS: Physical sciences

description: We present an extension to multiple planes of the gravitational lensing code {\small GLAMER}. The method entails projecting the mass in the observed light-cone onto a discrete number of lens planes and inverse ray-shooting from the image to the source plane. The mass on each plane can be represented as halos, simulation particles, a projected mass map extracted form a numerical simulation or any combination of these. The image finding is done in a source oriented fashion, where only regions of interest are iteratively refined on an initially coarse image plane grid. The calculations are performed in parallel on shared memory machines. The code is able to handle different types of analytic halos (NFW, NSIE, power-law, etc.), haloes extracted from numerical simulations and clusters constructed from semi-analytic models ({\small MOKA}). Likewise, there are several different options for modeling the source(s) which can be distributed throughout the light-cone. The distribution of matter in the light-cone can be either taken from a pre-existing N-body numerical simulations, from halo catalogs, or are generated from an analytic mass function. We present several tests of the code and demonstrate some of its applications such as generating mock images of galaxy and galaxy cluster lenses.
description: 14 pages, 10 figures, submitted to MNRAS
Resolving the Dirac Cone on the Surface of Bi2Te3 Topological Insulator Nanowires by Field-Effect Measurements
Creators: name: Gooth, Johannes
name: Hamdou, Bacel
name: Dorn, August
name: Zierold, Robert
name: Nielsch, Kornelius
Publisher: name: arXiv
Year: 2014
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: We validate the linear dispersion relation and resolve the Dirac cone on the surface of a single Bi2Te3 nanowire via a combination of field-effect and magnetoresistance measurements by which we unambiguously prove the topological insulator nature of the nanowire surface states. Moreover we show that the experimentally determined carrier concentration, mobility and cyclotron mass of the surface states are in excellent agreement with relativistic models. Our method provides a facile way to identify topological insulators that too small for angle-resolved photo emission spectroscopy.
Gravitational Energy, Local Holography and Non-equilibrium Thermodynamics
Creators: name: Freidel, Laurent
Publisher: name: arXiv
Year: 2013
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: We study the properties of gravitational system in finite regions bounded by gravitational screens. We present the detail construction of the total energy of such regions and of the energy and momentum balance equations due to the flow of matter and gravitational radiation through the screen. We establish that the gravitational screen possesses analogs of surface tension, internal energy and viscous stress tensor, while the conservations are analogs of non-equilibrium balance equations for a viscous system. This gives a precise correspondence between gravity in finite regions and non-equilibrium thermodynamics.
description: 41 pages, 3 figures
BCS-like disorder-driven instabilities and ultraviolet effects in nodal-line semimetals
Creators: name: Zhu, Siyu
name: Syzranov, Sergey
Publisher: name: arXiv
Year: 2023
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Disordered Systems and Neural Networks (cond-mat.dis-nn)
subject: Materials Science (cond-mat.mtrl-sci)
subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: Superconductivity (cond-mat.supr-con)
subject: FOS: Physical sciences

description: We study the effects of quenched disorder on electrons in a 3D nodal-line semimetal. Disorder leads to significant renormalisations of the quasiparticle properties due to ultraviolet processes, i.e., processes of scattering in a large band of momenta, of the width exceeding the inverse mean free path. As a result, observables such as the density of states and conductivity exhibit singular behaviour in a broad range of disorder strengths, excluding a small vicinity of the singular point. We find that, for example, the density of quasiparticle states diverges as a function of the disorder strength $g$ as $ρ(g,E)\propto |g_c(E)-g|^{-2}|E|$ for $g$ smaller than the critical value $g_c(E)$ and crosses over to a constant for $g$ very close to $g_c(E)$, where $E$ is the quasiparticle energy. For certain disorder symmetries, a 3D disordered nodal-line semimetal can be mapped to a 2D metal with attractive interactions. The described disorder-driven instabilities in such a nodal-line semimetal are mapped to Cooper and exciton-condensation instabilities in a 2D metal. For other disorder symmetries, the respective instabilities are similar but not exactly dual. We discuss experimental conditions favourable for the observation of the described effects.
description: 22 pages, 8 figures
Modelling a new, low CO2 emissions, hydrogen steelmaking process
Creators: name: Da Costa, Andrea Ranzani
name: Wagner, D.
name: Patisson, Fabrice
Publisher: name: arXiv
Year: 2014
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: In an effort to develop breakthrough technologies that enable drastic reduction in CO2 emissions from steel industry (ULCOS project), the reduction of iron ore by pure hydrogen in a direct reduction shaft furnace was investigated. After experimental and modelling studies, a 2D, axisymmetrical steady-state model called REDUCTOR was developed to simulate a counter-current moving bed reactor in which hematite pellets are reduced by pure hydrogen. This model is based on the numerical solution of the local mass, energy and momentum balances of the gas and solid species by the finite volume method. A single pellet sub-model was included in the global furnace model to simulate the successive reactions (hematite->magnetite ->wustite->iron) involved in the process, using the concept of additive reaction times. The different steps of mass transfer and possible iron sintering at the grain scale were accounted for. The kinetic parameters were derived from reduction experiments carried out in a thermobalance furnace, at different conditions, using small hematite cubes shaped from industrial pellets. Solid characterizations were also performed to further understand the microstrutural evolution. First results have shown that the use of hydrogen accelerates the reduction in comparison to CO reaction, making it possible to design a hydrogen-operated shaft reactor quite smaller than current MIDREX and HYL. Globally, the hydrogen steelmaking route based on this new process is technically and environmentally attractive. CO2 emissions would be reduced by more than 80%. Its future is linked to the emergence of the hydrogen economy.
Large eddy simulation of a low-pressure turbine cascade with turbulent end wall boundary layers
Creators: name: Morsbach, Christian
name: Bergmann, Michael
name: Tosun, Adem
name: Klose, Bjoern F.
name: Kügeler, Edmund
name: Franke, Matthias
Publisher: name: arXiv
Year: 2023
Subjects: subject: Fluid Dynamics (physics.flu-dyn)
subject: FOS: Physical sciences

description: We present results of implicit large eddy simulation (LES) and different Reynolds-averaged Navier-Stokes (RANS) models of the MTU 161 low pressure turbine at an exit Reynolds number of 90,000 and exit Mach number of 0.6. The LES results are based on a high order discontinuous Galerkin method and the RANS is computed using a classical finite-volume approach. The paper discusses the steps taken to create realistic inflow boundary conditions in terms of end wall boundary layer thickness and free stream turbulence intensity. This is achieved by tailoring the input distribution of total pressure and temperature, Reynolds stresses and turbulent length scale to a Fourier series based synthetic turbulence generator. With this procedure, excellent agreement with the experiment can be achieved in terms of blade loading at midspan and wake total pressure losses at midspan and over the channel height. Based on the validated setup, we focus on the discussion of secondary flow structures emerging due to the interaction of the incoming boundary layer and the turbine blade and compare the LES to two commonly used RANS models. Since we are able to create consistent setups for both LES and RANS, all discrepancies can be directly attributed to physical modelling problems. We show that both a linear eddy viscosity model and a differential Reynolds stress model coupled with a state-of-the-art correlation-based transition model fail, in this case, to predict the separation induced transition process around midspan. Moreover, their prediction of secondary flow losses leaves room for improvement as shown by a detailed discussion turbulence kinetic energy and anisotropy fields.
description: invited submission to Flow, Turbulence and Combustion Special Issue: 13th ERCOFTAC Workshop on Direct and Large Eddy Simulation - DLES13
On the Duality of Erasures and Defects
Creators: name: Kim, Yongjune
name: Kumar, B V K Vijaya
Publisher: name: arXiv
Year: 2014
Subjects: subject: Information Theory (cs.IT)
subject: FOS: Computer and information sciences

description: In this paper, the duality of erasures and defects will be investigated by comparing the binary erasure channel (BEC) and the binary defect channel (BDC). The duality holds for channel capacities, capacity achieving schemes, minimum distances, and upper bounds on the probability of failure to retrieve the original message. Also, the binary defect and erasure channel (BDEC) will be introduced by combining the properties of the BEC and the BDC. It will be shown that the capacity of the BDEC can be achieved by the coding scheme that combines the encoding for the defects and the decoding for the erasures. This coding scheme for the BDEC has two separate redundancy parts for correcting erasures and masking defects. Thus, we will investigate the problem of redundancy allocation between these two parts.
description: 40 pages, 8 figures, submitted to IEEE Transactions on Information Theory
Optimal Bounds for Integrals with Respect to Copulas and Applications
Creators: name: Hofer, Markus
name: Iacò, Maria Rita
Publisher: name: arXiv
Year: 2014
Subjects: subject: Optimization and Control (math.OC)
subject: FOS: Mathematics

description: We consider the integration of two-dimensional, piecewise constant functions with respect to copulas. By drawing a connection to linear assignment problems, we can give optimal upper and lower bounds for such integrals and construct the copulas for which these bounds are attained. Furthermore, we show how our approach can be extended in order to approximate extremal values in very general situations. Finally, we apply our approximation technique to problems in financial mathematics and uniform distribution theory, such as the model-independent pricing of first-to-default swaps.
Predicting Failure: Acoustic Emission of Berlinite under Compression
Creators: name: Nataf, Guillaume F
name: Castillo-Villa, Pedro O
name: Sellappan, Pathikumar
name: Kriven, Waltraud M
name: Vives, Eduard
name: Planes, Antoni
name: Salje, Ekhard K H
Publisher: name: arXiv
Year: 2014
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: Acoustic emission has been measured and statistical characteristics have been analyzed during the stress-induced collapse of porous berlinite, AlPO4, containing up to 50 vol% porosity. Stress collapse occurs in a series of individual events (avalanches), and each avalanche leads to a jerk in sample compression with corresponding acoustic emission (AE) signals. The distribution of AE avalanche energies can be approximately described by a power law over a large stress interval. We observed several collapse mechanisms whereby less porous minerals show the superposition of independent jerks, which were not related to the major collapse at the failure stress. In highly porous berlinite (40% and 50%) an increase of the energy emission occurred near the failure point. In contrast, the less porous samples did not show such an increase in energy emission. Instead, in the near vicinity of the main failure point they showed a reduction in the energy exponent to ~ 1.4, which is consistent with the value reported for compressed porous systems displaying critical behavior. This indicated that a critical avalanche regime with a lack of precursor events occurs. In this case, all preceding large events were false alarms and unrelated to the main failure event. Our results identify a method to use pico-seismicity detection of foreshocks to warn of mine collapse before the main failure collapse occurs, which can be applied for highly porous materials only.
description: accepted for publication in Journal of Physics: Condensed Matter
Operating the GridPix detector with helium-isobutane gas mixtures for a high-precision, low-mass Time Projection Chamber
Creators: name: Cavoto, G.
name: Dutsov, C.
name: Gruber, M.
name: Hildebrandt, M.
name: Hume, T. D.
name: Kaminski, J.
name: Neuhaus, F.
name: Papa, A.
name: Renga, F.
name: Schmidt-Wellenburg, P.
name: Schott, M.
name: Vitali, B.
name: Voena, C.
Publisher: name: arXiv
Year: 2023
Subjects: subject: Instrumentation and Detectors (physics.ins-det)
subject: High Energy Physics - Experiment (hep-ex)
subject: FOS: Physical sciences

description: High precision experiments with muons and pions often require tracking charged particles with $O(100~μ\mathrm{m})$ single-hit resolution, possibly with particle identification capabilities, down to very low momenta ($p \lesssim 100$~MeV/$c$). In such conditions, the particle trajectories are strongly affected by the interaction with the detector material, and the reconstruction of the kinematic observables consequently deteriorates. A good compromise between resolution and material budget can be obtained with a Time Projection Chamber (TPC), if very light gases and a high-granularity readout are used. In this paper, we present a characterization of the GridPix detector in helium-isobutane gas mixtures, within a TPC with 9~cm maximum drift. Measurements of the main electron drift properties for these gas mixtures are also presented.
description: 13 pages, 13 figures, submitted to JINST
Primitive axial algebras of Jordan type
Creators: name: Hall, J I
name: Rehren, F
name: Shpectorov, S
Publisher: name: arXiv
Year: 2014
Subjects: subject: Rings and Algebras (math.RA)
subject: Group Theory (math.GR)
subject: FOS: Mathematics

description: An axial algebra over the field $\mathbb F$ is a commutative algebra generated by idempotents whose adjoint action has multiplicity-free minimal polynomial. For semisimple associative algebras this leads to sums of copies of $\mathbb F$. Here we consider the first nonassociative case, where adjoint minimal polynomials divide $(x-1)x(x-η)$ for fixed $0\neqη\neq 1$. Jordan algebras arise when $η=\frac{1}{2}$, but our motivating examples are certain Griess algebras of vertex operator algebras and the related Majorana algebras. We study a class of algebras, including these, for which axial automorphisms like those defined by Miyamoto exist, and there classify the $2$-generated examples. For $η\neq \frac{1}{2}$ this implies that the Miyamoto involutions are $3$-transpositions, leading to a classification.
description: 41 pages; comments welcome
On multichannel film dosimetry with channel-independent perturbations
Creators: name: Méndez, Ignasi
name: Peterlin, Primož
name: Hudej, Rihard
name: Strojnik, Andrej
name: Casar, Božidar
Publisher: name: arXiv
Year: 2014
Subjects: subject: Medical Physics (physics.med-ph)
subject: FOS: Physical sciences

description: Purpose: Different multichannel methods for film dosimetry have been proposed in the literature. Two of them are the weighted mean method and the method put forth by Micke et al and Mayer et al. The purpose of this work was to compare their results and to develop a generalized channel-independent perturbations framework in which both methods enter as special cases. Methods: Four models of channel-independent perturbations were compared: weighted mean, Micke-Mayer method, uniform distribution and truncated normal distribution. A closed-form formula to calculate film doses and the associated Type B uncertainty for all four models was deduced. To evaluate the models, film dose distributions were compared with planned and measured dose distributions. At the same time, several elements of the dosimetry process were compared: film type EBT2 versus EBT3, different waiting-time windows, reflection mode versus transmission mode scanning, and planned versus measured dose distribution for film calibration and for gamma-index analysis. The methods and the models described in this study are publicly accessible through IRISEU. Alpha 1.1 (http://www.iriseu.com). IRISEU. is a cloud computing web application for calibration and dosimetry of radiochromic films. Results: The truncated normal distribution model provided the best agreement between film and reference doses, both for calibration and gamma-index verification, and proved itself superior to both the weighted mean model, which neglects correlations between the channels, and the Micke-Mayer model, whose accuracy depends on the properties of the sensitometric curves. Conclusions: The truncated normal distribution model of channel-independent perturbations was found superior to the other three models under comparison and we propose its use for multichannel dosimetry.
description: 11 pages, 2 figures