cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
galstreams: A Library of Milky Way Stellar Stream Footprints and Tracks
Creators: name: Mateu, Cecilia
Publisher: name: arXiv
Year: 2022
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: Nearly a hundred stellar streams have been found to date around the Milky Way and the number keeps growing at an ever faster pace. Here we present the galstreams library, a compendium of angular position, distance, proper motion and radial velocity track data for nearly a hundred (95) Galactic stellar streams. The information published in the literature has been collated and homogenised in a consistent format and used to provide a set of features uniformly computed throughout the library: e.g. stream length, end points, mean pole, stream's coordinate frame, polygon footprint, and pole and angular momentum tracks. We also use the information compiled to analyse the distribution of several observables across the library and to assess where the main deficiencies are found in the characterisation of individual stellar streams, as a resource for future follow-up efforts. The library is intended to facilitate keeping track of new discoveries and to encourage the use of automated methods to characterise and study the ensemble of known stellar streams by serving as a starting point. The library is publicly available as a Python package and served at the galstreams GitHub repository.
description: Accepted for publication at MNRAS. 29 pages, 19 figures, 2 tables, updated to match final version (new figures added! conclusions unchanged). The library of stellar stream tracks is publicly available at https://github.com/cmateu/galstreams
The Presence and Effects of Foreign Multinational Firms on the Survival of Domestic Agricultural Products Export Firms in Tanzania
Creators: name: Shilinde, John S.M.
name: Aikaeli, Jehovaness
name: Shilinde, John S.M.
name: Aikaeli, Jehovaness
Publisher: name: Unknown
Year: 2022
Subjects: subject: International Relations/Trade
subject: foreign multinational firms
subject: domestically owned firms
subject: discrete-time survival model
subject: Tanzania

description: This paper investigates whether and how the presence of export-oriented foreign multinational firms affects the survival of domestically owned Agri-export firms in Tanzania using the 2010 – 2020 transaction firm-level customs data. The empirical analysis is based on the life table estimator function and the logistic regression survival model with fixed effects. After controlling for firm specific characteristics such as age, size, export volume, productivity, number of destinations per firm, and number of products per firm, we find that foreign firms have higher survival rates than domestic firms and at some point, they positively influence the survival of the domestic firms in international agricultural exports. The positive impact on the domestic firms could be due to knowledge spillovers from the foreign firms. The results also suggest that the presence of foreign-owned firms has a significant impact on the exit hazard of domestic firms. This perseverance could be due to the reasons that mostly foreign firms export to countries where they originate, sometimes they are aware to market information than local firms. Finally, the findings offer insightful implications including supporting locally owned firms with increased international markets access to information and continue improving business and investment environment for foreign multinational in agricultural exports.
Magnetic nanowire based high resolution magnetic force microscope probes
Creators: name: Littlehei, P. T.
name: Liu, J.
name: Woodson, M.
name: Tang, J.
name: Park, C.
name: Zhang, Q.
name: Yang, G.
name: Kato, S.
name: Kim, J. W.
name: Qin, L. C.
name: Zhou, O.
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2005

description: We report an efficient process for controlled fabrication of high-resolution magnetic force microscope probes using preformed magnetic nanowires. Nickel and cobalt nanowires produced by electrodeposition were directly assembled onto the tip of a commercial atomic force microscope cantilever with controlled orientation and length by dielectrophoresis. The properties of these nanowire-based probes are characterized.
Higher order anisotropies in hydrodynamics
Creators: name: Csanad, M.
name: Szabo, A.
name: Lokos, S.
name: Bagoly, A.
Publisher: name: arXiv
Year: 2015
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: Nuclear Theory (nucl-th)
subject: FOS: Physical sciences

description: In the last years it has been revealed that if measuring relative to higher order event planes $Ψ_n$, higher order flow coefficients $v_n$ for $n>2$ can be measured. It also turned out that Bose-Einstein (HBT) correlation radii also show 3rd order oscillations if measured versus the third order event plane $Ψ_3$. In this paper we investigate how these observables can be described via analytic hydro solutions and hydro parameterizations. We also investigate the time evolution of asymmetry coefficients and the mixing of velocity field asymmetries and density asymmetries.
description: 8 pages, 6 figures. Presented at the X Workshop on Particle Correlations and Femtoscopy (WPCF 2014), Gyongyos, Hungary
BEAU GESTE leer epub P.C. WREN
Creators: name: Strachan
Publisher: name: Zenodo
Year: 2024

description: BEAU GESTE de P.C. WREN

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BEAU GESTE

P.C. WREN

Número de páginas: 672

Idioma: CASTELLANO

Formatos: Pdf, ePub, MOBI, FB2

ISBN: 9788477025627

Editorial: VALDEMAR

Año de edición: 2007

 

 

 

 

 

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Overview

Percival Christopher Wren nació en Devonshire, Inglaterra, en 1885. Tras cursar sus estudios en Oxford, se alistó en la Legión Extranjera francesa en busca de aventuras. A su vuelta a Inglaterra, Wren se casó y se instaló en una casa de campo donde llevaría una vida de caballero rural. En 1924 publica la obra que le daría fama universal: Beau Geste, un clásico de las novelas de aventuras traducido a numerosas lenguas y adaptado al cine en varias ocasiones (la más conocida de ellas es la que dirigió en 1939 William Wellman, protagonizada por Gary Cooper). A esta novela seguirían otras muchas, una cada año, entre las que destacan Wages of Virtue (1916), Beau Sabreur (1926) y Beau Ideal (1928), cuyas peripecias se desarrollan en la India, África e Inglaterra.Beau Geste comienza con el relato de un oficial de la Legión Extranjera sobre un extraño suceso que vivió en el pasado. Acosado por las guerrillas nativas, un fuerte de avanzada de la Legión situado en Zinderneuf, Nigeria, solicitó refuerzos urgentemente. Cuando las tropas se acercaron al fuerte observaron a numerosos legionarios apostados en sus almenas. Pero no se movían ni respondían a sus llamadas: más tarde comprobarán que estaban todos muertos. La segunda parte de la novela narra, a modo de flashback, cómo la misteriosa desaparición del zafiro Agua Azul, propiedad de la señora Patricia Brandon, lleva a sus tres sobrinos, Michael, Digby y John Geste, a alistarse en la Legión Extranjera. Los tres hermanos serán destinados a un fuerte perdido al norte de Nigeria donde «le cafard», la locura del desierto debida a la inactividad expectante, acaba haciendo mella en todo el destacamento.
(3106) Trafford Nadin
Creators: name: Professions, Victorian
Publisher: name: University of Oxford
Year: 2022
Subjects: subject: 220201 Business and Labour History
subject: FOS: Philosophy, ethics and religion
subject: History
subject: 140203 Economic History
subject: FOS: Economics and business

description: This three-year research project began in January 2014 and investigated whether, during the Victorian period, the professions formed a distinct self-sustaining social group with its own mores and values. The project looked at 16,000 individuals drawn from census data for Alnwick, Brighton, Bristol, Dundee, Greenock, Leeds, Merthyr Tydfil, Morpeth, and Winchester. The research project was funded by the UK Economic & Social Research Council and was based at the Universities of Oxford and Northumbria.
Predicting highway lane-changing maneuvers: A benchmark analysis of machine and ensemble learning algorithms
Creators: name: Khelfa, Basma
name: Ba, Ibrahima
name: Tordeux, Antoine
Publisher: name: arXiv
Year: 2022
Subjects: subject: Machine Learning (cs.LG)
subject: Signal Processing (eess.SP)
subject: Physics and Society (physics.soc-ph)
subject: FOS: Computer and information sciences
subject: FOS: Electrical engineering, electronic engineering, information engineering
subject: FOS: Physical sciences

description: Understanding and predicting highway lane-change maneuvers is essential for driving modeling and its automation. The development of data-based lane-changing decision-making algorithms is nowadays in full expansion. We compare empirically in this article different machine and ensemble learning classification techniques to the MOBIL rule-based model using trajectory data of European two-lane highways. The analysis relies on instantaneous measurements of up to twenty-four spatial-temporal variables with the four neighboring vehicles on current and adjacent lanes. Preliminary descriptive investigations by principal component and logistic analyses allow identifying main variables intending a driver to change lanes. We predict two types of discretionary lane-change maneuvers: overtaking (from the slow to the fast lane) and fold-down (from the fast to the slow lane). The prediction accuracy is quantified using total, lane-changing and lane-keeping errors and associated receiver operating characteristic curves. The benchmark analysis includes logistic model, linear discriminant, decision tree, naïve Bayes classifier, support vector machine, neural network machine learning algorithms, and up to ten bagging and stacking ensemble learning meta-heuristics. If the rule-based model provides limited predicting accuracy, the data-based algorithms, devoid of modeling bias, allow significant prediction improvements. Cross validations show that selected neural networks and stacking algorithms allow predicting from a single observation both fold-down and overtaking maneuvers up to four seconds in advance with high accuracy.
description: 25 pages, 11 figures
Structural influence on atomic hopping and electronic states of Pd-based bulk metallic glasses
Creators: name: Löffler, Jörg F.
name: Johnson, William L.
name: Tang, X. P.
name: Wu, Yue
name: Schwarz, R. B.
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2005

description: Atomic motion and electronic structures of Pd–Ni–Cu–P bulk metallic glasses were investigated using 31P nuclear magnetic resonance. The hopping rate of P atoms was determined by the stimulated echo technique. Significant hopping was observed in all alloys well below the glass transition temperature. Increasing the Cu content to above 25 at. % increases P hopping significantly, consistent with the previous finding that the openness of the structure increases with Cu content. In contrast, P hopping is not influenced by changes of local electronic states at P sites, induced by the substitution of Ni by Cu.
N49: the first robust discovery of a recombining plasma in an extra galactic supernova remnant
Creators: name: Uchida, Hiroyuki
name: Koyama, Katsuji
name: Yamaguchi, Hiroya
Publisher: name: arXiv
Year: 2015
Subjects: subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: FOS: Physical sciences

description: Recent discoveries of recombining plasmas (RPs) in supernova remnants (SNRs) have dramatically changed our understanding of SNR evolution. To date, a dozen of RP SNRs have been identified in the Galaxy. Here we present Suzaku deep observations of four SNRs in the Large Magellanic Cloud (LMC), N49, N49B, N23, and DEM L71, for accurate determination of their plasma state. Our uniform analysis reveals that only N49 is in the recombining state among them, which is the first robust discovery of a RP from an extra-galactic SNR. Given that RPs have been identified only in core-collapse SNRs, our result strongly suggests a massive star origin of this SNR. On the other hand, no clear evidence for a RP is confirmed in N23, from which detection of recombination lines and continua was previously claimed. Comparing the physical properties of the RP SNRs identified so far, we find that all of them are categorized into the "mixed-morphology" class and interacting with surrounding molecular clouds. This might be a key to solve formation mechanisms of the RPs.
description: 8 pages, 4 figures, Accepted for publication in ApJ
Three-dimensional Newtonian gravity with cosmological constant and torsion
Creators: name: Concha, Patrick
name: Rodríguez, Evelyn
name: Rubio, Gustavo
name: Yañez, Paola
Publisher: name: arXiv
Year: 2022
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: In this paper we present an alternative cosmological extension of the three-dimensional extended Newtonian Chern-Simons gravity by switching on the torsion. The theory is obtained as a non-relativistic limit of an enhancement and $U(1)$-enlargement of the so-called teleparallel algebra and can be seen as the teleparallel analogue of the Newtonian gravity theory. The infinite-dimensional extension of our result is also explored through the Lie algebra expansion method. An infinite-dimensional torsional Galilean gravity model is presented which in the vanishing cosmological constant limit reproduces the infinite-dimensional extension of the Galilean gravity theory.
description: 19 pages
Call and Response: A Time-Resolved Study of Chromospheric Evaporation in a Large Solar Flare
Creators: name: Sellers, Sean G.
name: Milligan, Ryan O.
name: McAteer, R. T. James
Publisher: name: arXiv
Year: 2022
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: We studied an X1.6 solar flare produced by NOAA AR 12602 on 2014 October 22. The entirety of this event was covered by RHESSI, IRIS, and Hinode/EIS, allowing analysis of the chromospheric response to a nonthermal electron driver. We derived the energy contained in nonthermal electrons via RHESSI spectral fitting, and linked the time-dependent parameters of this call to the response in Doppler velocity, density, and nonthermal width across a broad temperature range. The total energy injected was $4.8\times10^{30}$ erg, and lasted $352$ seconds. This energy drove explosive chromospheric evaporation, with a delineation in both Doppler and nonthermal velocities at the flow reversal temperature, between 1.35--1.82 MK. The time of peak electron injection (14:06 UT) corresponded to the time of highest velocities. At this time, we found 200 km s$^{-1}$ blueshifts in the core of Fe XXIV, which is typically assumed to be at rest. Shortly before this time, the nonthermal electron population had the shallowest spectral index ($\approx$ 6), corresponding to the peak nonthermal velocity in Si IV and Fe XXI. Nonthermal velocities in Fe XIV, formed near the flow reversal temperature were low, and not correlated with density or Doppler velocity. Nonthermal velocities in ions with similar temperatures were observed to increase and correlate with Doppler velocities, implying unresolved flows surrounding the flow reversal point. This study provides a comprehensive, time-resolved set of chromospheric diagnostics for a large X-class flare, along with a time-resolved energy injection profile, ideal for further modeling studies.
description: 23 pages, 14 figures, 2 tables, Accepted for publication in ApJ
[PDF] The Learning Game: Teaching Kids to Think for Themselves, Embrace Challenge, and Love Learning by Ana Lorena Fábrega
Creators: name: Jones
Publisher: name: Zenodo
Year: 2024

description: The Learning Game: Teaching Kids to Think for Themselves, Embrace Challenge, and Love Learning by Ana Lorena Fábrega

 

 

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The Learning Game: Teaching Kids to Think for Themselves, Embrace Challenge, and Love Learning

Ana Lorena Fábrega

Page: 304

Format: pdf, ePub, mobi, fb2

ISBN: 9781804090091

Publisher: Harriman House

 

Free full audio books downloads The Learning Game: Teaching Kids to Think for Themselves, Embrace Challenge, and Love Learning MOBI PDB by Ana Lorena Fábrega 9781804090091 (English Edition)

Overview

How did we conclude that the best way to prepare kids for the future is to cluster them into classrooms by age and grade, forcing them to learn the same things, at the same time and pace, seven hours a day, five days a week, for twelve years? We trust the school system to prepare our kids for the future. We get excited when they get good grades, or disappointed if they don’t. But we rarely stop to question whether school is teaching our children the right things in the right way. Kids could get good at playing the game of school, but are they really learning? Teacher-turned-edupreneur Ana Lorena Fábrega, known by her students as Ms. Fab, invites us to rethink education. In THE LEARNING GAME, she reveals how traditional schooling has gone wrong, and proposes a series of actionable strategies to help kids learn. - What if we guide kids to think for themselves? - Should we encourage kids to take risks and tackle projects of their own? - How do we help kids learn to love learning? Answering these questions and many more, THE LEARNING GAME will arm you with practical tools to design a new approach to learning—one that leaves behind the game of school and prepares your kids for the game of life.
Supplementary Information from How tight are beetle hugs? Attachment in mating leaf beetles.
Creators: name: Voigt, Dagmar
name: Tsipenyuk, Alexey
name: Varenberg, Michael
Publisher: name: The Royal Society
Year: 2017
Subjects: subject: 110601 Biomechanics
subject: FOS: Health sciences
subject: 60801 Animal Behaviour
subject: FOS: Biological sciences

description: Additional tables, figures, and movie legends
Demonstration of Floquet engineering using pulse driving in a diamond two-level system under a large-amplitude modulation
Creators: name: Nishimura, Shunsuke
name: Itoh, Kohei M.
name: Ishi-Hayase, Junko
name: Sasaki, Kento
name: Kobayashi, Kensuke
Publisher: name: arXiv
Year: 2022
Subjects: subject: Quantum Physics (quant-ph)
subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: The nitrogen-vacancy (NV) center in a diamond is a promising platform for Floquet system. We investigate NV center's Floquet state driven by Carr-Purcell sequence in a large-amplitude AC magnetic field using the sequential readout. We observe the dynamics represented as Bessel functions up to 211th orders high in a systematic and quantitative agreement with the theoretical model. Furthermore, numerical calculations show that the effect of finite pulse duration and error limits the modulation amplitude available for Floquet engineering. This work provides an approach to precisely investigate Floquet engineering, showing the extendable range of modulation amplitude, for two-level systems.
description: 12pages, 7 figures
Fabrication and characterization of single carbon nanotube emitters as point electron sources
Creators: name: Zhao, Gongpu
name: Qin, Lu Chang
name: Zhang, Han
name: Zhou, Otto
name: Tang, Jie
name: Zhang, Qi
name: Zhang, Jian
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2006

description: Individual carbon nanotube electron field emitters with good controllability have been fabricated in a two-step process involving (a) producing micron-size carbon fibers which contain single carbon nanotubes at their cores by a chemical vapor deposition method and (b) exposing the nanotubes by fracturing the fiber with mechanical forces and mounting the fiber to a copper wire. These fiber-nanotube electron emitters show low operating voltage, generate high field enhancement, and produce fine electron beams. The field emission characteristics and durability of this structure offer promising applications for analytical instruments where high performance point electron sources are required.
(3107) Joseph Nadin
Creators: name: Professions, Victorian
Publisher: name: University of Oxford
Year: 2022
Subjects: subject: 220201 Business and Labour History
subject: FOS: Philosophy, ethics and religion
subject: History
subject: 140203 Economic History
subject: FOS: Economics and business

description: This three-year research project began in January 2014 and investigated whether, during the Victorian period, the professions formed a distinct self-sustaining social group with its own mores and values. The project looked at 16,000 individuals drawn from census data for Alnwick, Brighton, Bristol, Dundee, Greenock, Leeds, Merthyr Tydfil, Morpeth, and Winchester. The research project was funded by the UK Economic & Social Research Council and was based at the Universities of Oxford and Northumbria.
Experimental quantum key distribution without monitoring signal disturbance
Creators: name: Takesue, Hiroki
name: Sasaki, Toshihiko
name: Tamaki, Kiyoshi
name: Koashi, Masato
Publisher: name: arXiv
Year: 2015
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: Since the invention of Bennett-Brassard 1984 (BB84) protocol, many quantum key distribution (QKD) protocols have been proposed and some protocols are operated even in field environments. One of the striking features of QKD is that QKD protocols are provably secure unlike cryptography based on computational complexity assumptions. It has been believed that, to guarantee the security of QKD, Alice and Bob have to monitor the statistics of the measurement outcomes which are used to determine the amount of the privacy amplification to generate a key. Recently a new type of QKD protocol, called round robin differential phase shift (RRDPS) protocol, was proposed, and remarkably this protocol can generate a key without monitoring any statistics of the measurement outcomes. Here we report an experimental realization of the RRDPS protocol. We used a setup in which Bob randomly chooses one from four interferometers with different pulse delays so that he could implement phase difference measurements for all possible combinations with five-pulse time-bin states. Using the setup, we successfully distributed keys over 30 km of fiber, making this the first QKD experiment that does not rely on signal disturbance monitoring.
description: 8 pages, 4 figures
Large Interferometer For Exoplanets (LIFE): VII. Practical implementation of a five-telescope kernel-nulling beam combiner with a discussion on instrumental uncertainties and redundancy benefits
Creators: name: Hansen, Jonah T.
name: Ireland, Michael J.
name: Laugier, Romain
name: collaboration, the LIFE
Publisher: name: arXiv
Year: 2022
Subjects: subject: Instrumentation and Methods for Astrophysics (astro-ph.IM)
subject: Earth and Planetary Astrophysics (astro-ph.EP)
subject: FOS: Physical sciences

description: (Abridged) Context: In the previous paper in this series, we identified that a pentagonal arrangement of five telescopes, using a kernel-nulling beam combiner, shows notable advantages for some important performance metrics for a space-based mid-infrared nulling interferometer over several other considered configurations for the detection of Earth-like exoplanets around solar-type stars. Aims: We aim to produce a physical implementation of a kernel-nulling beam combiner for such a configuration, as well as a discussion of systematic and stochastic errors associated with the instrument. Methods: We developed a mathematical framework around a nulling beam combiner, and then used it along with a space interferometry simulator to identify the effects of systematic uncertainties. Results: We find that errors in the beam combiner optics, systematic phase errors and the RMS fringe tracking errors result in instrument limited performance at $\sim$4-7 $μ$m, and zodiacal limited at $\gtrsim$10 $μ$m. Assuming a beam splitter reflectance error of $|ΔR| = 5\%$ and phase shift error of $Δϕ= 3$ degrees, we find that the fringe tracking RMS should be kept to less than 3 nm in order to be photon limited, and the systematic piston error be less than 0.5 nm to be appropriately sensitive to planets with a contrast of 1$\times 10^{-7}$ over a 4-19 $μ$m bandpass. We also identify that the beam combiner design, with the inclusion of a well positioned shutter, provides an ability to produce robust kernel observables even if one or two collecting telescopes were to fail. The resulting four telescope combiner, when put into an X-array formation, results in a transmission map with a relative signal-to-noise ratio equivalent to 80% of the fully functioning X-array combiner.
description: 14 Pages, 15 Figures, 3 Tables. Accepted for publication in A&A. Other papers in the LIFE series are also available. First paper: arXiv:2101.07500, preceding paper: arXiv:2201.04891. Latest update fixed some minor errors
Supplementary Information from How tight are beetle hugs? Attachment in mating leaf beetles
Creators: name: Voigt, Dagmar
name: Tsipenyuk, Alexey
name: Varenberg, Michael
Publisher: name: The Royal Society
Year: 2017
Subjects: subject: 110601 Biomechanics
subject: FOS: Health sciences
subject: 60801 Animal Behaviour
subject: FOS: Biological sciences

description: Additional tables, figures, and movie legends
Dependence on the thermodynamic state of self-diffusion of pseudo hard-spheres
Creators: name: Marchioni, L.
name: Di Muro, M. A.
name: Hoyuelos, M.
Publisher: name: arXiv
Year: 2022
Subjects: subject: Statistical Mechanics (cond-mat.stat-mech)
subject: Soft Condensed Matter (cond-mat.soft)
subject: FOS: Physical sciences

description: Self-diffusion, $D$, in a system of particles that interact with a pseudo hard sphere potential is analyzed. Coupling with a solvent is represented by a Langevin thermostat, characterized by the damping time $t_d$. The hypotheses that $D=D_0 φ$ is proposed, where $D_0$ is the small concentration diffusivity and $φ$ is a thermodynamic function that represents the effects of interactions as concentration is increased. Molecular dynamics simulations show that different values of the noise intensity modify $D_0$ but do not modify $φ$. This result is consistent with the assumption that $φ$ is a thermodynamic function, since the thermodynamic state is not modified by the presence of damping and noise.
Dynamics of swarmalators: A pedagogical review
Creators: name: Sar, Gourab Kumar
name: Ghosh, Dibakar
Publisher: name: arXiv
Year: 2022
Subjects: subject: Adaptation and Self-Organizing Systems (nlin.AO)
subject: Chaotic Dynamics (nlin.CD)
subject: Applied Physics (physics.app-ph)
subject: FOS: Physical sciences

description: Swarmalators have emerged as a new paradigm for dynamical collective behavior of multi-agent systems due to the interplay of synchronization and swarming that they inherently incorporate. Their dynamics have been explored with different coupling topologies, interaction functions, external forcing, noise, competitive interactions, and from other important viewpoints. Here we take a systematic approach and review the collective dynamics of swarmalators analytically and/or numerically. Long-term states of position aggregation and phase synchronization are revealed in this perspective with some future problems.
description: 7 pages, 4 figures, comments welcome
Field emission of electrons from a Cs-doped single carbon nanotube of known chiral indices
Creators: name: Qin, Lu Chang
name: Zhao, Gongpu
name: Tang, Jie
name: Zhang, Qi
name: Yang, Guang
name: Zhou, Otto
name: Zhang, Han
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2006

description: The authors report the effects of Cs doping on the field emission properties of a five-shell single carbon nanotube. The chiral indices of each shell of this carbon nanotube have been determined using nanobeam electron diffraction, which has four semiconducting shells and one metallic shell in the middle. From the Fowler-Nordheim plots, a reduction from 4.8 to 3.8 eV has been observed in the work function of the single carbon nanotube before and after Cs doping.
Evocube: a Genetic Labeling Framework for Polycube-Maps
Creators: name: Dumery, Corentin
name: Protais, François
name: Mestrallet, Sébastien
name: Bourcier, Christophe
name: Ledoux, Franck
Publisher: name: arXiv
Year: 2022
Subjects: subject: Graphics (cs.GR)
subject: FOS: Computer and information sciences

description: Polycube-maps are used as base-complexes in various fields of computational geometry, including the generation of regular all-hexahedral meshes free of internal singularities. However, the strict alignment constraints behind polycube-based methods make their computation challenging for CAD models used in numerical simulation via Finite Element Method (FEM). We propose a novel approach based on an evolutionary algorithm to robustly compute polycube-maps in this context. We address the labeling problem, which aims to precompute polycube alignment by assigning one of the base axes to each boundary face on the input. Previous research has described ways to initialize and improve a labeling via greedy local fixes. However, such algorithms lack robustness and often converge to inaccurate solutions for complex geometries. Our proposed framework alleviates this issue by embedding labeling operations in an evolutionary heuristic, defining fitness, crossover, and mutations in the context of labeling optimization. We evaluate our method on a thousand smooth and CAD meshes, showing Evocube converges to valid labelings on a wide range of shapes. The limitations of our method are also discussed thoroughly.
Interconnecting a System Having a Single Input-to-State Gain With a System Having a Region-Dependent Input-to-State Gain
Creators: name: Shiromoto, Humberto Stein
name: Andrieu, Vincent
name: Prieur, Christophe
Publisher: name: arXiv
Year: 2015
Subjects: subject: Optimization and Control (math.OC)
subject: Systems and Control (eess.SY)
subject: FOS: Mathematics
subject: FOS: Electrical engineering, electronic engineering, information engineering

description: For an ISS system, by analyzing local and non-local properties, it is obtained different input-to-state gains. The interconnection of a system having two input-to-state gains with a system having a single ISS gain is analyzed. By employing the Small Gain Theorem for the local (resp. non-local) gains composition, it is concluded about the local (resp. global) stability of the origin (resp. of a compact set). Additionally, if the region of local stability of the origin strictly includes the region attraction of the compact set, then it is shown that the origin is globally asymptotically stable. An example illustrates the approach.
Entanglement Signature of Hinge Arcs, Fermi Arcs, and Crystalline Symmetry Protection in Higher-Order Weyl Semimetals
Creators: name: Zhou, Yao
name: Ye, Peng
Publisher: name: arXiv
Year: 2022
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Materials Science (cond-mat.mtrl-sci)
subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: The existence of $1/2$ modes in the entanglement spectrum (ES) has been shown to be a powerful quantum-informative signature of boundary states of gapped topological phases of matter, e.g., topological insulators and topological superconductors, where the finite bulk gap allows us to establish a crystal-clear correspondence between $1/2$ modes and boundary states. Here we investigate the recently proposed higher-order Weyl semimetals (HOWSM), where bulk supports gapless higher-order Weyl nodes and boundary supports hinge arcs and Fermi arcs. We find that the aim of unambiguously identifying higher-order boundary states ultimately drives us to make full use of eigen quantities of the entanglement Hamiltonian: ES as well as Schmidt vectors (entanglement wavefunctions, abbr. EWF). We demonstrate that, while both hinge arcs and Fermi arcs contribute to $1/2$ modes, the EWFs corresponding to hinge arcs and Fermi arcs are respectively localized on the virtual hinges and surfaces of the partition. Besides, by means of various symmetry-breaking partitions, we can identify the minimal crystalline symmetries that protect boundary states. Therefore, for gapless topological phases such as HOWSMs, we can combine ES and EWF to universally identify boundary states and potential symmetry requirement. While HOWSMs are prototypical examples of gapless phases, our work sheds light on general theory of entanglement signature in gapless topological phases of matter.
description: 8pages
Impact of magnetic fields on Population III star formation
Creators: name: Saad, Cynthia R.
name: Bromm, Volker
name: Eid, Mounib El
Publisher: name: arXiv
Year: 2022
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: FOS: Physical sciences

description: The theory of the formation of the first stars in the Universe, the so-called Population III (Pop III), has until now largely neglected the impact of magnetic fields. Complementing a series of recent studies of the magneto-hydrodynamic (MHD) aspects of Pop III star formation, we here carry out a suite of idealized numerical experiments where we ascertain how the fragmentation properties of primordial protostellar discs are modified if MHD effects are present. Specifically, starting from cosmological initial conditions, we focus on the central region in a select minihalo at redshift $z\sim$ 25, inserting a magnetic field at an intermediate evolutionary stage, normalized to a fraction of the equipartition value. To explore parameter space, we consider different field geometries, including uniform, radial, toroidal, and poloidal field configurations, with the toroidal configuration being the most realistic. The collapse of the gas is followed for $\sim$8 orders of magnitude in density after the field was inserted, until a maximum of $10^{15}{\rm \,cm}^{-3}$ is reached. We find that the magnetic field leads to a delay in the collapse of the gas. Moreover, the toroidal field has the strongest effect on the collapse as it inhibits the fragmentation of the emerging disc surrounding the central core and leads to the formation of a more massive core. The full understanding of the formation of Pop~III stars and their mass distribution thus needs to take into account the effect of magnetic fields. We further conclude that ideal MHD is only a first step in this endeavor, to be followed-up with a comprehensive treatment of dissipative effects, such as ambipolar diffusion and Ohmic dissipation.
description: Accepted by MNRAS
(3100) Henry Barton Brown
Creators: name: Professions, Victorian
Publisher: name: University of Oxford
Year: 2022
Subjects: subject: 220201 Business and Labour History
subject: FOS: Philosophy, ethics and religion
subject: History
subject: 140203 Economic History
subject: FOS: Economics and business

description: This three-year research project began in January 2014 and investigated whether, during the Victorian period, the professions formed a distinct self-sustaining social group with its own mores and values. The project looked at 16,000 individuals drawn from census data for Alnwick, Brighton, Bristol, Dundee, Greenock, Leeds, Merthyr Tydfil, Morpeth, and Winchester. The research project was funded by the UK Economic & Social Research Council and was based at the Universities of Oxford and Northumbria.
Functionalization of carbon nanotubes with proteins and quantum dots in aqueous buffer solutions
Creators: name: Prakash, R.
name: Superfine, Rich
name: Falvo, Michael R.
name: Washburn, S.
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2006

description: We report here on a method of suspending carbon nanotubes (CNTs) in aqueous buffer solutions and functionalizing CNTs with a molecule that is ``sticky'' to proteins. The specific bifunctional molecule used in this study is 1-pyrene butanoic acid succidymidyl ester (1-pbase). We report successful protein and quantum dot functionalization of the CNTs, using 1-pbase as a linking agent.
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Publisher: name: Zenodo
Year: 2024

description: Coudre vite et bien pan Line, Jaque

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Overview
Atomic force microscopy measurement of the Young’s modulus and hardness of single LaB6 nanowires
Creators: name: An, Bai
name: Qin, Lu Chang
name: Tang, Jie
name: Zhang, Lin
name: Zhang, Han
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2008

description: We have employed the atomic force microscopy based (a) three-point bending and (b) nanoindentation methods to obtain the Young’s modulus and hardness of single La B 6 nanowires. The Young’s modulus, E = 467.1 ± 15.8 GPa , is the same as that of the La B 6 single crystals but larger than the sinteredpolycrystalline La B 6 samples. The nanoindentationhardness of the La B 6 nanowire is H = 70.6 ± 2.1 GPa at an indent depth of 4.6 nm , which is higher than that of the La B 6 single crystals, La B 6 polycrystals, and W metals. A superior resistance against thermal vibration, field modification, and ion bombardment is expected for the La B 6 nanowires as a field-emission point electron source.
Classical-physics applications for Finsler $b$ space
Creators: name: Foster, Joshua
name: Lehnert, Ralf
Publisher: name: arXiv
Year: 2015
Subjects: subject: Classical Physics (physics.class-ph)
subject: FOS: Physical sciences

description: The classical propagation of certain Lorentz-violating fermions is known to be governed by geodesics of a four-dimensional pseudo-Finsler $b$ space parametrized by a prescribed background covector field. This work identifies systems in classical physics that are governed by the three-dimensional version of Finsler $b$ space and constructs a geodesic for a sample non-constant choice for the background covector. The existence of these classical analogues demonstrates that Finsler $b$ spaces possess applications in conventional physics, which may yield insight into the propagation of SME fermions on curved manifolds.
description: 8 pages, 2 figures, accepted for publication in Physics Letters B
Explainable Artificial Intelligence Applications in Cyber Security: State-of-the-Art in Research
Creators: name: Zhang, Zhibo
name: Hamadi, Hussam Al
name: Damiani, Ernesto
name: Yeun, Chan Yeob
name: Taher, Fatma
Publisher: name: arXiv
Year: 2022
Subjects: subject: Cryptography and Security (cs.CR)
subject: FOS: Computer and information sciences

description: This survey presents a comprehensive review of current literature on Explainable Artificial Intelligence (XAI) methods for cyber security applications. Due to the rapid development of Internet-connected systems and Artificial Intelligence in recent years, Artificial Intelligence including Machine Learning (ML) and Deep Learning (DL) has been widely utilized in the fields of cyber security including intrusion detection, malware detection, and spam filtering. However, although Artificial Intelligence-based approaches for the detection and defense of cyber attacks and threats are more advanced and efficient compared to the conventional signature-based and rule-based cyber security strategies, most ML-based techniques and DL-based techniques are deployed in the black-box manner, meaning that security experts and customers are unable to explain how such procedures reach particular conclusions. The deficiencies of transparency and interpretability of existing Artificial Intelligence techniques would decrease human users' confidence in the models utilized for the defense against cyber attacks, especially in current situations where cyber attacks become increasingly diverse and complicated. Therefore, it is essential to apply XAI in the establishment of cyber security models to create more explainable models while maintaining high accuracy and allowing human users to comprehend, trust, and manage the next generation of cyber defense mechanisms. Although there are papers reviewing Artificial Intelligence applications in cyber security areas and the vast literature on applying XAI in many fields including healthcare, financial services, and criminal justice, the surprising fact is that there are currently no survey research articles that concentrate on XAI applications in cyber security.
description: Accepted by IEEE Access
A remark on the Tournament game
Creators: name: Clemens, Dennis
name: Mikalački, Mirjana
Publisher: name: arXiv
Year: 2015
Subjects: subject: Combinatorics (math.CO)
subject: FOS: Mathematics

description: We study the Maker-Breaker tournament game played on the edge set of a given graph $G$. Two players, Maker and Breaker claim unclaimed edges of $G$ in turns, and Maker wins if by the end of the game she claims all the edges of a pre-defined goal tournament. Given a tournament $T_k$ on $k$ vertices, we determine the threshold bias for the $(1:b)$ $T_k$-tournament game on $K_n$. We also look at the $(1:1)$ $T_k$-tournament game played on the edge set of a random graph ${\mathcal{G}_{n,p}}$ and determine the threshold probability for Maker's win. We compare these games with the clique game and discuss whether a random graph intuition is satisfied.
Spin flip probability of electron in a uniform magnetic field
Creators: name: Hammond, Richard T.
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2012

description: The probability that an electromagnetic wave can flip the spin of an electron is calculated. It is assumed that the electron resides in a uniform magnetic field and interacts with an incoming electromagnetic pulse. The scattering matrix is constructed and the time needed to flip the spin is calculated.
Effective Field Theory Islands from Perturbative and Nonperturbative Four-Graviton Amplitudes
Creators: name: Bern, Zvi
name: Herrmann, Enrico
name: Kosmopoulos, Dimitrios
name: Roiban, Radu
Publisher: name: arXiv
Year: 2022
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: Theoretical data obtained from physically sensible field and string theory models suggest that gravitational Effective Field Theories (EFTs) live on islands that are tiny compared to current general bounds determined from unitarity, causality, crossing symmetry, and a good high-energy behavior. In this work, we present explicit perturbative and nonperturbative $2 \to 2$ graviton scattering amplitudes and their associated low-energy expansion in spacetime dimensions $D\geq 4$ to support this notion. Our new results include a first nonperturbative example consisting of a $D=4$, $\mathcal{N}=1$ supersymmetric field theory that is coupled weakly to gravity. We show that this nonperturbative model lies on the same islands identified using four-dimensional perturbative models based on string theory and minimally-coupled matter circulating a loop. Furthermore, we generalize the previous four-dimensional perturbative models based on string theory and minimally-coupled massive spin-0 and spin-1 states circulating in the loop to $D$ dimensions. Remarkably, we again find that the low-energy EFT coefficients lie on small islands. These results offer a useful guide towards constraining possible extensions of Einstein gravity.
description: 26 pages, 6 figures, 11 ancillary files
A Finslerian version of 't Hooft Deterministic Quantum Models
Creators: name: Torromé, Ricardo Gallego
Publisher: name: arXiv
Year: 2005
Subjects: subject: Mathematical Physics (math-ph)
subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: Using the Finsler structure living in the phase space associated to the tangent bundle of the configuration manifold, deterministic models at the Planck scale are obtained. The Hamiltonian function are constructed directly from the geometric data and some assumptions concerning time inversion symmetry. The existence of a maximal acceleration and speed is proved for Finslerian deterministic models. We investigate the spontaneous symmetry breaking of the orthogonal symmetry SO(6N) of the Hamiltonian of a deterministic system. This symmetry break implies the non-validity of the argument used to obtain Bell's inequalities for spin states. It is introduced and motivated in the context of Randers spaces an example of simple 't Hooft model with interactions.
description: 25 pages; no figures. String discussion deleted. Some minor changes
(3101) Winifred Gertrude Brown
Creators: name: Professions, Victorian
Publisher: name: University of Oxford
Year: 2022
Subjects: subject: 220201 Business and Labour History
subject: FOS: Philosophy, ethics and religion
subject: History
subject: 140203 Economic History
subject: FOS: Economics and business

description: This three-year research project began in January 2014 and investigated whether, during the Victorian period, the professions formed a distinct self-sustaining social group with its own mores and values. The project looked at 16,000 individuals drawn from census data for Alnwick, Brighton, Bristol, Dundee, Greenock, Leeds, Merthyr Tydfil, Morpeth, and Winchester. The research project was funded by the UK Economic & Social Research Council and was based at the Universities of Oxford and Northumbria.
ASTROMER: A transformer-based embedding for the representation of light curves
Creators: name: Donoso-Oliva, C.
name: Becker, I.
name: Protopapas, P.
name: Cabrera-Vives, G.
name: M., Vishnu
name: Vardhan, Harsh
Publisher: name: arXiv
Year: 2022
Subjects: subject: Instrumentation and Methods for Astrophysics (astro-ph.IM)
subject: Machine Learning (cs.LG)
subject: FOS: Physical sciences
subject: FOS: Computer and information sciences

description: Taking inspiration from natural language embeddings, we present ASTROMER, a transformer-based model to create representations of light curves. ASTROMER was pre-trained in a self-supervised manner, requiring no human-labeled data. We used millions of R-band light sequences to adjust the ASTROMER weights. The learned representation can be easily adapted to other surveys by re-training ASTROMER on new sources. The power of ASTROMER consists of using the representation to extract light curve embeddings that can enhance the training of other models, such as classifiers or regressors. As an example, we used ASTROMER embeddings to train two neural-based classifiers that use labeled variable stars from MACHO, OGLE-III, and ATLAS. In all experiments, ASTROMER-based classifiers outperformed a baseline recurrent neural network trained on light curves directly when limited labeled data was available. Furthermore, using ASTROMER embeddings decreases computational resources needed while achieving state-of-the-art results. Finally, we provide a Python library that includes all the functionalities employed in this work. The library, main code, and pre-trained weights are available at https://github.com/astromer-science