cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Breaking the Barrier for High-Speed in the Interior Permanent Magnet Machine-Slides
Creators: Rukmi Dutta
Publisher: name: IEEE
Year: 2021

TEC Webinar Slides
Abstract: The permanent magnet machines are increasingly used in many emerging applications because of high efficiency and better dynamics, which is pushing the boundary and power of such machines. The applications such as more-electric aircraft and ships, flywheel energy storage, turbo-compressors in automotive applications, and numerous other direct-drive, high-speed industrial applications require simultaneously achieving both high-speed and high-power. Two performance indices rpm kW and tip speed – are often used to quantify the challenges of designing a rotating machine with high speed and power. The interior permanent magnet machine has the lowest rpm kW index indicating greater challenges for this type of machine when designed for high-speed applications. The talk will critically examine the barrier to achieve high-speed in the Interior-type PM machine and the methods to overcome them.
2021 IEEE Workshop on Machine Learning for Power Systems (Slides)
Creators: Fangxing Fran Li
Jin Zhao
Junbo Zhao
Pengwei Du
Spyros Chatzivasileiadis
C.Y. Chung
Anurag K. Srivastava
Publisher: name: IEEE
Year: 2021

Machine Learning (ML) has been one of the emerging areas in the community of electric power systems in recent years. In this workshop, leading experts in this area from research and industrial organizations presented six topics related to machine learning for power systems using various techniques in ML such as convolutional neural networks, deep neural networks, physics-inspired deep learning, and performance guarantee in neural networks. These ML techniques were applied to solve a variety of power grid applications including security assessment, optimization, control, grid reliability, transient stability, and event detection and classifications.
Machine Learning (ML) has been one of the emerging areas in the community of electric power systems in recent years. In this workshop, leading experts in this area from research and industrial organizations presented six topics related to machine learning for power systems using various techniques in ML such as convolutional neural networks, deep neural networks, physics-inspired deep learning, and performance guarantee in neural networks. These ML techniques were applied to solve a variety of power grid applications including security assessment, optimization, control, grid reliability, transient stability, and event detection and classifications.
Symmetry operators and separability of massive Klein-Gordon and Dirac equations in the general 5-dimensional Kerr-(anti-)de Sitter black hole background
Creators: name: Wu, Shuang-Qing
Publisher: name: arXiv
Year: 2008
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: General Relativity and Quantum Cosmology (gr-qc)
subject: High Energy Physics - Phenomenology (hep-ph)
subject: Mathematical Physics (math-ph)
subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: It is shown that the Dirac equation is separable by variables in a five-dimensional rotating Kerr-(anti-)de Sitter black hole with two independent angular momenta. A first order symmetry operator that commutes with the Dirac operator is constructed in terms of a rank-three Killing-Yano tensor whose square is a second order symmetric Stackel-Killing tensor admitted by the five-dimensional Kerr-(anti-)de Sitter spacetime. We highlight the construction procedure of such a symmetry operator. In addition, the first law of black hole thermodynamics has been extended to the case that the cosmological constant can be viewed as a thermodynamical variable.
description: 24 pages, iopart.cls. Published version with references updated
Suzaku Observation of HESS J1825-137: Discovery of Largely-Extended X-rays near from PSR J1826-1334
Creators: name: Uchiyama, H.
name: Matsumoto, H.
name: Tsuru, T. G.
name: Koyama, K.
name: Bamba, A.
Publisher: name: arXiv
Year: 2008
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: We observed the brightest part of HESS J1825-137 with the Suzaku XIS, and found diffuse X-rays extending at least up to 15' (~ 17 pc) from the pulsar PSR J1826-1334. The spectra have no emission line, and are fitted with an absorbed power-law model. The X-rays, therefore, are likely due to synchrotron emission from a pulsar wind nebula. The photon index near at the pulsar (r<1.5') is 1.7 while those in r=1.5-16 are nearly constant at Gamma=2.0. The spectral energy distribution of the Suzaku and H.E.S.S. results are naturally explained by a combined process; synchrotron X-rays and gamma-rays by the inverse Compton of the cosmic microwave photons by high-energy electrons in a magnetic field of 7 micro G. If the electrons are accelerated at the pulsar, the electrons must be transported over 17 pc in the synchrotron life time of 1900 yr, with a velocity of > 8.8 times 10^3 km s^{-1}.
description: 9 pages, 10 figures
Four year observational descriptive study of triplets to ascertain which measures best predict success in primary French immersion
Creators: name: James, Lydia Marie-France
Publisher: name: University of British Columbia
Year: 2010

description: This observational study examines the four-year academic and social development of a set of triplets, one girl and two identical boys attending French immersion. The positive effects this programme has on a child's development are reviewed extensively considering also the learning disabled student. Data for the case study included test results from psychoeducational and informal tests and teachers' ratings. The sample size did not permit a statistical analysis to predict Grade 3 performance in French or English. Cognitive skills, motivation (attitudes, personality traits), and not Kindergarten screening results were predictors of the triplets' success in primary French immersion.
January - Grid Transition Drives Standards Transition
Creators: Doug Houseman
Dan Ernstmann
Austin Arnett
Travis Bouslog and Doug Houseman
Publisher: name: IEEE
Year: 2022

Bulletin
An issue of the Smart Grid Bulletin featuring "Regulations and Standards," "Distributed Generation Grid Compliance and Certifications in US Electric Networks," "CPS Energy Recloser Program is Building a Smart Grid For San Antonio," and "A Question of Standards"
Phase rigidity breaking in open Aharonov-Bohm ring coupled to a cantilever
Creators: name: Romeo, F.
name: Citro, R.
name: Marinaro, M.
Publisher: name: arXiv
Year: 2007
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: The conductance and the transmittance phase shifts of a two-terminal Aharonov-Bohm (AB) ring are analyzed in the presence of mechanical displacements due to coupling to an external can- tilever. We show that phase rigidity is broken, even in the linear response regime, by means of inelastic scattering due to phonons. Our device provides a way of observing continuous variation of the transmission phase through a two-terminal nano-electro-mechanical system (NEMS). We also propose measurements of phase shifts as a way to determine the strength of the electron-phonon coupling in NEMS.
description: 7 pages, 8 figures
Advancement in Machine Learning Aided Power System State Estimation (Slides)
Creators: Junbo Zhao
Ahmed Zamzam
Deepjyoti Deka
Yang Weng
Shikhar Pandey
Publisher: name: IEEE
Year: 2022

With the integration of power electronics-interfaced devices into power systems, it is becoming more and more challenging to develop comprehensive and precise models for power system monitoring and control. This also poses serious challenges for model-based state estimation process. The situation is even worse in distribution systems, where real-time measurements are always insufficient. As a result, fusing multiple sources of data with different granularity and accuracy is becoming critical. This opens the door for leveraging the powerful data-driven Artificial Intelligent technology for power system state estimation. This panel aims to discuss the roles of AI for state estimation and related challenges for practical applications. Use cases will be discussed as well.
With the integration of power electronics-interfaced devices into power systems, it is becoming more and more challenging to develop comprehensive and precise models for power system monitoring and control. This also poses serious challenges for model-based state estimation process. The situation is even worse in distribution systems, where real-time measurements are always insufficient. As a result, fusing multiple sources of data with different granularity and accuracy is becoming critical. This opens the door for leveraging the powerful data-driven Artificial Intelligent technology for power system state estimation. This panel aims to discuss the roles of AI for state estimation and related challenges for practical applications. Use cases will be discussed as well.
Hard QCD probes to quark-gluon plasma
Creators: name: Salgado, Carlos A.
Publisher: name: arXiv
Year: 2007
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: Completely unexplored regimes of QCD, dominated by high-density/temperature effects, are available in heavy ion experiments at collider energies. The successful RHIC program shows how relevant the high transverse momentum part of the spectrum is for the characterization of the properties of the created medium. It points, as well, to interesting properties of the nuclear wave function at small fraction of momentum x, probably dominated by saturated color fields. In both domains, the imminent LHC program will provide a phase space enlarged by orders of magnitude with respect to those studied at RHIC. I will review the present status of hard probes in heavy ion collisions as well as the expectations for the LHC.
description: 8 pages, invited talk at the YKIS Seminar on New Frontiers in QCD
A mathematical proof that the transition to a superconducting state is a second-order phase transition
Creators: name: Watanabe, Shuji
Publisher: name: arXiv
Year: 2008
Subjects: subject: Mathematical Physics (math-ph)
subject: FOS: Physical sciences
subject: 45G10, 82D55

description: We deal with the gap function and the thermodynamical potential in the BCS-Bogoliubov theory of superconductivity, where the gap function is a function of the temperature $T$ only. We show that the squared gap function is of class $C^2$ on the closed interval $[ 0, T_c ]$ and point out some more properties of the gap function. Here, $T_c$ stands for the transition temperature. On the basis of this study we then give, examining the thermodynamical potential, a mathematical proof that the transition to a superconducting state is a second-order phase transition. Furthermore, we obtain a new and more precise form of the gap in the specific heat at constant volume from a mathematical point of view.
description: 16 pages
The effect of story grammar instruction on recall, achievement and comprehension of grade two children
Creators: name: Melnyk, Mary Jo
Publisher: name: University of British Columbia
Year: 2010

description: This study was designed to test the effect of story grammar instruction on the unprompted recall, prompted recall, reading achievement, and comprehension of 165 Grade 2 students in 9 different classes within the Catholic School System. Classes were randomly assigned to one of three conditions: story grammar instruction (based on story structure) modified reading instruction (researcher designed) or regular reading instruction (classroom teacher's method). Pretests for vocabulary, recall and reading achievement were administered and data were collected on age, sex, socioeconomic status and language skills. Reading programs, including ability groupings, reading material, word skills and vocabulary instruction were altered as little as possible in an attempt to preserve usual classroom routines. Researcher designed seatwork activities were given to the story grammar and modified reading groups to help the researcher monitor the story grammar method and maintain the equality of researcher intervention between story grammar and modified reading. The study continued for eleven weeks. Analysis of covariance, used to test the effect of method, class (nested within method) and sex showed no significant effects for any posttest due to method. However, for the Unprompted Recall test, girls scored significantly higher than boys. Further analyses of covariance, testing the effect of method, class (nested within method) and ability, again indicated no significant main effects for method. However, ability was significant in each posttest with good readers scoring higher than poor readers. In addition, method interacted with ability for the Prompted Recall Detail posttest, indicating that poor readers receiving story grammar instruction scored significantly lower than good readers in any of the three methods. In contrast, poor readers receiving modified or regular reading did not have a score signficantly different from good readers. Method again interacted with ability for the Achievement posttest. Poor readers receiving either story grammar or modified reading instruction scored significantly lower than good readers in any of the three methods. In contrast, poor readers receiving regular reading did not have a score significantly different from good readers. These results differ from those found in previous studies and therefore cannot provide support for story grammar instruction with Grade 2 students. This study concludes with a discussion of the variables within the study design which may have adversely affected the results. Recommendations for refinements in study design to control for these factors are made.
CADE Relatorio de atividades
Creators: name: Alexandre Cordeiro Macedo
name: Paulo Eduardo Silva de Oliveira
name: Vinicius Eloy dos Reis
name: William José da Conceição Marques
name: Leonardo de Oliveira Alves Sanches Lima
name: Alessandro Lustosa Seixas Pinheiro
name: Cristiane de Freitas Leal
name: Felipe Alberto Moreira
name: Helio Ribeiro da Costa
name: Jorge Luiz Hachem Vasconcelos
name: Wendel Sousa de Anchieta
name: Márcia Abrahão Moura
name: Maria Emília Machado Telles Walter
name: Rafael Timóteo de Sousa Júnior
name: Edna Dias Canedo
name: Georges Daniel Amvame Nze
name: Valério Aymore Martins
name: Adailton Amaro Nunes
name: Alessandra Sales
name: Aline Lima da Silva
name: Ana Beatriz
name: Ana Flavia Araujo Santana
name: André Luiz Chaves da Silva
name: Bruno Justino Garcia Praciano
name: Caroline Sousa
name: Danilo Freire Holanda de Paiva
name: Denise Mitie Taketomi
name: Edle Marcio dos Santos Silva
name: Eduardo Drumond Soares
name: Felipe Evangelista
name: Guilherme Pereira Paiva
name: Hugo Bartolomeu Ferreira
name: Igor de Almeida Gentil
name: Isabela Carolina Martins
name: Italo Frota
name: Izadora Oliveira Linhares
name: Jeanne Louize Emygdio
name: Karen Ferreira Machado
name: Lohana Salustiano Cardoso
name: Luiz Fernando Santos de Araujo Caduda
name: Marcelo Dos Santos Vianna
name: Marcio Junior Vieira
name: Marcos Vinicius da Silva Souza
name: Mateus Alves Dantas
name: Noely Gomes de Lima
name: Paulo Henrique Batista Rodrigues
name: Rafael Faria
name: Renato Carauta Ribeiro
name: Thays de Oliveira Coelho
name: Thiago Augusto Montenegro Pestana
name: Vanessa Coelho Ribeiro
Publisher: name: Zenodo
Year: 2022

description: Pesquisa Aplicada com fundamento no estudo de necessidades, análise informacional, concepção, prototipação e experimentação com vistas à inovação tecnológica e de processos no domínio da Defesa Econômica para o Conselho Administrativo de Defesa Econômica – Cade.
Global Optimal Solution to Profit-Maximizing AC Optimal Power Flow Problem
Creators: Amro M. Farid
Publisher: name: IEEE
Year: 2022

An interview with Amro M. Farid about Global Optimal Solution to Profit-Maximizing AC Optimal Power Flow Problem
In the December 2021 issue, IEEE Access published a globally optimal solution to the AC Optimal Power Problem in an open-access article entitled: “A Profit-Maximizing Security-Constrained IV-AC Optimal Power Flow Model & Global Solution” authored by Prof. Amro M. Farid.
Vicinal silicon surfaces: from step density wave to faceting
Creators: name: Leroy, F.
name: Muller, P.
name: Metois, J. J.
name: Pierre-Louis, O.
Publisher: name: arXiv
Year: 2007
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: This paper investigates faceting mechanisms induced by electromigration in the regime where atomic steps are transparent. For this purpose we study several vicinal orientations by means of in-situ (optical diffraction, electronic microscopy) as well as ex-situ (AFM, microprofilometry) visualization techniques. The data show that faceting proceeds in two stages. The first stage is short and leads to the appearance of a step density wave, with a wavelength roughly independent of the surface orientation. The second stage is much slower, and leads to the formation of a hill-and-valley structure, the period of which depends on the initial surface orientation. A simple continuum model enables us to point out why the wavelength of the step density wave does not depend on the microscale details of the surface. The final wavelength is controlled by the competition between elastic step-step interaction and facet edge energy cost. Finally, the surface stress angular dependence is shown to emerge as a coarsed-grained picture from the step model.
description: 26 pages, 9 figures
June - Power Quality and System Reliability
Creators: Marco Jung
Sebastian Sprunk
and Bikash Sah
Math Bollen and Zunaira Nazir
Adel El-Shahat
Appala Naidu Talada
Tareg Ghaoud
and Sajan Kaduvettykunnal Sadanandan
Vikash Kumar Saini
Shashank Vyas
Sujil A
and Rajesh Kumar
Publisher: name: IEEE
Year: 2022

Bulletin
An issue of the Smart Grid Bulletin featuring "Reliability in power electronic systems: A hierarchical approach," "Operational risk assessment – time for a smarter look at reliability for power transmission systems," "Enhanced Solar Cells Efficiency Approach for Smart Grids Applications," "Importance of Power Quality in Grid-connected PV Systems," and "A Secure Energy Transaction Platform for Prosumers in a Smart Community"
Inégalités de Poincaré cinétiques
Creators: name: Azerad, Pascal
name: Brull, Stéphane
Publisher: name: arXiv
Year: 2008
Subjects: subject: Analysis of PDEs (math.AP)
subject: FOS: Mathematics

description: In this note we prove Poincaré type inequalities for a family of kinetic equations. We apply this inequality to the variational solution of a linear kinetic model.
New interactions in the dark sector mediated by dark energy
Creators: name: Brookfield, A. W.
name: van de Bruck, C.
name: Hall, L. M. H.
Publisher: name: arXiv
Year: 2007
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: Cosmological observations have revealed the existence of a dark matter sector, which is commonly assumed to be made up of one particle species only. However, this sector might be more complicated than we currently believe: there might be more than one dark matter species (for example two components of cold dark matter or a mixture of hot and cold dark matter) and there may be new interactions between these particles. In this paper we study the possibility of multiple dark matter species and interactions mediated by a dark energy field. We study both the background and the perturbation evolution in these scenarios. We find that the background evolution of a system of multiple dark matter particles (with constant couplings) mimics a single fluid with a time-varying coupling parameter. However, this is no longer true on the perturbative level. We study the case of attractive and repulsive forces as well as a mixture of cold and hot dark matter particles.
description: 10 pages, 17 figs, revtex, Version published in PRD, typo corrected, references added
Nonlinear Schrodinger Equations and N=2 Superconformal Algebra
Creators: name: Ozer, H. T.
Publisher: name: arXiv
Year: 2008
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: Mathematical Physics (math-ph)
subject: FOS: Physical sciences

description: We obtain new coupled super Nonlinear Schrodinger equations by using AKNS scheme and soliton connection taking values in N=2 superconformal algebra.
description: 12 pages, no figures, LaTex file; http://www.internonlinearscience.org/upload/papers/20110618052032246.pdf
BICEP/Keck and Cosmological Attractors
Creators: name: Kallosh, Renata
name: Linde, Andrei
Publisher: name: arXiv
Year: 2021
Subjects: subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: General Relativity and Quantum Cosmology (gr-qc)
subject: High Energy Physics - Phenomenology (hep-ph)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: We discuss implications of the latest BICEP/Keck data release for inflationary models, with special emphasis on the cosmological attractors which can describe all presently available inflation-related observational data. These models are compatible with any value of the tensor to scalar ratio $r$, all the way down to $r = 0$. Some of the string theory motivated models of this class predict $10^{-3} \leq r \leq 10^{-2}$. The upper part of this range can be explored by the ongoing BICEP/Keck observations.
description: 14 pages, 10 figures. A figure added with a comparison of the new constraints on r and $n_s$ given in 2112.07961 and predictions of $\alpha$-attractors
The role of the slope of `realistic' potential barriers in preventing relativistic tunnelling in the Klein zone
Creators: name: Christillin, Paolo
name: d'Emilio, Emilio
Publisher: name: arXiv
Year: 2007
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: The transmission of fermions of mass m and energy E through an electrostatic potential barrier of rectangular shape (i.e. supporting an infinite electric field), of height U> E + m - due to the many-body nature of the Dirac equation evidentiated by the Klein paradox - has been widely studied. We exploit here the analytical solution, given by Sauter for the linearly rising potential step, to show that the tunnelling rate through a more realistic trapezoidal barrier is exponentially depressed, as soon as the length of the regions supporting a finite electric field exceeds the Compton wavelenght of the particle - the latter circumstance being hardly escapable in most realistic cases.
A tactile closed-loop device for musical interaction
Creators: name: de Jong, Staas
Publisher: name: arXiv
Year: 2021
Subjects: subject: Human-Computer Interaction (cs.HC)
subject: FOS: Computer and information sciences
subject: H.5.5

description: This paper presents a device implementing a closed tactile loop for musical interaction, based on a small freely held magnet which serves as the medium for both input and output. The component parts as well as an example of its programmable behaviour are described.
description: Proceedings of the International Conference on New Interfaces for Musical Expression, 2006
The Hall conductance, topological quantum phase transition and the Diophantine equation on honeycomb lattice
Creators: name: Sato, Masatoshi
name: Tobe, Daijiro
name: Kohmoto, Mahito
Publisher: name: arXiv
Year: 2008
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: We consider a tight-binding model with the nearest neighbour hopping integrals on the honeycomb lattice in a magnetic field. Assuming one of the three hopping integrals, which we denote t_a, can take a different value from the two others, we study quantum phase structures controlled by the anisotropy of the honeycomb lattice.For weak and strong t_a regions, respectively, the Hall conductances are calculated algebraically by using the Diophantine equation. Except for a few specific gaps, we completely determine the Hall conductances in these two regions including those for subband gaps. In a weak magnetic field, it is found that the weak t_a region shows the unconventional quantization of the Hall conductance, σ_{xy}=-(e^2/h)(2n+1), (n=0,\pm 1,\pm 2,...), near the half-filling, while the strong t_a region shows only the conventional one, σ_{xy}=-(e^2/h)n,(n=0,1,2,...). From topological nature of the Hall conductance, the existence of gap closing points and quantum phase transitions in the intermediate t_a region are concluded. We also study numerically the quantum phase structure in detail, and find that even when t_a=1, namely in graphene case, the system is in the weak t_a phase except when the Fermi energy is located near the van Hove singularity or the lower and upper edges of the spectrum.
description: 35 pages, 15 figures; added references
Hypernuclei and in-medium chiral dynamics
Creators: name: Finelli, P.
Publisher: name: arXiv
Year: 2007
Subjects: subject: Nuclear Theory (nucl-th)
subject: FOS: Physical sciences

description: A recently introduced relativistic nuclear energy density functional, constrained by features of low-energy QCD, is extended to describe the structure of hypernuclei. The density-dependent mean field and the spin-orbit potential of a $Λ$-hyperon in a nucleus, are consistently calculated using the SU(3) extension of in-medium chiral perturbation theory. The leading long-range $ΛN$ interaction arises from kaon-exchange and $2π$-exchange with a $Σ$-hyperon in the intermediate state. Scalar and vector mean fields, originating from in-medium changes of the quark condensates, produce a sizeable {\em short-range} spin-orbit interaction. The model, when applied to oxygen as a test case, provides a natural explanation for the smallness of the effective $Λ$ spin-orbit potential: an almost complete cancellation between the background contributions (scalar and vector) and the long-range terms generated by two-pion exchange.
description: 8 pages and 6 figures. To appear in the proceedings of the Theoretical nuclear physics school "Exotic Nuclei: New Challenges", Les Houches (France) May 7-18, 2007
An exploratory study of the hypothesis of divisible versus unitary competence in second language proficiency
Creators: name: Barbour, Ross Patrick
Publisher: name: University of British Columbia
Year: 2010

description: In this research Oiler's question 'Is language proficiency divisible into components?' was explored by determining which of three models best fit the experimental data: a model postulating numerous specific sources of variance (the extreme divisible model), a model postulating a single, large source of variance (the unitary model), or a model postulating a large general factor and several smaller specific factors. Following analysis of data gathered in a preliminary study, four tests which had clearly recognizable contrasts in content (grammar vs. vocabulary) and mode (listening vs. reading) were constructed to identify linguistic and method variance in a correlation matrix of language proficiency variables. These four measures were pilot tested, revised, and administered in conjunction with eight other language measures to a group of beginning-level ESL learners. The data were factor analyzed using image analysis to explore the relative congruency of the three models to the data. In addition, the relationships between the tests and the demographic variables age, sex, length of time in English Canada, and first language were also investigated. In the factor analysis, both of the methods used to determine the number of factors to be retained in the final solution indicated three. (The methods used were the Kaiser-Guttman criterion of selecting factors with eigen values greater than one in a principal components analysis and the inspection of a varimax rotation of a full image analysis to determine the first factor with negligible coefficients.) When transformed using a Harris-Kaiser oblique transformation (Independent Clusters), the data presented evidence for a grammar factor, a vocabulary factor and an age-related factor which may be linked closely to the hearing ability of the students. In addition, the analyses suggested the possibility that a listening-mode factor and what I have termed a 'speed of processing factor' were also influencing the variables. The factors, however, were highly correlated, suggesting the presence of a strong general factor underlying all of the measures. The analyses of the specific relationships between each of four demographic variables (age, sex, first language, and the length of time the subject had been in Canada) and each of the twelve language variables revealed a strong negative correlation between the language measures and two of the demographic variables, age and length of time in Canada. In addition, this set of analyses revealed that the Chinese as a group performed differently than non-Chinese as a group. The analysis of sex produced no significant findings. The conclusion of the study was that the language proficiency data in this study was best modelled by a large general factor and two specific, content-related factors, grammar and vocabulary. The possibility of specific factors related to mode was not ruled out.
Energy-stable discretization of two-phase flows in deformable porous media with frictional contact at matrix-fracture interfaces
Creators: name: Bonaldi, Francesco
name: Droniou, Jérôme
name: Masson, Roland
name: Pasteau, Antoine
Publisher: name: arXiv
Year: 2021
Subjects: subject: Numerical Analysis (math.NA)
subject: FOS: Mathematics
subject: 65M12, 76S05, 74B10, 74M15

description: We address the discretization of two-phase Darcy flows in a fractured and deformable porous medium, including frictional contact between the matrix-fracture interfaces. Fractures are described as a network of planar surfaces leading to the so-called mixed- or hybrid-dimensional models. Small displacements and a linear elastic behavior are considered for the matrix. Phase pressures are supposed to be discontinuous at matrix-fracture interfaces, as they provide a better accuracy than continuous pressure models even for high fracture permeabilities. The general gradient discretization framework is employed for the numerical analysis, allowing for a generic stability analysis and including several conforming and nonconforming discretizations. We establish energy estimates for the discretization, and prove existence of a solution. To simulate the coupled model, we employ a Two-Point Flux Approximation (TPFA) finite volume scheme for the flow and second-order ($\mathbb P_2$) finite elements for the mechanical displacement coupled with face-wise constant ($\mathbb P_0$) Lagrange multipliers on fractures, representing normal and tangential stresses, to discretize the frictional contact conditions. This choice allows to circumvent possible singularities at tips, corners, and intersections between fractures, and provides a local expression of the contact conditions. We present numerical simulations of two benchmark examples and one realistic test case based on a drying model in a radioactive waste geological storage structure.
Quantum behavior of the dc SQUID phase qubit
Creators: name: Mitra, Kaushik
name: Strauch, F. W.
name: Lobb, C. J.
name: Anderson, J. R.
name: Wellstood, F. C.
name: Tiesinga, Eite
Publisher: name: arXiv
Year: 2008
Subjects: subject: Superconductivity (cond-mat.supr-con)
subject: Other Condensed Matter (cond-mat.other)
subject: FOS: Physical sciences

description: We analyze the behavior of a dc Superconducting Quantum Interference Device (SQUID) phase qubit in which one junction acts as a phase qubit and the rest of the device provides isolation from dissipation and noise in the bias leads. Ignoring dissipation, we find the two-dimensional Hamiltonian of the system and use numerical methods and a cubic approximation to solve Schrodinger's equation for the eigenstates, energy levels, tunneling rates, and expectation value of the currents in the junctions. Using these results, we investigate how well this design provides isolation while preserving the characteristics of a phase qubit. In addition, we show that the expectation value of current flowing through the isolation junction depends on the state of the qubit and can be used for non-destructive read out of the qubit state.
description: 38 pages, 7 figures
Modular invariant holographic correlators for $\mathcal{N}=4$ SYM with general gauge group
Creators: name: Alday, Luis F.
name: Chester, Shai M.
name: Hansen, Tobias
Publisher: name: arXiv
Year: 2021
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: We study the stress tensor four-point function for $\mathcal{N}=4$ SYM with gauge group $G=SU(N)$, $SO(2N+1)$, $SO(2N)$ or $USp(2N)$ at large $N$. When $G=SU(N)$, the theory is dual to type IIB string theory on $AdS_5\times S^5$ with complexified string coupling $τ_s$, while for the other cases it is dual to the orbifold theory on $AdS_5\times S^5/\mathbb{Z}_2$. In all cases we use the analytic bootstrap and constraints from localization to compute 1-loop and higher derivative tree level corrections to the leading supergravity approximation of the correlator. We give perturbative evidence that the localization constraint in the large $N$ and finite complexified coupling $τ$ limit can be written for each $G$ in terms of Eisenstein series that are modular invariant in terms of $τ_s\proptoτ$, which allows us to fix protected terms in the correlator in that limit. In all cases, we find that the flat space limit of the correlator precisely matches the type IIB S-matrix. We also find a closed form expression for the $SU(N)$ 1-loop Mellin amplitude with supergravity vertices. Finally, we compare our analytic predictions at large $N$ and finite $τ$ to bounds from the numerical bootstrap in the large $N$ regime, and find that they are not saturated for any $G$ and any $τ$, which suggests that no physical theory saturates these bootstrap bounds.
description: 58 pages, 3 figures, v2: clarifications about USp(2N), include numerical bootstrap data, v3: clarifications about modular invariance, include 1-loop Mellin amplitude in ancillary file, v4: JHEP version, v5: add journal ref
Gamma-Rays from Decaying Dark Matter
Creators: name: Bertone, Gianfranco
name: Buchmuller, Wilfried
name: Covi, Laura
name: Ibarra, Alejandro
Publisher: name: arXiv
Year: 2007
Subjects: subject: Astrophysics (astro-ph)
subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: We study the prospects for detecting gamma-rays from decaying Dark Matter (DM), focusing in particular on gravitino DM in R-parity breaking vacua. Given the substantially different angular distribution of the predicted gamma-ray signal with respect to the case of annihilating DM, and the relatively poor (of order 0.1$^\circ$) angular resolution of gamma-ray detectors, the best strategy for detection is in this case to look for an exotic contribution to the gamma-ray flux at high galactic latitudes, where the decaying DM contribution would resemble an astrophysical extra-galactic component, similar to the one inferred by EGRET observations. Upcoming experiments such as GLAST and AMS-02 may identify this exotic contribution and discriminate it from astrophysical sources, or place significant constraints on the mass and lifetime of DM particles.
description: 15 pages, 5 figures, LaTeX with iopart.cls. Minor changes, typos corrected and references added/updated. Version accepted for publication in JCAP
Absence of Triangles in Maximal Supergravity Amplitudes
Creators: name: Bjerrum-Bohr, N. E. J.
name: Vanhove, Pierre
Publisher: name: arXiv
Year: 2008
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: From general arguments, we show that one-loop n-point amplitudes in colourless theories satisfy a new type of reduction formula. These lead to the existence of cancellations beyond supersymmetry. Using such reduction relations we prove the no-triangle hypothesis in maximal supergravity by showing that in four dimensions the n-point graviton amplitude contain only scalar box integral functions. We also discuss the reduction formulas in the context of gravity amplitudes with less and no supersymmetry.
description: 23 pages, RevTeX4 format. v2: Expanded version with a new section providing some extra background material and an overview of the general arguments. Minors typos have been corrected. Version to be published
Generalizing the Tomboulis-Yaffe Inequality to SU(N) Lattice Gauge Theories and General Classical Spin Systems
Creators: name: Kanazawa, Takuya
Publisher: name: arXiv
Year: 2008
Subjects: subject: Mathematical Physics (math-ph)
subject: Statistical Mechanics (cond-mat.stat-mech)
subject: High Energy Physics - Lattice (hep-lat)
subject: FOS: Physical sciences
subject: 81T25, 82B20

description: We extend the inequality of Tomboulis and Yaffe in SU(2) lattice gauge theory (LGT) to SU(N) LGT and to general classical spin systems, by use of reflection positivity. Basically the inequalities guarantee that a system in a box that is sufficiently insensitive to boundary conditions has a non-zero mass gap. We explicitly illustrate the theorem in some solvable models. Strong coupling expansion is then utilized to discuss some aspects of the theorem. Finally a conjecture for exact expression to the off-axis mass gap of the triangular Ising model is presented. The validity of the conjecture is tested in multiple ways.
description: 37 pages, 17 figures. v2: comment on an earlier work included after conclusion, figure 2 corrected. v3: the latter half revised significantly with new results and new discussions, the version to appear in Ann. Phys.
The cyclotactor: towards a tactile platform for musical interaction
Creators: name: de Jong, Staas
Publisher: name: arXiv
Year: 2021
Subjects: subject: Human-Computer Interaction (cs.HC)
subject: Sound (cs.SD)
subject: Audio and Speech Processing (eess.AS)
subject: FOS: Computer and information sciences
subject: FOS: Electrical engineering, electronic engineering, information engineering
subject: H.5.5

description: This paper reports on work in progress on a finger-based tactile I/O device for musical interaction. Central to the device is the ability to set up cyclical relationships between tactile input and output. A direct practical application of this to musical interaction is given, using the idea to multiplex two degrees of freedom on a single tactile loop.
description: Proceedings of the International Conference on New Interfaces for Musical Expression, 2008
Day-Ahead Electricity Demand Forecasting Competition: Post-COVID Paradigm
Creators: Mostafa Farrokhabadi
Jethro Browell
Yi Wang
Stephen Makonin
Wencong Su
and Hamidreza Zareipour
Publisher: name: IEEE
Year: 2022

This paper presents the findings of the "IEEE DataPort Day-Ahead Electricity Demand Forecasting Competition: Post-COVID Paradigm" from the technical and organizational perspectives.
The COVID-19 related shutdowns have made significant impacts on the electric grid operation worldwide. The global electrical demand plummeted around the planet in 2020 continuing into 2021. Moreover, demand shape has been profoundly altered as a result of industry shutdowns, business closures, and people working from home. In view of such massive electric demand changes, energy forecasting systems struggle to provide an accurate demand prediction, exposing operators to technical and financial risks, and further reinforcing the adverse economic impacts of the pandemic. In this context, the "IEEE DataPort Day-Ahead Electricity Demand Forecasting Competition: Post-COVID Paradigm" was organized to support the development and dissemination state-of-the-art load forecasting techniques that can mitigate the adverse impact of pandemic-related demand uncertainties. This paper presents the findings of this competition from the technical and organizational perspectives. The competition structure and participation statistics are provided, and the winning methods are summarized. Furthermore, the competition dataset and problem formulation is discussed in detail. Finally, the dataset is published along with this paper for reproducibility and further research.
$\mathcal{O}$-operators on Lie $\infty$-algebras with respect to Lie $\infty$-actions
Creators: name: Caseiro, R.
name: da Costa, J. Nunes
Publisher: name: arXiv
Year: 2021
Subjects: subject: Rings and Algebras (math.RA)
subject: Mathematical Physics (math-ph)
subject: Differential Geometry (math.DG)
subject: FOS: Mathematics
subject: FOS: Physical sciences
subject: 17B10, 17B40, 17B70, 55P43

description: We define $\mathcal{O}$-operators on a Lie $\infty$-algebra $E$ with respect to an action of $E$ on another Lie $\infty$-algebra and we characterize them as Maurer-Cartan elements of a certain Lie $\infty$-algebra obtained by Voronov's higher derived brackets construction. The Lie $\infty$-algebra that controls the deformation of $\mathcal{O}$-operators with respect to a fixed action is determined.
Reduction leaching of chalcopyrite
Creators: name: Hackl, Ralph Peter
Publisher: name: University of British Columbia
Year: 2010

description: This study has been concerned with developing novel reduction leach methods for chalcopyrite (CuFeS₂) copper concentrates. It has been found that chalcopyrite can be essentially completely converted to chalcocite (Cu₂S) by leaching in strong copper sulphate solutions at elevated temperatures, using either pressurized hydrogen gas or metallic copper powder as reductants. The essential leach reactions appear to obey the following overall stoichiometry: CuFeS₂ + 3Cu²⁺ + 2H₂ → 2Cu₂S + Fe²⁺ + 4H⁺; CuFeS₂ + Cu²⁺ + 2Cu° → 2Cu₂S + Fe²⁺. Reaction rates are increased by increasing leach temperature, decreasing concentrate and copper powder particle size, and the presence of a cuprous-stabilizing agent. The sulphide minerals bornite (Cu₅FeS₄) and pyrite (FeS₂), comnonly found in copper concentrates, are also quantitatively converted by reduction leaching under these conditions. Microscopic evidence indicates that chalcocite forms as layers which crack and spall away from the reacting sulphides, allowing complete extraction of iron to take place. The mechanism for reaction probably involves transport of cuprous ions both in aqueous solution and in the solid state (Cu₂S), and solid state diffusion of iron outward. Cuprous ions are formed as an intermediate species during the leach, either by reaction of cupric ions with hydrogen or with copper metal. This species then probably reacts with the chalcopyrite mineral as follows: CuFeS₂ + 4Cu⁺ → 2Cu₂S + Fe²⁺ + Cu²⁺. Potential methods of incorporating reduction leaching into a hydrometallurgical process for treating copper concentrates are discussed.
Testing the galaxy cluster mass-observable relations at z = 1 with XMM-Newton and Chandra observations of XLSSJ022403.9-041328
Creators: name: Maughan, B. J.
name: Jones, L. R.
name: Pierre, M.
name: Andreon, S.
name: Birkinshaw, M.
name: Bremer, M. N.
name: Pacaud, F.
name: Ponman, T. J.
name: Valtchanov, I.
name: Willis, J.
Publisher: name: arXiv
Year: 2007
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: We present an analysis of deep XMM-Newton and Chandra observations of the z=1.05 galaxy cluster XLSSJ022403.9-041328 (hereafter XLSSC 029), detected in the XMM-Newton large scale structure survey. Density and temperature profiles of the X-ray emitting gas were used to perform a hydrostatic mass analysis of the system. This allowed us to measure the total mass and gas fraction in the cluster and define overdensity radii R500 and R2500. The global properties of XLSSC 029 were measured within these radii and compared with those of the local population. The gas mass fraction was found to be consistent with local clusters. The mean metal abundance was 0.18 +0.17 -0.15 Zsol, with the cluster core regions excluded, consistent with the predicted and observed evolution. The properties of XLSSC 029 were then used to investigate the position of the cluster on the M-kT, YX-M, and LX-M scaling relations. In all cases the observed properties of XLSSC 029 agreed well with the simple self-similar evolution of the scaling relations. This is the first test of the evolution of these relations at z > 1 and supports the use of the scaling relations in cosmological studies with distant galaxy clusters.
description: 11 pages, 11 figures. Accepted for publication in MNRAS. Revised to include treatment of XMM PSF. Conclusions unchanged
Human Mobility-Based Features to Analyse the Impact of COVID-19 on Power System Operation of Ireland
Creators: Negin Zarbakhsh
M. Saeed Misaghian
and Gavin McArdle
Publisher: name: IEEE
Year: 2022

This paper proposes an analytical framework to assess the impact of COVID-19 on power system operation as well as day-ahead electricity prices in Ireland.
COVID-19 non-pharmaceutical interventions (NPIs) are changing human mobility patterns; however, the effects on power systems remain unclear. Previous loads and timings along with weather features are often used in literature as input features in load forecasting, but these may be insufficient during COVID-19. As a result, this paper proposes an analytical framework to assess the impact of COVID-19 on power system operation as well as day-ahead electricity prices in Ireland. To improve peak demand forecasting during pandemics, we incorporate mobility, NPIs, and COVID-19 cases as complementary input features and representative of human behaviour changes. By defining different combinations of these explanatory features, several Machine Learning (ML) algorithms are applied and their performance is compared with the baseline scenario currently used in the literature. Using SHapley Additive Explanations (SHAP), we interpret the best performing model, Light Gradient Boosted Machine, to determine the influence of each feature on the predicted outcomes. We discover that typical load forecasting features still influence ML outcomes the most, but mobility-related changes are also significant. Our finding shows that NPIs impact human behaviour and electricity consumption during times of crisis and can be used in the context of load forecasting to assist policymakers and energy distributors.
Topological objects in QCD
Creators: name: Bruckmann, Falk
Publisher: name: arXiv
Year: 2007
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: High Energy Physics - Lattice (hep-lat)
subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: Topological excitations are prominent candidates for explaining nonperturbative effects in QCD like confinement. In these lectures, I cover both formal treatments and applications of topological objects. The typical phenomena like BPS bounds, topology, the semiclassical approximation and chiral fermions are introduced by virtue of kinks. Then I proceed in higher dimensions with magnetic monopoles and instantons and special emphasis on calorons. Analytical aspects are discussed and an overview over models based on these objects as well as lattice results is given.
description: 28 pages, 17 figures; Lectures given at 45th Internationale Universitaetswochen fuer Theoretische Physik (International University School of Theoretical Physics): Conceptual and Numerical Challenges in Femto- and Peta-Scale Physics, Schladming, Styria, Austria, 24 Feb - 3 Mar 2007