cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
A Numerical Treatment of the Rf SQUID: II. Noise Temperature
Creators: name: Kleiner, Reinhold
name: Koelle, Dieter
name: Clarke, John
Publisher: name: arXiv
Year: 2007
Subjects: subject: Superconductivity (cond-mat.supr-con)
subject: FOS: Physical sciences

description: We investigate rf SQUIDs (Superconducting QUantum Interference Devices), coupled to a resonant input circuit, a readout tank circuit and a preamplifier, by numerically solving the corresponding Langevin equations and optimizing model parameters with respect to noise temperature. We also give approximate analytic solutions for the noise temperature, which we reduce to parameters of the SQUID and the tank circuit in the absence of the input circuit. The analytic solutions agree with numerical simulations of the full circuit to within 10%, and are similar to expressions used to calculate the noise temperature of dc SQUIDs. The best device performance is obtained when β_L'\equiv 2πL I_0Φ_0 is 0.6 - 0.8; L is the SQUID inductance, I_0 the junction critical current and Φ_0 the flux quantum. For a tuned input circuit we find an optimal noise temperature T_{N,opt}\approx 3Tf/f_c, where T, f and f_c denote temperature, signal frequency and junction characteristic frequency, respectively. This value is only a factor of 2 larger than the optimal noise temperatures obtained by approximate analytic theories carried out previously in the limit β_L'<<1. We study the dependence of the noise temperature on various model parameters, and give examples using realistic device parameters of the extent to which the intrinsic noise temperature can be realized experimentally.
description: submitted to J. Low Temp. Phys
The Spectrum of the Fractional Laplacian and First Passage Time Statistics
Creators: name: Katzav, E.
name: Adda-Bedia, M.
Publisher: name: arXiv
Year: 2008
Subjects: subject: Statistical Mechanics (cond-mat.stat-mech)
subject: Disordered Systems and Neural Networks (cond-mat.dis-nn)
subject: Soft Condensed Matter (cond-mat.soft)
subject: FOS: Physical sciences

description: We present exact results for the spectrum of the fractional Laplacian in a bounded domain and apply them to First Passage Time (FPT) Statistics of Lévy flights. We specifically show that the average is insufficient to describe the distribution of FPT, although it is the only quantity available in the existing literature. In particular, we show that the FPT distribution is not peaked around the average, and that knowledge of the whole distribution is necessary to describe this phenomenon. For this purpose, we provide an efficient method to calculate higher order cumulants and the whole distribution.
description: 10 pages, 6 figures
Temperature-dependent pulsations of superfluid neutron stars
Creators: name: Gusakov, M. E.
name: Andersson, N.
Publisher: name: arXiv
Year: 2006
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: We examine radial oscillations of superfluid neutron stars at finite internal temperatures. For this purpose we generalize the description of relativistic superfluid hydrodynamics to the case of superfluid mixtures. We show that in a neutron star at hydrostatic and beta-equilibrium the red-shifted temperature gradient is smoothed out by neutron superfluidity (but not by proton superfluidity). We calculate radial oscillation modes of neutron stars assuming "frozen" nuclear composition in the pulsating matter. The resulting pulsation frequencies show a strong temperature dependence in the temperature range (0.1-1) T_cn, where T_cn is the critical temperature of neutron superfluidity. Combining our results with thermal evolution, we obtain a significant evolution of the pulsation spectrum, associated with highly efficient Cooper pairing neutrino emission, for 20 years after superfluidity onset.
description: 29 pages, 1 table, 4 figures
Turbulence and Particle Acceleration in Shearing Flows
Creators: name: Rieger, Frank M.
name: Duffy, Peter
Publisher: name: arXiv
Year: 2021
Subjects: subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: FOS: Physical sciences

description: We explore constraints imposed by shear-driven instabilities on the acceleration of energetic particles in relativistic shearing flows. We show that shearing layers in large-scale AGN jets are likely to encompass a sizeable fraction ($\geq 0.1$) of the jet radius, requiring seed injection of GeV electrons for efficient acceleration. While the diffusion process may depend on pre-developed turbulence if injection occurs at higher energies, electron acceleration to PeV and proton acceleration to EeV energies appears possible within the constraints imposed by jet stability.
description: 6 pages, 2 figures; ApJL to appear
High-resolution imaging of the cosmic mass distribution from gravitational lensing of pregalactic HI
Creators: name: Metcalf, R. Benton
name: White, S. D. M.
Publisher: name: arXiv
Year: 2006
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: Low-frequency radio observations of neutral hydrogen during and before the epoch of cosmic reionization will provide ~ 1000 quasi-independent source planes, each of precisely known redshift, if a resolution of ~1 arcminutes or better can be attained. These planes can be used to reconstruct the projected mass distribution of foreground material. Structure in these source planes is linear and gaussian at high redshift (30~ 10 MHz should be able to make mass maps of high quality. The planned Square Kilometer Array (SKA) may be able to map the mass with moderate signal-to-noise down to arcminute scales, depending on the reionization history of the universe and the ability to subtract foreground sources.
description: revised and extended, more detailed predictions for observations, 25 pages, 11 figures, submitted to MNRAS
Indium Antimonide, constraints on practicality as a magneto-optical platform for topological surface plasmon polaritons
Creators: name: Pakniyat, Samaneh
name: Liang, Yi
name: Xiang, Yinxiao
name: Cen, Cheng
name: Chen, Jun
name: Hanson, George W.
Publisher: name: arXiv
Year: 2020
Subjects: subject: Optics (physics.optics)
subject: Applied Physics (physics.app-ph)
subject: FOS: Physical sciences

description: Magnetic-field-biased indium antimonide (InSb) is one of the most widely-discussed materials for supporting nonreciprocal surface plasmon polaritons (SPPs), which have recently been shown to be topological. In this work, we provide a critical assessment of InSb as a magneto-optical SPP platform, and show that it is only viable under a narrow set of conditions.
description: 6 pages, 4 figures and 2 tables
Linear Response Theory and the Universal Nature of the Magnetic Excitation Spectrum of the Cuprates
Creators: name: Norman, M. R.
Publisher: name: arXiv
Year: 2007
Subjects: subject: Superconductivity (cond-mat.supr-con)
subject: FOS: Physical sciences

description: Linear response theory, commonly known as the random phase approximation (RPA), predicts a rich magnetic excitation spectrum for d-wave superconductors. Many of the features predicted by such calculations appear to be reflected in inelastic neutron scattering data of the cuprates. In this article, I will present results from RPA calculations whose input is based on angle resolved photoemission data, and discuss possible relevance to inelastic neutron scattering data of LSCO, YBCO, and Bi2212 in their superconducting and non-superconducting phases. In particular, the question of the universality of the magnetic excitation spectrum will be addressed.
description: 9 pages, 13 figures
Strong and Electromagnetic Mass Splittings in Heavy Mesons
Creators: name: Goity, Jose L.
name: Jayalath, Chandana P.
Publisher: name: arXiv
Year: 2007
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: The contributions to heavy meson mass differences by the strong hyperfine interaction, the light quark masses and the electromagnetic interaction are obtained from the empirical values of the $D$, $D^*$, $B$ and $B^*$ masses by means of a mass formula based on the heavy quark mass expansion. The three different types of contributions are determined with significant accuracy to next to leading order in that expansion.
description: 12 pages, 2 figures
On the scaling of the damping time for resonantly damped oscillations in coronal loops
Creators: name: Arregui, Inigo
name: Ballester, Jose Luis
name: Goossens, Marcel
Publisher: name: arXiv
Year: 2008
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: There is not as yet full agreement on the mechanism that causes the rapid damping of the oscillations observed by TRACE in coronal loops. It has been suggested that the variation of the observed values of the damping time as function of the corresponding observed values of the period contains information on the possible damping mechanism. The aim of this Letter is to show that, for resonant absorption, this is definitely not the case unless detailed a priori information on the individual loops is available.
Determinants of flour dust exposure in bakeries
Creators: name: Burstyn, Igor
Publisher: name: University of British Columbia
Year: 2009

description: This thesis presents the results of an investigation into factors that are associated with flour dust exposures in B.C. bakeries. We describe observed exposure levels and advise on control measures which may reduce an individual's exposure to flour dust. In this investigation, flour dust exposure was assesed using three measures: inhalable dust, wheat antigen and fungal a-amylase. Inhalable dust was measured gravimetrically. The wheat antigen and a-amylase content of the water soluble fraction of inhalable dust was assayed via ELISA. Ninety-six bakery workers, employed in seven different bakeries, participated in the investigation. Two side-by-side full-shift inhalable dust samples were obtained from each study participant on a single occasion. We were able to obtain useable exposure measurements for all three exposure measures from each study participant. During sampling, information on potential determinants of exposure was collected. It was used in analysis of variance and multiple regression to identify significant predictors of exposure (determinants). The exposure levels observed in this study indicated that the bakery workers were subject to a mean inhalable dust exposure of 8.2 mg/m3 (ranging from 0.1 to 110 mg/m3), a mean a-amylase exposure of 22.0 ng/m3 (ranging from below limit of detection of 0.1 to 307.1 ng/m3) and a mean wheat antigen exposure of 109 ug/m3 (ranging from below limit of detection of 1 to 1018 ug/m3). Seventeen percent of the measured inhalable dust exposures exceeded the regulatory exposure limit of 10 mg/m3. Some wheat antigen and a-amylase exposures showed levels capable of causing respiratory symptoms. Regression, models which explained 74 to 79% of variability in inhalable dust, a-amylase and wheat antigen exposures were constructed. According to the models, tasks such as weighing, pouring and operating dough forming machinery increased flour dust exposure, while fully automated forming, packing, catching and decorating decreased exposure. Bread, bun and puff pastry production lines were associated with increased exposure, while cake production was associated with decreased exposures. We describe a novel method of controlling the exposures in bakeries via the substitution of dusting with the use of the divider oil, and discuss which pieces of equipment appear to be associated with elevated exposures.
Thermodynamics of the one-dimensional half-filled Hubbard model in the spin-disordered regime
Creators: name: Ejima, S.
name: Essler, F. H. L.
name: Gebhard, F.
Publisher: name: arXiv
Year: 2006
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: We analyze the Thermodynamic Bethe Ansatz equations of the one-dimensional half-filled Hubbard model in the "spin-disordered regime", which is characterized by the temperature being much larger than the magnetic energy scale but small compared to the Mott-Hubbard gap. In this regime the thermodynamics of the Hubbard model can be thought of in terms of gapped charged excitations with an effective dispersion and spin degrees of freedom that only contribute entropically. In particular, the internal energy and the effective dispersion become essentially independent of temperature. An interpretation of this regime in terms of a putative interacting-electron system at zero temperature leads to a metal-insulator transition at a finite interaction strength above which the gap opens linearly. We relate these observations to studies of the Mott-Hubbard transition in the limit of infinite dimensions.
description: 15 pages, 3 figures
Local embedding of Coupled Cluster theory into the Random Phase Approximation using plane-waves
Creators: name: Schäfer, Tobias
name: Libisch, Florian
name: Kresse, Georg
name: Grüneis, Andreas
Publisher: name: arXiv
Year: 2020
Subjects: subject: Chemical Physics (physics.chem-ph)
subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: We present an embedding approach to treat local electron correlation effects in periodic environments. In a single, consistent framework, our plane-wave based scheme embeds a local high-level correlation calculation (here Coupled Cluster Theory, CC), employing localized orbitals, into a low-level correlation calculation (here the direct Random Phase Approximation, RPA). This choice allows for an accurate and effcient treatment of long-range dispersion effects. Accelerated convergence with respect to the local fragment size can be observed if the low-level and high-level long-range dispersion are quantitatively similar, as is the case for CC in RPA. To demonstrate the capabilities of the introduced embedding approach, we calculate adsorption energies of molecules on a surface and in a chabazite crystal cage, as well as the formation energy of a lattice impurity in a solid at the level of highly accurate many-electron perturbation theories. The absorption energy of a methane molecule in a zeolite chabazite, for instance, is converged with an error well below 20 meV at the CC level. As our largest periodic benchmark system, we apply our scheme to the adsorption of a water molecule on titania in a supercell containing more than 1000 electrons.
description: 6 pages, 2 figures
Discontinuous Galerkin methods for a dispersive wave hydro-sediment-morphodynamic model
Creators: name: Kazhyken, Kazbek
name: Videman, Juha
name: Dawson, Clint
Publisher: name: arXiv
Year: 2020
Subjects: subject: Numerical Analysis (math.NA)
subject: FOS: Mathematics

description: A dispersive wave hydro-sediment-morphodynamic model developed by complementing the shallow water hydro-sediment-morphodynamic (SHSM) equations with the dispersive term from the Green-Naghdi equations is presented. A numerical solution algorithm for the model based on the second-order Strang operator splitting is presented. The model is partitioned into two parts, (1) the SHSM equations and (2) the dispersive correction part, which are discretized using discontinuous Galerkin finite element methods. This splitting technique provides a facility to select dynamically regions of a problem domain where the dispersive term is not applied, e.g. wave breaking regions where the dispersive wave model is no longer valid. Algorithms that can handle wetting-drying and detect wave breaking are provided and a number of numerical examples are presented to validate the developed numerical solution algorithm. The results of the simulations indicate that the model is capable of predicting sediment transport and bed morphodynamic processes correctly provided that the empirical models for the suspended and bed load transport are properly calibrated. Moreover, the developed model is able to accurately capture hydrodynamics and wave dispersion effects up to swash zones, and its application is justified for simulations where dispersive wave effects are prevalent.
description: arXiv admin note: text overlap with arXiv:2005.00920
Resonant inelastic x-ray scattering spectra in the hyperhoneycomb iridate $β$-Li$_2$IrO$_3$: First principles calculations
Creators: name: Antonov, V. N.
name: Kukusta, D. A.
name: Uba, L.
name: Bonda, A.
name: Uba, S.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: We studied the electronic structure of $β$-Li$_2$IrO$_3$ insulator within the density-functional theory using the generalized gradient approximation with taking into account strong Coulomb correlations in the framework of the fully relativistic spin-polarized Dirac linear muffin-tin orbital band-structure method. The $β$-Li$_2$IrO$_3$ undergoes a pressure-induced structural and magnetic phase transitions at $P_c$ $\sim$4 GPa with symmetry lowering to the monoclinic $C2/c$. The structural phase transition is accompanied by the formation of Ir$_2$ dimers on the zigzag chains, with an Ir-Ir distance of $\sim$2.66~Å, even shorter than that of metallic Ir. The strong dimerization stabilizes the bonding molecular-orbital state, leads to the collapse of the magnetism and opens the energy gap with a concomitant electronic phase transition from a Mott insulator to band insulator. The resonant inelastic x-ray scattering spectra (RIXS) at the Ir $L_3$ edge were investigated theoretically from first principles. The calculated results are in good agreement with the experimental data. We show that the the drastic reconstruction of the RIXS spectral peak at 0.7 eV associated with the structural $Fddd \rightarrow C2/c$ phase transition at $P_c$ can be related to disappearing of the Coulomb correlations in the high-pressure $C2/c$ phase
DigComp ở nơi làm việc: Khung năng lực số của Liên minh châu Âu trong hành động trong thị trường lao động: lựa chọn các trường hợp điển hình
Creators: name: Nghĩa, Lê Trung
Publisher: name: Zenodo
Year: 2024

description: Đây là bản dịch tài liệu: Kluzer S., Centeno C. and O ́Keeffe, W., DigComp ở nơi làm việc, EUR 30166 EN, Văn phòng Xuất bản của Liên minh châu Âu, Luxembourg, 2020, ISBN 978-92-76-22558-4, doi:10.2760/17763, JRC120376. Bản gốc tiếng Anh có tại địa chỉ: https://publications.jrc.ec.europa.eu/repository/bitstream/JRC120376/digcomp_at_work_090720_1.pdf
Perceptions of the helpfulness of a home follow up program to post myocardial infarction patients
Creators: name: Gleason, Patricia Gail
Publisher: name: University of British Columbia
Year: 2009

description: The purpose of this study was to describe the elements of a hospital funded, community based cardiac home follow up program which post myocardial patients and families found helpful during the recovery period immediately after discharge from hospital to six weeks post discharge. A retrospective descriptive survey was conducted on a convenience sample of 96 program participants. Forty eight participants returned the Cardiac Home Follow Up Questionnaire. The responses and scores of the items on the questionnaire were analyzed with descriptive statistics. The patients in this sample found the elements of information about physical changes, individualized recovery plan, and the supervised, graduated exercise components of the program to be helpful to them in their recovery during the first 6 weeks after discharge from hospital. While patients and families found that the weekly home visits from the nurse were supportive, they also identified a need for more assistance in strategies to deal with emotional aspects of heart disease. The issue of family involvement in the home follow up program also yielded some interesting data. While most of the participants agreed that the experience of a myocardial infarction influenced family functioning and therefore, family involvement was a positive intervention for their recovery, 27% of the sample opposed this idea. Despite discrepancies in the family involvement content area, a majority of participants acknowledged that the home follow up program assisted them in maintaining lifestyle changes made after their myocardial infarction. Finally, most participants and family members were very satisfied with the program and many viewed the experience as part of the comprehensive cardiac care provided by their community hospital. The findings are discussed in relation to the literature on patient education and research on individualized cardiac follow up programs. The implications for nursing practice, education, and research are outlined.
The Future is Big Graphs! A Community View on Graph Processing Systems
Creators: name: Sakr, Sherif
name: Bonifati, Angela
name: Voigt, Hannes
name: Iosup, Alexandru
name: Ammar, Khaled
name: Angles, Renzo
name: Aref, Walid
name: Arenas, Marcelo
name: Besta, Maciej
name: Boncz, Peter A.
name: Daudjee, Khuzaima
name: Della Valle, Emanuele
name: Dumbrava, Stefania
name: Hartig, Olaf
name: Haslhofer, Bernhard
name: Hegeman, Tim
name: Hidders, Jan
name: Hose, Katja
name: Iamnitchi, Adriana
name: Kalavri, Vasiliki
name: Kapp, Hugo
name: Martens, Wim
name: Özsu, M. Tamer
name: Peukert, Eric
name: Plantikow, Stefan
name: Ragab, Mohamed
name: Ripeanu, Matei R.
name: Salihoglu, Semih
name: Schulz, Christian
name: Selmer, Petra
name: Sequeda, Juan F.
name: Shinavier, Joshua
name: Szárnyas, Gábor
name: Tommasini, Riccardo
name: Tumeo, Antonino
name: Uta, Alexandru
name: Varbanescu, Ana Lucia
name: Wu, Hsiang-Yun
name: Yakovets, Nikolay
name: Yan, Da
name: Yoneki, Eiko
Publisher: name: arXiv
Year: 2020
Subjects: subject: Distributed, Parallel, and Cluster Computing (cs.DC)
subject: Databases (cs.DB)
subject: FOS: Computer and information sciences
subject: C.3; E.0; H.2; J.0

description: Graphs are by nature unifying abstractions that can leverage interconnectedness to represent, explore, predict, and explain real- and digital-world phenomena. Although real users and consumers of graph instances and graph workloads understand these abstractions, future problems will require new abstractions and systems. What needs to happen in the next decade for big graph processing to continue to succeed?
description: 12 pages, 3 figures, collaboration between the large-scale systems and data management communities, work started at the Dagstuhl Seminar 19491 on Big Graph Processing Systems, to be published in the Communications of the ACM
Sums of Powers and Majorization
Creators: name: Gao, Peng
Publisher: name: arXiv
Year: 2007
Subjects: subject: Classical Analysis and ODEs (math.CA)
subject: FOS: Mathematics
subject: 26D15

description: We study certain sequences involving sums of powers of positive integers and in connection with this, we give examples to show that power majorization does not imply majorization.
Accuracy, Stability, and Performance Comparison between the Spectral Difference and Flux Reconstruction Schemes
Creators: name: Cox, Christopher
name: Trojak, Will
name: Dzanic, Tarik
name: Witherden, Freddie
name: Jameson, Antony
Publisher: name: arXiv
Year: 2020
Subjects: subject: Computational Physics (physics.comp-ph)
subject: Fluid Dynamics (physics.flu-dyn)
subject: FOS: Physical sciences

description: We report the development of a discontinuous spectral element flow solver that includes the implementation of both spectral difference and flux reconstruction formulations. With this high order framework, we have constructed a foundation upon which to provide a fair and accurate assessment of these two schemes in terms of accuracy, stability, and performance with special attention to the true spectral difference scheme and the modified spectral difference scheme recovered via the flux reconstruction formulation. Building on previous analysis of the spectral difference and flux reconstruction schemes, we provide a novel nonlinear stability analysis of the spectral difference scheme. Through various numerical experiments, we demonstrate the additional stability afforded by the true, baseline spectral difference scheme without explicit filtering or de-aliasing due to its inherent feature of staggered flux points. This arrangement leads to favorable suppression of aliasing errors and improves stability needed for under-resolved simulations of turbulent flows.
description: 44 pages, 15 figures, 3 tables
Central Stellar Populations of S0 Galaxies in The Fornax Cluster
Creators: name: Bedregal, A. G.
name: Aragón-Salamanca, A.
name: Merrifield, M. R.
name: Cardiel, N.
Publisher: name: arXiv
Year: 2007
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: Based on FORS2-VLT long-slit spectroscopy, the analysis of the central absorption line indices of 9 S0 galaxies in the Fornax Cluster is presented. Central indices correlate with central velocity dispersions as observed in ellipticals. However, the stellar population properties of these S0s indicates that the observed trends are produced by relative differences in age and alpha-element abundances and not in metallicity ([Fe/H]) as previous studies have found in elliptical galaxies. The observed scatter in the line indices vs. velocity dispersion relations can be partially explained by the rotationally-supported nature of many of these systems. The presence of tighter line indices vs. maximum (circular) rotational velocity relations confirms this statement. It was also confirmed that the dynamical mass is the driving physical property of all these correlations and in our Fornax S0s it has to be estimated assuming rotational support.
description: To appear in the Proceedings of IAU Symposium 241: "Stellar Populations as Building Blocks of Galaxies", 10-16 December, 2006 at La Palma, Canary Islands, Spain
The impact of dark matter decays and annihilations on the formation of the first structures
Creators: name: Ripamonti, E.
name: Mapelli, M.
name: Ferrara, A.
Publisher: name: arXiv
Year: 2006
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: We derive the effects of DM decays and annihilations on structure formation. We consider moderately massive DM particles (sterile neutrinos and light DM), as they are expected to give the maximum contribution to heating and reionization. The energy injection from DM decays and annihilations produces both an enhancement in the abundance of coolants (H2 and HD) and an increase of gas temperature. We find that for all the considered DM models the critical halo mass for collapse, m_crit, is generally higher than in the unperturbed case. However, the variation of m_crit is small. In the most extreme case, i.e. considering light DM annihilations (decays) and halos virializing at redshift z_vir>10 (z_vir~10), m_crit increases by a factor ~4 (~2). In the case of annihilations the variations of m_crit are also sensitive to the assumed profile of the DM halo. Furthermore, we note that the fraction of gas which is retained inside the halo is substantially reduced (to ~40 per cent of the cosmic value), especially in the smallest halos, as a consequence of the energy injection by DM decays and annihilations.
description: 11 pages, 8 figures; revised version accepted for publication in MNRAS
Magnetodielectric coupling in a triangular Ising lattice
Creators: name: Bellido, Natalia
name: Simon, Charles
name: Maignan, Antoine
Publisher: name: arXiv
Year: 2008
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: Dielectric constant measurement under magnetic field is an efficient technique to study the coupling between charges and spins in insulating materials. For magnetic oxides, the geometric frustration is known to be a key ingredient to observe such a coupling. Measurements for the triangular Ising-like cobaltite Ca3Co2O6 have been made. Single crystals of Ca3Co2O6 are found to exhibit a magnetodielectric effect below TN=25K with a peak in the e(H) curve at the ferri to ferromagnetic transition. This relation between e and magnetization has been modelized by using two order parameters in an energy expansion derived from the Landau formalism and the fluctuation-dissipation theorem. This result emphasizes the great potential of insulating transition metal oxides for the search of magnetodielectric effect.
Recoil Velocities from Equal-Mass Binary-Black-Hole Mergers
Creators: name: Koppitz, Michael
name: Pollney, Denis
name: Reisswig, Christian
name: Rezzolla, Luciano
name: Thornburg, Jonathan
name: Diener, Peter
name: Schnetter, Erik
Publisher: name: arXiv
Year: 2007
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: The final evolution of a binary black-hole system gives rise to a recoil velocity if an asymmetry is present in the emitted gravitational radiation. Measurements of this effect for non-spinning binaries with unequal masses have pointed out that kick velocities $\sim~175$ km/s can be reached for a mass ratio $\simeq 0.36$. However, a larger recoil can be obtained for equal-mass binaries if the asymmetry is provided by the spins. Using two independent methods we show that the merger of such binaries yields velocities as large as $\sim 440$ km/s for black holes having unequal spins that are antialigned and parallel to the orbital angular momentum.
description: 4 pages, 3 color eps figures
Relative cohomology of polynomial mappings
Creators: name: Bonnet, Philippe
Publisher: name: arXiv
Year: 2006
Subjects: subject: Algebraic Geometry (math.AG)
subject: Commutative Algebra (math.AC)
subject: FOS: Mathematics
subject: 14F10; 14F40; 14R99

description: Let $F$ be a polynomial mappping from $\mathbb{C}^n$ to $\mathbb{C}^q$ with $n>q$. We study the De Rham cohomology of its fibres and its relative cohomology groups, by introducing a special fibre $F^{-1}(\infty)$ "at infinity" and its cohomology. Let us fix a weighted homogeneous degree on $\mathbb{C}[x_1,...,x_n]$ with strictly positive weights. The fibre at infinity is the zero set of the leading terms of the coordinate functions of $F$. We introduce the cohomology groups $H^k(F^{-1}(\infty))$ of $F$ at infinity. These groups enable us to compute all the other cohomology groups of $F$. For instance, if the fibre at infinity has an isolated singularity at the origin, we prove that every weighted homogeneous basis of $H^{n-q}(F^{-1}(\infty))$ is a basis of all the groups $H^{n-q}(F^{-1}(y))$ and also a basis a the $(n-q)^{th}$ relative cohomology group of $F$. Moreover the dimension of $H^{n-q}(F^{-1}(\infty))$ is given by a global Milnor number of $F$, which only depends on the leading terms of the coordinate functions of $F$.
description: 20 pages
Optical and electrical spin injection and spin transport in hybrid Fe/GaAs devices
Creators: name: Crooker, S. A.
name: Furis, M.
name: Lou, X.
name: Smith, D. L.
name: Adelmann, C.
name: Palmstrom, C. J.
name: Crowell, P. A.
Publisher: name: arXiv
Year: 2006
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: We discuss methods for imaging the nonequilibrium spin polarization of electrons in Fe/GaAs spin transport devices. Both optically- and electrically-injected spin distributions are studied by scanning magneto-optical Kerr rotation microscopy. Related methods are used to demonstrate electrical spin detection of optically-injected spin polarized currents. Dynamical properties of spin transport are inferred from studies based on the Hanle effect, and the influence of strain on spin transport data in these devices is discussed.
description: 5 pages, 6 figs. ICPS-28 proceedings (July'06, Vienna) for J. Appl. Phys
Pixelated 3D sensors for tracking in radiation harsh environments
Creators: name: Duarte-Campderros, Jordi
Publisher: name: arXiv
Year: 2021
Subjects: subject: Instrumentation and Detectors (physics.ins-det)
subject: FOS: Physical sciences

description: The High Luminosity upgrade of the CERN Large Hadron Collider will be able to reach a peak instantaneous luminosity of 5E34/cm2 s. The innermost detectors of the CMS and ATLAS experiments will have to cope with unprecedented requirements on radiation hardness. At the end of the operation period, radiation levels are expected to reach values above 2.6E16 neq/cm2. Sensors based on 3D pixel technology, with intrinsic radiation tolerance, are the baseline option for the innermost layers of the vertex detectors of several HL-LHC experiments. This article gives an overview of the ongoing characterization of the pixelated 3D sensor technology, their performance and their current development status for tracking on radiation harsh environments.
description: Proceedings of the The 29th International Workshop on Vertex Detectors (VERTEX2020)
Investigation of the Tunneling Spectra in HgBr2-Intercalated Bi-2212 Single Crystals below and above Tc
Creators: name: Kurter, C.
name: Mazur, D.
name: Ozyuzer, L.
name: Hinks, D. G.
name: Gray, K. E.
Publisher: name: arXiv
Year: 2007
Subjects: subject: Superconductivity (cond-mat.supr-con)
subject: FOS: Physical sciences

description: Interlayer tunneling spectroscopy measurements were performed on mesa arrays of Bi-2212 single crystals, intercalated with HgBr$_2$. Tunneling conductances were obtained over a wide temperature range to examine the spectral features, especially the behavior of the quasiparticle peaks corresponding to superconducting energy gaps (SGs). Experimental spectra showed that gap-like features are still present even for the temperatures far above the transition temperature, T$_c$. This evidence is consistent with the idea that the SG evolves into a pseudogap above T$_c$ for HgBr$_2$-intercalated Bi-2212 single crystals.
description: M2S-HTSC-VII Conference Proceedings, 2 pages, 2 figures
การออกแบบสถานีวัดอากาศขนาดเล็กราคาประหยัดโดยใช้โปรแกรม LabVIEW
Creators: name: นภัทร  วัจนเทพินทร์
name: ไชยยันต์  บุญมี
Publisher: name: มหาวิทยาลัยเทคโนโลยีราชมงคลสุวรรณภูมิ
Year: 2015
Subjects: Micro-climate Station, Climate monitor software, temperature, relative humidity, Solar Irradiance, LabVIEW

description: 2, 9, วารสารวิชาการและวิจัย มทร.พระนคร
ประสิทธิภาพของสาหร่ายหางกระรอกในการปรับปรุงคุณภาพน้ำ
Creators: name: กิตติมา  วานิชกูล
name: สมิง จำปาศรี
name: จิราพร  กุลคำ
name: พิรุณ  จันทร์เทวี
name: ยุพาวรรณ  ประเสริฐโชค
Publisher: name: มหาวิทยาลัยเทคโนโลยีราชมงคลธัญบุรี
Year: 2015
Subjects: Hydrilla, water treatment, water quality

description: 2, 9, วารสารวิชาการและวิจัย มทร.พระนคร
Some challenges for Nuclear Density Functional Theory
Creators: name: Duguet, T.
name: Bennaceur, K.
name: Lesinski, T.
name: Meyer, J.
Publisher: name: arXiv
Year: 2006
Subjects: subject: Nuclear Theory (nucl-th)
subject: FOS: Physical sciences

description: We discuss some of the challenges that the DFT community faces in its quest for the truly universal energy density functional applicable over the entire nuclear chart.
description: 12 pages, 3 figures, invited talk at the 3rd ANL/MSU/INT/JINA RIA Theory workshop, April 4th - 7th, 2006, Argonne National Laboratory, USA. Proceeding to be published in World Scientific
EVR-CB-004: An Inflated Hot Subdwarf O star + Unseen WD Companion in a Compact Binary Discovered with the Evryscope
Creators: name: Ratzloff, Jeffrey K.
name: Kupfer, Thomas
name: Barlow, Brad N.
name: Schneider, David
name: Marsh, Thomas R.
name: Heber, Ulrich
name: Corcoran, Kyle A.
name: Bauer, Evan
name: Hammerich, Steven
name: Corbett, Henry T.
name: Glazier, Amy
name: Howard, Ward S.
name: Law, Nicholas M.
Publisher: name: arXiv
Year: 2020
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: We present the discovery of EVR-CB-004, a close binary with a remnant stellar core and an unseen white dwarf companion. The analysis in this work reveals the primary is potentially an inflated hot subdwarf (sdO) and more likely is a rarer post-blue horizontal branch (post-BHB) star. Post-BHBs are the short-lived shell-burning final stage of a blue horizontal star or hot subdwarf before transitioning to a WD. This object was discovered using Evryscope photometric data in a southern-all-sky hot subdwarf variability survey. The photometric light curve for EVR-CB-004 shows multi-component variability from ellipsoidal deformation of the primary and from Doppler boosting as well as gravitational limb darkening. EVR-CB-004 is one of just a handful of known systems, and has a long period (6.08426 hours) and large amplitude ellipsoidal modulation (16.0 $\%$ change in brightness from maximum to minimum) for these extremely close binary systems, while the properties of the primary make it a truly unique system. EVR-CB-004 also shows a peculiar low-amplitude (less than $1\%$) sinusoidal light curve variation with a period that is a 1/3 resonance of the binary period. We tentatively identify this additional variation source as a tidally-induced resonant pulsation, and we suggest followup observations that could verify this interpretation. From the evolutionary state of the system, its components, and its mass fraction, EVR-CB-004 is a strong merger candidate to form a single high-mass ($\approx1.2M_{\odot}$) WD. EVR-CB-004 offers a glimpse into a brief phase of a remnant core evolution and secondary variation, not seen before in a compact binary.
description: Accepted to ApJ September 7, 2020
Non-gaussianity from the trispectrum in general single field inflation
Creators: name: Arroja, Frederico
name: Koyama, Kazuya
Publisher: name: arXiv
Year: 2008
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: Astrophysics (astro-ph)
subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: We compute the fourth order action in perturbation theory for scalar and second order tensor perturbations for a minimally coupled single field inflationary model, where the inflaton's lagrangian is a general function of the field's value and its kinetic energy. We obtain the fourth order action in two gauges, the comoving gauge and the uniform curvature gauge. Using the comoving gauge action we calculate the trispectrum at leading order in slow-roll, finding agreement with a previously known result in the literature. We point out that in general to obtain the correct leading order trispectrum one cannot ignore second order tensor perturbations as previously done by others. The next-to-leading order corrections may become detectable depending on the shape and we provide the necessary formalism to calculate them.
description: v2: reference added, typos corrected, replaced to match published version v3: arguments on the full 4th order interaction hamiltonian corrected
Qualité des services éducationnels dans un établissement supérieur d’enseignement à distance basé sur les TIC : perception des étudiants
Creators: name: Dieng, Amy
name: Ba, Serigne Ababacar Cissé
name: Sané, Mamadou Vieux Lamine
name: RICS, Revue
Publisher: name: figshare
Year: 2021
Subjects: Education

description: La qualité de l’enseignement supérieur est devenue essentielle pour le progrès d’un pays. Pour répondre aux besoins croissants de prise en charge des étudiants au Sénégal, l’UVS a été mise sur pied en 2013, avec la particularité de proposer un enseignement à distance basé sur les TIC. Ainsi, mesurer la perception de la qualité des services éducationnels de l’UVS, fonde ce travail de recherche. La méthodologie est basée sur une démarche hypothético-déductive selon une approche quantitative. Le modèle SERVQUAL de Mahjoubi (2001) a été utilisé. Après recensement, la population d’étude constitue 74,2% des étudiants inscrits au programme de Master en sciences de l’éducation. Les résultats obtenus ont permis de caractériser le profil d’apprentissage des étudiants.
Non-uniform Motion Deblurring with Blurry Component Divided Guidance
Creators: name: Wang, Pei
name: Sun, Wei
name: Yan, Qingsen
name: Niu, Axi
name: Li, Rui
name: Zhu, Yu
name: Sun, Jinqiu
name: Zhang, Yanning
Publisher: name: arXiv
Year: 2021
Subjects: subject: Computer Vision and Pattern Recognition (cs.CV)
subject: FOS: Computer and information sciences

description: Blind image deblurring is a fundamental and challenging computer vision problem, which aims to recover both the blur kernel and the latent sharp image from only a blurry observation. Despite the superiority of deep learning methods in image deblurring have displayed, there still exists major challenge with various non-uniform motion blur. Previous methods simply take all the image features as the input to the decoder, which handles different degrees (e.g. large blur, small blur) simultaneously, leading to challenges for sharp image generation. To tackle the above problems, we present a deep two-branch network to deal with blurry images via a component divided module, which divides an image into two components based on the representation of blurry degree. Specifically, two component attentive blocks are employed to learn attention maps to exploit useful deblurring feature representations on both large and small blurry regions. Then, the blur-aware features are fed into two-branch reconstruction decoders respectively. In addition, a new feature fusion mechanism, orientation-based feature fusion, is proposed to merge sharp features of the two branches. Both qualitative and quantitative experimental results show that our method performs favorably against the state-of-the-art approaches.
Strange Quark Contribution to the Proton Spin, from Elastic $\vec{e}p$ and $νp$ Scattering
Creators: name: Pate, Stephen
Publisher: name: arXiv
Year: 2006
Subjects: subject: High Energy Physics - Experiment (hep-ex)
subject: Nuclear Experiment (nucl-ex)
subject: FOS: Physical sciences

description: The strangeness contribution to the vector and axial form factors of the proton is presented for momentum transfers in the range 0.45 < $Q^2$ < 1.0 GeV$^2$. The results are obtained via a combined analysis of forward-scattering parity-violating elastic $\vec{e}p$ asymmetry data from the G0 and HAPPEx experiments at Jefferson Lab, and elastic $νp$ and $\barνp$ scattering data from Experiment 734 at Brookhaven National Laboratory. The combination of the two data sets allows for the simultaneous extraction of $G_E^s$, $G_M^s$, and $G_A^s$ over a significant range of $Q^2$ for the very first time. Determination of the strange axial form factor $G_A^s$ is vital to an understanding of the strange quark contribution to the proton spin.
description: 4 pages, 1 figure; proceedings for SPIN 2006; will be published in AIP Conference Proceedings
Semi-classical stability of AdS NUT instantons
Creators: name: Warnick, Claude
Publisher: name: arXiv
Year: 2006
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: The semi-classical stability of several AdS NUT instantons is studied. Throughout, the notion of stability is that of stability at the one-loop level of Euclidean Quantum Gravity. Instabilities manifest themselves as negative eigenmodes of a modified Lichnerowicz Laplacian acting on the transverse traceless perturbations. An instability is found for one branch of the AdS-Taub-Bolt family of metrics and it is argued that the other branch is stable. It is also argued that the AdS-Taub-NUT family of metrics are stable. A component of the continuous spectrum of the modified Lichnerowicz operator on all three families of metrics is found.
description: 18 pages, 3 figures; references added
Proximity Tracing in an Ecosystem of Surveillance Capitalism
Creators: name: Dehaye, Paul-Olivier
name: Reardon, Joel
Publisher: name: arXiv
Year: 2020
Subjects: subject: Cryptography and Security (cs.CR)
subject: FOS: Computer and information sciences

description: Proximity tracing apps have been proposed as an aide in dealing with the COVID-19 crisis. Some of those apps leverage attenuation of Bluetooth beacons from mobile devices to build a record of proximate encounters between a pair of device owners. The underlying protocols are known to suffer from false positive and re-identification attacks. We present evidence that the attacker's difficulty in mounting such attacks has been overestimated. Indeed, an attacker leveraging a moderately successful app or SDK with Bluetooth and location access can eavesdrop and interfere with these proximity tracing systems at no hardware cost and perform these attacks against users who do not have this app or SDK installed. We describe concrete examples of actors who would be in a good position to execute such attacks. We further present a novel attack, which we call a biosurveillance attack, which allows the attacker to monitor the exposure risk of a smartphone user who installs their app or SDK but who does not use any contact tracing system and may falsely believe that they have opted out of the system. Through traffic auditing with an instrumented testbed, we characterize precisely the behaviour of one such SDK that we found in a handful of apps---but installed on more than one hundred million mobile devices. Its behaviour is functionally indistinguishable from a re-identification or biosurveillance attack and capable of executing a false positive attack with minimal effort. We also discuss how easily an attacker could acquire a position conducive to such attacks, by leveraging the lax logic for granting permissions to apps in the Android framework: any app with some geolocation permission could acquire the necessary Bluetooth permission through an upgrade, without any additional user prompt. Finally we discuss motives for conducting such attacks.
Preprocessing of vector magnetograms for magnetohydrostatic extrapolations
Creators: name: Zhu, Xiaoshuai
name: Wiegelmann, Thomas
name: Inhester, Bernd
Publisher: name: arXiv
Year: 2020
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: Context. Understanding the 3D magnetic field as well as the plasma in the chromosphere and transition region is important. One way is to extrapolate the magnetic field and plasma from the routinely measured vector magnetogram on the photosphere based on the assumption of the magnetohydrostatic (MHS) state. However, photospheric data may be inconsistent with the MHS assumption. Therefore, we must study the restriction on the photospheric magnetic field, which is required by the MHS system. Moreover, the data should be transformed accordingly before MHS extrapolations can be applied. Aims. We aim to obtain a set of surface integrals as criteria for the MHS system and use this set of integrals to preprocess a vector magnetogram. Methods. By applying Gauss' theorem and assuming an isolated active region on the Sun, we related the magnetic energy and forces in the volume to the surface integral on the photosphere. The same method was applied to obtain restrictions on the photospheric magnetic field as necessary criteria for a MHS system. We used an optimization method to preprocess the data to minimize the deviation from the criteria as well as the measured value. Results. By applying the virial theorem to the active region, we find the boundary integral that is used to compute the energy of a force-free field usually underestimates the magnetic energy of a large active region. We also find that the MHS assumption only requires the x-, y-component of net Lorentz force and the z-component of net torque to be zero. These zero components are part of Aly's criteria for a force-free field. However, other components of net force and torque can be non-zero values. According to new criteria, we preprocess the magnetogram to make it more consistent with the MHS system and, at the same time close, to the original data.
description: Accepted by A&A