1,425 research outputs found

    Beyond traditional wind farm noise characterisation using transfer learning

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    Published Online: 10 May 2022This study proposes an approach for the characterisation and assessment of wind farm noise (WFN), which is based on extraction of acoustic features between 125 and 7500 Hz from a pretrained deep learning model (referred to as deep acoustic features). Using data measured at a variety of locations, this study shows that deep acoustic features can be linked to meaningful characteristics of the noise. This study finds that deep acoustic features can reveal an improved spatial and temporal representation of WFN compared to what is revealed using traditional spectral analysis and overall noise descriptors. These results showed that this approach is promising, and thus it could provide the basis for an improved framework for WFN assessment in the future.Phuc D. Nguyen, Kristy L. Hansen, Bastien Lechat, Branko Zajamsek, Colin Hansen, and Peter Catchesid

    Can residuals of the Solar system foreground explain low multipole anomalies of the CMB ?

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    The low multipole anomalies of the Cosmic Microwave Background has received much attention during the last few years. It is still not ascertained whether these anomalies are indeed primordial or the result of systematics or foregrounds. An example of a foreground, which could generate some non-Gaussian and statistically anisotropic features at low multipole range, is the very symmetric Kuiper Belt in the outer solar system. In this paper, expanding upon the methods presented by Maris et al. (2011), we investigate the contributions from the Kuiper Belt objects (KBO) to the WMAP ILC 7 map, whereby we can minimize the contrast in power between even and odd multipoles in the CMB, discussed discussed by Kim & Naselsky (2010). We submit our KBO de-correlated CMB signal to several tests, to analyze its validity, and find that incorporation of the KBO emission can decrease the quadrupole-octupole alignment and parity asymmetry problems, provided that the KBO signals has a non-cosmological dipole modulation, associated with the statistical anisotropy of the ILC 7 map. Additionally, we show that the amplitude of the dipole modulation, within a 2 sigma interval, is in agreement with the corresponding amplitudes, discussed by Lew (2008).Comment: 24 pages, 9 figures, 5 tables. Matches version in JCA

    Lines, Circles, Planes and Spheres

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    Let SS be a set of nn points in R3\mathbb{R}^3, no three collinear and not all coplanar. If at most nkn-k are coplanar and nn is sufficiently large, the total number of planes determined is at least 1+k(nk2)(k2)(nk2)1 + k \binom{n-k}{2}-\binom{k}{2}(\frac{n-k}{2}). For similar conditions and sufficiently large nn, (inspired by the work of P. D. T. A. Elliott in \cite{Ell67}) we also show that the number of spheres determined by nn points is at least 1+(n13)t3orchard(n1)1+\binom{n-1}{3}-t_3^{orchard}(n-1), and this bound is best possible under its hypothesis. (By t3orchard(n)t_3^{orchard}(n), we are denoting the maximum number of three-point lines attainable by a configuration of nn points, no four collinear, in the plane, i.e., the classic Orchard Problem.) New lower bounds are also given for both lines and circles.Comment: 37 page

    Antimatter from the cosmological baryogenesis and the anisotropies and polarization of the CMB radiation

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    We discuss the hypotheses that cosmological baryon asymmetry and entropy were produced in the early Universe by phase transition of the scalar fields in the framework of spontaneous baryogenesis scenario. We show that annihilation of the matter-antimatter clouds during the cosmological hydrogen recombination could distort of the CMB anisotropies and polarization by delay of the recombination. After recombination the annihilation of the antibaryonic clouds (ABC) and baryonic matter can produce peak-like reionization at the high redshifts before formation of quasars and early galaxy formation. We discuss the constraints on the parameters of spontaneous baryogenesis scenario by the recent WMAP CMB anisotropy and polarization data and on possible manifestation of the antimatter clouds in the upcoming PLANCK data.Comment: PRD in press with minor change

    Emergency Medical Services (EMS) Activities Funded by the Medicare Rural Hospital Flexibility Program

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    Since the first full year of Flex Program funding, the number and range of EMS improvement activities proposed by participating facilities has increased substantially. This report describes the EMS-related projects that states proposed to conduct in fiscal year 2004-2005

    PArthENoPE: Public Algorithm Evaluating the Nucleosynthesis of Primordial Elements

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    We describe a program for computing the abundances of light elements produced during Big Bang Nucleosynthesis which is publicly available at http://parthenope.na.infn.it/. Starting from nuclear statistical equilibrium conditions the program solves the set of coupled ordinary differential equations, follows the departure from chemical equilibrium of nuclear species, and determines their asymptotic abundances as function of several input cosmological parameters as the baryon density, the number of effective neutrino, the value of cosmological constant and the neutrino chemical potential. The program requires commercial NAG library routines.Comment: 18 pages, 2 figures. Version accepted by Comp. Phys. Com. The code (and an updated manual) is publicly available at http://parthenope.na.infn.it

    Исследование температурного поля пневматического молотка

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    Представлены результаты экспериментального исследования изменения температуры поверхности рубильного пневматического молотка М-6 по времени при рубке в различных режимах стальной полосы и плиты, чугунной плиты

    Near-threshold measurement of the 4He(g,n) reaction

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    A near-threshold 4He(g,n) cross-section measurement has been performed at MAX-lab. Tagged photons from 23 < Eg < 42 MeV were directed toward a liquid 4He target, and neutrons were detected by time-of-flight in two liquid-scintillator arrays. Seven-point angular distributions were measured for eight photon energies. The results are compared to experimental data measured at comparable energies and Recoil-Corrected Continuum Shell Model, Resonating Group Method, and recent Hyperspherical-Harmonic Expansion calculations. The angle-integrated cross-section data is peaked at a photon energy of about 28 MeV, in disagreement with the value recommended by Calarco, Berman, and Donnelly in 1983.Comment: 10 pages, 3 figures, some revisions, submitted to Physics Letters

    A volume inequality for quantum Fisher information and the uncertainty principle

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    Let A1,...,ANA_1,...,A_N be complex self-adjoint matrices and let ρ\rho be a density matrix. The Robertson uncertainty principle det(Covρ(Ah,Aj))det(i2Tr(ρ[Ah,Aj])) det(Cov_\rho(A_h,A_j)) \geq det(- \frac{i}{2} Tr(\rho [A_h,A_j])) gives a bound for the quantum generalized covariance in terms of the commutators [Ah,Aj][A_h,A_j]. The right side matrix is antisymmetric and therefore the bound is trivial (equal to zero) in the odd case N=2m+1N=2m+1. Let ff be an arbitrary normalized symmetric operator monotone function and let ρ,f_{\rho,f} be the associated quantum Fisher information. In this paper we conjecture the inequality det(Covρ(Ah,Aj))det(f(0)2ρ,f) det (Cov_\rho(A_h,A_j)) \geq det (\frac{f(0)}{2} _{\rho,f}) that gives a non-trivial bound for any natural number NN using the commutators i[ρ,Ah]i[\rho, A_h]. The inequality has been proved in the cases N=1,2N=1,2 by the joint efforts of many authors. In this paper we prove the case N=3 for real matrices

    Photoassociation spectroscopy of cold calcium atoms

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    Photoassociation spectroscopy experiments on 40Ca atoms close to the dissociation limit 4s4s 1S0 - 4s4p 1P1 are presented. The vibronic spectrum was measured for detunings of the photoassociation laser ranging from 0.6 GHz to 68 GHz with respect to the atomic resonance. In contrast to previous measurements the rotational splitting of the vibrational lines was fully resolved. Full quantum mechanical numerical simulations of the photoassociation spectrum were performed which allowed us to put constraints on the possible range of the calcium scattering length to between 50 a_0 and 300 a_0
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