Assessment of the energy efficiency estimation methods on induction motors considering real-time monitoring

Different methods have been developed to estimate the energy efficiency of induction motors. The accuracy of these methods vary with the load factor, the unbalanced voltage (UV) and harmonics. The feasibility of these methods for efficiency estimation in real-time were theoretically and experimentally assessed during the operation under different operational conditions (i.e. balanced sinusoidal voltage (BSV), harmonics, UV and harmonics with UV). Results show that for load factors over 80%, the air-gap method is applicable under any condition, while the slip method is only applicable under BSV or balanced harmonic voltage. Moreover, for load factors over 40%, the nameplate method is applicable under BSV. Other methods result in errors over 8% and optimization methods are not applicable for real-time monitoring. Electric systems generally operates with some degree of UV and harmonics, while induction motors mostly operate with load factors below 60%, limiting the use of these methods for real-time measurement

Al2O3 and Al2O3-ZrO2 Fibers Obtained by Biotemplete with Low Thermal Conductivity

Resumo não disponíve

Urban Park Proposal in Teresina (PI) as a strategy to a Sustainable Urban Development

A urbanização brasileira tem produzido conflitos de diversas naturezas na produção do meio urbano. O presente trabalho visa discutir princípios úteis ao alcance da sustentabilidade no desenvolvimento das cidades, especialmente face à expansão sobre áreas de relevante interesse ambiental em meio urbano. O estudo aborda estratégias de projeto urbano possíveis de responder aos conflitos gerados pela expansão urbana sobre áreas de relevante interesse ambiental. São discutidos conceitos como urbanidade, caminhabilidade e infraestrutura verde, e sua aplicação no âmbito dos espaços livres urbanos. É apresentada uma proposta de parque urbano desenvolvida para área ribeirinha na cidade de Teresina (PI), onde buscou-se implementar os conceitos apresentados e constatar como sua aplicação em nível de projeto colabora para a construção de um desenvolvimento positivo aos olhos da sustentabilidade urbana. O trabalho visa contribuir com conceitos e diretrizes de projeto urbano quando da intervenção em áreas de relevante interesse ambiental.Brazilian urban sprawl has produced conflicts of many types on the production of urban space. This paper aims to discuss usable principles to achieve sustainability on cities urban development, specially facing their sprawl over special interest environment areas located into cities. The study shows strategies to urban designs possible to answering conflicts generated by urban sprawl over special interest environment areas. There are discussed concepts as urbanity, walkability and green infrastructure, and their applicability on urban open spaces. It is presented an urban park proposal developed to a river bank area in the city of Teresina, state of Piauí, where was chased to implement the presented concepts and verify how their implementation on a project collaborates to construct a positive development in the optic of urban sustainability. The paper aims to contribute with concepts and guidelines to urban designs proposed to work with special interest environment areas

Observation of Higgs boson production in association with a top quark pair at the LHC with the ATLAS detector

The observation of Higgs boson production in association with a top quark pair ( tt¯H ), based on the analysis of proton–proton collision data at a centre-of-mass energy of 13 TeV recorded with the ATLAS detector at the Large Hadron Collider, is presented. Using data corresponding to integrated luminosities of up to 79.8 fb −1 , and considering Higgs boson decays into bb¯ , WW⁎ , τ+τ− , γγ , and ZZ⁎ , the observed significance is 5.8 standard deviations, compared to an expectation of 4.9 standard deviations. Combined with the tt¯H searches using a dataset corresponding to integrated luminosities of 4.5 fb −1 at 7 TeV and 20.3 fb −1 at 8 TeV, the observed (expected) significance is 6.3 (5.1) standard deviations. Assuming Standard Model branching fractions, the total tt¯H production cross section at 13 TeV is measured to be 670 ± 90 (stat.) −100+110 (syst.) fb, in agreement with the Standard Model prediction.Peer Reviewe

Measurement of photon–jet transverse momentum correlations in 5.02 TeV Pb + Pb and pppp collisions with ATLAS

Jets created in association with a photon can be used as a calibrated probe to study energy loss in the medium created in nuclear collisions. Measurements of the transverse momentum balance between isolated photons and inclusive jets are presented using integrated luminosities of 0.49 nb$^{-1}$ of Pb+Pb collision data at $\sqrt{s_\mathrm{NN}}=5.02$ TeV and 25 pb$^{-1}$ of $pp$ collision data at $\sqrt{s}=5.02$ TeV recorded with the ATLAS detector at the LHC. Photons with transverse momentum $63.1 31.6$ GeV and pseudorapidity $\left|\eta^\mathrm{jet}\right| 7\pi/8$. Distributions of the per-photon jet yield as a function of $x_\mathrm{J\gamma}$, $(1/N_\gamma)(\mathrm{d}N/\mathrm{d}x_\mathrm{J\gamma})$, are corrected for detector effects via a two-dimensional unfolding procedure and reported at the particle level. In $pp$ collisions, the distributions are well described by Monte Carlo event generators. In Pb+Pb collisions, the $x_\mathrm{J\gamma}$ distribution is modified from that observed in $pp$ collisions with increasing centrality, consistent with the picture of parton energy loss in the hot nuclear medium. The data are compared with a suite of energy-loss models and calculations.Peer Reviewe

Recomendações sobre revascularização do miocárdio

n/

Search for the standard model Higgs boson produced in association with top quarks and decaying into a bbˉb\bar{b} pair in pppp collisions at s\sqrt{s} = 13 TeV with the ATLAS detector

A search for the standard model Higgs boson produced in association with a top-quark pair, tt¯H, is presented. The analysis uses 36.1  fb-1 of pp collision data at s=13  TeV collected with the ATLAS detector at the Large Hadron Collider in 2015 and 2016. The search targets the H→bb¯ decay mode. The selected events contain either one or two electrons or muons from the top-quark decays, and are then categorized according to the number of jets and how likely these are to contain b-hadrons. Multivariate techniques are used to discriminate between signal and background events, the latter being dominated by tt¯+jets production. For a Higgs boson mass of 125 GeV, the ratio of the measured tt¯H signal cross-section to the standard model expectation is found to be μ=0.84-0.61+0.64. A value of μ greater than 2.0 is excluded at 95% confidence level (C.L.) while the expected upper limit is μ<1.2 in the absence of a tt¯H signal.Peer Reviewe

Performance of the ATLAS Track Reconstruction Algorithms in Dense Environments in LHC Run 2

With the increase in energy of the Large Hadron Collider to a centre-of-mass energy of 13  $\text {TeV}$ for Run 2, events with dense environments, such as in the cores of high-energy jets, became a focus for new physics searches as well as measurements of the Standard Model. These environments are characterized by charged-particle separations of the order of the tracking detectors sensor granularity. Basic track quantities are compared between 3.2 fb$^{-1}$ of data collected by the ATLAS experiment and simulation of proton–proton collisions producing high-transverse-momentum jets at a centre-of-mass energy of 13  $\text {TeV}$ . The impact of charged-particle separations and multiplicities on the track reconstruction performance is discussed. The track reconstruction efficiency in the cores of jets with transverse momenta between 200 and 1600 $\text {GeV}$ is quantified using a novel, data-driven, method. The method uses the energy loss, ${\text { d}}{} \textit{E}/d\textit{x}$ , to identify pixel clusters originating from two charged particles. Of the charged particles creating these clusters, the measured fraction that fail to be reconstructed is $0.061 \pm 0.006\ {\text {(stat.)}} \pm 0.014\ {\text {(syst.)}}$ and $0.093 \pm 0.017\ {\text {(stat.)}}\pm 0.021\ {\text {(syst.)}}$ for jet transverse momenta of 200–400  $\text {GeV}$ and 1400–1600  $\text {GeV}$ , respectively.Peer Reviewe

Combined search for the Standard Model Higgs boson in pppp collisions at s=7\sqrt{s} = 7 TeV with the ATLAS detector

A combined search for the Standard Model Higgs boson with the ATLAS detector at the LHC is presented. The datasets used correspond to integrated luminosities from 4.6 fb^-1 to 4.9 fb^-1 of proton-proton collisions collected at sqrt(s) = 7 TeV in 2011. The Higgs boson mass ranges of 111.4 GeV to 116.6 GeV, 119.4 GeV to 122.1 GeV, and 129.2 GeV to 541 GeV are excluded at the 95% confidence level, while the range 120 GeV to 560 GeV is expected to be excluded in the absence of a signal. An excess of events is observed at Higgs boson mass hypotheses around 126 GeV with a local significance of 2.9 standard deviations (sigma). The global probability for the background to produce an excess at least as significant anywhere in the entire explored Higgs boson mass range of 110-600 GeV is estimated to be ~15%, corresponding to a significance of approximately one sigma.Peer Reviewe

Measurement of the cross section for isolated-photon plus jet production in pppp collisions at s=13\sqrt s=13 TeV using the ATLAS detector

The dynamics of isolated-photon production in association with a jet in proton–proton collisions at a centre-of-mass energy of 13 TeV are studied with the ATLAS detector at the LHC using a dataset with an integrated luminosity of 3.2 fb −1 . Photons are required to have transverse energies above 125 GeV. Jets are identified using the anti- kt algorithm with radius parameter R=0.4 and required to have transverse momenta above 100 GeV. Measurements of isolated-photon plus jet cross sections are presented as functions of the leading-photon transverse energy, the leading-jet transverse momentum, the azimuthal angular separation between the photon and the jet, the photon–jet invariant mass and the scattering angle in the photon–jet centre-of-mass system. Tree-level plus parton-shower predictions from Sherpa and Pythia as well as next-to-leading-order QCD predictions from Jetphox and Sherpa are compared to the measurements.Peer Reviewe