Search results for " GAP"
showing 10 items of 811 documents
The electronic properties of SrTiO3-δ with oxygen vacancies or substitutions
2021
The authors would like to thank R. Dittmann for useful discussions, T. Kocourek, O. Pacherova, S. Cichon, V. Vetokhina, and P. Babor for their contributions to sample preparation and characterization. The authors (M.T., A.D.) acknowledge support from the Czech Science Foundation (Grant No. 19-09671S), the European Structural and Investment Funds and the Ministry of Education, Youth and Sports of the Czech Republic through Programme “Research, Development and Education” (Project No. SOLID21 CZ.02.1.01/0.0/0.0/16-019/0000760). This study was partly supported by FLAG-ERA JTC project To2Dox (L.R. and E.K.). Calculations have been performed on the LASC Cluster in the Institute of Solid State Phy…
Creating stable Floquet–Weyl semimetals by laser-driving of 3D Dirac materials
2017
Nature Communications 8, 13940 (2017). doi:10.1038/ncomms13940
Evaluation of vapor mass transfer in various membrane distillation configurations: an experimental study
2011
Vapor mass transfer phenomena in four different membrane distillation (MD) configurations were examined through a self-built laboratory scale experimen- tal apparatus: Air Gap MD, Sweeping Gas MD, Vacuum Sweeping Gas MD and Vacuum MD. Vapor fluxes were measured and compared with those predicted by various models, showing that MD performance under usual processing conditions is severely controlled by the permeate side resistance to mass transfer.
School choice criteria and school segregation in the city of Valencia
2022
El objetivo de este estudio es conocer cuáles son los patrones que intervienen en la elección de centro escolar y detectar los factores sociodemográficos, económicos y de localización que subyacen tras ellos. Para ello, se ha realizado una encuesta a la demanda potencial de los centros públicos que imparten el segundo ciclo de educación infantil en la ciudad de Valencia. Los resultados indican que el principal criterio de elección de centro escolar es la proximidad entre el hogar y el colegio, y que el modo de desplazamiento más utilizado es el peatonal. Sin embargo, los costes de desplazamiento y los medios utilizados están directamente relacionados con las características socioeconómicas …
Internal photoemission in solar blind AlGaN Schottky barrier photodiodes
2005
We have analyzed the photoresponse of solar blind AlGaN Schottky barrier photodiodes below the alloy band gap energy, in the 3.5-4.5 eV range, and we show that it is dominated by internal photoemission. The n-type Schottky barrier height is shown to increase linearly with the band gap energy of the AlGaN alloy. The amplitude of the internal photoemission signal is about 20 times smaller than the value given by the Fowler theory based on a free electron model. We explain this result by taking into account the interband transitions and the ballistic transport of photoexcited electrons in the metal. This low value of internal photoemission allows us to achieve a spectral rejection ratio betwee…
Characterization of clamp-on current transformers under nonsinusoidal conditions
2009
This paper reports the performance of clamp-on current transformers under nonsinusoidal conditions. A set of experimental measurements helped to determine the ratio and the phase errors under two conditions: 1) sinusoidal excitation with frequencies from 45 to 1000 Hz and 2) nonsinusoidal excitation using the fundamental frequency and one harmonic, with adjusted phase shift. It was found that ratio and phase errors are affected by the phase angle between the harmonic and the fundamental and the harmonic amplitude. The effects of conductor location in the current transformer's window and of the air-gap width were also investigated. It was concluded that harmonic phase and ratio errors measur…
Quantum gap and spin-wave excitations in the Kitaev model on a triangular lattice
2017
We study the effects of quantum fluctuations on the dynamical generation of a gap and on the evolution of the spin-wave spectra of a frustrated magnet on a triangular lattice with bond-dependent Ising couplings, analog of the Kitaev honeycomb model. The quantum fluctuations lift the subextensive degeneracy of the classical ground-state manifold by a quantum order-by-disorder mechanism. Nearest-neighbor chains remain decoupled and the surviving discrete degeneracy of the ground state is protected by a hidden model symmetry. We show how the four-spin interaction, emergent from the fluctuations, generates a spin gap shifting the nodal lines of the linear spin-wave spectrum to finite energies.
Comparing Spatial and Spatio-temporal FPCA to Impute Large Continuous Gaps in Space
2018
Multivariate spatio-temporal data analysis methods usually assume fairly complete data, while a number of gaps often occur along time or in space. In air quality data long gaps may be due to instrument malfunctions; moreover, not all the pollutants of interest are measured in all the monitoring stations of a network. In literature, many statistical methods have been proposed for imputing short sequences of missing values, but most of them are not valid when the fraction of missing values is high. Furthermore, the limitation of the methods commonly used consists in exploiting temporal only, or spatial only, correlation of the data. The objective of this paper is to provide an approach based …
The minimum pension and its effect on the gender gap in retirement pensions in Spain
2021
The gender gap in pensions is greater than the gender gap in wages in the majority of countries in the European Union. Similarly, more women live on a minimum pension than do men. Therefore, the me...
Occupazione, profitto e capabilities in una professione tradizionalmente femminile
2021
Questo saggio si propone di fare una ricognizione degli studi che in Italia, a partire dagli anni Sessanta, hanno trattato il tema del Servizio sociale e della propria identità di genere. A tale scopo viene svolta una desk analysis e una literature review sul tema dei livelli occupazionali degli assistenti sociali che si incrocia inevitabilmente con quello del genere. Sotteso al tema occupazionale è quello ben più spinoso del posizionamento di ruolo negli organigrammi lavorativi dei professionisti e delle professioniste. La tematizzazione critica del gender mainstreaming come strategia di policy making interseca, infatti, il rapporto tra democrazia e potere, insieme alle ricadute e le impli…