Search results for "frequencie"
showing 10 items of 34 documents
Microwave harmonic emission in MgB2 superconductor: Comparison with YBA2CU3O7
2006
We report results of microwave second-harmonic generation in ceramic samples of MgB2, prepared by different methods. The SH signal has been investigated as a function of the temperature and the static magnetic field. The results are discussed in the framework of models reported in the literature. We show that the peculiarities of the SH signal are related to the specific properties of the sample. A comparison with the results obtained in ceramic and crystalline YBa2Cu3O7 shows that the second-harmonic emission in MgB2 is weaker than that observed in ceramic YBa2CuO7. (c) 2006 Wiley Periodicals, Inc.
Improvement of Hall Effect Current Transducer Metrological Performances in the Presence of Harmonic Distortion
2010
The performance of Hall effect current transducers (HECTs), under distorted waveform conditions, is usually characterized by means of a frequency response test. In this paper, it was investigated if frequency response is able to correctly evaluate the ratio and the phase errors under distorted conditions. Two HECTs, with the accuracy class level of 1% and 0.5%, respectively, were experimentally characterized under two conditions: 1) sinusoidal excitation with frequencies ranging from 50 to 750 Hz, which is the well-known frequency response test, and 2) nonsinusoidal excitation using fundamental frequency and one harmonic with adjusted amplitude and phase shift. It was found that ratio and p…
Prion protein gene frequencies in three Sicilian dairy sheep populations
2008
The objective of this paper was to investigate the prion protein (PrP) genotype and haplotype frequencies in three Sicilian dairy sheep populations. The three populations were: (1) 1096 Valle del Belice animals, (2) 1143 Comisana animals, and (3) 1771 individuals from 5 flocks with scrapie outbreaks, in which the animals were crossbreds derived from indigenous Sicilian dairy breeds. PrP genotypes are described for the three codons 136 (Alanine or Valine; A, V), 154 (Histidine or Arginine; H, R), and 171 (Glutamine, Arginine or Histidine; Q, R, H) which represent polymorphisms known to be linked with scrapie susceptibility. The Valle del Belice haplotype frequencies were 32.3% ARR, 6.5% AHQ,…
Anharmonicity modeling in hydrogen bonded solvent dimers
2021
Abstract Harmonic and anharmonic frequencies of dimers and mixed dimers of water, methanol and benzene were computed and the results were critically analysed to investigate the anharmonicity of the normal mode vibrations within density functional theory (DFT) with empirically included Grimme correction for dispersion (D3). From several options, the B3LYP-D3/6-31++G* level of theory was selected as a good compromise between accuracy and calculation speed, suitable for future modeling of larger solvent clusters. The obtained raw harmonic and anharmonic second-order perturbation theory of vibrational frequencies (VPT2) were additionally scaled using a two-range procedure (below and above 2000 …
An AC-assisted single-nanowire electromechanical switch
2013
A unique two-source controlled nanoelectromechanical switch has been assembled from individual, single-clamped Ge nanowires. The switching behaviour was achieved by superimposing the control signals of specific frequencies to the electrostatic potential of the output terminals, eliminating the need for an additional gate electrode. Using an in situ manipulation technique inside a scanning electron microscope, we demonstrate that the pull-out force required to overcome adhesion at the contact can be significantly reduced by exciting mechanical resonant modes within the nanowire.
Using a Multi-Locus Microsatellite Typing method improved phylogenetic distribution of Candida albicans isolates but failed to demonstrate associatio…
2012
EA MERS CT3 Enjeu 3; International audience; The dimorphic yeast Candida albicans is a component of the normal microflora at the mucosal surfaces of healthy individuals. It possesses an array of phenotypic properties considered as virulence traits that contribute to pathogenicity of the yeast in immuno-compromised patients. We addressed the question of the pathogenicity of lineages of C. albicans with regard to their genotype in three series of C. albicans isolates (a series of commensal isolates collected in healthy individuals, a group of bloodstream isolates and a group of non-bloodstream clinical isolates) using a Multi-Locus Microsatellite Typing (MLMT) approach based on the analysis o…
Phenotypical and functional analysis of memory and effector human CD8 T cells specific for mycobacterial antigens
2006
Abstract Mycobacterium tuberculosis infects one-third of the global population and claims two million lives every year. Because memory CD8 T cells exhibit a high heterogeneity in terms of phenotype and functional characteristic, we investigated the frequency, phenotype, and functional properties of Ag85A epitope-specific HLA-A*0201 CD8 T cells in children affected by tuberculosis (TB) before and 4 mo after chemotherapy and healthy contact children. Using Ag85A peptide/HLA-A*0201 pentamer, we found a low frequency of blood peptide-specific CD8 T cells in tuberculous children before therapy, which consistently increased after therapy to levels detected in healthy contacts. Ex vivo analysis of…
Robustness of Empirical Vibration Correlation Techniques for Predicting the Instability of Unstiffened Cylindrical Composite Shells in Axial Compress…
2020
Thin-walled carbon fiber reinforced plastic (CFRP) shells are increasingly used in aerospace industry. Such shells are prone to the loss of stability under compressive loads. Furthermore, the instability onset of monocoque shells exhibits a pronounced imperfection sensitivity. The vibration correlation technique (VCT) is being developed as a nondestructive test method for evaluation of the buckling load of the shells. In this study, accuracy and robustness of an existing and a modified VCT method are evaluated. With this aim, more than 20 thin-walled unstiffened CFRP shells have been produced and tested. The results obtained suggest that the vibration response under loads exceeding 0.25 of …
Optical Probing (EOFM/TRI): A large set of complementary applications for ultimate VLSI
2013
International audience; Electro Optical Techniques (EOFM: Electro Optical Frequency Mapping and EOP: Electro Optical Probing) and Dynamic Light Emission Techniques (TRE: Time Resolved Emission and TRI: Time Resolved Imaging) are dynamic optical probing techniques widely used at IC level for design debug and defect localization purpose. They can pinpoint the origin of timing issue or logic fault in up to date CMOS devices. Each technique has its advantages and its drawbacks allowing a common set of applications and more specific ones. We have been involved in the development of the most advanced techniques related to EOFM and TRI on various devices (down to 28nm technology). What we can expe…
Relationship of Weather Types on the Seasonal and Spatial Variability of Rainfall, Runoff, and Sediment Yield in the Western Mediterranean Basin
2020
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