560 research outputs found
Wide-field LOFAR-LBA power-spectra analyses:Impact of calibration, polarization leakage and ionosphere
Contamination due to foregrounds, calibration errors and ionospheric effects pose major challenges in detection of the cosmic 21 cm signal in various Epoch of Reionization (EoR) experiments. We present the results of a study of a field centered on 3C196 using LOFAR Low Band observations, where we quantify various wide field and calibration effects such as gain errors, polarized foregrounds, and ionospheric effects. We observe a 'pitchfork' structure in the power spectrum of the polarized intensity in delay-baseline space, which leaks into the modes beyond the instrumental horizon. We show that this structure arises due to strong instrumental polarization leakage (∼30%) towards Cas A which is far away from primary field of view. We measure a small ionospheric diffractive scale towards CasA resembling pure Kolmogorov turbulence. Our work provides insights in understanding the nature of aforementioned effects and mitigating them in future Cosmic Dawn observations
The effects of voluntary front-of-pack nutrition labels on volume shares of products:the case of the Dutch choices
AB-QTL analysis in spring barley: III. Identification of exotic alleles for the improvement of malting quality in spring barley ( H. vulgare ssp. spontaneum )
AB-QTL analysis in winter wheat: I. Synthetic hexaploid wheat ( T. turgidum ssp. dicoccoides × T. tauschii ) as a source of favourable alleles for milling and baking quality traits
New method for detecting & measuring cracks on concrete using fiber optic sensors
Advances in the production of optical fibers have made possible the recent development of innovative sensing systems for health monitoring of civil structures. The main reasons for this development are the reduced weight and dimensions of fiber optic sensors, the strong immunity to electromagnetic interference, the improved environmental resistance and the scale flexibility for small-gage and long-gage measurement. This paper provides an overview of the challenges in developing a new fiber optic sensor that can be employed to monitor flexural and tensile cracks on RC structures. The methodology in detecting and localizing the formation of flexural cracks in various locations and sensor’s capability in measuring a range of crack widths is demonstrated through testing of instrumented RC beams subjected to sustained and repeated loading.Fundação para a Ciência e a Tecnologia (FCT
Advanced backcross-QTL analysis in spring barley (H. vulgare ssp. spontaneum) comparing a REML versus a Bayesian model in multi-environmental field
Association of barley photoperiod and vernalization genes with QTLs for flowering time and agronomic traits in a BC2DH population and a set of wild barley introgression lines
Diffraction in low-energy electron scattering from DNA: bridging gas phase and solid state theory
Using high-quality gas phase electron scattering calculations and multiple
scattering theory, we attempt to gain insights on the radiation damage to DNA
induced by secondary low-energy electrons in the condensed phase, and to bridge
the existing gap with the gas phase theory and experiments. The origin of
different resonant features (arising from single molecules or diffraction) is
discussed and the calculations are compared to existing experiments in thin
films.Comment: 40 pages preprint, 12 figures, submitted to J. Chem. Phy
New Exact Solutions of a Generalized Shallow Water Wave Equation
In this work an extended elliptic function method is proposed and applied to
the generalized shallow water wave equation. We systematically investigate to
classify new exact travelling wave solutions expressible in terms of
quasi-periodic elliptic integral function and doubly-periodic Jacobian elliptic
functions. The derived new solutions include rational, periodic, singular and
solitary wave solutions. An interesting comparison with the canonical procedure
is provided. In some cases the obtained elliptic solution has singularity at
certain region in the whole space. For such solutions we have computed the
effective region where the obtained solution is free from such a singularity.Comment: A discussion about singularity and some references are added. To
appear in Physica Script
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