58,891 research outputs found
Towards a knowledge-based system to assist the Brazilian data-collecting system operation
A study is reported which was carried out to show how a knowledge-based approach would lead to a flexible tool to assist the operation task in a satellite-based environmental data collection system. Some characteristics of a hypothesized system comprised of a satellite and a network of Interrogable Data Collecting Platforms (IDCPs) are pointed out. The Knowledge-Based Planning Assistant System (KBPAS) and some aspects about how knowledge is organized in the IDCP's domain are briefly described
Transmission coefficient and two-fold degenerate discrete spectrum of spin-1 bosons in a double-step potential
The scattering of spin-1 bosons in a nonminimal vector double-step potential
is described in terms of eigenstates of the helicity operator and it is shown
that the transmission coefficient is insensitive to the choice of the
polarization of the incident beam. Poles of the transmission amplitude reveal
the existence of a two-fold degenerate spectrum. The results are interpreted in
terms of solutions of two coupled effective Schr\"{o}dinger equations for a
finite square well with additional -functions situated at the borders.Comment: arXiv admin note: substantial text overlap with arXiv:1203.119
Near-infrared study of new embedded clusters in the Carina complex
We analyse the nature of a sample of stellar overdensities that we found
projected on the Carina complex. This study is based on 2MASS photometry and
involves the photometry decontamination of field stars, elaboration of
intrinsic colour-magnitude diagrams J(J-Ks), colour-colour diagrams
(J-H)(H-Ks) and radial density profiles, in order to determine the
structure and the main astrophysical parameters of the best candidates. The
verification of an overdensity as an embedded cluster requires a CMD consistent
with a PMS content and MS stars, if any. From these results, we are able to
verify if they are, in fact, embedded clusters. The results were, in general,
rewarding: in a sample of 101 overdensities, the analysis provided 15
candidates, of which three were previously catalogued as clusters
(CCCP-Cl16, Treasure Chest and FSR1555), and the 12 remaining are
discoveries that provided significant results, with ages not above 4.5Myr
and distances compatible with the studied complex. The resulting values for the
differential reddening of most candidates were relatively high, confirming that
these clusters are still (partially or fully) embedded in the surrounding gas
and dust, as a rule within a shell. Histograms with the distribution of the
masses, ages and distances were also produced, to give an overview of the
results. We conclude that all the 12 newly found embedded clusters are related
to the Carina complex.Comment: 10 pages, 14 figures, accepted for publication in MNRA
Dimensionamento de piquetes para bovinos leiteiros, em sistemas de pastejo rotacionado.
bitstream/CPPSE/16797/1/Comunicado-Tecnico-65.pd
Produção de forragem e composição botânica de três espécies de pastagens tropicais sobressemeadas com aveia ou azevém.
O uso da sobressemeadura com espécies temperadas sobre pastagens tropicais apresenta vantagens técnicas e econômicas. Entretanto, a combinação entre as espécies necessita de mais estudos. Este trabalho teve por objetivo estudar nove combinações de espécies sobre a produção de forragem e composição botânica da pastagem. A Brachiaria brizantha cv. Marandu foi a espécie mais adaptada a sobressemeadura, permitindo que 50% do total de forragem colhida fosse representado pelas espécies temperadas (aveia ou azevém). O capim Coastcross produziu muita forragem na época seca, fato que permitiu 20% apenas de porcentagem de forragem da espécie temperada
Seleção preliminar de cultivares de alfafa sob pastejo em condições tropicais, no município de São Carlos, SP.
bitstream/CPPSE/16792/1/Comunicado-Tecnico-68.pd
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