2,767 research outputs found
Management of the Rice Tungro Virus Vector \u3ci\u3eNephotettix virescens\u3c/i\u3e (Homoptera: Cicadellidae) with Controlled-Release Formulations of Carbofuran
Field trials were conducted in lowland flooded rice in the Philippines to evaluate a number of carbofuran controlled-release formulations in comparison with commercial formulations. The test formulations were based on a biodegradable matrix of pine kraft lignin and were used as granules of different sizes and also in the form of small strips. The release rates were assessed under field conditions by bioassaying rice plants in the field, using adult rice green leafhopper, Nephotettix virescens Distant. The lignin formulations with a high level of active ingredient (15â45% by weight) gave as good or better control than the commercial 3% granules in tests based on three application techniques: broadcast into the floodwater, soil incorporation, and root zone injection. The improvements in control levels of green leafhoppers were most marked with soil incorporation and root zone application. The best lignin-based formulation reduced levels of tungro virus infection from 23% for a conventional flowable carbofuran formulation to 1.0% at an application rate of 0.5 kg (AI)/ha. At the same rate, the grain yield was increased from 3.56 t/ha to 5.5 t/ha, using the controlled-released formulation
Characterization of Vehicle Behavior with Information Theory
This work proposes the use of Information Theory for the characterization of
vehicles behavior through their velocities. Three public data sets were used:
i.Mobile Century data set collected on Highway I-880, near Union City,
California; ii.Borl\"ange GPS data set collected in the Swedish city of
Borl\"ange; and iii.Beijing taxicabs data set collected in Beijing, China,
where each vehicle speed is stored as a time series. The Bandt-Pompe
methodology combined with the Complexity-Entropy plane were used to identify
different regimes and behaviors. The global velocity is compatible with a
correlated noise with f^{-k} Power Spectrum with k >= 0. With this we identify
traffic behaviors as, for instance, random velocities (k aprox. 0) when there
is congestion, and more correlated velocities (k aprox. 3) in the presence of
free traffic flow
Structural Changes in Data Communication in Wireless Sensor Networks
Wireless sensor networks are an important technology for making distributed
autonomous measures in hostile or inaccessible environments. Among the
challenges they pose, the way data travel among them is a relevant issue since
their structure is quite dynamic. The operational topology of such devices can
often be described by complex networks. In this work, we assess the variation
of measures commonly employed in the complex networks literature applied to
wireless sensor networks. Four data communication strategies were considered:
geometric, random, small-world, and scale-free models, along with the shortest
path length measure. The sensitivity of this measure was analyzed with respect
to the following perturbations: insertion and removal of nodes in the geometric
strategy; and insertion, removal and rewiring of links in the other models. The
assessment was performed using the normalized Kullback-Leibler divergence and
Hellinger distance quantifiers, both deriving from the Information Theory
framework. The results reveal that the shortest path length is sensitive to
perturbations.Comment: 12 pages, 4 figures, Central European Journal of Physic
Estoques de carbono e nutrientes e macrofauna invertebrada em argissolo sob sistemas agroflorestais e agricultura de corte e queima no norte do PiauĂ.
bitstream/item/83415/1/CT2020001.pd
Rural-urban migration in d-dimensional lattices
The rural-urban migration phenomenon is analyzed by using an agent-based
computational model. Agents are placed on lattices which dimensions varying
from d=2 up to d=7. The localization of the agents in the lattice define their
social neighborhood (rural or urban) not being related to their spatial
distribution. The effect of the dimension of lattice is studied by analyzing
the variation of the main parameters that characterizes the migratory process.
The dynamics displays strong effects even for around one million of sites, in
higher dimensions (d=6, 7).Comment: 9 pages, 7 figures, to be published in International Journal of
Modern Physics C 1
Solos e aptidĂŁo edafoclimĂĄtica para a cultura do cajueiro no MunicĂpio de GrajaĂș-MA.
bitstream/CNPAT-2010/5591/1/Ct-036.pd
Correção do solo para cultivo do cajueiro no cerrado piauiense.
Caracteristicas dos solos cultivados com cajueiro no Piaui; Correcao do solo; Recomendacoesbitstream/CNPAT-2010/8606/1/Dc-081.pd
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