728 research outputs found
Principal components technique analysis for vegetation and land use discrimination
Automatic pre-processing technique called Principal Components (PRINCO) in analyzing LANDSAT digitized data, for land use and vegetation cover, on the Brazilian cerrados was evaluated. The chosen pilot area, 223/67 of MSS/LANDSAT 3, was classified on a GE Image-100 System, through a maximum-likehood algorithm (MAXVER). The same procedure was applied to the PRINCO treated image. PRINCO consists of a linear transformation performed on the original bands, in order to eliminate the information redundancy of the LANDSAT channels. After PRINCO only two channels were used thus reducing computer effort. The original channels and the PRINCO channels grey levels for the five identified classes (grassland, "cerrado", burned areas, anthropic areas, and gallery forest) were obtained through the MAXVER algorithm. This algorithm also presented the average performance for both cases. In order to evaluate the results, the Jeffreys-Matusita distance (JM-distance) between classes was computed. The classification matrix, obtained through MAXVER, after a PRINCO pre-processing, showed approximately the same average performance in the classes separability
Atmospheric correction analysis on LANDSAT data over the Amazon region
The Amazon Region natural resources were studied in two ways and compared. A LANDSAT scene and its attributes were selected, and a maximum likelihood classification was made. The scene was atmospherically corrected, taking into account Amazonic peculiarities revealed by (ground truth) of the same area, and the subsequent classification. Comparison shows that the classification improves with the atmospherically corrected images
Sensitivity to the KARMEN Timing Anomaly at MiniBooNE
We present sensitivities for the MiniBooNE experiment to a rare exotic pion
decay producing a massive particle, Q^0. This type of decay represents one
possible explanation for the timing anomaly reported by the KARMEN
collaboration. MiniBooNE will be able to explore an area of the KARMEN signal
that has not yet been investigated
Solar Neutrinos from CNO Electron Capture
The neutrino flux from the sun is predicted to have a CNO-cycle contribution
as well as the known pp-chain component. Previously, only the fluxes from beta+
decays of 13N, 15O, and 17F have been calculated in detail. Another neutrino
component that has not been widely considered is electron capture on these
nuclei. We calculate the number of interactions in several solar neutrino
detectors due to neutrinos from electron capture on 13N, 15O, and 17F, within
the context of the Standard Solar Model. We also discuss possible non-standard
models where the CNO flux is increased.Comment: 4 pages, 1 figure, submitted to Phys. Rev. C; v2 has minor changes
including integration over solar volume and addition of missing reference to
previous continuum electron capture calculation; v3 has minor changes
including addition of references and the correction of a small (about 1%)
numerical error in the table
Observation of an Anomalous Number of Dimuon Events in a High Energy Neutrino Beam
A search for long-lived neutral particles (N^0's) with masses above 2.2
GeV/c^2 that decay into at least one muon has been performed using an
instrumented decay channel at the NuTeV experiment at Fermilab. Data were
examined for particles decaying into the final states mu mu, mu e, and mu pi.
Three mu mu events were observed over an expected Standard Model background of
0.069 +/- 0.010 events; no events were observed in the other modes.Comment: 5 pages, 3 figures, Submitted to Phys. Rev. Let
Snowmass 2021 Topical Report on Synergies in Research at Underground Facilities
This is a Snowmass 2021 Topical Report for the Underground Facilities and
Infrastructure Frontier on Synergies in Research at Underground Facilities: A
broad range of scientific and engineering research is possible in underground
laboratories, beyond the physics-focused activities described in the other
Underground Facilities and Infrastructure Topical Reports. These areas of
research include nuclear astrophysics, geology, geoengineering, gravitational
wave detection, biology, and perhaps soon quantum information science. This UF
Topical Report will survey those other scientific and engineering research
activities that share interest in research-orientated Underground Facilities
and Infrastructure. In most cases the breadth and depth of research aims is too
large to cover in completeness and references to surveys or key documents for
those fields are provided after introductory summaries. Additional attention is
then given to shared, similar, and unique needs of each research area with
respect to the broader underground research community's Underground Facilities
and Infrastructure needs. Where potential conflicts of usage type, site, or
duration might arise, these are identified.Comment: Snowmass 2021 Topical Report (UF5
Using Landsat 8 image time series for crop mapping in a region of Cerrado, Brazil.
Abstract: The objective of this research is to classify agricultural land use in a region of the Cerrado (Brazilian Savanna) biome using a time series of Enhanced Vegetation Index (EVI) from Landsat 8 OLI. Phenological metrics extracted from EVI time series, a Random Forest algorithm and data mining techniques are used in the process of classification. The area of study is a region in the Cerrado in a region of the municipality of Casa Branca, São Paulo state, Brazil. The results are encouraging and demonstrate the potential of phenological parameters obtained from time series of OLI vegetation indices for agricultural land use classification
A Prototype Detector for Directional Measurement of the Cosmogenic Neutron Flux
This paper describes a novel directional neutron detector prototype. The low
pressure time projection chamber uses a mix of helium and CF4 gases. The
detector reconstructs the energy and angular distribution of fast neutron
recoils. This paper reports results of energy calibration using an alpha source
and angular reconstruction studies using a collimated neutron source. The best
performance is obtained with a 12.5% CF4 gas mixture. At low energies the
target for fast neutrons transitions is primarily helium, while at higher
energies, the fluorine contributes as a target. The reconstruction efficiency
is both energy and target dependent. For neutrons with energies less than 20
MeV, the reconstruction efficiency is ~40% for fluorine recoils and ~60% for
helium recoils.Comment: final versio
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