348 research outputs found
Processing of multispectral thermal IR data for geologic applications
Multispectral thermal IR data were acquired with a 24-channel scanner flown in an aircraft over the E. Tintic Utah mining district. These digital image data required extensive computer processing in order to put the information into a format useful for a geologic photointerpreter. Simple enhancement procedures were not sufficient to reveal the total information content because the data were highly correlated in all channels. The data were shown to be dominated by temperature variations across the scene, while the much more subtle spectral variations between the different rock types were of interest. The image processing techniques employed to analyze these data are described
Evaluation of LANDSAT MSS vs TM simulated data for distinguishing hydrothermal alteration
The LANDSAT Follow-On (LFO) data was simulated to demonstrate the mineral exploration capability of this system for segregating different types of hydrothermal alteration and to compare this capability with that of the existing LANDSAT system. Multispectral data were acquired for several test sites with the Bendix 24-channel MSDS scanner. Contrast enhancements, band ratioing, and principal component transformations were used to process the simulated LFO data for analysis. For Red Mountain, Arizona, the LFO data allowed identification of silicified areas, not identifiable with LANDSAT 1 and 2 data. The improved LFO resolution allowed detection of small silicic outcrops and of a narrow silicified dike. For Cuprite - Ralston, Nevada, the LFO spectral bands allowed discrimination of argillic and opalized altered areas; these could not be spectrally discriminated using LANDSAT 1 and 2 data. Addition of data from the 1.3- and 2.2- micrometer regions allowed better discriminations of hydrothermal alteration types
Color enhancement of landsat agricultural imagery: JPL LACIE image processing support task
Color enhancement techniques were applied to LACIE LANDSAT segments to determine if such enhancement can assist analysis in crop identification. The procedure involved increasing the color range by removing correlation between components. First, a principal component transformation was performed, followed by contrast enhancement to equalize component variances, followed by an inverse transformation to restore familiar color relationships. Filtering was applied to lower order components to reduce color speckle in the enhanced products. Use of single acquisition and multiple acquisition statistics to control the enhancement were compared, and the effects of normalization investigated. Evaluation is left to LACIE personnel
The continual chemical changing aspects in metallurgy production scheduling
Due to keeping the continuous changes of the chemical composition of alloys in the sequence of manufactured products it is required to apply a specific approach at creation of models of production scheduling. The production schedule is created for the workplace continuous process at first, and then the following production schedules of work are derived for another workplaces. The model was implemented in the company RS Slovakia s.r.o
The continual chemical changing aspects in metallurgy production scheduling
Due to keeping the continuous changes of the chemical composition of alloys in the sequence of manufactured products it is required to apply a specific approach at creation of models of production scheduling. The production schedule is created for the workplace continuous process at first, and then the following production schedules of work are derived for another workplaces. The model was implemented in the company RS Slovakia s.r.o
Multi-Wavelength Implications of the Companion Star in Eta Carinae
Eta Carinae is considered to be a massive colliding wind binary system with a
highly eccentric (e \sim 0.9), 5.54-yr orbit. However, the companion star
continues to evade direct detection as the primary dwarfs its emission at most
wavelengths. Using three-dimensional (3-D) SPH simulations of Eta Car's
colliding winds and radiative transfer codes, we are able to compute synthetic
observables across multiple wavebands for comparison to the observations. The
models show that the presence of a companion star has a profound influence on
the observed HST/STIS UV spectrum and H-alpha line profiles, as well as the
ground-based photometric monitoring. Here, we focus on the Bore Hole effect,
wherein the fast wind from the hot secondary star carves a cavity in the dense
primary wind, allowing increased escape of radiation from the hotter/deeper
layers of the primary's extended wind photosphere. The results have important
implications for interpretations of Eta Car's observables at multiple
wavelengths.Comment: 5 pages, 4 figures, To be published in the proceedings of the meeting
'Four Decades of Research on Massive Stars' in honor of Tony Moffat, 11-15
July 2011, Saint-Michel-des-Saints, Quebe
Recommended from our members
USE OF MOLECULAR MODELING TO DETERMINE THE INTERACTION AND COMPETITION OF GASES WITHIN COAL FOR CARBON DIOXIDE SEQUESTRATION
We have made progress in carrying out large scale molecular dynamics simulations using the CHARMM force field in order to refine our coal/guest interactions. There have been two issues facing us over the last year. First, we have had to create a completely new topology and parameter definition for coal. Since we are using a classical force field, we have adopted the strategy of treating coal composed of individual common fragments based upon a distribution of mass, composition, and bonding. Our procedure is similar to treating a protein as being composed of the discrete set of amino acids. Second, we have had to incorporate the quality CO{sub 2} parameters that we have developed over the last two years. There are the geometric and arithmetic procedures, which we have successfully implemented. We have utilized computational molecular modeling to generate a state-of-the-art large scale structural representation of a bituminous coal of low volatile bituminous rank. This structure(s) has been used to investigate the molecular forces between the bituminous coal structure (or idealized pores) and the molecular species CH{sub 4} and CO{sub 2}. We are close to carrying out molecular dynamics simulations, which will allow us to explore and test the newly created model of coal
He II 4686 emission from the massive binary system in Car: constraints to the orbital elements and the nature of the periodic minima
{\eta} Carinae is an extremely massive binary system in which rapid spectrum
variations occur near periastron. Most notably, near periastron the He II
line increases rapidly in strength, drops to a minimum value,
then increases briefly before fading away. To understand this behavior, we
conducted an intense spectroscopic monitoring of the He II
emission line across the 2014.6 periastron passage using ground- and
space-based telescopes. Comparison with previous data confirmed the overall
repeatability of EW(He II ), the line radial velocities, and the
timing of the minimum, though the strongest peak was systematically larger in
2014 than in 2009 by 26%. The EW(He II ) variations, combined
with other measurements, yield an orbital period d. The observed
variability of the EW(He II ) was reproduced by a model in which
the line flux primarily arises at the apex of the wind-wind collision and
scales inversely with the square of the stellar separation, if we account for
the excess emission as the companion star plunges into the hot inner layers of
the primary's atmosphere, and including absorption from the disturbed primary
wind between the source and the observer. This model constrains the orbital
inclination to -, and the longitude of periastron to
-. It also suggests that periastron passage occurred on
d. Our model also reproduced EW(He II )
variations from a polar view of the primary star as determined from the
observed He II emission scattered off the Homunculus nebula.Comment: The article contains 23 pages and 17 figures. It has been accepted
for publication in Ap
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