Comparison of Hyperspectral Imagery Target Detection Algorithm Chains

Detection of a known target in an image has several different approaches. The complexity and number of steps involved in the target detection process makes a comparison of the different possible algorithm chains desirable. Of the different steps involved, some have a more significant impact than others on the final result the ability to find a target in an image. These more important steps often include atmospheric compensation, noise and dimensionality reduction, background characterization, and detection (matched filtering for this research). A brief overview of the algorithms to be compared for each step will be presented. This research seeks to identify the most effective set of algorithms for detecting a known tar get. Several different algorithms for each step will be presented, to include ELM, FLAASH, ACORN, MNF, PPI, N-FINDR, MAXD, and two matched filters that employ a structured background model OSP and ASD. The chains generated by these algorithms will be com pared using the Forest Radiance I HYDICE data set. Finally, ROC curves and AFAR values are calculated for each algorithm chain and a comparison of them is presented. Detection rates at a CFAR are also compared. Since a relatively small number of algorithms were used for each step, there were no definitive results generated. However, a comprehensive comparison of the chains using the above mentioned algorithms is presented

Hybridization of Hyperspectral Imaging Target Detection Algorithm Chains

Detection of a known target in an image can be accomplished using several different approaches. The complexity and number of steps involved in the target detection process makes a comparison of the different possible algorithm chains desirable. Of the different steps involved, some have a more significant impact than others on the final result - the ability to find a target in an image. These more important steps often include atmospheric compensation, noise and dimensionality reduction, background characterization, and detection (matched filtering for this research). A brief overview of the algorithms to be compared for each step will be presented. This research seeks to identify the most effective set of algorithms for a particular image or target type. Several different algorithms for each step will be presented, to include ELM, FLAASH, MNF, PPI, MAXD, the structured background matched filters OSP, and ASD. The chains generated by these algorithms will be compared using the Forest Radiance I HYDICE data set. Finally, receiver operating characteristic (ROC) curves will be calculated for each algorithm chain and, as an end result, a comparison of the various algorithm chains will be presented

Extinction Rates for Fluctuation-Induced Metastabilities : A Real-Space WKB Approach

The extinction of a single species due to demographic stochasticity is analyzed. The discrete nature of the individual agents and the Poissonian noise related to the birth-death processes result in local extinction of a metastable population, as the system hits the absorbing state. The Fokker-Planck formulation of that problem fails to capture the statistics of large deviations from the metastable state, while approximations appropriate close to the absorbing state become, in general, invalid as the population becomes large. To connect these two regimes, a master equation based on a real space WKB method is presented, and is shown to yield an excellent approximation for the decay rate and the extreme events statistics all the way down to the absorbing state. The details of the underlying microscopic process, smeared out in a mean field treatment, are shown to be crucial for an exact determination of the extinction exponent. This general scheme is shown to reproduce the known results in the field, to yield new corollaries and to fit quite precisely the numerical solutions. Moreover it allows for systematic improvement via a series expansion where the small parameter is the inverse of the number of individuals in the metastable state

A rapid non-destructive DNA extraction method for insects and other arthropods

Preparation of arthropods for morphological identification often damages or destroys DNA within the specimen. Conversely, DNA extraction methods often destroy the external physical characteristics essential for morphological identification. We have developed a rapid, simple and non-destructive DNA extraction technique for arthropod specimens. This technique was tested on four arthropod orders, using specimens that were fresh, preserved by air drying, stored in ethanol, or collected with sticky or propylene glycol traps. The technique could be completed in twenty minutes for Coleoptera, Diptera and Hemiptera, and two minutes for the subclass Acarina, without significant distortion, discolouration, or other damage to the specimens

Runaway evaporation for optically dressed atoms

Forced evaporative cooling in a far-off-resonance optical dipole trap is proved to be an efficient method to produce fermionic- or bosonic-degenerated gases. However in most of the experiences, the reduction of the potential height occurs with a diminution of the collision elastic rate. Taking advantage of a long-living excited state, like in two-electron atoms, I propose a new scheme, based on an optical knife, where the forced evaporation can be driven independently of the trap confinement. In this context, the runaway regime might be achieved leading to a substantial improvement of the cooling efficiency. The comparison with the different methods for forced evaporation is discussed in the presence or not of three-body recombination losses

The changing landscape : ecosystem responses to urbanization and pollution across climatic and societal gradients

Author Posting. © Ecological Society of America, 2008. This article is posted here by permission of Ecological Society of America for personal use, not for redistribution. The definitive version was published in Frontiers in Ecology and the Environment 6 (2008): 264–272, doi:10.1890/070147.Urbanization, an important driver of climate change and pollution, alters both biotic and abiotic ecosystem properties within, surrounding, and even at great distances from urban areas. As a result, research challenges and environmental problems must be tackled at local, regional, and global scales. Ecosystem responses to land change are complex and interacting, occurring on all spatial and temporal scales as a consequence of connectivity of resources, energy, and information among social, physical, and biological systems. We propose six hypotheses about local to continental effects of urbanization and pollution, and an operational research approach to test them. This approach focuses on analysis of “megapolitan” areas that have emerged across North America, but also includes diverse wildland-to-urban gradients and spatially continuous coverage of land change. Concerted and coordinated monitoring of land change and accompanying ecosystem responses, coupled with simulation models, will permit robust forecasts of how land change and human settlement patterns will alter ecosystem services and resource utilization across the North American continent. This, in turn, can be applied globally.We thank the NSF LTER program for its support

Photoelectrochemical Behavior of n‑type Si(100) Electrodes Coated with Thin Films of Manganese Oxide Grown by Atomic Layer Deposition

Thin (10 nm) films of manganese oxide have been deposited by atomic layer deposition (ALD) onto n-type silicon and onto degenerately doped p-type silicon. The photoelectrochemical properties of the resulting semiconductor/metal-oxide structures were evaluated in contact with aqueous 0.35 M K_4Fe(CN)_6−0.05 M K_3Fe(CN)_6, 1.0 M KOH(aq), as well as in contact with a series of nonaqueous one electron, reversible, outer-sphere redox systems. Under simulated air mass (AM) 1.5 illumination in contact with 0.35 M K_4Fe(CN)_6−0.05 M K_3Fe(CN)_6(aq), MnO-coated n-Si photoanodes displayed open-circuit voltages of up to 550 mV and stable anodic currents for periods of hours at 0.0 V versus the solution potential. In contact with 1.0 M KOH(aq), at current densities of ∼25 mA cm^(−2), MnO|Si photoanodes under 100 mW cm^(−2) of simulated AM 1.5 illuminationyielded stable oxygen evolution for 10−30 min. Variation in the thickness of the MnO films from 4 to 20 nm indicated the presence of a series resistance in the MnO film that limited the fill factor and thus the solar energy-conversion efficiency of the photoelectrodes. Open-circuit photovoltages of 30 and 450 mV, respectively, were observed in contact with cobaltocene^(+/0) or ferrocene^(+/0) in CH_3CN, indicating that the energetics of the MnO-coated Si surfaces were a function of the electrochemical potential of the contacting electrolyte solution

X-ray properties of radio-selected star forming galaxies in the Chandra-COSMOS survey

X-ray surveys contain sizable numbers of star forming galaxies, beyond the AGN which usually make the majority of detections. Many methods to separate the two populations are used in the literature, based on X-ray and multiwavelength properties. We aim at a detailed test of the classification schemes and to study the X-ray properties of the resulting samples. We build on a sample of galaxies selected at 1.4 GHz in the VLA-COSMOS survey, classified by Smolcic et al. (2008) according to their optical colours and observed with Chandra. A similarly selected control sample of AGN is also used for comparison. We review some X-ray based classification criteria and check how they affect the sample composition. The efficiency of the classification scheme devised by Smolcic et al. (2008) is such that ~30% of composite/misclassified objects are expected because of the higher X-ray brightness of AGN with respect to galaxies. The latter fraction is actually 50% in the X-ray detected sources, while it is expected to be much lower among X-ray undetected sources. Indeed, the analysis of the stacked spectrum of undetected sources shows, consistently, strongly different properties between the AGN and galaxy samples. X-ray based selection criteria are then used to refine both samples. The radio/X-ray luminosity correlation for star forming galaxies is found to hold with the same X-ray/radio ratio valid for nearby galaxies. Some evolution of the ratio may be possible for sources at high redshift or high luminosity, tough it is likely explained by a bias arising from the radio selection. Finally, we discuss the X-ray number counts of star forming galaxies from the VLA- and C-COSMOS surveys according to different selection criteria, and compare them to the similar determination from the Chandra Deep Fields. The classification scheme proposed here may find application in future works and surveys.Comment: 15 pages, 7 figures, 3 table

A synthesis is emerging between biodiversity–ecosystem function and ecological resilience research: reply to Mori

Letter