199 research outputs found
AS-204/LM-1 launch vehicle operational flight trajectory
Apollo Saturn-204/LM-1 launch vehicle operational flight trajector
AS-204/LM-1 L/V operational alternate mission trajectories
Operational alternate mission trajectories of AS-204 LM-1 launch vehicl
Hyperspectral imaging of cuttlefish camouflage indicates good color match in the eyes of fish predators
Author Posting. © The Author(s), 2011. This is the author's version of the work. It is posted here by permission of National Academy of Sciences for personal use, not for redistribution. The definitive version was published in Proceedings of the National Academy of Sciences of the United States of America 108 (2011):9148-9153, doi:10.1073/pnas.1019090108.Camouflage is a widespread phenomenon throughout nature and an important
anti-predator tactic in natural selection. Many visual predators have keen color
perception, thus camouflage patterns should provide some degree of color matching in
addition to other visual factors such as pattern, contrast, and texture. Quantifying
camouflage effectiveness in the eyes of the predator is a challenge from the
perspectives of both biology and optical imaging technology. Here we take advantage
of Hyperspectral Imaging (HSI), which records full-spectrum light data, to
simultaneously visualize color match and pattern match in the spectral and the spatial
domains, respectively. Cuttlefish can dynamically camouflage themselves on any
natural substrate and, despite their colorblindness, produce body patterns that appear
to have high-fidelity color matches to the substrate when viewed directly by humans
or with RGB images. Live camouflaged cuttlefish on natural backgrounds were
imaged using HSI, and subsequent spectral analysis revealed that most reflectance
spectra of individual cuttlefish and substrates were similar, rendering the color match
possible. Modeling color vision of potential di- and tri-chromatic fish predators of
cuttlefish corroborated the spectral match analysis and demonstrated that camouflaged
cuttlefish show good color match as well as pattern match in the eyes of fish predators.
These findings (i) indicate the strong potential of HSI technology to enhance studies
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of biological coloration, and (ii) provide supporting evidence that cuttlefish can
produce color-coordinated camouflage on natural substrates despite lacking color
vision.We gratefully acknowledge financial support from the
National Science Council of Taiwan NSC-98-2628-B-007-001-MY3 to CCC, from
the Network Science Center at West Point and the Army Research Office to JKW,
from the NDSEG Fellowship to JJA, and from ONR grant N000140610202 to RTH
Fear Learning for Flexible Decision Making in RoboCup: A Discussion
In this paper, we address the stagnation of RoboCup com- petitions in the fields of contextual perception, real-time adaptation and flexible decision-making, mainly in regards to the Standard Platform League (SPL). We argue that our Situation-Aware FEar Learning (SAFEL) model has the necessary tools to leverage the SPL competition in these fields of research, by allowing robot players to learn the behaviour profile of the opponent team at runtime. Later, players can use this knowledge to predict when an undesirable outcome is imminent, thus having the chance to act towards preventing it. We discuss specific scenarios where SAFEL’s associative learning could help to increase the positive outcomes of a team during a soccer match by means of contextual adaptation
Telavancin versus Vancomycin for Hospital-Acquired Pneumonia due to Gram-positive Pathogens
The results from two methodologically identical double-blind studies indicate that telavancin is noninferior to vancomycin based on clinical response in the treatment of hospital-acquired pneumonia due to Gram-positive pathogens
Estimating food production in an urban landscape
There is increasing interest in urban food production for reasons of food security, environmental sustainability, social and health benefits. In developed nations urban food growing is largely informal and localised, in gardens, allotments and public spaces, but we know little about the magnitude of this production. Here we couple own-grown crop yield data with garden and allotment areal surveys and urban fruit tree occurrence to provide one of the first estimates for current and potential food production in a UK urban setting. Current production is estimated to be sufficient to supply the urban population with fruit and vegetables for about 30 days per year, while the most optimistic model results suggest that existing land cultivated for food could supply over half of the annual demand. Our findings provide a baseline for current production whilst highlighting the potential for change under the scaling up of cultivation on existing land
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