5,906 research outputs found
Method and apparatus for providing a seamless tiled display
A display for producing a seamless composite image from at least two discrete images. The display includes one or more projectors for projecting each of the discrete images separately onto a screen such that at least one of the discrete images overlaps at least one other of the discrete images by more than 25 percent. The amount of overlap that is required to reduce the seams of the composite image to an acceptable level over a predetermined viewing angle depends on a number of factors including the field-of-view and aperture size of the projectors, the screen gain profile, etc. For rear-projection screens and some front projection screens, an overlap of more than 25 percent is acceptable
THIRD INTERNATIONAL SYMPOSIUM ON RANAVIRUSES:: ADVANCING THE UNDERSTANDING OF THE THREAT OF RANAVIRUSES TO NORTH AMERICAN HERPETOFAUNA
Members of the genus Ranavirus, one of five genera withinthe family Iridoviridae, encompass a group of large, doublestrandedDNA viruses that infect all three classes of ectothermicvertebrates: fish, amphibians, and reptiles. Ranaviruses areglobally emerging pathogens that cause considerable morbidityand mortality among diverse populations. In North America,ranavirus epizootics are regularly reported in wild and culturedfish, amphibian, and reptile populations
Extending Johnson's and Morita's homomorphisms to the mapping class group
We extend certain homomorphisms defined on the higher Torelli subgroups of
the mapping class group to crossed homomorphisms defined on the entire mapping
class group. In particular, for every , we construct a crossed
homomorphism which extends Morita's homomorphism
to the entire mapping class group. From this crossed homomorphism we also
obtain a crossed homomorphism extending the th Johnson homomorphism
to the mapping class group.
D. Johnson and S. Morita obtained their respective homomorphisms by
considering the action of the mapping class group on the nilpotent truncations
of the surface group; our approach is to mimic Morita's construction
topologically by using nilmanifolds associated to these truncations. This
allows us to take the ranges of these crossed homomorphisms to be certain
finite-dimensional real vector spaces associated to these nilmanifolds.Comment: 32 pages; cleaned up and minor corrections to proofs; updated to
agree with version published by Alg. & Geom. Top at:
http://msp.warwick.ac.uk/agt/2007/07/p050.xhtm
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