Inverse Scattering and Acousto-Optic Imaging

We propose a tomographic method to reconstruct the optical properties of a highly-scattering medium from incoherent acousto-optic measurements. The method is based on the solution to an inverse problem for the diffusion equation and makes use of the principle of interior control of boundary measurements by an external wave field.Comment: 10 page

Operations planning simulation model extension study. Volume 2: Life sciences shuttle laboratory LS-09-S Sortie payload

For abstract, see N75-20432

Operations planning simulation model extension study. Volume 3: Dedicated solar sortie mission SO-01-S sortie payload

For abstract, see N75-20432

Land Of Beautiful Dreams

https://digitalcommons.library.umaine.edu/mmb-vp/5548/thumbnail.jp

Synesthesia on Our Mind

Synesthesia in perception and metaphor in language both provide waysto categorize and comprehend the world. Both operate through mechanisms thatcapitalize on the creation or discovery of links across disparate domains – notably,sensory experiences in different modalities, with cross-modal correspondencesserving as perceptual links in synesthesia and as conceptual links in metaphor.The perceptual links in synesthesia are typically fixed and rigid. The conceptual linksin metaphor, however, enable meanings to expand, creatively, through the activeconstruction of novel, emergent relations: Metaphors transform meanings, therebytranscending the fixed correspondences of synesthesia. Recent evidence associatesthe presence of synesthesia with an augmented capacity for creative cognition.Other evidence associates synesthesia with neural hyperconnectivity – augmentedconnectivity between regions of the cerebral cortex that process the synestheticallylinked domains. We suggest that mechanisms underlying synesthesia may also playa role in processes that foster creative transformations of meanings in metaphor

Using binary statistics in Taurus-Auriga to distinguish between brown dwarf formation processes

Whether BDs form as stars through gravitational collapse ("star-like") or BDs and some very low-mass stars constitute a separate population which form alongside stars comparable to the population of planets, e.g. through circumstellar disk ("peripheral") fragmentation, is one of the key questions of the star-formation problem. For young stars in Taurus-Auriga the binary fraction is large with little dependence on primary mass above ~0.2Msun, while for BDs it is <10%. We investigate a case in which BDs in Taurus formed dominantly through peripheral fragmentation. The decline of the binary frequency in the transition region between star-like and peripheral formation is modelled. A dynamical population synthesis model is employed in which stellar binary formation is universal. Peripheral objects form separately in circumstellar disks with a distinctive initial mass function (IMF), own orbital parameter distributions for binaries and a low binary fraction. A small amount of dynamical processing of the stellar component is accounted for as appropriate for the low-density Taurus-Auriga embedded clusters. The binary fraction declines strongly between the mass-limits for star-like and peripheral formation. The location of characteristic features and the steepness depend on these mass-limits. Such a trend might be unique to low density regions hosting dynamically unprocessed binary populations. The existence of a strong decline in the binary fraction -- primary mass diagram will become verifiable in future surveys on BD and VLMS binarity in the Taurus-Auriga star forming region. It is a test of the (non-)continuity of star formation along the mass-scale, the separateness of the stellar and BD populations and the dominant formation channel for BDs and BD binaries in regions of low stellar density hosting dynamically unprocessed populations.Comment: accepted for publication in A&A, 11 pages, 4 figures, 1 tabl

Multi-frequency fine resolution imaging radar instrumentation and data acquisition

Development of a dual polarized L-band radar imaging system to be used in conjunction with the present dual polarized X-band radar is described. The technique used called for heterodyning the transmitted frequency from X-band to L-band and again heterodyning the received L-band signals back to X-band for amplification, detection, and recording