3,459 research outputs found
IRAS observations of the ISM in the gamma CAS reflection nebula
Mid-infrared emission from other galaxies originates both from interstellar grains heated by diffuse starlight and local excitation of grains by hot OB stars. Thus, a detailed examination of the Infrared Astronomy Satellite (IRAS) data from a B star interacting with the interstellar medium (ISM) could provide insight into infrared (IR) emission processes in external galaxies. Researchers have therefore used IRAS data to study the B0 IVe star gamma Cas and its surroundings, which they find to exhibit evidence of grain heating, destruction, and possible star formation
NASA/MSFC Large Stretch Press Study
The purpose of this study was to: A. assess and document the advantages/disadvantages of a government agency investment in a large stretch form press on the order of 5000 tons capacity (per jaw); B. develop a procurement specification for the press; and C. provide trade study data that will permit an optimum site location. Tasks were separated into four major elements: cost study, user survey, site selection, and press design/procurement specification
A new genus and species of Sphaeromatidae (Crustacea: Isopoda) with experiments and observations on its reproductive biology, interspecific interactions and color polymorphisms
The new genus, Paraleptosphaeroma, is distinguished from the morphologically similar genus Leptosphaeroma by the fusion of the pleonites, the shape of the peni, the attachment of appendix masculina, and the presence or the absence of an endopod on the first pleopod. The term cingula is introduced to refer to lateral margins fringed with setae and the distinction is drawn between setal and membranous forms of the cingula. Paraleptsphaeroma glynni (sp nov.) occurs on cobble in tidal pools and is associated with three sessile species, two bryozoans and a coralline alga. Experiments demonstrate the isopod to be a sequential hermaphrodite with a socially mediated sexual transformation. Brood mortality is very low. Observations of feeding and analysis of gut contents show anascan bryozoans to be the principal food sources of P. glynni. The principal color polymorphisms of juveniles are illustrated. The apparent concordance between these patterns and those produced by the boring activities of phoronids and barnacles is tested, with results suggesting that the color patterns are adaptations to concealment from fish predators. This interpretation is further supported by morphological evidence and experiments demonstrating the poor swimming ability of P. glynni
Low power, compact charge coupled device signal processing system
A variety of charged coupled devices (CCDs) for performing programmable correlation for preprocessing environmental sensor data preparatory to its transmission to the ground were developed. A total of two separate ICs were developed and a third was evaluated. The first IC was a CCD chirp z transform IC capable of performing a 32 point DFT at frequencies to 1 MHz. All on chip circuitry operated as designed with the exception of the limited dynamic range caused by a fixed pattern noise due to interactions between the digital and analog circuits. The second IC developed was a 64 stage CCD analog/analog correlator for performing time domain correlation. Multiplier errors were found to be less than 1 percent at designed signal levels and less than 0.3 percent at the measured smaller levels. A prototype IC for performing time domain correlation was also evaluated
Research Notes: Reaction to peanut mottle virus in plant introductions of Maturity Groups 00 through IV
The results of screening the soybean plant introductions in Maturity Groups II, III, and IV have been reported by Shipe et al. (1979) . The results of evaluating the earlier maturity groups are reported here. Plant introductions that became available after 1976 have not been screened
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