1,055 research outputs found

    Satellite Capabilities Mapping - Utilizing Small Satellites

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    The cost and schedule advantages small satellites have over larger legacy systems have been studied, but there has been very little experimentation performed to determine whether small satellites can actually deliver the capabilities of larger spacecraft. To date, a desired operational capability has not been fully realized by a scalable satellite design. Advances in sensor technology have led to significant reductions in size, weight, and power (SWaP) presenting an opportunity to exploit the evolution of space operations by using small satellites to perform specific missions. This paper describes a methodology that maps a specific set of large space vehicle capabilities to CubeSats. The process examines the utility of advanced sensors. Space weather has been identified as an excellent mission area to exploit the potential of small satellites. Advances in micro-electronics have produced sensors with reduced SWaP, making them viable test subjects. Mapping capabilities to a single or constellation of small satellites, could provide solutions and affordable options to the adverse challenges facing space operations. The methodology developed here selects sensor of the National Polar-Orbiting Environmental Satellite System (NPOESS) Space Environmental Sensor Suite (SESS) and maps them to a CubeSat illustrating a small satellite can perform an operational mission

    Studies on the Role of Solar Ultraviolet Radiation in Natural Water Purification by Aquatic Ecosystems

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    The possibility that pollution might deplete the stratospheric ozone layer and intensify solar UV at the earth\u27s surface focuses attention on the role of solar UV in the various ecosystems at the earth\u27s surface. Previous studies suggested that solar UV might contribute to bacterial die off in wastewater and the studies reported here were directed toward elucidating the action of solar UV in natural waters. It has been assumed that solar UV action on aquatic ecosystems can be evaluated (using proper models) on the basis of the following four independently measurable quantities: I) the intensity of solar UV at the water surface, 2) the attenuation of the UV in the water column, 3) the position of the critical organisms in the water, and 4) the sensitivity of the individual organisms to solar UV exposure. These four factors have been investigated on a continuing basis and the results of measurements have been utilized along with special field and laboratory experiments to assess UV-B actions. Field work has focused on the succession of organisms, their locations in the water column, a,d under more controlled conditions, the killing of E. coli by natural sunlight. Laboratory work has included studies of UV-B lethality, its ability to stimulate positioning responses, and its depression of the photosynthetic activity of algae. Laboratory and field observations have been interpreted through models and our results are consistent with the hypothesis that solar UV is a significant agent for the aquatic microorganisms we have tested

    Sustaining and Realizing the Promise of Telemedicine

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    Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/140277/1/tmj.2012.0282.pd
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