2,164 research outputs found

    Next Generation Orientation Systems: Cell phone tours at the Undergraduate and Main Libraries at the University of Illinois at Urbana-Champaign

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    This poster describes the implementation of a self guided cell-phone tour within the Undergraduate and Main Libraries at the University of Illinois at Urbana-Champaign. The most compelling use of mobile technology features immediacy and personalization as the primary goals. Signage throughout the libraries provoke patron curiosity with such questions as Where am I? and What has the Career Cluster done for me lately? A call to a local phone number provides patrons with the answer, along with an invitation to listen to any of the fifteen pre-recorded messages describing library services, popular resources, or building history and art. As an alternative to the traditional tour and library orientation session, this cell phone tour responds to trends in, and preferences for mobile technology while engaging a broader audience. This poster discusses the implementation and assessment of the cell phone tour, and provides strategies for libraries seeking to incorporate similar technology

    Risk Premia in Commodity Price Forecasts and their Impact on Valuation

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    Propulsion Selection for 85kft Remotely Piloted Atmospheric Science Aircraft

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    This paper describes how a 3 stage turbocharged gasoline engine was selected to power NASA's atmospheric science unmanned aircraft now under development. The airplane, whose purpose is to fly sampling instruments through targeted regions of the upper atmosphere at the exact location and time (season, time of day) where the most interesting chemistry is taking place, must have a round trip range exceeding 1000 km, carry a payload of about 500 lb to altitudes exceeding 80 kft over the site, and be able to remain above that altitude for at least 30 minutes before returning to base. This is a subsonic aircraft (the aerodynamic heating and shock associated with supersonic flight could easily destroy the chemical species that are being sampled) and it must be constructed so it will operate out of small airfields at primitive remote sites worldwide, under varying climate and weather conditions. Finally it must be low cost, since less than $50 M is available for its development. These requirements put severe constraints on the aircraft design (for example, wing loading in the vicinity of 10 psf) and have in turn limited the propulsion choices to already-existing hardware, or limited adaptations of existing hardware. The only candidate that could emerge under these circumstances was a propeller driven aircraft powered by spark ignited (SI) gasoline engines, whose intake pressurization is accomplished by multiple stages of turbo-charging and intercooling. Fortunately the turbocharged SI powerplant, owing to its rich automotive heritage and earlier intensive aero powerplant development during WWII, enjoys in addition to its potentially low development costs some subtle physical advantages (arising from its near-stochiometric combustion) that may make it smaller and lighter than either a turbine engine or a diesel for these altitudes. Just as fortunately, the NASA/industry team developing this aircraft includes the same people who built multi-stage turbocharged SI powerplants for unmanned military spyplanes in the early 1980's. Now adapting hardware developed for reconaissance at 65-70 kft to the interests of atmospheric science at 80-90 kft, their efforts should yield an aero powerplant that pushes the altitude limits of subsonic air breathing propulsion
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