2 results match your criteria: "555 National Center[Affiliation]"

Preliminary investigation of submerged aquatic vegetation mapping using hyperspectral remote sensing.

Environ Monit Assess

May 2003

Landscape Ecology Branch, Environmental Sciences Division, U.S. Environmental Protection Agency, 12201 Sunrise Valley Drive, 555 National Center, Reston, VA 20192, USA.

The use of airborne hyperspectral remote sensing imagery for automated mapping of submerged aquatic vegetation (SAV) in the tidal Potomac River was investigated for near to real-time resource assessment and monitoring. Airborne hyperspectral imagery and field spectrometer measurements were obtained in October of 2000. A spectral library database containing selected ground-based and airborne sensor spectra was developed for use in image processing.

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A year-long investigation of air change rates in an occupied house was undertaken to establish the effects of temperature, wind velocity, use of exhaust fans, and window-opening behavior. Air change rates were calculated by periodically injecting a tracer gas (SF(6)) into the return air duct and measuring the concentration in 10 indoor locations sequentially every minute by a gas chromatograph equipped with an electron capture detector. Temperatures were also measured outdoors and in the 10 indoor locations.

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