2 Matching Results

Search Results

Advanced search parameters have been applied.
in subjects: "47 Other Instrumentation"  
Results: 1 - 2
open access

Stability of modulation transfer function calibration of surface profilometers using binary pseudo-random gratings and arrays with nonideal groove shapes

Description: The major problem of measurement of a power spectral density (PSD) distribution of surface heights with surface profilometers arises due to the unknown Modulation Transfer Function (MTF) of the instruments, which tends to distort the PSD at higher spatial frequencies. The special mathematical properties of binary pseudo-random patterns make them an ideal basis for developing MTF calibration test surfaces. Two-dimensional binary pseudo-random arrays (BPRAs) have been fabricated and used for the … more
Date: March 31, 2010
Creator: Barber, Samuel K.; Anderson, Erik H.; Cambie, Rossana; Marchesini, Stefano; McKinney, Wayne R.; Takacs, Peter Z. et al.
Partner: UNT Libraries Government Documents Department
open access

Acoustic and Seismic Modalities for Unattended Ground Sensors

Description: In this paper, we have presented the relative advantages and complementary aspects of acoustic and seismic ground sensors. A detailed description of both acoustic and seismic ground sensing methods has been provided. Acoustic and seismic phenomenology including source mechanisms, propagation paths, attenuation, and sensing have been discussed in detail. The effects of seismo-acoustic and acousto-seismic interactions as well as recommendations for minimizing seismic/acoustic cross talk have been… more
Date: March 31, 1999
Creator: Elbring, G.J.; Ladd, M.D.; McDonald, T.S. & Sleefe, G.E.
Partner: UNT Libraries Government Documents Department
Back to Top of Screen