Low frequency sub-surface radio is used for communications with miners and cavers. The signal attenuation is dependent on frequency and on the electrical conductivity of the ground. In addition, the optimum frequency for communications is dependent on depth below the surface; and on the degree of noise and cochannel interference. An adaptive communications system makes use of a channel-sounding...

Previous research has shown that frequency-specific estimates of auditory time constants for recovery from short-term adaptation can be made using a fixed-probe forward-masking procedure (Nelson & Freyman, 1987) if the masker and the probe stimuli are at the same frequency. This study examines the validity of time-constant estimates for off-frequency forward-masking conditions in which the mask...

We derive closed-form expressions for the Jacobian of matrix exponential function both diagonalizable and defective matrices. The results are applied to two cases interest in macroeconometrics : a continuous-time macro model parameterization rotation matrices governing impulse response functions structural vector autoregressions .

Abstract We present Swift/Ultraviolet Optical Telescope (UVOT) integrated light photometry of the Spitzer Infrared Nearby Galaxies Survey (SINGS) and Key Insights on Galaxies: A Far-Infrared with Herschel (KINGFISH) samples nearby galaxies. Combining Swift/UVOT data archival photometry, we investigate a variety dust attenuation curves derived using MCSED , flexible spectral energy distribution ...