1 2 Abstract This paper presents new measurements of the magnetic field component of naturally–produced electromagnetic radiation in the ELF/VLF range. The measurements are compared to calculations based on modal propagation theory. The nocturnal spectrum below 5 kHz often contains a sharp increase in spectral level at the cutoff frequency of the first mode… (More)
Postimplantation as well as preimplantation pregnancy in prairie voles can be terminated by replacing the original stud male with an unfamiliar male. The pregnancy is disrupted by the ensuing male-induced estrus. Females spontaneously abort their litters, become receptive, and successfully breed again 4 or 5 days after introduction of the new male.
We consider the detection in the presence of 1=f noise of a known transient signal of unknown amplitude, scale and delay. We introduce a generalized likelihood ratio test (GLRT) method based on pattern matching in the undec-imated discrete wavelet transform (UDWT) domain. In many cases, the computational complexity of the detector can be reduced with… (More)
Using a unified approach, expressions are derived for the various pole positions and other dipole parameters for the centered and eccentric dipole models of the earth's magnetic field. The pole positions and other Parameters are then calculated using the 1945-i985 International Geomagnetic Reference Field Gauss coefficients and coefficients from models of… (More)
We address the problem of identifying and removing man-made transients from geomagnetic time series acquired with an array of magnetometers. We model the tran-sients as scaling functions of unknown scales, amplitudes, and delays. We then use an undecimated discrete wavelet transform to identify the transients in the presence of the natural 1=f geomagnetic… (More)
Measurements of 82 Hz radio signals from a Russian ELF transmitter located on the Kola Peninsula are described. The measurements were made at several locations around the world, including Dunedin, New Zealand, and Arrival Heights, Antarctica, which are close to the antipodal point for the transmitter. This is the first time man-made ELF signals have been… (More)
The specific long-term goal of this project is to provide the Navy with greatly improved information about the characteristics of both natural and man-made radio noise and signals in the ELF/VLF bands (frequencies in the range 10 Hz to 32 kHz), with the object of improving the Navy's ELF/VLF radio communications. SCIENTIFIC OBJECTIVES The project has two… (More)