Lightning is located by using the time of group arrival (TOGA) of the VLF (3–30 kHz) radiation from a lightning stroke. The dispersed waveform (“sferic”) of the lightning impulse is processed at each receiving site. The TOGA is determined relative to GPS at each site from the progression of phase versus frequency using the whole wave train. Unlike current VLF methods which require transmission ...

The variations of phase and amplitude of a subionospheric transmitted signal at frequency 19.8 kHz from North West Cape, Australia (latitude: 21.82◦S; longitude: 114.16◦E) measured at Kolkata (latitude: 22.56◦N, longitude: 88.5◦E) during the period of solar eclipse (partial, 91.1%) on July 22, 2009 will be presented in this paper. The variations in amplitude are quite significant than the usual...

two dimensional single frequency scalar vlf data modeling has been studied in this research. vlf method is one of the electromagnetic investigation methods. radio frequency waves are used for investigation of conductive deposits (paal, 1968). synthetic modeling and inversion of single frequency and multiple frequencies of vlf signals was done by oskooi (2004) for two dimensional simple structur...

Mitsis, Georgios D., Rong Zhang, Benjamin D. Levine, and Vasilis Z. Marmarelis. Cerebral hemodynamics during orthostatic stress assessed by nonlinear modeling. J Appl Physiol 101: 354–366, 2006. First published March 2, 2006; doi:10.1152/japplphysiol.00548.2005.—The effects of orthostatic stress, induced by lower body negative pressure (LBNP), on cerebral hemodynamics were examined in a nonline...

The effects of orthostatic stress, induced by lower body negative pressure (LBNP), on cerebral hemodynamics were examined in a nonlinear context. Spontaneous fluctuations of beat-to-beat mean arterial blood pressure (MABP) in the finger, mean cerebral blood flow velocity (MCBFV) in the middle cerebral artery, as well as breath-by-breath end-tidal CO2 concentration (P(ET(CO2))) were measured con...

[1] Lightning discharges radiate most of their electromagnetic energy in the very low frequency (VLF, 3–30 kHz) and extremely low frequency (ELF, 3–3000 Hz) bands and are, consequently, an effective tool for remotely sensing the nighttime ionospheric D region electron density profile. Using broadband lightning-generated VLF signals, we derived the night-to-night variations of the midlatitude io...

We assessed the convergent validity of commonly applied metrics of cerebral autoregulation (CA) to determine the extent to which the metrics can be used interchangeably. To examine between-subject relationships among low-frequency (LF; 0.07-0.2 Hz) and very-low-frequency (VLF; 0.02-0.07 Hz) transfer function coherence, phase, gain, and normalized gain, we performed retrospective transfer functi...