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The voltages induced by nearby lightning strikes are a major cause of outages in power distribution systems. We compute such voltages taking into account the effects of the dart leaders that precede subsequent return strokes in both natural and rocket-trig ...
We report three RXTE/PCA observations of the low-mass X-ray binary 4U 0614+09. They show strong (similar to 30% rms) band-limited noise with a cutoff frequency varying between 0.7 and 15 Hz in correlation with the X-ray flux, f(x). We observe two nonsimult ...
We observed the low-mass X-ray binary and Z source GX 17+2 with the Rossi X-Ray Timing Explorer during 1997 February 6-8, April 1-4, and July 26-27. The X-ray color-color diagram shows a clear Z track. Two simultaneous kHz quasi-periodic oscillations (QPOs ...
During observations with the Rossi X-Ray Timing Explorer from 1997 June 31 to July 3 we discovered two simultaneous kHz quasi-periodic oscillations (QPOs) near 500 and 860 Hz in the low-mass X-ray binary and Z source Cygnus X-2. In the X-ray color-color di ...
The class of second-order curvilinear gratings consists of all the curvilinear gratings that are obtained by second-order spatial transformations of periodic gratings. It includes, for example, circular, elliptic, and hyperbolic gratings as well as circula ...
This paper highlights, both analytically and by simulations, some interesting phenomena regarding the behavior of ensemble-average learning curves of adaptive filters that may have gone unnoticed. Among other results, the paper shows that even ensemble-ave ...
Researchers working on the problem of the coupling of lightning electromagnetic fields to overhead lines have suggested that, if the formulation of the coupling problem given by Agrawal et al. is adopted, only the horizontal component of the electric field ...
A digital lock-in amplifier has been used to perform V-I time series acquisition when transport currents with amplitude above Ic are driven through Bi-2223 tapes. The current waveform is triangular, sinusoidal or with arbitrary shape, and is applied for se ...
Using a first-principles approach, we study the vibrational properties of vitreous SiO2 which are measured in neutron-scattering experiments. We adopt a model structure consisting of corner-sharing tetrahedra, which was previously generated using first-pri ...
The digital transient torque measuring device presented in this paper is able to make a "real time" calculation in steady-state and transient conditions of the electromagnetic torque or force of an extremely wide range of ac electrical machines supplied wi ...
