Known for hot temperatures, Southern California and the rest of the Southwest United States are undergoing a cold snap that has set records in many areas throughout the region.
Periodogram is the spectrum of a set of time signal usually obtained by fast Fourier transform (FFT). It usually shows frequency as x-axis, and magnit... This page may be out of date.
A seismogram being recorded by a seismograph at Weston Observatory in Massachusetts A seismogram is a graph output by a seismograph. It is a record of the ground motion at a measuring station as a function of time. Seismograms typically record motions in three cartesian axes, with the z axis perpendicular to the Earth's surface and the x- and y- axes parallel to the surface. The energy measured in a seismogram may result from an earthquake or from some other source, such as an explosion. Seismograms can record lots of things, and record many little waves, called microseisms. Th