Variable stars are those that change brightness. Their variability may be due to geometric processes such as rotation, or eclipse by a companion star, or physical processes such as vibration, ﬂares, or cataclysmic explosions. In each case, variable stars provide unique information about the properties of stars, and the processes that go on within them.
Our knowledge of mass transfer processes has been extended and applied to various fields of science and engineering including industrial and manufacturing processes in recent years. Since mass transfer is a primordial phenomenon, it plays a key role in the scientific researches and fields of mechanical, energy, environmental, materials, bio, and chemical engineering. In this book, energetic authors provide present advances in scientific findings and technologies, and develop new theoretical models concerning mass transfer....
Traditionally astrophysics has concerned itself with minimum time-scales measured
in hours rather than seconds. This was understandable as the available recording
media were slow; e.g. chart recorders and photographic plates. In the 1950s, 60s
and 70s wavebands away from the optical were developed; from ground based
radio studies to space and balloon borne high energy work. In contrast to optical
wavelengths instrumentation in these (high and low energy) regimes was capable
of time resolutions of less than a second....