Lava is the extrusive equivalent of magma. Magma (from Greek Î¼Î¬Î³Î¼Î±, thick unguent) is a mixture of molten or semi-molten rock, volatiles and solids that is found beneath the surface of the Earth, and is expected to exist on other terrestrial planets. Besides molten rock, magma may also contain suspended crystals, dissolved gas and sometimes gas bubbles.
Mean opinion score. Mean opinion score (MOS) is a measure used in the domain of Quality of Experience and telecommunications engineering, representing overall quality of a stimulus or system. It is the arithmetic mean over all individual âvalues on a predefined scale that a subject assigns to his opinion of the performance of a system qualityâ.
STC stands for Sound Transmission Class. Basically, STC ratings are an established way to average how much sound is stopped by something. STC ratings are used for windows, doors, walls and most building materials. For windows, STC ratings range from 18 to 38.STC ratings are the ONLY way to accurately compare various noise reduction products.n STC rating is an instrument measurement of how much noise is stopped. The STC ratings allow accurate âapple to appleâ comparisons. The STC rating is the average amount of noise stopped at 18 different frequencies, measured in decibels.