Logarithmic number system Logarithmic number system A logarithmic number system (LNS) is an arithmetic system used for representing real numbers in computer and digital hardware, especially for digital signal processing. In an LNS, a number, formula_1, is represented by the logarithm, formula_2, of its absolute value as follows: where formula_4 is a bit denoting the sign of formula_1 (formula_6 if formula_7 and formula_8 if formula_9). The number formula_2 is represented by a binary word which usually is in the two's complement format. An LNS can be considered as a floating-point number with the significand being always equal to 1 and a non-integer exponent.
Contact binary of years, the common envelope is a dynamically unstable phase in binary evolution that either expels the stellar envelope or merges the binary in a timescale of months to years. Contact binary In astronomy, a contact binary is a binary star system whose component stars are so close that they touch each other or have merged to share their gaseous envelopes. A binary system whose stars share an envelope may also be called an overcontact binary. Almost all known contact binary systems are eclipsing binaries; eclipsing contact binaries are known as W Ursae Majoris variables, after their type star, W