Anemometer Anemometer An anemometer is a device used for measuring wind speed, and is also a common weather station instrument. The term is derived from the Greek word "anemos", which means wind, and is used to describe any wind speed instrument used in meteorology. The first known description of an anemometer was given by Leon Battista Alberti in 1450. The anemometer has changed little since its development in the 15th century. Leon Battista Alberti (1404–1472) is said to have invented the first mechanical anemometer around 1450. In following centuries, numerous others, including Robert Hooke (1635–1703), developed their own versions, with some
Convergence in measure formula_14, "μ" be Lebesgue measure, and "f" the constant function with value zero. (The first five terms of which are formula_19) converges to "0" globally in measure; but for no "x" does "f(x)" converge to zero. Hence "(f)" fails to converge to "f" almost everywhere. There is a topology, called the topology of (local) convergence in measure, on the collection of measurable functions from "X" such that local convergence in measure corresponds to convergence on that topology. This topology is defined by the family of pseudometrics where In general, one may restrict oneself to some subfamily of sets "F" (instead