efficient machines
41Doubly fed electric machine — Doubly fed electric machines are electric motors or electric generators that have windings on both stationary and rotating parts, where both windings transfer significant power between shaft and electrical system. Doubly fed machines are useful… …
42Fusion power — The Sun is a natural fusion reactor. Fusion power is the power generated by nuclear fusion processes. In fusion reactions two light atomic nuclei fuse together to form a heavier nucleus (in contrast with fission power). In doing so they release a …
43Europe, history of — Introduction history of European peoples and cultures from prehistoric times to the present. Europe is a more ambiguous term than most geographic expressions. Its etymology is doubtful, as is the physical extent of the area it designates.… …
44Water wheel — This article is about the machine for converting energy of flowing or falling water. For paddle wheels used to propel watercraft, see paddle wheel ship. For wheels used solely to lift water, see Noria. For factories or industries driven by water… …
45Algorithm — Flow chart of an algorithm (Euclid s algorithm) for calculating the greatest common divisor (g.c.d.) of two numbers a and b in locations named A and B. The algorithm proceeds by successive subtractions in two loops: IF the test B ≤ A yields yes… …
46commercial fishing — Introduction the taking of fish and other seafood and resources from oceans, rivers, and lakes for the purpose of marketing them. Fishing is one of the oldest employments of humankind. Ancient heaps of discarded mollusk shells (shell… …
47steel — steellike, adj. /steel/, n. 1. any of various modified forms of iron, artificially produced, having a carbon content less than that of pig iron and more than that of wrought iron, and having qualities of hardness, elasticity, and strength varying …
48clothing and footwear industry — Introduction also called apparel and allied industries, garment industries, or soft goods industries, factories and mills producing outerwear, underwear, headwear, footwear, belts, purses, luggage, gloves, scarfs, ties, and household… …
49Virtual machine — A virtual machine (VM) is a completely isolated guest operating system installation within a normal host operating system .[1] Modern virtual machines are implemented with either software emulation or hardware virtualization or (in the most… …
50Zilog Z80 — One of the first Z80 microprocessors manufactured; the date stamp is from June 1976. Produced 1976 Common manufacturer(s) Zilog …
