Numerical stabilityIn the mathematical subfield of numerical analysis, numerical stability is a generally desirable property of numerical algorithms. The precise definition of stability depends on the context. One is numerical linear algebra and the other is algorithms for solving ordinary and partial differential equations by discrete approximation. In numerical linear algebra, the principal concern is instabilities caused by proximity to singularities of various kinds, such as very small or nearly colliding eigenvalues.
Arbitrary-precision arithmeticIn computer science, arbitrary-precision arithmetic, also called bignum arithmetic, multiple-precision arithmetic, or sometimes infinite-precision arithmetic, indicates that calculations are performed on numbers whose digits of precision are limited only by the available memory of the host system. This contrasts with the faster fixed-precision arithmetic found in most arithmetic logic unit (ALU) hardware, which typically offers between 8 and 64 bits of precision.
Material derivativeIn continuum mechanics, the material derivative describes the time rate of change of some physical quantity (like heat or momentum) of a material element that is subjected to a space-and-time-dependent macroscopic velocity field. The material derivative can serve as a link between Eulerian and Lagrangian descriptions of continuum deformation. For example, in fluid dynamics, the velocity field is the flow velocity, and the quantity of interest might be the temperature of the fluid.
NitroxNitrox refers to any gas mixture composed (excepting trace gases) of nitrogen and oxygen. This includes atmospheric air, which is approximately 78% nitrogen, 21% oxygen, and 1% other gases, primarily argon. In the usual application, underwater diving, nitrox is normally distinguished from air and handled differently.
South Sea CompanyThe South Sea Company (officially: The Governor and Company of the merchants of Great Britain, trading to the South Seas and other parts of America, and for the encouragement of the Fishery) was a British joint-stock company founded in January 1711, created as a public-private partnership to consolidate and reduce the cost of the national debt. To generate income, in 1713 the company was granted a monopoly (the Asiento de Negros) to supply African slaves to the islands in the "South Seas" and South America.
Railway ManiaRailway Mania was an instance of a stock market bubble in the United Kingdom of Great Britain and Ireland in the 1840s. It followed a common pattern: as the price of railway shares increased, speculators invested more money, which further increased the price of railway shares, until the share price collapsed. The mania reached its zenith in 1846, when 263 Acts of Parliament for setting up new railway companies were passed, with the proposed routes totalling .