QuadricIn mathematics, a quadric or quadric surface (quadric hypersurface in higher dimensions), is a generalization of conic sections (ellipses, parabolas, and hyperbolas). It is a hypersurface (of dimension D) in a (D + 1)-dimensional space, and it is defined as the zero set of an irreducible polynomial of degree two in D + 1 variables; for example, D = 1 in the case of conic sections. When the defining polynomial is not absolutely irreducible, the zero set is generally not considered a quadric, although it is often called a degenerate quadric or a reducible quadric.
Anna SuiAnna Sui (; born August 4, 1964) is an American fashion designer. She was named one of the "Top 5 Fashion Icons of the Decade", and in 2009 earned the Geoffrey Beene Lifetime Achievement Award from the Council of Fashion Designers of America (CFDA), joining the ranks of Yves Saint Laurent, Giorgio Armani, Ralph Lauren, and Diane von Furstenberg. Her brand categories include several fashion lines, footwear, cosmetics, fragrances, eyewear, jewelry, accessories, home goods and a gifts line.
.ch.ch is the country code top-level domain (ccTLD) for Switzerland in the Domain Name System of the Internet. Made available in 1987, only two years after .com, it is administered by SWITCH Information Technology Services. The domain ch, as with other ccTLDs, is based on the ISO 3166-2 code for Switzerland derived from Confoederatio Helvetica (Helvetic Confederation), the Latin name for the country, which was used because of its neutrality with regard to the four official languages of Switzerland.
Anna KomneneAnna Komnene (Ánna Komnēnḗ; 1 December 1083 – 1153), commonly Latinized as Anna Comnena, was a Byzantine princess and author of the Alexiad, an account of the reign of her father, the Byzantine emperor, Alexios I Komnenos. The Alexiad is the most important primary source of Byzantine history of the late 11th and early 12th centuries. Although she is best known as the author of the Alexiad, Anna played an important part in the politics of the time and attempted to depose her brother, John II Komnenos, as emperor and seize the throne herself.
FC VSS KošiceFC VSS Košice, formerly 1. FC Košice, was a Slovak football club based in Košice which played in the Slovak 2. Liga during the 2016–17 season. The club officially ceased operations on 27 July 2017. The club, founded in 1903, has won the Slovak League twice, the Slovak Cup five times and the Czechoslovak Cup once. The most successful eras of the club were in the 1970s and 1990s which they spent mostly in the top tier of Czechoslovak and Slovak Football. Two of the UEFA Euro 1976 champions namely Dušan Galis and Jaroslav Pollák played for Košice.
20222022 saw the removal of nearly all COVID-19 restrictions and the reopening of international borders in most countries, and the global rollout of COVID-19 vaccines continued. The global economic recovery from the pandemic continued, though many countries experienced an ongoing inflation surge; in response, many central banks raised their interest rates to landmark levels. The world population reached eight billion people in 2022, though the year also witnessed numerous natural disasters, including two devastating Atlantic hurricanes (Fiona and Ian), and the most powerful volcano eruption of the century so far.
RAF JurbyRoyal Air Force Station Jurby or more simply RAF Jurby is a former Royal Air Force station built in the north west of the Isle of Man. It was opened in 1939 on of land acquired by the Air Ministry in 1937, under the control of No. 29 Group, RAF. During the Second World War the station was used for training as No. 5 Armament Training Station, No. 5 Air Observer School, No. 5 Bombing & Gunnery School and the No. 5 Air Navigation & Bombing School. In addition RAF Jurby also played host to a variety of operational squadrons.
2008–09 Pittsburgh Penguins seasonThe 2008–09 Pittsburgh Penguins season was the 42nd season of Pittsburgh Penguins in the National Hockey League (NHL). The regular season began with two games against the Ottawa Senators in Stockholm, Sweden on October 4 and October 5, 2008. On February 15, the team had a record of 27–25–5 and was five points out of playoff position. The organization fired head coach Michel Therrien and replaced him with Dan Bylsma, head coach of the organization's American Hockey League affiliate in Wilkes-Barre.
Anna of RussiaAnna Ioannovna (Анна Иоанновна; - ), also russified as Anna Ivanovna and sometimes anglicized as Anne, served as regent of the duchy of Courland from 1711 until 1730 and then ruled as Empress of Russia from 1730 to 1740. Much of her administration was defined or heavily influenced by actions set in motion by her uncle, Peter the Great ( 1682 - 1725), such as the lavish building projects in St. Petersburg, funding the Russian Academy of Science, and measures which generally favored the nobility, such as the repeal of a primogeniture law in 1730.
Tangent coneIn geometry, the tangent cone is a generalization of the notion of the tangent space to a manifold to the case of certain spaces with singularities. In nonlinear analysis, there are many definitions for a tangent cone, including the adjacent cone, Bouligand's contingent cone, and the Clarke tangent cone. These three cones coincide for a convex set, but they can differ on more general sets. Let be a nonempty closed subset of the Banach space .
Tangent spaceIn mathematics, the tangent space of a manifold is a generalization of to curves in two-dimensional space and to surfaces in three-dimensional space in higher dimensions. In the context of physics the tangent space to a manifold at a point can be viewed as the space of possible velocities for a particle moving on the manifold. In differential geometry, one can attach to every point of a differentiable manifold a tangent space—a real vector space that intuitively contains the possible directions in which one can tangentially pass through .
