End or Ending may refer to:
In music, the conclusion is the ending of a composition and may take the form of a coda or outro.
Pieces using sonata form typically use the recapitulation to conclude a piece, providing closure through the repetition of thematic material from the exposition in the tonic key. In all musical forms other techniques include "altogether unexpected digressions just as a work is drawing to its close, followed by a return...to a consequently more emphatic confirmation of the structural relations implied in the body of the work."
For example:
In the mathematics of infinite graphs, an end of a graph represents, intuitively, a direction in which the graph extends to infinity. Ends may be formalized mathematically as equivalence classes of infinite paths, as havens describing strategies for pursuit-evasion games on the graph, or (in the case of locally finite graphs) as topological ends of topological spaces associated with the graph.
Ends of graphs may be used (via Cayley graphs) to define ends of finitely generated groups. Finitely generated infinite groups have one, two, or infinitely many ends, and the Stallings theorem about ends of groups provides a decomposition for groups with more than one end.
Ends of graphs were defined by Rudolf Halin (1964) in terms of equivalence classes of infinite paths. A ray in an infinite graph is a semi-infinite simple path; that is, it is an infinite sequence of vertices v0, v1, v2, ... in which each vertex appears at most once in the sequence and each two consecutive vertices in the sequence are the two endpoints of an edge in the graph. According to Halin's definition, two rays r0 and r1 are equivalent if there is another ray r2 (not necessarily different from either of the first two rays) that contains infinitely many of the vertices in each of r0 and r1. This is an equivalence relation: each ray is equivalent to itself, the definition is symmetric with regard to the ordering of the two rays, and it can be shown to be transitive. Therefore, it partitions the set of all rays into equivalence classes, and Halin defined an end as one of these equivalence classes.
An erg (also sand sea or dune sea, or sand sheet if it lacks dunes) is a broad, flat area of desert covered with wind-swept sand with little or no vegetative cover. The term takes its name from the Arabic word ʿarq (عرق), meaning "dune field". Strictly speaking, an erg is defined as a desert area that contains more than 125 square kilometres (48 sq mi) of aeolian or wind-blown sand and where sand covers more than 20% of the surface. Smaller areas are known as "dune fields". The largest hot desert in the world, the Sahara, covers 9 million square kilometres (3.5×10^6 sq mi) and contains several ergs, such as the Chech Erg (24°34′N 2°35′W / 24.57°N 2.59°W / 24.57; -2.59) and the Issaouane Erg (31°11′N 7°56′E / 31.18°N 7.93°E / 31.18; 7.93) in Algeria. Approximately 85% of all the Earth's mobile sand is found in ergs that are greater than 32,000 square kilometres (12,000 sq mi). Ergs are also found on other celestial bodies, such as Venus, Mars, and Saturn's moon Titan.
Erg was a vessel built and owned by Halifax Steamship Ltd. in 1915. She was used to ferry workers across the harbour to vessels under repair during the Second World War. Erg was sunk in the Halifax Harbour three times and is currently located in the Bedford Basin.
Erg was originally a steam tug called Sambro and was built by the Halifax Shipyard in 1915. She was one of the earliest steel vessels to be built in Halifax. Sambro was 55 feet long and almost 15 feet wide, with a depth of 7 feet and her maximum tonnage was 28. The tug was originally sunk during the Halifax Explosion of 1917. In 1927, Sambro was raised out of the harbour and was converted from steam to diesel, being given a 4 horsepower engine. With this change, the tug was given a new name and a new purpose. The vessel was renamed Erg and was used as a transport tug, ferrying workers and their equipment from the shipyard to vessels under repair.
Halifax Harbour was an extremely busy port during the Second World War. Because of this, navigational dangers increased with the congestion in the harbour. The Naval Service of Canada, which kept records of the activity in the harbour, advised that from 1940 to 1943, there were at least 12 vessels involved in accidents within Halifax Harbour. Vessels such as Camperdown, Claire Lilley and Nueva Indalucia ran aground, whereas others such as Otter, and Trongate caught fire and sank (or, in the case of Trongate, was made to sink as the flames were completely out of control). In 1940, Herbidean was sunk by the British ship Esmond; a forerunner to the fate of Erg.
An erg is a unit of energy.
Erg, or Ergs, may also refer to:
ERG, or ERGS, may stand for: