Altitude

Altitude or height (sometimes known as depth) is defined based on the context in which it is used (aviation, geometry, geographical survey, sport, and many more). As a general definition, altitude is a distance measurement, usually in the vertical or "up" direction, between a reference datum and a point or object. The reference datum also often varies according to the context. Although the term altitude is commonly used to mean the height above sea level of a location, in geography the term elevation is often preferred for this usage.

Vertical distance measurements in the "down" direction are commonly referred to as depth.

Altitude in aviation

In aviation, the term altitude can have several meanings, and is always qualified by either explicitly adding a modifier (e.g. "true altitude"), or implicitly through the context of the communication. Parties exchanging altitude information must be clear which definition is being used.

Aviation altitude is measured using either mean sea level (MSL) or local ground level (above ground level, or AGL) as the reference datum.

Altitude (film)

Altitude is a Canadian horror, television and "direct-to-video" film directed by Canadian comic book writer and artist Kaare Andrews.Anchor Bay Entertainment is set to distribute the film in North America, U.K., Australia, and New Zealand.

The trailer for Altitude premiered at the 2010 San Diego Comic Con.

Plot

In the prologue, the mother of Sara (Jessica Lowndes) is transporting a family of three (two parents and their son) in a small aircraft. The child is extremely nervous and starts hyperventilating. Wondering why he is so afraid, the parents suddenly see an out-of-control aircraft that crashes into them, and everyone plummets to the ground.

Years later, Sara, who has recently received her pilot's license, is planning to fly to a concert with her friends: her boyfriend Bruce Parker (Landon Liboiron), her cousin Cory (Ryan Donowho), her best friend Mel (Julianna Guill) and Mel's boyfriend Sal (Jake Weary). While in the air, Bruce's nerves draw ridicule from the others and Sara invites him to take the controls. They hit some turbulence and Bruce loses control, taking them into a steep climb.

Altitude (triangle)

In geometry, an altitude of a triangle is a line segment through a vertex and perpendicular to (i.e. forming a right angle with) a line containing the base (the opposite side of the triangle). This line containing the opposite side is called the extended base of the altitude. The intersection between the extended base and the altitude is called the foot of the altitude. The length of the altitude, often simply called the altitude, is the distance between the extended base and the vertex. The process of drawing the altitude from the vertex to the foot is known as dropping the altitude of that vertex. It is a special case of orthogonal projection.

Altitudes can be used to compute the area of a triangle: one half of the product of an altitude's length and its base's length equals the triangle's area. Thus the longest altitude is perpendicular to the shortest side of the triangle. The altitudes are also related to the sides of the triangle through the trigonometric functions.

Tangle (mathematics)

In mathematics, the word tangle usually refers to one of two related concepts:

In link theory, a tangle is an embedding of n arcs and m circles into – the difference from the previous definition is that it includes circles as well as arcs, and partitions the boundary into two (isomorphic) pieces, which is algebraically more convenient – it allows one to add tangles by stacking them, for instance.

(A quite different use of 'tangle' appears in Graph minors X. Obstructions to tree-decomposition by N. Robertson and P. D. Seymour, J. Combinatorial Theory B 59 (1991) 153--190, who used it to describe separation in graphs. This usage has been extended to matroids.)

The balance of this article discusses Conway's sense of tangles; for the link theory sense, see that article.

Two n-tangles are considered equivalent if there is an ambient isotopy of one tangle to the other keeping the boundary of the 3-ball fixed. Tangle theory can be considered analogous to knot theory except instead of closed loops we use strings whose ends are nailed down. See also braid theory.

Tangle (series 3)

The third series of Tangle, an Australian drama television series, was confirmed in December 2010, and production began in June 2011 and ended in August. Series three will contain six episodes, and is written by Fiona Seres and Tony McNamara, and directed by Emma Freeman and Michael James Rowland.

Cast

Episodes

References

Tangle (TV series)

Tangle is an Australian drama series for the Showcase subscription television channel. It focuses on the tangled lives of two generations of two families. Tangle is filmed in Melbourne and first screened on 1 October 2009. It is written by Fiona Seres, Tony McNamara and Judi McCrossin, and directed by Jessica Hobbs, Matthew Saville and Stuart McDonald. There have so far been three seasons.

Plot

Season 1

Tangle revolves around the intertwined lives of the Kovac and Williams families and their network of friends and extended family. Nat Manning (Kat Stewart) returned to her home town of Melbourne after ten years in England on the minor celebrity circuit. She created ripples and then waves in the lives of two clans already struggling under the weight of their myriad secrets. Ally (Justine Clarke) is the devoted wife of builder Vince (Ben Mendelsohn), mother of Romeo and Gigi (Lincoln Younes and Eva Lazarro), who is happy to have her sister Nat back. Politician Tim (Joel Tobeck) had an affair 15 years ago with Nat, and as a result, Nat became pregnant. Tim and his wife Christine (Catherine McClements) patched up their marriage and fought hard for custody of the child, Max (Blake Davis). Divorcee Em is having an affair with married man Vince and doctor Gabriel (Matt Day) has a secret lust for married Ally.