Horizon+Node

toc
 * Home * Search * Node * Horizon Node**


 * Horizon nodes** are nodes at depth zero, where a quiescence search is performed. The definition is taken from the papers of Ernst A. Heinz depth == 0 nodes . If the horizon node is an expected Cut-Node, confirmed by the evaluated standing pat score already greater or equal than beta, the horizon node is a leaf with the lower bound score of beta (fail-hard) or the stand pat score (fail-soft). Otherwise, winning captures (or checks) may either cause a beta-cutoff or raise alpha with an exact score at PV-Nodes. At expected All-Nodes with evaluated score (far) below alpha, if no tactical move is available, or due to Delta Pruning good enough to raise alpha, those leaves return alpha (fail-hard) as an upper bound. This may also appear, if this horizon node was not a leaf, since some captures were not pruned, but tried without raising alpha.

=Horizon Observatory=
 * [[image:800px-Hoheward-Panorama.jpg link="https://commons.wikimedia.org/wiki/File:Hoheward-Panorama.jpg"]] ||
 * [|Horizon Observatory] (left) and horizontal [|Sundial] with [|Obelisk] (right), [|Hoheward Spoil tip], The Industrial Heritage Trail 360–degree [|Panorama] Photo by [|Panofreak], April 12, 2009, [|Hoheward Spoil tip] in [|Herten], [|North Rhine-Westphalia], Germany, The Industrial Heritage Trail, view over the [|Ruhr area]. The observatory consists of a circular, flat surface of 88 m diameter, and a center forum lowered by 1.50 m with 35 m diameter with two arcs spanning [|meridian] and [|celestial equator]. The horizon observatory is a modern version of [|prehistoric] [|stone circles] and monuments such as [|Stonehenge]. If the observer is located exactly in the lowered center, the plateau of the tip spreads in all directions like an artificial horizon, and with the help of bearing points the [|sunrise] and [|sunset] at [|summer solstice], [|winter solstice] or [|equinox] can be observed, by means of further bearing points also [|moon] solstices and the [|precession] of [|Earth's axis] based on bearings of [|fixed stars]. The arcs divide the [|celestial sphere] in eastern and western half as well as in [|northern] and [|southern hemisphere] and therefore serve as a [|solar calendar] at day, and at night, with the help of a [|self-luminous] scale as a guide of the [|night sky], [|Halden im Ruhrgebiet] (German) ||

=See also=
 * Frontier Nodes
 * Horizon Effect
 * Leaf Node
 * Quiescent Node

=External Links= > Commissioned for the opening of [|Wales Millennium Centre], first performed at its opening on November 29, 2004 > media type="youtube" key="u3HTUzSnEbs" width="480"
 * Karl Jenkins - [|In These Stones Horizons Sing] (4th movement), [|YouTube] Video

=References= =What links here?= include page="Horizon Node" component="backlinks" limit="40"
 * Up one Level**