Search results
Results from the WOW.Com Content Network
The most prominent examples of covering problems are the set cover problem, which is equivalent to the hitting set problem, and its special cases, the vertex cover problem and the edge cover problem. Covering problems allow the covering primitives to overlap; the process of covering something with non-overlapping primitives is called decomposition.
Pages in category "Covering problems" The following 10 pages are in this category, out of 10 total. This list may not reflect recent changes. * Covering problems; A.
In the fractional set cover problem, it is allowed to select fractions of sets, rather than entire sets. A fractional set cover is an assignment of a fraction (a number in [0,1]) to each set in , such that for each element x in the universe, the sum of fractions of sets that contain x is at least 1. The goal is to find a fractional set cover in ...
Now in its 60th year, the list sounds the alarm about animals and plants at risk of extinction, but it also high List of threatened species grows by 1,000, but conservation efforts bring hope for ...
Unsolved problems relating to the behaviour of animals include: Homing. A satisfactory explanation for the neurobiological mechanisms that allow homing in animals has yet to be found. Flocking (behavior). How flocks of birds and bats coordinate their movements so quickly is not fully understood.
The word skin originally only referred to dressed and tanned animal hide and the usual word for human skin was hide. Skin is a borrowing from Old Norse skinn "animal hide, fur", ultimately from the Proto-Indo-European root *sek-, meaning "to cut" (probably a reference to the fact that in those times animal hide was commonly cut off to be used as garment).
The Red List of 2012 was released 19 July 2012 at Rio+20 Earth Summit; [17] nearly 2,000 species were added, [18] with 4 species to the extinct list, 2 to the rediscovered list. [19] The IUCN assessed a total of 63,837 species which revealed 19,817 are threatened with extinction.
An echinoderm (/ ɪ ˈ k aɪ n ə ˌ d ɜːr m, ˈ ɛ k ə-/) [2] is any animal of the phylum Echinodermata (/ ɪ ˌ k aɪ n oʊ ˈ d ɜːr m ə t ə /), which includes starfish, brittle stars, sea urchins, sand dollars and sea cucumbers, as well as the sessile sea lilies or "stone lilies". [3]