
Accession Number : ADA112481
Title : A Result in the Theory of Spiral Search.
Descriptive Note : Professional paper,
Corporate Author : CENTER FOR NAVAL ANALYSES ALEXANDRIA VA OPERATIONS EVALUATION GROUP
Personal Author(s) : Nunn,Walter R
PDF Url : ADA112481
Report Date : Mar 1980
Pagination or Media Count : 16
Abstract : This note presents a result in the theory of spiral search which does not seem to be available in the literature in spite of its straightforward derivation and obvious applicability in certain types of 'real life' search problems. The result gives the probability of detection as a function of time for a class of prior distributions of searchobject, i.e. target, position centered at the origin of the x,y plane. We restrict attention to a spiraltype search in which the searcher covers the AOU(area of uncertainty) in concentric rings, moving out from the center. In the common case that the prior density is circular normal, the time to detection is seen to be approximately exponentially distributed. This is a somewhat counterintuitive result in that the detection rate is constant, since it would appear that detection rate must decrease with time as the searcher moves from high probability areas to low probability areas.
Descriptors : *Target detection, *Searching, *Flight paths, Position finding, Probability, Time, Distribution, Rings, Circles, Flight speed indicators, Variable coordinates
Subject Categories : Air Navigation and Guidance
Distribution Statement : APPROVED FOR PUBLIC RELEASE