Repository files navigation

This is a collection of hacks I created usingPyNomo. Pynomo is also now on github atits author's repository,https://github.com/lefakkomies/pynomo.

The purpose is to provide a simple, usable set of nomographs thatsearch planners and debriefers can use to estimate Probability of Detection(POD) or the effort required to achieve a given POD, without having to pullout a computer and spreadsheet program to do so.

In order to generate the nomographs from the scripts (or hack on them), youmust first install PyNomo and all of its dependencies according tothe directions on its web site. Once PyNomo is installed properly,you can just run these scripts to produce the nomographs. The scriptsproduce PDFs of the nomographs for viewing in any PDF viewer orincorporation into other documents.

The repository contains PDF versions of the nomographs as generated by thepython scripts, so you don't have to unless you want to hack on 'em.

The two nomographs that are intended to be used arePOD_from_W_v_t_simplified.pdf and POD_from_W_L_N.pdf. The others areall just toys I created while learning PyNomo and building these two.

POD_from_W_v_t_simplified.pdf is intended for planning purposes, andinstructions for using it are in "PlanningNomograph_Instructions.odt",a LibreOffice document. It can be used to estimate the searchereffort (in "searcher-hours") required to achieve a given POD, knowingeither the effective sweep width or the measured average range ofdetection, the searcher speed and region area and desired POD.Alternatively, it can be used to determine the attainable POD using agiven level of effort (in searcher-hours).

Conversion between range of detection and sweep width makes use of theapproximate relations described inUse of the Visual Range ofDetection to Estimate Effective Sweep Widths for Land Search andRescue Based on 10 Detection Experiments in NorthAmerica.

The second nomograph, POD_from_W_L_N.pdf, is for debriefing purposes.It allows the debriefer to compute the POD of a completed search usingthe measured average range of detection (or alternatively thetabulated effective sweep width), the total track length of onesearcher in the team (as measured by GPS), the number of searchers onthe team, and the area searched. Instructions for using it are in"DebriefNomograph_Instructions.odt" (also a LibreOffice document).

PDF versions of both instruction sheets are also present in therepository, for those who cannot read LibreOffice documents.

These nomographs were created first as a little joke I was going topresent to a class on search theory at the 2015 New Mexico search andrescue conference, ESCAPE, showing how search planners of the 1940smight have computed the quantities in question. Then it occurred tome that the nomograph would actually be useful even to search plannersin the 21st century. Effective use of these nomographs does requirefamiliarity with search theory and its application. I drafted a tinyweb page with some useful papers and books to read if you'reinterested in this subject. It's athttp://pages.swcp.com/~russo/searchtheoryrefs.html.