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A Method for Determining Effective Sweep Widths for Land Searches. Procedures for Conducting Detection Experiments

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For the first time, a standard, simple, practical, and low-cost method for conducting detection experiments for ground searches was successfully developed and demonstrated. This included a simple method for reducing the data obtained in such experiments that requires only minimal computation and the construction of a simple graph. Two types of objects were useda fluorescent orange glove and a black balloon-filled 55-gallon plastic garbage bag. Twelve gloves and nine garbage bags were placed randomly along either side of a 2.25 kilometer track in a wooded area. Thirty-two searchers participated in the demonstration, providing 384 detection opportunities for gloves and 288 detection opportunities for garbage bags. Preliminary visual effective sweep width a.k.a. detectability index estimates were obtained for each object type for the type of environment in which the demonstration was conducted. Land search and rescue SAR organizations will now be able to conduct detection experiments in their own respective areas of responsibility using their own resources to produce effective sweep width values for their own use and the use of others in similar search situations. This work constitutes a major breakthrough for improving land search planning and evaluation methods by replacing subjective estimates for probability of detection POD with objective ones that are more reliable, repeatable, and accurate than current subjective techniques. This work will also make it possible to bring known and proven methods for the optimal allocation of search resources to each situation that requires areas to be searched, leading to multiple benefits. These benefits include finding survivors sooner on average and thereby saving more lives, reducing risks to searchers through reduced search times, reducing costs, reducing the time volunteers must take from their normal lives, and making resources more available for other missions if needed.

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  • Active and Passive Radar Detection and Equipment

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