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The Effects of Work/Rest, Target Activity, Background Noise, and String Size on Operator Interpretation of Unattended Ground Sensor Records

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Technical paper

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It was required to investigate the relationships between unattended ground sensor UGS operator performance and workrest cycles, sensor string size, target activity levels, and noisyquiet environments and to identify sources of operator error that can be eliminated through the use of new interpretation techniques, procedures, and training. The procedure was Operators monitored UGS records for 8 hours of worktime under four different workrest conditions 2 hours works, 1 hour rest 2 hours work, 15 minutes rest 4 hours work, 1 hour rest and 4 hours work, 15 minutes rest. The UGS records included counterbalanced variations of three string sizes 2, 3, and 4 sensors, 12 targets per hour or 6 targets per hour, and high and low battle noise. The results were For a contemplated 8 hours of monitoring, 2-hour work shifts interspersed with 1-hour or 15-minute rest periods are to be preferred over 4-hour work shifts interspersed with 1-hour or 15-minute rest periods. For heavy short-term monitoring requirements, for example, enemy attack requiring periods of concentrated monitoring, an operator can perform satisfactorily for one 4-hour shift but performance will deteriorate during a second 4-hour shift. Performance was equal using 2, 3, or 4 sensor strings in the low-target-activity condition. However, during the high-target-activity condition, use of 3 or 4 sensor strings resulted in more target detections as compared to use of 2 sensor strings. Operator performance during the high battlefield noise was equal to that during low noise. During the high-target-activity conditions the operators detected more targets than during the low-target-activity condition.

Subject Categories:

  • Acoustic Detection and Detectors
  • Magnetic and Electric Field Detection and Detectors
  • Human Factors Engineering and Man Machine Systems

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