Eight male unacclimatized subjects were selected for the present investigation. The subjects were all in excellent health and ranged in age between 25 and 35 years. Subjects performed one-dimensional horizontal compensatory tracking, the Critical Instability Tracking Task (CITT), in each of eight environmental conditions for an hour. Two levels of ambient temperature were used: 22°C (72°F) and 35°C (95°F). Two levels of relative humidity were used: 45% RH and 80% RH. The resulting Wet-bulb Globe Temperatures were 18°C (64°F) WBGT, 21°C (70°F) WBGT, 29°C (85°F) WBGT, and 34°C (93°F) WBGT. Two levels of tracking difficulty were used: easy ()λlow = 1.0 and λhigh = 2.0) and moderate (λlow = 1.0 and λhigh = 5.0). Prior research has demonstrated that both ambient temperature and tracking difficulty affected significantly tracking performance (root-mean-square error) and perceived workload (SWAT rating). However, in this study, humidity did not affect either measure significantly. This might be attributable to the upper bound of humidity (80% RH) used in this research. Therefore, research needs to be done above 80% RH to examine the effects of humidity in further detail. Results also indicated that the Subjective Workload Assessment Technique (SWAT) can be used as a good indicator of the actual changes in mental workload on tracking in heat. Finally, results showed that tracking performance decrement occurred at a lower temperature (29°C (85°F) WBGT) than did the perception of significant mental workload on tracking (which occurred at 34°C (93°F) W8GT). / Master of Science
| Identifer | oai:union.ndltd.org:VTETD/oai:vtechworks.lib.vt.edu:10919/41033 |
| Date | 13 February 2009 |
| Creators | Kim, Seong-Han |
| Contributors | Industrial and Systems Engineering, Price, Dennis L., Snyder, Harry L., Casali, John G. |
| Publisher | Virginia Tech |
| Source Sets | Virginia Tech Theses and Dissertation |
| Language | English |
| Detected Language | English |
| Type | Thesis, Text |
| Format | x, 99 leaves, BTD, application/pdf, application/pdf |
| Rights | In Copyright, http://rightsstatements.org/vocab/InC/1.0/ |
| Relation | OCLC# 24485918, LD5655.V855_1991.K57.pdf |
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