| 要約: | An effort has been made in this thesis to estimate the time for fatigue of a human
operator based on the workload. Workload in turn depends on the condition of the
operator and environmental conditions, which is reflected in the muscle temperature.
Simple yet comprehensive mathematical models for heat transfer in human body were
developed for both steady as well as transient states. Conduction, convection,
radiation, and evaporation modes of heat transfer were considered in the models. The
models were also validated against the results available in the literature. Parametric
studies involving the condition of the operator and the environment were also carried
out. From the mathematical model muscle temperature required for the estimation of
the time for fatigue of the operator was determined.
Three case studies from a multinational company were considered which involve
different types of task. The time for fatigue has been estimated for the three cases by
mathematical calculation and compared with the actual time for fatigue of the operator,
which is obtained from by interviewing the operators. It is observed that for these case
studies the estimated value and also the actual value are in close agreement, e.g. case
study 1 estimated value of time to fatigue is 0.56 minute and actual time to fatigue is
0.6 minute which shows that the calculated value is in close agreement with the actual
value. Similarly for case study 2 the calculated value is 0.15 minute in compared to the
actual value of 0.18 minute. The same result was also obtained for case study 3
whereby the actual result is 0.22 minute versus the predicted value of 0.26 minute.
As the predicted value and the actual time are in close agreement it has been
proposed that the same type of analysis can be expanded to other fatiguing tasks
across the industry.
|
|---|
