The performance of a decision making unit (DMU) can be evaluated in either across-sectional or a time-series manner, and data envelopment analysis (DEA) is a useful method for both types of evaluation. The Malmquist productivity index (MPI) evaluates the change in efficiency of a DMU between two time periods. It is defined as the product of the Catch-up and Frontier-shift terms. In this pape...

A literature review of 105 studies on the effects of extended daily working hours was conducted. Potential negative effects of extended working hours are discussed: More accidents on the job; more accidents off the job; reduced duration and quality of sleep due to moonlighting; sleepiness; reduced alertness; fatigue; adverse effects on performance; prolonged toxic exposure; adverse effects on h...

In scheduling literature, the notion of machine non-availability periods is well known, for instance for maintenance. In our case of planning chemical experiments, we have special periods (the week-ends, holidays, vacations) where the chemists are not available. However, human intervention by the chemists is required to handle the starting and termination of the experiments. This gives rise to ...

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