Notice of RetractionAn EMQ model with maintenance time in a production system

Notice of Retraction

After careful and considered review of the content of this paper by a duly constituted expert committee, this paper has been found to be in violation of IEEE´s Publication Principles.

We hereby retract the content of this paper. Reasonable effort should be made to remove all past references to this paper.

The presenting author of this paper has the option to appeal this decision by contacting TPII@ieee.org.

Economic Manufacturing Quantity (EMQ) models assume that maintenance time consumed by inspection and restoration in the production cycle is negligible. This paper addresses the joint problem of production planning and inspection schedules with considering maintenance time under the realistic assumptions that the elapsed time until the production process shift is exponentially distributed and the optimal production run and maintenance schedule are equal-interval. A simple model has been developed for the simultaneous determination of the length of the production run and the number of inspections for a deteriorating production system with considering maintenance time. Then the problem is solved by using an approximation to the cost function. The resulting EMQ model is found to be an adjustment to that ignoring maintenance time. Finally, the relationships of optimal production run time or the optimal number of inspections and cost penalty by using the two models are examined.