Analysis and Scheduling for Flexible Job Shop Problem based on Unreliable Degraded Machine Model and Finite Buffers

In recent decades, the Flexible Job Shop Scheduling Problem (FJSP) has been widely studied. From a theoretical perspective, the FJSP with a fixed number of jobs has attracted significant attention. In actual production environments, machine performance can fluctuate due to factors such as workload and maintenance status, and machine performance does not remain constant but changes with the processing of workpieces. Therefore, it is necessary to study a FJSP model based on unreliable degraded machines and finite buffers. In this paper, a model of unreliable degraded machine is established, and the processing time of workpieces on degraded machines is calculated based on this model. Using the accurate processing times, an improved genetic algorithm is employed to solve the scheduling problem in flexible job shop production. The effectiveness of the algorithm is verified through numerical experiments.