Multi-objective performance analysis of one-machine manufacturing systems

Achieving of the desired performance for manufacturing systems is one very important goal when solving of planning and scheduling tasks. Corresponding management of orders and invested assets demands for multi-level and multi-objective optimization. Software systems of Enterprise Resource Planning (ERP) and Manufacturing Execution System (MES) applications used presently in practice are based on different modeling approaches. However, most of involved mathematical models use a set of complicated production equations. In these equations, released jobs and operation rates (as input) can be considered as the most important parameters that may play the controlling role of the production. The considered mathematical models usually evaluate three key performance indices (KPIs) of great importance. These indices are as follows: 1. Readiness for delivery, 2. Stock or WIP (work-in-progress) level, 3.Utilization rate of resources. These indices can be considered as objective functions not only for manufacturing systems, but for the entire enterprise, too. Unfortunately these indices depend on each other and influence each other in an opposite way. A basic requirement of control policy is production stability. In the case of stable production, there is a general correspondence among the average performance indices together with the average released job set or production-rate parameters. These are analyzed for one-machine manufacturing systems.