Direct database-simulation using PROGRESS

The paper introduces a new concept called `direct database-simulation´ which uses relational database data as the simulation model for simulation-based scheduling in a job-shop environment. The application is in a large machine shop of 200 machining centres producing precision machine tools. The direct database-simulation scheduler was developed on PROGRESS (an application development environment centred on a relational database management system) to address the problem of finite capacity scheduling of the machine shop. It is shown that the concept is feasible and performance measures such as tardiness and machine utilisation are improved by an order of 20%