Equipment Managers (EMs) play a major role in a Manufacturing Execution System (MES). They serve as the communication bridge between the components of an MES and the equipment. The purpose of this paper is to propose a novel methodology for developing analytical and simulation models for the EM such that the validity and performance of the EM can be evaluated. Domain knowledge and requirements are collected from a real semiconductor packaging factory. By using IDEFO and state diagrams, a static functional model and a dynamic state model of the EM are built. Next, these two models are translated into a Petri net model. This allows qualitative and quantitative analyses of the system. The EM net model is then expanded into the MES net model. Therefore, the performance of an EM in the MES environment can be evaluated. These evaluation results are good references for design and decision making.

The equipment manager plays one of the major roles in a manufacturing execution system (MES). It is the communication bridge between the components of MES and the equipment. The soul of an equipment manager is its control algorithm. The purpose of this paper is to develop such a control algorithm. The domain knowledge and requirements are collected from a real semiconductor packaging factory. By using the IDEF0 methodology and the system state diagrams, the functional model and the dynamic model of the control algorithm are built. Then, the control algorithm is translated into the Petri-net model. This allows the qualitative and quantitative analysis of the system. The Petri-net model of the equipment manager is included into the MES Petri-net model. As such, the performance of an equipment manager in the MES environment can be evaluated. These evaluation results are good references for design and decision-making. Finally, the proper control algorithm is converted into the application program of the equipment manager.

In this paper, a Petri net-based perturbation analysis method with respect to structural changes is presented. The structural change of a generalized stochastic Petri net will modify its underlying reachability graph and its invariants, and so one approach is to reevaluate the entire model. However, if one uses the Petri net's structural properties, one can find the perturbed reachability graph without another analysis. Also, one can find the relationship between the original and new transition rate matrices. The net result is that less memory space is needed and less computational time is needed to get the state probability sensitivities and the performance sensitivities.>