Event-modeled Risk Assessment Using Linked Diagrams
In order to develop a dynamic probabilistic risk assessment capability, a prototype discrete event simulator was created as part of an LDRD that can model dynamic systems and generate probabilistic risk/reliability results. The development consisted of three major parts: 1. Development of a discrete event modeling software library 2. Design of a simulation object model for dynamic modeling 3. Construction of the graphical user interface (GUI) that will allow risk assessment analysts to more easily develop these models We called this new tool EMRALD. A key part of the EMRALD tool has been to develop an object-oriented software model that is flexible enough to support the varied dynamic simulation models (e.g., fails to operate, fails on demand). An object-oriented approach better matches the simulation model to real world objects and makes it more intuitive for the modeler. The interface represents actual physical components, specifically tracking how they interact. EMRALD is a discrete-event simulation tool that is coupled with a state-based diagramming graphical user interface. A key part of the EMRALD tool has been to develop an object-oriented software model that is flexible enough to support the varied dynamic simulation models (e.g., fails to operate, fails on demand). By having a state-based approach, we can integrate different hazards into a single comprehensive model. For example, a single model can include fire, flooding, transient, and seismic initiating events -- each of these events becomes a trigger into the state-based approach that tell the model to make a transition based upon the specific initiator. An object-oriented approach better matches the simulation model to real world objects and makes it more intuitive for the modeler. The interface represents actual physical components, specifically tracking how they interact.