Constructing Hierarchical Modular Models in Alternative and Interchangeable Representations

Modelers should be empowered to develop component-based models incrementally and iteratively using different modalities. They should not be required to work with an entire model hierarchy or be constrained to pre-defined sub-hierarchy levels that can impose limitations on the visual development of models. This paper introduces a novel visual modeling capability where modelers can work with any sub-hierarchy with any finite number of arbitrary levels and branches. The structural representation of the components with their input/output relationships conforms to the system-theoretic DEVS models and broadly Reactive Modules. Additionally, it is advantageous for the visual and logical aspects of models to be stored and retrieved in databases. Visual models can be generated from their logical counterparts stored in the NoSQL database. A framework supporting a unified logical, visual, and persistent modeling is developed. The framework aids modelers in constructing structural models at scale for simulation and Digital Twins.