Physical modeling enables you to produce models that can be easily
reused and shared with other engineers. Importing data and models from
other environments helps ensure the accuracy of your models. By
integrating those models with control and signal processing algorithms,
you can test for integration errors early in the design process. The logical model defines the business entities that will be
rendered by the application and what policies and rules will be used to
operate on those entities. The questions this model answers are very
specific to the business for which you are writing your application.