Erect means build or upright. If you erect a house, you build it. If you stand erect, you hold your body as tall as possible.
A mathematical model is a description of a system using mathematical concepts and language.The process of building a mathematical model is termed mathematical modeling.Mathematical models are used in the natural sciences (such as physics, biology, earth science, meteorology) and engineering disciplines (e.g. computer science, artificial intelligence). mathematical model is a description of a system using mathematical concepts and language.
The analysis model is the primary artifact of the workflow detail called Analyze Behavior (see Figure 6). It is a platform independent model (PIM), which means that it does not contain technology-based decisions. For example, it would be an error to place a JDBC class in this model.