We use a graphical norm to unify the way we communicate both internally and with customers about their problem. This norm can be seen as an extension to the plate notation. It is used to draft models of the optimization problem we are tackling.
This tool allows us to quickly identify the main components of a problem and devise the first "rough" models.
The figure below describes this norm and gives a simple example. Same picture is available in a SVG format: legend_eng.svg
The main concepts that are represented in this figure are explained in Main Concepts for Optimization Problems.