Methods, mediums and systems are provided to enable a user to build and edit a UML model for a system containing one or more physical component, which includes the across variable and/or the through variable of the components. A UML model may include classifiers, such as classes, interfaces, datatypes, signals, components, nodes, use cases and subsystems, that describes the structural and behavioral features of the system. A UML model may include at least one of the classifiers that is described using the across variables and/or the through variables of the system. For example, the interface of a component in a UML model may be described using the across variables and/or the through variables of the component.