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Now we introduce two armatures with the properties from the descriptive model above. Assume that, due to the piping, pumps #1 and #2 are controlled by both armatures, whereas A200 regulates pump #3 only. This situation is depicted below already indicating, that the implementation of the relation requires a more complex structure. We find three pumps on the left side and two armatures on the right side of the relation, respectively. Managing this control relation in the metamodel requires to introduce a relation block „CONTROL“ with two metaproperties „Armature#“ and „Pump#“
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Lets have a closer look at the characteristics of the two methods relating objects:
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