Relation SUBCOMPONENT-OF

• Defined in theory: Component-assemblies
• Source code: component-assemblies.lisp

Slots on this relation:

Documentation:

(subcomponent-of ?sub ?super) means that the component ?sub
is structurally a part of component ?super. A component cannot be a subcomponent of itself (irrreflexivity) and two components cannot be subcomponents of each other (antisymmetrity).

This is a primitive relation. Formally, any irreflexive and antisymmetric relation defined only on components will satisfy this definition.

Note that the subcomponent-of relation does not name the parts of a component. That is, the subcomponent links are unlabeled arcs. For named subcomponent relations, see has-subpart-slot.

Instance-Of: Antisymmetric-relation, Irreflexive-relation, Relation

Arity: 2

Domain: Component

Range: Component

Other Related Axioms:

(=> (Subcomponent-Of $X $Y) (Component $Y))

(=> (Subcomponent-Of $X $Y) (Component $X))

(<=> (Has-Subcomponent $Arg1 $Arg2) (Subcomponent-Of $Arg2 $Arg1))

(Inverse Has-Subcomponent Subcomponent-Of)

(=> (Connected-Components ?A ?B)
    (And (Not (Subcomponent-Of ?A ?B)) (Not (Subcomponent-Of ?B ?A))))

(=> (Has-Subpart-Slot ?Component ?Subpart-Slot)
    (And (Value-Cardinality ?Component ?Subpart-Slot 1)
         (Forall (?X)
                 (=> (Instance-Of ?X ?Component)
                     (Subcomponent-Of (Value ?Subpart-Slot ?X)
                                      ?Component)))))

Notes:

• What about transitivity?

  A main difference betweeen components and arbitrary globs of matter is that components are object-like in a modeling sense; thus, a subcomponent is not an arbtrary subregion, but a part of a system with a stable identity as its part. If subcomponent-of were transitive, then there would be no level boundaries between a component and its subcomponents and their subcomponents; for modularity reasons, the system modeler describes the subcomponents of a component as black boxes, rather than as arbitrary regions.

• What about mereology?

  Mereological theories are concerned with the validity of axiomatic assumptions about part/whole relationships as applied to the physical world. That is why they often insist that the part relation is transitive. This ontology provides abstractions for engineering modeling; it is the modeler's obligation to apply them meaningfully to physical domains.

  (see-also has-subcomponent subpart-slot-of)