Relation dl#part (entity,entity)  the subpart may or may not be different from the whole
  supertype:  part_in_Dolce_Lite (pm)  immediate_relation  transitive_relation (pm)
  instance of:  transitive_relation_type (pm)
  inverse:  part_of
  subtype:  component (entity,entity)
  subtype:  atomic_part (entity,atom)  an undivisible part
     subtype:  temporary_atomic_part__AtP (entity,atom)