failed state

IRI: https://spec.industrialontologies.org/ontology/construct/FailedState

Defined In: https://spec.industrialontologies.org/ontology/maintenance/Maintenance/

SubClass Of: maintenance state

Class Hierarchy

owl:Thingbfo:entitybfo:occurrentbfo:processmaterial statemaintenance statefailed state

Definition

state of an item being unable to perform a required function due to a failure event

Semi-Formal Definition:

“failed state’: every instance of ‘failed state’ is defined as exactly an instance of ‘maintenance state’ o1 that ‘has participant at all times’ some ‘maintainable material item’ i and that is ‘initiated by’ some ‘failure event’ and is ‘preceded by’ some (‘degraded state’ or ‘operating state’) o2 that ‘has participant at all times’ i and there is no (‘degraded state’ or ‘operating state’ ) o3 such that o3 ‘has participant at all times’ i and o2 ‘precedes’ o3 and o3 ‘precedes’ o1”

Examples

  • is broken in two, is burst, is failing to turn on

Formal Axioms

First-Order Logic Definition

FailedState(o1) ↔ MaintenanceState(o1) ∧ ∃i(MaintainableMaterialItem(i) ∧ hasParticipantAtAllTimes(o1, i) ∧ ∃e(FailureEvent(e) ∧ initiates(e, o1)) ∧ ∃o2((DegradedState(o2) ∨ OperatingState(o2) ∧ hasParticipantAtAllTimes(o2,i)) ∧ precedes(o2, o1)) ∧ ¬∃o3((DegradedState(o3) ∨ OperatingState(o3)) ∧ hasParticipantAtAllTimes(o3,i) ∧ precedes(o2, o3) ∧ precedes(o3, o1)))

Description Logic