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Framework for Knowledge Representation and Reasoning for Self-Adaptive Systems


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Description

A GOAL in KnowLang is a desirable transition to a state or a transition from a specific state to another state (see the examples below). A system running the KnowLang Reasoner may transit to a state when the properties of concept are updated or some errors or events have occurred, or actions have been realized in the system itself, or in the operational environment. Goals are used to specify policies.

Note that the KnowLang Reasoner relies on TELL and GET operators to change the defined states. Recall that in KnowLang, a state is a Boolean expression over ontology.

Example
//Goals
CONCEPT_GOAL TakeJourney {
  CHILDREN {eMobility.eCars.CONCEPT_TREES.Goal}
  PARENTS {}
  SPEC {
    DEPART { eMobility.eCars.CONCEPT_TREES.Journey.PROPS.journeyRoute.STATES.AtBeginning }
    ARRIVE { eMobility.eCars.CONCEPT_TREES.Journey.PROPS.journeyRoute.STATES.AtEnd }
  }
}
CONCEPT_GOAL ArriveOnTime {
  CHILDREN {eMobility.eCars.CONCEPT_TREES.Goal}
  PARENTS {}
  SPEC {
    DEPART { eMobility.eCars.CONCEPT_TREES.Journey.PROPS.journeyRoute.STATES.AtEnd }
    ARRIVE { eMobility.eCars.CONCEPT_TREES.Journey.STATES.ArrivedOnTime }
  }
}
CONCEPT_GOAL LowRouteTraffic {
  CHILDREN {eMobility.eCars.CONCEPT_TREES.Goal}
  PARENTS {}
  SPEC {
    DEPART { eMobility.eCars.CONCEPT_TREES.Route.STATES.InHighTraffic }
    ARRIVE { eMobility.eCars.CONCEPT_TREES.Route.STATES.InLowTraffic }
  }
}
CONCEPT_GOAL SufficientBattery {
  CHILDREN {eMobility.eCars.CONCEPT_TREES.Goal}
  PARENTS {}
  SPEC {
    DEPART { eMobility.eCars.CONCEPT_TREES.Journey.STATES.InSufficientBattery }
    ARRIVE { eMobility.eCars.CONCEPT_TREES.Journey.STATES.InSufficientBattery }
  }
}

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User Guide Curator - Emil Vassev
Last modified on January 28, 2014