清楚的本体关系定义

http://www.w3.org/TR/owl-ref/

3.1.2.1 Value constraints
3.1.2.1.1 owl:allValuesFrom 所有属性的取值都是来自
The value constraint owl:allValuesFrom is a built-in OWL property that links a restriction class to either a class description or a data range. A restriction containing an owl:allValuesFrom constraint is used to describe a class of all individuals for which all values of the property under consideration are either members of the class extension of the class description or are data values within the specified data range. In other words, it defines a class of individuals x for which holds that if the pair (x,y) is an instance of P (the property concerned), then y should be an instance of the class description or a value in the data range, respectively.

A simple example:





This example describes an anonymous OWL class of all individuals for which the hasParent property only has values of class Human. Note that this class description does not state that the property always has values of this class; just that this is true for individuals that belong to the class extension of the anonymous restriction class.

NOTE: In OWL Lite the only type of class description allowed as object of owl:allValuesFrom is a class name.

An owl:allValuesFrom constraint is analogous to the universal (for-all) quantifier of Predicate logic - for each instance of the class that is being described, every value for P must fulfill the constraint. Also notice that the correspondence of owl:allValuesFrom with the universal quantifier means that an owl:allValuesFrom constraint for a property P is trivially satisfied for an individual that has no value for property P at all. To see why this is so, observe that the owl:allValuesFrom constraint demands that all values of P should be of type T, and if no such values exist, the constraint is trivially true.

3.1.2.1.2 owl:someValuesFrom 至少有些个体的值来自class desc or data value in range
The value constraint owl:someValuesFrom is a built-in OWL property that links a restriction class to a class description or a data range. A restriction containing an owl:someValuesFrom constraint describes a class of all individuals for which at least one value of the property concerned is an instance of the class description or a data value in the data range. In other words, it defines a class of individuals x for which there is at least one y (either an instance of the class description or value of the data range) such that the pair (x,y) is an instance of P. This does not exclude that there are other instances (x,y') of P for which y' does not belong to the class description or data range.

The following example defines a class of individuals which have at least one parent who is a physician:





The owl:someValuesFrom constraint is analogous to the existential quantifier of Predicate logic - for each instance of the class that is being defined, there exists at least one value for P that fulfills the constraint.

NOTE: In OWL Lite the only type of class description allowed as object of owl:someValuesFrom is a class name.

3.1.2.1.3 owl:hasValue
The value constraint owl:hasValue is a built-in OWL property that links a restriction class to a value V, which can be either an individual or a data value. A restriction containing a owl:hasValue constraint describes a class of all individuals for which the property concerned has at least one value semantically equal to V (it may have other values as well).

NOTE: for datatypes "semantically equal" means that the lexical representation of the literals maps to the same value. For individuals it means that they either have the same URI reference or are defined as being the same individual (see owl:sameAs).

NOTE: the value constraint owl:hasValue is not included in OWL Lite.

The following example describes the class of individuals who have the individual referred to as Clinton as their parent:





3.1.2.2 Cardinality constraints