tml:positionRelation 

For describing positional relations of subjects external to a system.  An empty posRelation tag in a data indicates that this uidRef relation is no longer exist

Element Information

Model

tml:spaceCoordSystem{0,1} , tml:spaceRefSystem{0,1} , tml:refObjUidRef{0,1} , tml:spaceCoords* , tml:objUidRef*
Children: tml:objUidRef, tml:refObjUidRef, tml:spaceCoordSystem, tml:spaceCoords, tml:spaceRefSystem

Attributes

QName Type Fixed Default Use Inheritable Annotation
name xs:string optional 
short descriptive name of element
uid xs:anyURI optional 
unique ID for this element
uidRef xs:anyURI optional 
the contents of this element are exactly the same as the contents of the uidRef element. no need repeating it. (similar to xlink)

Source 

<xs:element name="positionRelation" minOccurs="0" maxOccurs="unbounded">
  <xs:annotation>
    <xs:documentation>For describing positional relations of subjects external to a system. An empty posRelation tag in a data indicates that this uidRef relation is no longer exist</xs:documentation>
  </xs:annotation>
  <xs:complexType>
    <xs:complexContent>
      <xs:extension base="tml:SpatialCoordType">
        <xs:sequence>
          <xs:element name="objUidRef" type="tml:BindType" minOccurs="0" maxOccurs="unbounded">
            <xs:annotation>
              <xs:documentation>uid of the obj being positioned. multiples allowed if in same position and orientation</xs:documentation>
            </xs:annotation>
          </xs:element>
        </xs:sequence>
      </xs:extension>
    </xs:complexContent>
  </xs:complexType>
</xs:element>

Sample