UNL Knowledge Base

The UNL Knowledge Base, or simply UNL^KB, constitutes a network structure where UWs are interconnected through Universal Relations of UNL. Differently from the UNL Ontology, which deals only with hierarchical relations ("icl" and "iof"), the UNL^KB comprises any relation necessary to define a given UW. In that sense, the UNL^KB contains and extends the UNL Ontology, and it is expected to include all the information normally available in ordinary dictionaries and thesauri. The UNL^KB is also a part of the UNL Memory, a network structure that includes not only the essential (necessary) information about a concept but also the accidental information extracted from corpora.

The UNL^KB may be provided in two different formats:

• Extended, in XML; or
• Simplified, as a set of network disambiguation rules

Extended format

UNL^KB entries in extended format must have the following structure:

<relation name="RNAME" type="RTYPE" frequency="RFREQ">
  <source id="SID" attribute="ATT" lang="UNL" frequency="SFREQ" class="SCLASS">SOURCE</source>
  <target id="TID" attribute="ATT" lang="UNL" frequency="TFREQ" class="TCLASS">TARGET</target>
</relation>

Where:
RNAME is the name of one existing UNL relation ("agt", "aoj", "obj", etc);
RTYPE is the type of the existing relation
RFREQ is the frequency of the relation TYPE between the SOURCE and the TARGET in the corpus;
SFREQ is the frequency of the SOURCE in the corpus;
TFREQ is the frequency of the TARGET in the corpus;
SID is a number used to identify the SOURCE;
TID is a number used to identify the TARGET;
ATT is one of the existing UNL attributes ("entry", "past", etc);
SCLASS is the general class of the SOURCE;
TCLASS is the general class of the TARGET;
SOURCE is the source node of the UNL relation;
TARGET is the target node of the UNL relation;

XML Schema

<?xml version="1.0" encoding="utf-16"?>
<xsd:schema attributeFormDefault="unqualified" elementFormDefault="qualified" version="1.0" xmlns:xsd="http://www.w3.org/2001/XMLSchema">
 <xsd:element name="kb">
   <xsd:complexType>
     <xsd:sequence>
       <xsd:element maxOccurs="unbounded" name="relation">
         <xsd:complexType>
           <xsd:sequence>
             <xsd:element name="source">
               <xsd:complexType>
                 <xsd:attribute name="id" type="xsd:unsignedLong" use="required" />
                 <xsd:attribute name="attribute" type="xsd:string" use="optional" />
                 <xsd:attribute name="lang" type="xsd:string" use="optional" />
                 <xsd:attribute name="frequency" type="xsd:int" use="optional"/>
                 <xsd:attribute name="class" type="xsd:string" use="optional"/>
               </xsd:complexType>
             </xsd:element>
             <xsd:element name="target">
               <xsd:complexType>
                 <xsd:attribute name="id" type="xsd:unsignedLong" use="required"/>
                 <xsd:attribute name="attribute" type="xsd:string" use="optional" />
                 <xsd:attribute name="lang" type="xsd:string" use="optional"/>
                 <xsd:attribute name="frequency" type="xsd:int" use="optional"/>
                 <xsd:attribute name="class" type="xsd:string" use="optional"/>
               </xsd:complexType>
             </xsd:element>
           </xsd:sequence>
           <xsd:attribute name="name" type="xsd:string" use="required"/>
           <xsd:attribute name="type" type="xsd:string" use="optional"/>
           <xsd:attribute name="frequency" type="xsd:int" use="optional"/>
         </xsd:complexType>
       </xsd:element>
     </xsd:sequence>
   </xsd:complexType>
 </xsd:element>
</xsd:schema>

Example

<?xml version="1.0" encoding="utf-16"?>
<kb>
 <relation name="mod" frequency="2">
  <source id="410" attribute="entry" lang="UNL" frequency="20" class="nou">book(icl>document)</source>
  <target id="2243" lang="UNL" frequency="2" class="nou">republic(icl>form of government)</target>
 </relation>
 <relation name="mod" frequency="1">
  <source id="410" attribute="entry" lang="UNL" frequency="20" class="nou">book(icl>document)</source>
  <target id="466" lang="UNL" frequency="1" class="nou">certainty(icl>attribute)</target>
 </relation>
 <relation name="mod" frequency="1">
  <source id="410" attribute="entry" lang="UNL" frequency="20" class="nou">book(icl>document)</source>
  <target id="583" lang="UNL" frequency="2" class="nou">creation(icl>action)</target>
 </relation>
 <relation name="mod" frequency="1">
  <source id="410" attribute="entry" lang="UNL" frequency="20" class="nou">book(icl>document)</source>
  <target id="1539" lang="UNL" frequency="3" class="nou">lineage(icl>descendant)</target>
 </relation>
 <relation name="mod" frequency="1">
  <source id="410" attribute="entry" lang="UNL" frequency="20" class="nou">book(icl>document)</source>
  <target id="1566" lang="UNL" frequency="11" class="nou">love(icl>emotion)</target>
 </relation>
</kb>

Simplified format

UNL^KB entries in simplified format must have the structure of network disambiguation rules, as follows:

RELATION(SOURCE;TARGET)=DC;

Where:
RELATION is the name of one existing UNL relation ("agt", "aoj", "obj", etc);
SOURCE is the source node of the UNL relation;
TARGET is the target node of the UNL relation;
DC is the degree of certainty (i.e., the likelihood of the relation between the SOURCE and the TARGET), ranging from 0 (impossible) to 255 (necessary)
The SOURCE and the TARGET nodes may be referred as:

• constants (i.e., specific UWs), to be represented between double square brackets: [[103485997]]
• a feature (attribute, value, or attribute-value pair) or set of features of a group of UWs: N, LEX=N, N&ABT
• a relation or a set of relations: agt(N,V)

Examples

icl(<[[100001930]];[[100001740]])=1; (= a physical entity is a kind of entity)
pof(N;V)=0; (= a nominal concept cannot be a part of a verbal concept)
pof(LEX=N;LEX=V)=0; (= a nominal concept cannot be a part of a verbal concept)
icl(ABT;^ABT)=0; (= an abstract concept cannot be a kind of non-abstract concept)
and(agt(;);^agt(;))=0; (= an agent relation may not be coordinated with a non-agent relation)