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The UML class name is used for the element names in the XML Schema.

 Mapping Data Types

<<codelist>>

Codelists are given by the stereotype <<codelist>>. As it can be seen from the diagram elow, for each <<codelist>> type, there also is a <<datatype>> class, which defines the nilReason attribute.
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First, the <<codelist>> class is converted into a simpleType in the XSD: 
<simpleType name="CodeAircraftEngineBaseType">
<annotation>
<appinfo><gml:description>A code indicating the type of aircraft engine (for example, jet, piston, turbo).</gml:description></appinfo>
</annotation>
<union>
<simpleType>
<restriction base="xsd:string">
<enumeration value="JET">
<annotation>
<appinfo><gml:description>Jet Engine</gml:description></appinfo>
</annotation>
</enumeration>
<enumeration value="PISTON">
<annotation>
<appinfo><gml:description>Piston Engine</gml:description></appinfo>
</annotation>
</enumeration>
<enumeration value="TURBOPROP">
<annotation>
<appinfo><gml:description>Turbo Propeller Engine</gml:description></appinfo>
</annotation>
</enumeration>
<enumeration value="ALL">
<annotation>
<appinfo><gml:description>All aircraft engine types.</gml:description></appinfo>
</annotation>
</enumeration>
</restriction>
</simpleType>
<simpleType>
<restriction base="string">
<pattern value="OTHER(\w|_){1,58})?"/>
</restriction>
</simpleType>
</union>
</simpleType> 
Note that the simple data types is declared as a union between the enumerated values declared in the UML model (with the exception of the value "OTHER") and a string with the pattern "OTHER(\w|_){1,58})?". This enables <<codelist>> data types to include values that are not supported by the enumeration list. For example, an electric engine type could be encoded as "OTHER:ELECTRIC". 
In addition, a complex type is defined, including the declaration of the nilReason attribute: 
<complexType name="CodeAircraftEngineType">
<simpleContent>
<extension base="aixm:CodeAircraftEngineBaseType">
<attribute name="nilReason" type="gml:NilReasonEnumeration"/>
</extension>
</simpleContent>
</complexType> 

<<datatype>> - default case

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<<datatype>> with Unit of Measurement

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Particular cases

<<datatype>> with no BaseType

The 5 data types listed in ‎2.7.1.1 map directly to the built-in datatypes defined by the XML schema specification. The default datatypes are string, float, double, etc, which are considered simpleTypes.
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The AlphaType acts as a convenient example.
!worddav1107a322f49687c3c72f01441b7793fd.png|height=210,width=281!
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<<span style="color: #000080"><strong>simpleType</strong></span> name="<span style="color: #000080"><strong>AlphaType</strong></span>">
 <restriction base="xsd:<span style="color: #000080"><strong>string</strong></span>">
  <pattern value="\[A-Z\]*"/>
 </restriction>
</simpleType>
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<<datatype>> XHTMLBaseType

<<datatype>> XHTMLBaseType represents a structured XHTML document compliant with http://www.w3.org/1999/xhtml. It should be mapped as follows in XML: 
<complexType name="XHTMLBaseType">
<sequence>
<any namespace="http://www.w3.org/1999/xhtml" minOccurs="1" maxOccurs="unbounded" processContents="skip"/>
</sequence>
</complexType>

(draft text for AIXM 5.2) Deprecation of an element inside the AIXM XSD Schema

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