user defined datatype in owl

Hi,

Is it possible in owl to:

  *   define user defined datatypes? for example, a complex number datatype, which is not a built-in datatype and could be defined as the couple [real part, imaginary part]. Another example is to define a numerical-value datatype as the union of xsd:float, xsd:int, xsd:short, xsd:long,...
  *   use these datatypes as the range of DataProperties?

In case this is possible, which owl construct should I use to define them?

Thank you in advance for your help,

Fano

Orange Restricted

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