Sorry! No search in Internet Explorer.
The URL (web address) shown by your browser starts with https because you visit this site using a secured connection. Note that the URI reference (identifier) of PROCESS PLANT IDENTIFICATION CODE ASSIGNMENT CLASS (dexpi) to be used in DEXPI-compliant Proteus files starts with http - as shown below:

http://sandbox.dexpi.org/rdl/ProcessPlantIdentificationCodeAssignmentClass

PROCESS PLANT IDENTIFICATION CODE ASSIGNMENT CLASS (dexpi)

RDF Properties

"PROCESS PLANT IDENTIFICATION CODE ASSIGNMENT CLASS"
"PROCESS PLANT IDENTIFICATION CODE ASSIGNMENT CLASS"

Namespaces

rdfs
http://www.w3.org/2000/01/rdf-schema#
pca
http://data.posccaesar.org/rdl/
dexpi
http://sandbox.dexpi.org/rdl/