メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((141.911006491688 43.5012546812747, 141.910102611027 43.5014016831396, 141.909806763256 43.5005376158434, 141.910110211003 43.5004475522128, 141.910722436513 43.5003361489277, 141.911006491688 43.5012546812747)) ^^http://www.opengis.net/ont/geosparql#wktLiteral