メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((141.710784965363 44.3718373171734, 141.710266406509 44.3721879761326, 141.709714114947 44.3725338657744, 141.708589897068 44.3716623462165, 141.709681887619 44.3709692827667, 141.710784965363 44.3718373171734)) ^^http://www.opengis.net/ont/geosparql#wktLiteral