<http://schema.org/keywords>
"\u4E16\u754C\u4E00\u9AD8\u3044\u30D3\u30EB"^^<http://www.w3.org/2001/XMLSchema#string>
<http://www.huffingtonpost.jp/2013/06/27/burj_khalifa_google_street_view_n_3508813.html>