<http://schema.org/keywords>
"\u30CB\u30B3\u30E9\u30A4\u30FB\u30E9\u30E0 \u60F3\u50CF\u753B Wi-Fi"^^<http://www.w3.org/2001/XMLSchema#string>
<http://www.huffingtonpost.jp/2013/07/24/nickolay_lamm_wifi_n_3642769.html>