public function setCachedString($_string, $_key, $_ttl = 7200)
 {
     $_obj = new Memcache();
     $_cacheConnected = $_obj->get('memcacheconnected');
     if ($_cacheConnected) {
         if (is_array($_string)) {
             $_obj->cacheSet($_key, serialize($_string), $_ttl);
         } else {
             $_obj->cacheSet($_key, $_string, $_ttl);
         }
     }
     unset($_obj);
     return $_string;
 }