var http_request=null
function createXmlHttpRequest(){
   if (window.XMLHttpRequest) {
      http_request = new XMLHttpRequest();
    } else if (window.ActiveXObject) { 
      try {
        http_request = new ActiveXObject("Msxml2.XMLHTTP");
      } catch (e) {
        try {
          http_request = new ActiveXObject("Microsoft.XMLHTTP");
        } catch (e) {}
      }
    }
 }

function ad_imps_new(oid,ctoken) {
    createXmlHttpRequest();
	http_request.open('GET', 'ad_sys/ad_imps.php?oid='+oid+'&ctoken='+ctoken);
    http_request.send(null);
}