function popupWindow(address, width, height) {
   var w = width;
   var h = height;
   var l = Math.floor((screen.width-w)/2);
   var t = Math.floor((screen.height-h)/2);
   window.open(address,"","width=" + w + ",height=" + h + ",top=" + t + ",left=" + l +",resizable=no, location=no");
}