function show_gmap(wintype) {
 var nwl = (screen.width-800)/2;
 var nwh = (screen.height-630)/2;
        
 popUp=window.open(wintype,'NewWindows', 'toolbar=no, location=no, directories=no, status=no, menubar=no,  scrollbars=yes, resizable=yes, width=800, height=630, left='+nwl+', top='+nwh+'');
 popUp.window.focus();
}