function showpopup(url,window_name){
  win=open(url, window_name, 'toolbar=no,scrollbars=yes,statusbar=no,resizable=no,resize=no,locationbar=no,menubar=no,personalbar=no,titlebar=no,width=740,height=550,top=0,left=0,screenX=0,screenY=0,alwaysRaised');
  win.focus();
}