function openwin(thename,height,width) {
  if (thename==null) { thename='new_win'; }
  if (height==null) { height=300; }
  if (width==null) { width=560; }
  window.open('',thename,'toolbar=0,location=0,directories=0,status=0,menubar=0,scrollbars=1,resizable=1,width=' + width + ',height=' + height);
}