function cshow(pn,pw,ph) {
  var aw = 12 ;
  var ah = 83 ;
  mw = screen.availWidth - aw ; 
  mh = screen.availHeight - ah ; 
  if( ph > mh ) {
    pw =  Math.round( mh * pw / ph ) ;
    ph = mh ;
  }
  if( pw > mw ) {
    ph =  Math.round( mw * ph / pw ) ;
    pw = mw ;
  }
	pl = Math.round( ( mw - pw - aw) / 2 ) ;
	pt = Math.round( ( mh - ph - ah) / 2 ) ;
  ph = ph + 25 ;
	pshow = window.open(pn, "ppwin", "toolbar=no,location=no,menubar=no,directories=no,status=no,scrollbars=no,resizable=yes,width="+pw+",height="+ph+",left="+pl+",top="+pt );
	if ( ( typeof(pshow) != "object" ) || !pshow || pshow.closed ) {
		return false;
	}
	else {
		pshow.window.focus();
	}
}