var popUpWin=0; 

function popUpCentro(URLStr, Nome, width, height) 
{ 
  if(popUpWin) 
    { if(!popUpWin.closed) popUpWin.close(); } 
  var left = (screen.width - width) / 2;
  var top = (screen.height - height) / 2;
  popUpWin = open(URLStr, Nome, 
    'toolbar=no,location=no,directories=no,status=no,menub ar=no,scrollbar=no,resizable=no,copyhistory=yes,width='+
	width+',height='+height+',left='+left+',top='+top+',screenX='+left+',screenY='+top+''); 
} 

function popUpWindow(URLStr, left, top, width, height) 
{ 
  if(popUpWin) 
  { if(!popUpWin.closed) popUpWin.close(); } 
  popUpWin = open(URLStr, 
    'popUpWin', 'toolbar=no,location=no,directories=no,status=no,menub ar=no,scrollbar=no,resizable=no,copyhistory=yes,width='+
	 width+',height='+height+',left='+left+', top='+top+',screenX='+left+',screenY='+top+''); 
}