function popUpWindow1(URLstring) {
var popW = 320;
var popH = 300;
var popUpWin=0;
var w = screen.width;
var h = screen.height;
var leftPos = (w-popW)/2, topPos = (h-popH)/2;
  if(popUpWin)  {
    if(!popUpWin.closed) popUpWin.close();
	}
var attributes="toolbar=no,status=no,menubar=no,scrollbars=no,resizable=no,copyhistory=yes,width="+popW+",height="+popH+",top="+topPos+",left="+leftPos;
popUpWin = window.open(URLstring,"popUpWin",attributes);
popUpWin.focus();
}