var dwin
function popWindow(URL,W,H) {
  if (!dwin || dwin.closed){
   eval("dwin = window.open('" + URL + "','dwinbig','height="+ H +",width="+ W +",scrollbars=yes,resizable=yes')")
   }
  else{
	dwin.close();
    eval("dwin = window.open('" + URL + "','dwinbig','height="+ H +",width="+ W +",scrollbars=yes,resizable=yes')")
    dwin.focus()
  }  
}