function openNewWindow(url,title,w,h) {
  var int_windowLeft = (screen.width - w) / 2;
  var int_windowTop = (screen.height - h) / 2;
  var str_windowProperties = 'height=' + h + ',width=' + w + ',top=' + int_windowTop + ',left=' + int_windowLeft + ',resizable=false';
  popupWin = window.open(url,title,str_windowProperties);
}