var popUpWin=0;
var left = (screen.width - 100) / 2;
var top = (screen.height - 100) / 2;

function popUpWindow(URLStr)
{
  if(popUpWin)
  {
    if(!popUpWin.closed) popUpWin.close();
  }
  popUpWin = 
  	window.open(URLStr, "popUpWin", "toolbar=no,location=no,directories=no,status=no,menubar=no," +
  		"scrollbar=no,resizable=yes,copyhistory=no," +
		"width=200,height=200,left="+left+",top="+top+",screenX="+left+",screenY="+top);
}

function popUpWindowFixSize(URLStr, width, height)
{
  if(popUpWin)
  {
    if(!popUpWin.closed) popUpWin.close();
  }
  left = (screen.width - width) / 2;
  top = (screen.height - height) / 2;
  popUpWin = 
  	open(URLStr, "popUpWin", "toolbar=no,location=no,directories=no,status=no,menubar=no," +
  		"scrollbar=no,resizable=no,copyhistory=no," +
		"width=" + width + ",height=" + height + ",left="+left+",top="+top+",screenX="+left+",screenY="+top);
}