function popUp(url, name, w, h) {
    var winl = (screen.width - w) / 2;
    var wint = (screen.height - h) / 2;
    winprops = 'height='+h+',width='+w+',top='+wint+',left='+winl+',scrollbars=yes,resizable=yes';
    win = window.open(url, name, winprops);
    win.focus();
    }