var today = new Date();
var upday = new Date();

function koushin(y, m, d) {
   upday.setFullYear(y);
   m = m - 1;
   upday.setMonth(m);
   upday.setDate(d);
   difference = today.getTime() - upday.getTime();
   keika = Math.floor(difference / (1000 * 60 * 60 * 24));
   if (keika < 3) {
      document.write("<img src='/tufs_common/images/common/icon_new.gif' height='15' width='20' alt='NEW'>");
   }
}