function hi(n) {
  img1=eval("document.all.img_left_"+n);
  img2=eval("document.all.img_right_"+n);
  td=eval("document.all.upper_td_"+n);
  img1.src="img/h_upperleft.gif";
  img2.src="img/h_upperright.gif";
  td.style.backgroundImage="url(img/h_upperbg.gif)";
}
function ou(n) {
  img1=eval("document.all.img_left_"+n);
  img2=eval("document.all.img_right_"+n);
  td=eval("document.all.upper_td_"+n);
  img1.src="img/upperleft.gif";
  img2.src="img/upperright.gif";
  td.style.backgroundImage="url(img/upperbg.gif)";
}