<!--
var lastScrollX = 0;
var lastScrollY = 0;
function heartBeat() {
  var leftD = document.getElementById("left_ad");//显示在左边的声明对象
  var rightD = document.getElementById("right_ad");//显示在右边的声明对象
  var diffY = 0;
  var diffX = 0;
  if (typeof window.pageYOffset != 'undefined') {
    diffY = window.pageYOffset;
    diffX = window.pageXOffset;
  }
  else if (typeof document.compatMode != 'undefined'&& document.compatMode != 'BackCompat') {
    diffY = document.documentElement.scrollTop;
    diffX = document.documentElement.scrollLeft;
  }
  else {
    diffY = document.body.scrollTop;
    diffX = document.body.scrollLeft;
  }    

  if (diffY != lastScrollY) {
    percent = 0.1 * (diffY - lastScrollY);
    if (percent > 0) percent = Math.ceil(percent);
    else percent = Math.floor(percent);

    if (leftD) leftD.style.pixelTop += percent;//在左边显示
    if (rightD) rightD.style.pixelTop += percent;//在右边显示
    lastScrollY = lastScrollY + percent;
  }

  if (diffX != lastScrollX) {
    percent = .1 * (diffX - lastScrollX);
    if (percent > 0)
      percent = Math.ceil(percent);
    else
      percent = Math.floor(percent);
    if (leftD) leftD.style.pixelLeft += percent;//显示在左边
    if (rightD) rightD.style.pixelLeft += percent;//显示在右边
    lastScrollX = lastScrollX + percent;
  }
}

window.setInterval("heartBeat()", 120);
//-->