function randomImage() {
var now=new Date();
var modulus=(now.getSeconds()%6);    // 8 images from 00 to 04
if (modulus == 0) {
        var section = "protection";
  } 
if (modulus == 1) {
        var section = "vehicles2";
  }
if (modulus == 2) {
        var section = "decontamination4";
  }
if (modulus == 3) {
        var section = "explosive";
  }
if (modulus == 4) {
        var section = "vehicles";
  }
if (modulus == 5) {
        var section = "vehicles2";
}
if (document.images) {
    side_image = new Image;
    side_image.src = "img/side_" + section + ".jpg";
    document.images["side"].src = side_image.src;
  }
}