function toggle_image(imgname, state)
{
    image = document.getElementById(imgname);
    imgprefix = (state == 1) ? "-on" : "-off";

    image.src = "images/" + imgname + imgprefix + ".jpg"
}

function go (page)
{
    location.href = page;
    return true;
}

function go_nw(page)
{
    window.open (page);
    return true;

}