function tab_display_update(){
document.getElementById('update').style.display='block';
document.getElementById('notice').style.display='none';
document.getElementById('tab_update').style.backgroundImage='url("./picture/support/update.png")';
document.getElementById('tab_notice').style.backgroundImage='url("./picture/support/notice_.png")';
}
function tab_display_notice(){
document.getElementById('update').style.display='none';
document.getElementById('notice').style.display='block';
document.getElementById('tab_update').style.backgroundImage='url("./picture/support/update_.png")';
document.getElementById('tab_notice').style.backgroundImage='url("./picture/support/notice.png")';
}