var $timeStamp = new Date().getTime();
$page.on( 'mousewheel', function( $event, $delta ) {
var timeNow = new Date().getTime();
$event.preventDefault();
if ( timeNow - $timeStamp < 50 ) {
$timeStamp = timeNow;
} else if ( $event.deltaY < 0 ) {
$timeStamp = timeNow;
$page.trigger( 'swipeup' );
} else if ( $event.deltaY > 0 ) {
$timeStamp = timeNow;
$page.trigger( 'swipedown' );
}
});