$(document).ready(function(){
	var today = new DateFormat('toyyyyMMdd').format(new Date());
	$('#study li[class]').each(function () {
		var li = $(this);
		var limitDate = li.attr('class');
		if (limitDate.match(/^to[0-9]{4}[0-9]{2}[0-9]{2}$/)) {
			var state = $();
			if (limitDate < today) {
				li.remove();
			}
		}
	});
});