public static function isValidTime($h,$m,$s,$hs24=true)
	{
		if($hs24 && ($h < 0 || $h > 23) || !$hs24 && ($h < 1 || $h > 12)) return false;
		if($m > 59 || $m < 0) return false;
		if($s > 59 || $s < 0) return false;
		return true;
	}