fire onchange event of dropdownlist on page load

Question

Hi...
   I have create view in asp.net mvc4.

In my view there is one dropdown:
 @Html.DropDownList("Type", new SelectList(TypeList, "value", "text"), new { id = "ddl1", onchange = "SelectedIndexChanged()" })

In javascript:

   <script type="text/javascript">

        function SelectedIndexChanged() {

            var value = $("#ddl1").val();

            alert(value);

            if (value == "type1")

            {

                document.getElementById('tblsat').style.visibility = "visible";

                document.getElementById('tblSuper').style.visibility = "hidden";

            }

            else

            {

                document.getElementById('tblSuper').style.visibility = "visible";

                document.getElementById('tblsat').style.visibility = "hidden";

            }

        }

    </script>
    At runtime if i change dropdown selection onchange event will work fine..But i want to fire onchange event on page load also.

   Thanks..