function newpage(page_url) {
var choose = eval(document.forms[0].pdmenu.selectedIndex);
var target_link = "";
		if (page_url==null) {
        	target_link = document.location.pathname+"?series=" + document.forms[0].pdmenu.options[choose].value;
		} else {
        	target_link = page_url +"?series=" + document.forms[0].pdmenu.options[choose].value + "&charset=" + document.forms[0].charset.value;
		}
        location=target_link;
}