function open_carnet(url) {    var ah = screen.availHeight;    var aw = screen.availWidth; var height = 600; var width =  400; var str = "scrollbars=no,resizable=no,menubar=no,status=no," +"height=" + height + ",innerHeight=" + height;   str += ",width=" + width + ",innerWidth=" + width;    var xc = 400;    var yc = (ah - height) / 2;    str += ",left=" + xc + ",screenX=" + xc;    str += ",top=" + yc + ",screenY=" + yc; window.open(url, 'new4', str); }// JavaScript Document