function OpenWin(URL,w,h,Nom) { 
var winW = (screen.width - w) / 2;
var winH = (screen.height - h) / 2;
var windowprops ="top=" + winH + ",left=" + winW + ",toolbar=no,location=no,status=no, menubar=no,scrollbars=no, resizable=no,width=" + w + ",height=" + h;
window.open(URL,Nom,windowprops);}