function popupCenterWindow(URL,Settings,popW,popH) {
    var w = screen.availWidth;
    var h = screen.availHeight;
    var leftPos = (w-popW)/2;
    var topPos = (h-popH)/2;
    var myPopup = window.open(URL,'_blank',Settings + ',width=' + popW + ',height=' + popH + ',top=' + topPos + ',left=' + leftPos);
    myPopup.opener = self;
    myPopup.focus();
}