function openWindow(url, name, w_width, w_height)
{
var w_left = (screen.width > w_width) ? (screen.width - w_width) / 2 : 0;
var w_top = (screen.height > w_height) ? (screen.height - w_height) / 2: 0;
popupWin = window.open(url,name, "toolbar=0,location=0,directories=0,menuBar=0,scrollbars=0,resizable=0,address=0,width=" + w_width + ",height=" + w_height + ",left=" + w_left + ", top=" + w_top)
}