function popup(popupUrl, width, height) {
	if (width == null || width == "") {
		width = 400;
	}
	if (height == null || height == "") {
		height = 300;
	}
	var left = (window.screen.width - width) / 2;
	var top = (window.screen.height - height) * 0.4;
	window.open(popupUrl, "", "width=" + width + ",height=" + height + ",left=" + left + ",top=" + top + ",fullscreen=no,toolbar=no,menubar=no,scrollbars=no,resizable=no");
}