function popup_main(URL) { 
	var re_size = (navigator.appVersion.indexOf("MSIE") != -1) ? "no" : "yes";
	var pos_x = ((screen.availWidth - 775)/2);
	var pos_y = ((screen.availHeight - 550)/2);
	var features = "width=775,height=550,scrollbars=no,resizable="+re_size+",top="+pos_y+",left="+pos_x;
	window.open(URL,"main",features); 
}

function popup_info(URL) { 
	var re_size = (navigator.appVersion.indexOf("MSIE") != -1) ? "no" : "yes";
	var pos_x = ((screen.availWidth - 725)/2);
	var pos_y = ((screen.availHeight - 425)/2);
	var features = "width=725,height=425,scrollbars=yes,resizable="+re_size+",top="+pos_y+",left="+pos_x;
	window.open(URL,"popup",features); 
}