function nokno(stranka, jmeno, sb, h, w)
{
var levo = screen.width;
var vrch = screen.height;

levo = (levo / 2) - (w / 2);
vrch = (vrch / 2) - 200;
winprops = 'height='+h+',width='+w+',scrollbars='+sb+',top='+vrch+',left='+levo+',resizable';

win = window.open(stranka, jmeno, winprops);
}