function zentriert()
{
var iMyWidth;
var iMyHeight;
iMyWidth = (window.screen.width/2) - (250 + 10)
iMyHeight = (window.screen.height/2) - (300 + 50)
var win2 = window.open("../kohchangkarten/kohchangkarte.htm","Fenster2","status,height=600,width=500,resizable=no,left=" + iMyWidth + ",top=" + iMyHeight + ",screenX=" + iMyWidth + ",screenY=" + iMyHeight + ",scrollbars=no")
}