function popWin(url,c,d) {
    
    var a=screen.availWidth/2 - c/2;
    var b=screen.availHeight/2 - d/2;
    var win = window.open(url,"popwin","width="+c+",height="+d+",dependent=1,hotkey=1,directories=0,location=0,status=0,menubar=0,resizable=0,scrollbars=0,left="+a+",top="+b); 
    if( window.focus ) { win.focus(); }
}