var popupPosition = {left: parseInt(window.screen.availWidth / 3), top: parseInt(window.screen.availHeight / 3)};		
<!-- 
function openwin(purl) 
{ 
	window.open('http://'+purl, 'mywindow','toolbar=yes, location=yes,directories=yes,status=yes,menubar=yes,scrollbars=yes,copyhistory=yes, resizable=yes'); 
} 
function openpop(purl) 
{ 
	window.open(purl, 'popup', 'location=0,status=0,scrollbars=0,resizable=0,width=350,height=250,top=' + popupPosition.top + ',left=' + popupPosition.left).focus();
} 
function openpop(purl,pW,pH) 
{ 
	if (pW=="")
	{
	pW = 200;
	}
	if (pH=="")
	{
	pH = 200;
	}
	window.open(purl, 'popup', 'location=0,status=0,scrollbars=0,resizable=0,width='+pW+',height='+pH+',top=' + popupPosition.top + ',left=' + popupPosition.left).focus();
} 
function OpenBrWindow(theURL,winName,features, myWidth, myHeight, isCenter) { //v3.0
if(window.screen)if(isCenter)if(isCenter=="true"){
var myLeft = (screen.width-myWidth)/2;
var myTop = (screen.height-myHeight)/2;
features+=(features!='')?',':'';
features+=',left='+myLeft+',top='+myTop;
}
window.open(theURL,winName,features+((features!='')?',':'')+'width='+myWidth+',height='+myHeight);
}