function popUp(url,name,x,y){

		var string;

		// combine the window properties into one line (var string)
		string =  "toolbar=0,location=0,directories=0,status=0,menubar=0,scrollbars=0,resizable=0,resizable=no, copyhistory=0,";
		string += ",width=";
		string += x;
		string += ",height=";
		string += y;
	
		if (name == "intro"){
		
		// function to center main window
		centerWindow=window.open(url,name,string);
		
		// center the window according to the top left corner of the popup window
		width=(screen.width / 2) - 200;
		height=(screen.height / 2) - 200;
	
		centerWindow.window.moveTo(width,height);
	}
	
	else {window.open(url,name,string);}
}

function popUpSB(url,name,x,y){

		var string;

		// combine the window properties into one line (var string)
		string =  "toolbar=0,location=0,directories=0,status=0,menubar=0,scrollbars=1,resizable=0,resizable=no, copyhistory=0,";
		string += ",width=";
		string += x;
		string += ",height=";
		string += y;
	
		if (name == "intro"){
		
		// function to center main window
		centerWindow=window.open(url,name,string);
		
		// center the window according to the top left corner of the popup window
		width=(screen.width / 2) - 200;
		height=(screen.height / 2) - 200;
	
		centerWindow.window.moveTo(width,height);
	}
	
	else {window.open(url,name,string);}
}