//********** global window handles ***********************************************************************************************************************************************
	var priv = 0,				// privacy assured window
		news_rep = 0,			// newsletter reply
		links_rep = 0,		// links reply
		schedule = 0,			// schedule window
		mem_terms = 0,			// fitness centre T & C's
		rooms = 0,				// conference & exhibition room dimensions and capacities
		pic1 = 0,					// picture window 1
		pic2 = 0,					// picture window 2
		pic3 = 0,					// picture window 3
		pic4 = 0,					// picture window 4
		pic5 = 0,					// picture window 5
		pic6 = 0,					// picture window 6
		pic7 = 0,					// picture window 7
		pic8 = 0,					// picture window 8
		pic9 = 0,					// picture window 9
		pic10 = 0,				// picture window 10
		pic11 = 0,				// picture window 11
		pic12 = 0;				// picture window 12
//********************************************************************************************************************************************************************************
//********** open_window *********************************************************************************************************************************************************
function open_win (ptr, win_name, ht, wth, url, x, y, mbar, rsize, scroll, ttbar, tlbar)
{
	var f = 1, opt;

	// note: if x = -1, y = -1 then put window in centre of screen

	// if exit window already open, set flag so it isn't opened again
	if (ptr)
	{
		f = ptr.closed;
	}

	// if window not open then open
	if (f)
	{
		// calculate screen centre x, y position - if required
		if (x == - 1)
		{
			x = Math.floor (document.body.offsetWidth / 2) - Math.floor (wth / 2);
			if (x < 0) x = 0;
		}
		if (y == -1)
		{
			y = Math.floor (document.body.offsetHeight / 2) - Math.floor (ht / 2);
			if (y < 0) y = 0;
		}

		// set up window options
 		opt = "alwaysRaised=yes,hotkeys=no,location=no,menubar=" + mbar + ",resizable=" + rsize + ",scrollbars=" + scroll + ",titlebar=" + ttbar + ",toolbar=" + tlbar + ",width=" + wth + ",height=" + ht + ",screenX=" + x + ",screenY=" + y;

		// open window
		ptr = window.open ("", win_name, opt);

		// move widow to cover centre of screen
		ptr.moveTo (x, y);

		// load window with url if required (this done after window positioned as it will not postion until url is fully loaded if url loaded first)!!!!
		if (url.length)
		{
			ptr.location.href = url;
		}
	}

	// return window pointer value
	return ptr;
}
//********************************************************************************************************************************************************************************