var SEASON_OBJ = { 
"top_bk":[
	"top_bk_winter13.jpg",
	"top_bk_winter15.jpg",
	"top_bk_newyear06.jpg",
	"top_bk_holiday10.jpg",
]};

function DispTOP_bk()
{
	var msg ;
	var _No = Math.floor( Math.random() * SEASON_OBJ.top_bk.length ) ;
	var _Fname = SEASON_OBJ.top_bk[ _No ] ;
	if( ! _Fname) _Fname = 'top_bk_basic.jpg' ; // for IE
	msg ='<img src="E/img/seasonON/' + _Fname + '" border="0" alt="Discount Tickets from US to Japan. 24/7 Online Booking!" hspace="0" usemap="#m_top_bk">';
	document.write(msg);
}