function random_img(){
  var headerimg=new Array()
	headerimg[1]="images/top_bg1.jpg"
	headerimg[2]="images/top_bg2.jpg"
	headerimg[3]="images/top_bg3.jpg"
	headerimg[4]="images/top_bg4.jpg"
	headerimg[5]="images/top_bg5.jpg"
	headerimg[6]="images/top_bg6.jpg"
	headerimg[7]="images/top_bg7.jpg"
	headerimg[8]="images/top_bg8.jpg"
	headerimg[9]="images/top_bg9.jpg"
	headerimg[10]="images/top_bg10.jpg"
	headerimg[11]="images/top_bg11.jpg"
	headerimg[12]="images/top_bg12.jpg"
	headerimg[13]="images/top_bg13.jpg"
	headerimg[14]="images/top_bg14.jpg"
  var ry=Math.floor(Math.random()*headerimg.length)
  if (ry==0)
     ry=1
     document.write('<img src="'+headerimg[ry]+'" border=0 >')
}