function open_win(my_winname,my_url,my_width,my_height) {
  if (!my_winname) {
  	my_winname = "_new";
  }
  newwindow=window.open(my_url,my_winname,'scrollbars,width='+my_width+',height='+my_height+',screenX=0,screenY=0,left=0,top=0, resizable')
	newwindow.focus();
}