function show_alert(str_alert){
		$('#result_box').show(); 
		$('#result_box').animate({opacity: 1}, 200, 'swing', function(){$('#result_box').html($('#result_box').html()+'<br>'+str_alert);});
		$('#result_box').delay(20000).animate({opacity: 0}, 2000, 'swing', function(){$('#result_box').html('');$('#result_box').hide()});
	}