function if_change(){
 		var category;
		category = document.chane_iframe_disp.category1.value + document.chane_iframe_disp.category2.value;
		//alert(category);
		//alert(document.chane_iframe_disp.reset.value);
		if(category.match("all") ){
			bboad.location.href = "bulletin_board/comu.php";
		}else{
			bboad.location.href = "bulletin_board/comu.php?cat="+category;
		}
		

	}