function KW_autoClear(obj,def){
	if (obj.value==def) obj.value=""
}

function getLong(){
long=document.getElementById("center").offsetHeight;
return long;
}

function setLong(){

if(document.getElementById("tr_mid")){
	long=getLong();

	if(long<450){
	long=450;
	}
	else{
	long+=20;
	}

	document.getElementById("tr_mid").style.height =  long + "px";
}
}