function showLayer(name){
 var layer = document.getElementById(name);
 var tags = document.getElementsByTagName('div');
 for(var i=0; i<tags.length; i++){
 	var tagName = tags[i].id;
 	if(tagName.substr(0,1) == "_"){
		if(tagName == name){
			layer.style.display = "block";
		}
		else{
			document.getElementById(tagName).style.display = "none";
		}
	}
 }
}