jquery 원활한 스크롤 업 구현 code_jquery

$ (함수(){
var $this = $(".renav");
var scrollTimer;
$this.hover(function(){
clearInterval(scrollTimer);
} ,function (){
scrollTimer = setInterval(function(){
scrollNews( $this );
}, 2000 )
}).trigger("mouseout"); );
function scrollNews(obj){
var $self = obj.find("ul:first")
var lineHeight = $self.find("li:first").height() ;
$self.animate({ "margin-top" : -lineHeight "px" },600 , function(){
$self.css({"margin-top":"0px"}). find( "li:first").appendTo($self)
})
}