function setNav(num){
					var url=["http://www.yunjiaoyu.com","index.asp"];
					var image="";
					var img="image/b_";
					var NT=2;
					for(i=1;i<=NT;i++){
						if(i==num){
						image+="<a href='"+url[i-1]+"'><img src='"+img+i+"_on.gif' id='nav_"+i+"' name='"+i+"' border='0' /></a>";
						}else{
						image+="<a href='"+url[i-1]+"'><img src='"+img+i+".gif' id='nav_"+i+"' name='"+i+"'  border='0' /></a>";	
						}
					}
					document.write(image);
					for(i=1;i<=NT;i++){
						//document.getElementById("nav_"+i).name=i;
						if(i!=num){
						document.getElementById("nav_"+i).onmouseover=function(){document.getElementById("nav_"+this.name).src=img+this.name+"_on.gif";}
						document.getElementById("nav_"+i).onmouseout=function(){document.getElementById("nav_"+this.name).src=img+this.name+".gif";}
						}
					}
					}