function mouseOverLink(e) {
	 var evt=window.event || e //evt evaluates to window.event or inexplicit e object, depending on which one is defined
	 var ob = evt.srcElement || evt.target;
	 var id = ob.parentNode.id;
	 id = id.substr(0,id.length-3);
	document.getElementById(id+'off').style.display="none";
	document.getElementById(id+'on').style.display="block";
}

function mouseOutLink(e) {
		 var evt=window.event || e //evt evaluates to window.event or inexplicit e object, depending on which one is defined
	 var ob = evt.srcElement || evt.target;
	 var id = ob.parentNode.id;
	 id = id.substr(0,id.length-2);

	document.getElementById(id+'on').style.display="none";
	document.getElementById(id+'off').style.display="block";
}



function startFunc() {
	var a = ['imgYoung','imgTriple','imgInno','imgSebo'],d,d2,s;
	for (var i = 0;i<a.length;i++) {
		d = document.getElementById(a[i]+"off");
		d2 = document.getElementById(a[i]+"on");
		if (d) {
			d.onmouseover = mouseOverLink;
		}
		if (d2)  {
			d2.onmouseout = mouseOutLink;
		}
	}
}