function newImage(arg) {
	if (document.images) {
		rslt = new Image();
		rslt.src = arg;
		return rslt;
	}
}

function changeImages() {
	clearInterval(timer);

	if (document.images && (preloadFlag == true)) {
		for (var i=0; i<changeImages.arguments.length; i+=2) {
			document[changeImages.arguments[i]].src = changeImages.arguments[i+1];
		}
	}
}

var preloadFlag = false;
function preloadImages() {
	if (document.images) {
		navtech_over = newImage("images/navtech-over.gif");
		navpartf_over = newImage("images/navpartf-over.gif");
		navhumidity_over = newImage("images/navhumidity-over.gif");
		navabout_over = newImage("images/navabout-over.gif");
		navcontact_over = newImage("images/navcontact-over.gif");
		navhome_over = newImage("images/navhome-over.gif");
		subnav_01_over = newImage("images/subnav_01-over.gif");
		subnav_02_over = newImage("images/subnav_02-over.gif");
		subnav_03_over = newImage("images/subnav_03-over.gif");
		preloadFlag = true;
	}
}

var timer;
function subnavClear(){
	timer=setInterval("subnavSet('none')",500);
}

function subnavSet(val){
	clearInterval(timer);
	var nav = document.getElementById("Table_01");
	nav.style.display=val;
	var state = nav.style.display;
}
function subnavSwitch(){
	var nav = document.getElementById("Table_01");
	nav.style.display=val;
	var state = nav.style.display;
	if (state=='none'){
		nav.style.display='block';
	}else{nav.style.display='none';}
}