function preload() {
	var header_top = new Image();
	var btn_home2 = new Image();
	var btn_operation2 = new Image();
	var btn_about2 = new Image();
	var btn_vessels2 = new Image();
	var btn_contact2 = new Image();
	header_top.src = "images/header_top.png";
	btn_home2.src = "images/btn_home2.gif";
	btn_operation2.src = "images/btn_operation2.png";
	btn_about2.src = "images/btn_about2.png";
	btn_vessels2.src = "images/btn_vessels2.png";
	btn_contact2.src = "images/btn_contact2.png";
}

function MM_openBrWindow(theURL,winName,features) {
	window.open(theURL,winName,features);
}

function show_bs(div,x,y) {

	var ua = navigator.userAgent;

	if (ua.match(/Opera[\/\s](\d\.\d+)/)) {
		document.getElementById(div).style.left=x;
		document.getElementById(div).style.top=y;
		document.getElementById(div).style.visibility="visible";
	}
	else if (ua.match(/MSIE (\d\.\d+)/)) {
		document.all(div).style.left=x;
		document.all(div).style.top=y;
		document.all(div).style.visibility="visible";
	}
	else if (ua.match(/Mozilla\/(4\.[5678]\d?)/)) {
		document.write("Netscape Communicator " + RegExp.$1);
	}
	else if (ua.match(/Netscape6?\/([\.\d]+)/)) {

	}
	else if (ua.match(/Safari\/([\.\d]+)/)) {
		document.getElementById(div).style.left=x;
		document.getElementById(div).style.top=y;
		document.getElementById(div).style.visibility="visible";
	}
	else if (ua.match(/Gecko/)) {
		if (ua.match(/(Firebird|Firefox)\/([\.\d]+)/)) {
			document.getElementById(div).style.left= x + "px";
			document.getElementById(div).style.top= y + "px";
			document.getElementById(div).style.visibility="visible";
		}
		else if (ua.match(/Thunderbird\/([\.\d]+)/)) {
			document.write("Mozilla Thunderbird " + RegExp.$1);
		}
		else if (ua.match(/rv:([\.\d]+)/)) {
			document.write("Mozilla " + RegExp.$1);
		}
		else {
			document.write("Mozilla");
		}
	}
	else {
		document.write("N/A");
	}
}
function hide_bs(div) {
	document.getElementById(div).style.visibility="hidden";
}