function openwin (url, size) {
	switch (size) {
		case 1:
			sizes = 'width=480px,height=600px';
			break;
		case 2:
			sizes = 'width=720px,height=450px';
			break;
		case 3:
			sizes = 'width=540px,height=510px';
			break;
		default:
			sizes = '';
	}
	win = window.open (url, '_blank', sizes);
	win.focus ();
}