var simWindow = null;
    function openSimWindow() {
        if (simWindow == null || simWindow.closed) {
            simWindow = window.open('https://sim.therapservices.net/sim/SIMClient.html', 'simPopup',
                'resizable=0,scrollbars=0,status=0,width=495,height=460');
        }
        simWindow.focus();
        return false;
    }