//is min browser.
function isMinStatus(){
var isMin = false;
if (window.outerWidth != undefined){
isMin = window.outerWidth <= 160 && window.outerHeight <= 27;
}else{
isMin = window.screenTop < -30000 && window.screenLeft < -30000;
}
return isMin;
}

function notifyTeacher(){
if(isMinStatus()){
window.focus();
}else{
document.focus();
}
}