public function checkUser($userName, $conferenceId) {
$userTrainingModel = new Model_UserInTraining();
$userTrainingData = $userTrainingModel->findByIdTraining($conferenceId);
$userModel = new Model_User();
$userData = $userModel->findByUsername($userName);
$userId = $userData['id'];
foreach ($userTrainingData as $key => $value){
if ($value['user_id'] == $userId)
{
return TRUE;
}
}
return FALSE;
}