This is the preliminary work on rec

This is the preliminary work on recognizing complexactivities, such as smoking, drinking coffee, giving a talk, andeating. We intend to further explore these activities in morerealistic scenarios. For example, smoking combined with otheractivities, and eating in a group. Moreover, we would like toconsider more complex activities, where hand movements areinvolved. We will further explore the personalized classifica-tion for these complex activities for individual users. In thiswork, we have imbalanced classes for some activities, so weintend to collect more data on these activities to create a datasetwith balanced class distribution