An organic thin film transistor having a semiconductor active layer containing a compound represented by the formula has a high carrier mobility and a small change in the threshold voltage after repeated operation. User utilities are functions of average rates of users, where different averaging rules can be used for different users. The mobile terminal having two state: a first state in which only the short sides are parallel with a horizontal surface and a second state in which only the long sides are parallel with the horizontal surface. In use, one end of the smokable rod is lit, and the tobacco cut filler of the inner core burns to yield tobacco smoke. An improved technique utilising a priori information is also described.