PITA：一种面向任务的结构模型

In order to improve the efficiency of human-computer interaction in a complex man-machine interactive environment.The paper analysed the implementation process of the user behaviors in-depth during the human-computer interaction process and put forward the concept of the task and establish the task-oriented human-computer interaction model PITA. The model can effectively manage tasks creation, implementation and completion through task management module, provides a unified interface for the application layer to overcome the task management chaotic shortcoming in the complex human-computer interaction environments. Practice shows that the model can effectively improve the efficiency of human-computer interaction.