Research On Perceptual-Control-Based Task Analysis Model

For a long time, it has been a difficult task to develop a user interface which is effective and friendly to use for interactive systems. It needs a variety of models to help developers design and implement a user interface. Nowadays, a user centered design aims to provide support for the user's task.So it is particularly important to understand and model the user's task, and to guide and implement the user interface. However, the traditional task analysis models and methods are not only difficult to characterize the nature of user action in dynamic and open environment, but also difficult to describe the target for user, which affects the availability of user interface. These user interfaces can't meet the needs of users and tasks.The operating environment of software system has the characteristics of diversity, which makes the users in a dynamic and open environment when they use the system. At present, most of the task analysis models and methods for user interface design adopt the view that the system is easy to be implemented, and use the concept of technology environment to describe the interaction between users and system. These models view the task as a sequence of operations.They think that the operation process users use the system to complete the task is immutable without outside influence. Among them, the structural task analysis models mainly consider how to achieve the goal. But, they ignore the environmental factors. Functional task analysis models consider the user's behavior.But they ignore the user's target, which doesn't make the design of the user interface meet the needs of users very well. However, the theory of perception controlnot only models the influence of the external environment, from the point of psychology's view to describe the dynamic and open environment, but also considers the user's goal.This theory provides a feasible solution for the problem described above.In the era of mobile equipment technology and the diversity of using environment, a task analysis model based on the perceptual control theory is proposed.Its purpose is to explore an enhanced user interface usability task modeling methods and support for developing a highly user interface tool. Compared with the existing task analysis models, the model which is proposed in this paper will bring the perception control theory, which is based on the user centric view and improves the system availability. With the characteristics of the theory, this paper extends and improves the use case analysis method, and defines the concept of use case with goal which is called GUC, and finally establishes a structured task analysis model based on the perceptual control theory. Finally, in order to verify the validity of the model, this paper will design a preliminary forecast user interface and make the necessary evaluation of the interface according to the method of task weather forecasting system analysis modeling.