Abstract: A system and method for constructing a graphical user interface for an application being accessed by a user are provided. The method includes measuring the user's current work rate, deriving a threshold from the user's current work rate, determining the user's current activity within the application, assigning a value to the user's current activity, accessing a model for the application, the model defining links between activities within the application, assigning values to activities linked within the accessed model to the user's current activity, and displaying a control element in a graphical user interface for each activity with a value above the derived threshold.

Abstract: A system and method for constructing a graphical user interface for an application being accessed by a user are provided. The method includes measuring the user's current work rate, deriving a threshold from the user's current work rate, determining the user's current activity within the application, assigning a value to the user's current activity, accessing a model for the application, the model defining links between activities within the application, assigning values to activities linked within the accessed model to the user's current activity, and displaying a control element in a graphical user interface for each activity with a value above the derived threshold.

Abstract: A wheelchair suitable for invalids or geriatric patients has a chair or seat supported on independant forward and rearward castor frames pivotally connected together at a transverse axis to form a castor frame assembly. The chair is pivotally mounted on the forward and rearward castor frames so that in negotiating a step or other obstacle, the lifting movement of the occupant is divided into stages so that a pleasant or comfortable ride is obtained. The wheelchair may be folded into a collapsed condition with the chair itself located between the castor frames.