7 Conclusion and Future Works
This paper has discussed the design of Wearable Expert Systems. The proposed design methodology is KAFKA, a framework based on the Knowledge Artifact conceptual model, which is general enough to be adopted in different contexts and programming paradigms.
From the conceptual point of view, KAFKA aims at making the development of knowledge-based systems (in particular, rule-based systems) quicker and simpler through the reduction of knowledge engineer responsibilities. In this way, the knowledge engineering process is focused on the kinds of knowledge involved in the decision making activity rather than on how to model it, representing a radical change of perspective if compared with classical approaches like CommonKADS and MIKE. In this sense, KAFKA philosophy is closer to methodologies like MOKA (Stokes et al., 2001) and KNOMAD (Curran et al., 2010), proposed in the knowledge-based engineering field as product-oriented (Verhagen et al., 2012) rather than process-oriented tools for supporting users in the configuration of objects.
The WESs which can be developed employing this methodology bear some distinguishing features with respect to traditional expert systems. The WES knowledge base may change dynamically, following the long-term evolution of the monitored system and of its surrounding environment. Moreover, the presence of a centralized knowledge maintenance system, in principle common to a large number of WES instances, permits to exploit the massive amount of information coming from this large set of wearable devices: for instance, in the example of section 5, the Queue status may be monitored reliably by collecting data from all the application users in the city, tens or maybe hundreds of devices.