## 5 Results  
We present the results of two case studies (Sections 4.5.1 and 4.5.2), each applying different management approaches to assess the flexibility and effectiveness of the systems in allowing or preventing modifications to the emergency pedal icon by the driver, [PERSON]. The two approaches tested our Onto-CMS and a system that does not rely on ontologies but uses fixed rules.  
In the first case study (Section 4.5.1), the focus is on managing critical customisations to prevent accidents in the DVI. Onto-CMS ensures the immutability of a standardised element, such as the emergency pedal icon, preventing its removal from the display. The goal is that [PERSON] should not be able to remove or change the emergency pedal icon, to have it always in view for safety reasons. Both systems reach this aim efficiently but following different approaches. Our system uses an ontological structure to manage driver characteristics and preferences, thus providing a solution that is both dynamic and adaptive. If [PERSON]'s condition improves in the future, the system could automatically change without manual intervention. This system has flexibility in respect to changing relationships between the driver's characteristics and modification restrictions. The non-ontology-based system, however, uses fixed logic in an application to prevent modifications. Although it would be able to prevent [PERSON] from changing the icon, too, if [PERSON]'s condition changes, it would need a manual update. That structure leads to slower response times, as it requires manual updates each time a change is needed. Therefore, Onto-CMS adapts to the user's preferences while also respecting the unmodifiable nature of standardised safety elements.  
The second case study (Section 4.5.2) deals with the adaptation of the emergency pedal icon to enhance safety features. This case study demonstrates how the Onto-CMS can adaptively adjust the standardisation level of the interface, allowing [PERSON] to modify the icon itself to improve visibility and accessibility without compromising safety. This ontology-driven system, thus dynamic, supports modification and reacts to [PERSON]'s needs. The system detects the sensory impairments listed in [PERSON]'s profile and applies necessary restrictions to ensure that modifications do not compromise safety. The Onto-CMS allows [PERSON] to enlarge the icon and adjust the contrast according to her requirements. Indeed, the ontology's flexible structure allows the system to adjust dynamically to both temporary changes and evolving conditions in [PERSON]'s needs.  
Contrary to this, the conventional system cannot allow for the change immediately due to the rigid rules involved. Circumstances change, and the particular needs of [PERSON] may also change due to her fluctuating abilities over time. This lack of dynamic adaptation limits the system from revising the emergency pedal icon in extreme situations.  
Therefore, the ontology-based system has significant advantages in adaptability and responsiveness. It enables runtime adaptations depending on the driver's needs and external conditions, whereas the other system remains static and requires updating manually.