Overview
The Context Toolkit aims at facilitating the development and deployment
of context-aware applications.
By context, we mean environmental information that is part of
an application's operating environment and that can be sensed by the application.
The Context Toolkit consists of context widgets and a distributed infrastructure
that hosts the widgets. Context widgets are software components
that provide applications with access to context information while hiding
the details of context sensing.
In the same way GUI widgets insulate applications from some presentation
concerns, context widgets insulate applications from context acquisition
concerns.
To summarize, the services of the Context Toolkit are:
encapsulation of sensors
access to context data through a network API
abstraction of context data through interpreters
sharing of context data through a distributed infrastructure
storage of context data, including history
basic access control for privacy protection
A context adaptive system typically enables the user to maintain a certain application (in different forms) while roaming between different wireless access technologies, locations, devices and even simultaneously executing everyday tasks like meetings, driving a car etc. For example a context adaptive and hence ubiquitous navigation system would offer navigation support in the situations at home, indoor, outdoor, and in car. This involves making the navigation functionality available for different availability of output devices, input devices and location sensors as well as adapting the user interaction operability to the current speed, noise or operator handicaps while keeping in mind the overall applicability depending on the user preferences, his knowledge, current task etc.[1]
Kontextadaption ist ein Begriff aus der Softwaretechnik, der verwendet wird, um technische Systeme zu bezeichnen, die ihre Struktur, Funktionalität oder Verhalten zur Laufzeit ändern können, um sich an unterschiedliche Umgebungsgegebenheiten zu richten.
Context-aware computing refers to a general class of mobile systems that can sense their physical environment, i.e., their context of use, and adapt their behavior accordingly. Such systems are a component of a ubiquitous computing or pervasive computing environment. Three important aspects of context are: (1) where you are; (2) who you are with; and (3) what resources are nearby. Although location is a primary capability, location-aware does not necessarily capture things of interest that are mobile or changing. Context-aware in contrast is used more generally to include nearby people, devices, lighting, noise level, network availability, and even the social situation; e.g., whether you are with your family or a friend from school.
- leave anything related to transport, communication to other layers- use this revised CEP to express and execute event-relevant logic, the purpose of which is to translate the ambient events into relevant business events- have these business events trigger business processes (however lightweight you want to make them)- have these business processes invoke decision services implemented through decision management to decide what they should be doing at every step- have the business processes invoke action services to execute the actions decided by the decision services- all the while generating business events or ambient events- etc.
A common task in many event processing systems is to detect patterns of events.
If combined, these patterns will eventually form a situation consisting of multiple patterns over time.
So basically a detected instance of a situation is a specific sequence of events.
G. Abowd, A. Dey, P. Brown, N. Davies, M. Smith, and P. Steggles. HUC '99: Proceedings of the 1st international symposium on Handheld and Ubiquitous Computing, page 304--307. London, UK, Springer-Verlag, (1999)
E. Mohyeldin, M. Fahrmair, W. Sitou, and B. Spanfelner. The 16th Annual IEEE International Symposium on Personal Indoor and Mobile Radio Communications (PIMRC05), 11-14 September 2005, Berlin, Germany, (2005)