Monthly Archive for September, 2010

Context-aware computing applications

B. Schilit, N. Adams, and R. Want, “Context-aware computing applications,” in WMCSA ’94: Proceedings of the 1994 First Workshop on Mobile Computing Systems and Applications, (Washington, DC, USA), pp. 85–90, IEEE Computer Society, 1994. [PDF]

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This paper describes software that reacts to an individual’s changing context. According to the authors, three important aspects of context are: where you are, who you are with, and what resources are nearby. Context includes different aspects of the physical environment around the user.

To investigate these topics they developed ParcTab, a small hand-held devices that uses infrared based cellular network for communication. The Tab acts as a graphics terminal and most of applications run on remote hosts.

Using this experimental environment, they describe four interaction mechanism:

  1. Proximate Selection, the located-objects that are nearby are emphasized or otherwise made easier to choose.
  2. Automatic Contextual Reconfiguration is the process of adding new components, removing existing components or altering the connections between components.
  3. Contextual Information and Commands happens when contextual information can produce different results accodring to the context in which they are issued.
  4. Context-Triggered Actions are sets of rules that specify how contex-aware systems should adapt.

ParcTAB.jpg

An operational definition of context

A. Zimmermann, A. Lorenz, and R. Oppermann, “An operational definition of context,” in CONTEXT’07: Proceedings of the 6th international and interdisciplinary conference on Modeling and using context, (Berlin, Heidelberg), pp. 558–571, Springer-Verlag, 2007. [PDF]

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This paper presents a summary of theoretical definitions of context that were developed in the past in the field of computer science. The authors’ argument presented in the paper is that most of the definitions that were proposed in the past were indirect definitions that used synonyms or that were either too general or incomplete.

By summarizing previous work, the authors presented an operational definition of context that could be used to characterize the situation of anentity. According to the authors, elements for the description of this context information fall into five categories:

  1. individuality
  2. activity
  3. location
  4. time
  5. relations

Also, according to the authors something is context because of the way it is used in interpretation, not due to its inherent properties. When interacting and communicating in everyday life, the perception of situations, as well as the interpretation of the context is a major part. Therefore, the author presents some operational additive to the general definition: context transitions, variation of approximation, change of focus, shift of attention, shared contexts, the establishment of relations, the adjustment of shared contexts, and the exploiting of relationships.

Zimmerman_context-petal-model.png

Toward a multidisciplinary model of context to support context-aware computing

N. A. Bradley and M. D. Dunlop, “Toward a multidisciplinary model of context to support context-aware computing,” Hum.-Comput. Interact., vol. 20, no. 4, pp. 403–446, 2005. [PDF]

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This paper presents a comprehensive literature review of multidisciplinary research on context. The primary aim of the authors was that of reviewing and merging theories of context within linguistic, computer science, and psychology to propose a multidisciplinary model of context that would facilitare application developers.

The authors find out that contextual interactions appered to comprise the cross-disciplinary component for understanding and using principles of context. From a liguistic perspective it is the interaction between two people, within computer science it is the user-application interaction (combined with possible interactions with other people and objects=, and within psychology it is the internal and external interactions. Last, contextual interactions should be considered also though the notion of embodiment, as described by Dourish (2001).