A theory of contexts in information bases

Manos Theodorakis, Anastasia Analyti, Panos Constantopoulos, Nicolas Spyratos
2002 Information Systems  
| Although semantic data models provide expressive conceptual modeling mechanisms, they do not support context, i.e. providing controlled partial information on conceptual entities by viewing them from di erent viewpoints or in di erent situations. In this paper, we present a m o d e l f o r representing contexts in information bases along with a set of operations for manipulating c o n texts. These operations support context creation, update, copy, union, intersection, and di erence. In
more » ... lar, our operations of context union, intersection, and di erence are di erent from these of set theory as they take i n to account the notion of context. However, they also satisfy the important properties of commutativity, associativity, and distributivity. Our model contributes to the e cient handling of information, especially in distributed, cooperative e n vironments, as it enables (i) representing (possibly overlapping) partitions of an information base (ii) partial representations of objects, (iii) exible naming (e.g. relative names, synonyms and homonyms), (iv) focusing attention, and (v) combining and comparing di erent partial representations. This work advances towards the development o f a formal framework intended to clarify several theoretical and practical issues related to the notion of context. The use of context in a cooperative e n vironment is illustrated through a detailed example.
doi:10.1016/s0306-4379(01)00036-9 fatcat:qgufjgppuzfvtn5yws7rbhnx4q