Defining a Strategy to Select Either of Closed/Open World Assumptions on Semantic Robots

Abstract

Semantic Web technology is based on the OpenWorld Assumption (OWA) where absence of entities being searched does not entail negative response rather simply treated as facts "not available at the moment." On the one hand that indicates anticipation of future enhancements of the fact store while in other cases it is not preferred in situations where an authoritative answer is needed. Closed World Assumption (CWA) on the other hand returns definitive yes/no answers even in situations where future enhancements are inevitable. We wish to distinguish among the situations where one or the other assumption would be advantageous to use. Such distinction could cater for faster services discovery and more wholesome services orchestration. We apply this approach to discovering semantic Web services being offered by autonomous semantic robots out in the field and for building the unified worldview common to all. Consequently, the OWA-based paradigm alone is not suitable for most robotics platforms where cardinality and negation is not sound as well as in CWA. Therefore, we argue and display that a strategy to draw and utilize benefits of both world assumptions is beneficial.

On least coherence-preserving negations

“…This semantics is based in the well-known open world assumption semantics introduced in bi-valued logics [10], [11], [12], [13]. This non-compositional approach, when assigning truth-values to negated propositional symbols, implies the need to generalize the notion of inconsistent L-interpretation in this framework.…”

The Semantic Production of Space: Pervasive Computing and the Urban Landscape

“…By contrast, Baresi, Di Nitto, and Ghezzi explained that "traditional software development is based on the closed-world assumption that the boundary between system and environment is known and unchanging" (2006, page 36). Others have similarly suggested (Elci et al, 2008;Weishan et al, 2009) that in a closed world knowledge is presumed to be static, and that what is contained by databases represents a limit to what can be known by software applications. In a closed world, the possible is made explicit by the sum of existing knowledge-if it is known, then it is possible; if it is not known, then it is not possible.…”

Towards Semantically Intelligent Robots

“…While, that sets the base in anticipation of future enhancements of the fact base, it is not preferred in situations where a definitive answer is needed. Closed World Assumption (CWA) alternatively returns definitive yes/no answers even in situations where future enhancements are inevitable (Elçi et al, 2008). It is also essential to derive partial results from a set of cooperative agents/robots based on Locally Close World (LCW) settings (Doherty et al, 2000).…”

“…In cooperative robotics, such as Cooperative Labyrinth Discovery (CLD) (Elçi & Rahnama, 30 Nov -1 Dec 2006), (Elçi & Rahnama, 2009) in an uncharted labyrinth, conventionally, the probability and the estimation were used to select one path among a set of possible but as yet undiscovered ones. In order to overcome naïve decision making, according to (Elçi et al, 2008) a hybrid scheme is needed to serve as decision maker. Following algorithm is a revised and simplified version of the one presented at (Elci & Rahnama, 2009) to suite the limited capacity CCLDRs by dividing it into two phases running cooperative decision making on SCLDRs and local standalone decision making on CCLDRs.…”