Building new knowledge-based systems today usually entails constructing new knowledge bases from scratch. It could instead be done by assembling reusable components. System developers would then only need to worry about creating the specialized knowledge and reasoners new to the specific task of their system. This new system would interoperate with existing systems, using them to perform some of its reasoning. In this way, declarative knowledge, problem- solving techniques, and reasoning services could all be shared among systems. This approach would facilitate building bigger and better systems cheaply. The infrastructure to support such sharing and reuse would lead to greater ubiquity of these systems, potentially transforming the knowledge industry. This article presents a vision of the future in which knowledge-based system development and operation is facilitated by infrastructure and technology for knowledge sharing. It describes an initiative currently under way to develop these ideas and suggests steps that must be taken in the future to try to realize this vision.
All the specialists are agreed that the possibility of adding to multimedia objects some sort of "conceptual" annotation describing their information content under a form suitable for computer processing would contribute greatly to solve the problem of their "intelligent" indexing and retrieval. The existing projects in this domain, like Information Manifold, UNTANGLE or MIHMA, propose to build up the conceptual annotation (or "generalised bookmark") making use of very complex conceptualanguages, like some sort of description logics. The major drawback of this approach concerns the difficulty of associating "by hand" a (syntactically very complex) generalised bookmark in the description logics style to WWW objects pertaining to a multimedia universe sufficiently large. To alleviate this problem, we propose -- in the context of a newly started project which concerns the establishment of detailed blueprints (and of a prototype) of a full object-oriented, WWW Distance Learning Environment -- to associate with the WWW objects not the final conceptual annotation, but a simple natural language (NL) caption in the form of short texts representing a general, neutral description of the informational content of the object. To accelerate this sort of operation, it could also be possible to make use of dictation systems like Dragon Dictate or IBM VoiceType.
Recent results have shown the interest of trees-of-BDDs as a suitable target language for propositional knowledge compilation from the practical side. In the present paper, the concept of tree-of-BDDs is extended to additional classes of data structures C, thus leading to trees-of-C representations (ToC). We provide a number of generic results enabling one to determine the queries/transformations satisfied by ToC depending on those satisfied by C. We also present some results about the spatial efficiency of the ToC languages. Focusing on the ToB language (and other related languages), we address a number of issues that remained open in (Subbarayan et al 2007). We show that beyond co and va, the ToB fragment satisfies im and me but satisfies neither cd nor any query among ce, se unlesssf P = NP. Among other results, we prove that ToB is not comparable w.r.t. succinctness with any of cnf, dnf, Dnnf unless the polynomial hierarchy collapses.This contributes to the explanation of some empirical results reported in (Subbarayan et al 2007).