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COLAB: Knowledge Representation and Compilation Laboratory

This directory contains the COmpilation LABoratory (COLAB). COLAB is a hybrid knowledge representation system emphasizing the horizontal and vertical compilation of knowledge bases. It has been designed as a COmpilation LABoratory aiming at a synergetic collaboration of different knowledge representation and reasoning formalisms. It is comprised of subsystems dealing with different kinds of knowledge and that can also be used as stand-alone systems. The COLAB representation architecture splits into two main parts, an affirmative part, sometimes also called `assertional', and a taxonomic part. The affirmative part provides efficient reasoning with different kinds of relational or functional knowledge using tailored inference engines. For affirmative knowledge represented as constraint nets COLAB supplies constraint propagation techniques (CONTAX). Relational knowledge in the form of Horn rules is processed by forward (FORWARD) and backward (RELFUN) chaining. The backward component is also suited for expressing (non-deterministic) functional dependencies. Taxonomic knowledge is represented by intensional concept definitions which are automatically arranged in a subsumption hierarchy (TAXON). Dynamic cooperation of the subsystems is organized through access primitives providing an interface to the respective reasoning services. COLAB is a piece of research software developed at DFKI and the University of Kaiserslautern. COLAB involves 4 subsystems: + RELFUN is a logic-programming language with call-by-value (eager), non-deterministic, non-ground functions, and higher-order operations [Boley92b]. SHORT DESCRIPTION: Operational (interpreter in pure LISP), procedural (SLV-resolution), fixpoint, and model-theoretic semantics [Boley92c]. Interpreter for full RELFUN; WAM emulator for fixed-arity subset. Layered compiler system, from source-to-source transformers to declarative classifier, to WAM-code generator [Boley90a]. Translator to relational subset of RELFUN, henceforth to PROLOG. Accepting freely interchangeable LISP-style and PROLOG-style syntaxes. Tracer for valued conjunctions; interface to LISP; on-line help. Prelude with useful relations/functions; library of declarative hypergraph operations [Boley92a]; components for mechanical-engineering system using declarative geometry [BoleyHanschke+91b]. Tight (WAM-level) coupling with FORWARD. + TAXON is a terminological knowledge representation system extended by concrete domains [BaaderHanschke91b,Hanschke92b]. SHORT DESCRIPTION: Comprises a T-box and an A-box formalism for representing terminological and assertional knowledge. The T-box provides expressive concept forming operators, in particular for specifying role/attribute interaction. The TAXON A-box can instantiate concepts, roles, etc. All reasoning services (e.g., classification, realization) are implemented by terminating, sound and complete algorithms. A concrete domain of rational numbers with comparison operators is tightly coupled with the abstract terminological formalism. Can compute the domain hierarchy for CONTAX. + CONTAX is a constraint system for weighted constraints over hierarchically structured finite domains. SHORT DESCRIPTION: The CONTAX system supports primitive (extensional), compound (conjunctive), disjunctive and predicative constraints. Constraint instances are connected by variables that range over specific domains which can be plain or hierarchically structured. Hierarchical domains can be defined in CONTAX itself or by using the classifier of TAXON. Intervals regarded as subdomains of integers are also supported. All constraints are given a weight (from a discrete set ranging from 'hard' to 'soft') that is used by CONTAX for relaxation of overspecified problems. Besides being integrated in COLAB, there also exists a stand-alone version of CONTAX with a programmer interface to LISP [MeyerSteinle92] that enables any LISP-based application to use CONTAX as its own constraint-reasoning formalism. The CONTAX system has already been used to formalize the tool selection problem in a CIM application [Meyer92a,Meyer92b]. + FORWARD is a logic programming language with bottom-up and top-down evaluation of Horn clauses [HarmHinkelmann+92]. SHORT DESCRIPTION: User-specifiable division of Horn clauses for bottom-up, top-down and bidirectional reasoning. Semi-naive bottom-up evaluation with top-down provable premises. Generalized Magic-Set transformation for goal-directed bottom-up reasoning, supporting conjunctive queries and considering top-down premises. An interpreter version is available, there is also an abstract machine, which will be available in the near future. Simulation of forward chaining in a backward chaining system by rule transformation. Compilation into a WAM with special forward code area and additional so-called retain stack for derived facts. Upside-down meta-interpreter in RELFUN for forward chaining, partial evaluation of the meta-interpreter. Tight coupling with the RELFUN system on interpreter-level and WAM-level. A tight integration of the semi-naive strategy with the TAXON system is currently under development. Other subsystems used in COLAB include - GAMA (General Abstract Machine Assembler) - NyWAM (WAM emulator in Common Lisp)
Requires: Common Lisp (all), CLOS (CONTAX) Ports: RELFUN tested in AKCL, Lucid CL, Allegro CL, and Symbolics CL. TAXON in AKCL, Lucid CL, and Symbolics CL. CONTAX in Symbolic CL and Lucid CL. FORWARD in AKCL, Lucid CL, and Symbolics CL. Copying: Copyright (c) 1985-1992 by Harold Boley. (COLAB, RELFUN) Copyright (c) 1992 by Michael Sintek (GAMA) Copyright (c) 1991/1992 by Michael Sintek and Werner Stein (indexing concept and algorithms) Copyright (c) 1992 by Michael Herfert (lisp2pro/pro2lisp) This software is distributed for non-profit and research purposes only. Copyright (c) May 1989 by Sven-Olof Nystroem and Uppsala University. (NyWAM) Redistribution permitted but not for resale. Copyright (c) 1986 Regents of the University of California (Defsystem) Use, copying, modification, and distribution permitted. CD-ROM: Prime Time Freeware for AI, Issue 1-1 Author(s): Dr. Harold Boley (COLAB/RELFUN) DFKI Postfach 2080 W-6750 Kaiserslautern Germany Tel: +49-631-205-3459 Fax: +49-631-205-3210 Knut Hinkelmann (COLAB/FORWARD) DFKI Postfach 2080 67608 Kaiserslautern Germany Tel: +49-631-205-3467 Fax: +49-631-205-3210 Manfred Meyer (COLAB/CONTAX) DFKI Postfach 2080 67608 Kaiserslautern Germany Tel: +49-631-205-3468 Fax: +49-631-205-3210 Philipp Hanschke (COLAB/TAXON) DFKI Postfach 2080 67608 Kaiserslautern Germany Tel: +49-631-205-3460 Fax: +49-631-205-3210 Contact: Dr. Harold Boley (COLAB) DFKI Postfach 2080 W-6750 Kaiserslautern Germany Tel: +49-631-205-3459 Fax: +49-631-205-3210 Contact the principle developer of each subsystem for matters concerning that system. Requests for the entire system should be directed to Harold Boley. Keywords: Assertional Knowledge, Authors!Boley, Authors!Hanschke, Authors!Hinkelmann, Authors!Meyer, Backward Chaining, COLAB, CONTAX, Constraint Nets, Constraint Systems, FORWARD, Finite Domains, Forward Chaining, GAMA, GWAM, Horn Clauses, Intensional, Knowledge Compilation, Knowledge Representation, Lisp!Code, Logic Programming, NyWAM, RELFUN, Subsumption Hierarchy, TAXON, Taxonomic Knowledge, Terminological Knowledge Representation, WAM References: Franz Baader and Philipp Hanschke, "A Scheme for Integrating Concrete Domains into Concept Languages", in Proceedings of the 12th International Joint Conference on Artificial Intelligence, 1991. Franz Baader and Philipp Hanschke, "Extensions of Concept Languages for a Mechanical Engineering Application", in GWAI92, 1992. H. Boley, P. Hanschke, K. Hinkelmann, and M. Meyer, "COLAB: A Hybrid Knowledge Compilation Laboratory", Presented at 3rd International Workshop on Data, Expert Knowledge and Decisions: Using Knowledge to Transform Data into Information for Decision Support, Reisensburg, Germany, DFKI GmbH, September 1991. Harold Boley, "A Relational/Functional Language and Its Compilation into the WAM", Universit{\"a}t Kaiserslautern, Fachbereich Informatik, SEKI Report SR-90-05, April 1990. Harold Boley, "Declarative Operations on Nets", Research Report RR-90-12, DFKI GmbH, Postfach 20 80, D-6750 Kaiserslautern, October 1990. Harold Boley, "Declarative Operations on Nets", in Fritz Lehmann, editor, Semantic Networks in Artificial Intelligence, 23(6-9):601-637, Special Issue of Computers \& Mathematics with Applications, Pergamon Press, 1992. Harold Boley, "A Direct Semantic Characterization of RELFUN", in Evelina Lamma and Paola Mello, editors, Preprints of the Proceedings of the 3rd International Workshop on Extensions of Logic Programming, Facolt\`a di Ingegneria, Universit\`a di Bologna, Italy, 1992. Harold Boley, "Extended Logic-plus-Functional Programming", in Lars-Henrik Eriksson, Lars Halln{\"a}s, and Peter Schroeder-Heister, editors, Proceedings of the Workshop on Extensions of Logic Programming, ELP '91 (Stockholm 1991), Springer Verlag, 1992. Philipp Hanschke and Knut Hinkelmann, "Combining Terminological and Rule-based Reasoning for Abstraction Processes", in GWAI-92, Springer-Verlag, 1992. Philipp Hanschke and Manfred Meyer, "An Alternative to $\Theta$-Subsumption Based on Terminological Reasoning", in Celine Rouveirol, editor, Workshop on Logical Approaches to Machine Learning, ECAI 92, Vienna, August 1992. Philipp Hanschke, "Specifying Role Interaction in Concept Languages", in Third International Conference on Principles of Knowledge Representation and Reasoning (KR '92), October 1992. Philipp Hanschke, "Terminological Reasoning and Partial Inductive Definitions", in Lars-Henrik Eriksson, Lars Halln{\"a}s, and Peter Schroeder-Heister, editors, Workshop on Extensions to Logic Programming, (Stockholm 1991), Springer-Verlag, 1992. Martin Harm, Knut Hinkelmann, and Thomas Labisch, "Integrating Bottom-up and Top-down Reasoning in COLAB", DFKI GmbH, Tech Report Document D-92-27, 1992. H.-G. Hein and M. Meyer, "A WAM Compilation Scheme", in A. Voronkov, editor, Logic Programming: Proceedings of the $1^{st}$ and $2^{nd}$ Russian Conferences, Lecture Notes in Artificial Intelligence (LNAI) #592, pages 201-214, Springer-Verlag, Berlin, Heidelberg, 1992. Knut Hinkelmann, "Bidirectional Reasoning of Horn Clause Programs: Transformation and Compilation", DFKI GmbH, DFKI Technical Memo TM-91-02, January 1991. Knut Hinkelmann, "Forward Logic Evaluation: Compiling a Partially Evaluated Meta-interpreter into the WAM", in Proceedings German Workshop on Artificial Intelligence, GWAI-92, Springer-Verlag, September 1992. Manfred Meyer, "Using Hierarchical Constraint Satisfaction for Lathe-Tool Selection in a CIM Environment", in Fifth International Symposium on Artificial Intelligence (ISAI), Cancun, Mexico December 1992. Manfred Meyer, "Hierarchical Constraint Satisfaction and its Application in Computer-Aided Production Planning", in Expert Systems 92, Cambridge, U.K., December 1992. M. Meyer, H.-G. Hein, and J. M\"{u}ller}, "FIDO: Finite Domain Consistency Techniques in Logic Programming", in A. Voronkov, editor, Logic Programming: Proceedings of the $1^{st}$ and $2^{nd}$ Russian Conferences, Springer-Verlag, Berlin, Heidelberg, Lecture Notes in Artificial Intelligence (LNAI) #592, pages 294-301, 1992.
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