Browsing by Subject "Formal logic"

Now showing 1 - 9 of 9

Open Access
Correct-schema-guided synthesis of steadfast programs
(IEEE, 1997-11) Flener, Pierre; Lau, K. K.; Ornaghi, M.
It can be argued that for (semi-)automated software development, program schemas are indispensable, since they capture not only structured program design principles, but also domain knowledge, both of which are of crucial importance for hierarchical program synthesis. Most researchers represent schemas purely syntactically (as higher-order expressions). This means that the knowledge captured by a schema is not formalized. We take a semantic approach and show that a schema can be formalized as an open (first-order) logical theory that contains an open logic program. By using a special kind of correctness for open programs, called steadfastness, we can define and reason about the correctness of schemas. We also show how to use correct schemas to synthesize steadfast programs.
Open Access
Generalised logic program transformation schemas
(Springer, 1998-07) Büyükyıldız, Halime; Flener, Pierre
Schema-based logic program transformation has proven to be an eective technique for the optimisation of programs. This paper results from the research that began by investigating the suggestions in [11] to construct a more general database of transformation schemas for optimising logic programs at the declarative level. The proposed transformation schemas fully automate accumulator introduction (also known as descending computational generalisation), tupling generalisation (a special case of structural generalisation), and duality laws (which are extensions to relational programming of the rst duality law of the fold operators in functional programming). The schemas are proven correct. A prototype schema-based transformation system is evaluated. © Springer-Verlag Berlin Heidelberg 1998.
Open Access
Hypersolver: a graphical tool for commonsense set theory
(Elsevier, 1995) Pakkan, M.; Akman, V.
This paper investigates an alternative set theory (due to Aczel) called the Hyperset Theory. Aczel uses a graphical representation for sets and thereby allows the representation of non-well-founded sets. A program, called hypersolver, which can solve systems of equations defined in terms of sets in the universe of this new theory is presented. This may be a useful tool for commonsense reasoning. © 1995.
Open Access
Inductive logic program synthesis with dialogs
(Springer, 1996-08) Flener, Pierre
DIALOGS (Dialogue-based Inductive and Abductive LOGic program Synthesizer) is a schema-guided synthesizer of recursive logic programs; it takes the initiative and queries a (possibly computationally naive) specifier for evidence in her/his conceptual language. The specifier must know the answers to such simple queries, because otherwise s/he wouldn't even feel the need for the synthesized program. DIALOGS call be used by any learner (including itself) that detects, or merely conjectures, the necessity of invention of a new predicate. Due to its foundation on a powerful codification of a “recursion-theory” (by means of the template and constraints of a divide-and-conquer schema), DIALOGS needs very little evidence and is very fast. © Springer-Vertag Berlin Heidelberg 1997.
Open Access
Information-based approach to punctuation
(AAAI, 1997-07) Say, Bilge
This thesis analyzes, in an information-based framework, the semantic and discourse aspects of punctuation, drawing computational implications for Natural Language Processing (NLP) systems. The Discourse Representation Theory (DRT) is taken as the theoretical framework of the thesis. By following this analysis, it is hoped that NLP software writers will be able to make use of the punctuation marks effectively as well as reveal interesting linguistic phenomena in conjunction with punctuation marks.
Open Access
Issues in commonsense set theory
(Springer/Kluwer Academic Publishers, 1994) Pakkan, M.; Akman, V.
The success of set theory as a foundation for mathematics inspires its use in artificial intelligence, particularly in commonsense reasoning. In this survey, we briefly review classical set theory from an AI perspective, and then consider alternative set theories. Desirable properties of a possible commonsense set theory are investigated, treating different aspects like cumulative hierarchy, self-reference, cardinality, etc. Assorted examples from the ground-breaking research on the subject are also given. © 1995 Kluwer Academic Publishers.
Open Access
On correct program schemas
(Springer, Berlin, Heidelberg, 1998) Flener, Pierre; Lau, K. K.; Ornaghi, M.
We present our work on the representation and correctness of program schemas, in the context of logic program synthesis. Whereas most researchers represent schemas purely syntactically as higher-order expressions, we shall express a schema as an open rst-order theory that axiomatises a problem domain, called a specication framework, containing an open program that represents the template of the schema. We will show that using our approach we can dene a meaningful notion of correctness for schemas, viz. that correct program schemas can be expressed as parametric specication frameworks containing templates that are steadfast, i.e. programs that are always correct provided their open relations are computed correctly. © Springer-Verlag Berlin Heidelberg 1998.
Open Access
Using constrained intuitionistic linear logic for hybrid robotic planning problems
(IEEE, 2007) Saranlı, Uluç; Pfenning F.
Synthesis of robot behaviors towards nontrivial goals often requires reasoning about both discrete and continuous aspects of the underlying domain. Existing approaches in building automated tools for such synthesis problems attempt to augment methods from either discrete planning or continuous control with hybrid elements, but largely fail to ensure a uniform treatment of both aspects of the domain. In this paper, we present a new formalism, Constrained Intuitionistic Linear Logic (CILL), merging continuous constraint solvers with linear logic to yield a single language in which hybrid properties of robotic behaviors can be expressed and reasoned with. Following a gentle introduction to linear logic, we describe the two new connectives of CILL, introduced to interface the constraint domain with the logical fragment of the language. We then illustrate the application of CILL for robotic planning problems within the Balanced Blocks World, a "physically realistic" extension of the Blocks World domain. Even though some of the formal proofs for the semantic foundations of the language as well as an efficient implementation of a theorem prover are yet to be completed, CILL promises to be a powerful formalism in reasoning within hybrid domains. © 2007 IEEE.
Open Access
V. Lifschitz, ed., formalizing common sense: papers by John McCarthy
(Elsevier BV, 1995) Akman, V.
A review is presented of Lifschitz's collection of seventeen papers written by McCarthy on the subject of common sense. The book opens with a fine overview of McCarthy's research in artificial intelligence (AI). Lifschitz offers an admirably succinct account of the development of McCarthy's ideas on common sense from the early days of AI to his current work. Lifschitz's introduction is especially useful in appreciating the dramatically original and permanently influential nature of McCarthy's work. While McCarthy's papers collected in this volume were written over the span of almost three decades, Lifschitz correctly observes that the underlying concern has always been the same: to understand and model the intellectual ability realized by human common sense.