1,479 research outputs found
Investigation, Development, and Evaluation of Performance Proving for Fault-tolerant Computers
A number of methodologies for verifying systems and computer based tools that assist users in verifying their systems were developed. These tools were applied to verify in part the SIFT ultrareliable aircraft computer. Topics covered included: STP theorem prover; design verification of SIFT; high level language code verification; assembly language level verification; numerical algorithm verification; verification of flight control programs; and verification of hardware logic
Type-driven natural language analysis
The purpose of this thesis is in showing how recent developments in logic programming can be exploited to encode in a computational environment the features of certain linguistic theories. We are in this way able to make available for the purpose of natural language processing sophisticated capabilities of linguistic analysis directly justified by well developed grammatical frameworks.
More specifically, we exploit hypothetical reasoning, recently proposed as one of the possible directions to widen logic programming, to account for the syntax of filler-gap dependencies along the lines of linguistic theories such as Generalized Phrase Structure Grammar and Categorial Grammar. Moreover, we make use, for the purpose of semantic analysis of the same kind of phenomena, of another recently proposed extension, interestingly related to the previous one, namely the idea of replacing first-order terms with the more expressive λ-terms of λ-Calculus
Graph Grammars for Knowledge Representation
This report consists of two papers presented at the March 1990 GRAGRA meeting in Bremen: the more general ''Representation of knowledge using graph grammars'' which argues for graphs as the universal KR formalism and the more specific ''The four musicians: analogies and expert systems -- a graphic approach'' which demonstrates the use of graphics for type inheritance and analogical reasoning
Proceedings of the Workshop on the lambda-Prolog Programming Language
The expressiveness of logic programs can be greatly increased over first-order Horn clauses through a stronger emphasis on logical connectives and by admitting various forms of higher-order quantification. The logic of hereditary Harrop formulas and the notion of uniform proof have been developed to provide a foundation for more expressive logic programming languages. The λ-Prolog language is actively being developed on top of these foundational considerations. The rich logical foundations of λ-Prolog provides it with declarative approaches to modular programming, hypothetical reasoning, higher-order programming, polymorphic typing, and meta-programming. These aspects of λ-Prolog have made it valuable as a higher-level language for the specification and implementation of programs in numerous areas, including natural language, automated reasoning, program transformation, and databases
Fuzzy expert systems in civil engineering
Imperial Users onl
A Friendly Introduction to Mathematical Logic
At the intersection of mathematics, computer science, and philosophy, mathematical logic examines the power and limitations of formal mathematical thinking. In this expansion of Leary’s user-friendly 1st edition, readers with no previous study in the field are introduced to the basics of model theory, proof theory, and computability theory. The text is designed to be used either in an upper division undergraduate classroom, or for self study. Updating the 1st Edition’s treatment of languages, structures, and deductions, leading to rigorous proofs of Gödel’s First and Second Incompleteness Theorems, the expanded 2nd Edition includes a new introduction to incompleteness through computability as well as solutions to selected exercises. Available on Lulu.com, IndiBound.com, and Amazon.com, as well as wholesale through Ingram Content Group.https://knightscholar.geneseo.edu/geneseo-authors/1005/thumbnail.jp
Mechanizing Structural Induction
This thesis proposes improved methods for the automatic
generation of proofs by structural induction in a formal system. The
main application considered is proving properties of programs. The
theorem-proving problem divides into two parts: (1) a formal
system, and (2) proof generating methods.
A formal system is presented which allows for a typed
language; thus, abstract data types can be naturally defined in it.
Its main feature is a general structural induction rule using a
lexicographic ordering based on the substructure ordering induced by
type definitions. The proof generating system is carefully introduced in order
to convince of its consistency. It is meant to bring solutions to
three problems. Firstly, it offers a method for generalizing only
certain occurrences of a term in a theorem; this is achieved by
associating generalization with the selection of induction
variables. Secondly, it treats another generalization problem:
that of terms occurring in the positions of arguments which vary
within function definitions, besides recursion controlling
arguments. The method is called indirect generalization, since it
uses specialization as a means of attaining generalization.
Thirdly, it presents a sound strategy for using the general induction rule which takes into account all induction subgoals, and
for each of them, all induction hypotheses. Only then are the
hypotheses retained and instantiated, or rejected altogether,
according to their potential usefulness. The system also includes a
search mechanism for counter-examples to conjectures, and a fast
simplification algorithm
Machine Assisted Proofs for Generic Semantics to Compiler Transformation Correctness Theorems
This thesis investigates the issues involved in the creation of a "general theory of operational semantics" in LEGO, a type-theoretic theorem proving environment implementing a constructionist logic. Such a general theory permits the ability to manipulate and reason about operational semantics both individually and as a class. The motivation for this lies in the studies of semantics directed compiler generation in which a set of generic semantics transforming functions can help convert arbitrary semantic definitions to abstract machines. Such transformations require correctness theorems that quantify over the class of operational semantics. In implementation terms this indicates the need to ensure both the class of operational semantics and the means of inferring results thereon remain at the theorem prover level. The endeavour of this thesis can be seen as assessing both the requirements that general theories of semantics impose on proof assistants and the efficacy of proof assistants in modelling such theories
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