Thesis (M.S.)--Rochester Institute of Technology, 1989. / "References": leaves 26-28.

Thesis (MSc (Hons.)) -- University of Western Sydney, Nepean, 2000. / "A thesis submitted for the degree of Master of Science (Honours)-Computing at University of Western Sydney - Nepean" Includes bibliographical references (leaves 117-121).

Thesis (M. Phil.)--Hong Kong University of Science and Technology, 2002. / Includes bibliographical references (leaves 49-51). Also available in electronic version. Access restricted to campus users.

Thesis (Ph.D.)--University of Alberta, 2010. / Title from PDF file main screen (viewed on Apr. 30, 2010). A thesis submitted to the Faculty of Graduate Studies and Research in partial fulfillment of the requirements for the degree of Doctor of Philosophy, Department of Computing Science, University of Alberta. Includes bibliographical references.

Thesis (M.S.)--Oregon Graduate Center, 1987.

Thesis (Ph. D.)--Oregon Graduate Center, 1987.

Logic programming realizes the ideal of "computation as deduction," except when floating-point arithmetic is involved. In that respect, logic programming languages suffer the same deficiency as conventional algorithmic languages: floating-point operations are only approximate and it is not easy to tell how good the approximation is. This dissertation proposes a framework to extend the benefits of logic programming to computations involving floating-point arithmetic. John Cleary incorporated a relational form of interval arithmetic into Prolog so that variables already bound can be bound again. In this way, the usual logical interpretation of computation no longer holds. Based on Cleary's idea, we develop a technique for narrowing intervals. We present a relaxation algorithm for coordinating the applications of the interval narrowing operations to constraints in a network. We incorporate relational interval arithmetic into two constraint logic programming languages: CHIP and CLP(R). We modify CHIP by allowing domains to be intervals of real numbers. In CLP(R) we represent intervals by inequality constraints. The enhanced languages ICHIP and ICLP(R) preserve the semantics of logic so that numerical computations are deductions, even when floating-point arithmetic is used. We have constructed a prototype of ICLP(R) consisting of a meta-interpreter executed by an existing CLP(R) system. We show that interval narrowing belongs to the class of domain restriction operations in constraint-satisfaction algorithms. To establish a general framework for these operations, we use and generalize Ashby's notions of cylindrical closure and cylindrance. We show that Mackworth's algorithms can be placed in our framework. / Graduate

The expressive power of logic-programming languages allows utilization of conventional constructs in development of computer systems based on logic programming. However, logic-programming languages have many novel features and capabilities. This thesis investigates how advantage can be taken of these features in the development of a logic-based computer system. It demonstrates that innovative approaches to software, hardware, and computer system design and implementation are feasible in a logic-programming context and often preferable to adaptation of conventional ones. The investigation centers on three main ideas: executable specification, declarative I/O, and implementation through transformation and meta-interpretation. A particular class of languages supporting parallel computation, committed-choice logic-programming languages, are emphasized. One member of this class, Concurrent Prolog, serves as the machine, specification, and implementation language. The investigation has several facets. Hardware, software, and overall system models for a logic-based computer are determined and examined. The models are described by logic programs. The computer system is represented as a goal for resolution. The clauses involved in the subsequent reduction steps constitute its specification. The same clauses also describe the manner in which the computer system is initiated. Frameworks are given for developing models of peripheral devices whose actions and interactions can be declaratively expressed. Interactions do not rely on side-effects or destructive assignment, and are term-based. A methodology is presented for realizing (prototypic) implementations from device specifications. The methodology is based on source-to-source transformation and meta-interpretation. A magnetic disk memory is used as a representative example, resulting in an innovative approach to secondary storage in a logic-programming environment. Building on these accomplishments, a file system for a logic-based computer system is developed. The file system follows a simple model and supports term-based, declarative I/O. Throughout the thesis, features of the logic-programming paradigm are demonstrated and exploited. Interesting and innovative concepts established include: device processes and device processors; restartable and perpetual devices and systems; peripheral devices modelled as function computations or independent logical (inference) systems; unique, compact representations of terms; lazy term expansion; files systems as perpetual processes maintaining local states; and term- and unification-based file abstractions. Logic programs are the sole formalism for specifications and implementations. / Science, Faculty of / Computer Science, Department of / Graduate

No description available.

The general area of developing, applying and studying new and parallel models of computation is motivated by a need to overcome the limits of current Von Neumann based architectures. A key area of research in understanding how new technology can be applied to Al problem solving is through using logic languages. Logic programming languages provide a procedural interpretation for sentences of first order logic, mainly using a class of sentence called Horn clauses. Horn clauses are open to a wide variety of parallel evaluation models, giving possible speed-ups and alternative parallel models of execution. The research in this thesis is concerned with investigating one class of parallel logic language known as Committed Choice Non-Deterministic languages. The investigation considers the inherent parallel behaviour of Al programs implemented in the CCND languages and the effect of various alternatives open to language implementors and designers. This is achieved by considering how various Al programming techniques map to alternative language designs and the behaviour of these Al programs on alternative implementations of these languages. The aim of this work is to investigate how Al programming techniques are affected (qualitatively and quantitatively) by particular language features. The qualitative evaluation is a consideration of how Al programs can be mapped to the various CCND languages. The applications considered are general search algorithms (which focuses on the committed choice nature of the languages); chart parsing (which focuses on the differences between safe and unsafe languages); and meta-level inference (which focuses on the difference between deep and flat languages). The quantitative evaluation considers the inherent parallel behaviour of the resulting programs and the effect of possible implementation alternatives on this inherent behaviour. To carry out this quantitative evaluation we have implemented a system which improves on the current interpreter based evaluation systems. The new system has an improved model of execution and allows several