The crux of this investigation is the combination of realist and abstract elements in pictorial space and negotiating the various pictorial problems this sets in motion. The interaction between these elements, especially in a spatial sense, creates both a visual and conceptual ambiguity central to the meaning of the work. Multiple treatments of painted form -- realist, expressive and abstract are interleaved producing divergent visual sensations. The transition from one visual sensation to another, the way the eye traverses believable forms to suddenly collide with the canvas, forced there by raw, painted gesture, is an unpredictable journey invoking visual perplexity, thereby alerting the viewer to potential meanings; the research paintings are not just images of things, they are images of things that would not normally exist together, but do so to create a story. It is intended that the viewer be directed toward the subject of the painting as much as the qualities of the medium itself. Influences as diverse as art historical painting, photography, the motion and lighting effects of film, the qualities of surface reflections and chiaroscuro, have been sourced to facilitate a new body of work. Directing the relationship of the viewer to the paintings through format and scale, (generally life size or very small) promotes a similar kind of interaction (the need to get up close and far away) to that of the application of pictorial space. This is an important aspect of the research; the optical process of focussing in and out is a microcosm of looking at the paintings installed in physical space. The subject of the paintings is female sexuality and its connection to identity, relationships and self-expression. It is also the conceptual object of 'Multiplicity', a principal idea in the work, ambiguous pictorial situations suggesting reality is not one thing but a combination of remembered, existing and subconscious experience. In the research, this concept also pertains to the painter (using memory, experience and imagination) and the audience viewing the work at different times.

This project involves the examination of abstract, geometric paintings, kinetic sculptures, electronic art and installations that use opticality, perspectival space and colour relationships that destabilise compositional cohesion. Works made between 1964 and 1980, particularly those by Victor Vasarely and Bridget Riley are referenced in the determination of how geometric forms, colour transitions, interactions and juxtapositions have been used to suggest movement. This enquiry includes a review of the usage of planar space and the creation of optical effects. Artworks such as Bridget Riley's Chant 2, (1967) inform new works in which available digital technological processes are utilised. These new works consist mainly of compositions of line and coloured forms and are created in response to the outcomes of the research into the selected works. For example, static works that create movement through the use of colour and geometric form inform the creation of new w ork in media that uses motion. The artworks produced are installation-based works. The works include digital projections and static images that use painting processes as well as digital media. The objective of the project is to produce artworks that reference painting processes and extend explorations into colour usage designed to maximise optical effects and spatial disorientation. The artworks are intended to reflect elements researched whilst maximising the potential for using new media.

This paper shows that, provided circuits contain no zero-delay loops, a tight relationship, full abstraction, exists between a natural event-based operational semantics for circuits and a natural denotational semantics for circuits based on causal functions on value timelines. The paper also discusses what goes wrong if zero-delay loops are allowed, and illustrates the application of this semantic relationship to modeling questions.

We illustrate how the liberal use of high-order procedural abstractions and infinite streams helps us to express some of the vocabulary and methods of numerical analysis. We develop a software toolbox encapsulating the technique of Richardson extrapolation, and we apply these tools to the problems of numerical integration and differentiation. By separating the idea of Richardson extrapolation from its use in particular circumstances, we indicate how numerical programs can be written that exhibit the structure of the ideas from which they are formed.

Model checking is an automated technique for deciding whether a computer program satisfies a temporal property. Abstraction is the key to scaling model checking to industrial-sized problems, which approximates a large (or infinite) program by a smaller abstract model and lifts the model checking result over the abstract model back to the original program. In this thesis, we study abstraction in model checking based on \emph{exact-approximation}, which allows for verification and refutation of temporal properties within the same abstraction framework. Our work in this thesis is driven by problems from both practical and theoretical aspects of exact-approximation. We first address challenges of effectively applying symmetry reduction to \emph{virtually} symmetric programs. Symmetry reduction can be seen as a \emph{strong} exact-approximation technique, where a property holds on the original program if and only if it holds on the abstract model. In this thesis, we develop an efficient procedure for identifying virtual symmetry in programs. We also explore techniques for combining virtual symmetry with symbolic model checking. Our second study investigates model checking of \emph{recursive} programs. Previously, we have developed a software model checker for non-recursive programs based on exact-approximating predicate abstraction. In this thesis, we extend it to reachability and non-termination analysis of recursive programs. We propose a new program semantics that effectively removes call stacks while preserving reachability and non-termination. By doing this, we reduce recursive analysis to non-recursive one, which allows us to reuse existing abstract analysis in our software model checker to handle recursive programs. A variety of \emph{partial} transition systems have been proposed for construction of abstract models in exact-approximation. Our third study conducts a systematic analysis of them from both semantic and logical points of view. We analyze the connection between semantic and logical consistency of partial transition systems, compare the expressive power of different families of these formalisms, and discuss the precision of model checking over them. Abstraction based on exact-approximation uses a uniform framework to prove correctness and detect errors of computer programs. Our results in this thesis provide better understanding of this approach and extend its applicability in practice.

Model checking is an automated technique for deciding whether a computer program satisfies a temporal property. Abstraction is the key to scaling model checking to industrial-sized problems, which approximates a large (or infinite) program by a smaller abstract model and lifts the model checking result over the abstract model back to the original program. In this thesis, we study abstraction in model checking based on \emph{exact-approximation}, which allows for verification and refutation of temporal properties within the same abstraction framework. Our work in this thesis is driven by problems from both practical and theoretical aspects of exact-approximation. We first address challenges of effectively applying symmetry reduction to \emph{virtually} symmetric programs. Symmetry reduction can be seen as a \emph{strong} exact-approximation technique, where a property holds on the original program if and only if it holds on the abstract model. In this thesis, we develop an efficient procedure for identifying virtual symmetry in programs. We also explore techniques for combining virtual symmetry with symbolic model checking. Our second study investigates model checking of \emph{recursive} programs. Previously, we have developed a software model checker for non-recursive programs based on exact-approximating predicate abstraction. In this thesis, we extend it to reachability and non-termination analysis of recursive programs. We propose a new program semantics that effectively removes call stacks while preserving reachability and non-termination. By doing this, we reduce recursive analysis to non-recursive one, which allows us to reuse existing abstract analysis in our software model checker to handle recursive programs. A variety of \emph{partial} transition systems have been proposed for construction of abstract models in exact-approximation. Our third study conducts a systematic analysis of them from both semantic and logical points of view. We analyze the connection between semantic and logical consistency of partial transition systems, compare the expressive power of different families of these formalisms, and discuss the precision of model checking over them. Abstraction based on exact-approximation uses a uniform framework to prove correctness and detect errors of computer programs. Our results in this thesis provide better understanding of this approach and extend its applicability in practice.

This thesis presents a systematic and structured way to migrate embedded software running on a digital signal processor to a different hardware platform. The solution includes using design patterns, a layered architecture and clearly defined interfaces to perform hardware abstraction. The proposed solution is aimed for a particular embedded system used in a product at AI.

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Thèse doctorat : Informatique : Rennes 1 : 2008. / Titre provenant de la page du titre du document électronique. Bibliogr. p. 173-179.

Solvent-free peroxide-initiated polymer modifications are widely used to improve the physical and/or chemical properties of commodity plastics and elastomers. Although the reactions that underlie polymer grafting are known, our understanding of H-atom transfer reactions in this context is incomplete. Fundamental questions remain unanswered, such as the difference in reactivity between different polymers (polyethylene versus polypropylene and polyisobutylene) and differences in the regiochemical outcomes of grafting reactions upon them. Herein, experimental data pertaining to the H-atom transfers involved in polyolefin graft modifications were obtained to improve our fundamental understanding of these reactions by using radical-trapping techniques and quantum chemical calculations. In this project, experimental measurements of the efficiency of H-atom abstraction by t-butoxyl radicals from polyolefins, and suitable model compounds such as pentane, 2,4-dimethylpentane and 2,2,4,4-tetramethylpentane were determined. Insight is gained from alkyl-trapping experiments to quantify the relative reactivities of the primary, secondary and tertiary positions of the model compounds. Experimental data were compared to quantum chemical calculations, which revealed that entropic effects dictate the regioselectivity and preclude abstraction at the secondary position in favour of the less enthalpically-favourable primary abstraction site. MP2 and CBS-QB3 level calculations were able to reproduce experimental trends in model compound reactivity, while the highly common B3LYP density functional, used in other investigations on the subject, could not. / Thesis (Master, Chemical Engineering) -- Queen's University, 2011-10-20 16:48:38.083