<p>Fuzzing, a technique for negative testing of programs using randomly mutated or gen?erated input data, is responsible for the discovery of thousands of bugs in software from web browsers to video players. Advances in fuzzing focus on various methods for enhancing the number of bugs found and reducing the time spent to find them by applying various static, dynamic, and symbolic binary analysis techniques. As a stochastic process, fuzzing is an inherently inefficient method for discovering bugs residing in deep logic of programs due to the compounding complexity of preconditions as paths in programs grow in length. We propose a novel system to overcome this limitation by abstracting away path-constraining preconditions from a statement level to a function level by identifying impeding functions, functions that inhibit control flow from proceeding. REFACE is an end-to-end system for enhancing the capabilities of an existing fuzzer by generating variant binaries that present an easier-to-fuzz interface and expands an ongoing fuzzing campaign with minimal offline overhead. REFACE operates entirely on binary programs, requiring no source code or sym?bols to run, and is fuzzer-agnostic. This enhancement represents a step forward in a new direction toward abstraction of code that has historically presented a significant barrier to fuzzing and aims to make incremental progress by way of several ancillary dataflow analysis techniques with potential wide applicability. We attain a significant improvement in speed of obtaining maximum coverage, re-discover one known bug, and discover one possible new bug in a binary program during evaluation against an un-modified state-of-the-art fuzzer with no augmentation.</p>

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<p> This thesis presents a virtual material testing laboratory that is highly generic and flexible in terms of both the material behaviour and experiments that it supports. Generic and flexible material behaviour was accomplished via symbolic computation, generative programming techniques and an abstraction layer that effectively hides the material model specific portions of the numerical algorithms. To specify a given member of the family of material models a domain specific language (DSL) was created. A compiler, which uses the Maple computer algebra system, transforms the DSL into an abstract material class. Three different numerical algorithms, including a return map algorithm, are presented in the thesis to illustrate the advantage of the abstract material model. To accomplish the goal of generic and flexible experiments the finite element method was employed and an API that supports both load and displacement controlled experiments, as well as the capability for the experiments to modify their state over time, was developed. The virtual laboratory provides a family of material models with the following behaviours: elastic, viscous, shear-thinning, shear-thickening, strain hardening, viscoelastic, viscoplastic and plastic. As well, the developed framework, by using the Ruby programming language, provides support for a wide variety of programmable experiments, including: uniaxial, biaxial, multiaxial extension and compression, shear and triaxial. </p> / Thesis / Candidate in Philosophy

This thesis embodies the results of an investigation of a residence exclusively devoted to those who r blind. Working within the theoretical perspective of symbolic interactionism, the primary focus of this study was to discover whether relationship existed between the pattern of group organization within the residence and the perception of the attitudes of the sighted towards the blind. Underlying its approach was the assumption that how the residents perceived the attitudes of the sighted was related to how they evaluated themselves. A second focus of this study was to determine the basis and extent of group formation within the residence. / Thesis / Master of Arts (MA)