Thesis (M.S.)--West Virginia University, 2005. / Title from document title page. Document formatted into pages; contains iv, 34 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 31-34).

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.

Universiẗat, Diss., 2000--Dortmund.

University, Diss., 2001--Saarbrücken.

University, Diss., 1994--Saarbrücken.

Techn. Universiẗat, Diss., 2004--Berlin.

Techn. Hochsch., Diss., 2005--Aachen.

Assessments of structures with postulated or existing defects are generally carried out using standards and engineering assessment procedures. Assessments of this type involve comparing an applied force, in this case the crack driving force, with a material property, which in this case is the material's resistance to fracture, its fracture toughness. The crack driving force J can be calculated directly or implicitly by using a failure assessment diagram. Assessments can be based on either the initiation of the growth of a crack or, when dealing with ductile fracture, on an amount, e.g. 2 mm, of ductile tearing. Material fracture toughness values are obtained by testing high constraint specimens such as deeply cracked compact tension specimens and single edge notched bend specimens under uniaxial loading conditions. The high constraint of the test specimens provides conservative measurements of the fracture toughness for most applications. However, this assumption of conservatism is not necessarily applicable where there are biaxial loading conditions. The literature concerning assessments of such components mainly discusses whether uniaxial loading conditions provide conservative estimates of fracture toughness. Crack driving forces under biaxial loading can be overestimated, leading to a loss of conservatism. Conversely, biaxial loading could be beneficial and thus an approach that is consistently conservative has implications for the cost and time involved in the consequences of prematurely assessing or predicting the failure of a structure or component. This research considers the effects of biaxial loading on all the parameters involved in the integrity assessment of structures, components and specimens with defects. These parameters include the crack driving force, material fracture toughness, internal stresses and limit loads. It will address their relative effects on the determination of failure when compared with the assumption of uniaxial loading. The methods used will be analytical, using the equations and theories of standard solid mechanics, fracture mechanics and existing advice in R6 and the literature, and numerical using finite element analyses. Experimental, analytical and numerical work in the literature will be assessed and discussed and their outcomes compared with the findings of this research. The overall aim is to provide more explicit advice on the assessment of defects in components under biaxial loading in the R6 procedure.

This thesis explores the spatiotemporal network dynamics underlying natural speech comprehension, as measured by electro-magnetoencephalography (E/MEG). I focus on the transient effects of incrementality and constraints in speech on access to lexical semantics. Through three E/MEG experiments I address two core issues in systems neuroscience of language: 1) What are the network dynamics underpinning cognitive computations that take place when we map sounds to rich semantic representations? 2) How do the prior semantic and syntactic contextual constraints facilitate this mapping? Experiment 1 investigated the cognitive processes and relevant networks that come online prior to a word’s recognition point (e.g. “f” for butterfly) as we access meaning through speech in isolation. The results revealed that 300 ms before the word is recognised, the speech incrementally activated matching phonological and semantic representations resulting in transient competition. This competition recruited LIFG, and modality specific regions (LSMG, LSTG for the phonological; LAG and MTG for the semantic domain). Immediately after the word’s recognition point the semantic representation of the target concept was boosted, and rapidly accessed recruiting bilateral MTG and AG. Experiment 2 explored the cortical networks underpinning contextual semantic processing in speech. Participant listened to two-word spoken phrases where the semantic constraint provided by the modifier was manipulated. To separate out cognitive networks that are modulated by semantic constraint from task positive networks I performed a temporal independent component analysis. Among 14 networks extracted, only the activity of bilateral AG was modulated by semantic constraint between -400 to -300 ms before the noun’s recognition point. Experiment 3 addressed the influence of sentential syntactic constraint on anticipation and activation of upcoming syntactic frames in speech. Participants listened to sentences with local syntactic ambiguities. The analysis of the connectivity dynamics in the left frontotemporal syntax network showed that the processing of sentences that contained the less anticipated syntactic structure showed early increased feedforward information flow in 0-100 ms, followed by increased recurrent connectivity between LIFG and LpMTG from the 200-500 ms from the verb onset. Altogether the three experiments reveal novel insights into transient cognitive networks recruited incrementally over time both in the absence of and with context, as the speech unfolds, and how the activation of these networks are modulated by contextual syntactic and semantic constraints. Further I provide neural evidence that contextual constraints serve to facilitate speech comprehension, and how the speech networks recover from failed anticipations.

The world’s population is ageing. Due to societal improvements in healthcare, living standards, and socio-economic status, more and more people are living to old age. The proportion of the world's population aged 65 or over is expected to increase from 11% in 1998 to 16% in 2025. This causes a major public health issue, because with increased age there is an increased risk of developing a number of age-related diseases. However, there is increasing scientific evidence that many of the biological changes and risks for chronic disease, which have traditionally been attributed to ageing, are in fact caused by malnutrition (sub-optimal diets and nutrient intakes). This report presents a constraint satisfaction approach to planning meals while taking into account amongst other things nutritional and economic factors. Two models for generating meal plans are presented and their respective strengths and weaknesses discussed. System design, implementation and the main algorithms used are described in more detail. These algorithms include Depth First Branch and Bound and its various improvements for meal plan generation as well as Item-based Collaborative Filtering for user preferences. Our test runs show that the system works well for smaller applications but runs into problems when the number of available recipes grows or a larger number of meals are planned. The tests also show that the two modelling approaches both have useful applications. Based on the test results some suggestions for further improvement of the system conclude the report.