The aim of this essay is to explore in what way Graded Readers are different from authentic texts against the background of English as a Second Language (ESL) and the use of authentic and simplified text in ESL teaching. The material used for this purpose is the authentic text of Wuthering Heights by Emily Brontë and two upper-intermediate Graded Readers from two different publishers. The study uses the software readability-score and manual analysis to examine the texts with regards to lexical choice, language structure and story. The study showed that the Graded Readers are simplified in all aspects studied. Moreover, the Graded Readers differ from each other as well, most notably in the style of the text due to sentence structure and story simplification. This could imply that different authors of Graded Readers adopt different styles when simplifying text and that the grading levels are not comparable between different publishers. / <p>Engelska</p>

In this dissertation, we investigate whether consciousness is graded or dichotomous. Based on previous work and a level of processing framework, we hypothesize that consciousness in general, and visual experience specifically, can be conceived of as both graded and dichotomous. We present a series of experimental studies that provide support for this reasoning. We outline a set of future projects which can follow up on this research, and discuss the limitations of the current approach. / Doctorat en Sciences Psychologiques et de l'éducation / info:eu-repo/semantics/nonPublished

The Wavelet Finite Element Method (WFEM) involves combining the versatile wavelet analysis with the classical Finite Element Method (FEM) by utilizing the wavelet scaling functions as interpolating functions; providing an alternative to the conventional polynomial interpolation functions used in classical FEM. Wavelet analysis as a tool applied in WFEM has grown in popularity over the past decade and a half and the WFEM has demonstrated potential prowess to overcome some difficulties and limitations of FEM. This is particular for problems with regions of the solution domain where the gradient of the field variables are expected to vary fast or suddenly, leading to higher computational costs and/or inaccurate results. The properties of some of the various wavelet families such as compact support, multiresolution analysis (MRA), vanishing moments and the “two-scale” relations, make the use of wavelets in WFEM advantageous, particularly in the analysis of problems with strong nonlinearities, singularities and material property variations present. The wavelet based finite elements (WFEs) presented in this study, conceptually based on previous works, are constructed using the Daubechies and B-spline wavelet on the interval (BSWI) wavelet families. These two wavelet families possess the desired properties of multiresolution, compact support, the “two scale” relations and vanishing moments. The rod, beam and planar bar WFEs are used to study structural static and dynamic problems (moving load) via numerical examples. The dynamic analysis of functionally graded materials (FGMs) is further carried out through a new modified wavelet based finite element formulation using the Daubechies and BSWI wavelets, tailored for such classes of composite materials that have their properties varying spatially. Consequently, a modified algorithm of the multiscale Daubechies connection coefficients used in the formulation of the FGM elemental matrices and load vectors in wavelet space is presented and implemented in the formulation of the WFEs. The approach allows for the computation of the integral of the products of the Daubechies functions, and/or their derivatives, for different Daubechies function orders. The effects of varying the material distribution of a functionally graded (FG) beam on the natural frequency and dynamic response when subjected to a moving load for different velocity profiles are analysed. The dynamic responses of a FG beam resting on a viscoelastic foundation are also analysed for different material distributions, velocity and viscous damping profiles. The approximate solutions of the WFEM converge to the exact solution when the order and/or multiresolution scale of the WFE are increased. The results demonstrate that the Daubechies and B-spline based WFE solutions are highly accurate and require less number of elements than FEM due to the multiresolution property of WFEM. Furthermore, the applied moving load velocities and viscous damping influence the effects of varying the material distribution of FG beams on the dynamic response. Additional aspects of WFEM such as, the effect of altering the layout of the WFE and selection of the order of wavelet families to analyse static problems, are also presented in this study.

Marketing communications is regarded as a common function of all Web sites, even if this is not the express objective of the site. As no previous research specifically considered these issues, this study examined the extent to which lodges graded by the Tourism Grading Council of South Africa effectively use their Web sites as online marketing communications tools. A content analysis was used to investigate the Web sites of graded lodges according to a list of evaluation criteria based on the elements of the marketing communications mix (i.e., advertising, sales promotion, public relations, direct marketing and personal selling). A number of specific online marketing communications techniques that could be employed in a tourism firm’s Web site were identified from an extensive literature review for each element of the marketing communications mix. The extent to which these specific techniques were employed in the Web sites of the graded lodges was then determined. The findings show that the graded lodges are not using their Web sites effectively as online marketing communications tools for communications with their target audiences. Comparisons were also made between the three, four and five star lodges to determine whether differences were present in their Web sites based on their star grading. Overall, the lodges did not differ much in terms of the online marketing communications techniques that they employed and only slight differences existed. The main recommendation for this study is that the managers of South African graded lodges include as many of the 30 online marketing communications techniques investigated as possible in their Web sites. This study was limited as it only focused on lodges that have been graded by the Tourism Grading Council of South Africa and the findings cannot be generalised to all South African lodges or to other types of accommodation establishments. Potential reasons for the inclusion/exclusion of these techniques, whether the lodges maintain their Web sites themselves, what specific techniques Web site visitors regard as important and the fact that the researcher was the only coder of the sites were also limitations of this study that could be overcome in future research. Copyright / Dissertation (MCom)--University of Pretoria, 2007. / Marketing Management / MCom / Unrestricted

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In the last decade aluminium started to be considered as an alternative to steel to produce car body panels, especially considering the strict demands to decrease fuel consumption which require vehicle weight reduction. In order to keep their leading role, steel companies have to produce stronger materials to reduce the thickness of steel sheets used in cars and are now considering non-conventional steel making processes. The purpose of this PhD research was to investigate the possibility of strengthening thin sheets of interstitial free steel (IF steel) by using carbon rich films deposited on the steel surface using Physical Vapour Deposition (PVD). These films then act as a carbon reservoir which upon heat treatment release carbon in the IF steel and strengthen it. Coated tensile coupons 200 μm thick were annealed at different temperatures under high vacuum. Tensile tests show that a 100 MPa increase in yield stress can be obtained after annealing at 430 ˚C for 1h in high vacuum. The effects of annealing environment, film thickness and prestrain on carbon diffusion were also investigated. It was shown that carbon diffusion from the film to the IF steel substrate is limited by the film transformation into cementite at temperatures equal or higher than 530 ˚C. All tensile curves showed a plastic instability known as Lüders plateau, which is undesirable as it results in surface markings on the deformed part. FEM analyses were performed to find ways to suppress the Lüders plateau, proving that increasing strain-hardening or having a graded instead of uniform carbon content through thickness can suppress or limit Lüdering. The possibility of creating a through thickness gradient of microstructure was investigated as it could suppress Lüdering and result in higher strength. For these tests, FeC coated coupons were induction heated to 820 ˚C followed by water quenching. After only 2 minutes of heat treatment the yield stress was increased by 250 MPa and the ultimate tensile strength reached 400 MPa. With an annealing of 4 minutes, the Lüders plateau was fully suppressed and the microstructure consisted in ferrite grains and TiC nanocarbides. This work demonstrates that FeC films can be effectively used to diffuse carbon into steel and that a significant increase in mechanical properties can be obtained after a heat treatment of only a few minutes.

High Speed Machining (HSM) is associated with higher cutting velocities and table feedrates and higher material removal rate, lower cutting forces in contrast to conventional machining. HSM can be undertaken dry or near dry and hence it is considered as environmentally friendly machining in relation to the use of cutting fluids. A key challenge in HSM is that, the thermal loads generated during the cutting process can be a major driver of thermally activated wear mechanism and hence affect machining performance. The ability of cutting tools to act as thermal barrier can be a highly desirable property for dry and HSM. Recently, research work has been conducted on laboratory based coated cutting tools to model and understand the fraction of heat that enters the cutting tool. These studies have shown the potential for TiN and TiAlN coated tools in reducing heat partition to the cutting tool when compared to uncoated tools. This PhD extended this work to modelling and characterising the heat partition for new generation commercial coated cutting tools considering tools from major insert manufactures. For this study commercial coated carbide tools were classified into two groups. In one group were coatings uniformly applied on both rake and flank faces of the insert (SERIES). The second group were tools that had different top coats for the rake and flank faces (Functionally Graded). This concept of functional grading is used to tailor the coating selection to the conditions that exist on a tool face. Moreover, the issue of restricted chip contact was modelled and clarified in terms of its impact on heat partition. This chip breaker design is of particular importance to inserts used for machining ductile materials. Thus the PhD has applied research methods to industrial cutting tools and helped elucidate the important aspects relating to the design, layout and selection of multilayer coatings. The heat partition was quantified by using a combined Finite Element (FE) and experimental approach. This methodology was applied by taking into consideration the appropriate friction phenomena during HSM i.e. sticking and sliding. A restricted contact length with groove profile geometry was considered for the application of heat load in the FE model. Orthogonal and external turning of AISI/SAE 4140 medium carbon alloy steel was conducted over a wide range of cutting speeds. An infrared thermal imaging camera was used to measure cutting temperatures. The results show that the layout of the coating can significantly affect the heat distribution into the cutting tool, specifically; the top coat can alter the friction conditions between the tool-chip contact. The distribution of heat (heat partition) into the cutting tool insert with the thickest layer of Al2O3 as a top coating is the lowest in the entire range of cutting speeds tested i.e. 10.5% at lower cutting speed and reduced to 3.4% at highest cutting speed. Investigations were also conducted to quantify the contribution of heat from the primary and secondary deformation zones using a combination of finite element modelling, analytical modelling and experimental data. The results deduced that the primary deformation zone heat source contributes 9.1% (on average) to the heat partition into the cutting tool. The contribution of the Thesis should be of interest to those who design, manufacture and coat cutting tools. It defines heat partition values for commercial coated carbide tools, assesses the requirements for multilayer design of thermally insulating cutting tools, the selection of coating top layer coats and the role of contact phenomenon on heat partition in dry and HSM of steels.

The challenges in the deposition of dissimilar materials are mainly related to the large differences in the physical and chemical properties of the deposited and substrate materials. These differences readily cause residual stresses and intermetallic phases. This has led to the development of functionally graded materials which exhibit spatial variation in composition. Laser direct metal deposition due to its flexibility, it offers wide variety of dissimilar and functionally graded materials deposition. Despite considerable advances in process optimization, there is a rather limited understanding of the role of metallurgical factors in the laser deposition of dissimilar and functionally graded alloys. The aim of this work is to understand and explain mechanisms occurring in diode laser deposition of dissimilar materials and functionally graded materials. The first part of this work addressed diode laser deposition of Inconel 718 nickel alloy to Ti-6Al-4V titanium alloy. Here, the effect of laser pulse parameters and powder mass flow rates on the stress formation and cracking has evaluated by experiment and numerical techniques. Results showed that the clad thickness was an important factor affecting the cracking behaviour. In the second part of this study, an image analysis technique has been developed to measure the surface disturbance and the melt pool cross section size during laser direct metal deposition of Inconel 718 on a Ti-6Al-4V thin wall. It was noted that under tested conditions the overall melt pool area increased with the increase in powder flow rate; the powder carrier gas flow rates also seemed to play important roles in determining the melt pool size. In the third part of this study, a parametric study on the development of Inconel 718 and Stainless steel 316L continuously graded structure has been carried out. Results suggested that microstructure and other mechanical properties can be selectively controlled across the deposited wall. The results presented in this dissertation can be used as a metallurgical basis for further development of dissimilar and functionally graded manufacturing using LDMD technique, guiding future manufacturing engineers to produce structurally sound and microstructurally desirable laser deposited samples.

The present study examined the structural construct validity of the LoTi Digital-Age Survey, a measure of teacher instructional practices with technology in the classroom. Teacher responses (N = 2840) from across the United States were used to assess factor structure of the instrument using both exploratory and confirmatory analyses. Parallel analysis suggests retaining a five-factor solution compared to the MAP test that suggests retaining a three-factor solution. Both analyses (EFA and CFA) indicate that changes need to be made to the current factor structure of the survey. The last two factors were composed of items that did not cover or accurately measure the content of the latent trait. Problematic items, such as items with crossloadings, were discussed. Suggestions were provided to improve the factor structure, items, and scale of the survey.

Orientador: Lucio Centrone / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Matemática Estatística e Computação Científica / Made available in DSpace on 2018-08-27T16:21:21Z (GMT). No. of bitstreams: 1 Lobo_MiqueiasdeMelo_M.pdf: 612489 bytes, checksum: 4f5b408cbd8a473c143ee07e289ce4fb (MD5) Previous issue date: 2015 / Resumo: Neste trabalho estudamos álgebras com identidades polinomiais. Mais especificamente, estudamos os principais teoremas de estrutura das PI-álgebras graduadas e entre eles a versão graduada do teorema de Posner, obtida por Balaba em 2005, que abriu o caminho para diversas aplicações importantes nos últimos anos / Abstract: In this work we study algebras with polynomial identities. More specifically, we study the main structure theorems for graded PI-algebras and including the graded version of Posner's theorem, obtained by Balaba in 2005, which paved the way for several important applications in recent years / Mestrado / Matematica / Mestre em Matemática