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A research project at Linnaeus University focuses on optimizing theadhesives joints between wood and glass, with the aim of obtain stiffcomponents that can act as a load and stabilizing elements and still betransparent. But there is, however, still a lack of knowledge regarding theadhesive materials which need to be further investigated. This thesis focused on testing six different adhesives in relaxation and todetermine the viscosity (η) and modulus of elastic (MOE, E). Viscosity andMOE are then used in combination in a standard linear solid model (SLS)describing the viscoelasticity mathematically. Figures and tables are used topresent the results and the evaluation. The so determined parameters can beused in e.g. finite element models for the design of load bearing timber glasscomposites.

A Dissertation submitted in partial compliance with the requirements for the Master's Degree in Technology: Chiropractic, Durban Institute of Technology, 2003. / Headaches are one of the most common clinical problems in medicine (Edwards et al. 1995). It is estimated that one in three people suffer from headaches at some stage in their life (Kim et al. 1995). It is an extremely common complaint in the industrialized world (Nilsson, 1997) and has a significant impact on employee absenteeism, productivity and quality of life (Schwartz et al. 1997). In the United States more than 15 000 tons of Aspirin is consumed annually for the relief of headaches, and the cost of evaluation and treatment of headache patients consumes millions of dollars a year (Bernat and Vincent, 1993). Tension - type headache is the commonest form of headaches (Edwards et al. 1995). It is a highly prevalent condition experienced annually by 30 - 70% of the population, and as a chief complaint, it constitutes 5 - 8% of Chiropractic patients (Vernon and McDermaid, 1998). It is divided into an Episodic and Chronic form (IHS, 1991:29), with Episodic Tension-type headache being far more prevalent than Chronic Tension-type headache (Schwartz et al. 1998). Episodic Tension-type headache is further subdivided according to the presence or absence of a muscular factor. According to the International Headache Society (1991:29) for decades a dispute has prevailed concerning the importance of muscle contraction in the pathogenesis of the headache, but conclusive studies are still lacking (IHS, 1991:29). Based on the IHS (1991:29) classification that tension-type headache is associated with a muscular component, the purpose of this study was to investigate the effect of specific myofascial trigger point therapy in the clinical presentation of Episodic Tension-type headache. / M

This degree work is about the exploration of the stretch in textile materials by using cartridge pleats as a method to create weight and thereby create tension. Through research in materials and stretch fabrics versus heavier woven textiles the work strives for expressions in movement as well as new ways of combining lightness and weight. / Program: Modedesignutbildningen

Les îles sont à priori des lieux propices au développement de l’énergie éolienne. En premier lieu les coûts de production des moyens conventionnels sont plus élevés que sur les réseaux interconnectés. En deuxième lieu, il subsiste un potentiel éolien important à exploiter dans ces régions. Enfin, les éoliennes permettent de réduire la dépendance énergétique vis-à-vis de produits fossiles, de respecter les engagements en regard du protocole de Kyoto et d’assurer l’approvisionnement électrique futur de ces zones en pleine croissance.Il est donc logique que l’énergie éolienne soit actuellement en pleine croissance dans les réseaux insulaires. Ce phénomène inquiète les gestionnaires de ces réseaux car cette production est très différente de celles des sources conventionnelles. En plus, ces réseaux pourraient atteindre des niveaux de pénétration éolienne important très rapidement, compte tenu de leur faible taille. Or les réseaux insulaires sont plus fragiles que les réseaux interconnectés et l’insertion massive d’éoliennes s’accompagne de caractéristiques particulières pouvant dégrader le fonctionnement du système électrique.L’étude présentée dans ce mémoire a été réalisée afin d’analyser l’impact de l’augmentation de la production éolienne dans les réseaux insulaires et de proposer des solutions permettant le développement de ce moyen de production dans ces régions. Pour cela, plusieurs stratégies de contrôle ont été présentées. D’une part, deux stratégies de commande de la puissance réactive échangée entre les parcs éoliens et le réseau ont été comparées, afin de minimiser l’augmentation du niveau de tension dans les réseaux de distribution avec forte pénétration éolienne. D’autre part, deux stratégies de commande ont été implémentées en vue de faire participer la production éolienne au réglage de fréquence.Les stratégies de commande ont été implémentées sur Matlab-Simulink puis validées sur EUROSTAG. Elles ont été évaluées d’abord dans un réseau simplifié afin d’étudier plus précisément et de manière systématique l’influence du choix et du paramétrage de la commande sur le comportement dynamique d’un réseau faible. Puis, elles ont été étendues au cas de figure du réseau de distribution du Mont-Dore en Nouvelle Calédonie et du réseau de Guadeloupe / Islands are favourable places to the development of wind energy. Firstly, the production costs of the conventional generation are higher than on the interconnected grids. Secondly, there is an important wind potential in these regions. Finally, the wind energy makes possible to reduce the energy dependence of fossil products, to respect the Kyoto protocol and to ensure the future electricity supply of these regions with sustained growth.Currently, wind energy is fast-growing in the islands grids. This growth worries the grid operators because this production is very different from the conventional sources. Moreover, these grids could reach very quickly a high levels wind penetration because their low size. However, the insular grids are weak grids compare to the inter-connected grids. In this kind of grids, the massive insertion of wind turbines is accompanied by particular characteristics which might damage operation of the electric system. The present study was carried out in order to analyze the impact on increase wind energy penetration in the insular grids and to propose solutions allowing the development of this energy sources in these areas. In this respect, several strategies of control were proposed. Firstly, two control strategies of the reactive power exchanged by the wind farms with the grids were compared, in order to minimize the voltage increasing in the distribution grids with strong wind penetration. Secondly, two control strategies were implemented in order to regulate the grid frequency through wind turbines. The control strategies were implemented on Matlab-Simulink then validated on EUROSTAG. Initially, they were evaluated in a simplified network in order to study more precisely and in a systematic way the influence of the choice and parameter settings of control in the dynamic behaviour of a weak grid. Then, they were extended to the distribution grid of Mont-Dore in New Caledonia and to the Guadeloupe electric grid

Made available in DSpace on 2015-04-22T22:16:15Z (GMT). No. of bitstreams: 1 Almir Cunha da Gracas Neto.pdf: 379350 bytes, checksum: abf31b2ffa1155ab61fbf98c40bb9c57 (MD5) Previous issue date: 2007-09-18 / FAPEAM - Fundação de Amparo à Pesquisa do Estado do Amazonas / This dissertation is concerned with a detailed proof of a Ruh-Vilms theorem which characterize the isometric immersion of a Riemannian manifold into the Euclidean space whose the mean curvature vector is parallel as being that immersion whose the associated Gauss map is harmonic. / Este trabalho apresenta uma demonstração detalhada do teorema que caracteriza as imersões isométricas (fórmula matemática) de uma variedade Riemanniana n-dimensional no espaço Euclidiano (p + n)-dimensional com vetor curvatura média paralelo como sendo aquelas cuja aplicação de Gauss associada é harmônica. O resultado deve-se a E.A.Ruh e J. Vilms.

Este trabalho estuda o processo de trefilação combinada do aço SAE 1045, que consiste nas etapas de pré-endireitamento com múltiplos rolos, jateamento, trefilação, corte e endireitamento por rolos, tendo como produto final barras acabadas trefiladas. Este produto final é empregado na fabricação de hastes de amortecedores para indústria automotiva. O Objetivo do estudo é de entender como são geradas e como se comportam as principais heterogeneidades mecânicas do material processado e a influência dos parâmetros do processo e das características do material na formação e modificação dessas heterogeneidades, buscando como resultado parâmetros otimizados para o processo. Foram variados no processo três parâmetros e avaliadas a interação existente entre eles. Os parâmetros modificados foram ângulo da ferramenta de trefilação (fieira), o ângulo de endireitamento e polimento por rolos cruzados (PERC) e a colocação de revestimento de carbo-nitreto de titânio (TiCN) no núcleo da ferramenta de trefilação (fieira). Foi realizada caracterização do aço, como microestrutura, composição química e microdureza. As tensões residuais superficiais das amostras foram caracterizadas utilizando o método de difração de raios-X. Após avaliação das tensões residuais superficiais, foi analisada a variação das tensões com a profundidade através do método do furo cego (hole-drilling), A classificação das inclusões foi de acordo com o método microscópico A (“piores campos”) da norma ASTM E45-97, feita através da maior severidade encontrada analisando o material aleatoriamente através de varredura com microscópio em sua superfície. Os resultados obtidos permitiram conhecer a combinação de ângulo de fieira e de endireitamento por rolos cruzados (PERC) mais favoráveis para gerar níveis baixos de tensões residuais. Além do ângulo, foi possível verificar que a geometria das zonas da ferramenta de trefilação (fieira) influência os níveis de tensões residuais após a trefilação. O núcleo da fieira com revestimento em todos os ensaios realizados apresentou menores níveis de tensões residuais, mostrando ser uma condição importante para a otimização do processo principalmente para a redução das tensões trativas após a trefilação. / This paper studies the process of cold drawing combined SAE 1045 steel, which consists of the steps with multiple pre-straightening rolls, sandblasting, drawing, cutting and straightening by rollers, with the final product finished extruded bars. This final product is used in the manufacture of rods of shock absorbers for the automotive industry. The objective of the study is to understand how they are generated and how they behave the main mechanical heterogeneities of the processed material and the influence of process parameters and material characteristics of the formation and modification of these heterogeneities, seeking as a result the optimized parameters for the process. We varied three parameters in the process and evaluated the interaction between them. The parameters were modified angle of wire drawing tool (spinneret), the angle of straightening and polishing rolls (PERC) and the placement of coating titanium carbo-nitride (TiCN) in the core of the wire drawing tool (spinneret). We performed characterization of steel, such as microstructure, chemical composition and microhardness. The surface residual stresses of the samples were characterized using the method of X-ray diffraction. After evaluation of surface residual stresses, we analyzed the variation of stress with depth by the method of blind hole (hole-drilling), Classification of inclusions was according to the microscopic method ("worst fields") of ASTM E45 -97, made more severe by analyzing the material found randomly through scanning with microscope on its surface. The results obtained allow us to know the combination of angle stringer and straightening by rollers (PERC) more favorable to generate low levels of residual stresses. In addition to the angle, we found that the geometry of the areas of wire drawing tool (spinneret) influence the levels of residual stress after wire drawing. The core of the spinneret clad in all tests had lower levels of residual stress, proving to be an important condition for the optimization of the process mainly to the reduction of tensile stress after wire drawing.

This study developed a nonlinear constitutive model for a sustainable orthotropic material. Existing methods for constitutive models of wood were improved upon to include the nonlinear stress-strain response not only in the two orthogonal axes but at any orientation to the strong axis of the material. This method also simplifies the nonlinear stress-strain relationships into bilinear stress-strain curves which can be valuable in hand calculations as well as finite-element analyses. The effectiveness of the proposed constitutive model is demonstrated by comparing bilinear stress-strain predictions to experimental data.

Many problems of management of irrigated soils require a knowledge of the soil moisture status and its relationship to plant growth before they can be solved.

The relational processes of sacrifice and self-care both influence every human relationship and as such, every human has to learn how to engage in them. Families are one of the many communities in which one must address sacrifice and self-care. This study provides a qualitative exploration of the relational processes of sacrifice and self-care among a sample of 198 highly religious (Abrahamic faiths) families. In-depth analyses explored motivations, types, and related family processes among family relationships. Five themes from the data about how families perceived and addressed the relational processes of sacrifice and self-care are discussed: (1) tensions between sacrifice and self-care, (2) motivations of sacrifice and/or self-care, (3) types of sacrifice, (4) types of self-care, and (5) processes in faith and family relationships. The ways that participants discussed struggling to address these processes are discussed along with why these ideas are important for marriages and families.