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Denna studie undersökte hur smartklockors gränssnitt kan utformas för att upplevas användbara samt bidra till minimal kognitiv belastning under fysisk aktivitet. Smartklockors skärmar ställer andra krav på gränssnittet samt medför ett antal utmaningar för hur information kan presenteras på bästa sätt. Utöver detta brukar smartklockor användas i samband med fysisk aktivitet, som ställer höga krav på användarens uppmärksamhet. För att bibehålla hög kvalitet på träningen bör den kognitiva belastningen minska. För att undersöka detta har Cognitive Load Theory applicerats för att kunna optimera arbetsminnets kapacitet. Studien gjorde på personer i 20 års ålder. En kvalitativ datainsamling gjordes genom ett användartest och semistrukturerade intervjuer. Användartestet utfördes på en stationär cykel där deltagarna utförde ett antal uppgifter på en smartklocka. Efteråt skedde semistrukturerade intervjuer. Resultatet analyserades genom kategorisering och jämfördes med tidigare studier. Utifrån de mest förekommande resultaten skapades åtta designförslag. Resultaten visade att eliminering av viss information på gränssnitt kan minska den kognitiva belastningen samt höja användbarheten. Ett konsekvent gränssnitt skulle kunna minimera antal fel samt underlätta för användaren att korrigera fel. En tillämpning av de framtagna designförslagen kan eventuellt minimera den kognitiva belastningen vid interaktion med smartklockors gränssnitt vid fysisk aktivitet. Detta kan underlätta för användaren att fokusera på träningen samt uppleva klockan som mer användbar. / This study examined how an interface for smartwatches can be designed to be perceived as useful and reduce cognitive load during physical activity. Smartwatch screens have other demands on the interface and face several challenges regarding how information can be presented. In addition to this, smartwatches are often used in physical activity, which places high demands on user's attention. To maintain high-quality training, the cognitive load should be reduced. To investigate this, cognitive load theory has been applied to optimize the capacity of the working memory. The study looked at people in their 20s. Qualitative data collection was done through a user test and semi-structured interviews. The user test was done on a stationary bike, the participants performed several tasks on the smartwatch. The participants rode a stationary bicycle while performing tasks on a smartwatch, followed by semistructured interviews. The results were analyzed by thematization and compared with previous studies. Based on the most common results, eight design proposals were created. The results showed that by eliminating unnecessary information, the interface can reduce cognitive load and increase usability. A consistent interface could minimize the number of errors and make it easier for the user to correct errors. An application of the developed design proposals may minimize the external load when interacting with the smartwatch interface during physical activity. This can support users can focus on training and experience the watch as more useful.

With the advancement of sensor technology and data processing capacities, various types of high volume data are available for process monitoring and prognostics in manufacturing systems. In a broaching process, a multi-toothed broaching tool removes material from the workpiece by sequential engagement and disengagement of multiple cutting edges. The quality of the final part, including the geometric integrity and surface finish, is highly dependent upon the broaching tool condition. Though there has been a considerable amount of research on tool condition monitoring and prognostics for various machining processes, the broaching process is unique in the following aspects: 1) a broaching process involves multiple cutting edges, which jointly contribute to the final part quality; 2) the resharpening and any other process adjustments to the tool can only be performed with the whole broaching tool or at least a whole segment of the tool replaced. The overarching goal of this research is to explore how engineering knowledge can be used to improve process monitoring and prognostics for a complex manufacturing process like broaching. This dissertation addresses the needs for developing new monitoring and prognostics approaches based on various types of data. Specifically, the research effort focuses on 1) the use of in-situ force profile data for real-time process monitoring and fault diagnosis, 2) degradation characterization for broaching processes on an individual component level based on image processing; and 3) system-level degradation modeling and remaining useful life prediction for broaching processes based on multiple images. / Ph. D.

Afrikaans text / Die doel van hierdie studie was om vas te stel of musiek in terapie gebruik kan word deur ' opvoedkundige sielkundiges, asook wat die verskil is tussen musiekterapie en die terapeutiese aanwending van musiek deur ander terapeute. Vir die verkenning van die terapeutiese gebruik van musiek is 'n literatuurstudie gedoen oor die fenomeen musiekterapie, asook oor die terapeutiese gebruik van musiek. Die twee verskynsels is met mekaar vergelyk om ooreenkomste en verskille aan te dui. Die empiriese studie het aan die lig gebring dat musiek op baie verskillende maniere in terapie gebruik kan word en gekombineer kan word met ander hulpmiddels. Die emosionele en kognitiewe funksie wat musiek vervul is met die studie uitgewys. Musiek help byvoorbeeld om 'n emosionele klimaat te skep wat effektief in terapie gebruik kan word; en musiek kan 'n mens se denke stimuleer. Aanbevelings is ook gegee vir die terapeutiese gebruik van musiek. / The object of the study was to determine if and how music can be used in therapy by the educational psychologist. The further aim was to determine the difference between music therapy and the therapeutic application of music by other therapists. In the exploration of the therapeutic use of music, a comparative study was done between music therapy as phenomenon and the therapeutic use of music, where similarities and differences were outlined. The empirical study showed that music can be used in different ways in therapy and can also be combined with other therapeutical aids. According to this study, music can fulfill an emotional and a cognitive roll. A pleasant emotional climate for therapy can be created and stimulate the client's thoughts. With this study it was possible to give guidelines for therapeutic applications of music. / Psychology of Education / M. Ed. (Voorligting)

La disponibilité élevée des systèmes technologiques comme l'aérospatial, la défense, la pétrochimie et l'automobile, est un but important des nouveaux développements de la technologie de conception des systèmes sachant que la défaillance onéreuse survient, en général, soudainement. Afin de rendre les stratégies classiques de maintenance plus efficaces et pour prendre en considération l'état et l'environnement évolutifs du produit, un nouveau modèle de pronostic analytique est développé en tant que complément des stratégies de maintenance existantes. Ce nouveau modèle est appliqué aux systèmes mécaniques soumis à la défaillance par fatigue sous charge cyclique répétitive. Sachant que l'effet de fatigue va initier des microfissures qui peuvent se propager soudainement et conduire à la défaillance. Ce modèle est basé sur des lois d'endommagement existantes dans la mécanique de la rupture comme la loi de propagation de fissures de Paris-Erdogan à côté de la loi de cumul de dommage de Palmgren-Miner. A partir d'un seuil prédéfini de dégradation DC, la durée de vie résiduelle (RUL) est estimée à l'aide de ce modèle de pronostic. Les dommages peuvent être cumulés linéairement (Loi de Palmgren-Miner) et aussi non linéairement afin de prendre en compte un comportement plus complexe des chargements et des matériaux. Le modèle de dégradation développé dans ce travail est basé sur une sommation d'une mesure de dommage D à la suite de chaque cycle de chargement. Quand cette mesure devient égale à un seuil prédéfini DC, le système est considéré dans l'état de panne. En plus, l'influence stochastique est incluse dans notre modèle pour le rendre plus précis et réaliste. / The high availability of technological systems like aerospace, defense, petro-chemistry and automobile, is an important goal of earlier recent developments in system design technology knowing that the expensive failure can generally occur suddenly. To make the classical strategies of maintenance more efficient and to take into account the evolving product state and environment, a new analytic prognostic model is developed as a complement of existent maintenance strategies. This new model is applied to mechanical systems that are subject to fatigue failure under repetitive cyclic loading. Knowing that, the fatigue effects will initiate micro-cracks that can propagate suddenly and lead to failure. This model is based on existing damage laws in fracture mechanics, such as the crack propagation law of Paris-Erdogan beside the damage accumulation law of Palmgren-Miner. From a predefined threshold of degradation DC, the Remaining Useful Lifetime (RUL) is estimated by this prognostic model. Damages can be assumed to be accumulated linearly (Palmgren-Miner's law) and also nonlinearly to take into consideration the more complex behavior of loading and materials. The degradation model developed in this work is based on the accumulation of a damage measurement D after each loading cycle. When this measure reaches the predefined threshold DC, the system is considered in wear out state. Furthermore, the stochastic influence is included to make the model more accurate and realistic.

La mise en place d’une politique de maintenance prévisionnelle est un défi majeur dans l’industrie qui tente de réduire le plus possible les frais relatifs à la maintenance. En effet, les systèmes sont de plus en plus complexes et demandent un suivi de plus en plus poussé afin de rester opérationnels et sécurisés. Une maintenance prévisionnelle nécessite d’une part d’évaluer l’état de dégradation des composants du système, et d’autre part de pronostiquer l’apparition future d’une panne. Plus précisément, il s’agit d’estimer le temps restant avant l’arrivée d’une défaillance, aussi appelé Remaining Useful Life ou RUL en anglais. L’estimation d’une RUL constitue un réel enjeu car la pertinence et l’efficacité des actions de maintenance dépendent de la justesse et de la précision des résultats obtenus. Il existe de nombreuses méthodes permettant de réaliser un pronostic de durée de vie résiduelle, chacune avec ses spécificités, ses avantages et ses inconvénients. Les travaux présentés dans ce manuscrit s’intéressent à une méthodologie générale pour estimer la RUL d’un composant. L’objectif est de proposer une méthode applicable à un grand nombre de cas et de situations différentes sans nécessiter de modification majeure. De plus, nous cherchons aussi à traiter plusieurs types d’incertitudes afin d’améliorer la justesse des résultats de pronostic. Au final, la méthodologie développée constitue une aide à la décision pour la planification des opérations de maintenance. La RUL estimée permet de décider de l’instant optimal des interventions nécessaires, et le traitement des incertitudes apporte un niveau de confiance supplémentaire dans les valeurs obtenues. / Predictive maintenance strategies can help reduce the ever-growing maintenance costs, but their implementation represents a major challenge. Indeed, it requires to evaluate the health state of the component of the system and to prognosticate the occurrence of a future failure. This second step consists in estimating the remaining useful life (RUL) of the components, in Other words, the time they will continue functioning properly. This RUL estimation holds a high stake because the precision and accuracy of the results will influence the relevance and effectiveness of the maintenance operations. Many methods have been developed to prognosticate the remaining useful life of a component. Each one has its own particularities, advantages and drawbacks. The present work proposes a general methodology for component RUL estimation. The objective i to develop a method that can be applied to many different cases and situations and does not require big modifications. Moreover, several types of uncertainties are being dealt With in order to improve the accuracy of the prognostic. The proposed methodology can help in the maintenance decision making process. Indeed, it is possible to select the optimal moment for a required intervention thanks to the estimated RUL. Furthermore, dealing With the uncertainties provides additional confidence into the prognostic results.

Um grande número de rochas de granulação grosseira tem valor agregado muito alto quando usadas como materiais de construção, as chamadas rochas exóticas. No entanto, existem problemas com a utilização desses materiais dado a sua fragilidade, que está relacionada com a sua textura muito heterogênea. No Brasil é empregado empiricamente um reforço (compósito) que utiliza resina epóxi e fibra de vidro para melhorar o desempenho mecânico de tais rochas quando empregadas como materiais de construção. Os objetivos da presente pesquisa foram estudar o reforço tradicional brasileiro (telagem) para determinar sua eficiência e, ao mesmo tempo, propor outras soluções de reforço alternativas e mais eficientes, e avaliá-las através da caracterização mecânica experimental. Foi proposto um critério denominado Declive Global para avaliar as tensões de serviço dos materiais pegmatíticos estudados, quando os reforços propostos foram aplicados. Para validar esse critério foi utilizado um sistema de correlação digital de imagem (CDI) para observar e medir o comportamento de deformação e fratura durante a realização de testes de flexão em 4 pontos. Tanto o critério proposto como a CDI mostraram que a propagação de fissuras ocorre muito antes do material atingir a carga máxima. O reforço alternativo proposto, que emprega resina epóxi e uma fibra de vidro 600 g/m² apresentou o melhor desempenho mecânico, elevando a carga de ruptura até 6x em comparação com as amostras onde nenhum reforço foi aplicado. Os resultados demonstrados pelos reforços propostos são promissores e aumentam a possibilidade de aplicar rochas exóticas frágeis como materiais de construção, além do critério proposto fornecer uma ferramenta importante para a compreensão mecânica prévia de produtos de rocha que utilizam reforços compósitos. / A great number of coarse-grained natural stones have very high added-value when used as building materials, the so called exotic stones. However, problems using these materials arise from its brittleness behavior, which are related to its very heterogeneous texture. Glass fiber-reinforced epoxy composite (GFRC) is being used to improve mechanical performance of such stones when employed as building materials. The objectives of this present investigation it were studying the Brazilian traditional reinforcement to determinate its efficiency and, at the same time, a number of alternative solutions were proposed and evaluated through experimental mechanical characterization. It was proposed a slope-based criterion to evaluate the useful service loads of pegmatitic materials when glass fiber-reinforcement is applied. To validate the proposed criterion, a digital image correlation (DIC) system was employed to observe and measure strain and fracture behavior during the realization of 4-point bending tests. Both proposed criterion and DIC show that crack propagation occurs long before the material reaches maximum load. GFRC acts as a crack inhibitor, raising the breaking load up to 6x in comparison with the specimens where no reinforcement was applied. The results from this study enhance the capability to apply such materials as building materials and provide an important tool to perform prior mechanical understanding of stone products using GFRC.

Esse estudo investigou se as notas explicativas às demonstrações financeiras, preparadas de acordo com as International Financial Reporting Standards (IFRS), cumprem seu objetivo principal de fornecer informações úteis a investidores e credores no mercado brasileiro. A análise foi desenvolvida a partir de dados obtidos junto a usuários externos, investidores e credores, de informações financeiras divulgadas em notas explicativas às demonstrações financeiras de companhias abertas brasileiras, listadas na BM&FBovespa, no período de 1º de outubro de 2013 a 28 de fevereiro de 2014. Foram identificadas, também, as opiniões de preparadores de informações financeiras e contrapostas às dos usuários externos quanto às características da informação financeira útil, emanadas do The Conceptual Framework for Financial Reporting IASB (2010); foi ainda analisada a influência do processo adotado pelo IASB para definir requerimentos de divulgação incluídos em suas normas e pronunciamentos contábeis associado à confiabilidade trazida por auditores independentes (Big four) quanto ao enforcement à aderência a esses requerimentos, no âmbito da utilidade da informação financeira. De forma geral, os resultados indicaram que as notas explicativas às demonstrações financeiras atingem parcialmente seu objetivo principal de fornecer informações úteis a investidores e credores no mercado brasileiro, uma vez que preparadores da informação financeira norteiam-se pelos requerimentos de divulgação definidos nos IFRS de forma bastante literal, inclusive com auxílio de disclosure check list, propiciando a inclusão de informações imateriais em notas explicativas devido à ausência de orientação específica sobre determinação de materialidade nas normas do IASB. / In this study we have examined whether the explanatory notes to financial statements prepared in accordance with International Financial Reporting Standards (IFRS) achieve their main objective of providing useful information to investors and creditors in the Brazilian market. The analysis was based on data obtained from external users, investors and creditors with respect to financial information disclosed in the explanatory notes of financial statements of Brazilian public companies listed on the BM&FBovespa, during the period from October 1, 2013 to February 28, 2014. It was identified the opinions of the preparers of financial information and compared them with those of external users regarding the characteristics of useful financial information described in The Conceptual Framework for Financial Reporting IASB (2010). It was also analyzed the influence of IASB´s process to define the disclosure requirements in their accounting standards and pronouncements, together with the reliability resulting from independent auditors (Big Four) regarding the enforcement of compliance with these requirements, as they relate to the usefulness of financial information. Overall, the results revealed that the explanatory notes to the financial statements partially achieve their main goal of providing useful information to investors and creditors in the Brazilian market, since preparers of financial information are guided by the disclosure requirements defined in the IFRS quite literally, sometimes with the assistance of a disclosure checklist, resulting in the inclusion of immaterial information in the notes, due to the lack of specific guidance in the IFRS regarding materiality.