Os sistemas que elevam os eixos dos veículos comerciais foram inicialmente desenvolvidos com o objetivo de economizar pneus. Até o final da década de 90, o uso destes sistemas era restrito, não causando um efeito estatístico sensível na segurança veicular. Devido a um acordo entre concessionárias rodoviárias e o governo, os veículos comerciais pagam nas praças de pedágio o valor correspondente ao número de eixos em contato com o solo naquele momento, minimizando as tarifas dos veículos que fazem uso deste sistema. Esta prática se difundiu rapidamente e poucos estudos técnicos foram realizados focando sua influência na segurança veicular. A elevação dos eixos altera de forma significativa a margem de estabilidade do veículo e a distribuição ideal das forças de frenagem, podendo elevar os riscos de acidentes. Este trabalho consiste num estudo aprofundado do desempenho dos veículos comerciais com estes sistemas de elevação de eixos, sob o ponto de vista técnico e operacional, focando a segurança veicular. Para tanto, são utilizados como metodologia modelos matemáticos já desenvolvidos na literatura científica em veículos exemplos. Parâmetros como a margem de estabilidade, gradiente de esterçamento, eficiência da frenagem dentre outros são analisados; também os efeitos na resposta direcional durante o período transitório em manobras e nos instantes iniciais da frenagem. As influências da elevação dos eixos são analisadas conforme normas e requisitos estabelecidos pela ABNT e ECE R13, inclusive anexo 10, pois a prática da elevação dos eixos pode estar infringindo requisitos impostos por estas normas. Como conclusão é visto que o levantamento dos eixos é prejudicial ao desempenho dinâmico do veículo. Em virtude disto, o seu uso deveria ser fundamentado tanto nas fases conceitual e de desenvolvimento quanto na legislação vigente no país. / The systems that elevate the axles of the commercial vehicles were initially developed with the objective of saving tires. The use of these systems was restricted, not causing a notable statistical effect in the vehicle safety. Due to an agreement between road concessionaires and the government, the commercial vehicles pay toll value according to the number of axles in contact with the soil on that moment, minimizing the taxes of the vehicles using this system. This practice was diffused quickly and few technical studies were accomplished focusing its influence in the vehicle safety. The elevated axles alters in a significant way the vehicle static margin of stability and the ideal distribution of the braking forces, increasing the accident risks. This work consist in deepened studies of the commercial vehicles with these systems of elevation of axles, of the technical and operational point of view, focusing the vehicle safety. For this is used as methodology mathematical models developed already in the scientific literature in vehicles examples. Parameters as the margin of stability, steer gradient, braking efficiency and others are analyzed. Likewise, the effects in the directional response during the transient maneuvers and in the initial instants of the braking. The influences of the elevation of the axes are analyzed according to norms and established requirements for ABNT and ECE R13, including annex 10, because the practice of the elevation of the axes can be infringing requirements imposed by these norms. As main conclusion these systems are prejudicial to vehicle dynamics and handling and its use could be anticipated in conceptual and design phase and in brazilian transport laws.

No presente trabalho realizamos uma análise das lâminas líticas polidas produzidas pelos habitantes pré-históricos no território brasileiro, provenientes de diferentes regiões, grupos e modos de vida. A partir do estudo de coleções arqueológicas e de experimentações pretendemos compreender melhor as diferenças e semelhanças apresentadas por estas lâminas polidas em cada região e sua resistência a testes de impacto em laboratório. Foram analisados 926 artefatos, entre lâminas, fragmentos e alguns percutores. São peças que integram coleções de museus centrais em diferentes regiões do Brasil (Norte, Nordeste, Sudeste e Sul). São principalmente coleções antigas, que apresentam objetos provenientes de diversas partes de cada um dos estados, possibilitando uma cobertura territorial ampla. A despeito dos parcos dados de procedência das peças foi possível caracterizálas regionalmente de forma bastante clara, demonstrando que morfológica e tecnologicamente há variações significativas de uma região para a outra. Em alguns casos foi possível ir ainda mais longe, permitindo propor atribuições culturais a determinados tipos, relacionando-os a algumas Tradições Arqueológicas. No entanto, se tornou evidente também que a partilha dos modos de fazer regionais tem importância capital, que quase sempre vai além das escolhas culturais de um grupo específico. Os trabalhos experimentais (de compressão e impacto) evidenciaram a força necessária para a fragmentação de uma lâmina de basalto de tamanho intermediário, durante seu uso no corte, bem como permitiu estimar a força utilizada por um lenhador mediano, possibilitando compreender melhor algumas relações entre força de impacto, quebras e formas de encabamentos. Finalmente, conseguimos lançar luz sobre a importância das lâminas, tanto para as sociedades do passado, quanto para os arqueólogos do presente, mostrando-as como ferramentas importantes para a compreensão dos modos de vida e dos processos de ocupação do território. / In the present work, we performed an analysis of lithic polished blades produced by the prehistoric inhabitants of the Brazilian territory, from different regions, groups and ways of life. From the study of archaeological assemblages and of experimental archaeology we aim to better understand the differences and similarities presented by these polished blades in each region and their resistance to impact tests. We analyzed 926 artifacts, including blades, fragments and some hammerstones. These items integrate collections of central museums in different regions of Brazil (North, Northeast, Southeast and South). The collections were formed mostly from the middle of the XX century on and present objects from different parts of each of the states, making possible a wide territorial coverage. Despite the scarce data provenance for the pieces it was possible to characterize them regionally quite clearly, showing that morphologically and technologically there are significant variations from one region to another. In some cases it was possible to go even further, allowing the proposition of some cultural attributions to certain types of artifacts, relating them to some Archaeological Traditions. However, it also became clear that sharing the ways of doing things has a major role importance, which often goes beyond the cultural choices of a specific group. The experimental work (of compression and impact) revealed the force required to break a basalt blade of average size during its use in chopping, and allowing us to estimate the force used by an average lumberjack, then enabling a better understanding of some relationships between impact force, breakages and forms of hafting. Finally, we shed light on the importance of the blades, both for past societies, as to the present day archaeologists, showing them as important tools for understanding the ways of life and the processes involved in the human occupation of the territory.

Cette thèse propose conjointement d’étudier l’activité de grimpeurs en escalade glacière tout en développant des perspectives pour la conception. Pour cela, elle s’appuie sur un programme de recherche empirique d’anthropologie cognitive énactif et un programme de recherche technologique ergonomique d’évaluation des situations d’appropriation. La première partie de ce travail s’attache à décrire la construction de « l’objet piolet » en faisant le lien entre innovation et pratique tout en déterminant la relation entre pratiquant et objet technique afin de construire les bases d’une « pensée de la technique » nécessaire à la constitution d’un programme de recherche technologique pour la conception. La deuxième partie poursuit une visée a) épistémique en produisant des connaissances sur le rôle de médiation joué par les piolets dans l’activité des glaciéristes, et b) transformative, en développant la situation d’appropriation comme objet de conception. Pour ce faire, nous mettons en avant a) l’utilisabilité des objets techniques (étude 1) puis b) l’appropriabilité de ces derniers (étude 2) pour ensuite c) mettre en oeuvre l’objet théorique cours d’in-formation en exploitant des données issues de l’activité soumise et non soumise à la conscience pré-réflexive pour documenter l’appropriation (étude 3). La troisième partie, quant à elle, poursuit une visée transformative et s’attarde à définir des critères pertinents pour développer le programme de recherche et enrichir la conception. / The aim of the present thesis is twofold: first, it gives an overview onice climbers’ activity, based on an enactive empirical research program of cognitive anthropology, while developing a technological research program toevaluate appropriation situations and perspectives for design. The first part of this work focuses on the link between innovation and practice while identifying the relationship between the climbers and the technical object in order to build a technological research program focusing on the appropriation of objects. The second part is an epistemic work inculding two steps: a) to produce knowledge on the mediation role of ice axes for novice climbers and b) to develop design objects for the improvement of the research program. To this end, the usability of artifacts is highlighted (study 1) as well as the appropriability of artifacts (study 2) and then c) the theoretical object course of information is implemented using data from the activity subject and non-subject to pre-reflective consciousness to document the appropriation (study 3). The third section, however, seeks to bring about change and focuses to define the relevant criteria for the research program development and to improve the design.

Fibromyalgia (FM) is a chronic pain syndrome of unknown etiology. It was previously suggested that patients with fibromyalgia were, in early life, often subjected to either psychological or physiological trauma. It is, in general, known that early life experiences and attachment to primary caregivers can influence physiological function in adult life, especially those functions related to stress vulnerability. Many studies have been performed on fibromyalgia patients but most of them investigated either psychological or physiological aspects. The purpose of this study was to investigate the psychological profile (attachment style, preferred way of thinking as well as prevalence of depression and anxiety) and physiological aspects (autonomic nervous system function and cortisol levels) simultaneously in an attempt to see whether a link exists between the two aspects and whether a specific psychoneurological profile could be discerned for fibromyalgia patients. Sixteen patients (14 females, 2 males) with fibromyalgia, and 15 age- and sex-matched controls (13 females, 2 males) were studied. Patients were diagnosed according to the American College of Rheumatology (ACR, 1990) criteria for fibromyalgia. The Patient Health Questionnaire gathered information on the patient’s past health problems, operations, accidents and the prevalence of traumatic events. The Fibromyalgia Impact Questionnaire and Review of Current Symptoms Questionnaire were completed to assess the severity of the disorder. The Experiences in Close Relationships – Revised Questionnaire determined attachment styles. Hemisphere dominance (preferred way of thinking) was evaluated by the Herrmann Brain Dominance Instrument (HBDI), heart rate variability (HRV) by recording R-R intervals and calculating time and frequency domain parameters and salivary cortisol levels by ELISA. Significant differences were seen between patients and controls for cortisol levels; the total number of symptoms; the number of adverse events in lifetime; anxiety and avoidance subscales of the ECR-R; FIQ total scores; and scores for scales within the FIQ. R-R spectral analysis revealed distinct lowered overall HRV in patients. An orthostatic test revealed a weakened shift towards sympathetic dominance upon standing. During a psychological stressor (filling out the ECR-R), the patients’ autonomic nervous system failed to respond with lower HRV as with the controls. As far as the hemispheric dominance of the patients was concerned, the majority appeared to be right-brain orientated with thinking styles preferences strongly influenced by limbic functions. Preference for thinking styles influenced by right limbic structures increased during stress. A link existed between anxiety and depression and the severity of the fibromyalgia symptoms. The results of individual psychological and physiological parameters found in this study are largely in concordance of that of other studies. Significant differences exist between the psychoneurological variables of fibromyalgia patients and healthy controls: The patient group in this study were characterised by a high prevalence adverse events, insecure attachment styles, high emotionality in the absence of rationality, multiple somatic symptoms, and altered stress-axes activity reflected in low HRV, an inability to mount an appropriate sympathetic response to acute stressors and elevated baseline cortisol levels. It can be concluded that fibromyalgia patients in the present study presented with a distinct psychoneurological profile. / Dissertation (MSc (Physiology))--University of Pretoria, 2007. / Physiology / unrestricted

Ce travail de thèse concerne l'articulation trapézométacarpienne. La première partie du travail a concerné l'étude de la morphogénèse de l'arche palmaire par modélisation géométrique 3D. Cinq embryons ont été utilisés. Les résultats de cette étude montre le caractère asymétrique et l'opposition précoce du pouce chez l'embryon humain. La deuxième partie a consisté à partir d'un protocole IRM spécifique sur 5 sujets sains à déterminer la cinématique 3D de l'articulation trapézo-métacarpienne en utilisant les axes hélicoïdaux. La troisième partie, suivant le même protocole sur sujets pathologiques à partir d'image scanner a permis d'évaluer l'effet des différents types de traitement en cas de rhizarthrose. Les résultats trouvent leur application dans l'évaluation quantitative des pathologies de l'articulation trapézo-métacarpienne ainsi que dans le développement des prothèses. / This work concerned the first carpo-metacarpal joint. The first part of this work was the study of the morphogenesis of the palmar arch using three-dimensional geometrie modeling. Five embryos were used for this study. The results of this study support the hypothesis that opposition and asymmetry of the thumb appears early in embryological development. In the second part, with specifie MRI protocol on 5 normal subjects, the objective was to quantify the 3D motion of the trapezo-metacarpal joint using helical axes theory. In the last part, using the same protocol on pathological subjects (CT scan images), the objective was to evaluate the effect of different type of treatment of the first carpo­ metacarpal arthritis.The results of the work are of interest for the quantitative evaluation of pathological trapezo-metacarpal joint and in the development of prosthesis.

The content of this master’s thesis is the choice of a suitable concept for the multifunctional machining center for rotary and non-rotating workpieces and design and processing of one structural node of this machine. The structure of the work is divided into three parts. In the first part, the market analysis is carried out from which it follows to the second part and it is the choice of a suitable machine concept. The third part deals with its own design of the constructional structure of this machining center.

The aim of this thesis is design of deburring machine, focusing on the headstock, capable of aligning the front side and chamfering at the round bars. At the beginning is a short research design nodes, used in the construction of machine tools. As part of the work was done and the measurement of cutting forces to determine the load while standing. Work also includes a series of calculations to justify the use of selected components. The outcome of the work is also a 3D model.

Dans le domaine de la fabrication additive plusieurs technologies cohabitent et présentent des maturités et des applications différentes : le lit de poudre, la projection de poudre et le dépôt de fil pour ne citer que les principales. Nous avons étudié, dans le cadre de cette thèse, la réalisation de pièces de grandes dimensions du domaine aéronautique en alliage d’aluminium, par technologie WAAM (Wire Arc Additive Manufacturing) robotisée. Cette technologie repose sur l’utilisation un générateur de soudure à l'arc, d’un système de protection gazeuse et d’un système d'alimentation en métal d'apport sous forme de fil. Pour répondre à cette problématique, plusieurs voies de recherche ont été investiguées. La première traitait principalement de la génération de trajectoires : Plusieurs expérimentations ont permis de montrer l’intérêt et l’importance de la génération de trajectoires et notamment la maitrise de l’orientation outil pour la fabrication additive de pièces complexes en étudiant le respect de la géométrie souhaitée. La seconde concernait l’étude de la santé matière des pièces fabriquées. Des observations au niveau de la microstructure, mais aussi des caractéristiques mécaniques ont permis de mettre en évidence l’influence des paramètres opératoires sur la qualité de la matière déposée. Enfin, la réalisation de pièces fonctionnelles dans le cadre d’un projet financé par la DGA/DGAC et dont les partenaires étaient : STELIA, CONSTELLIUM, CT INGENIERIE et l’Ecole Centrale de Nantes, a permis de mettre en avant l’intérêt du procédé pour la fabrication de pièces aéronautiques. Un élément de structure aéronautique composé de raidisseurs a été fabriqué avec le procédé WAAM sur un substrat double courbure en alliage aluminium. Les difficultés accrues de réalisation ont pu être levées par l'emploi de la méthodologie développée dans le cadre de la thèse. / In the field of additive manufacturing (AM), several processes are present and have different applications and levels of development: the main technologies are powder-bed based AM, powder projection and Wire Additive Manufacturing (WAM). We have studied, in this PhD work, the manufacturing of large scale components in aluminum alloy for aircraft industry with Wire Arc Additive Manufacturing (WAAM). This technology is based on a welding generator, a shielding gas protection and a feedstock (wire in this case). To solve this issue, several ways of research were investigated. The first one dealt with toolpath generation: several experiments have highlighted the importance of tool path generation and the tool orientation to manufacture complex parts and improve the part accuracy. The second one was about the validation of the material quality after deposit. Microstructural observations and mechanical tests have demonstrated the effect of process parameters on the deposit quality. Finally, in the context of a DGA/DGAC funded research project, whose partners were STELIA, CT INGENIERIE, CONSTELLIUM and l’Ecole Centrale de Nantes, the manufacturing of functional part in aluminum alloy has shown the interest of the process for aircraft industry. A structural component based on a double curvature geometry has been manufactured with WAAM. The methodologies developed in this PhD work have enabled us to solve the issues to manufacture that type of component.

Den här studien är en utforskning av dubbeleggade miniatyryxor av bärnsten som hittas i neolitiska gravar. Tre gravplatser har presenterats: ett flatmarksgravfält i Borgeby, flatmarksgravar i Ajvide på Gotland, och tre gånggrifter i Danmark. Dubbeleggade miniatyrer av bärnsten hittas i alla. Genom att använda praktikteori och begreppet habitus är syftet att uppsatsen ska ge insikt i varför miniatyrerna uppträder i Borgeby, och vad de kan ha haft för betydelse i samhället. En komparativ metod har använts för att jämföra gravplatserna, för att undersöka om det finns några likheter eller skillnader mellan dem. Resultatet visar att människorna i Borgeby hade kontakter med omvärlden. Bärnstenen var importerad från Danmark eller inspirerad av den danska trattbägarkulturen, och gravskicket i sig är inspirerat av den gropkeramiska kulturens gravar. / The study is an examination of double-edged miniature amber axes found in neolithic graves. Three different gravesites stand at the center of the essay: a flat grave field at Borgeby in Skåne, flat graves at Ajvide on Gotland, and three different megalithic passage graves in Denmark. Double-edge miniatures in amber appear in all of them. Using practice theory and the conceptof habitus the essay aims to give an insight in why they appear at Borgeby, as well as what double-edged axes might have meant to the people depositing them in graves. A comparative analysis of the above-mentioned gravesites will also be made, to examine whether any obvious similarities or differences exist between them. The results show that people in Borgeby had connections to the surrounding world. The miniature amber objects seem to be imported from Denmark or inspired by Danish shapes, whereas the graves themselves seem to be inspired by pitted ware culture.

Biomechanics, an emerging science, refers to the mechanical characterization of biological tissues. Recent work published in this field demonstrate the role of mechanical processes and properties on the biological tissues functionalities, and especially at the microscopic scale (cell biomechanics). Biomechanical data acquisition is however quite challenging. This requires appropriate measurement tools (for forces, strain, ...) to cope with the biological sample and environment constraints (biocompatibility, size, anisotropy, ...). In parallel, the fast developments observed these last years in microtechnologies lead to interesting research possibilities. The family of MEMS [MicroElectroMechanical Systems] devices for instance introduces a new potential of interaction with the microscopic world. The integration of this technology in the field of cellular biomechanics is thus a natural choice. In that context, this work aims to design a 3-axis microforce sensor to measure biological tissues deformations at the microscopic scale. The MEMS device, fabricated on SOI [Silicon on Insulator] wafers, is based on piezoresistive and capacitive force transductions. It can be used as an actuator at least in one direction. This thesis describes the design, fabrication and test of the 3-axis system. A 1-axis prototype, exclusively capacitive, is first realized and acts as the foundation of the 3-axis device. The 1-axis force sensor, tested on the [0 ? 350[mu]N ] range shows a sensitivity in the order of 4.85mV/[mu]N (G=2000) and a resolution of 1.24[mu]N (linearity until 100[mu]N ). A new 3-axis geometry is then proposed to improve the direction decoupling efficiency of 2-axis capacitive sensors presented in publications and add a third detection axis. The decoupling is achieved using a"two frames" geometry and piezoresistors implanted in a configuration only sensitive to an out-of-plane loading. The three transducers performances are analysed individually. Tested on a range of 250? N , the sensors show a linear behaviour on the whole forces domain in the out-of-plane axis (piezoresistors) and until 100[mu]N in the in-plane direction (electrostatic combs). The piezoresistive and capacitive transducers are characterized by sensitivities of 0.93mV/[mu]N (g=400) and 6.35mV/[mu]N (G=500) respectively (on the linear part), with resolutions of 7[mu]N and 0.161[mu]N. The dynamical behaviour of the sensor allows its use above the kHz. The cross-talk sensitivities of each transducer are evaluated to 1-5% of their axis sensitivity (decoupling). The work presented in this thesis demonstrates the feasability of a 3-axis MEMS force sensor based on capacitive (in-plane sensing) and piezoresistive (out-of-plane sensing) detection. The proof of concept refers to the fabrication and performances (sensitivity, resolution, decoupling) of the proposed design.