Made available in DSpace on 2015-04-22T22:18:39Z (GMT). No. of bitstreams: 1 Dissertacao-Maria Celia Santiago.pdf: 6521057 bytes, checksum: 604046726fc45ef6756e780bba447391 (MD5) Previous issue date: 2010-08-26 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / This work examines the metallurgical strike that occurred in August 1985 in Manaus, Amazonas. Its goal was to know and understand how mobilization and organization of amazon workers, protagonists of the most important strike registered in the city. We use a oral history methodology, which enabled us to understand the process of formation of Oposição Sindical Metalúrgica, the conquest of the Union and the organization of workers inside and outside of the factories, which ensured the large membership of workers to the outage. From the registry in memory of some of the leaders of the outage, coverage by the local press, through the materials disseminated by newspapers A Crítica, Jornal do Commércio and A Notícia and other documents found in personal holdings of Union of Metallurgical and other public institutions, could also understand the central role played by the Catholic Church through Comunidades Eclesiais de Base (CEBs) and Pastoral Operária, training policy of the leaders of the movement, in addition to the significant contribution of the Federação de Órgãos para Assistência Social e Educacional (FASE) during the organization of the strike. / Este trabalho analisa a greve dos metalúrgicos ocorrida em agosto de 1985, em Manaus, Amazonas. Seu objetivo foi conhecer e compreender a forma de mobilização e organização dos operários amazonenses, protagonistas da mais importante greve registrada na cidade. Utilizamos como metodologia a história oral, que nos permitiu compreender o processo da formação da Oposição Sindical Metalúrgica, a conquista do sindicato e a organização dos trabalhadores dentro e fora das fábricas, que garantiu a grande adesão dos trabalhadores à paralisação. A partir do registro da memória de algumas das lideranças da paralisação, da cobertura dada pela imprensa local, através das matérias divulgadas pelos jornais A Crítica, Jornal do Commércio e A Notícia e outros documentos encontrados em acervos pessoais, do Sindicato dos Metalúrgicos e de outras instituições públicas, também foi possível perceber o papel central exercido pela Igreja Católica, através das Comunidades Eclesiais de Base (CEBs) e Pastoral Operária, na formação política das lideranças do movimento, além da contribuição significativa da Federação de Órgãos para Assistência Social e Educacional (FASE) durante a organização da greve.

Forced truancy is a risk factor that influences juvenile behavior, requiring the joint efforts of school authorities, parents, and courts to address. It is a phenomenon where students desire attending school, but for reasons beyond their control, they are prohibited from attending classes. Some of these reasons are teachers' strike action, students' poverty, lack of educational infrastructures, and unsafe educational environment. Teachers' strike is a frequent occurrence in southeastern Nigeria caused by irregular payment of teachers' wages, benefits, and other remunerations. This case study of 3 secondary schools in southeastern Nigeria sought to understand the impact of forced truancy by examining the relationship between forced truancy and youth delinquency. Although previous studies have explored the causes of truancy, few studies have addressed the effect of forced truancy created by incessant teachers' strike. The theoretical framework that guided this study included Hirschi's social bond theory and Merton's social structure. Case studies were developed using data from the participants and review of documents. A maximum variation method was used for data collection through semi-structured that resulted in a review of archival records and open-ended interviews with students (S = 9), teachers (T = 8), and principals (SP = 4). Descriptive case analysis were used to identify common themes and patterns using constant comparative techniques. Implications for positive social change include identifying areas that need improvement and recommending to legislators and education policy makers for the best approach to addressing the problem, where it has the potential to eliminate teachers' strike, reduce youth truancy, and improve student's academic performance.

A primary motivation for this research comes from the need to improve the ability of polymer-matrix composites to withstand lightning strikes. In particular, we are concerned with lightning strike damage in composite wind turbine blades. The direct effects of lightning strike on polymer-matrix composites often include rapid temperature rise, melting or burning at the lightning attachment points, and mechanical damage due to lightning-induced magnetic force and acoustic shock wave. The lightning strike damage accumulation problem is essentially multiphysic. The lightning plasma channel discharges an electric current up to 200 kA, inducing a severe heat flux at the surface of the composite structure, as well as generating Joule heating through the composite structure. The resulting electro-thermo-mechanical response of the composite structure may include matrix degradation and decomposition, delamination, and fiber breakage and sublimation, thus leading to catastrophic failure. The existing studies related to the lightning strike damage in composites ignored the lightning channel radius expansion during the initial lightning discharge and lacked adequate treatment of material phase transitions. These assumptions significantly simplify the mathematical treatment of the problem and affect the predictive capabilities of the models. Another common feature of these limited studies is that they all focused on carbon-fiber-reinforced polymer-matrix (CFRP) composites, which are electrically conductive. In the present thesis, the thermal responses and thermal ablations in a non-conductive glass-fiber-reinforced polymer-matrix (GFRP) composite wind turbine blade and in a conductive CFRP composite wind turbine blade are studied, respectively. In the case of non-conductive GFRP composite wind turbine blade, prior to the thermal response and thermal ablation analysis, a finite element analysis is performed to calculate the electric field due to lightning stepped leader to estimate the dielectric breakdown of the non-conductive composite wind turbine blade. The estimation of dielectric breakdown is used to determine whether Joule heating needs to be included in the problem formulation. To predict the thermal response and thermal ablation in the composite structure due to lightning strike, a physics-based model describing surface interaction between the lightning channel and the composite structure has been developed. The model consists of: (i) spatial and temporal evolution of the lightning channel as a function of the electric current waveform; (ii) temporary and spatially non-uniform heat flux and current density (in the case of electrically conductive CFRP composite or if dielectric breakdown occurs in the case of non-conductive GFRP composite) generated at the composite structure; and (iii) nonlinear transient heat transfer problem formulation for layered anisotropic composites that includes the moving boundary of the expanding lightning channel and the phase transition moving boundary associated with instantaneous material removal due to sublimation. The model has been employed to investigate the thermal responses and thermal ablations in a GFRP composite laminated panel used in a Sandia 100-meter all-glass baseline wind turbine blade (SNL 100-00) and a typical CFRP composite laminated panel subjected to lightning strike. The temperature-dependent directional material properties for both the GFRP and CFRP composites have been determined in this thesis using a micromechanics approach based on the experimental data for fibers and resin. An integrated Matlab-ABAQUS numerical procedure features the aforementioned aspects (i), (ii), and (iii) of the developed model. The obtained results include the evolution of temperature fields in the composite laminated panel and the progressive shape change of the composite laminated panel due to thermal ablation. The predictions of thermal ablation in the CFRP composite laminated panel are validated by reported experimental results.

Mathematical modeling and realistic human simulation of human jogging motion is a very challenging problem. Majority of the current literature is focused on studying walking or running. This work is aimed at bridging the gap in literature due to the lack of research work in three main areas: (1) simulations and experiments on running at speeds lower than 3 m/s, (2) Kinetics of fore-foot strike pattern in jogging and running and (3) the existence of a double support phase in running at slower speeds and its effects. Formulations to simulate natural human jogging are studied and developed. The digital human model used for this work includes 55 degrees of freedom, 6 for global translation and rotation and 49 for the revolute joints to represent the kinematics of the body. Predictive Dynamics methodology is used for dynamic analysis where the problem is formulated as a nonlinear optimization problem. Both, displacement and forces are considered as unknowns and identified by solving the optimization problem. The equations of motion are satisfied by applying them as equality constraints in the formulation. Kinematics analysis of the mechanical system is performed using the Denavit-Haretneberg (DH) method. The zero moment point (ZMP) condition is satisfied during the ground contact phase to achieve dynamic stability. The joint angle profiles are discretized using B-spline interpolation method. The joint torque squared, also termed dynamic effort, and the difference between predicted motion and motion capture data are used as performance measures and minimized in the optimization formulation. The formulation also includes a set of constraints to simulate natural jogging motion. Two formulations are discussed for jogging on a straight path: (1) one-step jogging formulation and (2) one-stride jogging formulation. The one-stride formulation is discussed for clock-wise and counter clock-wise jogging along a curved path. Cause and effect is shown by obtaining simulation results for different loading conditions. The proposed formulation provides realistic human jogging motion and is very robust.

The Clark fault is one of the primary dextral faults in the San Jacinto fault zone system, southern California. Previous mapping of the Clark fault at its southern termination in the San Felipe Hills reveals it as a broad right lateral shear zone that ends north of the crossing, northeast-striking, left-lateral Extra fault. We investigate the relationship between the dextral Clark fault and the sinistral Extra fault to determine whether the Clark fault continues to the southeast. We present new structural, geophysical and geomorphic data that show that the Extra fault is a ~7 km wide, coordinated fault array comprised of four to six left-lateral fault zones. Active strands of the Clark fault zone persists through the Extra fault array to the Superstition Hills fault in the subsurface and rotate overlying sinistral faults in a clockwise sense. New detailed structural mapping between the San Felipe and Superstition Hills confirms that there is no continuous trace of the Clark fault zone at the surface but the fault zone has uplifted an elongate region ~950 km. sq. of latest Miocene to Pleistocene basin-fill in the field area and far outside of it. Detailed maps and cross sections of relocated microearthquakes show two earthquake swarms, one in 2007 and another in 2008 that project toward the San Felipe Hills, Tarantula Wash and Powerline strands of the dextral Clark fault zone in the San Felipe Hills, or possibly toward the parts of the Coyote Creek fault zone. We interpret two earthquake swarms as activating the San Jacinto fault zone beneath the Extra fault array. These data coupled with deformation patterns in published InSAR data sets suggest the presence of possible dextral faults at seismogenic depths that are not evident on the surface. We present field, geophysical and structural data that demonstrate dominantly left-lateral motion across the Extra fault array with complex motion on secondary strands in damage zones. Slickenlines measured within three fault zones in the Extra fault array reveal primarily strike-slip motion on the principal fault strands. Doubly-plunging anticlines between right-stepping en echelon strands of the Extra fault zone are consistent with contraction between steps of left-lateral faults and are inconsistent with steps in dominantly normal faults. Of the 21 published focal mechanisms for earthquakes in and near the field area, all record strike-slip and only two have a significant component of extension. Although the San Sebastian Marsh area is dominated by northeast-striking leftlateral faults at the surface, the Clark fault is evident at depth beneath the field area, in rotated faults, in microseismic alignments, and deformation in the Sebastian uplift. Based on these data the Clark fault zone appears to be continuous at depth to the Superstition Hills fault, as Fialko (2006) hypothesized with more limited data sets.

Ce travail s'inscrit dans une problématique de mise en œuvre et d'étude d'un revêtement conducteur polymère extrinsèque pour la protection foudre des structures aéronautiques de type composite polymère renforcé fibres de carbone (CFRP). Le revêtement est composé d'une matrice poly(époxy) haute performance bi-composant fluide à température ambiante et de fils submicroniques d'argent à haut facteur de forme (AgNWs) obtenus par un procédé polyol. Une attention particulière a été portée à l'étude de l'influence des AgNWs sur la modification de la cinétique de réticulation du système, sa structure physique et sa mobilité moléculaire. La mesure des niveaux de conductivité volumique et surfacique du revêtement met en avant un seuil de percolation électrique pour un taux volumique en AgNWs inférieur à 1%. Une approche originale permettant la détermination des mécanismes de conduction a été effectuée au moyen des mesures de densités de courant imposées dans le revêtement en fonction du taux de charge en AgNWs et de la température. L'analyse du comportement électrique des échantillons aux valeurs critiques de densités de courant a permis d'appréhender les phénomènes responsables des mécanismes de dégradation. Enfin des essais foudres ont été effectués sur des substrats représentatifs d'une structure aéronautique avec différents types de protection foudre. L'analyse des échantillons par ultrasons après essais foudres a mis en avant l'efficacité du revêtement composite polymère conducteur poly(époxy)/AgNWs développé pour lutter contre le délaminage structurel du CFRP. / This work deals with the processing and the study of an extrinsic conductive polymer coating for the lightning strike protection of the aircraft carbon fibre reinforced polymer (CFRP) structural parts. The coating consist in a low viscosity bi component high performance poly(epoxy) matrix and silver submicronic wires with a high aspect ratio (AgNWs) obtained by a polyol process. The kinetic parameters, the physical structure and the molecular mobility of the matrix had been investigated as a function of the filler content. The surface and bulk conductivities had been measured as a function of filler content. It exhibits a percolation threshold below 1% in volume. The conduction mechanisms had been studied following an uncommon method of current density measurement as a function of the AgNWs content and the temperature. The critical electrical behaviour of each sample had been investigated through the current density method. It has permitted to understand the phenomenon responsible for the composite's degradation. Finally, lightning strike tests on representative configurations had been carried out. The ultrasonic inspections have highlighted the efficiency of the poly(epoxy)/AgNWs coating to avoid the structural delamination of the CFRP.

Thesis (Ph. D.)--State University of New York at Binghamton, Anthropology, 2006. / Includes bibliographical references.

Thesis (Ph. D.)--Dept. of Geosciences and School of Computing and Engineering. University of Missouri--Kansas City, 2005. / "A dissertation in geosciences and computer networking." Advisor: Tina M. Niemi. Typescript. Vita. Description based on contents viewed Mar. 12, 2007; title from "catalog record" of the print edition. Includes bibliographical references (leaves 331-341). Online version of the print edition.

Chaque année, d'innombrables collisions se produisent entre des avions en vol et des oiseaux. L'impact aviaire, menace redoutée par les pilotes, concerne tant l'aviation civile que son pendant militaire. Les statistiques démontrent que, même si fort heureusement le nombre d'accidents graves reste limité, les incidents sont de plus en plus nombreux. Parmi les acteurs qui luttent contre ce danger, les constructeurs d'avions jouent un rôle prépondérant. Contraints par des réglementations internationales, ils s'attachent à produire des éléments de structure qui résistent à l'impact d'oiseaux. Dans la mise au point de leur produits, les avionneurs démontrent cette résistance à l'aide d'essais d'impact : on accélère un simulant d'oiseau jusqu'à la vitesse voulue -- de l'ordre de la vitesse de croisière nominale de l'avion -- et on le projette sur un aileron ou un morceau de fuselage. La présente thèse doctorale, co-dirigée par les professeurs Philippe Bouillard de l'ULB et Marc Pirlot de l'ERM, contribue doublement à l'amélioration de ces techniques d'essais dynamiques. D'une part, elle réalise la mise au point et la validation d'un lanceur pyrotechnique à double étage pour l'accélération du simulant d'oiseau. Un canon de calibre 20 mm est combiné avec un accélérateur de calibre 160 mm. La combustion d'un mélange de poudre propulsive contenu dans une douille adaptée génère les gaz à haute température et à haute pression nécessaires à l'accélération d'un simulant d'oiseau dûment confiné dans un conteneur de protection. Un dispositif de séparation arrête le conteneur afin que seul le simulant d'oiseau percute l'élément d'avion à l'essai. La solution pyrotechnique à double étage mise au point est validée par de nombreux tirs instrumentés en vitesse, en accélération et en pression ; elle se révèle conforme aux exigences de sécurité et de reproductibilité. Le lanceur pyrotechnique présente par rapport aux solutions pneumatiques, utilisées à notre connaissance dans tous les autres centres d'essais, des avantages indéniables de compacité ainsi que de rapidité et de souplesse de mise en oeuvre. D'autre part, la migration des alliages métalliques vers les matériaux composites est amorcée depuis plusieurs années déjà dans le monde de la construction aéronautique. Pour optimiser les structures, une connaissance des caractéristiques de ces matériaux est indispensable. Les modes de rupture font partie des caractéristiques encore mal connues. La mesure du déplacement hors-plan lors du tir sur panneaux plans est une des manières de quantifier le comportement du matériau sous l'action d'un impact. Cette mesure s'opère généralement de manière statique, après le tir. Une méthode de mesure dynamique a été mise au point, basée sur l'emploi de techniques de stéréoscopie par corrélation numérique d'images. Cette technique a été validée au moyen d'une méthode métrologique indépendante d'extensométrie laser. ABSTRACT Countless collisions occur each year between airplanes and birds. Bird strike is a concern to both civilian and militay aircraft. Statistics show that, although the number of serious accidents fortunately remains low, the number of incidents keeps increasing. Amongst the actors tackling this issue, aircraft manufacturers play an important role. In compliance with international regulations, they have to produce structural elements that withstand bird impact. During the development of their products, aircraft manufacturers have to demonstrate this resistance through bird impact trials : a bird surrogate is accelerated to the required velocity - often close to the nominal cruise speed of the aircraft - and launched onto a flap or a piece of fuselage. This PhD thesis has been co-supervised by Professor Philippe Bouillard (ULB) and Professor Marc Pirlot (ERM-KMS). Its contribution to the improvement of the aforementioned dynamic trials is twofold. One one hand, a two-stage pyrotechnical launcher for bird surrogates has been developed and assessed. A 20 mm caliber gun is connected to a 160 mm diameter launcher. The combustion of a propellant mixture in a cartridge case generates high pressure, high temperature gases which accelerate a bird surrogate protected by a cylindrical container. A stripper refrains the container from hitting the target pane. The pyrotechnical solution has been assessed through an important number of firings where pressure, velocity and acceleration have been measured. The solution has proven compliance with both the safety requirements and the repeatability specifications. Its advantages compared to the pneumatic solutions used, as far as we know, in all other test centres, include compactedness as well as flexibility and high firing rate. On the other hand, migration towards composite materials has been initiated years ago in the area of aeronautical constructions. To optimize structures, a thorough knowledge of these new materials is required. Failure modes belong to the still badly known features of carbon reinforced plastics. Measuring the out-of-plane deformation when firing on a flat pane is one way of quantifying the material's behaviour under impact. This measurement is most frequently made in a static way, after completion of the firing. A dynamic measuring method has been developed, based upon stereoscopic digital image correlation techniques. This technique has been validated by means of an independent laser extensometer measuring method.

Drawing from oral histories which I gathered while living in Bolivia, this thesis tracks the start, growth, and development of the political movement led by women from the Bolivian mines from 1961 to 1987. This movement helped create a new political culture that recognized the importance of women’s participation in politics and human rights. Today, this culture lives on. Bolivia has not experienced a coup since 1980, and the nation’s human rights record has improved dramatically since the 1980s as well. Prior to the mid-1980s, Bolivia was often under the control of oppressive military regimes that resorted to many different types of coercion in attempts to silence resistance in the mining centers, the national government’s main source of conflict. This uneven power struggle between working class activists and the national government motivated many women to challenge gender roles and involve themselves in politics. After establishing their political organization called the Housewives’ Committee, women activists organized and acted collectively to challenge political oppression and mitigate the effects of extreme poverty. They frequently employed compelling tactics, most commonly hunger strikes, to win attention for their issues. They also involved themselves in many other diverse projects and demonstrations depending on their communities’ need. Women’s political development resulted in a number of personal transformations among those who participated: it awakened a political consciousness and also enabled women to recognize the importance of their paid and unpaid work in the mining economy. These changes eventually altered women’s understanding of how women’s oppression fit into the broader struggle of working class activism by convincing them of the deep connection between women’s liberation and the liberation of their community. These transformations led to the acceptance of women as political activists and leaders, which continues in the present. This work also tracks the United States’ impact on the relationship between the mining centers and the state. This analysis serves to remind us that as United States citizens we must be very critical of our nation’s impact; because of our ability to enormously affect small land-locked countries like Bolivia, we must also hold ourselves accountable to understanding our historical impact so that we can make informed decisions in the present.