Title: Memories of whithesses from the east of the Giant mountains Objectives: The aim of the work is to summarize historical events and social changes connected with the era from the beginning of colonization of the east of the Giant mountains to the second half of 1940s through utterance of regional natives compared to thematic literature. Methods: To gain data for this thesis regarding utterance of contemporary witnesses I used largely publications Krkonošští rodáci vzpomínají 1, 2 a 3, further a magazine Krkonoše-Jizerské hory, a website Paměť národa - Sudetské osudy (Antikomplex) and a method of semi- structured interview with one witness. I focused especially on German- speaking natives born in 1920s and 1930s from the east of the Giant mountains, largely from villages Horní Maršov and Velká Úpa and surroundings, occasionally supplemented by compatriots from the middle of the Giant mountains. It was 17 withesses in total - 8 women and 9 men. Afterwards I made a comparation of sources mentioned above with prefessional literature and populary educational literature and websites, which have a relation to the region and to period, historical and social events. Conclusion: The thesis introduced key moments of life stories of predominantly German-speaking withesses from the east of the Giant...

Que ce soit dans le domaine médical ou en contrôle non destructif, les systèmes d’imagerie ultrasonore sont devenus de plus en plus utilisés de nos jours. Leurs applications ne cessent de s’élargir et des performances toujours plus accrues sont vivement recherchées, afin d’améliorer la qualité des diagnostics réalisés. Nous sommes donc passés de l’utilisation de systèmes à base de transducteurs ultrasonores mono-élément à des systèmes utilisant des réseaux de transducteurs à une dimension (1D) et à deux dimensions (2D) composés d’éléments de plus en plus nombreux et petits. Néanmoins, un phénomène indésirable est fortement présent dans ces réseaux de transducteurs ultrasonores : il s’agit du couplage inter-éléments tendant à limiter leurs performances acoustiques et à modifier leur diagramme de rayonnement. Tout au long de ce travail de recherche, nous avons donc cherché à comprendre ce phénomène parasite et à apporter des solutions pour le réduire voire le supprimer. En se basant sur des modélisations éléments finis 2D et 3D et grâce à la fabrication de prototypes, nous avons d’une part, mis en évidence les différents types de couplages présents dans un réseau de transducteurs (acoustique, mécanique) et d’autre part, deux méthodes de correction basées l’une comme l’autre sur l’application de tensions convenables aux différents éléments du réseau ont été testées. La première méthode utilise les déplacements normaux moyens à la surface de chaque élément du réseau pour évaluer ces tensions, tandis que la deuxième fait appel aux courants motionnels parcourant chaque élément pour les déterminer. Les résultats numériques et expérimentaux concernant les déplacements et les diagrammes de rayonnement sont en bon accord. En outre, les deux méthodes s’avèrent particulièrement efficaces pour réduire le couplage inter-éléments. / Whether in medicine or in non-destructive testing, ultrasonic imaging systems have become increasingly used nowadays. Their applications continue to expand and good performances are needed to improve the quality of the diagnosis. Moreover, significant progress has been made since these systems were originally based on single element ultrasonic transducers and are now made of mono-dimensional (1D) and bi-dimensional (2D) elements arrays ever more numerous and smaller. However, an undesirable phenomenon is strongly present in the ultrasonic transducer arrays: it is the cross-talk, which limits their acoustic performances and modifies their radiation pattern. Throughout this research, we have attempted on one hand to understand this parasitic phenomenon and on the other hand to provide solutions in order to reduce it or even remove it. To highlight the cross-talk types (acoustic and mechanical) and to test the proposed correction methods, we developed two-dimensional (2D) and three-dimensional (3D) finite element modeling and fabricated some prototypes. Both correction methods rely on the application of suitable voltages to the array elements. The first method uses the average of the normal displacements at the surface of each element to evaluate the voltages, while the second one utilizes the motional currents through each element to determine them. The numerical and experimental results concerning the displacements and the radiation patterns are in good agreement. In addition to this, both methods have been efficiently performed to reduce the cross-talk.

Successful wind power projects start with a realistic representation of the surface, more specifically the surface roughness of the site. This thesis investigates the use of airborne laser scans to model the surface roughness around a new wind farm. Estimations are made to find out how forest management and tree growth affects roughness length and displacement height. Data from scans two years apart for a specific site is provided by the Swedish governmental land registration authority. Next, tree height and plant area index methods are applied and analyzed using MATLAB. The results shows a difference of roughness length between 10.34% and 36.21% during an eight year period. WindPRO/WAsP is used to import roughness lengths for four specific cases. Height contour lines and meteorological data is taken from a long term corrected MESO data set. The results indicate a reduction in uncertainty in annual energy production between 0.79% and 2.89% across four different cases. This effect becomes significantly larger (12.76%) when comparing with classical land cover maps. Further on, effects of turbulence intensity are simulated.Finally, the results of a survey, sent to three large forest land owners in Sweden, show there is an interest in adapting forest management plans in favor of wind energy production if benefits can be shared.

O presente trabalho aborda as deformações por encurtamento dos pilares durante a fase construtiva. Deformações, estas, devidas à progressão das cargas, devidas à fluência e devidas à retração. Os encurtamentos provocam deslocamentos que são parcialmente corrigidos pelo processo construtivo, seja a obra executada com os pavimentos no nível de projeto ou com o piso-a-piso fixo. Dessa forma, o deslocamento final é inferior àquele obtido por um modelo de passo único que considera todas as ações ocorrendo após a finalização da estrutura. Uma metodologia para a estimativa dos encurtamentos e das correções é proposta e os resultados obtidos a partir dessa metodologia são validados por meio de comparações com modelos computacionais. Além disso, um carregamento fictício de temperatura é proposto para simular as correções construtivas no modelo de passo único. A variação de temperatura mostrou-se simples, precisa e útil nas análises de edificações de múltiplos pavimentos. Por fim, são discutidos os possíveis danos em elementos não-estruturais e maneiras de se mitigar esse problema. / The present study adress the issue of column shortening during the construction. These deformations are due to the progression of loads, due to creep and due to shrinkage. Shortenings cause displacements, that are partially compensated by the construction process, either the construction is performed with the floors executed at the design level, or the construction executed with fixed floor-to-floor dimension. Thus, the final displacement is lower than the displacement obtained by a single-step model, that considers all actions taking place after the structure is finished. A methodology for the estimation of shortenings and corrections is proposed and the results obtained from this methodology are validated through comparisons with computational models. In addition, a fictitious temperature load is proposed to simulate the constructive corrections in the single-step model. The temperature variation proved to be simple, accurate and useful in the analysis of multi-storey buildings. Finally, the possible damages in non-structural elements and ways to mitigate this problem are discussed.

Artificial Neural Networks (ANNs) can be viewed as a mathematical model to simulate natural and biological systems on the basis of mimicking the information processing methods in the human brain. The capability of current ANNs only focuses on approximating arbitrary deterministic input-output mappings. However, these ANNs do not adequately represent the variability which is observed in the systems’ natural settings as well as capture the complexity of the whole system behaviour. This thesis addresses the development of a new class of neural networks called Stochastic Neural Networks (SNNs) in order to simulate internal stochastic properties of systems. Developing a suitable mathematical model for SNNs is based on canonical representation of stochastic processes or systems by means of Karhunen-Loève Theorem. Some successful real examples, such as analysis of full displacement field of wood in compression, confirm the validity of the proposed neural networks. Furthermore, analysis of internal workings of SNNs provides an in-depth view on the operation of SNNs that help to gain a better understanding of the simulation of stochastic processes by SNNs.

The application of static shape control was investigated in this thesis particularly for a composite plate configuration using piezoelectric actuators. A new electro-mechanically coupled mathematical model was developed for the analysis and is based on a third order displacement field coupled with a layerwise electric potential concept. This formulation, TODL, is then implemented into a finite element program. The mathematical model represents an improvement over existing formulations used to model intelligent structures using piezoelectric materials as actuators and sensors. The reason is TODL does not only account for the electro-mechanical coupling within the adaptive material, it also accounts for the full structural coupling in the entire structure due to the piezoelectric material being attached to the host structure. The other significant improvement of TODL is that it is applicable to structures which are relatively thick whereas existing models are based on thin beam / plate theories. Consequently, transverse shearing effects are automatically accounted for in TODL and unlike first order shear deformation theories, shear correction factors are not required. The second major section of this thesis uses the TODL formulation in static shape control. Shape control is defined here as the determination of shape control parameters, including actuation voltage and actuator orientation configuration, such that the structure that is activated using these parameters will conform as close as possible to the desired shape. Several shape control strategies and consequently algorithms were developed here. Initial investigations in shape control has revealed many interesting issues which have been used in later investigations to improve shape controllability and also led to the development of improved algorithms. For instance, the use of discrete actuator patches has led to greater shape controllability and the use of slopes and curvatures as additional control criteria have resulted in significant reduction in internal stresses. The significance of optimizing actuator orientation and its relation to piezoelectric anisotropy in improving shape controllability has also been presented. Thus the major facets of shape control has been brought together and the algorithms developed here represent a comprehensive strategy to perform static shape control.

This work concerns the simulation of viscoelastic behavior of polymer at different states. Viscoelastic modeling of polymer was performed from the solid state to the liquid state via a multiphase approach which is largely used to deal with the fluid structure interaction. To ensure the appreciation of the FSI, viscoelasticity is considered in two parts: an elastic one and viscous other where the main idea is to use a mixed formulation in three fields (u, v, p) (displacement, velocity, pressure), with u and v, represented the primary variables of a strain and a strain rate formulation. We are led to the Navier-Stokes compressible problem with extra-stress, which is solved by using the Mixed Finite Element. The present work contributes some stabilization elements to the numerical simulation of multiphase problem by the monolithic approach.Comparison between the literature and experiments was performed through the validation of an elastic case and the viscoelastic Kelvin-Voigt model in the context of Lagrangian framework as well as Eulerian framework. The extension of the methodology to a visco-hyper-elastic is given through the modeling and validation on material point on the finite elements library CimLib®. Finally, a stabilization scheme of the EVSS type is adopted for viscoelastic Kelvin-Voigt model, hyper-elastic Neo-Hookean model, and also visco-hyper-elastic model which proposed an open door in computational modeling, not only with viscoelasticity but also complex dynamic application.

There are many options available when selecting a computational model for two-phase flows. It is important to understand all the features of the model selected, including when the model is appropriate and how using it may affect your results. This work examines how volume displacement effects in two-phase Eulerian-Lagrangian models manifest themselves. Some test cases are examined to determine what input these effects have on the flow, and if we can predict when they will become important. Bubble injection into a traveling vortex ring is studied in-depth, as it provides significant insight into the physics of these volume displacement effects. When a few bubbles are entrained into a traveling vortex ring, it has been shown that even at extremely low volume loadings, their presence can significantly affect the structure of the vortex core (Sridhar & Katz 1999). A typical Eulerian-Lagrangian point-particle model with two-way coupling for this dilute system, wherein the bubbles are assumed subgrid and momentum point-sources are used to model their effect on the flow, is shown to be unable to accurately capture the experimental trends of bubble settling location, bubble escape, and vortex distortion for a range of bubble parameters and vortex strengths. Accounting for fluid volume displacement due to bubble motion, using a model termed as volumetric coupling, experimental trends on vortex distortion and bubble settling location are well captured. The fluid displacement effects are studied by introducing the notion of a volume displacement force, the net force on the fluid due to volumetric coupling, which is found to be dominant even at the low volume loadings investigated here. A method of quantifying of these forces is derived and used to study the effects for a wide range of particle to fluid density ratios in Taylor-Green vortices. A simple modification to the standard point-particle Lagrangian approach is developed, wherein the interphase reaction source terms are consistently altered to account for the fluid displacement effects and reactions due to bubble accelerations. / Graduation date: 2013 / Access restricted to the OSU Community at author's request from Sept. 24, 2012 - Sept. 24, 2013

There is a tendency in archaeology dealing with watercraft landing sites in a wider context to assume a direct relationship between sites in coastal and shore-bound areas and the practise of landing, without any deeper practical or theoretical exploration of the reality of any such relationship. This problem has its origins in the poor archaeological and conceptual definitions of watercraft landing sites obstructing any real understanding of the role of these sites in the maritime cultural landscape. Landing sites are taken for granted and they are undervalued as an archaeological source of explanation; notwithstanding, the concept of the landing site is readily used in archaeology in order to underpin archaeological interpretations on the maritime activities of past societies. In order to break away from the simplified understandings of past water-bound strategies based on the undefined concept of the landing site, this dissertation suggests a definition of watercraft landing sites in a wider social sense as water-bound contact zones; places of social interaction that can be archaeologically identified and investigated. This perspective integrates the understanding of the intentional character of human activity related to watercraft landing with the remaining archaeological traces. Archaeological definitions of landing sites that can be tested against the archaeological data are provided, and thereby, the dissertation contributes with the possibility to archaeologically evaluate and approach the social function of watercraft landing sites. This dissertation demonstrates that there can be an archaeology of landing sites.

Taking the establishment of Ice Age theory as its point of departure, the present dissertation examines aspects of geological, plant geographical and archaeological research on shoreline displacement conducted in Sweden during the period 1860-1930, and the significance of this research for the perception of "the Swedish landscape" and its post-glacial history. The research is analyzed on three levels under the rubrics "The Highest Shoreline and the Ancylus Lake", "The Question of Land Elevation", and "Charting Swedens Past", respectively. Taken together, these levels capture the varying perceptions and exchanges of opinion of the nature of shoreline displacement and the contexts in which they were applied. The present study is conducted via a theoretical and methodological approach where both the ideas and the practices of science are studied: activities in the field and at the various institutions (primarily the Swedish Geological Survey, its museum and the Geological Society of Stockholm); arguments and hypotheses presented in artides and handbooks, including visual images, diagrams and maps; social networks, career paths and controversies. Particular attention is paid to the relationship between science and nationalism, and comparisons are made with research conducted in an imperialist context. Ice Age theory helped initiate research whose purpose was to discover how the Swedish naturai and cultural landscape carne into being. The foremost task of geology became studying geographic evolution during the Quaternary epoch, how the land had "risen from ice and water". Plant geography studied how and whence plant life had migrated and how vegetation had evolved under the influence of biological, geological and climatological factors. In a similar manner, archaeologists studied the migration and dissemination of mankind during the StoneAge. When natural scientists primarily used "natural landmarks" as its source material, archaeologists relied on "archaeological finds", which were invested with scientific value but also became symbols of national collective memory. Through this survey, national identity was unifìed with the territory itself and its evolutionary history. Knowledge about shoreline displacement became significant for geology, plant geography and archaeology, which in turn encouraged interdisciplinary collaboration, but also locked the researchers into a similar way of thinking about the nature of shoreline displacement. According to this "thought style", the phenomenon was first and foremost the result of the vertical movement of the land rather than movement in the ocean surface. Up until the 1870s, the Ice Age was thought to have been followed by one single subsidence and elevation; during the 1880s, two such land oscillations; three during the 1910s and by the 1920s, five. Only toward the end of the 1920s did Swedish researchers begin to accept a multi-factor explanation, which succeeded in finally subverting the reigning thought style. According to this explanation, shoreline displacement was not solely the result of changes in the land or the sea, but of both. / digitalisering@umu