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Space satellite technology is heading in the direction of ultra-large, lightweight structures deployable on orbit. Minimal structural mass translates into minimal launch costs, while increased satellite bus size translates into significant bandwidth improvement for both radar and optical applications. However, from a structural standpoint, these two goals are in direct conflict with one another, as large, flexible structures possess terrible dynamic properties and minimal effective bandwidth. Since the next level of research will require active dynamic analysis, vibration control, and shape morphing control of these satellites, a better-suited name for this technology is Super Precise Intelligent Deployables for Engineered Reconnaissance, or SPIDER. Unlike wisps of cobweb caught in the wind, SPIDER technology will dictate the functionality and versatility of the satellite much like an arachnid weaving its own web. In the present work, a rigorous mathematical framework based on distributed parameter system theory is presented in describing the dynamics of augmented membranous structures. In particular, Euler-Bernoulli beam theory and thin plate theory are used to describe the integration of piezoelectric material with membranes. In both the one and two dimensional problems, experimental validation is provided to support the developed models. Next, the linear quadratic regulator (LQR) control problem is defined from a distributed parameter systems approach, and from this formulation, the functional gains of the respective system are gleaned. The functional gains provide an intelligent mapping when designing an observer-based control system as they pinpoint important sensory information (both type and spatial location) within the structure. Further, an experimental investigation into the dynamics of membranes stretched over shallow, air-filled cavities is presented. The presence of the air-filled cavity in close proximity to the membrane creates a distributed spring and damping effect, thus creating desirable system dynamics from an optical or radar application perspective. Finally, in conjunction with the use of a pressurized cavity with a membrane optic, a novel basis is presented for describing incoming wavefront aberrations. The new basis, coined the clamped Zernike polynomials, provides a mapping for distributed spatial actuation of a membrane mirror that is amiable to the clamped boundary conditions of the mechanical lens. Consequently, based on the work presented here and being carried out in cooperation with the Air Force Research Laboratory Directed Energy Directorate (AFRL / DE), it is envisioned that a 1 m adaptive membrane optic is on the verge of becoming a reality. / Ph. D.

In this report we attempt to provide insights in how interpolation can be used for creating heat maps showing residence prices for different residence markets in Sweden. More specifically, three interpolation methods are implemented and are then used on three Swedish residence markets. These three residence markets are of varying characteristics such as size and residence type. Data of residence sales and the physical definitions of the residence markets were collected. As residence sales are never identical, residence sales were preprocessed to make them comparable. For comparison, a so-called external predictor was used as an extra parameter for the interpolation method. In this report, distance to nearest public transportation was used as an external predictor. The interpolated heat maps were compared and evaluated using both quantitative and qualitative approaches. Results show that each interpolation method has its own strengths and weaknesses, and that using an external predictor results in better heat maps compared to only using residence price as predictor. Kriging was found to be the most robust method and consistently resulted in the best interpolated heat maps for all residence markets. On the other hand, it was also the most time-consuming interpolation method. / Den här rapporten försöker ge insikter i hur interpolation kan användas för att skapa färgdiagram över bostadspriser för olika bostadsmarknader i Sverige. Mer specifikt implementeras tre interpolationsmetoder som sedan används på tre olika svenska bostadsmarknader. Dessa tre bostadsmarknader är av olika karaktär med hänsyn till storlek och bostadstyp. Bostadsförsäljningsdata och de fysiska definitionerna för bostadsmarknaderna samlades in. Eftersom bostadsförsäljningar aldrig är identiska, behandlas de först i syfte att göra dem jämförbara. En extern indikator, vilket är en extra parameter för interpolationsmetoder, undersöktes även. I den här rapporten användes avståndet till närmaste kollektiva transportmedel som extern indikator. De interpolerade färgdiagrammen jämfördes och utvärderades både med en kvantiativ och en kvalitativ metod. Resultaten visar att varje interpolationsmetod har sina styrkor och svagheter och att användandet av en extern indikator alltid renderade i ett bättre färgdiagram jämfört med att endast använda bostadspris som indikator. Kriging bedöms vara den mest robusta interpolationsmetoden och interpolerade även de bästa färgdiagrammen för alla bostadsmarknader. Samtidigt var det även den mest tidskrävande interpolationsmetoden.

[pt] Escoamentos aerodinâmicos externos sobre membranas e aerofólios finos representam um enorme desafio para simulações numéricas, tendo em vista os diversos e complexos regimes de escoamento presentes, que incluem separa ção da camada limite, transição da camada de mistura para regime turbulento, recolamento, relaminarização da camada limite, e formação de bolhas de recirculação primárias e secundárias. Uma maior compreensão sobre estas estruturas é obtida através da simulação numérica de grandes escalas (LES) do escoamento sobre placas planas e finas, com ângulos de incidência entre um e três graus e número de Reynolds superior a 105. A necessidade do emprego de malhas não uniformes, geralmente imposta por escoamentos externos, provoca instabilidades numéricas em esquemas não dissipativos, sendo duas possíveis soluções apresentadas nesse trabalho. A primeira delas é baseada num modelo sub-malha tradicional, onde a estabilidade numérica é alcançada através de um esquema numérico misto, no qual o esquema de diferenças centrais é empregado em regiões com intensas atividades turbulentas, enquanto que um esquema dissipativo é empregado nas regiões onde a malha sofre grandes variações espaciais e a atividade turbulenta é desprezível. Uma segunda solução baseia-se num termo de forçamento idealizado para atenuar apenas as menores escalas. Quando comparadas a estudos prévios utilizando médias de Reynolds (RANS), ambas as alternativas se mostraram adequadas, disponibilizando resultados bem mais precisos para perfis de velocidade, flutuações turbulentas e pressões médias. Em particular, o comprimento da bolha de recirculação foi previsto com menos de 5% de discrepância em relação a dados experimentais, contrastando com valores maiores que 20%, obtidos com o modelo RANS K - W / [en] Aerodynamic flows around thin airfoils and membranes are very challenging to simulate accurately because of complex flow structures, including geometry-induced separation of the boundary layer, shear layer transition to turbulent behavior, reattachment, relaminarization of the boundary layer, and formation of primary and secondary recirculation bubbles. A physical insight on these structures can be obtained through the numerical Large Eddy Simulation (LES) of the flow around a simpler geometry, the thin flat plate, at shallow incidences of one and three degrees and Reynolds number above 105, which is the focus of this investigation. In order to avoid the numerical instabilities associated with the mesh spreading generally required by such external flow, two solutions have been developed and tested. The first one consists of the traditional sub-grid model used along with a mixed numerical scheme, in which a stable but dissipative part is active only in turbulence-free zones where mesh is highly non-regular, while an unstable but non-dissipative scheme is employed in turbulence- crytical zones, where the mesh is as regular as possible. The second solution, developed and validated in the current investigation, is based on a damping force, aimed to eliminate the smaller scales while preserving as much as possible all other structures. Compared to previous investigations using Reynolds Average (RANS) equations, both solutions provided more accurate and detailed information about the flow, including velocity, pressure and turbulent fluctuations mean profiles, allowing a deeper physical understanding. In particular, the main bubble reattachement lenght was predicted within 5% of the experimental data, while K - W RANS results were found to disagree in more than 20%.

Lors de l'assemblage de wafers par adhésion moléculaire, un mince film d'air est piégé entre les deux wafers, créant ainsi un système fluide/structure couplé.La qualité finale de l'assemblage dépend fortement de la dynamique de ce système.L'initiation et la propagation du collage ont été étudiées, en régime transitoire, en utilisant un modèle de plaques minces couplée avec l'équation de Reynolds. La résolution numérique de l'équation, ainsi que la mesure optique du déplacement vertical de la plaquette durant le collage, nous a permis de valider le modèle et de mieux comprendre la dynamique du collage.Dans la continuité de cette étude, nous avons proposé une expression analytique de la courbure finale de l'assemblage en fonction des forces en jeu pendant le collage, ceci en utilisant à nouveau la théorie des plaques minces et en considérant l'exitence d'un saut de déformation transverse le long de l'interface collée.Ce modèle a été validé par une expérience, impliquant le collage de wafers d'épaisseur différentes et en prenant soin de contrôler l'ensemble des forces agissant sur ces wafers. Nous observons une influence importante du film d'air sur la forme finale des wafers.En complément, un modèle du travail d'adhésion a été développé prenant en compte, à la fois, la rugosité d'interface et la quantité d'eau adsorbée. La différence de répartition de l'eau à l'interface de collage, nous permet d'expliquer les résultats expérimentaux montrant des valeurs d'énergie de séparation supérieure à celle de l'adhésion.Enfin, nous proposons une nouvelle méthode de mesure du travail d'adhésion pour la géométrie entière des wafers, utilisant la mesure de la taille d'une bulle cylindrique intentionnellement créée, par un petit objet, à l'interface de collage. / The direct wafer bonding process involves a coupled physical system, formed by the elastic deformation of the wafers and a thin layer of fluid trapped in-between the two wafers.Dynamics of the system during the contacting step has many practical consequences on the quality of the assembled stack.A model for the bonding dynamics is formulated using the thin plate theory and the Reynolds equation. The transient equation is solved numerically, allowing to study both the initiation and the propagation of the bonding. The model is supported by the measurement of the vertical movement of the wafer during the bonding, using an original setup involving optical sensors.Subsequently, an analytical model for the final curvature of the bonded stack is derived, as a function of the different load components acting on the wafers during the bonding, using the thin plate theory and by considering a transverse strain discontinuity locked at the bonding interface.Experimental validation is performing using two different wafer thicknesses. The measured bonded wafer profiles are well described by the model.In addition, a model for the work of adhesion is developed, taking into account both the interface roughness and the amount of adsorbed water.The interface energy controlling the adhesion is found different than for the separation because of the different distribution of water along the interface, in agreement with the experimental observations. At last, a new method to accurately measure the work of adhesion for the entire wafers geometry is proposed, using an elongated bubble intentionally created at the bonding interface and by measuring the induced wafer deflection.

The aim of this study is to present a novel three dimensional (3D) facial animation method for morphing emotions and facial expressions from one face model to another. For this purpose, smooth and realistic face models were animated with thin plate splines (TPS). Neutral face models were animated and compared with the actual expressive face models. Neutral and expressive face models were obtained from subjects via a 3D face scanner. The face models were preprocessed for pose and size normalization. Then muscle and wrinkle control points were located to the source face with neutral expression according to the human anatomy. Facial Action Coding System (FACS) was used to determine the control points and the face regions in the underlying model. The final positions of the control points after a facial expression were received from the expressive scan data of the source face. Afterwards control points were transferred to the target face using the facial landmarks and TPS as the morphing function. Finally, the neutral target face was animated with control points by TPS. In order to visualize the method, face scans with expressions composed of a selected subset of action units found in Bosphorus Database were used. Five lower-face and three-upper face action units are simulated during this study. For experimental results, the facial expressions were created on the 3D neutral face scan data of a human subject and the synthetic faces were compared to the subject&rsquo / s actual 3D scan data with the same facial expressions taken from the dataset.

In the presented paper the changes in mean runoff, temperature and precipitation totals in an observed period 1962-2015 in the catchment river Hačka are assessed. The paper further presents the analysis of climate change impact on mean runoff between the periods 1984-2014 (control period) and 2035-2065 and 2068-2098 (scenario periods) using the projections of three regional climate model simulations. Thin Plate Spline interpolation was used to estimate basin precipitation and temperature. Modified hydrological analogy was used for precise quantification of naturalized runoff (i.e. not affected by water use). Climate change scenarios were derived using simple delta change approach, i.e. observed series of precipitation and temperature were adjusted in order to give the same changes between the control and scenario period as regional climate model simulations. Hydrological balance was modelled with a conceptual hydrological model Bilan. The parameters of the hydrological model were estimated using observed data. These parameters were subsequently used to derive discharge series under climate change conditions for each regional climate model simulation. Results showed a 1.7 °C average increase in mean annual temperature in the scenario period 2035-2065 and a 2.8 °C average increase in the scenario period 2068-2098. The seasonal cycle of precipitation in the scenario conditions is shifted, although mean annual precipitation totals remain practically unchanged (max changes -8.1 %; +9.3 %). The mean annual discharge decreases by 5.7% in average (most 20.3 %) in period 2035-2065 and a significant decrease of 25.5% in average (most 45.9 %) in annual mean discharge is expected in the period 2068-2098. Frequency of minimal runoff is expected to increase up to two times. Precipitation increase is expected from the beginning of the fall to the beginning of the summer, with a slight decrease in spring. Increase in precipitation is followed by evapotranspiration increase, caused by increase in temperature. Summer precipitation is expected to decrease as well as summer runoff. Due to the temperature increase, time shift of the snowmelt is expected from the periods between March-April to January-February. This will also affect the increase of the discharge in this period. This knowledge can be applied in water management planning in the future.

This study deals with morphological variation in the Melampyrum sylvaticum group (Orobanchaceae). Populations of the Hercynian Massif, Western and Eastern Carpathians were investigated using both conventional and geometric morphometric methods. Individual morphological characters were evaluated in detail. Preliminary taxonomic concept of the group is presented. Biogeographical context of detected morphological variation is discussed.

This diploma thesis is concerned to determination of countercurrent proces of water surface level decrease before the thin-plate rectengular-notch weir. The measuring of the depth of water is to determine properly the flow standard. For this reason is the experimental measurements the main topic of this thesis. The aim was to do some measuring on free thin-plate- rectangular with weir b=250 mm, b=200 mm and b=150 mm. The values were evaluated and attain results were compared with the results which were reported in the literature.

abstract: Stress-related failure such as cracking are an important photovoltaic (PV) reliability issue since it accounts for a high percentage of power losses in the midlife-failure and wear-out failure regimes. Cell cracking can only be correlated with module degradation when cracks are of detectable size and detrimental to the performance. Several techniques have been explored to access the deflection and stress status on solar cell, but they have disadvantages such as high surface sensitivity. This dissertation presents a new and non-destructive method for mapping the deflection on encapsulated solar cells using X-ray topography (XRT). This method is based on Bragg diffraction imaging, where only the areas that meet diffraction conditions will present contrast. By taking XRT images of the solar cell at various sample positions and applying an in-house developed algorithm framework, the cell‘s deflection map is obtained. Error analysis has demonstrated that the errors from the experiment and the data processing are below 4.4 and 3.3%. Von Karman plate theory has been applied to access the stress state of the solar cells. Under the assumptions that the samples experience pure bending and plain stress conditions, the principal stresses are obtained from the cell deflection data. Results from a statistical analysis using a Weibull distribution suggest that 0.1% of the data points can contribute to critical failure. Both the soldering and lamination processes put large amounts of stress on solar cells. Even though glass/glass packaging symmetry is preferred over glass/backsheet, the solar cells inside the glass/glass packaging experience significantly more stress. Through a series of in-situ four-point bending test, the assumptions behind Von Karman theory are validated for cases where the neutral plane is displaced by the tensile and compressive stresses. The deflection and stress mapping method is applied to two next generation PV concepts named Flex-circuit and PVMirror. The Flex-circuit module concept replaces traditional metal ribbons with Al foils for electrical contact and PVMirror concept utilizes a curved PV module design with a dichroic film for thermal storage and electrical output. The XRT framework proposed in this dissertation successfully characterized the impact of various novel interconnection and packaging solutions. / Dissertation/Thesis / Doctoral Dissertation Materials Science and Engineering 2019