Vacuum bags in conjunction with autoclaves are currently employed to generate the consolidation pressures and temperatures required to manufacture aerospace level composites. As the scale of continuous fiber composite structures increases autoclaving becomes prohibitively expensive or impossible. The objective of this work is to develop flexible magnetic clamping structures to increase the consolidation pressure in conventional vacuum bagging of composite laminates, thereby obviating the need for an autoclave. A ferromagnetic rubber, which consists of rubber filled with iron, is being developed as a conformable and reusable vacuum bag that provides increased consolidation through attractive forces produced by electromagnets. Experiments and finite element modeling indicate that consolidation pressure in the range of 100 kPa can be generated by such a device with realistic power requirements. The effects of the magnetic clamping device process parameters on the consolidation pressure magnitude are modeled and characterized. In addition, a method for the efficient design of the magnetic clamping device is developed.

By tracking the intersection of contemporary fiction and the information technologies of the digital age, this thesis argues that the narratives being produced over the past ten years have evolved into a distinct genre of literature, one where the aesthetics of fragmentation and postmodern uncertainty must confront the new realities of a digitally saturated culture and society. In order to demonstrate this alteration in contemporary fiction, this thesis considers novels written within the past ten years that reflect on this new form of textuality, namely Don DeLillo’s Cosmopolis (2003) and David Eggers’ The Circle (2013). These texts demonstrate a paradigm shift in contemporary literature, a new kind of fiction in which American society, culture, economics, and politics, are all directly affected by various forms of digital mediatisation. These authors reflect an altered cultural zeitgeist within their fiction—writings which can be differentiated from the postmodern literary aesthetic—prompted by neoteric digital technologies coupled with the ubiquitous nature of the Internet. Although this topic is broad and covers multiple fields of scholarly interests, my thesis nonetheless concerns itself with a very specific line of questioning: will our authors have the imaginative wherewithal and social sensitivity to keep pace with changes brought forth by the explosion of information technologies? If so, what type of fiction is likely to emerge from this new digital environment? By taking a focused approach and using contemporary literature as representative of these massive social, economic, and political transformations, my research recalls Kurt Vonnegut’s “Canary in the Coal Mine” dictum: the writer has always been the first to notice the dramatic effects of technology on the individual and the culture at large.

A di-2-piridil cetona benzoilhidrazona (DPKBH) é um reagente solúvel em uma série de solventes orgânicos mas pouco solúvel em água. Vem sendo utilizado para a determinação de metais, (principalmente do grupo de transição) como Fe(II), Fe(III), Ni(II), Cu(II), entre outros e como ligante de referência para estudar o comportamento dos íons Fe(II) e Fe(III) em presença de espécies orgânicos encontrados em águas naturais. Com o objetivo de entender melhor as propriedades do DPKBH em meio de etanol, foi necessário determinar as constantes de dissociaçãolionização em diferentes porcentagens desse solvente orgânico (10, 19, 29 e 48 %). Nestas porcentagens de etanol, através de medidas absolutas de pH determinaram-se os pKs do DPKBH utilizando-se a técnica potenciométrica e em 10 e 48 % de etanol através de medidas absolutas de pH associadas às absorbâncias das espécies presentes nos equilíbrios, utilizando-se a técnica espectrofotométrica. Nas devidas porcentagens de etanol, o comportamento do eletrodo foi previamente determinado. Os valores de pK1 3,210; 3,342; 3,398 e 3,360 e de pK2 10,834; 11,013; 11,793 e 11,382 foram obtidos respectivamente para 10, 19, 29 e 48 % de etanol, utilizando-se a técnica potenciométrica. Através da técnica espectrofotométrica os valores de pK1 foram 3,257 e 3,322 e pK2 10,880 e 11,820, em 10 e 48 % de etanol, respectivamente. / The di-2-pyridyl ketone benzoylhydrazone (DPKBH) is a soluble reagent in different organic solvents but slightly soluble in water. It has been used for metal determinations, (mainly transition metals) such as for Fe (II), Fe(III), Ni(II), Cu(II) and also like a reference ligand to study the behavior of Fe(II) and Fe(III) ions in the presence of organic species found in natural waters. So as to better understand the DPKBH properties In ethanol, it was necessary to determine the dissociation/ionization constant in different percentages of ethanol (l0, 19, 29 and 48%). In these ethanol percentages, through absolute pH measurements, pKs of DPKBH could be the found by using the potentiometric technique, and in 10 and 48% of ethanol the pKs of DPKBH were determined with pH measurements associated to absorbance of the species present in the equilibria by using the spectrophotometric technique. In appropiate percentage of ethanol the behavior of the glass electrode was previously determined. The pK1 values 3.210; 3.342; 3.398 and 3.362, and pK2 10.834; 11.013; 11.793 and 11.382 were found for 10,19,29,48 % of ethanol, by using the potentiometric technique. The spectrophotometric technique led to pK1 values 3.257 and 3.322, and the pK2 ones 10.880 and 11. 820 in 10 and 48 % of ethanol respectively.

The master thesis is focused on the simulation of the toroid coils in Ansoft Maxwell 3D software, which uses finite element method for electromagnetic field simulation. Firstly the process creation of the geometric model toroid coil with seventy-five threaded is presented. It is necessary to debug this model and prepare it for the mesh generation. Physical properties are assign to this model and it gives rise to the physical model. We will set boundaries, excitation current, core material, winding material and the parameters for the mesh generations. New material Kashke K4000 will be created in the materials library and subsequently we will define its BH curve on the basis of datasheet. Analysis is made in two modes. Direct currents (7,5A; 10A; 15A; 20A; 25A) and (non)linear materials are used in magnetostatic solution. Toroid coil is excited by current pulse in transient solution. In Ansoft Maxwell Circuit editor a source which generates current pulse will be created. This excitation will be assigned to the toroid coil as an extern source through a terminal. Core material is linear in the case of transient analysis, because Ansoft Maxwell 3D doesn´t allow to use nonlinear material in this solution. Settings are different in transient and in magnetostatic analysis. End time and time step are entered to solve this task in transient analysis. Time points are entered too. Flux density and electromagnetic field strength are calculated in these time points and later it will be possible to view the results. Calculated fields are shown as the pictures in this thesis. The procedure how to use a field calculator in the postprocessing is given as well. The achievements are summarized in the conclusion.

The thermally-driven rotating annulus is a laboratory experiment used to study the dynamics of planetary atmospheres under controlled and reproducible conditions. The predictability of this experiment is studied by applying the same principles used to predict the atmosphere. A forecasting system for the annulus is built using the analysis correction method for data assimilation and the breeding method for ensemble generation. The results show that a range of flow regimes with varying complexity can be accurately assimilated, predicted, and studied in this experiment. This framework is also intended to demonstrate a proof-of-concept: that the annulus could be used as a testbed for meteorological techniques under laboratory conditions. First, a regime diagram is created using numerical simulations in order to select points in parameter space to forecast, and a new chaotic flow regime is discovered within it. The two components of the framework are then used as standalone algorithms to measure predictability in the perfect model scenario and to demonstrate data assimilation. With a perfect model, regular flow regimes are found to be predictable until the end of the forecasts, and chaotic regimes are predictable over hundreds of seconds. There is a difference in the way predictability is lost between low-order chaotic regimes and high-order chaos. Analysis correction is shown to be accurate in both regular and chaotic regimes, with residual velocity errors about 3-8 times the observational error. Specific assimilation scenarios studied include information propagation from data-rich to data-poor areas, assimilation of vortex shedding observations, and assimilation over regime and rotation rate transitions. The full framework is used to predict regular and chaotic flow, verifying the forecasts against laboratory data. The steady wave forecasts perform well, and are predictable until the end of the available data. The amplitude and structural vacillation forecasts lose quality and skill by a combination of wave drift and wavenumber transition. Amplitude vacillation is predictable up to several hundred seconds ahead, and structural vacillation is predictable for a few hundred seconds.

This Creative Writing PhD consists of a novel, The Encyclopaedia of Istanbul, and accompanying critical essays, Ottoman Crossroads: Coffeehouses, Politics, Theatres and Storytelling. The Encyclopaedia of Istanbul is historical in nature, and magically real in temperament. It is an account of fin de siècle Constantinopolis, and contains forgotten fairy tales, remnants of an ancient manuscript culture, Armenian playwrights, Turkish feminists, Greek fortune-tellers and Sephardim cantors. It tells the tale of six intersecting lives in 1876, a time known as “the year of the three Sultans” in Ottoman history. This period was filled with tensions between traditionalism and Westernization, but also new political possibilities forwarded by the Young Ottomans. While the characters in The Encyclopaedia of Istanbul are fictitious, they are inspired by historical events and figures. The second element of my PhD, Ottoman Crossroads, is made up of four individual essays that focus on selected themes from the novel. They scrutinize, in order of presentation, the history of coffeehouse culture, the secretive society of the Young Ottomans and their political thought, the formation of Armenian-Turkish theatre, and the rediscovery of Ottoman fairy tales. Whilst the novel and essays are coherent independently, they also link to each other in ways that are sometimes direct, and at other times subtle.

This Thesis is devoted to theoretical investigation of the effective magnetic properties of nonlinear metamaterials, based on resonant conductive elements.A general expression for the effective bulk ermeability in the microwave frequency range is derived. Frequency dispersion of the permeability is studied and recommendations for optimisation of metamaterials with negative permeability are given. The results are supported with numerical simulation of the finite metamaterial sample.Next, a metamaterial possessing nonlinear magnetic responseowing to nonlinear electronic components, inserted into resonant conductive elements, is proposed. For the limit of low nonlinearity, the arising quadratic nonlinear susceptibility is calculated; it is shown how it is controlled by the properties and arrangement of the structure elements as well as by the type and characteristics of the insertion.For the insertions operating in essentially nonlinear regime, when a nonlinear magnetic susceptibility cannot be introduced, an approach is developed for analyzing three-wave coupling processes with a strong pump wave and two weak signals. Peculiarities of coupling, arising from use the insertions with variable resistance or variable capacitance are discussed. Estimates are given that extremely strong nonlinear coupling can be achieved using typical diodes reported in literature.Finally, it is demonstrated how the metamaterial band gap can be tuned, and the resulting metamaterial switching between transmitting, reflecting and absorbing states is described. The details appear to depend drastically on the type of nonlinear components inserted into the resonant conductive elements. Relying on practical estimates, it is predicted that the transmittance of a metamaterial slab can be modulated by several orders of magnitude already using a slab with thickness equal to one microwave wavelength in vacuum.

We develop a theory of vectorial wave coupling in cubic photorefractive crystals placed in an alternating ac-field to enhance the nonlinear response. First we analytically and numerically investigate the dependences of the first Fourier harmonics of the space-charge field, induced in an AC-biased sillenite crystal by a light-interference pattern, on the light contrast m. The data obtained was used to extend the vectorial beam-coupling theory on the whole contrast region. In particular, we proved in the general case that despite of essential differences between thediffusion and AC nonlocal responses the later keeps the light interference fringes straight during the interaction. This fundamental feature allows, under certain restrictions, to reduce the nonlinear problem of vectorial coupling to the known linear problem of vectorial Bragg diffraction from a spatially uniform grating, which admits an exact solution. As a result, the nonlinear vectorial problem can be effectively solved for a number of practically important cases.The developed theory was applied to describe the transformation of a momentary phase changes of one of the input beams into the output intensity modulation (so-called grating translation technique). In contrast to the previous studies, we take into account the change of the space-charge field amplitude across the crystal (the coupling effects). The theory developed is employed to optimize the conditions for the linear signal detection under polarization filtering for the transverse and longitudinal optical configurations. We also analyze the possibility of the linear detection without polarization filtering.Illumination of AC-biased photorefractive BTO crystals with a coherent light beam results in development of strong nonlinear scattering. We investigate the angular and polarization characteristics of the scattered light for the diagonal optical configuration and different polarization states of the pump.

In der vorliegenden Arbeit werden die nichtlinearen optischen Eigenschaften der Materialien Lithiumniobat und Di-Zinn-Hexathiohypodiphosphat aufgrund der Suszeptibilität 3. Ordnung und kleiner Polaronen untersucht. Zudem wird gezeigt, dass die Interferenz verschiedenfarbiger Laserpulse die Aufzeichnung von statischen und dynamischen holographischen Gittern ermöglicht. Ein Teil dieser Arbeit ist in den im Anhang angegebenen 6 Publikationen bereits veröffentlicht. Lithiumniobat wird mit einer Erweiterung des Z-Scan Experiments untersucht, welches die Pulslängenabhängige Messung der nichtlinearen Absorption und der nichtlinearen Brechungsindexänderung ermöglicht. Dabei konnte festgestellt werden, dass bei sehr kurzen Pulslängen von 70 fs ein Effekt der Polaronen auf die nichtlineare Absorption vernachlässigbar ist und die Zwei-Photonen-Absorption die nichtlineare Absorption dominiert. Mit größerer Pulslänge gibt es allerdings Abweichungen zwischen der Theorie der Zwei-Photonen-Absorption und den Messergebnissen. Mit der Entwicklung eines Polaronen-Anregungs-Modells, welches eine polaronische Absorption aufgrund wiederholtem optisch induziertem Hopping annimmt, konnte dieser Effekt konsistent erklärt werden. Die Messungen der nichtlinearen Brechungsindexänderung lassen darauf schließen, dass sowohl freie Ladungsträger als auch kleine Polaronen neben der Suszeptibilität 3. Ordnung einen Einfluss auf die Brechungsindexänderung haben, da eine nichtlineare Abhängigkeit von der Intensität auch bei Pulslängen von 70 fs festgestellt werden konnte. Analog dazu konnte in Di-Zinn-Hexathiohypodiphosphat ein großer Zwei-Photonen-Absorptionskoeffizient festgestellt werden, welcher für Photonenenergien nahe der Bandkante Werte zeigt, die größer sind als theoretischen Überlegungen zeigen. Eine transiente Absorption nach optischer Anregung, gemessen durch ein Anreg-Abtast-Experiment, sowie Literatur legen nahe, dass in Di-Zinn-Hexathiohypodiphosphat gebundene Lochpolaronen durch optische Anregung entstehen können. Durch den hohen Zwei-Photonen-Absorptionskoeffizienten konnte das Aufzeichnen eines kontrastreichen, dynamischen Amplitudengitters mittels Femtosekundenpulsen gezeigt und nachgewiesen werden. Die Kürze der Femtosekundenpulse ermöglicht aber nicht nur das Aufzeichnen eines Zwei-Photonen-Absorptionsgitters aufgrund der hohen Intensitäten, sondern erlaubt zudem die Beobachtung von Interferenz zwischen verschiedenfarbigen Pulsen. In der Zeitspanne der Pulslänge beträgt die Bewegung der Interferenzstreifen, welche in der Größenordnung der Lichtgeschwindigkeit liegt, nur ein Bruchteil der Streifendistanz, sodass das Interferenzmuster eingefroren und beobachtbar erscheint. Somit lassen sich statische Hologramme in holographischen Filmen, wie auch dynamische Hologramme aufzeichnen. Über ein dynamisches holographisches Gitter mittels Zwei-Photonen-Absorption konnte so eine Frequenzkonversion durch Dopplerverschiebung in Lithiumniobat gezeigt werden.