It has been shown in many studies that turbulent flows are highly dependent on their initial conditions. This thesis explores turbulent flow using direct numerical simulation (DNS) in a variety of situations, and culminates in the development of physically realizable initial conditions. The reaction of isotropic homogeneous turbulent flow to the instantaneous insertion of a wall is investigated using two-point correlations. A model with which to predict the behavior of the two-point correlations is also proposed. The proposed model utilizes a reflection technique that with a linear operation, it accurately predicts the behavior of the non-linear two point correlations. The model works exceedingly well for correlations involving wall-perpendicular velocities, but does not predict correlations involving only wall-parallel velocities as well. A vorticity approach is covered, in an effort to highlight which parts of the correlation decomposition are important to the prediction of the correlations after wall imposition. The vorticity study also helps highlight why the proposed linear model predicts the flow. The impact of the initial conditions on axisymmetric contraction flow of turbulent flow is examined, and as a consequence new initial conditions are developed based off of a physically realizable flow condition. The development of the new-initial conditions and the resulting fields are covered, as well as a study on the value of the turbulent decay exponent associated with decay of isotropic turbulent velocity fields.

This PhD thesis is a multi-sited ethnographical study (Marcus 1995) of globalized world through focusing on the social life (Appadurai 1986) of one of the well-known Vedic mantras (the Gayatri Mantra) as a globalized phenomenon and a commodity. Chanting of mantras (Hindu sacred chants in Vedic Sanskrit; pronunciation, intonation and rhythm of which is prohibited to change in the Brahmanic discourse) which had been a local cultural practice, has become a globally known phenomenon. During the globalizing process of their cultural transmission from India to the West and later to the Czech Republic, the mantras have gained new sound forms, new social and cultural contexts, new functions and new meanings. Contemporary cultural productions of mantras are a thick example how the present inter-continental connectedness works in everyday life, music and in the relationship to the Sacred. Selected places on this trajectory will be sites of the fieldwork. The project will research, how the transmission process happens, what music forms it takes, and what meanings are attached to them by their agents.

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<p> Understanding boundary layer transition is fundamental to hypersonic vehicle design as the significant heating induced by the transition process informs the development of vehicle thermal protection systems. Carbon-based thermal protection systems have been shown to decrease thermal loads and delay transition by absorbing thermal energy during ablative mass transfer into the boundary layer. To better understand this process, a high-repetition rate measurement technique is needed to temporally resolve carbon species concentrations as they propagate through the boundary layer at frequencies where boundary layer instabilities occur. Carbon monoxide is a dominant product from the chemical reactions that take place during the ablation process and is the species of interest considered in this work. A proposed approach is applying carbon monoxide two-photon laser-induced fluorescence (CO TP-LIF) at 100 kHz+ during a simulated ablation experiment where CO is injected into the boundary layer of an axisymmetric slender-body cone model in the Boeing/AFOSR Mach 6 Quiet Tunnel (BAM6QT) at Purdue University. To develop this capability, a custom-built optical parametric oscillator (OPO) was designed and used in conjunction with a burst-mode laser system to achieve narrowband excitation of CO at 100 kHz. The OPO was designed, built, and characterized through measurements of cavity energy efficiency, spectral bandwidth, and beam quality. Initial demonstrations to show the OPO could successfully achieve CO LIF were conducted in a vacuum cell at 10 Hz. The feasibility of performing CO LIF at 100 kHz in the BAM6QT was then assessed on a bench-scale using a burst-mode laser, a high speed camera, and an imaging intensifier. CO number densities in a vacuum cell were related to those that would be expected within the boundary layer of a 3 degree half-angle cone in the BAM6QT, and a series of measurements were made at these representative conditions. Appreciable signal levels were attained for single dimensional focused line measurements demonstrating high potential for using this technique in the BAM6QT at 100 kHz. The potential for a two-dimensional planar measurement was also assessed with decent promise for success for planar laser sheets of small dimensions (2 mm tall or less). Additionally, an initial BAM6QT test entry was carried out to gain experience with experimental setup; lessons learned from this experience are examined and discussed. To date, CO TP-LIF has only been applied up to 1 kHz repetition rates. This work represents a 100 fold increase over the current CO LIF state of the art and the first reported measurements, bench scale or otherwise, of 100 kHz-rate CO LIF. This lays the foundation for future CO LIF experiments in the BAM6QT at kHz-MHz repetition rates. </p>

Esta tesis doctoral por compendio de artículos está formada por tres análisis en los que estudiamos observaciones tomadas con el telescopio XMM-Newton de tres fuentes diferentes: La fuente 4U0114+65 es uno de los púlsares más lentos conocidos hasta el momento. Está formado por una donante de alta masa de tipo espectral B1Ia y una NS que la orbita con un periodo de 11.6 d. La NS gira sobre su eje con un periodo de ~ 9350 s. Esta fuente podría ser un magnetar (NS con un campo magnético muy intenso, incluso para una NS). En este trabajo presentamos el análisis de una observación en periodo propietario realizada con el satélite XMM-Newton durante 49 ks, donde hemos estudiado el proceso de acreción, las propiedades del viento estelar y la naturaleza de los pulsos de rayos X. Cen X-3 es un sistema binario compacto de rayos X de alta masa. La acreción sobre el objeto compacto, una NS en este caso, tiene lugar mediante disco de acreción. En este trabajo hemos analizado dos observaciones llevadas a cabo con el telescopio XMM-Newton. Una de ellas tuvo lugar en el año 2001, durante las fases orbitales ∅= 0.0 − 0.37. Esta observación fue tomada durante la salida del eclipse del objeto compacto, cuando la fuente se encontraba en un estado súper-orbital hard-low, hard porque la emisión de rayos X es muy energética y low porque la intensidad es baja. La segunda observación tuvo lugar en el año 2006, durante las fases orbitales ∅= 0.35 − 0.8. En este caso la fuente se encontraba en un estado súper-orbital soft-high, es decir, la luz emitida no es tan energética como en la primera observación pero su intensidad es mayor. Por último, presentamos un análisis de la primera observación tomada con el observatorio XMM-Newton del sistema eclipsante HMXRB XTE J1855−026. La observación tuvo lugar totalmente durante el eclipse de la NS, cubriendo las fases orbitales ∅= 0.00 − 0.11. Hemos comparado nuestro análisis de la fuente en eclipse con uno previo realizado con Suzaku en las fases orbitales previas al eclipse y hemos estudiado el viento estelar retroiluminado de la donante tipo B0I.

This thesis aims to investigate the impact of state fragility on capital inflows and economic growth in Nigeria over the period 1980-2015. In line with existing studies, it adopts an augmented neoclassical growth model where capital is divided into domestic and foreign capital inflows (FDI, ODA and Remittances). Using an autoregressive distributed lag (ARDL) bounds testing approach to co-integration, significant long-run relationship was confirmed between state fragility, capital flows and economic growth. The results reveal domestic capital to be very significant and contribute positively to economic growth. Similarly it was observed that remittances remain a very crucial form of capital flow to Nigeria and that the presence of state fragility makes it more significant. For ODA a positive contribution to economic growth was observed, however, the presence of state fragility renders it insignificant. In the case of FDI, the study found a negative relationship between FDI and economic growth albeit insignificant. However, the presence of state fragility makes it significant but still negative. A negative relationship was also observed between state fragility and economic growth. These findings, implies that while the issue of state fragility needs to be addressed and concerted efforts put into building state resilience, not just for the direct impact of state fragility on the economy, but also its impact on the economy through other channels such as capital flows.

Debris flows occur frequently in remote areas of Great Smoky Mountains National Park, Tennessee. Rainfall gauges are not adequate for modeling infiltration required for triggering debris flows. Weather radar, providing frequently updated, continuous coverage, is a valuable tool for estimating rainfall intensity, duration, runoff, and infiltration. Daily rainfall from a sole gauge was compared with hourly rainfall from the Digital Precipitation Array weather radar product to model infiltration on August 5, 2012, the day before a debris flow was known to have occurred in the 91-km2West Prong Little Pigeon River watershed. Additionally, both gauge and radar data were used for rainfall-runoff-infiltration modeling for a 42-day period in July and August 2012. Runoff and infiltration were simulated using the conventional semi-distributed hydrological model HEC-HMS. A local bias correction of radar rainfall at the gauge location improved correlation between the radar rainfall and the gauge data. Peak daily rainfall for the August 5 storm was 93 mm (gauge) and 98 mm (radar), whereas average daily rainfall for the 42-day period was 10 mm and 7.75 mm, respectively. Over the study period, simulated daily infiltration declined from 28 mm to 0.5 mm for the gauge and from 15 mm to 0.14 mm for radar, indicating essentially saturated conditions on the day of the debris flow.

In recent years, natural, man-made and technological disasters have been increasing in magnitude and frequency of occurrence. Terrorist attacks have increased after the September 11, 2001. Some authorities suggest that global warming is partly the blame for the increase in frequency of natural disasters, such as the series of hurricanes in the early-2000's. Furthermore, there has been noticeable growth in population within many metropolitan areas not only in the US but also worldwide. These and other facts motivate the need for better emergency evacuation route planning (EERP) approaches in order to minimize the loss of human lives and property. This research considers aspects of evacuation routing never before considered in research and, more importantly, in practice. Previous EERP models only either consider unidirectional evacuee flow from the source of a hazard to destinations of safety or unidirectional emergency first responder flow to the hazard source. However, in real-life emergency situations, these heterogeneous, incompatible flows occur simultaneously over a bi-directional capacitated lane-based travel network, especially in unanticipated emergencies. By incompatible, it is meant that the two different flows cannot occupy a given lane and merge or crossing point in the travel network at the same time. In addition, in large-scale evacuations, travel lane normal flow directions can be reversed dynamically to their contraflow directions depending upon the degree of the emergency. These characteristics provide the basis for this investigation. This research considers the multiple flow EERP problem where the network travel lanes can be reconfigured using contraflow lane reversals. The first flow is vehicular flow of evacuees from the source of a hazard to destinations of safety, and the second flow is the emergency first responders to the hazard source. After presenting a review of the work related to the multiple flow EERP problem, mathematical formulations are proposed for three variations of the EERP problem where the objective for each problem is to identify an evacuation plan (i.e., a flow schedule and network contraflow lane configuration) that minimizes network clearance time. Before the proposed formulations, the evacuation problem that considers only the flow of evacuees out of the network, which is viewed as a maximum flow problem, is formulated as an integer linear program. Then, the first proposed model formulation, which addresses the problem that considers the flow of evacuees under contraflow conditions, is presented. Next, the proposed formulation is expanded to consider the flow of evacuees and responders through the network but under normal flow conditions. Lastly, the two-flow problem of evacuees and responders under contraflow conditions is formulated. Using real-world population and travel network data, the EERP problems are each solved to optimality; however, the time required to solve the problems increases exponentially as the problem grows in size and complexity. Due to the intractable nature of the problems as the size of the network increases, a genetic-based heuristic solution procedure that generates evacuation network configurations of reasonable quality is proposed. The proposed heuristic solution approach generates evacuation plans in the order of minutes, which is desirable in emergency situations and needed to allow for immediate evacuation routing plan dissemination and implementation in the targeted areas.