Surface Projection Method for Visualizing Volumetric Data

The goal of this project was to explore, develop, and implement additional visualization methods for volumetric data within MindSeer. This paper discusses the implementation of one such visualization method, the surface projection method, and compares it to other existing methods

Q0906+6930: The Highest-Redshift Blazar

We report the discovery of a radio-loud flat-spectrum QSO at z=5.47 with properties similar to those of the EGRET gamma-ray blazars. This source is the brightest radio QSO at z>5, with a pc-scale radio jet and a black hole mass estimate >10^{10}M_\odot. It appears to be the most distant blazar discovered to date. High energy observations of this source can provide powerful probes of the background radiation in the early universe.Comment: To appear in the Astrophysical Journal Letters. 5pp, 3figure

Dualism and meditation: parallels in German literature and theology from 1910 to 1925

The thesis attempts to provide a detailed discussion of certain aspects of a field which has been largely ignored in literary and theological histories of the early twentieth cen­tury. By means of a close analysis of individual writers and theologians it traces the emergence of a dualistic outlook which draws a sharp division between God and man, the soul and the world. In the case of the creative writers, this dualism not only permeates the ideas and themes contained in their work, but strongly influences their imagery and style. The fifth and sixth chapters endeavour to show that the religious dualism in question is the outcome of a complex interplay of social, political, intellectual and religious factors. The final two chapters examine the ways in which both writers and theologians attempt to overcome the problems discussed in the first part of the thesis. Barth and Bultmann share an a-historical view of a Christ who provides a paradoxical mediation between God and man, and this view is shown to have been prefigured in the works of Trakl and Rilke, both of whom turn to the poetic image as an intangible form of mediation between a comprehensible and an inexpressible dimension. The mediation explored in each case stems from a similar response to the problem of history, and from the attempt to point to an unassailable area immune from the relativising processes of time. Finally, suggestions are made as to how the conclusions of the analysis can be applied more broadly to the literature of the period

Determinants of Under-Five Mortality: Evidence from Zambia

Background: Globally, there are concerted efforts to reduce infant and child mortality. In order to achieve this, efforts are concentrated at identifying cost-effective strategies as many international agencies have advocated for more resources to be directed to the health sector. One way of doing this is to identify and rank-order the socioeconomic factors that affect under-five mortality. This will help in prioritizing factors that need to be manipulated for effective health interventions in the face of competing scarce resources.Methods: We utilised cross-sectional data from the Zambia Demographic and Health Survey (2013-14). The logit regression was employed to empirically investigate the determinants of under-five mortality.Results: The key findings of the multivariate results indicate that mother’s age at birth, child’s gender and number of children under-five, the level of wealth, mother’s level of education, and the region in which a mother resides; smoking cigarettes and the use of contraception are significant determinants of under-five mortality in Zambia.Conclusion: To avert more under-five deaths and enhance child survival, efforts by the Zambian government with the support from other stakeholders in the health sector must be aimed at factors identified by the study. Keywords: Under-five mortality, Empirical investigation, Logit regression, Child survival, Zambia

Low Latency Displays for Augmented Reality

The primary goal for Augmented Reality (AR) is bringing the real and virtual together into a common space. Maintaining this illusion, however, requires preserving spatially and temporally consistent registration despite changes in user or object pose. The greatest source of registration error is latency—the delay between when something moves and the display changes in response—which breaks temporal consistency. Furthermore, the real world varies greatly in brightness; ranging from bright sunlight to deep shadows. Thus, a compelling AR system must also support High-Dynamic Range (HDR) to maintain its virtual objects’ appearance both spatially and temporally consistent with the real world. This dissertation presents new methods, implementations, results (both visual and performance), and future steps for low latency displays, primarily in the context of Optical See-through Augmented Reality (OST-AR) Head-Mounted Displays, focusing on temporal consistency in registration, HDR color support, and spatial and temporal consistency in brightness: 1. For registration temporal consistency, the primary insight is breaking the conventional display paradigm: computers render imagery, frame by frame, and then transmit it to the display for emission. Instead, the display must also contribute towards rendering by performing a post-rendering, post-transmission warp of the computer-supplied imagery in the display hardware. By compensating in the display for system latency by using the latest tracking information, much of the latency can be short-circuited. Furthermore, the low latency display must support ultra-high frequency (multiple kHz) refreshing to minimize pose displacement between updates. 2. For HDR color support, the primary insight is developing new display modulation techniques. DMDs, a type of ultra-high frequency display, emit binary output, which require modulation to produce multiple brightness levels. Conventional modulation breaks low latency guarantees, and modulation of bright LEDs illuminators at frequencies to support kHz-order HDR exceeds their capabilities. Thus one must directly synthesize the necessary variation in brightness. 3. For spatial and temporal brightness consistency, the primary insight is integrating HDR light sensors into the display hardware: the same processes which both compensate for latency and generate HDR output can also modify it in response to the spatially sensed brightness of the real world.Doctor of Philosoph