Origami-adapted mechanisms form the basis of an increasing number of engineered systems. As most of these systems require the use of non-paper materials, various methods for accommodating thickness have been developed. These methods have opened new avenues for origami-based design. This work introduces approaches for the design of two new classes of thick-origami systems and demonstrates the approaches in hardware. One type of system, called "conceal-and-reveal,'' is introduced, and a method of designing these mechanisms is developed. Techniques are also developed for designing folding printed circuit boards which are fabricated from a single sheet of material. This enables areas of regional flexibility, leaving other areas stiff. This allows components to be attached to stiff regions and folding to occur at flexible regions. An optimization method is presented to design the geometry of surrogate hinges to aid in monolithic origami-based mechanisms such as flexible PCBs. Examples are shown which demonstrate each of these new techniques.

Increasingly stringent water quality regulations concerning microbiological parameters govern the use of groundwater resources that are vulnerable to mixing with surface waters. These drinking water sources are at higher risk for infiltration by pathogenic microorganisms, including the oocysts of the human enteroparasite Cryptosporidium spp. Cryptosporidium can cause severe gastroenteritis in humans, and the characteristics of Cryptosporidium oocysts, including low infectious dose, high resistance to inactivation, and long survival in the environment pose a significant risk to public health if present in treated drinking water. Bacillus subtilis is widely used as a surrogate for biocolloid transport in saturated porous media, and recognized as a conservative indicator for the transport of Cryptosporidium parvum oocysts during filtration. However, no study has directly compared the transport of spores from different strains within the Bacillus subtilis species. Strain variability has the potential to impact retention in porous media based on differences in size and electrophoretic mobility. The transport behaviour of four strains of Bacillus subtilis (wild-type and laboratory type, subspecies subtilis and subspecies spizizenii; 1.9 to 2.9µm diameter) is contrasted in this research to two sizes of fluorescent polystyrene microspheres (1.1µm and 4.5µm diameter) through packed saturated crushed quartz sand. A peristaltic pump was used to introduce (bio)colloids into the duplicate column apparatus at a loading rate of 0.1m/day. (Bio)colloid removal was assessed and compared by constructing breakthrough curves of normalized concentrations and box-and-whisker diagrams of percent removal of Bacillus subtilis strains. Under unfavourable conditions minimal reduction (<0.22log10) in effluent spore concentration was observed over the column depth of 15cm. In favourable attachment conditions up to 0.69 log10 reduction was observed but the sampling schedule employed was insufficient to clearly identify a pseudo steady-state plateau. An analysis of variance was used to determine the statistical significance of spore strain, subspecies, and type. A significant difference between the four strains was observed at the lower ionic strength, with spore subspecies and type affecting spore removal in unfavourable conditions (p < 0.05). Some sensitivity to settling and laboratory storage suggests that standardized sample handling procedures are required. Differences observed here between the strains of Bacillus subtilis spores indicate that riverbank filtration performance assessments and drinking water treatment plant process demonstrations may benefit from a recommended strain for use.

Surrogate motherhood abounds in nineteenth-century fiction. Governesses, nurses, aunts, and close family friends often form strong attachments with young girls, guiding them through life and their comings-of-age. Many surrogate mothers train their “daughters” according to the rules of societal expectations that mothers and daughters have cordial, respectful relationships, where the mother is unselfish, loving, and sympathetic toward her respectful, obedient, honest daughter. Many other nineteenth-century novels, however, depict surrogate mothers who are cruel, selfish, and unloving toward their “daughters.” While the role of the surrogate mother exists in various forms, it is regardless a strong presence in nineteenth-century fiction that leads daughters to choose to become surrogate mothers themselves.

Increasingly stringent water quality regulations concerning microbiological parameters govern the use of groundwater resources that are vulnerable to mixing with surface waters. These drinking water sources are at higher risk for infiltration by pathogenic microorganisms, including the oocysts of the human enteroparasite Cryptosporidium spp. Cryptosporidium can cause severe gastroenteritis in humans, and the characteristics of Cryptosporidium oocysts, including low infectious dose, high resistance to inactivation, and long survival in the environment pose a significant risk to public health if present in treated drinking water. Bacillus subtilis is widely used as a surrogate for biocolloid transport in saturated porous media, and recognized as a conservative indicator for the transport of Cryptosporidium parvum oocysts during filtration. However, no study has directly compared the transport of spores from different strains within the Bacillus subtilis species. Strain variability has the potential to impact retention in porous media based on differences in size and electrophoretic mobility. The transport behaviour of four strains of Bacillus subtilis (wild-type and laboratory type, subspecies subtilis and subspecies spizizenii; 1.9 to 2.9µm diameter) is contrasted in this research to two sizes of fluorescent polystyrene microspheres (1.1µm and 4.5µm diameter) through packed saturated crushed quartz sand. A peristaltic pump was used to introduce (bio)colloids into the duplicate column apparatus at a loading rate of 0.1m/day. (Bio)colloid removal was assessed and compared by constructing breakthrough curves of normalized concentrations and box-and-whisker diagrams of percent removal of Bacillus subtilis strains. Under unfavourable conditions minimal reduction (<0.22log10) in effluent spore concentration was observed over the column depth of 15cm. In favourable attachment conditions up to 0.69 log10 reduction was observed but the sampling schedule employed was insufficient to clearly identify a pseudo steady-state plateau. An analysis of variance was used to determine the statistical significance of spore strain, subspecies, and type. A significant difference between the four strains was observed at the lower ionic strength, with spore subspecies and type affecting spore removal in unfavourable conditions (p < 0.05). Some sensitivity to settling and laboratory storage suggests that standardized sample handling procedures are required. Differences observed here between the strains of Bacillus subtilis spores indicate that riverbank filtration performance assessments and drinking water treatment plant process demonstrations may benefit from a recommended strain for use.

Thesis (Ph.D.(Practical Theology))--University of Pretoria, 2008. / Includes bibliographical references (leaves 306-337)

Magister Legum - LLM / The development of assisted reproductive technology (ART) has radically changed the landscape of the conventional family. It has permitted a platform for the creation of families and family structures with tremendous diversity in their demographic characteristics. It has also changed the way in which individuals become parents. The advances in medical and scientific fertility treatments have meant that for many the dream of having a child of their own has now become a real possibility. Public perception and attitudes towards infertility treatments and more latterly surrogacy has changed tremendously and becoming increasingly acceptable. While there are those who have celebrated the advancement in reproductive technologies and potential freedoms that this may contain, ART has opened the proverbial Pandora's Box amongst scholars and the public policy makers, principally in the area of rights.

Pre-ignition is a type of irregular combustion that occurs in boosted direct injection gasoline engines when one or more auto-ignition events occur before to spark ignition. Due to the direct injection of fuel into the cylinder, some liquid fuel may splash off the walls, dragging along lubricating oil. The self-ignition of liquid fuel/lubricant droplets is one of the pre-ignition sources studied. To test this stochastic behavior in a controlled manner, we examined the auto-ignition of a single droplet of a hexadecane-fuel mixture, with hexadecane serving as a surrogate for the lub oil. This experiment involved suspending a single hexadecane-fuel mixture droplet on a thermocouple bead in preheated air at temperatures ranging from 150 to 300 ° C over a wide range of pressures (4-30 bar). Various fuels with RON values ranging from 0 to 120 were blended with hexadecane at varying volume percentages of fuel in hexadecane from 0% to 100% to determine the droplet's time to ignition, denoted by TI. TI was determined by concurrently recording the history of the droplet temperature and imaging it at high speed. The ignition of the droplet is triggered by the self-ignition of the combustible mixture created by the vapor of the hexadecane-fuel mixture reacting with the heated ambient air surrounding the droplet. The increase in RON increased the TI as high RON fuels are difficult to ignite. However, the TI of the mixture depended on the fuel mixture properties even when the RON of the mixture was relatively high. Furthermore, the metal additives were added to the oil surrogate to investigate their effect on getting a pre-ignition event. The lubricant oil additives were phosphate, magnesium, and calcium. These additives were mixed with hexadecane at different concentrations. The experiments were conducted in a constant volume combustion chamber at 300 ⁰C temperature and the pressure was varied from 5 to 15 bar. The resulting TI were then compared with the TI of pure hexadecane. The results showed that addition of phosphate reduces the chances of getting a pre-ignition event, magnesium showed neutral effect while calcium enhanced the chances of getting a pre-ignition event.

A computationally efficient multilevel decomposition and optimization framework is developed for application to automotive structures. A full scale finite element (FE) model of a passenger car along with a dummy and occupant restraint system (ORS) is used to analyze crashworthiness and occupant safety criteria in two crash scenarios. The vehicle and ORS models are incorporated into a decomposed multilevel framework and optimized with mass and occupant injury criteria as objectives. A surrogate modeling technique is used to approximate the computationally expensive nonlinear FE responses. A multilevel target matching optimization problem is formulated to obtain a design satisfying system level performance targets. A balance is sought between crashworthiness and structural rigidity while minimizing overall mass of the vehicle. Two separate design problems involving crash and crash+vibration are considered. A major finding of this study is that, it is possible to achieve greater weight savings by including dummy-based responses in optimization problem.

Choosing a surrogate to make medical decisions for a patient is an emotionally challenging task. In hospital settings, it is estimated over 86% of life saving medical decisions have been made by a surrogate (Swigart, Lidz, Butterworth, & Arnold, 1996). For the marginalized populations of lesbian, gay men, bisexual, and transgender persons (LGBT), decisions are especially difficult, compounded by issues of discrimination, lack of legal support, level of relationship commitment,, and complicated disclosure to family and medical professionals (Riggle, Rostosky, Prather, & Hamrin, 2005). Limited research has been presented regarding environmental and social factors that impact the choice of a surrogate decision-maker for a LGBT individual. This in-depth literature review will examine factors influencing individual surrogate choice, identify obstacles and gaps in the literature findings, and explore services required by the LBGT population.

The equations governing the thermodynamic behavior of a military aircraft have been implemented by the Air Force Research Lab (AFRL) and other Integrated Vehicle Energy Technology Demonstration (INVENT) contributors into a cohesive, adaptable, dynamic aircraft simulation program in Mathworks' Simulink®. The resulting model known as the "Tip-to-tail" model meets the design specifications set forth by the INVENT program. The system consists of six intimately linked subsystems that include a propulsion subsystem (PS), air vehicle subsystem (AVS), robust electrical power subsystem (REPS), high power electric actuation subsystem (HPEAS), advanced power and thermal management subsystem (APTMS), and a fuel thermal management subsystem (FTMS). The model's governing equations are augmented with experimental data and supported by defined physical parameters. In order to address the problems associated with the additional power and thermal loads for in more electric aircraft (MEA), this research utilizes exergy analysis and mission-integrated synthesis/design optimization to investigate the potential for improvement in tip-to-tail design/performance. Additionally, this thesis describes the development and integration of higher fidelity transient heat exchanger models for use in the tip-to-tail. Finally, the change in performance due to the integration of new heat exchanger models developed here is presented. Additionally, this thesis discusses the results obtained by performing mission-integrated synthesis/design optimization on the tip-to-tail using heat exchanger design parameters as decision variables. These results show that the performance of the tip-to-thermal management subsystems improves significantly due to the integration of the heat exchanger models. These results also show improvements in vehicle performance due to the mission-integrated optimization. / Master of Science