The Coast Mountains in British Columbia contain over 10,000 km2 of glacial ice. While these glaciers have lost significant mass since the Little Ice Age (LIA; around 300 years before present), the melting rate has significantly increased over the past decade, likely due to the effects of climate change. The purpose of this study was to develop an approach to quantifying the isostatic response to LIA glacier change and investigate how it can further our understanding of the Earth’s rheology through GIA modelling. The Coast Mountains in southwestern British Columbia were chosen due to their significant ice mass loss since the LIA, their location in a tectonically active region, which includes a volcanic arc, and the presence of information of vertical land motion. The GIA models in this study use a wide range of Earth rheological parameters that are then constrained through comparison to observations of vertical land motion in the region. The study used available Global Navigation Satellite System (GNSS) vertical velocity data as the observable from seven GNSS sites in southwestern BC, using a combination of Western Canada Deformation Array (WCDA) and British Columbia Active Control System (BCACS) GNSS stations. Raw data were analyzed using the GIPSY 6.4 software following the Precise Point Positioning processing strategy. Two ice load histories were developed based on gridded estimates of present-day ice thicknesses in the region in order to simulate the change in the surface loading as the glacial ice mass fluctuates over time. Ice Load A used a simple uniform thickness change profile over 3 time-steps based on extrapolated modern melt rates. Ice Load B is more complex and utilized a published profile of glacier change through time basing the magnitude of volume changes on the volume-area scaling relationship with a range of coefficient values. This allowed for a range of ice change magnitudes to be tested. The Earth models used were spherically symmetric Preliminary Reference Earth Models (PREM). Their viscosity structure is based on VM5a for the transition zone and lower mantle, but with variable lithospheric thickness and asthenospheric viscosity. The goodness of fit for the modeled velocities were compared to the observed velocities using a normalized RMS (NRMS) statistic. Ice Load A models had a best fitting lithospheric thickness of 50 km and an asthenospheric viscosity of 2×1019 Pa s. For all variations of Ice Load B, the best fitting model parameters had lithospheric thicknesses ranging from 45 km to 55 km and asthenospheric viscosities between 6×1018 Pa s and 3×1019 Pa s. Corrected GNSS vertical velocity observations were tested to check the effects of interseismic vertical signal and assumed residual GIA from the Cordilleran Ice Sheet. However, the corrections did not improve the NRMS fit. Overall, the asthenospheric viscosity results from this study overlap with all the ranges found in the previous studies while lithospheric thicknesses agree with some past studies. The results of this study generally align with previous work and the current understanding of the Coast Mountains region and can inform a future round of sea-level projections for the region as ice mass loss continues in the Coast Mountains. This study serves to further refine constraints on Earth rheology and can be used to guide future work on GIA in the region. / Graduate

<p> Water drops at their boiling point were projected through a steam atmosphere to strike a surface which was varied in temperature from 300 to 900 degrees Fahrenheit. A high-speed motion picture study of the collision process showed that, except at low surface temperatures, the drop flattened out on impact and rebounded in a state of oscillation. Measurements of the change in drop diameter on--collision indicated that the amount of evaporation due to heat transfer from the surface was extremely small except when the drop extensively wetted the surface. Solution of a mathematical model of the initial impact dynamics and models of heat transfer through a vapour film beneath the drop and by direct liquid-surface contact confirmed experimental observations. </p> / Thesis / Doctor of Philosophy (PhD)

A computational model is developed to simulate the impact dynamics of a droplet on solid substrates with the purpose of predicting the droplet spreading characteristics over time. Previous studies focused on finding relations between the impact parameters and outcome dynamics. A modified approach like the one used in this project revolves around modeling the moving contact lines at the interface in a multiphase flow environment. Focusing on research from an aircraft de-icing point of view, this study is considered a prerequisite in understanding the physics of droplet impact. The primary focus is on extending the application to incorporate super-cooled environments. Development of the model involved the use of the Volume-of-Fluid function coupled with the High-Resolution Interface Capturing scheme to model the moving contact line. The evolution of the moving contact line is modeled with contact angles as their inputs to understand the effect of the surface tension forces. Contact angle modeling is based on the Blended-Kistler method, which captures the contact angle evolution based on the surface tension and capillary number. Preliminary validation performed on the model proves its effectiveness in accurately simulating the impact behavior when compared to the literature, where the spread diameter and height agree well with experiments. The validated model is also compared to the in-house experiments performed at the Cavitation and Multiphase flow laboratory using different substrate materials. The substrates each show unique behavior - Impact on Glass results in the droplet depositing on the surface. Aluminum results in a full rebound and PET-G, results in a drop ejection. Based on inputs from the experiments - contact angles, spread diameter, and the maximum spread $beta$, show good agreement in comparison to the literature. / Master of Science / Computational model developed to simulate the impact dynamics of the droplet on solid surfaces, which predicts the evolution of the droplet over time in order to analyze the effect of the surface and properties of the fluid on the behavior of the droplet on impact. Focusing on research from an aircraft de-icing point of view, this study is considered a pre-requisite in understanding the physics of droplet impact, with potential scope in extending the simulation to applications at temperatures lower than $0^{circ}$ C. A model developed with the help of basic governing equations in fluid mechanics helps capture the effect of interactions between different physical states. The angle at which the droplet interacts with the surface (Contact Angle) and the diameter evolution (d/D) help us understand the effectiveness of the model to simulate droplet impact. Preliminary validation of the model is performed with respect to the literature where the droplet diameter evolution and the height variation match well with the experiments, which was the major criterion in determining the accuracy of the model. This model is compared to the in-house experiments performed at the Cavitation and Multiphase flow laboratory on different surfaces such as Glass, Aluminum, and Plastic (PET-G). The surfaces each show unique behavior with impact on Glass having the droplet deposit on the surface, aluminum resulting in the droplet bouncing after hitting the surface, and PET-G resulting in a small droplet being ejected from the bigger droplet which eventually deposits on the surface. Conclusions from the comparison between the experiments and the numerical simulation show how the model is effective in capturing the impact behavior on surfaces like glass in comparison to surfaces like Aluminum in this case that repels water.

In the last few years, engagement in medical care among individuals living with HIV has become a major priority among HIV medical providers and public health researchers. Engagement in medical care is an important concept as it involves the process of linking newly diagnosed individuals into medical care and retaining those individuals in care throughout the course of their infection. Although there have been major advances in the management of HIV, like the advent of Highly Active Antiretroviral Therapy, morbidity and mortality due to HIV cannot be fully reduced if the individual does not optimally retain in care. Retention in HIV medical care has become an emerging topic in HIV research, but there still remains a scarce amount of research on how to properly define retention, understand its predictors, and how it impacts HIV outcomes. The purpose of this dissertation was to evaluate retention in HIV medical care among individuals diagnosed with HIV and seeking care at an urban infectious disease clinic in Kentucky. The three specific aims of this dissertation were to: (1) compare methods in measuring retention in HIV medical care; (2) determine the predictors of poor retention in care and assess the effect of non-HIV related comorbidities have on retention over time; and (3) determine the impact early retention to medical care has on time to viral load suppression and rebound among individuals initiating Highly Active Antiretroviral Therapy. A retrospective cohort study was conducted employing a medical chart review, and patients who sought HIV care at the Bluegrass Care Clinic between January 1st 2003 and May 1st 2011 were eligible for the study. There were 1,358 patients included in the study and these individuals were followed until December 31st, 2011. The results suggested that individuals living with HIV should seek care at least once every six months (visit constancy) and that only 48.6% of the study population obtained optimal retention over time. Over time the rate of retention decreased among the study sample and those with optimal retention were more likely to suppress their viral loads compared to poor retainers.

The concept of resource nexus is an acknowledgement of the interconnections between the uses of natural resources. This research will further the work done on the resource nexus by examining the multiple effects of measures taken in the Indian textile industry to lower the costs incurred due to the implementation of Zero Liquid Discharge (ZLD). ZLD combines a variety of technologies to cease the discharge of untreated water from production processes to the surrounding area. The paper will, based on surveys answered by an IKEA supplier and four of IKEA’s sub-suppliers of textile in India, present a multiple case study of possible multiple effects of projects undertaken to lower the increased cost of manufacturing with ZLD. Building on the multiple case study, and marrying it with the knowledge of the multiple benefits of energy efficiency improvements, the Value Added Water (VAW) tool, and the rebound effect, this paper constructs and offers a Multiple Effects Framework (MEF) for measures taken in factories as a response to the increased cost of manufacturing with ZLD. The framework handles both quantifiable and non-quantifiable multiple effects of measures taken, such as changes in resource use (water, energy, chemicals, materials), productivity and work environment. The MEF aggregates a more comprehensive picture of the overall effects of measures taken to adapt to the increased costs associated with ZLD in the textile supply chain, and can to a certain extent be applied to other factories facing a future mandate for ZLD. When changed accordingly, the framework can also be applied to other situations and industries as a decision-making and evaluation tool. In order to deepen the understanding of customer expectations and future trends, interviews were made with IKEA co-workers and a consultant involved with the factories investigated. Lessons learnt by IKEA and the consultant regarding ZLD implementation and the resource nexus are presented for internalization by factories, customers and authorities.

The aim of this research is to assess the material properties of concrete like modulus of elasticity, compressive strength, and Poisson’s ratio using various nondestructive Testing (NDT) methods like Ultrasonic Pulse Velocity (UPV) and Rebound Hammer (RH). Assessment of material properties of concrete is very important as they are used for structural design process. Various NDT methods are applied to ensure the quality of concrete specimens but they can also be used to find material properties. UPV is a NDT method which is used to test the internal condition of the concrete specimen. RH is a surface hardness testing method and can be used to test the homogeneity of the specimen. For this study, several batches of concrete samples with three different design strengths of 6000 psi, 8000 psi, and 12000 psi were casted. Modulus of elasticity and Poisson’s ratio were calculated from UPV P-wave and S-wave velocities. A Nomogram was developed by combining the longitudinal ultrasonic pulse velocities, rebound numbers, and compressive strengths measured from UPV, RH, and compressive strength tests respectively. This combined NDT correlation curve (Nomogram) can be used to estimate compressive strength of concrete if UPV and rebound values are known. The accuracy of these NDT methods were determined by comparing estimated strength to the actual strength. Furthermore, the effect of moisture content on UPV and rebound values was reviewed and also studied dynamic modulus of elasticity and its relation with static modulus of elasticity of the concrete was investigated for better understanding.

Em obras de fundações por estacas cravadas, os diferentes comprimentos finais das estacas refletem a variabilidade natural do terreno, e variam de acordo com o critério de paralização da cravação, normalmente baseado em medidas de nega e repique elástico. Pouco se tem aproveitado desses registros para o controle da resistência mobilizada na fundação ao final da cravação, devido à limitação da aplicação das fórmulas dinâmicas e ao desconhecimento de alguns parâmetros. Em muitos casos de controle de capacidade de carga, apenas é realizada a aferição de um fator de segurança pontual, obtido via prova de carga. Neste trabalho, é apresentado um procedimento de controle de capacidade de carga de fundações por estacas cravadas, baseado em registros de nega e repique elástico, a partir de fórmulas dinâmicas, que possibilitam a estimativa da resistência mobilizada ao final da cravação em todo o universo de estacas de uma obra. Este procedimento proposto foi aplicado em um estudo de caso de uma obra em um porto em Santa Catarina. Nesta obra foram cravadas 2506 estacas pré-moldadas de concreto, controladas por nega e repique elástico, registrados em todas as estacas no final da cravação. Neste conjunto de estacas foram executadas 74 provas de carga dinâmica, com energia crescente, e quatro provas de carga estática. Neste caso de obra controlada, os resultados mostraram que o procedimento adotado, baseado na utilização de fórmulas dinâmicas, com parâmetros calibrados a partir dos resultados das provas de carga dinâmica, permitiu estimar valores de resistência mobilizada ao final da cravação das 2506 estacas da obra, que apresentaram um valor médio próximo ao valor médio encontrado nas 74 estacas ensaiadas. Além disso, o coeficiente de variação dos valores de resistência mobilizada de todas as estacas da obra foi da ordem de 16,0%, similar ao coeficiente de variação de 14,7%, obtido nos resultados das provas de carga dinâmica. / The different final lengths of driven piles reflect the natural variability of the soil, and are dependent of the driving controls based in the measurements of the final set and elastic rebound. Normally these measurements are not used to predict the ultimate capacity of pile foundations, at the end of driving, due to the limitation of the dynamic formulas and the lack of some parameters. In many cases, the pile capacity control is based on a determination of a single safety factor, obtained from pile load tests. In this work, it is proposed a procedure to control the ultimate capacity of driven piles, based on the results of the final set and the elastic rebound, and dynamic formulas, which allow the estimation of the mobilized resistance at the end of driving of all piles driven in a particular project. This procedure was applied in a case study of a port in Santa Catarina. In this case, 2506 precast concrete piles were driven, and controlled by the elastic rebound, recorded at the end of driving. Also, dynamic load tests, with increasing energy, were performed on 74 piles, and static load tests were carried out on four piles. The results showed that this procedure adopted, based on the use of dynamic formulas calibrated using the results of dynamic load tests, is capable to estimate the values of mobilized resistance along all piles at the end of driving. The average result of the mobilized resistance of the 2506 piles was close to the average value found by the results of the 74 pile dynamic load tests. Also, the coefficient of variation of the mobilized resistance of all piles was around 16.0%, similar to the coefficient of variation of 14.7%, obtained by the dynamic load tests.

A mensuração da pressão intraocular (PIO) é essencial para o exame oftálmico, pois permite o diagnóstico de doenças oftálmicas como uveíte e glaucoma, além de auxiliar no monitoramento das cirurgias intraoculares. Objetivou-se comparar a tonometria de rebote com a tonometria de aplanação em equinos. Além disso, determinar a reprodutibilidade dos valores obtidos em ambos os aparelhos. A PIO foi aferida em 30 equinos da raça Crioula, machos ou fêmeas, com idade entre um e 16 anos utilizando o tonômetro de rebote (TonoVet®) e o tonômetro de aplanação (Tonopen Avia®). Previamente a aferição da PIO, todos os animais foram submetidos ao exame oftálmico incluindo, avaliação dos reflexos pupilares, teste da lágrima de Schirmer, prova da fluoresceína e biomicroscopia com lâmpada de fenda portátil. Foram utilizados apenas bulbos oculares hígidos. A análise estatística foi feita com ANOVA e teste t de Student. A reprodutibilidade foi avaliada pelo cálculo do coeficiente de correlação intraclasse (ICC). A média da PIO foi de 26,16 ± 5,13 mmHg utilizando o tonômetro de rebote e de 22,55 ±7,32 mmHg com o tonômetro de aplanação. A média da PIO de acordo com o avaliador utilizando o tonômetro de rebote foi de 25,27 ± 4,9 mmHg para o examinador A, 25,80 ± 5,2 mmHg para o examinador B e de 27,40 ± 5,1 mmHg para o examinador C. Com o tonômetro de aplanação as médias obtidas foram de 20,03 ± 4,5 mmHg com o examinador A, 19,67 ± 6,0 mmHg com o examinador B e de 27,97 ± 10,3 mmHg com o examinador C (p<2,3). O ICC foi de 0,18 para o tonômetro de aplanação e de 0,41 para o tonômeto de rebote. Os valores da pressão intraocular média obtidos com o tonômetro de rebote são superestimados quando comparados aos valores obtidos com o tonômetro de Tonopen Avia® em equinos saudáveis. Comparativamente ao Tonopen Avia® os valores obtidos com o Tonovet® demonstraram maior reprodutibilidade. / The measurement of intraocular pressure (IOP) is essential for the ophthalmic examination, as it allows the diagnosis of eye diseases such as uveitis and glaucoma, as well as aid in the monitoring of intraocular surgery. This study aimed to compare the mean intraocular pressure (IOP) values in horses obtained by three different examiners using the rebound and applanation tonometer’s. Each examiner measured the IOP of 30 “Crioulo” horses, males or females, aged one to 16 years old, using rebound tonometer and applanation tonometer. Previous to the experiment an ophthalmic examination was performed in horses. Only animals without alterations were selected. Three veterinarians measured IOP with rebound (Tonovet®) and applanation tonometer’s (TonoPen Avia®). Comparisons were made using ANOVA and student t test. Intraclass correlation coefficient (ICC) was calculated for reproducibility. IOP measurements resulted in mean values of 26.16 ± 5.13 mmHg for rebound tonometer and 22.55 ±7.32 mmHg for applanation tonometer. These values were different on statistical analysis. Rebound tonometer mean values, according with the examiner, were: A 25.27 ± 4.9 mmHg, B 25.80 ± 5.2, C 27.40 ± 5.1 mmHg. For applanation tonometer the mean IOP for examiner A (20.03 ± 4.5 mmHg), B (19.67 ± 6.0 mmHg), C (27.97 ± 10.3 mmHg). With the Tonopen Avia® tonometer examiner C measured higher IOP’s than examiners A and B. Intraclass correlation coefficient was 0.41 for rebound tonometer was 0.18 for applanation tonometer. It was observed that the values obtained with the Tonovet® were overestimated compared to Tonopen Avia® in healthy horses. When compared with Tonopen Avia® values obtained with the Tonovet® showed a higher reproducibility.

A survey of residential solar photovoltaic (PV) adopters in Texas was administered and the results are presented and discussed. A 40% response rate was achieved and 365 complete responses were received. In addition to demographics, the survey uncovered aspects related to the decision-making process, information search, financial attractiveness of PV, and post-installation experience. Peer-effects did not have a large influence on the adoption of residential PV in Texas, but the potential for increasing the number of communication/information channels to increase the adoption rate of PV exists. Adopters experienced little uncertainty at the time of PV installation because sufficient dependable information was available during the search process. Overall, they are satisfied with PV. Contextual factors, such as income and the ability to purchase a PV system rather than lease one, influence behavior. Those who decreased electricity consumption post-adoption were more motivated to adopt by environmental concern and a general interest in energy than those who increased electricity consumption post-adoption. Those who experienced behavior changes also experienced an increase in awareness of electricity use post-adoption, while those who did not experience a behavior change reported no change in awareness post-adoption. Change in awareness of electricity use is less dependent on the attitudinal and contextual factors, such as environmental concern, motivation for adoption, age, and income, that influence consumption change. The potential for further analysis of the survey results is great and will likely yield additional conclusions about the consequences of the adoption of PV. Coupling the survey results with historical electricity bill data will yield stronger conclusions about behavior change. Surveying geographical areas outside of Texas is recommended. / text

The human society exerts its influence on the ecosystem through economic activities. While the robustness of an economy manifests through its industrial structure, human impact on nature is well represented by an economy's energy consumption patterns. Therefore, evaluating the industrial structure and unraveling its interconnection with energy consumption is crucial for achieving sustainable development. In this dissertation, I address the topic from several perspectives. First, I start with an exploratory analysis on the industrial structure itself, developing an easy measure, revealed comparative dependence (RCD), to compare regional dependence on sectors. Building on the RCD measure, I indirectly evaluate the economic resilience of U.S. states by quantifying their economic diversity. Second, I bring the measure for industrial structure into context with energy consumption patterns. RCD is used to characterize sector interactions, which are then used to explain the historical trend of regional energy consumption. I find that while the expansion of low energy intensity sectors does reduce energy use, these sectors' level of interaction with other sectors also plays a key role in determining energy use. As a third step, I investigate how regional structure affects an economy's response towards energy efficiency improvements, i.e., the economy-wide rebound effect. My regional computable general equilibrium (CGE) model proves that production-side energy efficiency improvement induces moderate rebound effects, while feeding back into the industrial structure by changing sectoral production scale in different directions. I also identify sectors being able to trigger different levels of energy saving and energy rebound, and explore the mechanism for their impact propagation throughout the industrial structure. This study establishes the linkage between regional industrial structure and energy consumption from different perspectives. From the scientific perspective, it improves the fundamental understanding of how industrial structure and energy consumption are intricately connected to each other. From the policy perspective, it informs policy makers of the importance of considering sector interaction when designing energy policies, as well as the effectiveness of efficiency measures in achieving energy conservation.