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Getting lost in nature, I can sense the unfixity of its countless forms and processes. Recurring patterns at micro and macro scale arise from creative and destructive forces in space and time; reality appears simultaneously constant and impermanent. My thesis work, a wheel inside a wheel, explores the self in relation to contemporary conceptions of reality. I look at static and dynamic representations of stripped-down patterns modeled from nature, like circular bursts, splintering branches, or the meander of a wave. The action-based works on paper and cloth leverage invisible forces and signal permanency and physical embodiment, deepened through an engagement with archetypal materials. Time-based media renders an altogether separate point of view. Presenting documentary footage alongside artifacts of this abstraction practice, I speculate on the role sensing and recording technologies have in altering perceptions and observations of reality.

The purpose of this phenomenological study was to gain a better understanding of the experiences of medically disqualified student-athletes (MDSA) at National Collegiate Athletic Association (NCAA) Division I institutions. This study is significant because few studies have examined MDSAs, yet they present concerns around career-ending injuries. Drawing on the Kübler-Ross Model of Death and Dying (1969) framework, this study examined if MDSAs have faced experiences in stage-like forms such as denial, anger, bargaining, depression, and acceptance. This study called the attention of athletic administrators to examine and develop support resources for this often-overlooked student-athlete group. Over five chapters, this dissertation presents summarized literature, discussed assumptions, answered four research sub questions and a central research question, providing results through interpretive phenomenological analysis (IPA), and recommended best practices. Chapter 1 presents a brief overview of the study, the NCAA, medically disqualified student-athletes, and Kübler-Ross Model of Death and Dying. The history and context of student-athletes, injuries and social support are summarized in Chapter 2, along with a case for qualitative methodologies. IPA and study methodologies are discussed in detail in Chapter 3. Results are presented in Chapter 4 and explore the depth of each research sub question. Chapter 4 presents an understanding of athletic identity, need for social support, psychological reaction, and compare these reactions to Kübler- Ross Model of Death and Dying. Chapter 5 examines the central research question and how the sub questions play major roles in understanding MDSAs experience after sports. Using the themes, best practices are presented for administration to better support medically disqualified student-athletes.

Distraction happens to everyone at some point in time. Diverted attention while driving can have serious consequences, and being sidetracked while talking on the cellphone can cause one to forget where the car keys were laid down at home. Distraction at church during a worship service can affect one’s relationship with God and others. Personal motivations, pre-existing conditions, and duration of time contribute to how a person will interact with a disturbance of attention; likewise, factors of biology, technology, values, and mores can influence the power of partial attention. The purpose of this phenomenological study is to examine the lived experiences of pastors and congregants at Faith Community Church in Kissimmee, Florida, and the impact of this study can potentially increase a grasp on distraction and its effect upon a congregation. This study proves a correlation exists between an object, the phenomena of distraction, and a person’s spiritual journey.

This thesis offers a preliminary argument for materiality as the primary medium through which landscape architecture is experienced. An original theory, Transformative Materiality, posits that landscape experience may be heightened, making people more aware of and engaged with their surroundings, if design encourages the changing of materials over time through temporal landscape processes (such as erosion and deposition). Resulting landscape phenomena may translate into passive education about the effects of naturalistic material transformation. And any gained experiential knowledge of the landscape, might, in turn, become a source of meaningful, personal connection to the landscape, potentially inspiring appreciation and stewardship. The theoretical development and argumentation for Transformative Materiality is preceded by its application in the final thesis design project, to provide a basis for common reference. The Beach Outfalls Challenge competition serves to provide a site and problem: the Mississippi commercial beach system, and stormwater management through the immediate beach environment. Three materials, sand, wind, and water, are studied in relation to landscape processes that are purposefully employed to encourage change in the landscape’s material form over time. The final design is a landscape technology that harnesses material processes in order to perform environmental services of cleaning stormwater and creating new habitat, while allowing such processes to diversify material form for a range of phenomena and consequent opportunities for experiential education that may lead to a holistic understanding of the landscape as a dynamic, responsive system.

A Look to Burst the Brightest Neon Hearts is an inquiry, via constellation of stories diffuse in structure and subject matter, into the various (and really weird) phenomena comprising contemporary American existence. Cumulatively, the stories seek to: (1) kick up, like bottom feeders searching biogenous sediment, an underlying value system, and (2) explore how language both breastfeeds and like, weans this value system-e.g., what dark matter is it that tethers bromances to reality TV? Quantum mechanics to pop music? How can a country be responsible for both the world's highest incarceration rates, and OKCupid? These stories also explore various American conceptions and embodiments of love, plotting out a strange attractor of cultural reflection and refraction.

In the following text I describe the origin and the process of my thesis works. Phenomena is a body of work curated from hundreds of paintings made over the last nine months. Each painting is the result of chance, conscious decision-­‐making, fixed laws of natural phenomena (evaporation, surface tension, capillary action), and its surrounding environment. I introduce how I learned to see my surroundings and how it directly relates to my process of making phenomenological paintings. I explain how the works evolved to reflect a transformation from working in a highly controlled manner to accepting what I could not control. Paramount to this transformation is an exploration and awareness of my decision making process.

My practice is concerned with the effects of painting and drawing on perceptualsystems. The purpose of this research is to examine our material relationship to theworld and to consider how we might shift our views in order to broaden our perceptualexperiences. In this thesis I will examine the collaborative role of materials in our dailylives and provide examples of how these interactions might affect the ways in which weengage with life, art, and artistic practice.

Blood clotting, or thrombosis, is an interesting biological application for computational fluid dynamics. Existing numerical thrombosis models have previously been shown to be effective for low shear rates and simple geometries. For these models to be used in biomedical applications such as the design of rotary blood pumps, however, they must first be experimentally validated for high shear rates and complex geometries. In this study, we test the ability of a numerical thrombosis model to predict thrombosis related phenomena in a high shear flow by creating a geometry similar to that of a rotary blood pump. We have applied an existing numerical thrombosis model to an annular gap between rotating concentric cylinders, a geometry that is closely related to rotary blood pumps. Additionally, we created a physical model of the same geometry and exposed blood to a range of shear rates in both the empirical and numerical model. The empirical and numerical results are compared in order to evaluate the ability of the numerical model to predict thrombosis in similar geometries, such as high shear blood handling pumps. Fluent was used to solve the coupled convective-diffusion equations along with user defined equations that include production and consumption of 7 species critical to thrombosis. These equations, along with equations of fluid motion, were solved iteratively within the Fluent solver. All reaction constants were from previously published work. At each of the shear rates and exposure times tested, the numerical model calculated platelet deposition, platelet-platelet aggregation and the two-dimensional distribution of three primary agonists (ADP, thromboxane and thrombin) in addition to the standard fluid variables (velocity, pressure, shear rate, etc.) A physical model was designed and constructed to control the shear rate to which blood is exposed. An annular gap of 360μm was chosen in order to induce a shear rate of up to 10,000 s-1 while maintaining laminar flow. In a series of experiments, fresh, heparinized, bovine blood was exposed to a constant shear rate ranging from 1,000 to 10,000 s-1 for 120 seconds. Prothrombin time (PT) and activated partial thromboplastin time (APTT) of the blood was then measured for each stress level. While the observed changes in thromboembolitic potential (as measured by PT and APTT) of the whole blood test samples qualitatively correspond to platelet activation and agonist concentration predicted by the numerical model, further work is needed to quantitatively verify the numerical model. Thrombosis models based on coupled convective-diffusion equations show promise, but need further refinement and validation before they can be trusted to authoritatively predict thromboembolitic potential.

Mistuning, small differences among sectors of bladed disks, is unavoidable because of manufacturing tolerances and in-service wear and tear. Mistuning can be very dangerous because it might cause energy localization and early failure of certain blades. Finite element analysis is computational formidable for mistuned bladed disks because the loss of cyclic symmetry requires analysis of the full sector model and mistuning can be totally random. Hence, a great amount of research effort have been devoted to develop efficient and accurate reduced-order structural models. Real bladed disks are usually operated in high pressure and high temperature air flows. Although linearized frequency domain aerodynamic models have been developed in recent years, utilizations of these aerodynamic models with high fidelity structural models of mistuned bladed disks are limited. A new iterative aeroelastic coupling procedure is developed in this dissertation. A group of tuned system modes are used to calculate unsteady aerodynamic modes. Vibration eigenvalues and mode shapes are obtained by iterative computation. It is shown that free and forced aeroelastic responses of mistuned bladed disks can be significantly different from structural-only responses. Also, blade-disk interface constraint modes are needed if cantilevered-blade normal modes are used to calculate unsteady aerodynamic forces. The aerodynamic model has been extended from subsonic regime to transonic regime by employing the upwinding technique. Parametric studies show that inflow incidence angle and Mach number can relieve the severity of mode localization. Also, inflow Mach number changes the sensitivity of mistuned forced response to mistuning levels. In this dissertation, a new hybrid technique is also developed to predict the iteration steps needed to obtained converged results. It is of great importance because the iterative aeroelastic calculation consumes a great amount of computation time. Several critical ratios are proposed to characterize the aeroelastic system. The predicted results are validated with actual aeroelastic computation results, and Monte Carlo simulations are conducted to study effects of important factors on the convergence history. It is found that among these critical ratios, the aerodynamic ratio and the aerodynamic gradient ratio are the two most important factors.

The goal of this research is to advance a fundamental understanding of the principles governing zeolite dissolution---a scientifically challenging problem that is of fundamental importance to a variety of environmental processes including wastewater stream treatment, radioactive waste immobilization, and petroleum reservoir acidization. The stimulation (i.e., acidization) of petroleum reservoirs is the process of injecting acids into a porous, low permeability, geologic formation in order to dissolve aluminosilicate minerals and thereby increase near-well bore permeability. The new knowledge developed in this dissertation is intended to forecast the mechanisms associated with zeolite dissolution processes and provide a basis for designing the acid stimulation of petroleum reservoirs. The objectives of this research are the following: (1) elucidate the dissolution kinetics of zeolites in hydrochloric acid by formulating a rate law model from first principles, (2) establish the influence of silicate precipitation on zeolite dissolution kinetics, (3) identify the underlying dissolution mechanisms and limitations, and (4) develop a universal understanding of zeolite dissolution by applying new knowledge to synthetic zeolites. Laboratory dissolution experiments are performed using a batch reactor apparatus in order to obtain experimental values of zeolite dissolution rates. A surface reaction mechanism is examined and used to develop a fundamental rate law model for zeolite dissolution. Experiments undergird that silicate precipitates completely from solution during zeolite dissolution in hydrochloric acid, and that the precipitation does not influence the dissolution kinetics. Comparison of the measured initial silicon and aluminum dissolution rates demonstrates that aluminum atoms are selectively removed from zeolites. A selective removal rate parameter is defined as the ratio of the measured silicon dissolution rate to the stoichiometric silicon dissolution rate. A new concept is introduced of using a selective removal rate parameter to delineate the mechanism of zeolite dissolution by demonstrating the universal influence of the silicon to aluminum framework ratio. The mechanism comprises the removal of silicon facilitated by the selective removal of aluminum, leading to the formation of un-dissolvable silicate particles. General guidelines are set forth to predict the dissolution behavior of zeolites existing in reservoir formations.

The objective of this research is to improve the understanding of fluid transport through portland cement concretes and cement pastes under both unsaturated and saturated conditions. The sorptivity property is of primary interest for the unsaturated condition, and permeability and chloride ion penetration resistance (measured by rapid chloride permeability) are considered under saturated conditions. For unsaturated conditions, the key factors influencing sorptivity are water to cement ratio, degree of hydration, sample age, effective porosity, degree of sample saturation, sample drying temperature, and aggregate volume fraction. Porosity measurements from the water absorption test are in agreement with predictions by Powers and Brownyard's classical model when the sample moisture state is accounted for. Using statistical analysis, a four parameter multi-variate linear model that includes water to cement ratio, degree of hydration, degree of sample saturation, and aggregate volume fraction is proposed to predict sorptivity. The model allows the concrete designer to estimate sorptivity in concrete based on mix design, hydration level, and moisture state. Under saturated conditions, experimental permeability measurements are in rough agreement with existing microstructure-based models when using pore structure measurements made directly on concrete samples, with emphasis given to models by Dullien (a combination of the Hagen-Poiseuille and Darcy equations), Carman and Kozeny (a hydraulic radius model), and Katz and Thompson (a formation factor model). However, making microstructure measurements on concretes instead of cement pastes does not improve model accuracy. Permeability and rapid chloride permeability measurements for ordinary portland cement concretes are well correlated to compressive strength, and are significantly impacted by climate zone and distance from the exposed concrete surface. Rapid chloride permeability results are influenced by both the physical pore structure and the conductivity of the solution in the pores. Supplementary cementitious materials reduce calcium hydroxide content and in turn pore solution conductivity and rapid chloride permeability measurements. Changes in calcium hydroxide content are used to predict changes in the conductivity of the pore solution and deviations from the expected relation to porosity. This allows the concrete designer to forecast rapid chloride permeability based on water to cement ratio, hydration level, and chemical composition.

The architecture of cognition is widely acknowledged to be modular; different parts of the architecture are specialized for different functions. This dissertation addresses two questions about this modular organization. First, can experience lead to the development of new functional modules that are specialized for acquired cognitive functions? Second, if it can, how might it do so? I present two studies suggesting that experience can indeed lead to new functional modules and a third study investigating one potential mechanism. The first study supports the hypothesis of experience-dependent functional specialization at the behavioral level, by demonstrating that letter recognition is functionally dissociable from digit recognition. It is well known that letters are detected more efficiently in the context of digits than in the context of other letters, but some researchers have argued that this dissociation is an artifact that arises because letters are physically more similar to other letters than they are to digits. If so, one would expect this so-called alphanumeric category effect to remain relatively constant when the characters are inverted, because the inverted letters would still presumably be more similar to each other than to the inverted digits. I show that letters and digits that fail to show the category effect when inverted, nevertheless exhibit a robust effect when turned upright. This result falsifies the physical similarity hypothesis and suggests that letter recognition and digit recognition are indeed dissociable. This dissociation presumably must be experience-dependent, because the distinction between letters and digits is arbitrary and culturally defined. The second study presents evidence for experience-dependent functional specialization at the neural level, by demonstrating that typing, a learned skill typically acquired during adolescence, is neurally dissociable from matched visual and manual controls tasks. Using functional magnetic resonance imaging, I found areas in posterior parietal and dorsolateral prefrontal cortices that were selectively active for typing, but not for matched visual and motor tasks. This result suggests that an acquired cognitive motor skill can be subserved by specialized neural tissue. The third study tested a mechanistic hypothesis about how experience could lead to neural specialization for an acquired function. I tested the hypothesis that co-occurrence statistics in the environment interact with correlational learning mechanisms in the brain to produce neural segregation of learned skills. Using functional MRI, I compared patterns of brain activation before and after participants trained extensively with two sets of stimuli presented in spatiotemporal isolation from each other which, according to the co-occurrence hypothesis, should lead to neural segregation of the two sets. I failed to confirm this prediction. Together, these investigations suggest that experience can indeed lead to the development of new functional modules, both at the behavioral and the neural level, but they leave open the question of how it does so.

This dissertation developed a computational model that simulates key components of affect theory as described by psychologist Silvan S. Tomkins. Tomkins' model is unique in its ability to integrate the findings and perspective of multiple disciplines, including evolutionary, neurological, and psychophysiolocial approaches, as well as account for the full range of motivational phenomena. As a means of evaluating the explanatory promise of this model, two distinct affective/behavioral phenomena were selected for simulation purposes: reducer/augmenter and learned helplessness phenomena. At the opposite ends of the nature/nurture continuum, these phenomena have both been documented to occur reliably in a multitude of studies involving living subjects. As part of the research for this dissertation, artificial environments and experimental procedures analogous to those typically used for testing the key theoretical constructs involved with these phenomena were designed and implemented computationally. Using the simulated model, a series of experiments were conducted, and the output of the model was compared to the well-replicated findings in the relevant literature. Results of the reducer/augmenter simulation were generally consistent with the hypothesized findings, i.e., reducers tend to seek-out and prefer greater levels of sensation than augmenters. The results also suggest, however, that reducers and augmenters may actually have distinct behavioral profiles in terms of sensation-seeking and general activity levels that have not yet been explicitly addressed or fully appreciated. The experiments were also able to replicate well-known learned helplessness phenomena. These phenomena were only present, however, when the physiological effects of perceived efficacy were simulated and weighted relatively heavily. For this dissertation, efficacy was viewed as the system's confidence it its ability to attain a desirable outcome, and it was assumed that efficacy levels were inversely related to aggregate stimulation levels. The implications of these findings are addressed individually for each phenomenon, affect theory as a whole, theories of cognition and emotion in general, as well as for the development of autonomous adaptive agents. Suggestions and tools for future research in these areas are also provided.

An accurate model is needed for the flow of resin through fabric reinforcements, especially those that have been deformed, mainly in shear, when conforming to the shape of a curved part. The goal of this work was to develop such a model, based on the fabric microstructure. Experiments were carried out to determine the permeability of sheared fabric reinforcements. The trends observed could not be modeled by existing semi-empirical or empirical approaches. A three-dimensional fabric model was developed, as well as an algorithm to obtain cross-sections through fabric layers at any desired angle and through any desired point, for any shear angle. Those tools were used to interrogate the effect of layer nesting and to establish the geometry of the gaps that occur between fabric tows. After verifying that the assumptions for creeping flow were valid for cases of interest, a model based on gap size was developed. Results obtained with this variable-gap model for realistic production conditions bound the experimental permeability data, and give excellent predictions for the principal flow directions. Moreover, the techniques developed here use no fitting parameters.

For absorbed laser intensities of around 1010--10 12 W/m2, both melting and vaporization of the target workpiece occurs. Vaporization of the melt causes a pressure rise in the melt, a recoil pressure due to the momentum of the vaporizing molecules. Radial variations in the laser intensity lead to differing amounts of vaporization over the extent of the laser beam. Due to the differences in vaporization, pressure gradients are established in the melt, and these pressure gradients act to drive the melt away from the centerline and towards the edge of the beam where melt ejection occurs. Therefore, hole drilling is a result of both material vaporization and melt expulsion. Understanding the fundamental heat transfer and fluid flow phenomena in this drilling process is the key to linking the input laser characteristics with the resulting drilled hole. The focus of this work is the development and application of semi-analytic and numerical analysis techniques to the laser drilling process accounting for recoil-pressure-driven melt expulsion as a means of material removal. Stagnation flow, integral, and Fourier analysis techniques are applied to both pulsed and continuous wave laser operation with a variety of laser powers, beam radii, pulse lengths, pulse frequencies, and pulse shapes. Drilling trends are presented both in a qualitative and quantitative manner as functions of the operating characteristics of the laser. One of the significant advances of these analyses over previous research efforts is the treatment of the melt flow due to recoil pressure. The results of the analyses for several different materials show that only a small amount of the material is vaporized. Typically less than 20% is vaporized and the rest is removed via melt expulsion, removal mechanics that result in a more energy-efficient drilling process. It was determined that operating the laser in pulsed mode results in higher pressure gradients, faster drilling speeds, and thinner melt layers when compared with cw drilling for the same average power. When compared with experimental data from the literature, reasonably good agreement is observed.

In this thesis, we deal with the InGaAs/GaAs quantum dots and InGaN/GaN quantum systems. Both of the systems are under intensive study these days. Self-assembly growth of quantum dots on lattice mismatched substrate provides a promising way to realize zero-dimensional systems. The strain tensor in QDs is calculated and the spectrum via eight-band k· p is computed. Our results show several confined states in conduction band in agreement with experiments, while the simple single band method only has one bound state. The scattering mechanism in QDs are also studied. Thermalization through phonon processes is shown to be minimal, while electron-hole scattering is demonstrated to be an efficient way for carrier's thermalization within quantum dot. We also developed a set of equations for QD lasers. Within this framework, the threshold current density and multi-mode operation, as well as modulation of QD lasers are studied, which shows the general agreement with experiments. III-nitride materials have extensive applications in the area of optoelectronics which covers the blue light region, solar-blind detectors and high-power devices. The presence of strong piezoelectric field and spontaneous polarization, as well as large material inhomogeneity make III-nitride semiconductor have new properties comparing with conventional III-V materials. In this thesis, the important InGaN/GaN quantum wells are studied by including these new effects. Our study shows that the photoluminescence in InGaN/GaN quantum well originates mainly from the band-band transition, while exciton is not important. The large Stokes shift is due to the strong piezoelectric field and effective quantum well width fluctuations. We demonstrate the existence of the linear electro-optic effect in this system. Finally, gain spectrum is calculated in InGaN/GaN quantum well laser and compared with published experiments.

The research presented herein has focused on debinding of an ethylene copolymer from a SiC based molded ceramic green body. Examination of the binder burnout process was carried out by breaking down the process into two distinct regions: those events which occur before any weight loss begins, and those events occurring during binder removal. Below the temperature of observed binder loss (175$\sp\circ$C), both reversible and irreversible displacement was observed to occur. The displacement was accounted for by relaxation of molding stresses, thermal expansion of the system, and melting of the semicrystalline copolymer occurring during heating. Upon further heating the binder undergoes a two stage thermal degradation process. In the first stage, acetic acid is the only degradation product formed, as determined by GC/MS analysis. In this stage, component shrinkage persisted and it was found that one unit volume of shrinkage corresponded with one unit volume of binder removed, indicating that no porosity developed. The escaping acetic acid effluents must diffuse through liquid polymer filled porous regions to escape. The gas pressure of the acetic acid species produced in the first stage of the thermal degradation may exceed the ambient pressure promoting bubble formation. Controlling the heating rate of the specimen maintains the gas pressure below the bubbling threshold and minimizes the degradation time. Experiments have determined the kinetics of the reaction in the presence of the high surface area (10-15m$\sp2$/g) ceramic powder and then verified that acetic acid was diffusing through the polymer phase to the specimen surface where evaporation is taking place. The sorption method measured the diffusivity and activity of acetic acid within the filled ceramic system within a TGA. These data were incorporated into a Fickian type model which included the rate of generation of the diffusing species. The modeling process involved prediction of the bloating temperature as a function of the sample size for a given heating rate. The predicted results and experimental results show good correlation. The model was used to optimize the heating schedule which minimized the binder removal time.

The combined effects of periodicity-destroying irregularities and structural damping on the dynamics of multi-span beams are investigated. It is shown that both harmonic waves and normal modes of vibration that extend throughout the ordered, undamped beam become spatially attenuated if either small damping or small disorder is present in the system. The physical mechanism which causes this attenuation, however, is one of energy dissipation in the case of damping but one of energy confinement in the case of disorder. The confinement phenomena are studied over a wide frequency range for beams resting on simple supports and with variable interspan coupling. Approximations of the localization factor (the average rate of spatial exponential decay of the vibration amplitude) are derived by statistical perturbation methods and validated by Monte Carlo simulations. If the interspan coupling is strong, localization effects are weak and of no practical significance for most engineering structures. On the other hand, localization is severe for small interspan coupling. It is found that the effects of damping and disorder simply superpose for a multi-span beam with strong interspan coupling, but interact less trivially in the weak coupling case. The adequacy of the statistical analysis to predict accurately localization in finite disordered beams with boundary conditions is also examined. An experimental investigation of the effects of span length disorder on the dynamics of a twelve-span beam specimen is performed. Experimental results demonstrate that the transmission of vibration which takes place within the frequency passbands of the periodic beam is greatly hindered when span length randomness is introduced. The spatial localization of both the mode shapes and the steady-state harmonic response to an end excitation is observed. This study reports one of the first systematic experiments carried out to demonstrate the occurrence of vibration localization in nearly periodic structures. The dynamics of ordered and disordered multi-span beams on flexible supports are also investigated. This multi-coupled structure is characterized by two pairs of waves. While for the ordered infinite structure there exist frequency passbands for which the free harmonic waves propagate without attenuation, the introduction of disorder results in a wave localization to a few of the spans and an energy conversion from one type of wave to the other. It is shown that the spatial decay of each wave type is governed by an exponential envelope. These exponential decay constants define a measure of localization and are found to be equal to the Lyapunov exponents of the product of the random wave transfer matrices of the spans.

Experimental study, dimensional analysis and computational analysis are conducted on air-oil two-phase flows in a prototype of power transmission lines in axial rotation. Oil is supplied into the lubricating system through one radial inlet duct, one hollow shaft, and one or two radial exit branches open to atmosphere. The branch-to-shaft diameter ratio, inlet oil flow rate, and rotational speed are varied. In the experimental study, test sections are made transparent so as to observe the two-phase rotating flow patterns and measure the interfacial diameter in the shaft. Changes in time-average inlet pressure and exit oil flow rates are measured as functions of rotational speed for both spin-up and spin-down processes. Transitions of flow patterns in the shaft under the quasi-steady condition are plotted. It is disclosed that cavitation in the oil flow is induced by the intrusion of outside air into the shaft through the branch, featuring a high hydraulic head loss, against the exit oil flow. Hysteresis phenomena are also revealed for variations of oil flow rates, inlet pressure and flow patterns, and are due to the gaseous component contributing a nonlinear spring constant to the rotating system. In the dimensional analysis, the air core diameter in the shaft is measured and correlated, and the void fraction is well predicted. Both plots of Reynolds number of oil film versus rotational Reynolds number and void fraction versus Rossby number show the possibility of dryout, the avoidance of which is critical to the lubrication of rotary devices. Heat transfer and evaporation that worsen the dryout are briefly discussed. In the computational analysis, both the governing equations and empirical equations for hydraulic head losses and piping junctions are applied. Exit oil flow rates through identical twin branches are calculated for each two-phase flow regime, and the predicted results in the single-phase and annular flow regimes closely agree with the experimental data. The present study can be applied to select proper lubricants or coolants and improve lubrication performance of rotating machinery such as automatic transmissions, power generators and gas turbines.

Film cooling effects have always been crucial for the engine/rocket/ramjet propulsion systems. Knowing the pressure and temperature distribution of the flow is very important for both system and structural analyses to find optimal design. An efficient time dependent, compressible Navier-Stokes solver using higher order accuracy algorithms employing the finite-volume method is developed for this work. The physics inside the flow field with a cooler secondary mass stream injected into the channel is studied. The results showed that for subsonic main flow, the injected mass stream will bend and accelerate in the downstream direction, and creating a region of lower temperature near the downstream walls. This lower temperature region also exists even if there is a heat flux added to the flow system. Therefore, film cooling effect exists for the subsonic flow. For supersonic flow, however, the injected mass flow, instead of bending toward the downstream wall in order to have a cooling effect, is bent toward upstream direction and retards the main flow, resulting in a stagnant flow region. The temperature in the entire flow field is found to increase an appreciable amount even though the temperature in the stagnant region is found to be relatively lower than other areas. Therefore, there is no film cooling effect observed for supersonic flow. These phenomena have been verified by the experimental work. For subsonic flow, the acoustical wave is found to travel forwards and backwards in the field system while the pressure gradient is favorable for the whole flow field. For supersonic flow, there is always an adverse pressure gradient region formed near the walls upstream of the mass-injection location. Inside this adverse pressure gradient region, an air bubble is usually found to exist. The flow interactions between the main stream and secondary stream increase the flow vorticity. This vorticity is found to travel in the downstream direction for subsonic flow. However, for supersonic flow, this vorticity is found to travel in both the upstream and the downstream directions.

This study explores the potential relationship between extended family phenomena and mental health status. Its central question is: what is the effect of a cohesive integrated extended family network on a person's mental health status? The pilot study of the National Chicano Study on Identity and Mental Health (supported by Grant No. MN30244 of the Center for Minority Group Mental Health Programs of the National Institue of Mental Health) served as the source of the survey data for this study. The data are based on a sample of 81 Mexican-origin households representative of two census tracts comprising the Mexican community in Detroit, Michigan, which has the second largest metropolitan concentration of people of Mexican descent in the Midwest. The model developed for examining a relationship between extended family and mental health status posits a direct relationship between geographical extendedness (a measure that combined both size and proximity of the extended family) and mental health status (as measured by two psychophysiological symptom scores--the anxiety score and the psychosomatic score, and one score that is more psychological in nature--the general mental health score). In addition, geographical extendedness is posited to influence mental health status indirectly through: (1) integratedness of the extended family as measured by frequency of visitation with the extended family and the extent of familistic value preferences; (2) ethnicity as measured by Mexican cultural behavior and associational behavior; and (3) provision of aid--personal services (non-mental health aid) and psychological support (family mental health aid). The findings of this study indicate that the larger and closer geographically the extended family is, the better a person's mental health status (i.e., the less likely a person will feel lonely, keep opinions to him/herself to avoid quarrels, and have worries affect him/her physically). This relationship between geographical extendedness and general mental health score was statistically significant when simple effect were measured, but not when age and education were controlled in a regression analysis. In the final analysis, the control variables of age and education had powerful influences on most of the major variables in the study model. For example, age had a particularly powerful influence on geographical extendedness such that younger adults in this sample tended to have more extended kin living in close proximity. The effects of education, compared to those of age, were more pervasive. The direct effects of education in the model indicated that the better educated in this sample, in addition to being younger, have more kin available, have a better mental health status, are less tied to Mexican cultural behavior, exchange more non-mental health aid, and tend to seek out less family mental health aid. The small size and homogeneous nature of the sample precluded being able to test the core relationship between the presence of extended family and mental health status among different age groups for possible interactions. A larger and more varied sample is clearly needed in order to examine this relationship among different age groups. Nevertheless, the findings of this study do suggest that the extended kin group is a factor of substantial importance in any consideration of mental health.

Objectives. The aim of the study is to explore the prediction of in vivo conditions through the use of in vitro and in situ models. To understand the mechanism of CsA's absorption in humans, in vivo intubation technique was used to measure the effective permeability (P$\sb{eff}$) of CsA, cephalexin and marker compounds. Methods. In vitro Caco-2, in situ rat perfusion and in vivo human permeability models were chosen to evaluate their implications. The effect of surfactant (e.g., Cremophor EL$\sp\circler$) to the measurement of permeability was assessed in Caco-2 and rat models. The intestinal P$\sb{eff}$ for CsA, cephalexin, and marker compounds was determined in the proximal jejunum of twelve healthy volunteers via in vivo single pass perfusion technique. The correlations between the P$\sb{eff}$ of CsA, marker compounds, P-glycoprotein (P-gp), and cytochrome P450IIIA4 (CYP3A4) were analyzed. Results. Permeability of a fixed concentration of CsA decreased with the increased concentration of surfactant to 0.2% in both Caco-2 and rat models. There was a linear regression between the wall permeability from the rat study and the P$\sb{eff}$ from the human study. Based on 1.75 cm intestinal radius and the mixing tank model, the mean ${\rm P}\sb{eff}\pm{\rm SE}$ of CsA, cephalexin, propranolol, phenylalanine and PEG 400 were $1.61\pm0.16\times10\sp{-4}$ cm/sec, $1.56\pm0.33\times10\sp{-4}$ cm/sec, $2.98\pm0.43\times10\sp{-4}$ cm/sec, $4.66\pm0.87\times10\sp{-4}$ cm/sec, and $0.79\pm0.12\times10\sp{-4}$ cm/sec, respectively. Conclusions. In vitro Caco-2 model reflected the effect of surfactant in the in situ rat model. Linear regression between the permeability measured in the rats and that in humans implies that in situ rat model was suitable to predict what happened in humans. Based on the fraction of dose absorption versus human permeability plot, CsA is a high absorption drug. Through Forward Multiple Regression, it was revealed that 41% of CsA's permeability variation was accounted by the permeability variation of propranolol. Neither intestinal P-gp concentration nor CYP3A4 contributed to CsA's permeability variation. The lack of correlation between P-gp and permeability of CsA may be due to (1) offset of intestinal P-gp function by 0.2% Cremophor EL or (2) decreased permeability of CsA with mixed micelles formation and reduced thermodynamic activity of CsA or (3) both factors.

In this investigation order-disorder phenomena and related structure-property relationships have been investigated by means of $\rm\sp{57}Fe$ Mossbauer spectroscopy on four natural metal oxides: galaxite, $\rm MnAl\sb2O\sb4;$ franklinite, $\rm ZnFe\sb2O\sb4;$ iwakiite, $\rm Mn\sb{1.1}Fe\sb{1.9}O\sb4,$ and ilvaite, $\rm CaFe\sb3Si\sb2O\sb8O(OH).$ These Mossbauer spectroscopic studies have been complemented by the following characterization and property measurement techniques: electron microprobe analysis, magnetic susceptibility and x-ray diffractometry. Galaxite from Bald Knob, North Carolina, has been found to contain $\rm Fe\sp{3+}$ ordered on the octahedral sites based on Mossbauer spectroscopic data, contrary to earlier studies reporting the presence of $\rm Fe\sp{2+}$ in galaxite. In the course of this investigation, it has also been discovered that a widely-advertised galaxite specimen from Bo Phloi, Thailand is, indeed, not galaxite but rather a lherzolite spinel. An unusual franklinite from Langban, Sweden, one of the first authenticated occurrences outside of Franklin, New Jersey, has been found to be very similar to stoichiometric zinc ferrite, having a high zinc content with exclusive ordering of $\rm Fe\sp{3+}$ on the octahedral site with no indication of $\rm Fe\sp{2+}.$ In addition, a magnetite phase, which is believed to be an exsolution product, also present in this franklinite specimen, was found to be similar to natural and synthetic magnetite on the basis of its Mossbauer parameters. There are indications of some foreign ions in solid solution but the purity level of the magnetite phase approximates that of high quality single phase magnetite single crystals. Clustering of manganese and iron in iwakiite has been confirmed by Mossbauer spectroscopic analysis of iwakiite samples heated at 1000 K far 17 and 77 hours. These heat treatments resulted in the formation of an iron rich phase $(\alpha$-hematite) and a disordered manganese rich phase. Investigations at 298 K of the electronic properties of ilvaite using Mossbauer spectroscopy have revealed a trend in the spectroscopic profiles with Mn content. Magnetic susceptibility measurements of ilvaite have indicated a negative correlation between manganese content and the magnetic ordering temperature of the $\rm Fe\sp{2+}$ M2 sites. The structure-property relationships in ilvaite have been found to be complex and no simple correlations have emerged from this investigation.

An investigation of the dynamics of periodic and nearly periodic disordered truss beams is presented. An exact wave transfer matrix methodology is chosen to describe the characteristic harmonic waves and the normal modes of vibration of these multi-coupled periodic structures. The method is found to capture accurately the dynamics of truss beams in wide frequency ranges, even at those higher frequencies where the individual truss members undergo resonance and where the modal density is high. The methodology is extended to examine the effects of slight disorder among the bays upon the propagation of waves and the transmission of vibration through the truss beam. However, the approach faces severe numerical problems for the disordered system when taking the product of random wave transfer matrices. In order to circumvent this difficulty, a new algorithm is developed to calculate accurately the wave amplitudes at all bays. It is shown that both free harmonic waves and modes of vibration that extend throughout the entire ordered structure may become localized to a few of the bays of the disordered truss beam. The concept of power flow is utilized as a scalar descriptor of localization to examine the interactions among the various waves present in the structure. Results show that leakage of energy occurs from the wave pair that is most subject to localization to wave pairs that are less prone to localization, suggesting that localization is more difficult to achieve in multi-coupled systems than in mono-coupled ones. The wave conversion mechanism observed here is a novel phenomenon that is characteristic of disorder effects in multi-coupled structures. Lyapunov exponents are applied to examine the asymptotic decay rates of waves in both mono- and multi-coupled systems. It is found that the decay rate of each wave tends to decrease from the largest Lyapunov exponent to the smallest one. When the wave conversion is significant, energy tends to transmit along the system according to the smallest Lyapunov exponent.

This thesis presents the results of a three year study devoted to discovering the life and phenomena found in Lake Worth near Fort Worth, Texas.