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In this Thesis a novel approach is followed to facilitate the experimental investigations on the flow pattern transitions from separated to dispersed flows using a cylindrical bluff body in horizontal oil-water flows. A transverse cylindrical rod is used as a bluff body which is placed under the interface of the two immiscible liquids and near the test section inlet to passively generate interfacial perturbations and breaking waves. This approach was inspired from the use of hydrofoils in ships that reduce frictional drag via increased air entrainment. Studies are carried out using two flow facilities and high speed imaging combined with laser based measurements are performed at two axial locations along the test section, immediately after the cylinder and at large distance away from the cylinder. The effect of a confined geometry on the characteristics of the von Karman vortices and on the general flow behaviour immediately downstream of the cylinder are investigated in single phase water flows. It is found that the 3D pipe geometry does not affect significantly the vortex shedding behind the cylinder at least in the central plane of the pipe. The frequencies of the vortex shedding were comparable to those from a cylinder in an unconfined liquid. The results from two phase flows reveal that the cylinder reduces the mixture velocity for the transition separated to dispersed flows. It also actuates interfacial waves that are found to be non-linear and convective. In many cases the waves have the same frequencies as the von Karman vortices depending on the submergence depth of the cylinder underneath the oil-water interface and on the Froude number of the water layer. The observations suggest that strongly non-linear waves are responsible for forming thin ligaments that eventually break up into droplets.

This work presents recent developments on brane tilings and their vacuum moduli spaces. Brane tilings are bipartite periodic graphs on the torus and represent 4d N = 1 supersymmetric worldvolume theories living on D3-branes probing Calabi-Yau 3-fold singularities. The graph and combinatorial properties of brane tilings make the set of supersymmetric quiver theories represented by them one of the largest and richest known so far. The aim of this work is to give a concise pedagogical introduction to brane tilings and a summary on recent exciting advancement on their classification, dualities and construction. At first, particular focus is given on counting distinct Abelian orbifolds of the form C3/[gamma]. The presented counting of Abelian orbifolds of C3 and in more general of CD gives a first insight on the rich combinatorial nature of brane tilings. Following the classification theme, the work proceeds with the identification of all brane tilings whose mesonic moduli spaces as toric Calabi-Yau 3-folds are represented by reflexive polygons. There are 16 of these special convex lattice polygons. It is shown that 30 brane tilings are associated with them. Some of these brane tilings are related by a correspondence known as toric duality. The classification of brane tilings with reflexive toric diagrams led to the discovery of a new correspondence between brane tilings which we call specular duality. The new correspondence identifies brane tilings with the same master space - the combined mesonic and baryonic moduli space. As a by-product, the new correspondence paves the way for constructing brane tilings which are not confined to the torus but are on Riemann surfaces with arbitrary genus. We give the first classification of genus 2 brane tilings, illustrate the corresponding supersymmetric quiver theories and analyse their vacuum moduli spaces.

This thesis describes a study of the synthesis and characterisation of a new family of cationic alkane-thiolate and -selenolate compounds bearing a phosphonium (or phosphine oxide) head group, and the applications as ligands for the stabilisation of gold nanoparticles. The ability of these cationic phosphonium gold nanoparticles as substrates for the detection of negatively charged biomolecules has also been explored. In chapter 1, topics concerning the synthesis of functionalised gold nanoparticles, their biorecognition properties, the application of these nanoparticles in the biomedical field and gold nanoparticles stabilised with phosphorus-containing ligands, are outlined in a literature review. Instrument details of the analytical methods employed to characterise all the compounds and nanoparticles obtained in the study are outlined in Chapter 2. The syntheses and structural characterisation by NMR, ESMS and X-ray crystallography of cationic phosphonium-containing ligands are described in Chapters 3 to 5. Chapter 3 contains the description of the synthesis of phosphonioalkylthiosulfate zwitterions. The synthesis of related phosphonioalkylselenide compounds is presented in Chapter 4, and Chapter 5 is concerned with the synthesis of phosphonioalkylthioacetate and related phosphine oxide ligands. In Chapter 6, the preparation of the cationic phosphonium-functionalised gold nanoparticles using the phosphonium-containing compounds as protecting ligands, in a two-phase liquid-liquid (DCM-H[2]O) and one phase (ethanol) systems, is described. This chapter also contains details of characterisation of these nanoparticles by NMR, XPS and TEM. The ability of the cationic phosphonium gold nanoparticles to interact with RNA and cDNA, and the potential of using these nanoparticles as biorecognition systems was investigated by the Biacore Surface Plasmon Resonance technique and this work is described in Chapter 7. Finally, a summary of conclusions and some suggestions for future work are presented in Chapter 8.

This study has the aim of examining the effects obtained mainly through the leadership development process through small group dynamics for the purpose of making the youth group church, vitalized. The church reached the conclusion that the important problem for continuous church development was how to find a trained leader and to help the leader perform ministry dynamically on the actual site of ministry. In other words, it has been strongly requested to train leaders to be able to strive for the ministry with a sense of pride and mission with dedicated minds as small group leaders. It has been natural to present an effective concept of leadership to make leaders grow as disciples with a sense of mission, to enable continuous and effective training through curriculum, and to establish the strategy for small groups to meet the above requests. Therefore, in the context of such necessities, the church should perform the following works. First, the church should make small group leaders grow with a strict sense of mission. Second, the church should establish a program to train the leaders to fit the characters of the church by systematizing substantial leader training course for the small group leaders to enable the dynamic activities of small groups. Third, the church should make the small groups a strong community of Jesus Christ to be able to perform dynamic mission, service, and other church functions as the most basic unit of the church through positive leadership training for small group leaders. With the above ideals, the church attempted the renewal of the church. To be able to reach such ideals, the church has performed the following activities. The church trained the leaders to understand the essence and the missionary mission of the church, as well as the ways of taking decisive action for the new spiritual challenge by making them understand the small group as a community. The church taught the leaders to make them realize the mission and devotion of small group leaders as the leaders demonstrating the sound leadership. The church taught the leaders about the importance of the participation of small groups as the model constructing the Kingdom of God ultimately and how the direction the church goes forward as the missionary community is related with the healthy development of small groups. The church attempted pastoral approaches with the awareness of the obstacles to the ways of progressing, evaluating, and re-establishing the works of the ministry of the church as the project for the revitalization of small groups to be able to manifest the training of the church leaders and to double leadership. The concrete program was presented and implemented to elevate the small group leaders as the fruit for effectively grafting the scientific approach on small group leadership. In other words, it was the Re-acts encounter training as the course for new believers, the basic doctrines class, the preliminary leaders school, the leaders school, the coaching school, the one-to-one disciple rearing course, and the prayer movement. The implementation of such ministries as the above has brought a great effect to the church community more than supposed with the concrete growth of leadership. And it has showed the importance of the growth of leadership based on the theory of ministry. There are several things that we could learn through the above program. We must remember the concerns and dedication on the leadership of the leader, and the concrete program on the training and rearing should be the key essences of the growth of the church. A substantial approach is more requested to make rearing and dedication of leaders and the maturity of the leadership appear as the concrete fruits of mission and service. We must establish a system of supporting devoted laypersons in leadership and rearing. We must pay attention to the fact that rich training and the basis of diverse programs of leadership are just the church theory. We have been able to really understand that the love of a true shepherd in leaders is necessary and most important, though we performed the training by establishing many diverse skills and professionalism and sometimes spirituality as the principal themes during the process of the leaders school. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://www.proquest.com/en-US/products/dissertations/individuals.shtml.]

Psychologically controlling and autonomy supportive parenting practices have been consistently shown to predict children’s academic and psychosocial functioning, yet the precursors of these behaviors remain relatively unclear. To shed light on the cognitive precedents of such parenting practices, the current study focused on parents’ child-based worth, a tendency for parents to base their self-esteem on their children’s accomplishments. Departing from a primary focus on child-based worth in the academic domain, the current study examined the role of mothers’ child-based worth across various domains of child development, including virtue, academic competence, and physical appearance. Furthermore, given the role of perceived pressure in intrusive parenting, the moderating roles of internal (e.g., prevention focus) and external pressure (e.g., perceived environmental threat) in the association between child-based worth and parenting behaviors were explored. In the current study, 302 mothers (Mage = 42.16, SDage = 8.54) of early to middle adolescents (ages from 10 to 17) recruited through Qualtrics Panel reported on their child-based worth, parenting practices, and additional pressure-related factors (e.g., regulatory focus, perceived environmental threat). Results showed that mothers based their self-worth on children’s academic competence to a greater extent than the virtue and physical appearance domains. Mothers who based their self-worth on children’s virtue and physical appearance tended to endorse higher levels of psychological control. In addition, child-based worth in physical appearance was associated with dampened autonomy support. Interaction analyses revealed that mothers’ characteristics related to internal pressure, such as prevention focus and emotion dysregulation, interacted with child-based worth dimensions in predicting psychological control. Little evidence was found to support hypotheses regarding the role of external pressure. Overall, the implications of child-based worth were larger and more consistent in predicting psychological control than autonomy support. Together, findings from this study augment our understanding of the roles of multiple domains of mothers’ child-based self-worth in parenting behaviors and how these associations may be modulated by other factors related to perceived pressure.

Presents new perspectives on Christian education in local churches in Korea towards the 21st century. History of Christian education and a description of the current status of Christian education in Korea; Analysis of pertinent topics and relevant issues; Implications on theology and studies of the bible.

Supplementary cementitious materials (SCMs) improve the long-term strength and durability of concrete systems through the pozzolanic and/or hydraulic reactions that form additional calcium silicate hydrate (C-S-H) phases. SCMs come in various shapes and forms, and ASTM C618 provides a standard specification that covers coal fly ash and raw or calcined natural pozzolans. However, the two main criteria outlined by the standard, sum of oxides and strength activity index (SAI), are not sufficient for indicating pozzolanicity of materials; and existing test methods for measuring reactivity or pozzolanicity are yet to be standardized. Due to these existing problems, the accelerated mortar bar test (AMBT) outlined by ASTM C1567 and modified SAI testing were implemented in tandem to assess pozzolanicity of materials. Known inert materials and pozzolanic materials that qualify as Class N pozzolans and Class F fly ash were tested per ASTM C1567 to find replacement levels that suppress ASR expansion below 0.10%. Then the same materials were tested at same replacement levels for modified SAI with a fixed water-to-cementitious materials ratio (w/cm) using cylindrical specimens. The data from the two test methods were compared and compiled to assess pozzolanicity. Materials that successfully suppressed ASR expansion below 0.10% and passed modified SAI testing over 75% of control were classified as pozzolanic materials. The proposed method of the thesis successfully screened inert materials that qualify as Class N pozzolans, and successfully identified pozzolanic materials.

This dissertation traces the history of a dietary reform movement, which sought “right eating” in early twentieth-century Japan. The movement revolved around the concept of shokuyō, which broadly referred to the art of nourishing life and vitality—yōjō—through proper eating. Its central proposition was a call for the return to “natural and traditional” foodways with a particular emphasis on the consumption of unpolished rice and largely plant-based foods. Chapter One explores how the movement and discourse of shokuyō came into being and developed as a reaction against modern transformations of Japanese society since the Meiji Restoration. It situates the shokuyō movement within the context of discourses on hygiene, health, and the overarching project of civilization and enlightenment. Although the late Meiji shokuyō advocates sought to associate its ideal diet within the boundaries of orderliness of nature and civil morality, the way to understand the relationship between food and health became increasingly overshadowed by the ascendance of institutionalized nutrition science in the 1920s. Chapter Two looks at how “efficiency” and “rationalization” became catchwords in food-related public campaigns and medical discourse in which the concept of shokuyō was superseded by that of eiyō (nutrition). In spite of this, the shokuyō movement, evolved toward another direction with a new critique of modern medicine. Chapter Three concerns this transformation by analyzing how Sakurazawa Yukikazu reconceptualized shokuyō theories as “Natural Medicine” by drawing on contemporary French critiques of biomedicine and Shinto ideology. The following two chapters trace the movement’s transformation in the 1930s from an esoteric and upper-class-centered one into a large-scale movement targeting wider sectors of society. Chapter Four looks at how the campaigners actively intervened in the wartime standardization of brown rice as the national staple in face of total war. Chapter Five on the other hand analyzes the shokuyō movement’s crusade against sugar consumption in Japanese migrants’ diets in Manchuria, showing how they attempted to bring together tenets of “eating right” and the project of Empire. This dissertation ultimately argues that shokuyō’s “traditionalist” and “natural” dietary persuasion fed into a cultural nationalist and imperialist political imagination grounded in a holistic understanding of the body, health, and environment.

From basic neuroscience evidence and theoretical explanation of the development of neuromotor skill, we know that the emergence of behavior is a self-organized process that results from the cooperative tendencies of multiple, heterogeneous subsystems within contextual demands. Via sufficient repeated cycles of perceiving and acting, many intrinsic and extrinsic resources are intertwined to produce new behavior patterns eventually becoming stable, functional skills. This means that through exploration and experience, underlying factors can be strengthened to foster the functional foundation for neuromotor and non-neural areas. This foundation leads to a proactive view on neuromotor rehabilitation for the development of functional motor skills in infants with neurologic problems: suggesting ways to optimize residual recourses, to increase functionality, to maximize neuromotor control, and to minimize the cascading effects on other systems. Therefore, multilayered reciprocal interactions among underlying factors should be studied during the emergence and control of behavior longitudinally for populations with neuromotor difficulties. The overall goal of this dissertation was to design empirical studies to identify changes in underlying subsystems in response to motor activity and to address how rigorous practice affects the development and recovery of neuromotor function in infants. With this series of studies, we examined changes in subsystems at multiple levels: At the neural level, we tested the integrity of spinal-level reflexes and concurrent functional skills. At the non-neural level, we determined behavioral adaptations to upright activity practice and the impact of practice on bone mineral content. Our results showed improvements in neuromotor and non-neural areas via massive repetitions of specific activities in infants with Myelomeningocele as well as with typical development. But, each subsystem showed its own unique rate of change in response to the massive activity. Gradual changes emerged first at the behavioral level such as walking skill changes with toddler or stepping pattern changes with Myelomeningocele infants, followed by non-neural levels, such as bone mineral content, and then slowly at the neural level such as integrity of sensorimotor loops. The study results will help researchers to design better, assertive early intervention protocols for infants who have neuromotor disabilities.

The time-dependent radiation transport has been solved using the spherical harmonics method. One problem with this method is that the scalar flux computed with the time-dependent spherical harmonics in 2D can become negative for rapid transients. In this dissertation, two schemes are suggested to overcome this problem. One relies on relaxing hyperbolicity of the spherical harmonics closure by using a quasi-static approximation and the other relies on removing linearity by making the equation nonlinear. A quasi-static approximation is normally made in theory to derive time-dependent diffusion theory, and this approximation maintains a positive flux. We have therefore explored such a quasi-static closure in in 2D to see if a positive flux can result. The resulting method is relatively accurate, producing better results than much higher order methods, even while having far fewer unknowns. However the numerical results show that the scalar flux can still go negative in a pulsed source problem in 2D and this method is still not robust. Next, using the eigenstructure of the variable Eddington factor equations to satisfy both the isotropic and beam-like limits we have derived a new Eddington factor as the simplest explicit polynomial of current-to-flux ratio. We have used the discontinuity structure and relaxation length as a way to compare the nonlinear Eddington factors. We have found that the existence of a minimum in the relaxation length implies the existence of discontinuity solution for nonlinear Eddingion closures. The numerical results show that our Nonlinear closure produces very similar results with Maximum Entropy closure in 1D and remains positive for rapid transients in 2D. This method therefore provides a robust method in 1 and 2D.

Poly(ethylene terephthalate) (PET), poly(trimethylene terephthalate) (PTT), poly(ethylene isophthalate) (PEI), and poly(trimethylene isophthalate) (PTI) were synthesized in a Parr reactor and melt-spun. Thermal and physical properties of the as-synthesized polymers and melt-spun fibers were determined. As-synthesized PEI and PTI were amorphous polymers and did not show any melting peaks by DSC analysis. All the polymers were thermally stable (TGA analysis). Amorphous films were made by a melt-press method with PET and PEI for determination of CO2 gas barrier properties. PEI, which has the meta-linkage of ester groups on the phenyl ring, had much lower CO2 gas permeability around one tenth that of PET, which has the para-linkage of ester groups on the phenyl ring. This is because in PET the phenyl rings are substituted in the para (1,4) positions, which allows for their facile flipping, effectively permitting gases to pass through. However, the meta-substituted phenyl rings in PEI do not permit such ring flipping, and thus PEI may be more suitable for barrier applications. The coalesced PEI was prepared from the inclusion compound of PEI with γ-cyclodextrin. The coalesced PEI may have retained partially highly extended and parallel chains from the narrow channels of the inclusion compound, resulting in better/tighter packing among the PEI chains and exhibited a higher glass-transition temperature. Cyclic oligoesters of PET, PTT, PEI, and PTI were prepared by cyclo-depolymerization of these polyesters. The cyclic oligoesters were mixtures of different sized cyclic oligomers. PET cyclic oligomers showed four melting peaks at 59, 122, 194, and 276 o C. The cyclic oligomers of PTT, PEI, and PTI showed single melting peaks at 241, 335o C and 147o C, respectively. The cyclic oligoesters could be converted to linear polyesters by ring-opening polymerization. PTT was also prepared by ring-opening polymerization of its cyclic dimer obtained as a by-product in the conventional manufacturing plant. Antimony, tin, and titanium catalysts were used with various concentrations. The highest molecular weight, 40,000 g/mol was obtained when 0.25 mol% of titanium(IV) butoxide was used.

This thesis addresses the relationship of students’ intuitive understanding of the limit of a sequence to their reversibility, which is an ability to reverse the order between epsilon and N as required in the rigorous definition of limit. The subjects of this research were students who had not had any experience with rigorous proofs using the rigorous definition of a limit. Eleven students completed a series of 1-hour semi-structured, task-based interviews once a week for 5 weeks. Monotone bounded, unbounded, constant, oscillating convergent, or oscillating divergent sequences were tested. Students represented each sequence numerically as well as graphically in determining convergence of the sequence. Students also used tools, called epsilon-strips, specially developed for this study to explore the reverse relation in defining limits through hands-on activities with the strips. Finally, students were presented the following epsilon-strip definitions, and were asked to evaluate the propriety of the definitions as statements of the limit of a sequence. epsilon-strip Definition A: A certain value L is a limit of a sequence when infinitely many points on the graph of the sequence are covered by any epsilon strip as long as the epsilon strip covers L. epsilon-strip Definition B: A certain value L is a limit of a sequence when only finitely many points on the graph of the sequence are NOT covered by any epsilon strip as long as the epsilon strip covers L. It was found that students’ understanding of the definition of the limit of a sequence was associated with not only their conception of limit but also their level of reversibility. In addition, there was improvement in students’ reversibility and/or their conception of limit through the epsilon-strip activity, even though there was no procedure for indicating students’ errors, correcting students’ misconceptions about limit, or confirming the propriety of the epsilon-strip definitions to students during the interviews. This study implies that the epsilon-strip activity, combined with the various types of sequences used in this teaching experiment, is one instructional method for helping students develop and accommodate their conception of the limit of a sequence.

The primary goal of this research is to examine how consumers respond when their freedom to choose is constrained due to product unavailability. Reactance theory would suggest that restricting individuals’ freedom of choice is likely to have an adverse effect, including lowered choice consistency caused by negative affect. The degree to which consumers will react adversely to product unavailability is likely to depend on how much freedom they expect prior to choice, and whether a choice constraint is perceived to be important to them. Managing consumers’ expectations and perceptions in this regard represents an important challenge facing retailers. When should consumers be notified of a choice constraint, and what actions can be taken to minimize any detrimental effects on consumer choice and satisfaction? Two studies examine the role of psychological reactance in explaining consumer reaction to product unavailability. The first study establishes the importance of the timing of notification regarding product unavailability. Preference for the unavailable product is shown to moderate the relationship between the timing of notification and choice of the most similar alternative. The second study further explores the role of psychological reactance by examining the process by which consumers restore their freedom and reduce negative affect associated with product unavailability through the selection of another product. The theoretical contribution of this dissertation is to show how the timing of notification influences consumer choice and satisfaction. Past research argued that the presence of an unavailable alternative would increase the choice share of its most similar alternative due to consumers’ cognitive biases, including loss aversion and similarity substitution. However, such cognitive accounts fail to fully explain why choice reverses when consumers are notified about product unavailability after they have made a choice. In addition, the existing accounts cannot rationalize why consumer preference impacts consumer reaction to product unavailability. Building on reactance theory, we offer a new motivational account that explains the role of both the timing of information and individual preference.

The electrical characteristics, including degradation, of high K (≅ 500) barium titanate based thick film capacitors were studied. It was found that a gold conductor made from Au metallo-organic paste is not compatible with the porous high K dielectric material. The leakage current of a thick film capacitor made from Ag/Pd thick film conducting paste and high K dielectric has shown ohmic and space charge limited current behavior with a 3/2 power voltage dependence. Voltage independence of thermal activation energy and time dependence of a leakage current have been observed. A healing effect by reversal of bias polarity and humidity effect on leakage current have also been studied. The 3/2 power voltage dependence can be attributed to point emission from surface indentations or clusters of Ag particles at the electrode. Two possible degradation mechanisms based either on simple vacancy movement or a reduced grain boundary potential barrier height are suggested. It has been found that an electronic conduction model based on reduced grain boundary barrier height is more reasonable than that of simple vacancy induced current model.

Electrical crosstalk is becoming increasingly important as size shrinks and component densities increase in hybrid circuits. This occurs especially in multilayer thick film circuits. Crosstalk studies at high frequencies apply transverse electromagnetic (TEM) or quasi-TEM mode. However, the TEM mode theory is not applicable at low frequencies and low frequency-crosstalk is still a concern for circuit designers. In this research, crosstalk equations were derived in a simpler way, which can be used for low frequency applications such as automotive electronics. Test patterns were designed in both single and multilayer substrates in order to study crosstalk parameters such as line separation, line width, ground distance, ground type, and multilayer thickness. The mutual inductance and the mutual capacitance were calculated in order to use them in predicting crosstalk for particular transmission line geometrical structures. A conventional technique was used for the mutual inductance, and a new conformal mapping technique was developed for the mutual capacitance. Frequency dependence of crosstalk was confirmed by the equations developed. There is good agreement between the experimental mutual inductance and mutual capacitance and the calculated values. Finally, crosstalk prediction ( simulated by combining crosstalk equations with calculated mutual parameters ) fits well with the measured values.