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Currently, transmission network security is treated within a deterministic and preventive control framework where network constraints and balancing costs are not fully optimised. This may be inefficient and lead to increased levels of congestion, potentially increasing cost of integration associated with low-carbon generation. In this context, this thesis assesses the effects of coordinating FACTS and HVDC transmission systems under both deterministic and probabilistic security frameworks and assuming an array of available preventive/corrective control actions. An deterministic/probabilistic cost-benefit model has been developed for assessing the economic and reliability performance of alternative control strategies enabled by coordination of flexible devices. Results demonstrate that probabilistic security for flexible AC/DC devices coordination is significantly more beneficial since it can lead to lower operating costs, increased infrastructure utilisation and improved reserve allocation across GB network. The framework is further developed to explicitly consider the likelihood of post-contingency events and wind uncertainty. A tight MILP representation, two novelty transmission losses penalty items and scenario reduction model are proposed to reduce computational burden in the large-scale system. Results demonstrate the advantages of probabilistic security to improving the overall efficiency of the system when integrate uncertain renewable generation. Adding flexible network technology could even increase system costs under a preventive security approach. Finally, a novel two-stage stochastic optimization model that incorporates effect of dynamic line rating (DLR) on transmission network operation with increased penetration of wind generation is proposed. The stochastic model co-optimizes energy and reserve holding levels for the forecasted/expected condition along with re-dispatch actions under real-time operation. The benefits of using DLR are demonstrated in terms of overall cost minimization, albeit reserve levels may be increased due to DLR uncertainty. Results also demonstrate that reserve services can be shared among multiple uncertainties. The impacts of forecast accuracy and reserve price on the performance of DLR is discussed.

Soft body armour is usually constructed by layering numerous layers of the same fabric. Such a construction, however, may not be the most efficient in providing the required protection due to different ballistic resistant efficiency of each layer. This research aims to optimise the construction of the panels for soft body armour by hybridisation in order to achieve the improvement of ballistic performance and reductions in weight. Twaron woven fabrics with different weave structures and Dyneema uni-directional (UD) laminates were used as components for the hybrid design of panels. Two complementary research approaches were employed in this study, namely the empirical method and the Finite Element (FE) analysis. The first part of this research systematically revealed the different ballistic characteristics of each layer in different positions of an armour panel and the way of energy absorption in the panel. The fabric layers in the front, middle and back of the panel exhibited different extent of transverse deformation and stress distribution. The energy absorption increases from front layer and reaches to the maximum value in the last perforated layer and then decreases gradually in the following back layers. Such pattern of energy absorption was not affected by either the striking velocity or the total number of layers in the panel, but the position, in the thickness, of the peak value in energy absorption was shifted more towards the back of the panel when the striking velocity increases. Such findings contribute to the understanding of different ballistic responses in different positions of an armour panel under ballistic impact. The second part of this research put forward a new hybrid design concept. According to above theoretical understandings of different ballistic characteristics in different positions of an armour panel, the fabric layers in the panel were discretely divided into three groups. In addition to the performance of different components for the panel and the influences of the laying sequence, a procedure for constructing hybrid armour panels has been established. The first group was composed of the first few layers on the striking face. The heavyweight fabrics as heat resistant layers were used in this group to resist the heat generated on the striking face. The second group contained some middle layers close to the last perforated layers. The lightweight fabric was combined in this group due to the higher energy absorption capacity. All back layers were classified into the third group. Dyneema UD laminates were placed in this group to constrain the large transverse deflection of the lightweight fabric and to minimize BFS of the panel. Two hybrid panels were designed and evaluated. In the perforation ballistic tests, the hybrid panel was more likely to stop the projectile compared to Twaron woven panels with the same areal density. In the non-perforation ballistic tests, the hybrid panel exhibited significantly lower BFS and achieved the reductions in weight. Such hybrid design makes best use of different available materials to achieve the improvement of ballistic performance and lightweight of a panel. It has a practical significance for the soft armour panel design.

In this thesis, we propose a new class of lattices based on polar codes, namely polar lattices. Polar lattices enjoy explicit construction and provable goodness for the additive white Gaussian noise (AWGN) channel, \textit{i.e.}, they are \emph{AWGN-good} lattices, in the sense that the error probability (for infinite lattice coding) vanishes for any fixed volume-to-noise ratio (VNR) greater than $2\pi e$. Our construction is based on the multilevel approach of Forney \textit{et al.}, where on each level we construct a capacity-achieving polar code. We show the component polar codes are naturally nested, thereby fulfilling the requirement of the multilevel lattice construction. We present a more precise analysis of the VNR of the resultant lattice, which is upper-bounded in terms of the flatness factor and the capacity losses of the component codes. The proposed polar lattices are efficiently decodable by using multi-stage decoding. Design examples are presented to demonstrate the superior performance of polar lattices. However, there is no infinite lattice coding in the practical applications. We need to apply the power constraint on the polar lattices which generates the polar lattice codes. We prove polar lattice codes can achieve the capacity $\frac{1}{2}\log(1+\SNR)$ of the power-constrained AWGN channel with a novel shaping scheme. The main idea is that by implementing the lattice Gaussian distribution over the AWGN-good polar lattices, the maximum error-free transmission rate of the resultant coding scheme can be arbitrarily close to the capacity $\frac{1}{2}\log(1+\SNR)$. The shaping technique is based on discrete lattice Gaussian distribution, which leads to a binary asymmetric channel at each level for the multilevel lattice codes. Then it is straightforward to employ multilevel asymmetric polar codes which is a combination of polar lossless source coding and polar channel coding. The construction of polar codes for an asymmetric channel can be converted to that for a related symmetric channel, and it turns out that this symmetric channel is equivalent to an minimum mean-square error (MMSE) scaled $\Lambda/\Lambda'$ channel in lattice coding in terms of polarization, which eventually simplifies our coding design. Finally, we investigate the application of polar lattices in physical layer security. Polar lattice codes are proved to be able to achieve the strong secrecy capacity of the Mod-$\Lambda$ AWGN wiretap channel. The Mod-$\Lambda$ assumption was due to the fact that a practical shaping scheme aiming to achieve the optimum shaping gain was missing. In this thesis, we use our shaping scheme and extend polar lattice coding to the Gaussian wiretap channel. By employing the polar coding technique for asymmetric channels, we manage to construct an AWGN-good lattice and a secrecy-good lattice with optimal shaping simultaneously. Then we prove the resultant wiretap coding scheme can achieve the strong secrecy capacity for the Gaussian wiretap channel.

To fully exploit the strengths of La2Zr2O7 pyroclores and promote them as a next-generation thermal barrier coating (TBC), the improvements of their thermally insulating property and fracture toughness are studied in this thesis. A strong phonon scattering source, rattlers, is found in Y3+-doped La2Zr2O7 pyrochlores. Rattlers dramatically flatten k (thermal conductivity)-T curves, or even make k approach the amorphous limit. The presence of rattlers is strongly dependent on (1) oversized atomic cages that are formed in pyrochlores; and (2) the occupation of smaller guest ions in those oversized cages. To maximize the rattling effect, In3+/Sc3+ ions that are much smaller than Y3+ are introduced to the La2Zr2O7 lattice. As envisaged, the smaller ions in the oversized lattice voids make k glass-like at a much lower doping content. Nevertheless, they are still not effective in reducing the high temperature plateau kmin. Instead, oxygen vacancies are very effective in reducing kmin, because they generate an electrostatic repulsion force among cations surrounding them, resulting in stronger lattice anharmonicity and weaker bonds. The plateau kmin is reduced dramatically by the filling of the B-sites in La2Zr2O7 with a 21% larger (and 50% heavier) Ce4+ guest ion rather than a 96% heavier (but similar-sized) Hf4+ ion, suggesting that a large absolute size of substitutional atoms is more effective in reducing kmin than a heavy absolute mass. This is because: (1) kmin is proportional to (E/M)0.5 (where E is the elastic modulus and M is the average atomic mass); (2) a larger size of guest ions tends to produce a weaker ionic bond and consequently, a lower E; and (3) the changing extent of E by introducing larger guest ions is much greater than that of M induced by adding heavier ones. Lastly, the fracture toughness (KIc) has been increased by dispersing the tetragonal 3 mol% Y2O3-stabilized zirconia (t-3YSZ) particulates in the La2Zr2O7 (LZ) matrix. The tendency of the dispersive t-3YSZ second phases transforming to monoclinic (m) phases strongly depends on the volume fraction introduced. For samples made from equilibrium route, they are toughened by phase transformations within the dispersive t-3YSZ second phases and a crack shielding effect arising from the residual compressive stress within the LZ matrix. An anticipated increase of KIc from ferroelastic toughening together with the residual compressive stress toughening highlights a potential to improve coating durability by depositing t’-3YSZ/LZ composite TBCs by the non-equilibrium route.

With increasing concern on the dwindling of the fossil fuel reserve and climate change, more and more effort has been focused on seeking green fuel to replace fossil fuel and mitigating the emissions of greenhouse gas (GHG). Biodiesel has attracted much attention for its sustainability, lower emissions of HC, PM and CO, and the diverse feedstock. In this study, diesel/diesel-like fuels were experimentally studied in terms of spray and combustion characteristics.

This study examines the effectiveness of traditional admissions criteria, including prior GPA, SAT, GRE, and TOEFL in predicting undergraduate and graduate academic success for American and international students at a large public university in the southwestern United States. Included are the admissions and enrollment data for 25,017 undergraduate American, 509 undergraduate international, 5,421 graduate American, and 1,733 graduate international students enrolled between 2005 to 2009. Person product-moment correlation, multiple regression, and user-determined stepwise regression were applied to the data. Results show high school GPA is the most predictive of first-year college GPA for both undergraduate American and international students. SAT has a medium correlation with first-year college GPA for American students and a large correlation for international students. High school GPA and SAT together explain one fourth of the variance in first-year college GPA for American students and over one half of the variance for international students. TOEFL has a medium correlation with first-year GPA for undergraduate international students but is not a significant predictor of first-year GPA when SAT is included in multiple regression. Unlike the results for undergraduate students, the traditional admissions criteria (undergraduate GPA and GRE) for graduate admissions explain a small portion of variance in first-year graduate GPA. Undergraduate GPA, GRE Verbal, and Quantitative together explain 6.3% of variance in first-year graduate GPA for American students and 3.1% for international students. The GRE Subject Tests are the best predictor of first-year graduate GPA for students who had taken the GRE Subject Tests. TOEFL has a small correlation with first-year graduate GPA for international students, and it is not a significant predictor of graduate GPA when GRE-Verbal is included. These findings have implications for undergraduate and graduate admissions, standardized admissions tests, university curriculum, and students' academic success. [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.]

Abstract: The social interactions that we engage in with those around us are crucial to our successful navigation of daily life, and the presence of others can largely influence our attentional allocation. However, less is known regarding social presence and interactions as they occur online; as the recent pandemic has led to a shift to online virtual social gatherings, it is even more imperative for us to understand the ways in which this can affect our attention. Here, we sought to understand whether implied social interaction and implied social presence can affect attention in a virtual visual search task. Implied social interaction was operationalized by telling participants they were cooperating and competing with a partner, while implied social presence was operationalized by the visual depiction of the other player on screen. To solidify our manipulation of implied social interaction, feedback was provided in the form of telling participants whether they were accurate or not, and their relative speed compared to the previous pair (cooperation) or compared to the opponent (competition). Our results indicate that, in line with prior work, participants who were told they were competing were significantly faster but less accurate than those who were told they were cooperating, suggesting that it is feasible to study implied social interactions using a virtual format. Although we did not find a significant interaction between this effect and our social presence manipulation, when comparing social presence to a baseline condition with no partner evoked, we found that participants prioritized accuracy when told they were cooperating and speed when told they were competing as compared to individual search. These findings suggest that the threshold to imply social presence may be lower than we thought, and that our cognitions regarding our social interactions can play a large role in affecting our attention.

This dissertation outlines the history of the symbiosis between painting and Du Fu’s poetry from the poet’s time to the twentieth century. Examining the combination of the two arts between 1912 and 1966 will show artists’ various ways of incorporating Du Fu’s poems in their paintings. It suggests that a shift of spectatorship from private circles of the educated elite to the common people and the Chinese Communist Party (CCP) took place around 1949, which fundamentally changed the functions of traditionalist art from private communication to service to the masses and the country. In the People’s Republic of China (PRC, 1949 onwards) the establishment of the Du Fu Memorial Museum in 1955 marked an important moment in the processes of politicizing and institutionalizing the symbiosis of painting and Du Fu’s poetry. The museum has directed and controlled the production, exhibition, and circulation of paintings after Du Fu’s poems based on constantly changing political realities. In this context, I argue in this dissertation that artists used their agency and incorporated Du Fu’s poetry in their paintings in ingenious ways. They transformed their paintings, with Du Fu’s texts, into versatile spaces, where on the surface they might appear satisfactory to the censors, but at other levels suggested alternative meanings available to elite viewers.

This dissertation is composed of three essays related to financial institutions and financial stability. The first essay constructs a measure of integration among global banks and examines its impact on bank insolvencies and bank crises. The second essay examines a special funding source, brokered deposits, from its history, regulation, types, and usage. The third essay investigates the concentration of payday lenders in a given county correlates to its regulatory environment, financial and demographic variables. Moreover, it examines the level of crime in a given county and assesses its relation to the presence of payday lenders.

This thesis is on molecular dynamics studies of drying suspensions of bidisperse nanoparticle mixtures. I first use an explicit solvent model to investigate how the structure of the dry film depends on the evaporation rate of the solvent and the initial volume fractions of the nanoparticles. My simulation results show that the particle mixtures stratify according to their sizes when the suspensions are quickly dried, consistent with the prediction of recent theories. I further show that stratification can be controlled using thermophoresis induced by a thermal gradient imposed on the drying suspension. To model larger systems on longer time scales, I explore implicit solvent models of drying particle suspensions in which the solvent is treated as a uniform viscous background and the liquid-vapor interface is replaced by a potential barrier that confines all the solutes in the solution. Drying is then modeled as a process in which the location of the confining potential is moved. In order to clarify the physical foundation of this moving interface method, I analyze the meniscus on the outside of a circular cylinder and apply the results to understand the capillary force experienced by a spherical particle at a liquid-vapor interface. My analyses show that the capillary force is approximately linear with the displacement of the particle from its equilibrium location at the interface. An analytical expression is derived for the corresponding spring constant that depends on the surface tension and lateral span of the interface and the particle radius. I further show that with a careful mapping, both explicit and implicit solvent models yield similar stratification behavior for drying suspensions of bidisperse particles. Finally, I apply the moving interface method based on an implicit solvent to study the drying of various soft matter solutions, including a solution film of a mixture of polymers and nanoparticles, a suspension droplet of bidisperse nanoparticles, a solution droplet of a polymer blend, and a solution droplet of diblock copolymers.

The number of implantable medical devices ranging from dental implants to cardiovascular implants has been exponentially increased in the last decades and various materials including metallic materials and polymeric materials are used in medical device manufacturing. In metallic materials, nitinol is widely used due to its superelasticity and well-known biocompatibility. Finite element modeling (FEM) along with in vitro and in vivo is being adopted to evaluate the medical device performance in patients and optimize medical designs. In this dissertation, four innovative implantable medical devices were developed and their performances were evaluated using finite element modeling and in vitro testing: 1) ventriculoamniotic shunt for aqueductal stenosis treatment. It has the conduit to drain excessive cerebrospinal fluid (CSF) to lower intracranial pressure in fetal brains and the anchors to prevent the device dislocation during the treatment. The shunt tube design was optimized using computational fluid dynamics calculations. The anchor design was determined with ANSYS Static Structural and the prototype was manufactured based on modeling results. In vitro pressure and flow rate measurement within shunt device demonstrate that the pressure in fetal brain can be reduced by 95.2% while the pressure elevation in amniotic sac is negligible. 2) TFN flow-diverter integrated with flow sensing system for cerebral aneurysm post-treatment monitoring. The flexibility of TFN membrane was investigated using both computational modeling and stretching experiment. As the TFN was wrapped on a flow-diverter backbone with junction points, we evaluated the attachment patterns between a TFN and stent backbone. Finally, micro-scale flow sensor was designed and fabricated based on the computational modeling. 3) compartmentalized stent to isolate the perfusion of the abdominal organs. The fluid dynamics inside the arterial and venous organ perfusion stent (OPS) was analyzed in terms of velocity distribution and wall shear stress (WSS). In vitro pressure difference both in arterial and venous OPS showed that the stent deployment with perfusion flow to the abdominal organs will not generate a significant load on the donor's heart. 4) retrievable stent graft for noncompressible hemorrhage control. The mechanical and biological properties of ePTFE membrane were investigated and the nitinol framed backbone was evaluated in terms of radial force.

Over the past three decades, the number of people employed directly in artisanal and small-scale mining (ASM) - low-tech, labour-intensive mineral extraction and processing - has increased from an estimated six to 44.7 million. On the back of buoyant gold prices, ASM activities have burgeoned worldwide, as has capital-intensive gold exploration and extraction. Growth of the latter is attributed to rises in foreign investment, specifically, work undertaken by a number of governments to lure multinational companies to their shores to prospect for gold, with the goal of developing profitable large-scale operations. But whilst generating significant revenue for host governments, this strategy has also brought ASM parties and the management of international companies together. The resulting interactions and engagements could, in some instances, be described as amicable and tolerating but in other cases, have culminated in violence. In sub-Saharan Africa, the concurrent expansion of both the large-scale mining and ASM frontiers has presented formidable governance and development challenges. Whilst most national governments in the region have prioritised the expansion of large-scale mining activities, at the same time they have struggled to come to grips with (or choose to ignore) why informal ASM activities have also expanded. Nor have they committed to managing the impacts of this growth appropriately and most importantly, to properly harness the potential benefits provided by the sector. At the same time, the academic literature has rather examined large-scale mining and ASM in relative isolation, shedding very little light on the factors which undermine efforts to broker and ultimately, maintain, cordial relations between those operating in both branches of the sector. The purpose of this thesis, therefore, is to broaden our understanding of this phenomenon through a case study of Côte d'Ivoire, an emerging gold mining frontier in sub-Saharan Africa. Through a multi-sited ethnography and archival research, I examine holistically how and why over time and across different spaces the relationships between different operators found in Côte d'Ivoire's gold mining interface have changed. My research has revealed how in the gold mining frontier of Côte d'Ivoire, where the boundaries between formal and informal, statutory and customary, local and global, and public and private can be extremely fuzzy, gatekeepers increasingly play a crucial role in facilitating mine operators' access to, and control of, mineral deposits. Here, the right to property and the ability to access mineral deposits are determined by a web of actors who constantly renegotiate their power and legitimacy. Focussing on a reconstruction of the history of mining during the colonisation, the role of a national government and the lifecycle of a mine, I demonstrate how analysing the entanglements of different conjunctural elements over time and across space allows for a more nuanced understanding of the dynamics of the (mining) interface. Whereas some factors that shape the mining interface can be observed at a single moment in a single place (e.g. a fatal mining accident), others can only be understood through a longitudinal lens (e.g. the impact of colonialism) or by focusing on developments at the (inter)national level (e.g. the adopted approach to mineral governance). I argue how a holistic examination of the mining interface allows to plot these elements along an axis of time and space. This enables to visualise the shortcomings of existing policy recommendations, which can go a long way toward diffusing and preventing tensions between mine operators. This offers a blueprint for policy makers to design and implement more inclusive and sustainable policy frameworks to facilitate peaceful intersectoral mining relations.

Understanding the surface/interface electrostatic properties of organic semiconductors has great implications for the fundamental transport properties of these materials and their performance in devices. Therefore, this thesis aims to correlate electrostatic properties with microstructure and mechanical strain in benchmark organic semiconductors. To this end, a number of scanning probe microscopy (SPM) techniques are employed to examine thin films and single crystals of prototypical organic semiconductors. In particular, strong variations of interfacial polarization at the organic/insulator interfaces are quantified by scanning Kelvin probe microscopy (SKPM). The roles of the dielectric type and deposition condition are identified. Moreover, striking lateral electrostatic heterogeneities are visualized in thermally deposited organic semiconductor bi-layers on various dielectrics, and are directly related to the complex microstructural motifs of the films. The mixed homoepitaxial growth modes, which give rise to the inhomogeneous microstructure, can be conveniently determined by combining two variants of lateral force microscopy (LFM), namely, friction force microscopy (FFM) and transverse shear force microscopy (TSM). Furthermore, a fundamental correlation is established between the surface electrostatic potential and mechanical strain. The effects of tensile and compressive strains in both elastic and plastic regimes are determined for the first time. Overall, organic semiconductors exhibit complex surface/interface electrostatic properties, which can be visualized by SPM and can be correlated with microstructure and mechanical properties.

Abstract: A key enzyme in maintaining sulfide homeostasis is the membrane-associated flavoenzyme sulfide:quinone oxidoreductase (SQR) found in nearly all domains of life (except plants). SQR maintains a critical equilibrium between sulfide (H2S, HS- and S2-) and elemental sulfur (S0), coupling the oxidation of sulfide to the reduction of ubiquinone via a non-covalent FAD cofactor. SQR interacts with the membrane via two amphipathic helices and the Q-pool through a conserved hydrophobic domain. The active site of SQR includes three cysteines (Cys160, Cys356 and Cys128) and the FAD in close juxtaposition to the ubiquinone binding site. To understand the sulfide oxidation mechanism, we expressed the wild-type sqr gene from Acidithiobacillus ferrooxidans, as well as several variants of conserved, catalytically important amino acids in E. coli BL21(DE3) and purified soluble, active, His-tagged SQR. The purified wild-type SQR and the variants were subjected to extensive kinetic (pre-steady state and steady state) and structural analysis (X-ray crystallography). We also monitored SQR activity in vivo by detecting the H2S produced by growing E. coli transformed with wild-type and variant SQR. Our catalytic activity analysis and structural determination led us to propose two alternative mechanisms: (1) A nucleophilic attack mechanism that involves Cys356–S–S− as a nucleophile which attacks the C4A atom of FAD; or (2) A radical mechanism of direct electron transfer from Cys356 disulfide to FAD. The growing polysulfide is held between Cys160 and Cys356. The role of Cys128 (most likely in the form of a disulfide) is confined to the release of the polysulfur product. We further investigated the role of the FAD and the conserved Cys and His residues using a combination of kinetics and EPR spectroscopy. Using steady state kinetics of Na2S-dependent decylubiquinone (DUQ) reduction we measured a kcat of 6.5 s-1 and a Km (Na2S) of 3.0 M and a Km (DUQ) of 3.4 M. Variants of Cys160, Cys356 and His198 had greatly diminished DUQ reduction activity whereas variants of Cys128 and His132 were less affected. A neutral flavin semiquinone was observed in the EPR spectrum of SQR reduced with Na2S which was enhanced in the Cys160Ala variant suggesting the presence of a Cys356-Sγ-S-C4A-FAD adduct. Potentiometric titrations of the FAD semiquinone revealed an midpoint potential (Em) of -139 ± 4 mV at pH 7.0 in wild-type SQR. The Em of the FAD in SQRCys160Ala (Em= -135 ± 5 mV) is similar to that in wild-type SQR. We also combined computational docking and kinetic approaches to analyze quinone binding. SQR can reduce both benzoquinones and naphthoquinones. The alkyl side chain of ubiquinone derivatives enhances binding to SQR but limits the enzyme turnover. Pentachlorophenol and 2-n-heptyl-4-hydroxyquinoline-N-oxide are potent inhibitors of SQR with apparent inhibition constants (Ki) of 0.46 µM and 0.58 µM, respectively. The highly conserved amino acids surrounding the quinone binding site play an important role in quinone reduction. The phenyl sidechains of Phe357 and Phe391 sandwich the benzoquinone head group and are critical for quinone binding. Importantly, conserved amino acids that define the ubiquinone-binding site also play an important role in flavin reduction.

Magneto-electro-elastic materials can convert energies from one form to the other among the mechanical, electric and magnetic ones, and thus they have potential applications in clean energy harvest, various sensors, actuators and other hi-tech areas. Analytical solutions are of great importance to analyze behaviors of magneto-electro-elastic materials, especially for magneto-electro-elastic bi-materials whose interface could substantially influence behaviors of the whole material. The extended Stroh formalism and Fourier transformation are adopted to derive the fundamental solutions in a three-dimesional magneto-electro-elastic bi-material. The solutions are in a line integral form. Responses on the interface are investigated. In terms of geometric domains, the obtained analytical solutions can be reduced to the ones in half space and homogeneous full space. In terms of material properties, the obtained solutions can be reduced to the ones in decoupled cases such as piezoelectric, piezomagnetic or elastic materials. Interfacial cracks with impermeable conditions on crack faces in three-dimensional magneto-electro-elastic as well as two-dimensional piezoelectric bi-materials are investigated. A numerical scheme based on the Crouch-type fundamental solutions and the extended displacement-discontinuity method is defined for analyzing interfacial cracks. The physically unreal oscillating singularity at the interfacial crack tip or front is avoided by replacing the delta expression with the distribution function in the solutions. The influence of this replacement and the effect of the Gaussian parameter on predicting fracture parameters are examined numerically. Electric and magnetic nonlinearities at interfacial crack fronts in a magneto-electro-elastic bi-material are considered by adopting the electric-magnetic polarization saturation model. In this model, the perfect electric displacement and magnetic induction saturations are assumed. Green’s functions for the ring element of uniform extended displacement discontinuities are derived to form the system of equations in the extended displacement discontinuity method. The unknown sizes of the electric and magnetic saturation zones are determined by the vanishing of the electric displacement and magnetic induction intensity factors at corresponding crack fronts. An iteration approach is designed to solve for the two unknown sizes. The effect of the electric/magnetic field on the saturation zones as well as the influence of the saturation zones on the stress intensity factor is discussed.

Abstract: I advance a theory of how institutional complexity of national systems shapes the fate of hybrid organizations. In particular, I investigate how various prevailing societal logics independently and jointly affect the founding and social mission focus of microfinance organizations (MFOs); a form of hybrid organization distinguished by lending to poor people, particularly women. Although the fate of organizational forms and practices is generally linked to that of the cultural frames that support them, I show that logics may act and interact in various ways to shape these outcomes. Drawing on neoliberal economics and gender inequality studies, I identify two logics, market and patriarchy, that are theoretically relevant to microfinance, globally prevalent, and variously influential across countries. I hypothesize and test (1) how market and patriarchy logics independently and interactively shape microfinance founding and the lending focus on women; (2) how the financial performance of an MFO affects its social mission fulfillment and how this effect is contingent upon heterogeneous configurations of market and patriarchy logics across nations; and (3) how the two logics shape capital flows into microfinance. Empirical analyses of these questions are based on a sample of MFOs in 111 developing countries between 1995 and 2007 and data on the funding structure of MFOs between 2007 and 2010. In addition to showing how hybrid organizations in general are affected by institutional complexity, the findings have practical implications for microfinance, where prominent groups promote market logic as a means to grow the sector and expand its outreach.

This dissertation addresses modern Chinese ink painters’ use of seventeenth-century yimin art as a philosophical, aesthetic, and political vehicle for synchronizing the fundamental values of Chinese art with the modern world during the first half of the twentieth century. In this case, the polemical term “yimin” designates “leftover subjects” or loyalists to a previous fallen dynasty. “Ming yimin art” refers to the ink paintings done by a group of seventeenth-century individualist masters—among whom the most famous is Shitao (1642-1707)—whose paintings often appear expressive or abstract from a modern perspective. The rediscovery of this individualist art in a modern context was carried out almost simultaneously in China and Japan, and later spread to Europe and America. Employing a body of still understudied materials from art journals, museum archives, and artists’ writings to paintings, my study challenges the common misconception that early twentieth-century Chinese ink painters were conservative and their paintings outdated. I argue modern ink painters re-appropriated and canonized seventeenth-century individualist painting with a dual purpose not only to legitimize and prioritize the value of traditional ink aesthetics within an international art scene, but also to create an ink painting suitable to a new forward-looking Chinese culture.The rediscovery and reformulation of Ming yimin painting by twentieth-century intellectuals can best be understood as a process of temporal and spatial “alignment” or “synchronization” as modern ink painters sought to situate themselves both within China’s historical continuum and within an international scene increasingly aware of cross-cultural comparison and market competition. This bipartite act of synchronizing the past and present, the traditional/Chinese and modern/Western, enabled early Qing individualist painting to be reinterpreted as an art of modern value and transformed into something new by both Chinese and Western standards. The simultaneous impulses to historicize and renew are both responses to the exigencies of Chinese modernity. Well-exposed to the notions of Social-Darwinism and constantly reminded of the undeniable success of Western powers, early twentieth-century Chinese painters strategized to find an artistic heritage in China’s past that could be compared, no matter how vaguely, to certain aspects of modern Western art. Concurrent with, and partially inspired by, contemporaneous Japanese interest in seventeenth-century individualist art, many late Qing and Republican ink artists readopted and reevaluated yimin painting in order to transform their medium into an art they considered distinctively modern. Their promotion of yimin art and theory as parallel to contemporary European art was aided by the modern means of printing and publishing. Reflecting the drastically changing ideological concerns of Chinese intellectuals in the first half of the twentieth century, the appropriation of yimin art and the reinvigoration of ink traditions were carried out in a variety of fashions by different generations of historians and painters.

This dissertation analyzes the network effects and strategic effects in technology and certification adoption. The first chapter analyzes the externalities of the Electronic Medical Records (EMR) technology. EMR is a multi-level technology, which is characterized by both network effects and strategic effects. Differentiated adoption levels might yield different external effects to neighboring potential adopters. By using a panel of U.S. hospitals' EMR adoption and applying a set of flexible reduced-form regressions, I find the presence of a complementary effect for the first-level EMR adoption, and a competitive effect for higher-level adoption. Chapter two studies the network effects and strategic effects of EMR technology adoption among hospitals using a dynamic structural model. I estimate this dynamic structural model by applying the methods by Bajari, Benkard and Levin (2007) (BBL), and Pakes, Ostrovsky and Berry (2007) (POB), which provide a two-step algorithm for estimating dynamic games. The primary result is the presence of both competition and complementation in this adoption. Furthermore, I perform some counterfactual experiments. The first experiment is to compare hospitals' adoption behaviors in monopoly and duopoly markets, and I find that network effects and strategic interactions are important in the duopoly market. I then perform a policy experiment to examine the effect of the government's incentive programs for EMR adoption, and I find it would greatly stimulate adoption. The third chapter studies the adoption of LEED (Leadership in Energy & Environmental Design) certification, which is an internationally recognized building certification system that evaluates environmental impact. Competition may affect not only certification adoption but also the adoption of quality standards. LEED offers four levels of certifications to indicate the different standards of environmental impact. By using a detailed dataset of LEED registrations in the U.S. and applying the Multinomial Test of Agglomeration and Dispersion (MTAD) developed by Rysman & Greenstein (2005), we find the allocation of certification levels is more agglomerated than independent random choice would predict.

The establishment of the People’s Republic of China in 1949 triggered a deluge of artistic challenges for the Chinese ink painter. Lu Yanshao (1909-1993), an artist skilled in poetry, painting and calligraphy, had built his renown on landscape paintings following a traditionalist style. As of 1949, however, Lu began to make figure paintings that adhered to the guidelines established by the Communist Party.Dramatic social and political changes occurred in the 1950s under the new Communist regime. The Anti-Rightist Campaign, launched in 1957, targeted a large number of educated people, including many artists. Lu Yanshao was condemned as a Rightist and was forced to endure four years of continuous labor reform (laodong gaizao) in the countryside before finally ridding himself of the label of Rightist in 1961. Starting in 1957, Lu shifted his focus from making figure paintings for the country’s sake to his personal interest – creating landscape paintings. In 1959, the artist completed the first twenty five leaves of his famous Hundred-Leaf Album after Du Fu’s Poems. The surviving fourteen leaves combined painting, calligraphy and poetry, and are considered to be early paintings of Lu’s mature phase.Lu Yanshao had studied Confucian texts since he was very young. In this thesis, I argue that changes in his approach to art and to his artistic career after being labeled a Rightist in 1957 can be productively considered from the perspective of the Confucian teaching of Mencius: “If poor, they ["men of antiquity"] attended to their own virtue in solitude; if advanced to dignity, they made the whole kingdom virtuous as well.”That is to say, a scholar privileged to hold office will do everything in his power to serve effectively; if suffering from adversity, however, the scholar will cultivate his personal talents instead. It was by focusing on his own artistic virtue while otherwise suffering as an alleged “Rightist” that Lu gradually entered the mature phase of his artistic career in 1959. Between 1949 and 1957, Lu Yanshao made figure paintings based on the Communist Party’s guidelines because he wanted to contribute to the newly established country through his artwork. Serving the country through art accords with the idea of making “the whole kingdom virtuous.” However, in Lu’s view, the art bureaucracy, which enforced the Party’s ideology, rejected him by labeling him a Rightist in 1957. At this time, Lu experienced a psychological nadir. After years of adjusting himself as a Chinese ink painter in the new society between 1949 and 1957, Lu returned to Chinese landscape painting, developing a brilliant style out of a desperate situation. This maturation in Lu Yanshao’s art can also be considered from a Confucian perspective, especially Mencius’ teaching, “If poor, they [“men of antiquity”] attended to their own virtue in solitude.”

Cancer remains a major public health challenge. The high mortality rate associated with cancer is due in part to the delay of diagnosis which results from the late clinical manifestation of tumors. Identification of biomarkers that can be used to classify tumors should provide more specific and effective strategies for detection, as well as improve monitoring of tumor progression. Several studies were performed in this work. The first study mapped protein expression for a total of 18 samples which include ovarian serous, ovarian surface epithelium, ovarian clear cell, endometrioid carcinoma and breast epithelial cell lines using an automated 2-D liquid fractionation system. Hierarchical clustering analysis was used to classify the different samples according to their protein expression profiles showing that specific types of serous carcinoma cell lines tend to cluster together and different types of cancers can be classified. Potential markerbands used to classify different subtypes of individual cancer can be identified. As an outgrowth of this initial study, the mass mapping technique was also applied to the ovarian serous carcinoma cell lines. In a second study, the 2-D liquid mapping method was also applied to characterize global protein expression patterns in 19 ovarian serous carcinoma tissue samples to develop novel diagnostic biomarkers and allow molecular classification. Nineteen tissue samples could be classified into two different groups with one group associated with stage I and the other group associated with stage III and IV. Proteins that were differentially expressed in different groups were selected for identification by MALDI-TOF-MS or MALDI QIT TOF or LTQ MS. Fifteen of the selected proteins were unequivocally identified as up-regulated in low stage and 45 of the proteins were downregulated. These proteins are known to play an important role in cellular functions and may serve as markers of ovarian serous carcinomas. Studies were also applied to the membrane glyco-proteome using different breast cancer cell lines CA1a and AT1 using multiple lectin extraction where differential proteins were identified using ESI-MS/MS.

This study deals with multi-scale kinetics study of blended cements containing supplementary cementitious materials (SCMs). The objective is to link meso-scale hydration kinetics to macro-scale mechanical properties of concretes. A systematic kinetics study is conducted on single-component and multi-component cementitious systems. Long-term isothermal calorimetry tests are used to record hydration rates covering three orders of magnitude starting right after mixing to 21 days at three temperatures. This new technique enables a better understanding of hydration mechanisms up to 1 month of hydration, which is important for long-term strength development and durability. Early age hydration (up to 20-30% hydration) of single-component cementitious systems (C3S and slag) can be described by the Avrami's nucleation model. Afterwards hydration is continuously slowed down, and can be modeled by a Jander type diffusion model. For more complicated multi-component ordinary Portland cements (OPC), a correction factor is introduced to the Jander's model to describe the simultaneous diffusion processes of multiple compounds. Absolute hydration rate is expressed as the product of absolute rate constant, and a function of relative hydration. This form of rate function makes it easier to evaluate the influencing factors on hydration. Activation energy is determined from the absolute rate constant, and found to be constant for nucleation and diffusion stages. The constant activation energy is explained by the fact that the same chemical reactions occur and produce the same reaction products, which can be verified by the TGA results. The absolute-rate based hydration kinetics was used to improve the conventional relative-rate based maturity functions, and to develop a computational procedure to predict hydration development under non-isothermal conditions. A new methodology is developed to separate the contributions of SCM's pozzolanic reaction from OPC hydration. This approach facilitates the evaluation of SCM's reactivity, the optimization of blended cements, and the assessment of compatibility of SCMs with cements. An evaluation procedure is proposed by utilizing a quantitative link between compressive strength and heat of hydration established in this study. Using this procedure, only limited testing is needed to investigate blended cements, thus circumventing the cumbersome strength testing usually used in the literature.

Bacteria, bees and birds often work together in groups to find food. A group of robots can be designed to coordinate their activities. Networked cooperative UAVs are being developed for commercial and military applications. In order for such multiagent systems to succeed it is often critical that they can both maintain cohesive behaviors and appropriately respond to environmental stimuli. Stimulated by the growing interest in biomimicry of the mechanisms of foraging and swarming for use in engineering applications, this dissertation focuses on mathematical modeling and analysis of stability properties of swarms. We construct a generic swarm model which considers the interagent attractions and repulsions and the effect of resource profiles. Based on this model, we study its cohesion properties in a stability-theoretic framework. First, we consider the effects of sensor noise and error on sensing resource profiles on stability of continuous-time swarms and give the conditions for the swarm to achieve uniformly ultimate boundedness (UUB). Next, we analyze the stability properties of the swarm model in discrete time and obtain stability properties similar to the continuous-time case. Then, we extend the results by adding an interagent sensing network topology, asynchronism and time delays into the model and studying their effects on stability. The conditions under which the system trajectories are uniformly ultimately bounded and exponential stability can be achieved are given. Such stability analysis is of fundamental importance if one wants to understand the coordination mechanisms for groups of autonomous vehicles or robots where inter-member communication channels are less than perfect.

The problem of the free vibration of thick multi-layered viscoelastic cylinder is studied and an analytical solution is presented. An analysis for the vibration damping of a three-layered arrangement, taking into account the shear deformation of viscoelastic core, has be reported and an approach to characterize a wide range of viscoelastic material data is discussed. A general analysis was reported that included varying both shear modulus and material loss-factor for the core viscoelastic layer. The effects of varying core shear modulus and material loss-factor on the natural frequencies and their corresponding modal loss-factor are investigated. It would [sic] useful for obtaining an optimized arrangement for damping effectiveness.