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Can urban areas - such as named areas - as parts of a whole city be defined and described in terms of their relationship to the surroundings? How is the continuous urban grid spatially partitioned into different parts? These questions have been extensively discussed in the theoretical and professional literatures, but there is a relative paucity of references of any precision to the spatial form of areas. The thesis, using a rigorous and empirical methodology developed in the theory of space syntax, seeks to define boundaries between urban areas in terms of the way the areas are spatially embedded into the multi-scale contexts. And then the thesis intends to explore geometric and spatial mechanisms in the formation of the areas. After conducting a pilot study of Canary Wharf and Brindleyplace, the thesis conjectures that area boundaries can be treated as discontinuities in the configuration of space, and such boundaries are shown in some way in the pattern of spatial connection of the urban grid outward from each individual space with an increase of scale, ranging from its immediately neighbouring spaces to the whole grid. Several space syntax techniques are then developed to detect and illustrate the area discontinuities. On this basis, a periodic patchwork pattern, meaning the urban grid, is partitioned into a set of periodic and discrete parts, is brought to light in the empirical studies of the central districts of London and Beijing as well as the London Docklands. It can be argued that the discontinuities between urban areas can be typically considered as the fuzzy boundaries supporting functional differentiation of areas, without spatially self-contained or geometrically limited boundaries. This thesis concludes that it is the syntactic relations of all individual spaces and their multi-scale contexts that account for the spatial definition and aggregation of urban areas.

Typical aging is associated with declined cognitive functions and neural deterioration. This thesis investigates the effect of normal aging on social perception of facial emotion and facial identity. Firstly, this thesis examines older adults’ ability to perceive facial emotions and facial identities with subtle changes using behavioural investigations. It is revealed that normal aging is linked with declined ability to make fine-grained judgements in the perception of facial emotion (anger and happiness) and facial identity (upright- and inverted-), but not for facial traits judgement. In addition, the relationship between age and each face perceptual performance were explored using regression model fitting. Additionally, this thesis further examines whether typical aging is associated with the perception of subtle changes in facial emotion and facial identity with older adult faces, and whether the age- related facial identity perceptual decline is a face-specific decline or it extends to non-social perception. I developed novel tasks that permitted the ability to assess facial emotion (happiness perception), facial identity, and non-social perception (object perception) across similar task parameters. It is observed that older adults have decreased ability to make fine- grained judgements in the perception of happiness and facial identity (from older adult faces), but not for non-social object perception. These behavioural findings are discussed with theories within the current literature. This thesis also explored the neural mechanisms underlying social perception in older adults using non-invasive high-frequency transcranial random-noise stimulation (tRNS) and electroencephalogram (EEG). The results revealed that stimulating inferior frontal cortex facilitates older adults’ anger perception, especially low- performing older adults. The event-related potentials (ERPs) results have shown that older participants exhibited neural overactivation in the left frontal and centromedial region (100- 200ms stimuli onset) and frontal region (250-850ms stimuli onset) during emotion perception. These findings are discussed in the context of existing literature on normal aging and social perception.

As the More-Electric Aircraft (MEA) has been identified as a major trend of future aircraft, the on-board Electrical Power System (EPS) will see significant increased numbers of Power Electronic Converters (PECs) and motor drive systems. In order to study the behaviour and performance of the EPS in MEA, extensive simulation studies need to be done during the system design process. This in return, gives the need to have computationally efficient and accurate models to reduce the design period. In this thesis, the Dynamic Phasor (DP) is used for modelling EPS in the MEA. The DP technique is a general averaging method and naturally a frequency-domain analysis tool. Compared with other averaging models, which is only efficient under balanced conditions, the DP model maintains efficiency under both balanced and unbalanced conditions. The DP technique has been widely used in modelling the constant, single frequency EPS. In this thesis, the DP technique is extended to modelling time-varying frequency EPS. The application of DP in modelling a multi-generator, multi-frequency system is for the first time, developed in this thesis. The developed theory allows a wider application of the DPs. The developed DP model covers key elements in MEA electrical power systems, including the synchronous generator, control, transmission lines, uncontrolled rectifiers, PWM converters and 18-pulse autotransformer rectifier units. The DP model library developed based on this thesis allows the flexibility to study various EPS’s by integrating elements from the library. A twin-generator aircraft EPS, which is based on the More Open Electrical Technology (MOET) large aircraft EPS architecture, is used to demonstrate the application of DP models. Comparing the DP model with the ABC model (models in three-phase coordinates) and the DQ0 model (models in a synchronous dq frame), the efficiency and the accuracy of the DP model are demonstrated under both balanced and unbalanced conditions.

Our connections to the digital world are invoked by brands, but the intersection of branding and interaction design is still an under-investigated area. Particularly, current websites are designed not only to support essential user tasks, but also to communicate an institution's intended brand values and traits. What we do not yet know, however, is "which design factors affect which aspect of a brand." To demystify this issue, three sub-projects were conducted. The first project developed a systematic approach for evaluating the branding effectiveness of content-intensive websites (BREW). BREW gauges users' brand perceptions on four well-known branding constructs: "brand as product," "brand as organization," "user image," and "brand as person." It also provides rich guidelines for eBranding researchers in regard to planning and executing a user study and making improvement recommendations based on the study results. The second project offered a standardized perceived usability questionnaire entitled DEEP (design-oriented evaluation of perceived web usability). DEEP captures the perceived website usability on five design-oriented dimensions: "content," "information architecture," "navigation," "layout consistency," and "visual guidance." While existing questionnaires assess more holistic concepts, such as ease-of-use and learnability, DEEP can more transparently reveal where the problem actually lies. Moreover, DEEP suggests that the two most critical and reliable usability dimensions are interface consistency and visual guidance. Capitalizing on the BREW approach and the findings from DEEP, a controlled experiment (N = 261) was conducted by manipulating interface consistency and visual guidance of an anonymized university website to see how these variables may affect the university's image. Unexpectedly, consistency did not significantly predict brand image, while the effect of visual guidance on brand perception showed a remarkable gender difference. When visual guidance was significantly worsened, females became much less satisfied with the university in terms of brand as product (e.g., teaching and research quality) and user image (e.g., students' characteristics). In contrast, males' perceptions of the university's brand image stayed the same in most circumstances. The reason for this gender difference was revealed through a further path analysis and a follow-up interview, which inspired new research directions to unpack even more the nexus between branding and interaction design. [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.]

Nitric oxide (NO) is a multifunctional molecule that contributes to a broad range of physiological activities. However, the therapeutic potential of NO has been severely impaired by its short half-life (less than 5 seconds) and limited diffusion distance (20-160 µm) in human tissues. In addition, NO activity is strongly dependent on its concentrations and locations. Therefore, there is a need to develop NO delivery technologies that enable controllable and tunable NO administration. Current NO delivery systems include encapsulation of NO donors into prefabricated scaffolds or enzyme-prodrug therapy approach. However, the former is limited by the finite deliverable NO while the latter is challenged by the intrinsic low stability of natural enzymes. A crafty design to circumvent these limitations is to develop enzyme mimics that can catalyze endogenous NO prodrugs to produce NO. This thesis focuses on the design, synthesis, and applications of a new class of zinc-based enzyme mimics that enables sustained NO delivery. I synthesized ZnO particles using a chemical precipitation method and provided the first report documenting that ZnO mimics the activities of glutathione peroxidase and galactosidase to catalyze endogenous S-nitrosoglutathione (GSNO) and exogenous β-gal-NONOate to produce NO. Physiologically relevant NO levels were achieved by adjusting the concentrations of ZnO and NO prodrugs. ZnO enabled NO generation in human serum and preserved its catalytic efficacy for at least 6 months, which is highly beneficial for long-term biomedical applications. I further investigated the influence of morphology and surface modification on the catalytic activity of ZnO towards NO generation and found that: 1) the NO-generating activity of ZnO is morphology-dependent due to the different crystal growth directions of the particles and 2) ZnO retained 60 % of its NO-generating activity after modifying its surface with zeolitic imidazolate framework (ZIF-8). ZnO/ZIF-8 enabled NO generation from GSNO, S-Nitroso-N-Acetyl-D,L-Penicillamine (SNAP), and β-gal-NONOate. I also developed a multifunctional enzyme mimic by encapsulating superoxidase dismutase, a natural enzyme with free radical scavenging ability, into ZnO/ZIF-8, which holds potential for cancer therapy. The findings presented in this thesis open new routes to the next generation of NO-releasing biomaterials and devices in diverse biomedical applications.

My dissertation is composed of three chapters. The first chapter is on the asymptotic trimming and rate adaptive inference for heavy-tail distributed estimators. The second chapter is about the identification of the Average Treatment Effect for a two threshold model. The last chapter is on the identification of the parameters of interest in a binary choice model with interactive effects.

During brain development, neurons extend axons to reach their targets, a process called axon pathfinding or axon guidance. A variety of guidance cues have been identified in the developing nervous system such as Netrins, Semaphorins, Ephrins and Slits. In the developing spinal cord, the floor plate strongly expresses both Netrins and Slits, which collaborate with each other to attract pre-crossing and repel post-crossing commissural axons, respectively. Slit repulsion is silenced in pre-crossing commissural axons, which allows commissural axons to be attracted by Netrins and project toward the floor plate. However, the Slit repulsion is up-regulated and the Netrin attraction is inhibited in post-crossing axons, which prevents commissural axons from re-crossing the midline. Currently, the silencing mechanisms of attraction vs. repulsion are not fully understood. Previous studies suggested that regulation of protein levels of endogenous Robos, Slit receptors, plays an important role in these processes. Robo1 is expressed at extremely low levels in the growth cone of pre-crossing commissural axons. However, expression of Robo1 is dramatically up-regulated in commissural axons after the midline crossing. How is the expression of Robo1 regulated? Down-regulation of the target gene expression by microRNAs is crucial for neurogenesis, neuronal maturation and brain development. Our preliminary studies indicate that several microRNAs targeted the three prime untranslated region (3’UTR) of Robo1 are differentially expressed in the developing mouse dorsal spinal cord. Over-expression of these microRNAs into E13 mice spinal cord neurons suppressed expression of endogenous Robo1. Therefore, we hypothesize that microRNAs are able to regulate Robo1 expression and play an important role in spinal cord commissural axon projection. We found that the regulation of Robo1 gene expression is mediated by Robo1 3’UTR. miR-92, a highly conserved miRNA in multiple species, represses Robo1 expression in a miR-92-MRE dependent manner. Moreover, both in situ hybridization and immunohistochemistry in chicken embryos showed that gga-miR-92 and Robo1 have a differential expression pattern in the developing chicken spinal cord. miR-92 is highly expressed in precrossing commissural neurons, while Robo1 is strongly expressed in postcrossing commissural neurons. Furthermore, miR-92 can specifically repress Robo1 by translational repression rather than mRNA degradation and directly regulate Robo1 local translation in the growth cone. Additionally, results from in vitro explants co-culture assay suggested that miR-92 can control Slit2 sensitivities in Slit/Robo1-mediated commissural axon guidance and midline crossing by regulating Robo1 in a miR-92 MRE dependent manner. Finally, the interaction between Robo1 and miR-92 is required in commissural axon projections in vivo.

The dissertation consists of three distinct but related projects. We consider regression model fitting, variable selection in regression, and autocorrelation estimation in time series. In each procedure we formulate the problem in terms of minimizing an objective function which adapts to the given data. First we propose a robust M-estimation procedure for regression. The main purpose of the proposed methodology is to develop a procedure that adapts to light/heavy tailed, symmetric/asymmetric distributions with/without outliers. We focus on studying the properties of the maximum likelihood estimator of the asymmetric exponential power distribution, a broad distribution class that holds both Normal and asymmetric Laplace distributions as special cases. The proposed methodology unifies least squares and quantile regression in a data driven manner to capture both tail decay and asymmetry of the underlying distributions. Finite sample performance of the method is exhibited via extensive Monte Carlo simulation and real data applications. Second, we capitalize on the success of the proposed method and extend it to a variable selection procedure that selects the important predictors under a sparse setting. Quantile regression Lasso, i.e., quantile regession with $L_1$ norm on the regression coefficients for regularization is a robust technique to perform variable selection. However which quantile should be adopted is unclear. The proposed methodology introduces a way to choose the most ``informative' quantile of interest that is used in the adaptive quantile regression Lasso. A modified BIC criterion is used to select the optimal tuning parameter. The proposed procedure selects the quantile based on the log-likelihood of the asymmetric Laplace distribution, and aims to perform the best quantile regression Lasso which is confirmed in both simulation study and a real data analysis. Third, we focus on alleviating the underestimation issue of the sample autocorrelation in linear stationary time series. We first formulate autocorrelation estimation into a least squares problem and then apply a penalization to regulate the autocorrelation estimate. An adaptive sequence is proposed for tuning parameter and is shown to work well for stationary time series when the sample size is small and correlation is high.

This dissertation develops and tests a theoretical model of the role of a mindfulness intervention in promoting job performance in service settings. I examine the client-focused mechanisms—attentiveness, perspective taking, and response flexibility—and individual (i.e., employee agreeableness), social (i.e., perception of workgroup service climate), and job (i.e., work overload) contingencies of the relationship between a mindfulness intervention and job performance. I conducted a pretest-posttest field experiment of 72 health care professionals in a health care organization with intervention (i.e., mindfulness meditation) and active control (i.e., wellness education) conditions and repeated measures from health care professionals and their patients over 15 days. Confirmatory factor analyses suggest that the three client-focused mechanisms were represented by a higher-order construct of patient centered behavior. Multilevel modeling and latent growth modeling suggest that the two conditions are distinct; compared with active control, the intervention yields pre-to-post increases in daily mindfulness and work behaviors including self-ratings of job performance and proactive patient care and patient ratings of patient centered behavior. Multilevel mediation analysis suggests that patient ratings of patient centered behavior fail to mediate the effect of a mindfulness intervention on patient satisfaction with job performance. Multilevel moderated mediation analyses suggest that agreeableness, perceived workgroup service climate, and work overload do not moderate the effect of a mindfulness intervention (via patient ratings of patient centered behavior) on patient satisfaction. Nonetheless, compared with active control, the mindfulness intervention yields higher patient rated patient centered behavior for health care professionals who have a higher level of agreeableness.

We construct a Hopf action, with an invariant trace, of a bicrossed product Hopf algebra $\cH=\big( \cU(\Fg_1) \acr \cR(G_2) \big)^{\cop}$ constructed from a matched pair of Lie groups $G_1$ and $G_2$, on a convolution algebra $\cA=C_c^{\ify}(G_1)\rtimes G_2^{\delta}$. We give an explicit way to construct Hopf cyclic cohomology classes of our Hopf algebra $\cH$ and then realize these classes in terms of explicit representative cocycles in the cyclic cohomology of the convolution algebra $\cA$.

As the space closely related to a country’s political system and its administration, administrative buildings reflect the interaction between country, society and citizens from ancient times. What is the relationship between ideologies and the design of administrative buildings? What are the design patterns of administrative buildings? How to design a good administrative building in today’s China? Based on the above questions, the thesis consists of two major parts. The first part focuses on Western administrative buildings: the historical evolution and the contemporary trends have been studied and analyzed. Through typology studies, the design patterns are summarized at three levels: macro level—three types of building location of administrative building in the city; meso level—four forms of square space; micro level—the architectural design influenced by three main factors. The second part of the thesis focuses on the implications in China. It starts with the current issues of administrative buildings in China, followed by the study of vernacular architecture and yamen buildings in Guizhou, and as the result, a scheme for Fenggang Administrative Center has been proposed to illustrate a new set of design strategies. The research attributes great importance to the urban features of administrative buildings, and tries to establish an open frame for the design patterns of administrative buildings, not only for historical studies but also for future designs. By the research and the design, the thesis makes a statement that administrative buildings built with a more appropriate scale, more public presence and more cultural identities are needed for the emerging civil society.

In this thesis, the generalized inverseWeibull distribution including the proportional reverse hazard and Kumasraswamy generalized inverse Weibull distributions are presented. Properties of these distributions including the behavior of the hazard and reverse hazard functions, moments, coe_cients of variation, skewness,and kurtosis, _entropy, generalized entropy, Fisher information matrix, informational energy are studied. Estimates of the model parameters via several methods including maximum likelihood (MLE), and method of moments (MME) are presented.

This study explores the features of Lead Monofluoride (PbF) as a candidate in determining the permanent electric dipole moment of the electron (e-EDM). It accomplished three goals: 1) Measurement of the molecular dipole moments of the PbF molecule, 2) Proposal of the biased Stark guides necessary for the beam resonance detection of the e-EDM sensitive transition, and 3) Re-evaluation of the magnetic g-factor of the PbF molecule. All of these efforts are made toward a non-zero e-EDM measurement, which has great significances in revealing the New Physics beyond the Standard Model.

In the past two decades, there has been an explosive increase in demands for high-rate wireless communications featuring high reliability and low computational complexity. Therefore, many efforts have been made to understand the fundamental performance limits of wireless channels and the interlocking concepts of wireless communication techniques. In this thesis, we focus our study on some crucial wireless communication setups, namely multi-user, multiple-input multiple-output (MIMO) and cooperative communications in wireless networks. The purpose of the research is to develop communication strategies with capacity-achieving performance and low computational complexities. At the heart of this research lies a key technique which is referred to as _superposition coding_ in which the receiver sees the superposition of different levels of coded information. By exploring the concept of superposition coding, a unified view for these important communication setups are formed and the interplay of the concepts of these scenarios are demonstrated. For the setups under consideration, we first study their fundamental performance limits from information theoretic perspective. We learn that superposition coding schemes with interference cancellation based decoding are capacity-achieving for the majority of cases. Then, we develop practical superposition coding schemes featuring multi-level binary error coding and iterative soft interference cancellation and decoding. The developed approaches outrun existing communication schemes in either performance or computational complexities. For fading channels, we show that properly designed superposition coding scheme utilizes the degrees of freedom of the communication channel more efficiently while achieving the highest diversity gain. The advantageous features of the superposition coding technique will make it very attractive for practical implementations.

In this dissertation, two problems related to bipedal robot walking are presented. The first problem is the influence of parallel knee joint compliance on the average power cost of walking in an underactuated planar bipedal robot, ERNIE. The second problem is the design of walking controllers that induce aperiodic bipedal robot walking. It has been found that compliance plays important roles in walking and running in animals. Compliance has been used in robotic bipedal machines to improve energetic efficiency or reduce the peak power demand on the robot's actuators. This dissertation presents numerical and experimental studies of the influence of parallel knee joint compliance on the average power cost of walking in an underactuated planar bipedal robot, ERNIE. Four scenarios were studied: one without springs and three with springs of different stiffnesses and preloads. Optimal gaits in terms of average power cost for various speeds were designed for each scenario. It was found that for low-speed walking, soft springs are helpful to reduce power cost, while stiffer springs increase power cost. For high-speed walking, it was found that both soft and stiff springs reduce the average power cost of walking, but stiffer springs reduce the cost more than do softer springs. The second problem addressed in this dissertation is aperiodic walking controller design. The ability to walk stably in varying environments or with different tasks, such as stepping over stones, is of great interest in bipedal walking. In these scenarios, the walking is not periodic. This dissertation presents a new definition of stable walking that is not necessarily periodic for a class of biped robots. The inspiration for the definition is the commonly-held notion of stable walking: the biped does not fall. To make the definition useful, an algorithm is given to verify if a given controller induces stable walking. Also given is a framework to synthesize controllers that induce stable walking. The results are illustrated with numerical simulation and experiments. This dissertation also presents details of a modeling procedure for the experimental bipedal robot, ERNIE, and explores the possibility to apply iterative learning control to bipedal walking.

Multiple-input multiple-output (MIMO) wireless technology is an emerging cost-effective approach to offer multiple-fold capacity improvement relative to the conventional single-antenna systems. To achieve the capacities of MIMO channels, MIMO bit-interleaved-coded-modulation (BICM) systems with iterative detection and decoding (IDD) are studied in this thesis. The research for this dissertation is conducted based on the iterative receivers with convolutional codes and turbo codes. A variety of MIMO detectors, such as a maximum a posteriori probability (MAP) detector, a list sphere detector (LSD) and a parallel interference canceller (PIC) together with a decision statistic combiner (DSC), are studied. The performance of these iterative receivers is investigated via bounding techniques or Monte-Carlos simulations. Moreover, the computational complexities of the components are quantified and compared. The convergence behaviors of the iterative receivers are analyzed via variance transfer (VTR) functions and variance exchange graphs (VEGs). The analysis of convergence behavior facilitates the finding of components with good matching. For a fast fading channel, we show that the &quotwaterfall region&quot of an iterative receiver can be predicted by VEG. For a slow fading channel, it is shown that the performance of an iterative receiver is essentially limited by the early interception ratio (ECR) which is obtained via simulations. After the transfer properties of the detectors are unveiled, a detection switching (DSW) methodology is proposed and the switching criterion based on cross entropy (CE) is derived. By employing DSW, the performance of an iterative receiver with a list sphere detector (LSD) of a small list size is considerably improved. It is shown that the iterative receiver achieves a performance very close to that with a maximum a posteriori probability (MAP) detector but with a significantly reduced complexity. For an iterative receiver with more than two components, various iteration schedules are explored. The schedules are applied in an iterative receiver with PIC-DSC. It is shown that the iterative receiver with a periodic scheduling outperforms that with the conventional scheduling at the same level of complexity.