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Rapid advances in infrastructure health monitoring and sensing technologies allow monitoring of assets continuously and in real-time throughout their life span. However, smart and automated techniques for decision-making (e.g. maintaining or improving infrastructure performance) are in their infancy. The revolution in new sensing capabilities has led to rapidly increasing volumes of data, which makes traditional data analysis techniques inadequate. Adoption of Big Data (BD) analytics and Artificial Intelligence (AI) techniques is urgently needed to automatically integrate information from multiple sensors, extract knowledge and inform decision-making. A novel damage identification and localisation approach is proposed, which utilises multi-level data fusion and anomaly detection techniques. Numerical models of a simply supported bridge and a continuous bridge were simulated for data generation. Accelerations, deflections and bending moments obtained at multiple sensor locations when the bridge is subjected to a moving vehicle were used as the input. A damagesensitive feature was established via coupling principal component analysis with the Mahalanobis distance, allowing for initial data dimensionality reduction and information integration. Anomaly detection using a deep convolutional autoencoder was performed to identify the presence of damage on the bridge. It is demonstrated that the proposed approach is independent of the mass and speed of the moving vehicles. The approach is highly successful in identifying and localising damage(s), even for extremely small damage severity (e.g. 1% reduction in the second moment of area of an element with 0.5m in length in the simply supported bridge, and 15% reduction in the second moment of area of an element with 0.166m in length in the continuous bridge), and multiple damaged cases on the bridges, achieving accuracies of over 93% for all tested cases of the simply supported bridge and over 91% for the majority of the tested cases of the continuous bridge. The proposed damage localisation approach can accurately determine damage location(s) for both single and multiple damage cases. It is shown how the proposed framework can be adopted for early damage detection to enable reliable decision-making and maximise structural safety.

The liver is the largest solid organ in the human body, and functions to detoxify various chemicals, metabolize nutrients, and support almost every organ in the body. Thus, the liver is prone to many diseases. Non-alcoholic fatty liver disease (NAFLD), the most common liver disease, is an umbrella term for a range of conditions compromising hepatic steatosis, non-alcoholic steatohepatitis (NASH), fibrosis and cirrhosis without alcohol consumption, which may highly increase the risk of hepatocellular carcinoma, one of the leading causes of cancer-related death. Diabetes mellitus, one of the most common chronic diseases, has an intimate association with the onset of NAFLD. In addition, hepatic disease can cause the disordered metabolism of glucose, which is regarded as the pathophysiologic basis of diabetes in liver disease. MicroRNAs (miRNAs), the small and non-coding RNAs, are involved in various biological processes by regulating gene expression at transcriptional or translational levels. Ample studies have revealed that the aberrant levels of miRNAs strongly correlate with the pathogenesis of metabolic diseases. In addition, long non-coding RNAs (lncRNAs) have been regarded as co-operators of miRNAs, involving in the progression of diseases. However, the mechanistic role of miRNAs and miRNA-lncRNA-mRNA interplay in the development of the liver disease have not been investigated clearly. Therefore, my research aimed to determine the physiological and pathological roles of non-coding RNAs in the liver through molecular and bioinformatics approaches, in order to shed new light on the therapeutical potential of miRNAs in ameliorating liver diseases.

Knowledge is one of the most important resources in any organizations. Construction is a knowledge-intensive industry, in which organizations are known for the delivery of products and services, relying on various knowledge. In construction projects, different disciplinary teams have knowledge learned and accumulated from their experience of construction practice or education. However, due to the fragmented nature of construction projects, it is difficult for the knowledge of each discipline to be integrated for solving problems in a specific project phase. For example, in the design stage, it is difficult to apply the knowledge of the contractor and the facility management (FM) team to solve potential problems in construction and FM proactively. Compared to generic information technology (IT) tools, building information modelling (BIM) provides an integrated platform that allows multiple disciplinary teams to manage project-related data collaboratively. In addition, BIM can be seen as a process throughout the project life cycle, in which the project lifecycle data are accumulated and recorded. Therefore, the study attempts to explore whether the knowledge related to construction and FM can be more easily applied to the design stage of the project with the support of BIM. In order to understand how BIM can improve KM in construction projects, it is necessary to understand the status of KM in current construction projects, including the difficulties of KM and the strategies being used. Also, the process of involvement of contractors and FM teams in the design stage should be explored. As BIM has distinguishing features compared to generic IT, it is also necessary to explore how some of these features can help the proactive application of construction and FM-related knowledge to the design stage of the projects. In addition, the expectation of BIM-supported KM for early application of construction and FM-related knowledge in design stage should be identified. Based on the understanding of the above research questions, a KM system integrated to BIM is developed. This research used mixed methods to achieve the research objectives mentioned above. In order to collect in-depth information from the construction industry, semi-structured interview as a part of the mixed methods was adopted to obtain construction practitioners' views on the current status of KM in construction projects, as well as the strategies for early involvement of contractors and FM teams and the aspects that need to be improved. The practitioners' expectations of BIM-supported KM were also identified through semi-structured interviews. Based on the results of the semi-structured interviews, in order to apply construction and FM-related knowledge in the design stage, it is needed to enable the knowledge generated during construction and FM phases to be captured. Also, the captured knowledge should be easily retrieved in the design stage. Accordingly, a KM system is developed to achieve this purpose. The waterfall method is used as a software development method to develop the KM system. The parametric modelling of BIM is used for improving knowledge capture in the developed system. The parameters used to capture knowledge cases are pre-defined in the BIM model and are compatible with the CBR and NLP modules. Moreover, since BIM is a process throughout the project life cycle, the knowledge generated during the construction and FM stages can be captured by BIM. The captured knowledge will be stored in a centralised knowledge base for the future use. On the other hand, this system combines case-based reasoning (CBR) with deep neural network-based natural language processing (NLP) as an innovative retrieval method. CBR presents the knowledge context through attributes, while NLP is used to evaluate the similarity of detailed text description between knowledge cases. The weights of CBR attributes affects the performance of CBR. Statistical technique on the large amounts of data collected is required for weight determination. For this reason, this research adopts a questionnaire survey as a quantitative method to determine the weight of each attribute in CBR to improve its accuracy. By using the developed system, the captured knowledge can be proactively discovered and applied in the design stage of future projects through the retrieval tool supported by the CBR and NLP. This developed system is validated through a case study. This research combines conventional KM tools, such as CBR and NLP, with BIM to facilitate the proactive application of construction and FM related knowledge in the design stage of projects. The parametric modelling of BIM is applied in this research for knowledge capture. Besides, this research identified distinctive features of BIM that can be used to improve KM. These distinctive features provide BIM-supported KM with some advantages over generic IT-based KM and point out the research roadmap for future research on BIM-supported KM. It is hoped that this study becomes one of the frontier research attempts that initiate an idea of the transformation from BIM into building knowledge modelling (BKM).

Surface tension is one of the most important physical properties that determines the behaviour of bubbles. While the effect of nanoparticles and surfactants on the surface tension of bubbles have been widely studied, the role of microparticles has not received too much attention. In this work, the effect of silica microparticles on the surface tension and the behaviour of bubbles was explored, both for bubbles at rest and during dynamic processes such as pinch-off, oscillation and coalescence. The influence of microparticles on the shape and surface tension of static bub- bles grown from a submerged nozzle was investigated first using a modified sessile bubble method. The results show that particles were in static equilibrium at the static bubble, without any change in bubble surface tension. In addition, it was found that the presence of particles at the bubble interface led to a change in the bubble contour, similar to the effect of the changes in surface tension for uncoated bubbles, which explains why classical sessile bubble tensiometry overestimated the surface tension of particle-laden bubbles. Secondly, the influence of microparticles on the surface tension and shape defor- mation during and immediately after pinch-off was investigated. It was found that microparticles at the deforming air-liquid interfaces generated surface pressure and reduced surface tension of the interfaces, leading to a hindered shape deformation compared to that of uncoated bubbles. Moreover, it was found that changing bubble surface coverage has noticeable effect on the surface pressure after pinch-off, while not during pinch-off. In addition, increasing particle contact angle and particle size both led to an increase in the surface pressure during pinch-off. Experiments on bub- ble oscillations were conducted, harmonic analysis shows the presence of particles at bubble surfaces decreased the damping rate of the dominant harmonic signifi- cantly while having a minor influence on the oscillation frequency during the shape oscillation of the bubbles. Lastly, the influence of microparticles on the surface tension and the neck growth dynamics during the early stage of bubble coalescence was studied. Results show that the particles at the bubble surface hindered the neck growth dynamics due to the generation of the surface pressure by particle interactions. The existence of the surface pressure lead to a lower surface tension compared to that of the uncoated bubbles, with coarser particles generating higher surface pressure and correspond- ing to lower surface tension. This thesis provided a systematic study of the behaviour of particle-laden bub- bles using high-speed photography, macrophotography and image analysis tech- niques. This work contributes to fundamental understanding of the surface tension of particle-laden interfaces both on and off equilibrium.

Human African trypanosomiasis (HAT) is fatal unless treated. Pentamidine has been used to treat first-stage (hemolymphatic) HAT since the 1940s, but it is ineffective against second-stage (meningoencephalitic, or central nervous system) infection. Research has suggested that hOCT1 and P-gp are involved in the transport of pentamidine across the blood-brain barrier (BBB). The aim of this study was to investigate if through the formation of ion-pairs the passive diffusion and hOCT1 and P-gp mediated BBB transport of pentamidine could be improved.

Combined with five research articles, this thesis aims to elaborate the ongoing investigations on Chinese economy in the field of its development studies with emphasis on its utilization of FDI including both inbound and outbound investment and labour market. From the 1st opium war a century ago, China was suffering from the un-unified sovereignty as a colonized country. Its economy and development were left far behind. After a century since that, the economic reform of China in 1978 has achieved great success in the sense that it enables China to become the most rapidly growing country and the second largest economy in the world. This opening up strategy, followed by a series of polices has made China one of the most favourite host countries for receiving FDI. As a result, the inward FDI can bring the benefit of economic growth for China on the one hand, but it has long been argued that it can also affect the labour allocation and income inequality on the other. How the previous Chinese-foreign relationship matters in the relationship between inward FDI and Chinese labour market and whether the FDI enlarges the income inequality as the literature suggested will be answered in the following chapters. Also, the China’s outward FDI has been increasing rapidly as China has gained important international status and increasingly played a more crucial role in international economy in recent years. What determines the Chinese outward FDI from a Chinese-foreign relationship (the cultural aspect) is the major motivation for another empirical research. The external factors such as FDI are important to understand the Chinese Economy. Yet, the internal factor such as rural labour transfer should not be neglected. Therefore, we also conduct 2 research papers on labour economics by investigating the rural labour on-farm transfer decisions and the role of grandparenting-life quality-life satisfaction. Therefore, this thesis consists two articles to illustrate the relationship between inward FDI and labour market and income inequality, respectively. In the 1st article, we show that the relationship between inward FDI and employment is affected by different previous colonial powers in either positive or negative ways due to the different institutions they may have left. In the 2nd paper, I revisit the relationship between inward FDI and vertical income inequality in China. I find that inward FDI should not be blamed for the increasing of income inequality in China as it should in some other cases. Next, we study the Confucius Institute and the Chinese outward FDI, the results of which provide evidence on how cultural familiarity ties China with the world and boots its outward FDI as placed in the 3th paper. The 4th empirical study looks into the Chinese labour market more specifically with major focus on the rural labour transfer. We find that different capital endowments play key roles on rural households’ on-farm transfer decisions. The last research article investigates the grandparenting-life quality-life satisfaction and shows that the grandparenting has a favourable effect on grandparents’ life quality and life satisfaction.

Functional outcomes of ongoing thought show both costs and benefits. Yet, the reason for its heterogeneity remains unclear. The executive failure and representational accounts stemmed from different psychological research approaches to understand ongoing thought. The executive failure account examines why changes in ongoing thought happen, while the representational account seeks to explain how humans generate ongoing thought. The attentional system and the default mode network are the common neural processes of both theoretical accounts, but interacting in a contradicting manner. The two accounts can be seen as competing theories of ongoing thought. However, in the family resemblance view (Seli et al., 2018), the two theoretical accounts potentially serve as two component processes of one phenomenon. One possible solution to this conflict could be that under different global neural configurations, the two networks support different cognitive functions. The thesis sets out to present evidence supporting of the family resemblance view and to begin research on the ontology of the component processes in ongoing thought. Neural cognitive hierarchy is the potential explanation of the heterogeneity. The current thesis adopts sparse canonical correlation analysis to incorporate the neural and behavioural aspects of ongoing thought. The data suggests ongoing thought is a collective phenomenon with many types of experience driven by the connectivity patterns in the default mode network. Each type of experience associated with their unique functional outcomes and neural hierarchies at the whole-brain level. Cognitive flexibility and the balance of segregation and integration between the transmodal systems and the rest of the cortex determines the immersive details. The current findings suggested the importance of whole-brain neural hierarchies to ongoing thought. The confirmation of these trait level findings at a state level are necessary to gain more insights into the architecture of the component processes.

Polypills have been proven to improve the patient compliance to multi-drug treatment. However it is still poorly understood when the drugs of a polypill formulation are manufactured as a mixture. The formations of co-amorphous mixtures are one of the possible results of blending multiple drugs in a single process. This project investigated the co-amorphous mixtures of two model drugs, felodipine and paracetamol prepared by melt-cool method. The rationale of the model drug selections is based on the high interaction potentials (hydrogen bonding) between the two drugs as both contain hydrogen donors and acceptor groups. Three molar ratios of the co-amorphous systems of paracetamol and felodipine (P-F) were prepared and their physical stabilities were studied using SEM, DSC, ATR-FTIR and PXRD. It was noted that there is no clear intermolecular interaction between felodipine and paracetamol was identified. Higher paracetamol content led to poorer physical stability of the co-amorphous system which also led to hindered release of paracetamol. The dissolution rates of felodipine from the co-amorphous systems showed no significant improvement in comparison to crystalline felodipine indicating the rapid recrystallization of felodipine during the dissolution process. However the linear nearly zero order release of paracetamol indicated the entrapment of paracetamol in the recrystallized felodipine lattice. This confirmed the formation of co-amorphous mixture without specific hydrogen bonding between the two species. Soluplus was used as the polymeric excipient with an attempt to further improve the physical stability of the co-amorphous systems. The stability of P-F 1:1 loaded Soluplus HME extrudates showed significant improvement than the co-amorphous sample. However no significant dissolution enhancement was observed. This could be partially attributed to the use of the extrudates in the rod form instead of power form in the dissolution tests. Controlled release of paracetamol and poor dissolution of felodipine were obtained from the HME samples indicating the poor solubility enhancement capability of Soluplus in this formulation. The results of this project provided further understanding of the behaviour of co-amorphous system which non-specific interactions.

Using a very comprehensive Chinese firm-level data covering the period of 2000 to 2005, this thesis empirically assesses the determinants and consequences of Foreign Direct Investment (FDI) in China. In particular, the novelty of this research lies in our firm-level analysis which is based on a large sample of firms in 31 host provinces, allowing us to explore the question by distinguishing different modes of FDI inflows. We employ binary-choice models to estimate how institutional quality and pre-acquisition firm heterogeneity affect the probabilities of domestic firms being acquired by foreign investors. We find better institution quality encourages FDI and this effect is stronger in capital-intensive and R&D intensive industries. Moreover, in capital-intensive industries, better institutions reduce the probability of domestic firms being wholly acquired. We also find evidence of 'cherry-picking' which is stronger in capital- and R&D- intensive industries. We then apply a combination of propensity-score matching and difference-in-difference estimation to assess the effect of foreign acquisition on acquired firms with a focus on export performance, productivity and financial indicators. We find significant FDI-induced export lift and finance improvement. However, FDI-induced productivity change is not significant. Finally, we investigate whether location determinants have different effects on attracting greenfield FDI as compared to acquisition FDI. We find the industry cluster pushes greenfield FDI away due to competition effect while attracting acquisition FDI, indicating that procurement opportunities have a strong impact on acquisition FDI.

Incremental Sheet Forming (ISF) is a progressive metal forming process, where the deformation occurs locally around the point of contact between a tool and the metal sheet. The final work-piece is formed cumulatively by the movements of the tool, which is usually attached to a CNC milling machine. The ISF process is dieless in nature and capable of producing different parts of geometries with a universal tool. The tooling cost of ISF can be as low as 5–10% compared to the conventional sheet metal forming processes. On the laboratory scale, the accuracy of the parts created by ISF is between ±1.5 mm and ±3mm. However, in order for ISF to be competitive with a stamping process, an accuracy of below ±1.0 mm and more realistically below ±0.2 mm would be needed. In this work, we first studied the ISF deformation process by a simplified phenomenal linear model and employed a predictive controller to obtain an optimised tool trajectory in the sense of minimising the geometrical deviations between the targeted shape and the shape made by the ISF process. The algorithm is implemented at a rig in Cambridge University and the experimental results demonstrate the ability of the model predictive controller (MPC) strategy. We can achieve the deviation errors around ±0.2 mm for a number of simple geometrical shapes with our controller. The limitations of the underlying linear model for a highly nonlinear problem lead us to study the ISF process by a physics based model. We use the elastoplastic constitutive relation to model the material law and the contact mechanics with Signorini’s type of boundary conditions to model the process, resulting in an infinite dimensional system described by a partial differential equation. We further developed the computational method to solve the proposed mathematical model by using an augmented Lagrangian method in function space and discretising by finite element method. The preliminary results demonstrate the possibility of using this model for optimal controller design.

Turbulence enhanced momentum and energy transport is an important mechanism in shaping the flow and temperature field of low current turbulent SF6 (Sulfur-hexafluoride) arcs burning in a nozzle. It is a factor that largely determines the prediction accuracy of the interruption capability of high voltage circuit breakers. Previous study [81] has shown that for SF6 arcs the parameters in the Prandtl mixing length model and the two equation k-ε model must be adjusted to bring agreement between prediction and measurement. The experimental observation [109] of steep temperature or density gradient exists at the arc edge, where turbulence is usually strongest. The density gradient can be regarded as a result of temperature gradient when the pressure difference across the low current arc column is small. In previous studies of turbulence models, the effects of large density or temperature gradient have not been considered. In the present work the k-ε model is modified to take into account the effect of the presence of steep local temperature gradient. The model is first applied to the steady state SF6 nozzle arcs in the current range from 100 A to 1800 A. The performance of the modified turbulence model is assessed by a comparison of the predicted and measured radial temperature profiles at different currents and its behaviours with another two most commonly used turbulence models, the Prandtl mixing length model and the k-ε model. The relevant turbulence parameters of the Prandtl mixing length model are adjusted according to the different nozzle shapes with different values and it has been found that its applicability is limited. The modified k-ε model, which is modified to take into account the effect of large temperature gradient with all default coefficients, can make reasonable prediction for turbulent arcs in the Aachen nozzle [67, 108] under direct current conditions. The model is then applied to the transient nozzle arcs in a GE nozzle [86] and the Campbell nozzle [85]. Finally, a real puffer-type circuit breaker of 252 kV has been used to verify this model. The predicted arc voltage and pressure agree reasonably well with the measurements at both high and low current levels, justifying the applicability of the modified k-ε turbulence model. The auto-expansion circuit breaker is a relatively new interruption technique, which creates the required fast gas flow at current zero using the energy dissipated by the arc itself. A design study has been carried out for a prototype 245 kV auto-expansion circuit breaker at 50 Hz, in order to investigate the influence of key design parameters in terms of arcing conditions at the current zero phase and the critical RRRV (Rate of Rise of Recovery Voltage). Auxiliary nozzle with different lengths, and the severity of leakage from the expansion volume have been implemented for testing the influence of design parameters in an auto-expansion circuit breaker. PC-based arc modelling taking account the effect of nozzle ablation and the mixing process of PTFE vapour with SF6 has been made for auxiliary nozzle investigation. For the effect of leakage, various sizes of a leakage hole are specified on the valve of the expansion volume. The critical RRRV values for the Ref. Case and the its modifications are used for comparison of its interruption capability in order to estimate the influence of these key design parameters. The solution of all of the equations in the arc models is based on a commercial computational fluid dynamics package, PHOENICS. PHOENICS has been extensively used at the University of Liverpool to model the arc behaviours since 1992. Before using PHOENICS to simulate the arc behaviour in this thesis some conditions need to be resolved. These are related with the choice of turbulence model, the computational domain size for electric field, and the influence of the Lorentz force. The differential models for reported works in the thesis is implemented into PHOENICS version 3.6.1. All boundary conditions which are treated as sources terms are discussed in Section 2.3.

The present thesis is on the error estimates of different energy based quasicontinuum (QC) methods, which are a class of computational methods for the coupling of atomistic and continuum models for micro- or nano-scale materials. The thesis consists of two parts. The first part considers the a priori error estimates of three energy based QC methods. The second part deals with the a posteriori error estimates of a specific energy based QC method which was recently developed. In the first part, we develop a unified framework for the a priori error estimates and present a new and simpler proof based on negative-norm estimates, which essentially extends previous results. In the second part, we establish the a posteriori error estimates for the newly developed energy based QC method for an energy norm and for the total energy. The analysis is based on a posteriori residual and stability estimates. Adaptive mesh refinement algorithms based on these error estimators are formulated. In both parts, numerical experiments are presented to illustrate the results of our analysis and indicate the optimal convergence rates. The thesis is accompanied by a thorough introduction to the development of the QC methods and its numerical analysis, as well as an outlook of the future work in the conclusion.

Cathodic electrodeposition (CELD) is achieved via hydrolysis of metal ions by electrogenerated base to form metal oxideihydroxide films on a cathodic substrate. Hydroxides and peroxides can then be converted to oxides by thermal treatment. In this study, Ti02 thin films (both rutile and anatase phases) and cobalt-doped anatase films were successfully produced through this method. These materials have presented applications in electronic and magnetic devices, such as piezo-ceramics as well as in catalysis. The CELD technology and the characterization of these thin films are described in detail in this thesis. The various parameters (deposition time, current density and annealing temperature etc.) that affect the characteristics ofTi02 films deposited on Pt and Ti substrates have been explored. Focus ion beam imaging (FIB) and scanning electron microscopy (SEM) analysis show that the thickness of the film increases as the deposition time increases. Applying current density greater than 30 mA'cm-2 results in the film having a porous structure, however, little difference between films was observed when the current density was 20 mA'cm-2 or less. XRD data gave an indication that the as-deposited films were amorphous; after annealing at elevated temperatures (400°C ~ 1000°C) anatase and rutile phases were formed successfully. Samples were thermally treated under three different atmospheres: air, argon and argon/hydrogen (10% hydrogen). Different characteristics were observed after annealing. SEM and atomic force microscopy (AFM) show that the particle size increased after annealing in argon and argon/hydrogen. Preferred orientation ofthe films annealed in different atmospheres was observed and further investigated using high temperature in-situ XRD. Ti1-xCOx02-o films were successfully prepared on Ti and Si substrates. When the annealing temperature was above 600°C a CoTi03 phase was detected in the film, whilst maintaining the anneal temperature below 600°C resulted in only anatase peaks ((101) and (200)) being observed. The films annealed at 400°C show room-temperature ferromagnetism as determined by vibrating sample magnetometry, and the magnetization per unit volume was of the right order of magnitude (0.2-0.6JlB/CO) for dilute ferromagnetic oxide thin films. X-ray absorption spectroscopy studies showed that the cobalt was present as Co2+ and the XRD data were consistent with cobalt substituted anatase lattice as the lattice parameter increased from 9.0080(2) to 9.4780 (3)

Conflicts between traffic participants may arise when their spatio-temporal trajectories come sufficiently close. Without timely detection and appropriate management, these conflicts may lead to safety hazards and compromise traffic efficiency. Emerging technologies in vehicular automation and vehicle-to-everything (V2X) communication opened up new opportunities to resolve conflicts between vehicles in a cooperative manner. On the other hand, a mixed-autonomy environment consisting of vehicles with different automation and cooperation capabilities is expected to bring additional challenges to conflict resolution over the next few decades. In this dissertation we construct a framework of conflict analysis to detect, manage, and resolve conflicts arising in cooperative maneuvers between vehicles at different levels of automation and cooperation. Two different classes of cooperation, enabled by V2X communication, are considered as means to prevent conflicts: status sharing and intent sharing. Status sharing allows vehicles to exchange their instantaneous states (e.g., current velocity and position), whereas intent sharing enables further information exchange regarding the intended future motion of vehicles (e.g., velocity and acceleration bounds). In conflict analysis, we interpret the dynamical information encoded in status and intent messages by means of conflict charts, where the state space is partitioned into the so called no-conflict, uncertain, and conflict domains. This allows for efficient decision making and controller design. We first establish the concept of conflict analysis to prevent conflicts between two vehicles. Conflict-free maneuvering strategies are developed and communication requirements for the existence of such strategies are determined. We then extend the established conflict analysis framework to study conflicts between multiple vehicles, while considering two types of time delays, one in vehicle dynamics and the other in V2X communication. Using reachability theory, conflict analysis allows us to examine the merits of communication in conflict prevention in the presence of delays. It is revealed that receiving status information can facilitate conflict-free maneuvers, but time delays can compromise such opportunities. It is also shown that receiving intent information compensates the effects of delays, removes unnecessary conservatism from decision making, and improves the efficiency of controllers of connected vehicles. We design a goal-oriented controller for connected automated vehicles to pursue conflict-free maneuvers, and demonstrate the framework using simulations with real highway data. Our analysis is brought to practice by generalizing the representation of vehicles' motion intent from a dynamical systems viewpoint. This enables us to extend conflict analysis by incorporating intent information. Such an extension is used to assist the decision-making of intent-receiving vehicles, and can be tailored to both automated and human-driven cases. We create intent messages using commercially available V2X devices, and experimentally demonstrate the benefits of sharing intent in cooperative maneuvering. Furthermore, we test intent messages on public highways and evaluate the performance in terms of packet delivery ratio. The collected data are fed into simulations to investigate the effects of intent transmission conditions (e.g., sending frequency, intent horizon, and packet drops) on conflict resolution. In summary, this dissertation presents state-of-the-art results on V2X-based conflict management in cooperative maneuvering under mixed autonomy. The novel framework of conflict analysis provides a rigorous yet scalable means to enhance traffic safety and efficiency. This dissertation is among the very first efforts to systematically study the communication impact on conflicts in mixed traffic. Our theoretical study and experimental evaluation on intent sharing cooperation are expected to benefit the on-going standardization and future real-world deployment.

Wax precipitation at low temperatures can pose significant flow assurance challenges during offshore transportation of waxy crude oils. The sharp increase of viscosity due to wax precipitation increases the pressure drop and thus raises the capital and operating cost of transportation. Conventional methods of lowering the viscosity of waxy oils include adding chemicals or externally heating the pipeline, both of which are energy-costly and carbon-intensive. Therefore, there is a need to develop economic and eco-friendly solutions to improve the cold mobility of waxy oils. Previous studies have demonstrated that the electrical treatment of waxy crude oil can significantly lower its viscosity at a relatively low energy cost. Previous research mainly focused on demonstrating the electrorheological behaviors of waxy crude oils, and it has been believed that charged particles in the crude oils, such as resins and asphaltenes, play a critical role in reducing the viscosity of waxy crude oils under electric fields. It remains unknown the performance of electrical treatment on waxy oils in the absence of resins and asphaltenes. To fill in this gap, in this research, the electrorheological responses of waxy model oil systems consisting of mineral oil, decane, and paraffin wax were investigated by a DHR-20 rheometer equipped with an Electro-Rheology accessory. The sample’s viscosity was monitored in three consecutive 10-minute stages: before, during, and after the application of DC electrical fields ranging from 0 to 3.5 kV/mm. Significant viscosity reductions were observed in nearly all model systems, and the maximum viscosity reduction of 82.9% was obtained at 22 °C by applying a 3.5 kV/mm electric field. The magnitude of viscosity reduction depends on several factors, including electric field strength, temperature, and the amount of precipitated wax. Furthermore, the addition of 1wt% n-decane was found to significantly enhance the effectiveness of the electric treatment, increasing the viscosity reduction by nearly 40%. These findings challenge the widely accepted theories in the literature that resins and asphaltene play a critical role in reducing the viscosity of waxy crude oil by electrical treatments and could potentially aid future research in better understanding the underlying mechanisms behind the negative electric effects on the viscosity of waxy crude oils.

Trichloroethene (TCE) is one of the most commonly found hazardous compounds at Superfund sites, especially in groundwater. Its volatility and toxicity pose a threat to drinking water safety and human health. In the past decades, research on the fate of TCE in the environment has shifted to contamination of low-permeability formations, for example fractured bedrock aquifers. TCE back-diffusion from low permeability zones and management of persistent TCE groundwater plumes caused by this long-term source zone pose major challenges for remediation. Monitored natural attenuation (MNA) is a cost-effective remediation strategy that has gradually gained acceptance by regulators. Compared to extensive active remediation of persistent TCE plumes, MNA is more attractive for its cost-effectiveness. However, acceptance of MNA as a remediation strategy depends on adequate documentation of in situ TCE degradation at meaningful rates. Collecting lines of evidence in support of TCE natural degradation is an essential component of MNA. In this study, two lines of evidence were collected for three Department of Defense sites overlain with fractured bedrock that are experiencing TCE back-diffusion. The first type of evidence involved monitoring groundwater for dissolved gas products associated with abiotic degradation (i.e., acetylene, ethene, and ethane) using a novel passive vapor diffusion (PVD) sampler. The other line of evidence was based on the use of intact rock core microcosms to estimate TCE degradation rate constants. This is the first study to employ the use of 14C-labeled TCE in intact rock core microcosms. Estimating the TCE degradation rate constants was accomplished with numerical modeling.

Directed Acyclic Graphs (DAGs) are a powerful tool to model the network of dependencies among variables. They provide a basis for causal discovery, and have been widely used in many fields, especially biology. Unfortunately, structure learning is quite non-trivial for DAG. One major difficulty is that some DAGs are unidentifiable with observational data only, and undirected edges cannot be resolved to directed edges.The opportunity to apply interventions motivates interest in the smaller interventional Markov equivalence class. In this dissertation, we discuss how to modify the classic PC algorithm for causal discovery so that it can be used safely on interventional data. We introduce invariance relations on conditional distributions with different intervention targets that provide a powerful rule for edge orientation. There are several advantages of this rule: first, it does not require the Gaussian distribution assumption, instead a general structural equation model (SEM) of DAG is sufficient; second, it works for both (structural) intervention and soft intervention. Finally, we can merge some data blocks with different interventions for edge orientation.A new constraint-based method is proposed to recover the interventional essential graph from the CPDAG (or called as observational essential graph) based on the invariance rule. We also establish consistency guarantees for both an interventional PC and an edge orientation algorithm under a sparse high-dimensional setting. Such high-dimensional consistency results are rarely seen in this area. It is also worthwhile to emphasize that the constraints on the family of interventions throughout this dissertation are mild. Finally, simulations are used to show the effectiveness of our method.

Dust problems raise significant concerns in planetary surface exploration. The unusual behavior of the dust particles that surround the vehicle after engine cutoff has the potential to have more of an influence on surface systems than the high velocity lunar rocket plume ejecta in the landing process. A prevailing hypothesis attributes the levitation and transport of dust particles on the surface of airless bodies to the electrostatic effects and electric field. However, there is no accurate model considering the inter-particle electrostatic interactions, especially when the particles are charged by plume. This dissertation aims to understand the behavior of charged lunar regolith with a discrete element method (DEM) approach focusing on the inter-particle interactions and contact charge transfer. To accomplish this, the grain dynamics is coupled with mechanical and electrical particle interactions, and both short-range and long-range interactions between particles are incorporated. A tribo-charging model based on instantaneous collisions is adopted and validated by simulation and experimental data. Sensitivity analysis is conducted to quantify the effects of initial charge, tribo-charging, and E-field on transport of lunar dust. DEM simulations are then performed for a near realistic lunar environment that show the differences of position and velocity distributions between charged particles and uncharged particles. The results indicate that the charged dust particles have higher dispersion and wider distribution of velocity due to the electrostatic effects. This provides a possible explanation for the phenomena of the approximately 30 s dust lofting following Apollo Lunar Module landing. It is shown that tribo-charging has a more considerable effect on the dynamics of charged particles with a large amount of charge, while the change of E-field does not significantly affect the results. Furthermore, superquadrics and multi-sphere approximations are introduced as two approaches to aspherical geometry to accomplish high-fidelity simulation of lunar dust in the future.

Woodchip bioreactors are used to remove nutrients from the subsurface drainage.However, the nitrogen removal performance and efficiency of woodchips are limited by low temperature and limited availability of liable carbon. Bioaugmentation (i.e., adding cold-adapted denitrifying microbes) and biostimulation (i.e., adding substrates to enhance the activities of indigenous microbial populations) are potential approaches to enhance nitrate removal of woodchip bioreactors at cold conditions, but their effectiveness is still unclear. My thesis research was done to clarify the effects of bioaugmentation and biostimulation on the microbial communities in woodchip bioreactors. I also examined how microbial community change influenced the overall nitrate removal. Previously isolated cold-adapted denitrifying bacteria Cellulomonas sp. strain WB94 and Microvirgula sp. strain BE2.4 were used in this study. These strains were obtained from woodchip bioreactors and were verified to reduce nitrate at cold temperatures. Based on the whole genome analysis, Microvirgula sp. strain BE2.4 has a complete set of denitrification genes, while Cellulomonas sp. strain WB94 has genes for cellulose degradation. These two strains were grown in the lab condition and inoculated back into the woodchip bioreactors located at Willmar, MN (i.e., bioaugmentation). In addition, acetate was added into the woodchip bioreactors as a liable carbon source to promote denitrification (i.e., biostimulation). Woodchip samples were taken before and after the bioaugmentation and biostimulation treatments to examine the changes in the abundance of inoculated strains and the impact of the two treatments on the microbial communities in woodchip bioreactors. Strain-specific TaqMan probe quantitative PCR assays were designed to quantify the abundance of inoculated strains. A high-throughput Nitrogen v Cycle Evaluation (NiCE) chip was also used to quantify various N cycle-related genes in many samples. Furthermore, microbial communities in the woodchip bioreactors were analyzed by sequencing the V4 region of the 16S rRNA gene on the Illumina MiSeq platform. TaqMan probe qPCR results showed that the abundance of inoculant Cellulomonas sp. strain WB94 increased in all the treatment and control bioreactors throughout the sampling period (p < 0.05), suggesting that genera Cellulomonas plays a key role in the cellulose degradation process inside aged woodchip bioreactors. The abundance of inoculant Microvirgula sp. strain BE2.4 tended to increase in the bioaugmentation bioreactors, although this increase was not statistically significant, most likely due to considerable variation between samples. 16S rRNA gene amplicon sequencing results showed that the treatments account for 4.07% of the difference in the microbial community between samples. NiCE chip results showed that the abundance of amoA, hao/hdh, and nosZ can be used to predict the nitrate removal rate of woodchip bioreactors. In addition, there was a positive relationship between the abundance of inoculant Microvirgula sp. strain BE2.4 and the abundance of denitrification gene norB and nosZ in the woodchip bioreactors. These results showed that bioaugmentation and biostimulation treatments could change the microbial communities in the woodchip bioreactors and increase the abundance of denitrifiers to optimize the denitrification efficiency of the bioreactors.

Abstract: Energy is one of the most indispensable ingredients in modern economies and is a critical cornerstone for the development of human society. In contrast to carbon-intensive legacy fossil fuels, low-carbon renewable energy sources (such as solar and wind) provide a significant opportunity to alleviate carbon emissions and global anthropogenic climate change. Due to the intermittent nature of solar and wind energy, the need for energy storage to complement these vast but fluctional sources of wind and solar energy is pressing. Redox flow batteries (RFBs) are promising thanks to their inherent decoupling of stored chemical energy and tunable power density, as well as their low cost, safe operation, and long lifetimes. Traditional inorganic RFBs, such as all-vanadium RFBs, have been studied for over three decades and have undergone successful commercialization. These batteries are, however, subject to problematic issues related to their chemistry, including corrosivity (e.g., sulfuric acid is the solvent), cost (ca. $27/kg for vanadium (V) oxide raw material and $500/m2 for Nafion membranes), parasitic reactions, and crossover of electrolytes that reduces efficiency. RFBs based on organic electrolytes may be promising alternatives for the next-generation of aqueous RFBs due to the tunability of their chemical and physical properties. To achieve high performance aqueous flow batteries, much development is needed as well as detailed fundamental studies of the electrochemical properties of these redox electrolytes. This thesis focuses on developing new organic materials and improved electrochemical methods for the next generations of aqueous RFBs for storage of low-carbon energy. The thesis can be divided into two parts. In the first part of the thesis, mathematical modeling was applied to simulate the electrochemical behavior of electrochemically reversible, quasi-reversible, and irreversible systems by using different electrochemical techniques. The advantages and limitations of these electrochemical methods to acquire kinetics parameters were analyzed and discussed, and their limitations addressed and reconsidered. The result of this work was a new method and protocols to obtain electrochemical rate constants and diffusion coefficients for both reduced and oxidized species. The effects of heterogeneous rate constants of redox compounds on the performance of the flow batteries also were simulated and evaluated. In the second part, a water-soluble octahedral bis(imino)pyridine cobalt complex was synthesized. Due to the introduction of carboxylic groups to the bis(imino)pyridine ligand periphery, the complex is water soluble, with two redox couples within the water splitting window. Its electrochemical kinetics, pH-dependent cyclic voltammetric behavior, and solubility in the water solution were investigated thoroughly. Symmetric aqueous RFBs with the complex acting as both catholyte and anolyte were fabricated, and they were found to have high capacity retention and good Coulombic efficiencies over 100 cycles. Upon completion of this work on the cobalt complex, the project was extended to a series of phenazine derivatives with different numbers of sulfonated terminated short carbon chains that were designed and prepared. The redox potentials, solubility, and stability of the phenazine moieties are modulated through the tailoring of the number and position of the functional groups. The electrochemical properties and the performance of full cell aqueous RFBs also were investigated.

We present an incremental Lagrangian framework based on meshfree methods, the Hot Optimal Transportation Meshfree (HOTM) method, for a robust and efficient solution of the dynamic response of materials in extreme multi-physics problems, possibly involving strongly coupled thermomechanical conditions, extremely large deformation, phase transition, and multi-phase mixing. The HOTM method combines the Optimal Transportation Meshfree (OTM) method and the variational thermomechanical constitutive updates. The variational structure of a dynamic system with general internal dissipative mechanisms is discretized in time by applying the Optimal Transportation theory, while the material points sampling approach and Local Maximum Entropy approximation are introduced for spatial discretization. Meanwhile, a phase-aware constitutive model is proposed to describe the material behavior with general dissipation mechanisms, which involves elasticity, plasticity, viscosity, and phase transition. The fully discretized mechanical balance equations and thermal balance equations are solved using an operator splitting algorithm to predict the deformation, temperature, and internal state variables of the material. The convergence of the computational framework is studied in a three-dimensional transient heat conduction problem, while the accuracy of the HOTM method is validated in the example of upsetting a metallic billet. The scope and robustness of the HOTM method are demonstrated in the application of hot pressing manufacturing processes of resin-based friction composites and an emerging additive manufacturing process called laser cladding technology.

This study has been undertaken to gain a new understanding of the relationship between housing density and liveability. Through a critical examination of various concepts of density, a holistic theoretical framework of density has been proposed and tested via a case study, that is, the housing history of Shanghai between 1843 and 1949 is analysed and interpreted from a density perspective. There are numerous misconceptions about density as revealed in the surveyed literature of architecture and urban planning. High density, as a method of measuring efficiency and the sustainability of urban environment, has become the dominant goal in urban development according to the modern mindset. Such a mindset has led to misconceptions about density, such as understanding it in a singular, quantitative and linear way. Perceptions that human beings have in relation to density are ignored, making density difficult to use as an effective reference to guide the shaping of liveable urban environments. It is therefore necessary to propose a holistic theoretical framework of density that integrates physical density and perceived density. From the perspective of density, Shanghai's urban housing history is a story of western urban planning and architectural concepts that have been grafted and adapted and then finally developed into a unique urban environment. Shanghai's distinctive topographic and socio-cultural context is an important background behind the development of a diverse and integrated living environment. This study explores ways of shaping urban fabric and housing through re-enacting the living environment of Shanghai from 1843 to 1949. The study includes two steps. Firstly, the concepts of physical density and perceived density are respectively correlated to parti and poché used in the École des Beaux-Arts’ architectural education to propose a new theoretical framework of density. Secondly, physical and social conditions of the living environment in Shanghai between 1843 and 1949 are re-enacted from the macro to the micro scale following the structure of the street-system, street-blocks and block-plans. Corresponding to these three levels, the findings from the case studies consist of three parts. First, the street system, inherited from the spatial morphology of the agricultural era, formed appropriately sized blocks that balanced the vitality of the streets and the stability within the blocks. Second, the remarkable diversity of urban plots converted from pre-divided agricultural land, facilitated the appearance of mixed uses and varied building forms within a single block to meet the needs of different groups of residents. Finally, different forms of boundaries were used as effective architectural strategies to purposefully manipulate perceived density and thus improved the liveability of urban environments. These findings describe the fitting relationship between living environment and ways of living so that the influence of density on liveability is elucidated. The findings of this study reveal that the density of a liveable environment is not an absolute value. Liveability is closely related to both physical density and how it is perceived. The housing history of Shanghai from 1843 to1949 shows that residents of certain quarters of Shanghai during that period developed a fitting relationship between their ways of living and the living environment within a specific socio-cultural context. This relationship and its vernacular and agricultural roots are an important reference for the purposeful shaping of perceived density and consequently the creation of a liveable environment. This thesis makes contributions to both theoretical and practical properties of density. The theoretical framework integrating physical and perceived density provides a new perspective for urban housing history studies and can be used as an effective reference for achieving a balance between economic efficiency and liveability in contemporary urban design and administration.

Millimeter-Wave (mmWave) Integrated Circuit (IC) design has become a promising research topic since last decade. Millimeter-Wave signals (30GHz to 300GHz) benefit from ultra-high bandwidth and unique physical attributes. With the portability brought by IC techniques, mm-wave chips have enabled applications such as ultra-high-speed (5G/6G) communications, mobile satellite communications, Internet-of-Things (IoT) sensors, ultra-high-resolution radar and various kinds of dieletric, biomedical and chemical sensors. However, with stringent power budget of portable devices and the power-hungry attribute of mmWave circuits, low-power and low-noise on-chip mmWave signal generation and radar design are faced with great challenges.In the first part of this dissertation, a new mmWave frequency synthesizer structure is proposed. Based on Sub-Sampling Phase-Locked Loop (SSPLL) technique, the generated signal achieves low in-band phase-noise. With the proposed dividerless frequency acquisition technique based on a Sub-Sampling Lock Detector (SSLD) and on-chip intermediate-frequency PLL (IF-PLL), the SSPLL can automatically detect its lock status and lock to the correct target frequency without using power-hungry mmWave Injection-Locking Frequency Dividers (ILFD). To verify the proposed system, a prototype 40.5GHz SSPLL chip has been taped out in 65nm CMOS. Due to the relatively low-frequency operation and moderate noise requirement of IF-PLL, as well as the low-power SSLD, the proposed system achieves low power consumption and jitter simultaneously. The measured results show an 8.8mW power consumption and 228fs RMS jitter with in-band and out-band phase noise of -96.6dBc/Hz at 1MHz offset and -106.9dBc/Hz at 10MHz offset, respectively. Another critical issue of charge pump (CP) current mismatch and its exclusive effects on SSPLL are presented in this dissertation. Transistor’s channel-length-modulation (CLM) effect induces SSPLL loop gain distortion and decreases VCO control voltage (Vctrl) locking range (LR). A feedback based compensation method, which is the first-published solution to SSPLL CP mismatch, is then proposed. In a prototype mmWave SSPLL with the proposed compensated CP, the CLM effect is cancelled and Vctrl LR is extended from 0.50V to 0.75V under a 1V supply, without degrading SSPLL noise performance much. As a result of the more efficient use of Vctrl range, VCO capacitor bank setup number is reduced from 10 to 7 to cover the same 10% total tuning range. The compensation circuitry consumes only 0.36mW power. The prototype 40.5GHz SSPLL consumes only 9.5mW power with 192fs RMS jitter. Radar sensors with ultra-high range resolutions have great potential in non-contact sensing of human vital signs, biomedical signals, material thickness and mechanical vibration, and in imaging. With short wavelengths for high resolution and relatively simple structure, mmWave Doppler radar has become a competitive candidate in various displacement-sensing applications. However, issues like detection nulls, nonlinear gain and quadrature signal paths mismatch limit the performance of mmWave Doppler radar. In the last part of this dissertation, a novel system structure of Doppler radar front end is proposed utilizing the intrinsic low added in-band noise feature of SSPLL and a proposed quadrature-less demodulation method. A prototype 110mW 39GHz Doppler radar front end in 65nm CMOS for displacement and vibration sensing is presented. Sub-sampling PLLs (SSPLL) generate single-tone radiated signal. A proposed phase demodulator (PDM) uses coherent IF demodulation to convert displacement to a DC/baseband signal with constant gain. Detection nulls in conventional Doppler radars are eliminated without using quadrature demodulation. The prototype radar achieves 4µm static and 77nm vibrational (at 10KHz) range resolutions.

Development of light-driven funcational materials capable of dynamic and reversible tunable properties is gaining broad attention. Towards this endeavor, I have made efforts to design, synthesize, and characterize new light-driven chiral molecular switches, which are capable to induce tunable self-assembled helical superstructures in liquid crystals. The induced helical superstructures can be tuned by various stimuli, such as light, electric field, magnetic field, and mechanical force. Among them, light is of particular importance as it possesses precise, spatial, and non-invasive advantages.This dissertation discusses the successful synthesis of photoresponsive chiral molecular switches, which have been applied in diverse light-tunable self-assembled helical superstructures.

My dissertation draws upon the novel-to-the-field rice theory to study how subnational cultural heterogeneity formulated in ancient agricultural society affects business decisions and firm performance in merge and acquisition activities. Through a series of three related papers, my dissertation contributes to the literature on experiential learning, post-acquisition integration and subnational cultural interactions. Each chapter addresses unique gaps in the extant literature and examines critical challenges to the research of the cultural impacts in the merge and acquisition.

Previous studies have shown that certain flax varieties are especially prone to genomic destabilization by the external growing environment. The best characterized variety that responds to this environmental stress is the fiber flax variety Stormont cirus, which is subsequently referred to Pl. Bethune is an oil seed variety, which appears to be genomically stable irrespective of the growth environment. To elucidate the genetic control of this phenomenon, a cross was made between Pl and Bethune. The F1 generation from this cross (Bethune x Pl) was grown in a non-inducing environment and appeared to be stable under this environment. However, when the F1 generation was grown under an inducing environment, then genomic variation was observed which is consistent with the character of inducibility under the stress of the external growing environment being a dominant characteristic. When F2 individuals from these non-induced F1’s were grown under inducing conditions then, using the amplification of LIS-1 as the marker for inducibility, some individuals showed inducibility and some were stable. Scoring many loci in these induced F2’s showed that many were inherited in the expected Mendelian pattern, but some were inherited anomalously. In general, the data indicated that there was an overabundance of Bethune parental alleles, where the allele in Bethune was the same as that in induced progeny from Pl. The alleles were characterized by PCR so individual loci were scored independently. Subsequently, whole genome sequencing was done for a set of DNAs isolated from these F2’s. A 2Mb region of Chromosome 14 was selected because it is a potential region which contains multiple sections that respond to the growth environment. The rDNA, which is a quantitative polymorphism associated with the induction of genomic changes, was also assessed to observe the data for a different chromosome. Several potential blocks and some SNPs have been determined as the border of responsive regions. The rDNA data shows a different extent of responsiveness in F2 individuals and indicates that the induction may be under the control of 2 genes.

Emerging connected and automated vehicle (CAV) technologies are improving vehicle safety and energy efficiency to the next level and creating unprecedented opportunities and challenges for the control and optimization of the vehicle systems. While previous studies have been focusing on improving the fuel efficiency via powertrain optimizations, vehicle thermal management and its interaction with powertrain control in hot and cold weather conditions have not been fully explored. For light-duty vehicles, the power used by the climate control system usually represents the most significant thermal load. It has been shown that the thermal load imposed by the climate control system may lead to dramatic vehicle range reduction, especially for the vehicles with electrified powertrains. Besides its noticeable impact on vehicle range reduction, the performance of the climate control system also has a direct influence on occupant comfort and customer satisfaction. Aiming at reducing the energy consumption and improving the occupant thermal comfort (OTC) level for the automotive climate control system, this dissertation takes air conditioning (A/C) system as an example and is dedicated to developing practical A/C management strategies for electrified vehicles. In particular, the proposed strategies leverage the predictive information enabled by the CAV technologies such as the traffic and weather predictions. There are three novel MPC-based A/C management strategies developed in this dissertation, the hierarchical optimization, the precision cooling strategy (PCS), and the combined energy and comfort optimization (CECO). They can be differentiated by their OTC assumptions, robustness considerations, and implementation complexities on the testing vehicle. In the hierarchical optimization, a two-layer hierarchical MPC (H-MPC) scheme is exploited for potential integration between the A/C and the powertrain systems of an HEV. This hierarchical structure handles the timescale difference between power and thermal systems as well as the uncertainties associated with long prediction horizon. Comprehensive simulation results over different driving cycles have demonstrated the energy saving potentials of efficient A/C energy management, which is attributes to leveraging the vehicle speed sensitivity of the A/C system efficiency. In terms of the comfort metric, the average cabin air temperature is applied. In contrast to this hierarchical optimization, PCS and CECO utilize the simpler single-layer MPC structure assuming accurate predictive information. They are focusing on formulating more practical OTC metrics and the implementation on the testing vehicle. Specifically, the PCS renders the simplest control-oriented model structure and its energy benefits are validated based on an industrial-level A/C system model. The proposed PCS exploits a more practical comfort metric, DACP, which directly motivates the design of an off-line eco-cooling strategy, which coordinates the A/C operation with respect to the vehicle speed. Vehicle-level energy saving is confirmed according to repeatable vehicle experiments. Finally, the CECO strategy considers a comprehensive OTC model, PMV, and combines the energy and comfort optimizations simultaneously. Further energy saving and OTC improvement can be achieved by explicitly leveraging both traffic and weather predictive information.

Freight transportation represents about 9.5% of GDP in the U.S., it is responsible for about 8% of greenhouse gas emissions and supports the import and export of about 3.6 trillion in international trade. It is therefore important that the national freight transportation system is designed and operated efficiently. Hence, this dissertation develops a mathematical model to estimate international and domestic freight flows across the ocean, rail and truck modes, which can be used to study the impacts of changes in our infrastructure, as well as the imposition of new user fees and changes in operating policies. The model integrates a user equilibrium-based logit argument for path selection with a system-optimal argument for rail network operations. This leads to the development of a unique solution procedure that is demonstrated in a large-scale analysis focused on all intercity freight and U.S export/import containerized freight. The model results are compared with the reported flow volumes. The model is applied to two case studies: (1) a disruption of the seaports of Los Angeles and Long Beach (LA and LB) similar to the impacts that would be felt in an earthquake; and (2) implementation of new user fees at the California ports.

Corin is a transmembrane serine protease essential for salt-water balance and normal blood pressure. Human corin has 19 N-glycosylation sites. In this study, we investigated the role of N-glycosylation in corin biosynthesis.First, we investigated the role of N-glycosylation in corin cell surface expression, zymogen activation and ectodomain shedding. We mutated each of the 19 N-glycosylation sites and characterized the corin mutants in functional studies. Our results show that N-glycosylation at Asn-80 and -231 protected corin from ectodomain shedding. N-glycosylation at Asn-697 and -1022 promoted corin cell surface expression and zymogen activation. Next, we analyzed the functional importance of N-glycosylation in the corin protease domain. We generated corin mutants that lacked the transmembrane domain or extracellular domains in the pro-peptide region and chimeric corin mutants containing the protease domain from a different serine protease. We also extended our study to include prothrombin, factor VII and enterokinase. Our results show that the function of N-glycosylation in the protease domain in promoting corin cell surface expression is independent of the pro-peptide domains and that N-glycosylation in the protease domain also promoted the secretion of prothrombin and factor VII and the cell surface expression of enterokinase. Finally, we performed proteomic and cellular studies to understand how N-glycans in the protease domain promote corin cell membrane targeting. Our results show that N-glycans in the protease domain facilitated corin trafficking in the endoplasmic reticulum (ER). Moreover, we found that corin proteins lacking the N-glycosylation site in the protease domain were bound to calnexin and BiP in the ER. These data indicate that N-glycans in the protease domain of corin are important in calnexin-assisted protein folding and ER exiting. We also show that such a mechanism may apply to the function of N-glycans in other trypsin-like serine proteases such as prothrombin, factor VII and enterokinase.Together, our results show that N-glycans at different sites of corin protein play distinct roles in regulating corin folding, intracellular trafficking, cell surface expression, zymogen activation and ectodomain shedding. Our results also suggest that N-glycosylation may have similar roles in the protein synthesis and posttranslational modifications of other trypsin-like serine proteases.

In a multi-component chocolate product, oil migration, from high oil content filling into the chocolate is one of the major contributors to quality loss. Five different cocoa butter samples were used to model and study the effects of chemical composition and processing conditions on oil migration. Samples were crystalized under two different processing conditions. Control samples were crystalized under 0 shear rate and 0.5 °C/min cooling rate. Processed samples were crystalized under 250s-1 shear rate and 4.5 °C/min cooling rate. Crystalized cocoa butter samples were placed in contact with a cream as a source of liquid oil. Using magnetic resonance imaging, the movements of liquid oil into samples were investigated. The sample oil diffusivity was analyzed based on the Fickian diffusion model. Slightly different chemical composition affected cocoa butter’s melting point, solid fat content, microstructure, and resulted in different oil migration rate in the samples from five different origins. Additionally, processing conditions significantly retarded the oil migration rate in cocoa butter system. However, identical trends observed in control and processed samples indicated that different processing conditions would not eliminate the effects of chemical composition in cocoa butter on oil migration kinetics.Overall, minor differences in chemical composition of cocoa butters from different origins affect the oil diffusivity. Processing conditions can help slow down the rate of oil migration in cocoa butter system. However, it would not overcome the effects of chemical composition on oil migration kinetics.

With the rapid development of mobile and implantable devices, the wireless power transfer (WPT) technology has become increasingly attractive because it frees numerous electronic systems from power cords or batteries. Recently, the WPT method based on the magnetic resonant coupling has gained popularity both in research and applications. This dissertation contributes to the magnetic resonant WPT system design by addressing three important problems. The first problem deals with the design of multiple-resonator systems. In order to power objects over a longer distance, a multiple-resonator system is usually needed. However, most existing multiple-resonator systems are designed experimentally with a strict requirement on the position of the resonators. We propose to optimize multiple-resonator systems by investigating the transfer function from the transmitter to the receiver. An equivalent circuit model is developed to maximize the power output. This method is then utilized to find the optimal position for the relay resonator in a three-resonator wireless power transfer system. The second problem is to power a device which is mobile within a certain field. The Biot-Savart law and a concentric model of a spiral coil are utilized to simulate the magnetic field distribution of a multiple-transmitter WPT platform. The vertical component of the magnetic field of the coil is optimized to achieve an evenly distributed magnetic field over the field. As a result, a position-free powering of mobile sensors or devices is achieved. The third problem deals with integration of wireless power transfer and wireless data communication. This problem is especially importation in implanted medical sensors where power must be delivered to the implants and measured data must be transmitted to the outside of the human body. Currently, most implementations of power and communication systems utilize a separated data channel, which requires not only substantial power consumption but also a high complexity of the implanted circuit. In this work, a unified data and power channel is developed in which data are processed by an asynchronous sigma-delta pulse conversion. The resulting pulses are transmitted using load modulation.

The focus of this thesis is on the multi-agent rendezvous problem where the rendezvous location has the total squared shortest distance to certain regions. Three algorithmsare experimentally implemented under an undirected communication topology. Simulation plots and experimental results are demonstrated on a multi-robot platform to validate the proposed algorithms. First, an implementation of the distributed subgradient shortest-distance rendezvous algorithm is implemented. Second, an alternative distributed shortest-distance rendezvous algorithm which introduces a kind of diminishing step sizes is validated. Third, an algorithm with employment of two internal states of the dynamic averaging estimator is implemented. This thesis illustrates the three algorithms by presenting simulation plots in Matlab, robots’ moving trajectories in the multi-robot platform, and plots of the shortest distance performance function.

The relocation decisions by individual households collectively shape urban areas; hence we use the American Household Survey to empirically study these mobility decisions. We focus on both the decision to move as well as home location selection. We reconfirm the importance of several socio-demographic and macro-economic variables in these decisions as well as identify several other important variables that are relevant to these decision processes.

Halogenated methanes are among the most frequently encountered contaminants at hazardous waste sites. One such site in California is contaminated with chloroform (CF), carbon tetrachloride (CT), and trichlorofluoromethane (CFC-11). CF, CT and CFC-11 are the main focus of this research; they are present at the California site at concentrations in the mg per liter range and a plume of contaminated groundwater emanating from a source zone is approaching a property boundary, necessitating remediation. Anaerobic bioremediation is one of the technologies under consideration for addressing the source zone and the less concentrated downgradient plume. A microcosm study was performed to evaluate natural attenuation, biostimulation and bioaugmentation. Treatment approaches using abiotic processes such as zero valent iron (ZVI), followed by bioremediation, were evaluated in additional experiments. The first objective of this laboratory study was to determine the effectiveness of biostimulation at removing halogenated methanes in the downgradient and upgradient locations. Three types of electron donors were tested; two relatively fast acting (corn syrup and lactate) and one longer lasting (Slow Release Substrate (SRSTM¬), from Terra Systems). The effect of cyanocobalamin (B12) was also evaluated with corn syrup, since the benefits of adding B12 are better documented with corn syrup versus lactate. Addition of B12 was also be evaluated with SRS™, to determine if the same advantages observed with corn syrup can be achieved with a longer-lasting electron donor. For each location, the concentration of major competing electron acceptors (e.g., nitrate and sulfate) was monitored. The second objective was to determine the effectiveness of bioaugmentation for improving the biodegradation rate for halogenated methanes in the downgradient and upgradient locations. KB-1© Plus (containing the required mixture of Dehalobacter spp.) was evaluated for the downgradient and upgradient locations, while DHM-1 was tested with only the higher concentration upgradient location. KB-1© Plus is advantageous from the perspective that it does not require B12 and the downgradient location has low concentrations of potentially inhibitory compounds (e.g., CT). On the other hand, the upgradient location was more likely to have inhibitory compounds and a prior study indicated DHM-1 can be effective in that type of environment. The third objective was to determine the effectiveness of pH adjustment for accomplishing biostimulation and bioaugmentation at the downgradient location. Since groundwater at the downgradient location has a pH greater than 6, bioremediation may be feasible without pH adjustment, although the buffering capacity in this area is not well established. All treatments for the upgradient location were pH-adjusted, since the current pH is already below 6 and dechlorination of higher concentrations of CF will drive the pH even lower. Sodium bicarbonate was used for pH adjustment. The fourth objective was to determine the effectiveness of abiotic and combined abiotic/biotic processes for treating the upgradient location. These processes included ZVI followed by bioaugmentation with KB-1© Plus, sodium dithionite, calcium polysulfide, and a combination of titanium(III) citrate + B12 + corn syrup. The final objective of this study was to perform a mass balance for CF during biodegradation by the KB-1© Plus culture, using 14C-CF. Although previous studies have suggested that the end products are non-hazardous, a complete mass balance to confirm this has not yet been performed. For objectives 1 through 4, five sets of microcosms (i.e., Sets I through V) were prepared with soil and groundwater from the industrial site. For objective 5, only the KB-1© Plus culture was used. Based on results from the microcosms, all of the donor-amended treatments removed CT, in the low and high concentration microcosms. Although the rates differed, removal of CT occurred consistently and is not a major factor in selection of a bioremediation strategy. For the downgradient portion of the plume, the most effective bioremediation strategy for CF and dichloromethane (DCM) is bioaugmentation with KB-1© Plus amended with lactate. pH control does not appear to be necessary; the no pH control (Set II) and microcosms with pH control (Set III) performed similarly. Somewhat unexpected was the robust performance of the pH adjusted microcosms that received lactate as an electron donor. These results suggest that the site contains indigenous Dehalobacter spp. that are capable of organohalide respiration of CF to DCM and fermentation of DCM to nonchlorinated products. Although bioaugmentation with KB-1© Plus amended with lactate was effective for CF and DCM in the downgradient portion of the plume, CFC-11 persisted until most of the CF was consumed, at which point a relatively fast reduction to CHCl2F occurred. For the upgradient portion of the plume, the most effective bioremediation strategy for CF and DCM is bioaugmentation with DHM-1 amended with SRS and B12. This treatment achieved complete removal of CF and significant removal of CFC-11 and DCM. Removal of the DCM suggests that the site contains an indigenous population of anaerobic microbes capable of fermenting DCM as a sole substrate. Bioaugmentation with the KB-1© Plus amended with lactate also showed promise for the upgradient zone, although additional incubation is needed to confirm consumption of DCM formed from CF. Also, KB-1© Plus was less effective in removing CFC-11; follow-up bioaugmentation with DHM-1 should be feasible to address the CFC-11. The high level of sulfate in the downgradient and upgradient groundwater created a high demand for electron donor. Significant improvement in the rate of CFC-11, CF, and DCM biodegradation ensued following an increase in the frequency and amount of electron donor additions after 300 days of incubation, commensurate with the onset of sulfate reduction. This lag could have been shortened significantly by following a much more aggressive schedule of electron donor additions earlier in the incubation period. Lactate and corn syrup were more effective in establishing sulfate reducing conditions than SRS. It is likely that the initially slow rate of electron donor additions resulted in wasteful additions of bioaugmentation culture and B12; these additions should have been made only after sulfate reduction was well established. The sulfide generated from sulfate reduction likely created the low redox conditions that are conducive to halomethane degradation. The most effective abiotic treatment involved the use of ZVI; after approximately three months of incubation, the CT, CF, and CFC-11 were removed. However, DCM and CHCl2F persisted; an attempt to biodegrade DCM by augmenting with KB-1© Plus was ineffective, for reasons that are not yet known. Also, unknown volatile compounds accumulated in the ZVI-amended microcosms. While ZVI was faster than the biotic treatments in this study, this advantage would likely diminish if the biotic-only treatments had received more aggressive additions of electron donor from the outset;. Using 14C-CF, it was shown that the principal product from anaerobic biodegradation of CF by KB-1© Plus is CO2. This is the first report to demonstrate a complete mass balance on the products from CF biodegradation by KB-1© Plus, and to show that these products are nonhazardous. CO2 accumulated in treatments with and without 2-bromoethanesulfonate added (to inhibit methanogenesis), and significant amounts accumulated even when CF was consumed but some DCM remained. This suggests that the pathway for DCM metabolism in the KB-1© Plus culture is different from that reported for Dehalobacterium formi coaceticum, which directly incorporates the carbon in DCM into formate and acetate. The disposition of reducing equivalents gained during fermentation of DCM is not yet known, although a preliminary experiment confirmed that hydrogen accumulates transiently as DCM is consumed. It seems likely that the reducing equivalents formed from DCM are consumed for methane production and/or organic acid formation. These products are not 14C-labeled most likely because the 14CO2 that is generated enters a large pool of bicarbonate in the mineral medium, such that any bicarbonate used for methane or organic acid formation has a low percentage of labeled compound (i.e., the 14CO2 is diluted out).

Fault location detection plays a crucial role in power transmission network, especially on security, stabilization and economic aspects. Accurate fault location detection in transmission network helps to speed up the restoration time, therefore, reduce the outage time and improve the system reliability [1]. With the development of Wide Area Measurement System (WAMS) and Phasor Measurement Unit (PMU), various fault location algorithms have been proposed. The purpose of this work is to determine, modify and test the most appropriate fault location method which can be implemented with a PMU only linear state estimator. The thesis reviews several proposed fault location methods, such as, one-terminal [2], multi-terminal [3]-[11] and travelling wavelets methods [12]-[13]. A Two-stage fault location algorithm using PMU voltage measurements proposed by Q. Jiang [14] is identified as the best option for adaption to operate with a linear state estimator. The algorithm is discussed in details and several case studies are made to evaluate its effectiveness. The algorithm is shown to be easy to implement and adapt for operation with a linear state estimator. It only requires a limited number of PMU measurements, which makes it more practical than other existing methods. The algorithm is adapted and successfully tested on a real linear state estimator monitored high voltage transmission network.