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Aims: This research was aimed to cross-culturally validate seven reliable measures that frequently used in Acceptance and Commitment Therapy (ACT) for the Chinese populations. The Acceptance and Action Questionnaire-II (AAQ-II), Cognitive Fusion Questionnaire (CFQ), Engaged Living Scale (ELS), Bref Experiential Avoidance Questionnaire (BEAQ), Self-Compassion Scale (SCS), and Five Facet Mindfulness Questionnaire (FFMQ), and Valued Living Questionnaire (VLQ) were selected to be validated. Design and Methods: The ACT measures for Chinese people were adapted based upon the results of 800 non-clinical participants and 154 clinical participants in China. Various psychometric properties had been investigated in four studies, including content validity, factorial validity, reliability, measurement invariance, convergent validity, incremental validity and potential criterion validity. Results: After the validation, the Chinese version of AAQ-II, CFQ, and VLQ (C-AAQ-II, C-CFQ, and C-VLQ) had retained all the items and a one-factor model. The other validated measures, including the Chinese version of ELS, BEAQ, SCS, and FFMQ (C-ELS, C-BEAQ, C-SCS, and C-FFMQ) had all eliminated some items or changed in the factorial model. The adapted Chinese version of all the above measures showed good factorial validity and reliability in both non-clinical and clinical samples. The C-AAQ-II, C-CFQ, C-ELS, C-SCS, and C FFMQ also demonstrated good convergent validity and might be able to predict the overall psychological distress and quality of life, whereas C-BEAQ showed relatively poor convergent validity and insufficient ability to predict psychological symptoms. The C-VLQ revealed acceptable convergent validity in both samples, whereas it weakly correlated with other ACT constructs, psychological symptoms and quality of life when applied to the non-clinical participants. Moreover, except C-BEAQ, it had been shown that all the other adapted measures might be able to distinguish the clinical participants from the non-clinical participants. Conclusion: The psychometric properties of validated ACT measures might suggest that C-AAQ-II, C-CFQ, C-ELS, C-SCS, C-FFMQ, and C-VLQ have overall good validity and reliability. However, the C-BEAQ retained a less valid construct in the Chinese context. The discussions were also made on cross-cultural validation issues, cross-cultural perception of ACT concepts, implementation of Chinese ACT measures in research and clinical practice, strengths, limitations and proposing future research directions.

With sizes ranging from 1 to 10 nm, macroions demonstrate attractive and unique solution behaviors which cannot be described either by Derjaguin-Landau-Verwey-Overbeek (DLVO) theory or Debye-Hückel theory. With charges carried by macroions, most of them show great solubility in polar solvent, and electrostatic interaction possesses a significant role in their solution behaviors. As single molecules, the association of counterions to macroions, based on electrostatic interaction, could show spatial predilection due to variable constructive units within macroions and the large size disparity between macroions and counterions. With moderate charges, many of macroions are capable to spontaneously self-assemble into single-layer hollow spherical blackberry-like structures via counterion-mediated attraction, which can be accurately controlled by pH, solvent polarity, and electrolyte concentration. Based on the complex structures of macroions, various interactions, such as hydrophobic interaction, hydrogen bonding, and sigma -π interactions, can be involved to compete or cooperate with electrostatic interaction to regulate their solution behaviors and achieve multiple self-assembled structures. Furthermore, with the larger supramolecular structures formed by macroions, phase transitions, such as sol-gel transition, take place. Therefore, exploring the solution behaviors of macroions at their single-molecular, self-assembled states, and consequent phase transition would be an efficient method to understand weak non-covalent interactions in the system, which are difficult to evaluate via traditional tools.In this work, the structural well-defined metal-organic cages (MOCs) and uranyl peroxide molecular clusters serve as great models for understanding the solution behaviors of macroions either at single-molecular state or during their self-assembly processes. A series of MOCs with aggregation-induced emission (AIE) luminophores are designed and prepared. The change in fluorescence emission offers direct visualization of microenvironment changing around AIE luminophores based on effect from macroions, counterions and solvent molecules, which provides further understanding on their solution behaviors. Multiple self-assembled structures, e.g., nanosheets and blackberry-type structures, are observed, regulated by electrostatic interactions, sigma-π interactions, anion-π interactions and so on. Their optical properties and resulting assemblies in the systems mentioned above are characterized by static light scattering (SLS), dynamic light scattering (DLS), transmission electron microscopy (TEM), high-resolution scanning electron microscopy (HRSEM), small-amplitude oscillatory shear (SAOS), isothermal titration calorimetry (ITC), conductivity, fluorescence spectroscopy and UV-vis absorption, etc.

Solar and wind power have become the dominant renewable energy technologies around the world. Hybrid PV and wind plants are gaining much interest due to their ability to take advantage of different weather systems at different times of the day. A comprehensive analysis has been performed to investigate the complementary features of solar and wind resources for a hybrid PV and wind power plant. Four different forecasting methods were applied for both solar PV and wind forecasting, including persistence, Elman neural network (ENN), wavelet neural network and autoregressive integrated moving average (ARIMA). To reduce the uncertainty associated with forecasting, battery energy storage systems (BESS) were optimised to address the problems arising from the variability in renewable energy generation. In this study, the BESS size was first determined using an analytical method with financial criteria. An economic optimisation model was developed to minimise the total operation cost of the hybrid system and attain an optimum size for the battery. To further understand the factors that impact battery sizes underneath the optimisation model, forecasting errors were decomposed in both the time and frequency domains revealing the distinct impacts of time and frequency domain components on battery sizing. Another key finding is the discovery that the required battery size favours biased forecasting when the battery model considers round-trip efficiency. This study also optimised the scheduling of the BESS using forecasting information. A mixed receding horizon control (RHC) strategy was presented to minimise the total operation cost of the entire system, including the profits from selling electricity, the costs from purchasing ancillary services for undersupply and oversupply, and the operation and maintenance costs of each component. The strategy made full use of both long-term and short-term forecasting information to improve optimisation performance. The simulation demonstrated the efficiency of the proposed mixed receding horizon strategy, which reduced the total operation cost by almost 29% in one year, in contrast to other previously presented strategies.

As high precision data acquisition systems continue to improve their performance and power efficiency to migrate into portable devices, increasing demands are placed on the performance and power efficiency of the analog-to-digital conversion modulator. On the other hand, analog-to-digital modulator performance is largely limited by several major noise sources including thermal noise, flicker noise, quantization noise leakage and internal analog and digital coupling noise. Large power consumption and die area are normally required to suppress the above noise energies, which are the major challenges to achieve power efficiency and cost targets for modern day high precision converter design. The main goal of this work is to study various approaches and then propose and validate the most suitable topology to achieve the desired performance and power efficiency specifications, up to 100 kHz bandwidth with 16-21 bits of resolution. This work will first study various analog-to-digital conversion architectures ranging from Nyquist converters such as flash, pipeline, to the delta sigma architecture. Advantages and limitations of each approach will be compared to develop the criteria for the optimal modulator architecture. Second, this work will study analog sub-circuit blocks such as opamp, comparator and reference voltage generator, to compare the advantages and limitations of various design approaches to develop the criteria for the optimal analog sub circuit design. Third, this work will study noise contributions from various sources such as thermal noise, flicker noise and coupling noise, to explore alternative power and die area efficient approaches to suppress the noise. Finally, a new topology will be proposed to meet all above criteria and adopt the new noise suppression concepts, and will be demonstrated to be the optimal approach. The main difference between this work from previous ones is that current work places emphasis on the integration of the modulator architecture design and analog sub-circuit block research efforts. A high performance stereo analog-to-digital modulator is designed based on the new approach and manufactured in silicon. The chip is measured in the lab and the measurement results reported in the dissertation.

Molecular level information for carbon monoxide and methanol electrooxidation is provided by in situ surface-enhanced Raman spectroscopy (SERS) in this work for better understanding the mechanism of CO and methanol electrooxidation on transition metals. Electrooxidation of CO and methanol on transition metals are studied by cyclic voltammetry and in situ SERS. Thickness effect of overlayer metals on CO adsorption and oxidation activity is studied and explained by the strain effect and ligand effect. The cumulative effect for CO oxidation on Pd is the positive shift of CO oxidation peak position. Both the strain effect and ligand effect cause the negative shift of CO oxidation on Pt. Methanol electrooxidation on Ru is demonstrated by the C-O stretching band from COads on Ru oxide in SER spectra, which suggests that at higher potentials methanol oxidation on Ru sites needs to be taken into account in the catalytic mechanism of Pt-Ru catalysts in the direct methanol fuel cell.