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Under the current results-driven development agenda, sound evaluation, and a corresponding evaluation toolkit, need to be in place to examine whether and to what extent development interventions have achieved their targeted objectives and results, and to generate lessons for further development learning and improvement. My review of the literature shows that innovative and appropriate evaluation approaches are needed to address key challenges in evaluation such as the tension between learning and accountability objectives, the need to unpack the mechanisms linking outputs and outcomes or goal, and to add an actor perspective. Irrespective of project type, the Logical Framework Approach (LFA) is often a standard requirement of major official donor agencies on projects they fund, so as to fulfil bureaucratic imperatives. However, it is often considered inadequate in addressing key challenges in development evaluation. Given the dominant status of the LFA with such strong support from donors, it is helpful to seek a ‘middle way': a combination of the LFA with other approaches in order to address some of its inadequacies, while satisfying donor agencies' requirements. A synthesis of the LFA and Outcome Mapping (OM) is one such option. This thesis explores the practical value and usefulness of a synthesis model empirically. Applying the model in two case study aid projects, I found that it serves well as a theory-based evaluation tool with a double-stranded (actor strand and results chain) theory of change. The model helps reconcile learning and accountability and add explanatory power and an explicit actor perspective. It also helps establish causation and enable attribution claims at various results levels with its different elements. The model has some limitations but my results suggest it can be usefully adopted. The choice of its application depends on project evaluation context and purpose in specific cases.

Future communication networks promise to provide ubiquitous high-speed services for numerous users, as such, it is envisioned that one of the key aspects of the next generation of communication network is the deployment of different types of access points, e.g. small cells (SCs), on a massive scale. Meanwhile, energy efficiency (EE) has become an important feature for designing the next generation of communication networks and offering good user experience to all users while incurring low operational cost to the operators. In this context, this thesis focuses on the design of a novel green scheduling framework for improving both the EE and user fairness in the underlay HetNet scenario. Focusing on the user/subcarrier allocation, we design an EE-based allocation boundary which dynamically categorises users into inner area and cell-edge users. Our dynamic resource allocation boundary is updated at every scheduling interval such that it can capture the time-varying characteristics of the mobile networks, contrary to the fixed boundaries used in long-term planning schemes (e.g. fractional frequency reuse). This dynamic allocation boundary is used to design a green scheduling scheme and can improve the EE of an underlay HetNet system by up to 70% as compared to existing schemes. Focusing on the power allocation algorithm, a low-complexity energy-efficient power allocation algorithm is designed to coordinate the macro and underlay SCs and fully exploit the transmit power reduction capability of SCs. By applying a symmetric user grouping method, it is shown that the original non-convex EE optimisation problem can be transformed into a pseudo-convex problem, where the optimal power allocation can be obtained for a given user/subcarrier allocation. This energy-efficient power allocation algorithm is further incorporated with the dynamic allocation boundary which improves the EE (up to 70%) and user fairness (up to 50%) compared to existing algorithms in the underlay HetNet.

Humic acid (HA) can effectively bind several hazardous metals. The interaction between HA and metal ions plays an important role in metal mobility and bioavailability in the environment. Abiotic humification processes can provide a potential and promising way to synthesize humic acids with better metal binding ability than their naturally occurring counterparts. The aim of the PhD project is to investigate the synthesis and application of synthetic humic-like acid (SHLA) for water/wastewater treatment and soil remediation. This thesis showed the log K and complexation efficiency of SHLA were higher at higher pH, lower ionic strength, higher temperature and higher SHLA concentration, and the effects of the above environmental factors on the complexation reaction are similar to natural HAs. Eleven SHLAs were prepared via a range of abiotic humification conditions. The results showed that SHLAs with a higher content of carboxylic groups, more aromatic structures and a higher degree of humification, would have a better Cu complexation ability. The optimal abiotic humification conditions to synthesize SHLA with better copper complexation ability were also determined. When applied as a soil washing agent, SHLA was more effective than some common washing agents, like Na2EDTA, citric acid, commercial HA and tartaric acid, and reduced the bioavailability and environmental/human health risk of metals. When applied as an adsorbent, the adsorption process between SHLA and Cu2+ was favourable, spontaneous and endothermic, and was described by the pseudo-second-order kinetic model, Langmuir and Freundlich models. The Cu2+ adsorption capacity of SHLA was much higher than many of the humic acid-based materials reported in the literature and the SHLA can be regenerated by HCl. Besides, SHLA was able to remove co-contaminant metals from solution. When applied as a soil amendment, SHLA lowered the bioavailability of Cu, Zn and Ni, but increased the bioavailability of As. Besides, the addition of SHLA could increase TOC and WSC of soil but decrease the soil pH. This thesis has shown that it is possible to synthesize SHLAs that show great promise for use in remediation of contaminated water sources and soils.

This thesis studies three aspects of gravity in quantum field theory. First quantum gravity effects are investigated using effective field theory techniques. In particular, we consider quantum gravity effects in grand unified theory and study their effects on the unification of the masses in such models. We find that the fermion masses unification conditions receive a sizeable correction from the quantum gravitational effects and one thus cannot predict the high energy unification only by the extrapolation from low energy physics without the understanding of gravitational effect in high energy. Secondly we study quantum field theory in curved spacetime in order to understand further about some of the properties of gravity. Keeping gravity as background field we discuss modified gravity theories in different set of parameters called frames; they are the Jordan frame and the Einstein frame respectively. We show how to map gravitational theories at the quantum field theoretical level. The key observation is that there is a non-trivial Jacobian. It can be interpreted as boundary term. Finally we investigate a new canonical quantisation paradigm. In that framework, quantum gravity is power counting renormalisable. Furthermore, the theory is unitary and the problem of time is solved. We use this framework to calculate the solution for the quantum wave function and the semiclassical Hamilton-Jacob function. We study the Hawking-Bekenstein entropy in the spherical symmetric mini-superspace for Schwarzschild black hole, and find that it can be produced naturally from first principles. Importantly it is accompanied naturally by non-thermal quantum correction terms which is generally believed to restore the information loss.

While the structure and mechanical properties of natural cellular solids such as wood and trabecular bone have been extensively studied in the past, the structural design and underlying deformation mechanisms of natural cellular solids with very high mineral contents (> 90 wt%), which we term as natural ceramic cellular solids, are largely unexplored. Many of these natural ceramic cellular solids, despite their inherent brittle constituent biominerals (e.g., calcite or aragonite), exhibit remarkable mechanical properties, such as high stiffness and damage tolerance. In this thesis, by carefully selecting three biomineralized skeletal models with distinctly different cellular morphologies, including the honeycomb-like structure in cuttlefish bone (or cuttlebone), the stochastic open-cell structure in sea urchin spines, and the periodic open-cell structure in starfish ossicles, I systematically investigate the mechanical design strategies of these natural ceramic cellular solids. The three model systems are cuttlefish Sepia officinalis, sea urchin Heterocentrotus mammillatus, and starfish Protoreaster nodosus, respectively. By investigating the relationship between their mechanical properties and structural characteristics, this thesis reveals some novel structural design strategies for developing lightweight, tough, strong, and stiff ceramic cellular solids. The internal skeleton of S. officinalis, also known as cuttlebone, has a porosity of 93 vol% (constituent material: 90 wt% aragonite), which is a multichambered structure consisting of horizontal septa and thin vertical walls with corrugated cross-sectional profiles. Through systematic ex-situ and synchrotron-based in-situ mechanical measurements and collaborative computational modeling, we reveal that the vertical walls in the cuttlebone exhibit an optimal waviness gradient, which leads to compression-dominant deformation and asymmetric wall fracture, accomplishing both high stiffness (8.4 MN∙m/kg) and high energy absorption (4.4 kJ/kg). Moreover, the distribution of walls reduces stress concentrations within the horizontal septa, facilitating a larger chamber crushing stress and more significant densification. For the stochastic open-cell foam-like structure, also known as stereom (porosity: 60-80 vol%, constituent material: 99 wt% calcite) in H. mammillatus, we first developed a computer vision-based algorithm that allows for quantitative analysis of the cellular network of these structures at both local individual branch and node level as well as the global network level. This open-source algorithm could be used for analyzing both biological and engineering open-cell foams. I further show that the smooth, highly curved branch morphology with near-constant surface curvature in stereom results in low-stress concentration, which further leads to dispersed crack formation upon loading. Combined synchrotron in-situ analysis, electron microscopic analysis, and computational modeling further reveal that the fractured branches are efficiently jammed by the small throat openings within the cellular structure. This further leads to the formation of damage bands with densely packed fracture pieces. The continuous widening of the damage bands through progressive microfracture of branches at the boundaries contributes to the observed high plateau stress during compression, thereby contributing to its high energy absorption (17.7 kJ/kg), which is comparable and even greater than many synthetic metal- and polymer-based foams. Lastly, this thesis leads to the discovery of a unique dual-scale single-crystalline porous lattice structure (porosity: 50 vol%, constituent material: 99 wt% calcite) in the ossicles of P. nodosus. At the atomic level, the ossicle is composed of single-crystal biogenic calcite. At the lattice level, the ossicle's microstructure organizes as a diamond-triply periodic minimal surface (TPMS) structure. Moreover, the crystallographic axes at atomic and lattice levels are aligned, i.e., the c-axis of calcite is aligned with the [111] direction of the diamond-TPMS lattice. This single crystallinity co-alignment at two levels mitigates the compliance of calcite in the c-axis direction by utilizing the stiff direction of the diamond-TPMS lattice. Furthermore, 3D in-situ mechanical characterizations reveal that the presence of crystal defects such as 60° and screw dislocations at the lattice level suppresses slip-like fracture along the {111} planes of the calcitic diamond-TPMS lattice upon loading, achieving an enhanced energy absorption capability. Even though the skeleton of echinoderm is made up of single-crystal calcite, the structure fractures in a conchoidal manner rather than along the clipping plane, which can continuously fracture the fragments into small pieces and enhance energy dissipation.

The future of new physics searches at the LHC will be to look for hadronic signals with jets. In order to distinguish a hadronic signal from its background, it is important to develop advanced collider physics techniques that make accurate theoretical predictions. This work centers on phenomenological and formal studies of Quantum Chromodynamics (QCD), including resummation of hadronic observables using Soft Collinear Effective Theory (SCET), calculating anomalous dimensions of multi-Wilson line operators in AdS, and improving jet physics analysis using multiple event interpretations., Physics

Satellite nadir altimetry uses a space-based sensor to repeatedly measure the height, allowing geodesists and other Earth scientists to monitor temporal changes in surface height on a global or regional basis. Satellite altimetry was originally designed for observing and monitoring global ocean surface topography, but innovative methodologies have been developed and demonstrated for sensing non-ocean surfaces. In this study, two non-ocean altimetry applications have been explored and examined: lake ice thickness retrieval in the Laurentian Great Lakes, and land subsidence rate derivation at San Joaquin Valley. For lake ice thickness study, because there is not yet an operational satellite-based observing system in the Great Lakes, we explore the feasibility of lake ice thickness retrieval using satellite radar and laser altimetry. Cryosat-2 Low Resolution Mode and one-year long ICESat-2 Inland Water Surface Height data product are used to estimate lake ice thickness during the winter 2011 through winter 2019 using the ice freeboard method, which has been extensively used for polar sea ice thickness retrieval but has not yet been applied for lake ice thickness change studies. The Cryosat-2 radar altimeter estimated ice thickness is compared with in-situ data, the difference is 0.2 m., indicating excellent agreements. The Cryosat-2 solution is further compared with ice cover and air temperature data, the correlation coefficients are larger than 70% in Lake Superior, Erie and Ontario, implying the validity of the altimeter-derived interannual variability of lake ice changes. We also discover that Cryosat-2 ice thickness and ice cover data have strong linear relationship. The one-year long ICESat-2 dataset is used, for the first time, to quantify the ice thickness in Great Lakes region in the winter 2019. Comparison between Cryosat-2 and ICESat-2 derived ice thickness, the Cryosat-2 observable shows higher estimates due to problem of penetration in snow layer for both missions. We compare both altimetry derived ice thickness with United States Coast Guard (USCG) estimated values, and found that both altimetry derived ice thickness values are higher than the USCG estimates. The reason might be USCG estimated ice thickness do not account for ridging, causing theses estimates to be lower than the actual values. One winter in-situ ice thickness data is not enough to confirm, more in-situ data are needed for further validations. For land subsidence rate derivation study, we develop a new method to generate 0.3° x 0.3° two-dimensional deformation map using Cryosat-2 Low Resolution Mode data and spatial interpolation method. The results show that the Cryosat-2 derived deformation map agrees well with the GPS, Jason-2 altimeter, NASA JPL InSAR estimated velocities, and in-situ data from cumulative groundwater well. The largest subsidence bowl is identified near the city of Corcoran, California, USA, with the maximum subsidence rate -30 ~ -35 cm/yr due to excessive anthropogenic groundwater pumping. In addition, we implement Kuo et al. (2015) method to process conventional pulse-limited radar altimetry missions, including Envisat, Jason-2 and Jason-3, over land for subsidence. The results show good agreement with the GPS data, and seasonal and flood signals are sensed in altimetry derived time series. It is anticipated that the altimetry observations from this study can be used to validate and complement other spaceborne and in-situ sensors, such as GNSS, InSAR and leveling data.

This dissertation research aims to develop and evaluate methods for noninvasive cardiac imaging of activation sequence and activation recovery interval (ARI), and localization of ventricular arrhythmias. It includes (1) developing a novel imaging method (SSF, Spatial gradient Sparse in Frequency domain) for the reconstruction of activation sequences in ventricular arrhythmias, (2) developing ARI imaging technique to reconstruct the ARI maps in premature ventricular contraction (PVC) patients from body surface potential maps, (3) proposing a CNN-based (convolutional-neural-network-based) method to localize origins of PVCs from 12-lead electrocardiography (ECG). SSF is implemented in the frequency domain, and the activation time was encoded in the phase information of the solution. The performance of SSF was evaluated in computer simulation and a swine model with myocardial infarction. SSF is the first noninvasive imaging method reported that could reconstruct the reentry circuit in 3-dimensional space. SSF achieved better performance with less computational time. ARI imaging reconstructed 3D ARI maps in ventricles, which were compared with the endocardial ARI maps from CARTO recordings. From the analysis of 100 PVC beats in ten patients, the results suggest that it could serve as an alternative of evaluating global dispersion of ventricular repolarization and could guide ablation procedure in PVC patients. The CNN-based method consists of two CNNs (Segment CNN and Epi-Endo CNN). The inputs are from 12-lead ECG. The origins of PVC are localized by calculating the weighted center of gravity of classification returned by the CNNs. It was evaluated in computer simulation and in 90 PVC beats from nine patients. The results demonstrate the capability and merits of the proposed method for localization of PVC. This work suggests a new approach for cardiac source localization of origins of arrhythmias using only the 12-lead ECG by means of CNN.

The southern house mosquito, Culex quinquefasciatus, is an important disease vector of West Nile virus (WNV), Saint Louis encephalitis virus (SLEV), and filariasis. Insecticides are the most important component in the vector-control effort. Pyrethroids are currently the most widely used insecticides for indoor sprays of mosquitoes worldwide. However, mosquitoes have developed resistance to insecticides. An improved understanding of the mechanisms governing insecticide resistance is necessary and would be helpful to develop novel strategies for preventing resistance development, and controlling resistant mosquitoes. A mosquito strain of Cx. quinquefasciatus, HAmCqG0, was collected from Huntsville, Alabama, and established in the laboratory in 2002. The level of resistance to permethrin in the HAmCqG0 strain is 10-fold, compared with an insecticide susceptible mosquito strain S-Lab, which has served as reference strain. The strain, HAmCqG8, was the 8th generation of permethrin-selected offspring of HAmCqG0, with a resistance level to permethrin at 2700-fold compared with S-Lab strain. There are multiple mechanisms reported to be involved in pyrethroid insecticide resistance, including two major ones, cytochrome P450-mediated detoxification and voltage-gated sodium channel insensitivity. In order to gain insight in understanding the mechanisms conferring pyrethroid resistance in the Culex mosquito, I investigated the distribution of the resistance levels in the field strain HAmCqG0 to permethrin by isolating 104 single-egg-raft colonies. I further characterized both the frequency of the L-to-F kdr mutation allelic expression of sodium channels and the expression levels of multiple up-regulated cytochrome P450 genes in single-egg-raft colonies with different levels of resistance to determine their possible roles in resistance. To better understand the mechanism of cytochrome P450-mediated detoxification involved in insecticide resistance, I demonstrated the expression profiles for the total 204 P450 genes that are reported in the genome of Cx. quinquefasciatus from different strains bearing different pyrethroid resistance phenotypes (susceptible, intermediate and highly resistant). My objectives were to pinpoint the key P450 genes involved in insecticide resistance. With those key P450 genes identified, I then examined their functions in conferring resistance using double-stranded RNA-mediated gene interference (RNAi) techniques, and revealed that silencing the expression of up-regulated genes in mosquitoes resulted in a reduction of resistance. Furthermore, characterization of transgenic lines of Drosophila melanogaster with the mosquito P450 genes showed an induction of the levels of tolerance to permethrin in these transgenic lines. Taken together, my research indicated that multiple up-regulated P450 genes are co-responsible for detoxification of insecticides and insecticide selection, and also that multiple mechanisms co-work on the development of insecticide resistance in mosquitoes.

Nowadays a substantial trend occurs that vast amounts of geospatial data are supplied, managed, and processed over distributed GIS. It is important to provide users with the capability of visualising spatial data quality information in a meaningful way for distributed GIS, since it will significantly enhance user understanding of data quality and aid them in assessing the data fitness for their application requirements. This thesis investigates the issue of visualisation of spatial data quality for distributed GIS. Based on a review of core concepts associated with spatial data quality, metadata standards, and major research areas related to data quality, the limitations of current data quality presentation are highlighted. To overcome some of these limitations, the research topic of this thesis is proposed, namely, adding visualisation functionality to the presentation of spatial data quality to convey uncertainty information to users in an interactive and graphical manner. Based on a review of the theories on visualisation and the frameworks developed for visualisation of spatial data quality in literature, an extended framework is developed incorporating several aspects of visualisation such as contexts, contents, and techniques, where the hierarchical nature of data quality and error models are two main parts of the visualisation contents. A brief framework of visualisation of spatial data quality for distributed GIS is proposed, where data storage with quality information and web services for visualising data quality are two key components. To satisfy a series of requirements for representing spatial data quality, a new object-oriented data model is proposed based on the review of developments of data models. This data model can specifically deal with the hierarchical nature of data quality and error propagation, recognising data quality as a dynamic process. Further, The implementation of the data model using GML and SVG is discussed. The details of a web service for visualising spatial data quality are addressed. After proposing the requirements on building a system for spatial data quality visualisation for distributed GIS, the design of a prototype visualisation system for distributed GIS is addressed in detail. The prototype visualisation system for spatial data quality is developed and implemented with an example data set, where SVG and JavaScript are used to illustrate how various graphic methods such as animation, data quality filters, and colour gradients can be used for distributed GIS. In addition to the visualisation of positional accuracy at the feature level, in this pilot system, the hierarchical structure of data quality information is also presented. Limitations of the research in this thesis are also addressed. However, in general, this research is of great significance for the contributions made to a relatively new research area in terms of theories, procedures, and software developments.