According to the legally binding target for European governments, by 2020, 15-20% of the EU`s energy consumption should be produced from renewable sources. Furthermore, according to the National Grid`s estimate for future energy scenarios in the UK, by 2035/36 (according to the "Gone Green" future scenario) annual electricity demand could potentially reach 375TWh/year with the residential consumption energy forming 33% of the total electricity demand [3]. As claimed by the same scenario, Renewable Generation (RG) will represent 53% of the installed capacity and will provide 50% of the generated energy with wind and PV contributing almost 46% of the supply mix. The combination of integrating intermittent RG, reducing fossil fuel based generation and the electrification of heat and transport (which will inevitably lead to higher electricity demand), means that if the current electricity transmission and distribution system remains unchanged, it will struggle to meet: • Reduce Power quality • Overloading of distribution equipment (e.g transformers and feeders) • Increasing network losses • Higher number of system frequency deviations • Increased voltage unbalance • Fault detection and Location In systems dominated by Renewable Energy Sources (RES) the dominant challenges will be the reduced inertia of the electrical system and the associated increasing need for frequency regulation services. Over recent years small home Battery Energy Storage Systems (BESS) in combination with solar PV systems have become commercially available and more affordable. The storage capacity of new, small scale residential BESS units (e.g Tesla Powerwall) is also increasing. The aim of this project is to investigate how domestic Battery Energy Storage Systems can contribute to Frequency Regulation services and at the same time provide benefit for electricity end-users through achieving local community objectives such as reduction of import at peak tariff periods and increased "self-consumption" of locally generated renewable energy. Furthermore, it will explore if the creation of energy community entities can improve these. In the process of tackling these questions a novel hierarchical control framework has been proposed which is able to exploit community BESS, for both local/community benefit and system benefit. In addition, while simulating the proposed control framework a novel electric vehicle model (EV) was developed in order to aid the investigation of future energy scenarios. Real time data from photovoltaic systems and the electrical system frequency data were analysed and used to understand the requirement for Frequency Regulation Services. This informed the development of a novel higher level control, the Adaptive Community Power Profiler - Energy Management System (ACPP-EMS) which was able to provide local and national benefit through controlling BESS in small communities with low level real time controllers by imposing Power Profiling targets to achieve multiple objectives. Simulation studies demonstrate the benefits provided by this controller.

The flow-induced vibration is one of the most common vibrational phenomena in the ambient environment, on which the previous studies were mainly dealing with methodologies as to how to control and reduce vibrations of objects in the flow field. Facing the growing demand of the power supply of the Internet of Things (IoT) and the Wireless Sensor Network (WSN), the energy harvesting technique utilizing multifaceted dynamic effects incurred within natural water flows is a new and meaningful area worth of further research. In this thesis, two novel strategies of the flow-induced vibration energy harvesting techniques were proposed and investigated. One is focused on the flow pattern control with the creative layouts of the bluff bodies. The other could harvest the energy from the reciprocating water flows with the utilization of the torsional vibration mode of the energy harvester. Both methods were firstly proposed and verified in this thesis. The work could not only develop the power output of the energy harvester, but also be applied in the actual hostile ambient environment. The contributions to the research provided by this thesis were made also on the optimization of the proposed topologies with numerous experimental, analytical and computational approaches. The detailed characteristics were investigated and concluded in the thesis to promote the applications of the technologies. The energy storage system was also studied and tested.

Decentralised energy systems (DES) can be seen as a promising network topology which can potentially address the 21st century energy and power challenges that the existing hierarchical, centrally controlled power grid is required to face. Comprehensive design and representation of such systems are among the many obstacles which restrict the wider spread of DES. This thesis is concerned with the feasibility and profitability of small scale grid-connected DES located in UK. A suitable design and development procedure was proposed in this study for the analytical and detailed representation of the systems considered. The design procedure followed was integrated with the control, management and sizing strategies via the monitor of the system operation and the power flow. The effect of different technical parameters on the system performance and viability was investigated and the outcome was utilised in planning and scheduling decisions. Finally, comparisons between different specific test scenarios, energy systems, overnight charging control algorithms, energy storage sizes, etc. were implemented and conclusions regarding the system financials were drawn. This study can be seen as a design and sizing guide or a process simulation interactive software which provides design recommendations, sizing guidelines and useful system insights to the end users and the management authority/aggregators.

Attributed to the superior electrical and thermal properties, wide band gap semiconductors have been considered as the next generation electronic materials, among which 4H-SiC is the most mature technology. Even though, currently wide band gap devices are still not widely adopted, mainly due to the much higher cost compared with conventional Si devices. Large area 3CSiC wafer grown directly on Si substrate is considered as one of the approach to make wide band gap materials more cost attractive. As such, this thesis is focused on the developments of fabricating semiconductor devices on 3C-SiC/Si materials. A degenerate wide band gap semiconductor is a rare system. In general, dopant energy levels lie deeper in the band-gap and carriers freeze-out even at room temperature. Nevertheless, we observed that heavily doped n-type degenerate 3C-SiC films are achieved by nitrogen implantation level of 6×1020 cm-3 at 20 K. Free donors are found to saturate in 3C-SiC at 7 × 1019 cm-3 and fully thermally ionized at 150 K. Ohmic contacts (Ti/Ni bilayer) were manufactured on these implanted 3C-SiC surface and the electrical characterisation revealed the unique accumulation-type metal-semiconductor interface. As-deposited Ti/Ni Ohmic contact was obtained with low contact resistivity around 2×10-5 Ω.cm2 and even lower contact resistivity approaching 1×10-6 Ω.cm2 was achieved by performing a post metallisation annealing at 1000°C for 1 min after the contact deposition. Both lateral MOS capacitors and lateral MOSFETs were fabricated on 3C-SiC(001)/Si wafers to study the 3C-SiC/SiO2 interface. Oxidation temperature above 1200°C turned out to have negligible influence on the final MOSFET peak channel mobility. O2 dry oxidised MOSFETs readily have a relatively high mobility around 70 cm2/V.s while a N2O post oxidation annealing further increases it to 90 cm2/V.s. LDMOSFETs were fabricated on 3C-SiC(001)/Si wafers. Despite of the low current density of 1.37 A/cm2, it is still more than 10 times higher than the 4H-SiC reference device. Finite element simulation demonstrated that the 3C-SiC/Si lateral device current density can be greatly increased (above 3 times) using novel RESURF structures.

The main challenge of adsorption systems today is to improve the performance of the thermal generator in order to make adsorption systems economically viable. The key novelty of this doctoral thesis is its evaluation of the potential use of a new refrigerant, R723, in an adsorption system using activated carbon as adsorbent. Granular activated carbon is a well-known and effective adsorbent in adsorption systems. The R723 refrigerant was introduced into the market in early 2004; this new refrigerant is an azeotropic mixture of 40% ammonia and 60% dimethyl ether by mass. The new refrigerant is compatible with copper alloy (Cu-Ni 90/10), in comparison with ammonia, which is only compatible with stainless steel. The high thermal conductivity of Cu-Ni 90/10 causes an improvement in heat exchange in the thermal generator. This work investigates the effect of granular activated carbon packed bed density on gas permeability. A correlation was found between granular activated carbon packing density and refrigerant pressure drop over the thermal generator. The porosity of granular activated carbon in terms of adsorbing the R723 was determined. The porosity was evaluated using the gas mixture adsorption theory and using the porosity experimental data for granular activated carbon / ammonia and granular activated carbon / dimethyl ether pairs. The performance of the adsorption system for different applications was determined with the activated carbon / R723 pair. The effects of concentration of R723 and granular activated carbon packing density on the thermal parameters of activated carbon packing, including the thermal conductivity and heat transfer coefficients of the contact wall/packed carbon, were studied simultaneously. A correlation was established showing the connection between the thermal parameters of the packed bed, and the concentration of R723 and the density of the granular activated carbon packed bed. Finally, this thesis demonstrates modelling procedures for a tubular generator with the granular activated carbon (208-C) / R723 pair, with regard to different applications such as air conditioning, ice making and a heat pump. The model under consideration included the ideal desorption effect without heat and mass recovery, while imposing the ideal temperature jump into the boundary of the tubular generator. During the modelling, information such as driving temperature (Tg), coefficient of performance (COP), and specific cooling and heating powers (SCP & SHP), was collected. The collected information was used to established a correlation in order to estimate the optimum driving temperature, COP, SHP and SCP, based on different governing parameters, such as granular activated carbon packing density, outside diameter (OD) and the length of the thermal generator. This information is useful in choosing the correct typical standard tube size of the thermal generator with the granular activated carbon (208-C) / R723 pair for specific applications, based on optimum governing parameters, such as the range of heat source availability and the power requirement. The other key point which was examined was the effect of tubular generator body material on COP and SCP (SHP) for different applications. The model used stainless steel and Cu-Ni 90/10 with standard wall thickness.

The aim of this thesis is to provide techniques for the analysis of a variety of types of spatial data, each corresponding to one of three biological questions on the function of the protein TACC3 during mitosis. A starting point in each investigation is the interpretation of the biological question and understanding of the form of the available data, from which a mathematical representation of data and corresponding statistical problem are developed. The thesis begins with description of a methodology for application to two collections of (marked) point patterns to determine the significance of differences in their structure, achieved through comparison of summary statistics and quantification of the significance of such differences by permutation tests. A methodology is then proposed for application to a pair spatio-temporal processes to estimate their individual temporal evolutions, including ideas from optimal transportation theory, and a test of dependence between such estimators. The thesis concludes with a proposed model for line data, designed to approximate the mitotic spindle structure using trajectories on the surface of spheroids, and a comparison score to compare model t between models and/or observations. The results of methodologies when applied to simulated data are presented as part of investigations into their validity and power. Application to biological data indicates that TACC3 influences microtubule structure during mitosis at a range of scales, supporting and extending previous investigations. Each of the methodologies is designed to require minimal assumptions and numbers of parameters, resulting in techniques which may be applied more widely to similar biological data from additional experiments or data arising from other fields.

The research presented in this thesis focuses on the use of B-g CsSnI3 perovskite as the light harvesting semiconductor in discrete layer photovoltaic (PV) devices. Chapters 1 and 2 give a brief introduction with relevant theory, and experimental techniques respectively. Chapter 3 describes the use of B-g CsSnI3 in PV devices based on a CuIj CsSnI3j fullerene architecture, showing how device Voc is strongly dependent on the energetics at the perovskite fullerene interface, and that using excess SnI2 in CsSnI3 preparation greatly improves device stability. Chapter 4 describes the effect that different tin halides have on stabilising films of B-g CsSnI3 and on the performance of PV devices. SnCl2 was found to be the most beneficial source of excess Sn, with the champion device achieving a power conversion efficiency of over 3.5% combined with remarkable stability. Spontaneous n-type doping of the fullerene layer by SnCl2 is shown to be the reason for high device efficiency. In Chapter 5 the effect of different substrate electrodes on the stability of PV devices based on CsSnI3:SnCl2 films is described. It is shown that the stability of thin films of B-g CsSnI3 perovskite towards oxidation in air depends strongly on the choice of substrate electrode and that unencapsulated devices using ITO or semi-transparent Au as the hole-extracting electrode, without an HTL, are more stable than those using an HTL. PV devices using ITO only as the hole-extracting electrode exhibit the highest stability, with a 30% reduction in efficiency only after 20 hours testing in air for the champion device. Chapter 6 describes an investigation of A and B site substitution in CsSnI3, with particular focus on Rb partial A-site substitution. It was found that increasing the Rb content reduced lm stability, but significantly increased device Voc due to an increase in the perovskite ionisation potential.

Automatic video surveillance has become one of the most active research areas in computer vision. Its applications are vast; these include security purposes, patient monitoring and law enforcement. Considering that millions of cameras operate all over the world, human surveillance is impractical for many reasons. Perhaps the most important reason is that strictly speaking, we require one person to monitor one camera. This monitoring is not only unrealistic but also inefficient because we cannot have a person 24/7 observing a scene. Even if that would be possible, fatigue and distractions might deter its efficiency. The main challenge of video surveillance is that it requires online processing (no-cumulative delay process) for practical scenario purposes. The reason is that the system’s response should be given immediately after the event occurred. If this time requirement is not satisfied, the system will end up warning the operators minutes or hours later. Then, the system’s response will be impractical for some events (e.g. crimes, accidents and fires) where the response times are critical. Although many methods have been developed for video surveillance, there is very little in terms of online-based methods. The lack of online approaches has been because there is a trade-off between accuracy in detecting events and computational complexity. The objective of this thesis is to minimise the gap of the speed-accuracy trade-off. To this end, this thesis proposes: (I) multi-source motion extraction to boost accuracy and expand the type of events to be detected, (II) extract few but high descriptive features via multi-scale extraction with perspective compensation, and (III) four fast binary-based video descriptors. The main findings of this thesis are as follows: First, multi-scaled perspective features reduce computational times meeting online requirements in abnormal event detection. Second, binary video features achieve competitive accuracy in action recognition compared with existing features while drastically outperform them in terms of computational complexity. In conclusion, first, by carefully selecting the spatio-temporal regions to process video data significantly improves accuracy and at the same time reduces computational times to detect abnormal events. Second, binary video features can compete with existing features by selecting a limited number of descriptive spatio-temporal symmetric regions. Finally, the findings of this thesis could benefit all those video applications that require real-time or online processing times.

For solid-state power devices, there exists need for a material with a higher band gap which will result in a higher critical electric field, improved power efficiency and thermal performance. This has resulted in the use of Silicon Carbide (SiC) as a serious alternative to Silicon for power devices. SiC trench MOSFETs have attracted major attention in recent years because of 1) lower on resistance by eliminating the JFET effect which exists in lateral MOSFETs, 2) higher channel density which lowers the threshold voltage and 3) reduction of the required surface area because of the vertical channel. These advantages allow faster switching speeds and the potential for a higher density of devices leading to more compact modules. This work was focused on fabrication of the first generation of 4H-SiC trench MOSFETs in Warwick University. Two main goals were achieved in this work: a comprehensive understanding of fabrication of trenches in 4H-SiC and fabrication of first generation of 4H-SiC trench MOSFET with mobility as high as 35.

Non-linearity and noise are two phenomena that are expected to be essential to future advanced technologies. Although largely abstained, in general, from introduction into current communication systems, the counter-intuitive phenomenon called Stochastic Resonance (SR) can be introduced into communication systems in an innovative form. Therefore, in this thesis, the most prominent dynamical system in the SR field, the double well potential, namely the over-damped Duffing equation with symmetric bistable potential, has been studied in order to reveal its signal processing capabilities for communication systems. Within this thesis, the double well potential was designed in order to detect a binary pulse amplitude modulated (BPAM) signal subject to a background noise. The bit-error-rate (BER) performance was enhanced by adding various resonant signals to the input. In addition, the eye patterns of system output indicated that, while decreasing BER, a resonant causes a strong fluctuation. It was eliminated by a use of two systems coupled in parallel, which provided further performance improvement. The results inferred that the double well potential performs filtering and modulation. Following that, the double well potential was designed as a lowpass filter by determining the DC gain and cut-off frequency. Through simulations, as a filter, its noise suppression performance was shown to be better than that of various orders of Butterworth filters. The analog and digital modulation capabilities of the double well potential have also been investigated. In order to clarify the relation between input signal and modulation parameters, the differential equation driving the output was solved, and thus the output was expressed as a function of modulation parameters. It was shown that the output is a multivariate analog modulated signal. In terms of digital modulation, the output of system processing a PAM signal has been interpreted by means of a Markov chain. The results indicated that this process consists of a convolutional coding and multidimensional modulation. In addition, the presence of noise induced coding was found. Finally, the system was designed to obtain a pulse width position modulated (PWPM) output. Throughout the project, detection, filtering, modulation and coding capabilities have been demonstrated, it has been concluded that the double well potential is an sophisticated signal processing tool.