The global electricity network has recently been experiencing a large scale integration of renewable energy sources, mainly photovoltaic and wind. This transformation is driven by the need for a reduction of carbon dioxide emissions, to limit greenhouse effect and mitigate global warming at the same time improving security of the supply. Large coal power plants are the main contributors of CO2 emissions, and electricity demand is constantly growing, especially in large urban/industrial areas. In this scenario, renewable energies are the only viable alternative to reduced environmental impact and carbon footprint of the electrical system. The main drawback of renewable energies is that they are usually generated far from where the energy is consumed. Typical examples in the UK are offshore wind farms, harvesting energy in the North Sea and delivering it to the mainland. Installing wind farms offshore gives higher wind speed and minimises the environmental impact, but might result in hundreds of kilometres separating the generator and the users. When distance increases, traditional and well-established AC transmission technology becomes unsustainable for its high energy loss. High Voltage DC (HVDC) is the technology enabling bulk power transmission over long distances (>600km for overhead cables, >40km for submarine cables), thanks to its higher efficiency and lower cost. Compared to AC power transmission, DC transmission is more complex, relying on Power Converter stations to transform from AC to DC at the wind farm side and back to AC when power is delivered to the mainland. Major issues in the design of converter stations for HVDC are size, weight, cost, efficiency, and manufacturing/maintenance. The basic problem is that these converters, when based on conventional technology, can be as large as a medium-sized industrial building and as heavy as 10000 tons for a typical 1GW installation. This poses two main challenges, at both ends of the HVDC link: 1.Offshore challenge: installing large and bulk converters offshore increases the cost of the platform, and reduces competitiveness of offshore wind. In addition, construction, commissioning and maintenance of the converter are both complex and expensive. 2.Onshore challenge: the converter onshore is often located in densely populated areas where energy is needed but land is expensive and limited. Also, environmental and visual landscape impact are a concern. This project will propose compact power conversion topologies for offshore and urban stations that have reduced size, weight, cost and environmental impact while maintaining adequate performances. In addition, the commissioning phase will be taken into account in the explored topologies, in order to increase modularity at system level and reduce construction efforts. The topologies will be discussed with key industry stakeholders and compared to standard state of art solutions, to identify the most attractive option, and the result of this trade off will feed into three work packages: design of the proposed converter, computer simulation and construction of a laboratory demonstrator to prove the feasibility and functionality of the proposed technology.

Monitoring the health of tribocontacts requires the study of friction, tribofilm integrity, and wear transitions. These challenge experimental tribologists to develop accurate methods for in-situ measurements and ideally continuous monitoring. Indirect measurements such as friction changes, sudden heating, changes in vibration or debris in the oil can detect severe wear transitions but cannot detect the subtle mechanistic changes which occur in unhealthy evolution of the contact. However, surface charge generated by tribocontacts and measured by single macro sensors, has detected tribological features such as tribofilm chemistry, adhesive wear, abrasive wear, phase transformations and wear debris but over large surfaces areas. This proposal, therefore, will miniaturise existing sensing technology, with embedded electronics to overcome signal to noise issues, and use arrayed sensors for augmented sensing, and machine learning. The sensor array /learning system would be trained to detect early evidence of lubricated contact decay from charge maps of the surface and allow better prediction of remaining useful life or, what corrective adjustment is needed in running conditions, to assure operational integrity.

The main focus of this project is to experimentally investigate and mathematically describe emergent properties of a large cellular system. A large cellular population is a complex dynamical system far from equilibrium, where macro-dynamics are driven by interactions and heterogeneity at the systems micro- or cell-level. Understanding exactly how microstate properties instigate and perpetuate emergent macroscopic phenomena is one of the fundamental challenges facing contemporary biology today. Quantifying such symbiotic relationships is at the heart of many scientific research endeavours. This broad scientific area covers an equally matched myriad of length scales, ranging from spontaneous symmetry breaking at the sub-atomic level through to galactic cluster formation at the cosmic scale. For the most part, formations of emergent configurations in these systems are intrinsically linked to non-linear interactions between the individual components that together constitute the complex system. It has been established that many of the confounding features of such systems can be adequately described through the application of statistical mechanics. The mathematical methodology can encapsulate and link macroscopic descriptions of the system to that of the microstate, allowing emergent ensemble behaviours to be quantified. Large cellular populations fulfil all necessary criteria to be considered a complex system (i.e. the cell being the systems microstate); constituent cells are vast number; cells are heterogeneous in physical, biological function; cell-cell and cell-environment interactions are inherently nonlinear. Adherence of the microstates to these criteria promotes the formation of emergent behaviour at the cellular population level; significant examples include embryo development, tissue regeneration during wound healing and the proliferation of metastatic diseases. However, application of statistical mechanics to describe and predict large-scale cellular systems have been hampered due to the fact that (i) such systems are in a state of non-equilibrium exhibiting vast heterogeneity across constituent microstates, simply averaging over ensemble variability results in distorted macroscopic system view and (ii) the ability to identify, track and quantify significant numbers of individuals within a cellular population to assess and account for microstate variability has been hindered by the availability of high-throughput microscopy platforms. Together these issues have obstructed application of statistical mechanics methods to elucidate upon the formation, function and stability of ensemble behaviour of a complex cellular system. The work presented as part of this EPSRC first grant application will address this current shortfall in scientific application and understanding. Recent advances in high-throughput microscopy present an opportunity to collate detailed information of microstate behaviour and allow development of mathematical models to describe the system. This interdisciplinary proposal seeks to unify contemporary biology, advanced imaging and statistical mathematics in order to measure and track the evolving interactions, dynamics and fate of >100,000 individual cells over extended periods. This databank will provide invaluable information, detailing microstate quantities such as morphology, biological function and spatial correlation and will further allow realisation of stochastic and master equation descriptions of the large-scale cellular system in question. Furthermore, this will ensure system variability is incorporated within models at the outset, providing robust linkage between the systems micro- to macro-levels and allowing sources of emergent phenomena to be more accurately described and predicted.

Future wireless systems are expected to constitute an ultra dense wireless network, which supports billions of smart wireless devices (or machines) to provide a wide varieties of services for smart homes, smart cities, smart transportation systems, smart healthcare, and smart environments, etc., in addition to supporting conventional human-initiated mobile communications. Therefore, the communication technologies employed in future wireless communication systems are expected to be capable of coping with highly diverse service requirements and communication environments, both of which also have time-varying nature. However, the legacy wireless systems, such as LTE/LTE-A, have been primarily designed for human-initiated mobile communications, which rely on strict synchronisation guaranteed by a substantial signalling overhead. Explicitly, due to this overhead legacy systems are inefficient for device-centric mMTC. Furthermore, they are unable to support the massive connectivity required by the future mMTC networks, where devices heavily contend for the limited resources available for communications. This project is proposed at the time, when myriads of smart wireless devices of different types are being deployed and connected via the Internet, which is expected to be the next revolution in the mobile ecosystem. To fulfil these objectives, a new design paradigm is required for supporting the massive number of wireless devices having diverse service requirements and unique traffic characteristics. In this project, we propose to meet the challenges of future mMTC by investigating and designing novel non-orthogonal multiple access, flexible duplexing, and adaptive coherent-noncoherent transmission schemes, as well as new waveforms that are tailored for the future mMTC systems. We aim for alleviating the strict synchronism demanded by the legacy wireless systems, and for significantly improving their capabilities, network performance as well as the lifetime of autonomous mMTC nodes. The novelties of this project are summarized as follows. 1. New non-orthogonal sparse code multiple access (SCMA) schemes will be developed for mMTC systems, where the number of devices exceeds the number of available resource-slots, resulting in an over-loaded or a generalized rank-deficient condition. 2. Novel multicarrier waveforms will be designed for future mMTC in order to maximize spectrum efficiency by minimizing the overhead for achieving synchronisation as well as for reducing the out-of-band radiation. 3. By jointly exploiting the resources available in the time, frequency and spatial domains, we will design noncoherent, partially-coherent and adaptive coherent-noncoherent transmission schemes, in order to strike the best possible trade-off among overhead reduction, energy and spectral efficiency, latency and implementation complexity in practical mMTC scenarios. 4. We will investigate the full potential of the multicarrier-division duplex (MDD) scheme and, especially, its applications to future mMTC by synergistically combining it with novel multicarrier waveforms, non-orthogonal SCMA techniques and other high-efficiency transmission schemes developed within the project. 5. Furthermore, the key techniques developed in the project will be prototyped and integrated into the 5G Innovation Centre (5GIC) test bed facilities at the University of Surrey. This will allow us to demonstrate the viability of our new design approaches, as well as to accelerate knowledge transfer and commercialisation. The proposed research will be conducted jointly by the 5GIC at the University of Surrey and Southampton Wireless (SW) at the University of Southampton, led by Xiao, Tafazolli, Yang & Hanzo. The research and commercial exploitation of the project will be further consolidated by our partnership with experienced academic and industrial partners.

Flexural transducer currently are only designed for operation in ambient atmospheric conditions, at frequencies of up to approximately 50 kHz, with a long wavelengths in fluids and therefore reduced measurement resolution in many cases. If we could find a way to increase the frequency range of operation of these devices, whilst at the same time creating new designs that could withstand high pressures and temperatures, a plethora of new applications will open up, in some cases enabling measurements to be made that could not otherwise be taken - that is what this project will do, establishing a world lead in this field of research of High Frequency Flexural Transducers. Techniques will be created that used the HiFFUTs for the non-destructive testing of low acoustic impedance materials such as aerospace composites, flow measurements and metrology in hostile environments. Flexural ultrasonic transducers (sometimes referred to as uni-morphs) operate through the action of the bending / flexing of a piezoelectric material that is attached to a passive material. This is exactly how an ultrasonic car parking sensor operates, and these devices operating at twice the maximum audible frequency of humans, of around 40kHz, have had a tremendous impact, particularly on the automotive sector. The key to the success of flexural transducers used in parking sensors lies in the fact that they are extremely sensitive and efficient, whilst at the same time they are relatively simple to construct and are extremely robust. Imagine the typical environment that these sensors have to survive in; high vibration, large fluctuations in operating temperature, corrosive, dirty and wet conditions - whilst operating at a low power with a high sensitivity. So what makes these flexural transducers attractive to the automotive sector, where there is high pressure to keep sensor costs low at the same time as the sensors being very reliable? The two key factors are that (1) the piezoelectric element is bonded to the inside of a metal cap and the rear of the cap is hermetically sealed, and (2) the flexing of the metal cap and thin piezoelectric element, either from piezoelectric excitation or the arrival of a pressure wave requires relatively little energy. There is currently a surprising lack of any published, rigorous scientific study on these types of small flexural transducers, even at low frequencies and nothing appears to have been attempted using these types of transducers in liquids or for non-destructive evaluation. The vibration characteristics of a HiFFUT are dependent on the combined response and interaction of all the sensor's components with the medium it operates within or upon. Usually the mechanical response of these transducers is dominated by the vibration behaviour of the passive flexing membrane of the transducer housing to which the piezoelectric is attached, rather than the thickness or diameter of the piezoelectric element bonded to the housing. There are related examples of MEMs based transducers that operate by a flexural membrane at higher frequencies such as Capacitive Micro-machined Ultrasonic Transducers and Piezoelectric Micro-machined Ultrasonic Transducers and whilst these are clearly elegant devices, there are clearly a number of significant advantages to the use of HiFFUTs in many industrial applications. The most useful modes of operation are probably the axisymmetric modes, which will generate axisymmetric wave fields and work will mainly focus on these, but there may be instances where an anisotropic wave field provides an advantage. Flexural transducers or HiFFUTs can also be driven at a number of axisymmetric harmonic modes or frequencies - using one transducer to cover a wide bandwidth, with each mode having a different directivity pattern will dramatically increase the depth and breadth of information that can be obtained. These transducers are going to find applications in a wide range of industrial application