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Megaripple Dynamics On A Dissipative Sandy Beach, Jon Miles, Antony Thorpe, Paul Russell, Gerd Masselink Jan 2014

Megaripple Dynamics On A Dissipative Sandy Beach, Jon Miles, Antony Thorpe, Paul Russell, Gerd Masselink

School of Engineering, Computing and Mathematics

No abstract provided.


A Novel Real-Time Non-Linear Wavelet-Based Model Predictive Controller For A Coupled Tank System, Kayode Owa, Sanjay Sharma, Robert Sutton Jan 2014

A Novel Real-Time Non-Linear Wavelet-Based Model Predictive Controller For A Coupled Tank System, Kayode Owa, Sanjay Sharma, Robert Sutton

School of Engineering, Computing and Mathematics

This article presents the design, simulation and real-time implementation of a constrained non-linear model predictive controller for a coupled tank system. A novel wavelet-based function neural network model and a genetic algorithm online non-linear real-time optimisation approach were used in the non-linear model predictive controller strategy. A coupled tank system, which resembles operations in many chemical processes, is complex and has inherent non-linearity, and hence, controlling such system is a challenging task. Particularly important is low-level control where often instability and oscillatory responses are observed. This article designs a wavelet neural network with high predicting precision and time–frequency localisation characteristics …


Thinking In Circuits: Toward Neurobiological Explanation In Cognitive Neuroscience., Friedemann Pulvermüller, Max Garagnani, Thomas Wennekers Jan 2014

Thinking In Circuits: Toward Neurobiological Explanation In Cognitive Neuroscience., Friedemann Pulvermüller, Max Garagnani, Thomas Wennekers

School of Engineering, Computing and Mathematics

Cognitive theory has decomposed human mental abilities into cognitive (sub) systems, and cognitive neuroscience succeeded in disclosing a host of relationships between cognitive systems and specific structures of the human brain. However, an explanation of why specific functions are located in specific brain loci had still been missing, along with a neurobiological model that makes concrete the neuronal circuits that carry thoughts and meaning. Brain theory, in particular the Hebb-inspired neurocybernetic proposals by Braitenberg, now offers an avenue toward explaining brain-mind relationships and to spell out cognition in terms of neuron circuits in a neuromechanistic sense. Central to this endeavor …


Learning To Pronounce First Words In Three Languages: An Investigation Of Caregiver And Infant Behavior Using A Computational Model Of An Infant., Ian S. Howard, Piers Messum Jan 2014

Learning To Pronounce First Words In Three Languages: An Investigation Of Caregiver And Infant Behavior Using A Computational Model Of An Infant., Ian S. Howard, Piers Messum

School of Engineering, Computing and Mathematics

Words are made up of speech sounds. Almost all accounts of child speech development assume that children learn the pronunciation of first language (L1) speech sounds by imitation, most claiming that the child performs some kind of auditory matching to the elements of ambient speech. However, there is evidence to support an alternative account and we investigate the non-imitative child behavior and well-attested caregiver behavior that this account posits using Elija, a computational model of an infant. Through unsupervised active learning, Elija began by discovering motor patterns, which produced sounds. In separate interaction experiments, native speakers of English, French and …


Techniques For Production Of Large Area Graphene For Electronic And Sensor Device Applications, B Li, G Pan, Sa Awan, N Avent Jan 2014

Techniques For Production Of Large Area Graphene For Electronic And Sensor Device Applications, B Li, G Pan, Sa Awan, N Avent

School of Engineering, Computing and Mathematics

AbstractHere we review commonly used techniques for the production of large area and high quality graphene to meet the requirements of industrial applications, including epitaxial growth on SiC, chemical vapour deposition (CVD) on transition metals and growth from solid carbon source. The review makes a comparison of the growth mechanisms, quality (such as mobility and homogeneity) and properties of the resultant graphene, limitations and the prospect of each production method. A particular focus of the review is on direct (transfer free) growth on dielectric substrate as this is potentially one of the promising techniques for graphene production which can readily …


On The Electrodynamics Of Neural Networks, S Rodrigues, Pb Graben Jan 2014

On The Electrodynamics Of Neural Networks, S Rodrigues, Pb Graben

School of Engineering, Computing and Mathematics

We present a microscopic approach for the coupling of cortical activity, as resulting from proper dipole currents of pyramidal neurons, to the electromagnetic field in extracellular fluid in presence of diffusion and Ohmic conduction. Starting from a full-fledged three-compartment model of a single pyramidal neuron, including shunting and dendritic propagation, we derive an observation model for dendritic dipole currents in extracellular space and thereby for the dendritic field potential that contributes to the local field potential of a neural population. Under reasonable simplifications, we then derive a leaky integrate-and-fire model for the dynamics of a neural network, which facilitates comparison …


Toward A Self-Organizing Pre-Symbolic Neural Model Representing Sensorimotor Primitives, J Zhong, A Cangelosi, S Wermter Jan 2014

Toward A Self-Organizing Pre-Symbolic Neural Model Representing Sensorimotor Primitives, J Zhong, A Cangelosi, S Wermter

School of Engineering, Computing and Mathematics

The acquisition of symbolic and linguistic representations of sensorimotor behavior is a cognitive process performed by an agent when it is executing and/or observing own and others' actions. According to Piaget's theory of cognitive development, these representations develop during the sensorimotor stage and the pre-operational stage. We propose a model that relates the conceptualization of the higher-level information from visual stimuli to the development of ventral/dorsal visual streams. This model employs neural network architecture incorporating a predictive sensory module based on an RNNPB (Recurrent Neural Network with Parametric Biases) and a horizontal product model. We exemplify this model through a …


Capture Of Fixation By Rotational Flow; A Deterministic Hypothesis Regarding Scaling And Stochasticity In Fixational Eye Movements, Nm Wilkinson, G Metta Jan 2014

Capture Of Fixation By Rotational Flow; A Deterministic Hypothesis Regarding Scaling And Stochasticity In Fixational Eye Movements, Nm Wilkinson, G Metta

School of Engineering, Computing and Mathematics

Visual scan paths exhibit complex, stochastic dynamics. Even during visual fixation, the eye is in constant motion. Fixational drift and tremor are thought to reflect fluctuations in the persistent neural activity of neural integrators in the oculomotor brainstem, which integrate sequences of transient saccadic velocity signals into a short term memory of eye position. Despite intensive research and much progress, the precise mechanisms by which oculomotor posture is maintained remain elusive. Drift exhibits a stochastic statistical profile which has been modeled using random walk formalisms. Tremor is widely dismissed as noise. Here we focus on the dynamical profile of fixational …


Bilateral Gain Control; An “Innate Predisposition” For All Sorts Of Things, N Wilkinson, G Metta Jan 2014

Bilateral Gain Control; An “Innate Predisposition” For All Sorts Of Things, N Wilkinson, G Metta

School of Engineering, Computing and Mathematics

Empirical studies have revealed remarkable perceptual organization in neonates. Newborn behavioral distinctions have often been interpreted as implying functionally specific modular adaptations, and are widely cited as evidence supporting the nativist agenda. In this theoretical paper, we approach newborn perception and attention from an embodied, developmental perspective. At the mechanistic level, we argue that a generative mechanism based on mutual gain control between bilaterally corresponding points may underly a number of functionally defined "innate predispositions" related to spatial-configural perception. At the computational level, bilateral gain control implements beamforming, which enables spatial-configural tuning at the front end sampling stage. At the …


Official Statistics Data Integration Using Copulas, L Dalla Valle Jan 2014

Official Statistics Data Integration Using Copulas, L Dalla Valle

School of Engineering, Computing and Mathematics

No abstract provided.


The Antibacterial Effects Of Silver, Titanium Dioxide And Silica Dioxide Nanoparticles Compared To The Dental Disinfectant Chlorhexidine On Streptococcus Mutans Using A Suite Of Bioassays., Alexandros Besinis, Peralta T De, Richard D. Handy Jan 2014

The Antibacterial Effects Of Silver, Titanium Dioxide And Silica Dioxide Nanoparticles Compared To The Dental Disinfectant Chlorhexidine On Streptococcus Mutans Using A Suite Of Bioassays., Alexandros Besinis, Peralta T De, Richard D. Handy

School of Engineering, Computing and Mathematics

Metal-containing nanomaterials have the potential to be used in dentistry for infection control, but little is known about their antibacterial properties. This study investigated the toxicity of silver (Ag), titanium dioxide and silica nanoparticles (NPs) against the oral pathogenic species of Streptococcus mutans, compared to the routine disinfectant, chlorhexidine. The bacteria were assessed using the minimum inhibitory concentration assay for growth, fluorescent staining for live/dead cells, and measurements of lactate. All the assays showed that Ag NPs had the strongest antibacterial activity of the NPs tested, with bacterial growth also being 25-fold lower than that in chlorhexidine. The survival rate …


Application Of A Novel Decision Support System To Assess And Manage Coastal Flood Risk In The Teign Estuary, Uk., Santamaria R Gonzalez, D Simmonds, B Zanuttigh, D Reeve, R Nicholls, R Thompson, S Pan, J Horrillo-Caraballo, S Hoggart, S Hanson, E Penning-Rowsell, A Fox, M Hanley Jan 2014

Application Of A Novel Decision Support System To Assess And Manage Coastal Flood Risk In The Teign Estuary, Uk., Santamaria R Gonzalez, D Simmonds, B Zanuttigh, D Reeve, R Nicholls, R Thompson, S Pan, J Horrillo-Caraballo, S Hoggart, S Hanson, E Penning-Rowsell, A Fox, M Hanley

School of Engineering, Computing and Mathematics

This paper demonstrates the application of a Decision Support System (DSS) developed for decision makers and stakeholders to manage and raise awareness of coastal flood risk. The DSS is a GIS-based framework that predicts flooding consequences and is structured around the Source Pathway Receptor Consequence (SPRC) model. The DSS draws together points of view from engineering, ecology and socio-economics, allowing the comparative assessment of the consequences of a range of management interventions. The utility of the tool is demonstrated through application to an estuary field site - the Teign estuary in UK. Vulnerability maps, generated by the DSS for pre-set …


Non Invasive Investigation Of Sensorimotor Control For Future Development Of Brain-Machine-Interface (Bmi), Leo Tomasevic Jan 2014

Non Invasive Investigation Of Sensorimotor Control For Future Development Of Brain-Machine-Interface (Bmi), Leo Tomasevic

School of Engineering, Computing and Mathematics Theses

My thesis focuses on describing novel functional connectivity properties of the sensorimotor system that are of potential interest in the field of brain-machine interface. In particular, I have investigated how the connectivity changes as a consequence of either pathologic conditions or spontaneous fluctuations of the brain's internal state. An ad-hoc electronic device has been developed to implement the appropriate experimental settings. First, the functional communication among sensorimotor primary nodes was investigated in multiple sclerosis patients afflicted by persistent fatigue. I selected this condition, for which there is no effective pharmacological treatment, since existing literature links this type of fatigue to …


Peripersonal Space In The Humanoid Robot Icub, Salomón Ramírez Contla Jan 2014

Peripersonal Space In The Humanoid Robot Icub, Salomón Ramírez Contla

School of Engineering, Computing and Mathematics Theses

Developing behaviours for interaction with objects close to the body is a primary goal for any organism to survive in the world. Being able to develop such behaviours will be an essential feature in autonomous humanoid robots in order to improve their integration into human environments. Adaptable spatial abilities will make robots safer and improve their social skills, human-robot and robot-robot collaboration abilities. This work investigated how a humanoid robot can explore and create action-based representations of its peripersonal space, the region immediately surrounding the body where reaching is possible without location displacement. It presents three empirical studies based on …


Towards The Grounding Of Abstract Categories In Cognitive Robots, Francesca Stramandinoli Jan 2014

Towards The Grounding Of Abstract Categories In Cognitive Robots, Francesca Stramandinoli

School of Engineering, Computing and Mathematics Theses

The grounding of language in humanoid robots is a fundamental problem, especially in social scenarios which involve the interaction of robots with human beings. Indeed, natural language represents the most natural interface for humans to interact and exchange information about concrete entities like KNIFE, HAMMER and abstract concepts such as MAKE, USE. This research domain is very important not only for the advances that it can produce in the design of human-robot communication systems, but also for the implication that it can have on cognitive science. Abstract words are used in daily conversations among people to describe events and situations …


Gpu Computing For Cognitive Robotics, Martin Peniak Jan 2014

Gpu Computing For Cognitive Robotics, Martin Peniak

School of Engineering, Computing and Mathematics Theses

This thesis presents the first investigation of the impact of GPU computing on cognitive robotics by providing a series of novel experiments in the area of action and language acquisition in humanoid robots and computer vision. Cognitive robotics is concerned with endowing robots with high-level cognitive capabilities to enable the achievement of complex goals in complex environments. Reaching the ultimate goal of developing cognitive robots will require tremendous amounts of computational power, which was until recently provided mostly by standard CPU processors. CPU cores are optimised for serial code execution at the expense of parallel execution, which renders them relatively …


Non-Linear Model Predictive Control Strategies For Process Plants Using Soft Computing Approaches, Kayode Olayemi Owa Jan 2014

Non-Linear Model Predictive Control Strategies For Process Plants Using Soft Computing Approaches, Kayode Olayemi Owa

School of Engineering, Computing and Mathematics Theses

The developments of advanced non-linear control strategies have attracted a considerable research interests over the past decades especially in process control. Rather than an absolute reliance on mathematical models of process plants which often brings discrepancies especially owing to design errors and equipment degradation, non-linear models are however required because they provide improved prediction capabilities but they are very difficult to derive. In addition, the derivation of the global optimal solution gets more difficult especially when multivariable and non-linear systems are involved. Hence, this research investigates soft computing techniques for the implementation of a novel real time constrained non-linear model …


Familial Strife On The Seashore: Aggression Increases With Relatedness In The Sea Anemone Actinia Equina., Nicola L. Foster, Mark Briffa Jan 2014

Familial Strife On The Seashore: Aggression Increases With Relatedness In The Sea Anemone Actinia Equina., Nicola L. Foster, Mark Briffa

School of Biological and Marine Sciences

Pairwise contests occur when two individuals compete directly over ownership of an indivisible resource. Contests vary in the degree of escalation, some encounters being settled through non-injurious behaviour while others are only resolved after dangerous fighting. Here, we investigate the role of relatedness, assessed using AFLP analysis, on the occurrence of stinging during staged contests in the beadlet sea anemone Actinia equina. Contrary to our expectations, we found that the chance of stinging, and hence the chance of inflicting damage, increased with the degree of relatedness between the two opponents. This result may be explained by the negative relationship between …


Variable Response Of Three Trifolium Repens Ecotypes To Soil Flooding By Seawater., Anissia C. White, Timothy D. Colmer, Greg R. Cawthray, Mick E. Hanley Jan 2014

Variable Response Of Three Trifolium Repens Ecotypes To Soil Flooding By Seawater., Anissia C. White, Timothy D. Colmer, Greg R. Cawthray, Mick E. Hanley

School of Biological and Marine Sciences

BACKGROUND AND AIMS: Despite concerns about the impact of rising sea levels and storm surge events on coastal ecosystems, there is remarkably little information on the response of terrestrial coastal plant species to seawater inundation. The aim of this study was to elucidate responses of a glycophyte (white clover, Trifolium repens) to short-duration soil flooding by seawater and recovery following leaching of salts. METHODS: Using plants cultivated from parent ecotypes collected from a natural soil salinity gradient, the impact of short-duration seawater soil flooding (8 or 24 h) on short-term changes in leaf salt ion and organic solute concentrations was …


A Generalized Equilibriummodel For Predicting Daily To Interannual Shoreline Response, Kristen D. Splinter, Ian L. Turner, Mark A. Davidson, Patrick Barnard, Bruno Castelle, Joan Oltman-Shay Jan 2014

A Generalized Equilibriummodel For Predicting Daily To Interannual Shoreline Response, Kristen D. Splinter, Ian L. Turner, Mark A. Davidson, Patrick Barnard, Bruno Castelle, Joan Oltman-Shay

School of Biological and Marine Sciences

No abstract provided.


Factors Affecting The Levels Of Protection Transferred From Mother To Offspring Following Immune Challenge, Christina M. Coakley, Vincent Staszewski, Katherine A. Herborn, Emma J.A. Cunningham Jan 2014

Factors Affecting The Levels Of Protection Transferred From Mother To Offspring Following Immune Challenge, Christina M. Coakley, Vincent Staszewski, Katherine A. Herborn, Emma J.A. Cunningham

School of Biological and Marine Sciences

No abstract provided.


Minimal Effects Of Waterborne Exposure To Single-Walled Carbon Nanotubes On Behaviour And Physiology Of Juvenile Rainbow Trout (Oncorhynchus Mykiss)., D Boyle, Je Fox, Jm Akerman, Ka Sloman, Tb Henry, Rd Handy Jan 2014

Minimal Effects Of Waterborne Exposure To Single-Walled Carbon Nanotubes On Behaviour And Physiology Of Juvenile Rainbow Trout (Oncorhynchus Mykiss)., D Boyle, Je Fox, Jm Akerman, Ka Sloman, Tb Henry, Rd Handy

School of Biological and Marine Sciences

Fish behaviours are often considered to be sensitive endpoints of waterborne contaminants, but little attention has been given to engineered nanomaterials. The present study aimed to determine the locomotor and social behaviours of rainbow trout (Oncorhynchus mykiss) during waterborne exposure to single-walled carbon nanotubes (SWCNTs), and to ascertain the physiological basis for any observed effects. Dispersed stock suspensions of SWCNTs were prepared by stirring in sodium dodecyl sulphate (SDS), an anionic surfactant, on an equal w/w basis. Trout were exposed to control (no SWCNT or SDS), 0.25 mg L(-1) SDS (dispersant control), or 0.25 mg L(-1) of SWCNT for 10 …


Uptake Epithelia Behave In A Cell-Centric And Not Systems Homeostatic Manner In Response To Zinc Depletion And Supplementation, D Zheng, Gp Feeney, Rd Handy, C Hogstrand, P Kille Jan 2014

Uptake Epithelia Behave In A Cell-Centric And Not Systems Homeostatic Manner In Response To Zinc Depletion And Supplementation, D Zheng, Gp Feeney, Rd Handy, C Hogstrand, P Kille

School of Biological and Marine Sciences

No abstract provided.


Effects Of Silver Nanoparticles (Nm-300k) On Lumbricus Rubellus Earthworms And Particle Characterization In Relevant Test Matrices Including Soil, Der Ploeg Mjc Van, Rd Handy, Pl Waalewijn-Kool, Den Berg Jhj Van, Zeh Rivera, J Bovenschen, B Molleman, Jm Baveco, P Tromp, Rjb Peters, Gf Koopmans, Imcm Rietjens, Den Brink Nw Van Jan 2014

Effects Of Silver Nanoparticles (Nm-300k) On Lumbricus Rubellus Earthworms And Particle Characterization In Relevant Test Matrices Including Soil, Der Ploeg Mjc Van, Rd Handy, Pl Waalewijn-Kool, Den Berg Jhj Van, Zeh Rivera, J Bovenschen, B Molleman, Jm Baveco, P Tromp, Rjb Peters, Gf Koopmans, Imcm Rietjens, Den Brink Nw Van

School of Biological and Marine Sciences

No abstract provided.


The Deep Sea Is A Major Sink For Microplastic Debris, Lucy C. Woodall, Anna Sanchez-Vidal, Miquel Canals, Gordon L.J. Paterson, Rachel Coppock, Victoria Sleight, Antonio Calafat, Alex D. Rogers, Bhavani E. Narayanaswamy, Richard C. Thompson Jan 2014

The Deep Sea Is A Major Sink For Microplastic Debris, Lucy C. Woodall, Anna Sanchez-Vidal, Miquel Canals, Gordon L.J. Paterson, Rachel Coppock, Victoria Sleight, Antonio Calafat, Alex D. Rogers, Bhavani E. Narayanaswamy, Richard C. Thompson

School of Biological and Marine Sciences

Marine debris, mostly consisting of plastic, is a global problem, negatively impacting wildlife, tourism and shipping. However, despite the durability of plastic, and the exponential increase in its production, monitoring data show limited evidence of concomitant increasing concentrations in marine habitats. There appears to be a considerable proportion of the manufactured plastic that is unaccounted for in surveys tracking the fate of environmental plastics. Even the discovery of widespread accumulation of microscopic fragments (microplastics) in oceanic gyres and shallow water sediments is unable to explain the missing fraction. Here, we show that deep-sea sediments are a likely sink for microplastics. …


Evaluation Of The Microbial Community, Acidity And Proximate Composition Of Akamu, A Fermented Maize Food, Patience C. Obinna-Echem, Victor Kuri, Jane Beal Jan 2014

Evaluation Of The Microbial Community, Acidity And Proximate Composition Of Akamu, A Fermented Maize Food, Patience C. Obinna-Echem, Victor Kuri, Jane Beal

School of Biological and Marine Sciences

No abstract provided.


A Step-Wise Process Of Decision-Making Under Uncertainty When Implementing Environmental Policy, Am Knights, F Culhane, Ss Hussain, Kn Papadopoulou, Et Al Jan 2014

A Step-Wise Process Of Decision-Making Under Uncertainty When Implementing Environmental Policy, Am Knights, F Culhane, Ss Hussain, Kn Papadopoulou, Et Al

School of Biological and Marine Sciences

An ecosystem approach forms the basis of many recent environmental policies. The underlying concept states that decision-makers must consider the environmental, social and economic costs and benefits in the course of deciding whether to implement a management action. Decision-making can be undermined by uncertainty. Here, we discuss potential sources of uncertainty and their effect on an ecosystem approach-driven environmental policy, the factors affecting the choice and potential for management actions to achieve their objectives, the challenges associated with setting realistic and achievable targets, and how we can prioritise management of detrimental activities. We also consider how human challenges such as …


Observations Of Bedforms On A Dissipative Macrotidal Beach, Jon Miles, Antony Thorpe, Paul Russell, Gerd Masselink Jan 2014

Observations Of Bedforms On A Dissipative Macrotidal Beach, Jon Miles, Antony Thorpe, Paul Russell, Gerd Masselink

School of Engineering, Computing and Mathematics

No abstract provided.


Non-Linear Control Algorithms For An Unmanned Surface Vehicle, Sanjay K. Sharma, Robert Sutton, Amit Motwani, Andy Annamalai Jan 2014

Non-Linear Control Algorithms For An Unmanned Surface Vehicle, Sanjay K. Sharma, Robert Sutton, Amit Motwani, Andy Annamalai

School of Engineering, Computing and Mathematics

No abstract provided.


Cadmium Contamination Of Agricultural Soils And Crops Resulting From Sphalerite Weathering., T. C. Robson, C. B. Braungardt, J. Rieuwerts, P. Worsfold Jan 2014

Cadmium Contamination Of Agricultural Soils And Crops Resulting From Sphalerite Weathering., T. C. Robson, C. B. Braungardt, J. Rieuwerts, P. Worsfold

School of Geography, Earth and Environmental Sciences

The biogeochemistry and bioavailability of cadmium, released during sphalerite weathering in soils, were investigated under contrasting agricultural scenarios to assess health risks associated with sphalerite dust transport to productive soils from mining. Laboratory experiments (365 d) on temperate and sub-tropical soils amended with sphalerite (<63 μm, 0.92 wt.% Cd) showed continuous, slow dissolution (0.6-1.2% y(-1)). Wheat grown in spiked temperate soil accumulated ≈38% (29 μmol kg(-1)) of the liberated Cd, exceeding food safety limits. In contrast, rice grown in flooded sub-tropical soil accumulated far less Cd (0.60 μmol kg(-1)) due to neutral soil pH and Cd bioavailability was possibly also controlled by secondary sulfide formation. The results demonstrate long-term release of Cd to soil porewaters during sphalerite weathering. Under oxic conditions, Cd may be sufficiently bioavailable to contaminate crops destined for human consumption; however flooded rice production limits the impact of sphalerite contamination.