The Plymouth Student Scientist - Volume 10 - 2017
https://pearl.plymouth.ac.uk/handle/10026.1/12944
2024-03-28T13:53:18ZA glaciologic and palaeoclimatic reconstruction of Younger Dryas conditions using geomorphic evidence from selected sites in the Fforest Fawr, Brecon Beacons National Park
https://pearl.plymouth.ac.uk/handle/10026.1/14167
A glaciologic and palaeoclimatic reconstruction of Younger Dryas conditions using geomorphic evidence from selected sites in the Fforest Fawr, Brecon Beacons National Park
Irvine, H.
During the Younger Dryas the climate in southern Wales enabled topographically constrained glaciers to develop within high elevation areas of the Brecon Beacons. Previous studies in this area have attributed numerous basin-floor ridge systems to both glacial and non-glacial origins. An approach considering viability based upon reconstructed dynamics has been found to yield results comparable with contemporary analogues, reducing reliance upon subjective interpretation of field evidence. Due to the sensitivity of cirque glaciers to changes in climate, palaeoglacial modelling may provide insight into past environmental conditions. This study contributes to published literature by undertaking glaciologic and palaeoclimatic reconstructions at four previously uninvestigated sites in the Fforest Fawr, using a recently released ArcGIS toolbox. Geomorphic evidence at these sites was considered likely to be of Younger Dryas age due to similarity with landforms dated nearby. Modelled cirque glaciers at Fan Gyhirych, Blaen Senni, Fan Bwlch Chwyth and Craig Cwm-du occupied a total area of 0.335km2 at a calculated average Equilibrium Line Altitude of 496m ASL. The resulting palaeoclimatic reconstructions appear to suggest an environment with greater annual precipitation than today. Solar radiation modelling of the June-August ablation season indicates partial shading of all sites due to aspect and topography, aiding ice preservation by minimising surface mass loss. Analysis of the potential for mass balance contribution from avalanches and windblown snow accumulation was also considered, with Fan Bwlch Chwyth and Fan Gyhirych yielding high prevailing wind snowblow factors of 5.2 and 2.1 respectively. Finally, calculation of glaciological dynamics suggests relatively inactive yet viable glaciers to have existed at Fan Gyhirych, Fan Bwlch Chywth and Craig Cwm-du, while geomorphic features at Blaen Senni are rejected as being of glacial origin due to the dimensions of modelled ice extent.
2017-01-01T00:00:00ZA machine learning approach to the classification of phishing bot accounts within Twitter
https://pearl.plymouth.ac.uk/handle/10026.1/14166
A machine learning approach to the classification of phishing bot accounts within Twitter
Brake, C.
Social network bots are becoming an ever-greater threat to online users. Most studies carried out have looked at bots which generate a lot of tweets known as spam, as these are very common. In recent years research into the area of bots within Twitter has been carried out using machine learning to attempt to find patterns in these ac-counts to aide with detection. However, limited research has been carried out that focuses on a sub set of Twitter bots which are involved in phishing campaigns which tweet very little to avoid detection. In this project an application was developed that combines a variety of commercial tools with machine learning theory to allow a user to collect and analyse public Twitter data using a neural network. The focus of the project is to try and find patterns in these phishing bots’ properties and to use the data collected to train a neural network to recognise these patterns and detect bots. A Twit-ter crawler was developed that harvests data from the Twitter API and stores it in a graph database. The data is then formatted and normalised by a pre-processor mod-ule which is then fed into a neural network. The neural network evaluates the data and creates predictions based on what it has previously learnt, these predictions are then displayed in a graph format within the browser. Experimental results have shown that there is a pattern in the properties of an account, and tests showed a correlation in the friend to follower ratio of bot accounts. With this pattern and other properties of an account, a neural network has been trained to detect bot accounts, with tests showing the neural being able to make predictions for an account with an accuracy of 92%. Whilst these results are still experimental the project has proven that is it possible to detect bots within Twitter using just the properties of an account.
2017-01-01T00:00:00ZGenetic optimisations for satisfiability and Ramsey theory
https://pearl.plymouth.ac.uk/handle/10026.1/14165
Genetic optimisations for satisfiability and Ramsey theory
Barnes, A.
The art of using evolutionary mechanisms for identifying satisfiability has produced a range of efficient solutions to this otherwise computationally challenging problem. Since their first use these evolutionary methods have been changed and adapted to produce increasingly efficient solutions. This paper introduces two unique alternatives to the optimisation of these methods, the first through the introduction of alternative mutation operators and the second through utilizing a grammatical encoding which has been proven to improve neuroevolution. The goal of this paper is to identify whether these two alternatives are candidates for future investigation in improving evolutionary satisfiability solvers.
2017-01-01T00:00:00ZUnderstanding the experiences of people with Acquired Brain Injury and their interactions with outside services
https://pearl.plymouth.ac.uk/handle/10026.1/14164
Understanding the experiences of people with Acquired Brain Injury and their interactions with outside services
Odumuyiwa, T.
Previous research has focused on Acquired Brain Injury (ABI) regarding the cognitive, behavioural, psychological and social effects, and the outcomes and implications this has had in different areas of people’s lives. However, there has been limited research exploring the existing relationship between individuals with ABI and community service providers. Therefore, the current study’s objective was to understand the experiences that those with ABI have had of community services and to recognise the extent to which they believed that these services understand their difficulties and needs. An interpretative phenomenological approach was used to allow the participants to reflect on the areas in which they believed were most important to their subjective experiences as a person with ABI, family member related to someone with ABI, or as a professional who had interacted with people with ABI in their role. Eight participants were recruited (two professionals, two individuals with ABI and four family members of individuals with ABI) and took part in semi-structured interviews. Five super-ordinate themes were identified following analysis of the transcripts 1) Hidden disabilities, 2) Knowledge and understanding, 3) Impact of ABI, 4) Access to services, and 5) Safeguarding. Several sub-themes within each superordinate theme were also identified. The findings from the study were consistent with previous research literature, and identified areas that could be improved.
2017-01-01T00:00:00Z