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It was found when reviewing the ransomware detection research literature that almost no proposal provided enough detail on how the test data set was created, or sufficient description of its actual content, to allow it to be recreated by other researchers interested in reconstructing their environment and validating the research results. A modern cybersecurity mixed file data set called NapierOne is presented, primarily aimed at, but not limited to, ransomware detection and forensic analysis research. NapierOne was designed to address this deficiency in reproducibility and improve consistency by facilitating research replication and repeatability. The methodology used in the creation of this data set is also described in detail. The data set was inspired by the Govdocs1 data set and it is intended that NapierOne be used as a complement to this original data set.An investigation was performed with the goal of determining the common files types currently in use. No specific research was found that explicitly provided this information, so an alternative consensus approach was employed. This involved combining the findings from multiple sources of file type usage into an overall ranked list. After which 5000 real-world example files were gathered, and a specific data subset created, for each of the common file types identified. In some circumstances, multiple data subsets were created for a specific file type, each subset representing a specific characteristic for that file type. For example, there are multiple data subsets for the ZIP file type with each subset containing examples of a specific compression method. Ransomware execution tends to produce files that have high entropy, so examples of file types that naturally have this attribute are also present. The resulting entire data set comprises of nearly 100 separate data subsets divided between 44 distinct file types, resulting in almost 500,000 unique files in total. A description of the techniques used to gather the files for each file type is provided together with the actions that were performed on the files to confirm that they were of the highest quality and provided an accurate representation of their specific file type. Details are also provided on the content of the entire data set as well as instructions on how researchers can gain free and unlimited access to the final data set.While the data set was initially created to aid research in ransomware detection, it is sufficiently broad and diverse enough to allow for its application in many other areas of research that require a varied mixture of common real-world file examples. The NapierOne data set is an ongoing project and researchers are strongly encouraged to leverage this data set in their own research.

an archaeological excavation to fully record the Roman archaeological remains on the site was undertaken in accordance with a Written Scheme of Investigation submitted by RPS (Harrison 2021) on behalf of the developer. This work was carried out in accordance with the Chartered Institute for Archaeologists Standard and guidance for field evaluation (2020). The mitigation excavations revealed no evidence for the 1st and early 2nd century military phase evident to the north of Watling Street, which suggests that the road was the southern boundary of the military phase. The south-western corner of the 2nd century settlement at Uxacona was represented by three ditches: two, intercutting, aligned north-south, and a third aligned WSW-ENE. Like the area of settlement directly to the north of Watling Street, activity in the mitigation area also diminished in the mid-3rd to late 4th century, reflecting a demise in both Uxacona and its mansio. A short-lived well and several pits were recorded outside the enclosed area, but the paucity of external features corroborates previous geophysical interpretation that the settlement probably did not continue past the southern boundary of the scheduled area. Part of the site was truncated by a post-medieval quarry pit.

The area was evaluated by means of 100m of trial trenching, divided between five 20m by 1.8m trenches. Topsoil, former ploughsoils and demonstrably modern overburden were removed by an appropriate machine using a toothless bucket under direct archaeological supervision. Ground reduction was carried out in shallow spits until the uppermost archaeological horizon, or the geological natural was reached. This work was carried out in accordance with the Chartered Institute for Archaeologists Standard and guidance for field evaluation (2020) All trenches exhibited shallow furrows running NE-SW. One furrow (503) in Trench 5 was excavated and recorded to provide a record (Fig 6) and to retrieve dating evidence. An abraded rim sherd of either 14th C. Cannon Park ware or a local Bedworth ware was retrieved from a furrow in Trench 3. No significant archaeological deposits or finds were recorded in the trenches. The evaluation has established that significant archaeological remains will not be impacted by the proposed development.

A programme of archaeological monitoring and recording was undertaken at Upper Grove End Farm, Upper Brailes, Warwickshire, during the excavation of a new wildlife pond by a 8 tonne 360 tracked machine using a toothless bucket. This work revealed no archaeologically significant features or finds, suggesting that the site was just beyond the edge of the extent of the medieval village, and within the field system.

The Derbyshire Archaeological Journal, 129, 1-16, This paper applies a landscape modelling approach, based on the use of a Geographic Information System, to the positioning of the Early Neolithic timber longhouses at Lismore Fields, Buxton. By comparing the siting of the longhouses with both the physical and cultural landscape around them, and with other longhouse sites in Britain, it seeks to understand how the Early Neolithic people of the Peak District lived within their world.

An understanding of the blockage potential for an oil dominated system is an important step in moving from hydrate prevention to hydrate management. To better understand this problem a series of experiments were performed by varying the water cut, fluid velocity, and gas-liquid volume fraction using the ExxonMobil (XoM) flow loop in Houston, Texas, USA. The XoM large loop is a three pass, four inch internal diameter flow loop with a sliding vane pump capable of generating liquid velocities of up to 4 m/s. The systems that were studied include a range of water cuts from 5%-50% in a light crude oil (Conroe crude) and a gas phase of either pure methane for sI or 75% methane and 25% ethane which has sII as the thermodynamically stable phase. The results are compared with the hydrate plug prediction tool, CSMHyK, integrated into the multiphase flow simulator OLGA5®. The comparison between the model and the flow loop results serve as a basis for improving hydrate formation and plug prediction. In addition, the experimental variables that promote plug formation in the flow loop and how these may translate into the field are discussed.

The avoidance of hydrate blockages in deepwater subsea tiebacks presents a major technical challenge with severe implications for production, safety and cost. The successful prediction of when and where hydrate plugs form could lead to substantial reductions in the use of chemical inhibitors, and to corresponding savings in operational expenditure. The diffusivity of the gas hydrate former (methane) or the host molecule (water), through a hydrate film is a key property for such predictions of hydrate plug formation. In this paper, a novel application of Differential Scanning Calorimetry is described in which a hydrate film was allowed to grow at a hydrocarbon-water interface for different hold-times. By determining the change in mass of the hydrate film as a function of hold-time, an effective diffusivity could be inferred. The effect of the subcooling, and of the addition of a liquid hydrocarbon layer were also investigated. Finally, the transferability of these results to hydrate growth from water-in-oil emulsions is discussed.

Understanding when hydrates will nucleate has notable importance in the area of flow assurance. Attempts to model hydrate formation in subsea pipelines currently requires an arbitrary assignment of a nucleation subcooling. Previous studies showed that sII hydrate containing a model water-soluble former, tetrahydrofuran, would nucleate over a narrow temperature range of a few degrees with constant cooling. It is desirable to know if gas phase hydrate formers, which are typically more hydrophobic and hence have a very low solubility in water, also exhibit this nucleation behavior. In this study, differential scanning calorimetry has been applied to determine the hydrate nucleation point for gas phase hydrate formers. Constant cooling ramps and isothermal approaches were combined to explore the probability of hydrate nucleation. In the temperature ramping experiments, methane and xenon were used at various pressures and cooling rates. In both systems, hydrate nucleation occurred over a narrow temperature range (2-3°C). Using methane at lower pressures, ice nucleated before hydrate; whereas at higher pressures, hydrate formed first. A subcooling driving force of around 30°C was necessary for hydrate nucleation from both guest molecules. The cooling rates (0.5-3°C/min) did not show any statistically significant effect on the nucleation temperature for a given pressure. The isothermal method was used for a methane system with pure water and a water-in-West African crude emulsion. Two isotherms (-5 and -10°C) were used to determine nucleation time. In both systems, the time required for nucleation decreased with increased subcooling.

A Brain-Computer Interface (BCI) is a device that uses the brain activity of a person as an input to select desired outputs on a computer. BCIs that use surface electroencephalogram (EEG) recordings as their input are the least invasive but also suffer from a very low signal-to-noise ratio (SNR) due to the very low amplitude of the person’s brain activity and the presence of many signal artefacts and background noise. This can be compensated for by subjecting the signals to extensive signal processing, and by using stimuli to trigger a large but consistent change in the signal – these changes are called evoked potentials. The method used to stimulate the evoked potential, and introduce an element of conscious selection in order to allow the user’s intent to modify the evoked potential produced, is called the BCI paradigm. However, even with these additions the performance of BCIs used for assistive communication and control is still significantly below that of other assistive solutions, such as keypads or eye-tracking devices.\ud \ud This thesis examines the paradigm and signal processing components of BCIs and puts forward several methods meant to enhance BCIs’ performance and efficiency. Firstly, two novel signal processing methods based on Empirical Mode Decomposition (EMD) were developed and evaluated. EMD is a technique that divides any oscillating signal into groups of frequency harmonics, called Intrinsic Mode Functions (IMFs). Furthermore, by using Takens’ theorem, a single channel of EEG can be converted into a multi-temporal channel signal by transforming the channel into multiple snapshots of its signal content in time using a series of delay vectors. This signal can then be decomposed into IMFs using a multi-channel variation of EMD, called Multi-variate EMD (MEMD), which uses the spatial information from the signal’s neighbouring channels to inform its decomposition. In the case of a multi-temporal channel signal, this allows the temporal dynamics of the signal to be incorporated into the IMFs. This is called Temporal MEMD (T-MEMD). The second signal processing method based on EMD decomposed both the spatial and temporal channels simultaneously, allowing both spatial and temporal dynamics to be incorporated into the resulting IMFs. This is called Spatio-temporal MEMD (ST-MEMD). Both methods were applied to a large pre-recorded Motor Imagery BCI dataset along with EMD and MEMD for comparison. These results were also compared to those from other studies in the literature that had used the same dataset.\ud \ud T-MEMD performed with an average classification accuracy of 70.2%, performing on a par with EMD that had an average classification accuracy of 68.9%. Both ST-MEMD and MEMD outperformed them with ST-MEMD having an average classification accuracy of 73.6%, and MEMD having an average classification accuracy of 75.3%. The methods containing spatial dynamics, i.e. MEMD and ST-MEMD, outperformed those with only temporal dynamics, i.e. EMD and T-MEMD. The two methods with temporal dynamics each performed on a par with the non-temporal method that had the same level of spatial dynamics. This shows that only the presence of spatial dynamics resulted in a performance increase. This was concluded to be because the differences between the classes of motor-imagery are inherently spatial in nature, not temporal.\ud \ud Next a novel BCI paradigm was developed based on the standard Steady-state Somatosensory Evoked Potential (SSSEP) BCI paradigm. This paradigm uses a tactile stimulus applied to the skin at a certain frequency, generating a resonance signal in the brain’s activity. If two stimuli of different frequency are applied, two resonance signals will be present. However, if the user attends one stimulus over the other, its corresponding SSSEP will increase in amplitude. Unfortunately these changes in amplitude can be very minute. To counter this, a stimulus\ud amplitude and frequency of the vibrotactile stimuli. It was hypothesised that if the stimuli generator was constructed that could alter the were of the same frequency, but one’s amplitude was just below the user’s conscious level of perception and the other was above it, the changes in the SSSEP between classes would be the same as those between an SSSEP being generated and neutral EEG, with differences in α activity between the low-amplitude SSSEP and neutral activity due to the differences in the user’s level of concentration from attending the low-amplitude stimulus.\ud \ud The novel SSSEP BCI paradigm performed on a par with the standard paradigm with an average 61.8% classification accuracy over 16 participants, compared to an average 63.3% classification accuracy respectively, indicating that the hypothesis was false. However, the large presence of electro-magnetic interference (EMI) in the EEG recordings may have compromised the data. Many different noise suppression methods were applied to the stimulus device and the data, and whilst the EMI artefacts were reduced in magnitude they were not eliminated completely. Even with the noise the standard SSSEP stimulus paradigm performed on a par with studies that used the same paradigm, indicating that the results may not have been invalidated by the EMI.\ud \ud Overall the thesis shows that motor-imagery signals are inherently spatial in difference, and that the novel methods of T-MEMD and ST-MEMD may yet out-perform the existing methods of EMD and MEMD if applied to signals that are temporal in nature, such as functional Magnetic Resonance Imaging (fMRI). Whilst the novel SSSEP paradigm did not result in an increase in performance, it highlighted the impact of EMI from stimulus equipment on EEG recordings and potentially confirmed that the amplitude of SSEP stimuli is a minor factor in a BCI paradigm.