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Item Open Access Defence and Security Doctoral Symposium Flyer 2020(Cranfield University, 2020-07-24 10:38) Cranfield UniversityFlyer promoting the Defence and Security Doctoral Symposium 2020.Item Open Access Breast cancer at the micrometre scale(Cranfield University, 2020-11-27 09:28) Gosling, SarahMicrocalcifications are deposits of calcium phosphate commonly found in association with some types of breast cancer. Calcifications are usually detected as bright white spots on a mammogram. Diagnosis of some breast diseases is linked to the morphology and distribution of microcalcifications, but these deposits are rarely investigated as individual entities.Multiple techniques have been used to investigate individual calcifications, including histological staining (H&E), scanning electron microscopy (SEM), elemental analysis (EDS) and x-ray diffraction (XRD). Together, these techniques allow a better understanding of the structure of the crystalline and tissue elements of breast calcifications at the micrometre scale, which may provide an insight in their formation mechanisms and possible functions. Ultimately, deciphering calcification chemistry could lead to their use as novel prognostic markers for breast disease.Item Open Access Reflections and Their Real Space Significance(Cranfield University, 2020-11-27 10:01) Arnold, EmilyBone is a complex composite material made up of three main components, the most abundant of which is the mineral hydroxyapatite. Within many species, hydroxyapatite naturally occurs as a nanocrystalline material, making accurate analysis difficult. Brilliant X-ray sources are used to allow measurement of a much wider range of angular data (from Q = 0.05 to 60 Å-1) than a traditional laboratory X-ray diffractometer (from Q = 0.1 to 8 Å-1). Shown here is diffraction data collected at Diamond Light Source on the dedicated total scattering beamline I15-1. Debye-Scherrer rings can be seen, allowing measurement of crystallographic parameters within reciprocal space. Shadows are seen from the sample changer and an additional detector. This beamline allows for the observation of local coordination of atoms from 0.1nm to 5 nm (through pair distribution function analysis) while simultaneously measuring average crystallite structure.Item Open Access Structure of an Insensitive High Explosive formulation under a microscope(Cranfield University, 2020-11-27 10:07) Gutierrez-Carazo, EncinaIMX-104 is an Insensitive High Explosive containing a mixture of 3-Nitro-1,2,4-triazol-5-one (NTO), 2,4- dinitroanisole (DNAN) and cyclotrimethylenetrinitramine (RDX). Due to its novelty, little is known about its potential toxicity and persistence in the environment and which has raised questions regarding its behaviour.Small flakes were placed under a Leica DM LM microscope to observe their microscopic structure and investigate the formulation process. The picture was taken using a ten times lense (10x) and reflected light. The scale shows the size of the flakes (in mm) and the fragments in focus were approximately 70 µm.Item Open Access Capturing blast impact on helmets(Cranfield University, 2020-11-27 10:21) Bloodworth-Race, SusieWhen shielded from the fireball and fragmentation of an explosion, the blastwave can still cause multiple injuries, with increasing prevalence of Traumatic Brain Injury (TBI) noticed amongst survivors. Relatively low peak overpressures can result in Blast-Induced Mild TBI (bTBI), with significant deterioration in mental health manifesting as anxiety, behavioural changes, even loss of fine motor control, symptoms which can often be confused with Post Traumatic Stress Disorder (PTSD).The image shows a helmet blast impact from a compressed air shocktube, the resulting movement of head and helmet captured with high speed video. The moment of impact can be seen in the top sector with the shockwave captured as a vertical band of compressed air just behind the front of the head. The helmet is lifted, rotated backwards, held by the chinstrap and bounced back down onto the head, resulting in multiple possible mechanisms for bTBI.Item Open Access The Utility of Gait in Forensic Human Identification: An Empirical Investigation Using Biomechanical and Anthropological Principals(Cranfield University, 2020-11-27 12:06) Macoveciuc, IoanaForensic gait analysis is generally defined as the analysis of walking features of individuals from video footage, to assist in criminal investigations. Although an attractive approach to detecting suspects since data can be collected from a distance without their knowledge (e.g. from public CCTV cameras), this field of study currently lacks validation and quality standards not only due to insufficient research, but also because certain scientific foundations, such as the assumption of gait uniqueness, have not been adequately investigated. To test the scientific basis of this premise, a suitable dataset replicating an ideal forensic gait analysis scenario was compiled from the Karlsruhe Institute of Technology (Germany) database. Biomechanical analyses (i.e. joint angles) of human walking motion (i.e. gait cycles) in the left and right shoulder, elbow, hip, knee, and ankle joints of twenty participants was conducted using the R program. The purpose of these analyses was to investigate the degree to which differences between walking activities of the same participant (i.e. intraindividual variation) impact differences amongst participants (i.e. interindividual variation), according to the following aims: (1) to better understand the relationship between form (anatomy) and function (physiology) of human gait, (2) to investigate the basis of gait uniqueness by examining similarities and differences in joint angles, and (3) to build upon current theoretical foundations of gait-based human identification. The findings indicate different degrees of gait asymmetry given anatomical body region and gait sub-phase (i.e. component of a given cycle), thereby challenging previous methods employing interchangeable use of gait data irrespective of body side, and the use of ‘average’ gait cycles to represent the gait of an individual irrespective of body side. Furthermore, interindividual variability in all five joints is influenced by body side to different extents depending on gait sub-phase and body region, thereby challenging the claim of holistic uniqueness of gait features across all body regions and gait sub-phases. The results therefore underline that previously held assumptions may not hold true, and that their continued use irrespective of innumerable recommendations previously made and in light of novel research, may be detrimental to judicial situations where guilt or innocence is established based on such evidence. Given the findings of this research and paucity regarding empirical basis to support expertise, exerting caution when evaluating gait-based evidence admissibility in the courtroom is highly recommended, since the utility of gait in identification is currently limited.Item Open Access Board Games as a Behavioural Collection Method(Cranfield University, 2020-11-27 12:18) Sidorenko, TatjanaTraditionally, games have been viewed as a form of entertainment. Yet, given how engaging games can be their effects can be beneficial in many domains. This paper explores the use of games as a methodology of exploring the decision-making processes demonstrated by a group of information security specialists when role-playing as malicious actors.To achieve this a board game has been designed which enables players to impersonate different types of attackers each with different motivations and goals. Each player is given a set of tools, techniques and procedures (TTPs) in form of cards and a set of end goals which need to be achieved in order to ‘win’ the game. By interacting with the facilitator, who is also representing the defending organisation or location, they voice out their intended actions and decisions and play a TTP card of their choice. By adopting a persona in an engaging fictional setting players are freed from concerns associated with self-image maintenance and concerns about reputational damage and ultimately, are better able to construct creative and malicious attacks. The game methodology also provides a less limited framework for the data gathering, and with suitable facilitation allows the capture of a very diverse set of attacks.By using this methodology, it is possible to gather a more diverse set of both decision-making behaviour and attacks, improving our understanding of offensive actors. This understanding will then be used to influence the creation of an agent-based simulation of these actors and scenarios.Item Open Access Efficient Space-Time Finite Elements for Thermo-Mechanical Problems(Cranfield University, 2020-11-27 12:47) Quaine, KieranThis talk discusses efficient and reliable Finite Element Methods to simulate the thermo-mechanical response of high explosives. A key motivation is the modelling of the initiation of shear bands in materials such as HMX. The localised plastic deformation associated with a shear band leads to the formation of hot spots and can subsequently lead to thermal runaway. Standard finite element methods struggle to accurately resolve the sharp variations associated with these thermal and mechanical features which may lead to unphysical predictions of the numerical models. The numerical methods presented in this talk aim to provide efficient and reliable tools towards modelling the initiation of shear banding and thermal runaway. We consider two approaches: adaptively generated meshes based on mathematically rigorous estimates of the numerical errors, and enriched finite elements. They are illustrated for thermal and elastic problems, as they arise in reduced models. First, we present results based on adaptive finite elements for non-linear thermal problems. Steep temperature gradients are resolved by appropriate mesh refinement procedures. Steered by indicators for the accuracy of the solution, the algorithm automatically resolves hot spots on a refined mesh, significantly reducing computational costs, see for example [2]. Secondly, we con-sider enriched space-time finite elements (also known as generalised finite elements) which include a priori physical information into the numerical method. This a priori information could represent localised of wave-like features, which are added to a coarse approximation space. The modelling can effectively capture features occurring at different spatial and temporal scales [4, 5]. Here we consider a first order formulation of the wave equation [1] and choose plane-wave enrichments [6]. Future work aims to address the full, coupled thermo-mechanical system, as well as to combine the adaptive and enriched approaches of Iqbal et al. [3].[1] H. Barucq, H. Calandra, J. Diaz, and E. Shishenina. Space-Time Trefftz - Discontinuous Galerkin Approximation for Elasto-Acoustics. (RR-9104), 2017.[2] Heiko Gimperlein and Jakub Stocek. Space–time adaptive finite elements for nonlocal parabolic variational inequalities. Computer Methods in Applied Mechanics and Engineering, 352:137 – 171, 2019.[3] M. Iqbal, D. Stark, H. Gimperlein, M.S. Mohamed, and O. Laghrouche. Local adaptive q-enrichments and generalized finite elements for transient heat diffusion problems. Computer Methods in Applied Mechanics and Engineering, 372:113359, 2020.[4] O. Laghrouche, P. Bettess, E. Perrey-Debain, and J. Trevelyan. Wave interpolation finite elements for Helmholtz problems with jumps in the wave speed. Computer Methods in Applied Mechanics and Engineering, 194(2):367 – 381, 2005.[5] E. Perrey-Debain, J. Trevelyan, and P. Bettess. On wave boundary elements for radiation and scattering problems with piecewise constant impedance. IEEE Transactions on Antennas and Propagation, 53(2):876–879, 2005[6] Steffen Petersen, Charbel Farhat, and Radek Tezaur. A space–time discontinuous galerkin method for the solution of the wave equation in the time domain. International Journal for Numerical Methods in Engineering, 78(3):275–295, 2009Item Open Access Critical Incident Decision-Making: A systematic review of the barriers, processes and frameworks(Cranfield University, 2020-11-27 14:00) May, BrandonCritical incidents are environments that can be characterised by complexity, high-stakes, ambiguity, time-urgency and uncertainty, and often involve a multi-agency response (e.g. Fire and Rescue, Police, and the Military); for example, in terror attacks (e.g. Manchester bombings, London Bridge), fire disasters (e.g. California wildfires, Grenfell Towers), and the 2020 COVID-19 pandemic. In this respect, critical incidents are distinctive, dynamic events in which multi-agency systems lack the situational awareness and operational experience to make effective strategic and tactical decisions. Whilst research has begun to understand and explore decision-making in complex environments, there is limited research that focuses on understanding the processes used to coordinate effective responses in situ within critical incident environments; specifically, critical incident decision-making. This review sought to (i) identify relevant studies, (ii) critically appraise concepts that relate to the central theme of critical incident decision-making in-situ, and (iii) examine the barriers that compound effective strategic and tactical decision-making. The research identified numerous factors that affect the decision-making process (e.g. political agendas, disparity between operational objectives, and intra-and-inter agency collaboration). Additionally, several theoretical and applied decision-making frameworks were identified (e.g. Joint Decision Model; JESIP), that to date, have not factored in how complex, high-stake multi-agency decisions are made under conditions of uncertainty and time-urgency. This presentation will discuss the theoretical implications across security, defence, and law enforcement contexts and present pathways for future research.Item Open Access Dissolution Rates of Chemical Components of an Insensitive High Explosive Formulation(Cranfield University, 2020-11-27 14:14) Gutierrez-Carazo, EncinaThe need of insensitive munition has driven the replacement of traditional explosives by Insensitive High Explosives (IHE), less sensitive to external stimuli. This new generation contains compounds such as 2,4-dinitroanisole (DNAN) and 5-nitro-1,2,4-triazol-3-one (NTO) that have different psyco-chemical properties, making them more labile and mobile through the environment. However, little is known about the persistence and toxicity of these chemicals once released in the environment and this raises the challenge on how they can be assessed for human exposure. Accelerated laboratory experiments such as soil columns or bottle flask have being addressing the problem, although they can be time consuming, expensive and results cannot be extrapolated to different environments. Computational modelling can help to overcome this issue, as it allows the simulation of fate and transport of explosive compounds in the environment under a different insight. Nevertheless, the simulations and predictions made with this approach are not representative enough and they require inputs that can only be obtained experimentally. Additionally, there are extra problems when assessing explosive impact in soil as it is a heterogeneous matrix and it varies over time and studied area. Therefore, the aim of this study is to develop a representative computational model to inform the fate, transport and persistence of IHE compounds in the environment. For that, GoldSim, a simulation software has been chosen due to its flexibly on modelling and due to the possibility of adding stochastic simulations, which are able to better understand and model uncertainties. The model will be used to assess environmental risks of explosives and to help remediation strategies.Item Open Access Assessing the suitability of highly filled energetic composites for additive manufacture(Cranfield University, 2020-11-27 14:40) O'Donnell, MichaelThere is currently significant interest in the development of additive manufacturing (AM) techniques suitable for various energetic materials, such as explosives and propellants. One potential approach in this application space is to use extrusion-based techniques, such as Direct Ink Writing (DIW), to print highly solids filled pastes based upon uncured polymer bonded explosives (PBXs) or composite propellants. In supporting the development of these techniques, it will be important to develop an understanding of how the rheological properties of the materials affect their overall printability, which can be defined as their suitability for a particular AM approach. Such an understanding could enable rapid selection and optimisation of suitable technologies or formulations based upon measurable parameters.This paper reviews the printability of energetic materials in extrusion-based systems, and considers applicable approaches, rheological models and experimental techniques. The design, assembly and testing of custom apparatus for assessing the extrusion properties of an energetic paste are also discussed.Item Open Access Temperature Dependent Toxin Expression in Bacillus Cereus G9241, the Causative Agent of Anthrax like Illness(Cranfield University, 2020-11-27 14:51) Manoharan, ShathvigaBacillus cereus G9241, a member of the Bacillus cereus sensu lato complex, was isolated from a Louisiana welder with a pulmonary anthrax-like illness and is closely related to B. anthracis. Most members of the B. cereus group express PlcR, a pleiotropic transcriptional regulator of secreted toxins and enzymes allowing insect infection, which is activated by the peptide PapR at stationary phase of growth. However, in all B. anthracis isolates, the plcR gene contains a point mutation, which frame-shifts the gene, thus inactivating it. It has been proposed that the acquisition of AtxA, the mammalian responsive transcriptional regulator, was incompatible with the activity of PlcR, leading to selection for PlcR inactivation. Interestingly, G9241 encodes intact copies of both atxA and plcR. Preliminary data has shown that B. cereus G9241 has a temperature dependent haemolytic activity, possibly caused by haemolysins that are regulated by PlcR. We hypothesise that a change in the PlcR-PapR regulatory network in G9241 has allowed the co-existence of plcR and atxA through temperature dependent suppression of the PlcR-PapR circuit at the time AtxA becomes active.Here we investigated whether the activity of the PlcR-PapR circuit and PlcR regulated toxins in B. cereus G9241 are temperature dependent (25 °C and 37 °C), in order to accommodate the activity of AtxA. Plasmid based transcription-translation GFP reporter of PlcR, PapR and PlcR-regulated toxins have been used to study translational activity.Item Open Access Development of a Smart Sniffer Device for the Detection of Illicit Drugs, Homemade Explosives, and their Precursor Chemicals(Cranfield University, 2020-11-30 13:29) Hardy, IonaThe controlled drug market in the UK alone is worth £9.4 billion a year (£19 billion a year cost to society) and is used to finance other crimes, including terrorism with enormous social-economical costs. The threat continues to change and exploitation of the latest scientific and technical advances to enhance operation capabilities for an early detection of terrorist and criminal activities, is at the core of Law Enforcement Agencies (LEAs) operational requirements. Among the detection technologies currently used/explored by UK and International market, a portable sniffer device that can detect multiple illicit substances, in a non-destructive, rapid, and accurate manner, would offer a valid alternative to LEAs.The CRIM-TRACK sniffer device was developed by Cranfield and Danish Technical University (EU FP7 project) and is currently at TRL 4. See attached file for the full abstract.Item Open Access Probing the Structure and Evolution of Anode Materials in Thermal Batteries(Cranfield University, 2020-11-30 13:39) Azad, AtiaHigh-temperature thermal batteries use lithium-silicon alloys as the anode material. Li13Si4, Li7Si3 and Li12Si7 alloys are studied to determine if phase transitions occur or if the alloys become amorphous between room temperature and 500◦C (the typical operating temperature of thermal batteries). These alloys are synthesised by reacting lithium metal and silicon powder at elevated temperature inside an evacuated quartz ampoule. The samples’ structural changes are investigated at elevated temperatures using in situ powder neutron diffraction. This is carried out on the Polaris diffractometer at ISIS facility, Rutherford Appleton Laboratory, UK. The results of the neutron scattering experiment seem to imply that the alloys do not become amorphous at 500◦C and no phases transitions occur in the temperature range. Further work is required to determine if phase transitions occur below room temperature. The work so far has presented a simple method of synthesising these alloys and gives information on the lack of phase transitions between room temperature and 500◦C.Item Open Access Recent Developments from Experiments on HMX Reactions(Cranfield University, 2020-11-30 13:57) Morley, OliviaWhen studying the visible emission of light in the deflagration of energetic materials, two main features are present. Firstly, continuous blackbody radiation across the visible range, which can be used to calculate the temperature of the reaction, by a well-known method using Planck’s formula. Using two different initiation methods of HMX resulted in different temperatures being measured from this radiation, hinting that the reaction pathway is dependent on the initiation insult. The other optical feature that appears are spectral peaks, with light emission at a specific energy/wavelength from particles present in the reacting material. The most intense of these spectral peaks belongs to sodium impurities, which are both prevalent and have a high enough emissivity to dominate over other emissions. Under the high pressures of deflagration, the location of the sodium peak is red-shifted, and found to have a dependence on the pressure (P) and temperature (T). The red-shift was measured under a range of pressures to have a dependence equal to (950 ± 30) PT-0.7 nm, allowing pressure to be measured based on sodium impurity peaks present in the visible emission of deflagration, producing a non-intrusive fast measurement at the point of reaction.Item Open Access Identity Based Consensus for Self-Governing Systems(Cranfield University, 2020-11-30 16:26) Platt, MoritzThe selection of members is a challenge in decentralised record-keeping systems. In ‘permissioned’ systems, this crucial task is performed by a central authority or consortium. In ‘permissionless’ systems, however, the selection process is not trivial and comes with risks. Malicious actors, in a privileged position, can tamper with data, threatening the integrity of the system as a whole. Permissionless membership selection protocols, popularised with the dissemination of distributed ledger technology, have the objective of limiting the influence of a single entity on the wider network.They do so by approximating a participant’s legitimacy, to participate in record maintenance, through external or internal factors. These approximations come with downsides, in terms of attackability, system performance, supported use-cases and resource requirements. In this poster, I propose a prototypical membership selection protocol that uses the measure of personhood as an approximation of legitimacy. Interpreting a decentralised system as a political system, I frame the membership selection problem as one of political representation. I propose a protocol that democratically attributes a personhood score to members, thus creating a self-governing public decentralised system.This work in progress lays out a roadmap for the formal evaluation of self-governing public decentralised systems and describes the anticipated challenges in their implementation.Item Open Access Novel Ceramic Armour for Land Vehicles: Identifying the Chink in our Knowledge(Cranfield University, 2020-11-30 16:58) Powell, DanielVehicle armour is a complex multi-material system, typically comprising of both ceramics and metals. It must meet highly demanding performance criteria; resistance to penetration (often at incredibly high strain rates) must be maximised whilst weight and encumbrance must be minimised. The principles of armour are well-established, although much of the science is under-researched. Some notable knowledge gaps are the adjoining between the ceramic and metal at the interface, the transmission of energy through this interface and how this contributes to armour being defeated. This project aims to further investigate and understand what happens at this interface, ultimately intending to optimise future armour systems. This is to be achieved through computational modelling, initially investigating different combinations of materials and interlayer thicknesses. These models can then be validated against basic ballistic test data, replicating the conditions of the simulations. Once validated, the models can test innovative and non-conventional interlayer geometries, thickness and material combinations, highlighting promising avenues of further research. Whilst still in the infancy of this research, a spreadsheet has been created to allow the visualisation of damaging shock waves through user-defined materials, layer thicknesses and projectile materials. Once validated, it is intended to make this accessible to the wider scientific community.Item Open Access Generative Adversarial Networks for X-Ray Computed Tomography(Cranfield University, 2020-11-30 17:09) Valat, EmilienX-Ray computed tomography is a widely used, non-destructive imaging technique that produces cross-sectional images of bodies sensitive to X-Ray. Inter alia, it relies on exhaustive sampling of the attenuation properties of the scanned material and advanced reconstruction processes. However, acquisition can be toxic for humans or limiting for exotic geometries, as intense X-Ray exposure can lead to cancers during in-vivo diagnosis and experiments chambers have a fixed size that might limit the information gathering process for certain objects. Since sparse data from incomplete scans is yet to be compensated by adequate aftertreatment, we have decided to use deep-learning techniques to extract information on additional modalities to generate missing data in the acquisition.In many routine diagnoses, prior knowledge about the scanned object is often known. Whether it is computer-assisted design drawings or anatomical models, the availability of information regarding the shape of the test sample has led us to look for an acquisition process that minimises object sampling and maximises data harnessing on a known modality. After an introductory period of looking for the suitable architecture and publishing negative results, our exploration of deep generative models has led us to a unique design, one that combines unsupervised feature extraction with graphical models, use of these features for image generation with likelihood-free networks and a constrained optimisation problem to generate high-resolution acquisitions. This model translates our optimal understanding of the problem and an initial analysis suggests the feasibility of our process. Should the concept be promising, many challenges are yet to be addressed: accurate database constitution, efficient training items generation, thorough hyperparameters optimisation and delicate experimentations. As such, these are the next milestones in this investigation. Over the course of the next year, we are determined to deliver a method that is not only novel, but useful to many research fields.Item Open Access Direct Temperature Measurements in Solids via Inelastic X-Ray Scattering Under Shock and Ramp Compression(Cranfield University, 2020-12-01 08:42) Karnbach, OliverShock and quasi-isentropic compression of solid-state matter via laser-ablation affords the creation of high energy density states of matter, with pressures and temperatures of relevance to core conditions within planets in our own solar system and beyond. Crystallographic phase and density can be discerned via ultra-fast x-ray diffraction, whilst pressure is deduced from VISAR measurements. Temperature is more difficult to determine, but techniques based on inelastic scattering from phonons are being considered [1]. It is in this context that we present here multi-million atom molecular dynamics simulations of the phonons present in fcc crystals shocked beyond their elastic limit. Despite high dislocation densities behind the shock front, distinct phonon modes can still easily be discerned, though such defects do contribute to the quasi-elastic peak that will compete with any inelastic scattering signal in a real experiment. Changes in the dispersion curves due to compression and the high number of stacking faults can also be observed.[1] E.E. McBride et al., Rev. Sci. Instrum. 89, 10F104 (2018)For full abstract, see attached file.Item Open Access ASP Triangles: Sketching the Artificial Intelligence of a Mobile Platform(Cranfield University, 2020-12-01 08:49) Di Fraia, MarcoASP triangles are a tool that we introduced to structure the design process of the on-board Artificial Intelligence (AI) of a mobile platform. Their value lies in taking into account the couplings and interactions between macroelements characterizing the platform and the mission context, in analogy to the paradigm shift introduced in aerospace structures by the development of aeroelasticity.