DSDS 20
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Browsing DSDS 20 by Type "Poster"
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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.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 Boron Carbide-Silicon Carbide Nanocomposites for Next Generation Armour(Cranfield University, 2020-12-07 13:40) Payne, HenryMotivation for this Work:Modern warfare is developing rapidly; technology is becoming more advanced and the modern soldier requires more of it. With the increase in equipment there is an increase in weight which reduces mobility. Threats have also developed, in such environments greater protection can be required. Combining these two results in a need to produce lighter armour with a higher level of protection. Boron Carbide (B4C) has shown great potential for use in armours. It has a high hardness and low density, but unfortunately it sometimes fails prematurely. This has been explained by a phase transformation involving polytype collapse. This research aims to mitigate structural breakdown by microstructural design. It is hypothesised that a composite containing nano grains of B4C and Silicon Carbide (SiC) can mitigate the polytype breakdown, whilst combining the low density of B4C with the ballistic reliability of SiC.This poster will:• Outline the materials being investigated for use in new ceramic armours. Specifically those under investigation by Imperial College London, joint with DSTL• Give the breakdown of the method and aims of the project• Outline some basic results from initial studies. This will give the reader an idea of the final goal.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 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 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 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 Meteorological Wind Effect on the Ballistic Trajectory of a Medium Calibre System(Cranfield University, 2020-12-02 10:52) Knight, DanielModern systems use a single wind sensor onboard the vehicle to measure and capture meteorological wind data to calculate a weapon systems ballistic offset. The most calculations assumes constant wind between firing point and target for the offset. Meteorological wind is not constant being effect by wind gradient, terrain height and other surface changes. Using trial and test data from multiple wind sensors on a firing range, the wind can be modelled across the full flight of a rounds trajectory. Using modelling and analytical approaches to test known and experimental theories around meteorological wind offset to ballistic trajectory. The modelling provides a cost effective approach alongside practical real data from testing.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 Outsourcing Security and the Reconfiguration of State Power After the Arab Uprisings(Cranfield University, 2020-12-02 10:41) Moussa, EngyThis research explores how increased privatization and outsourcing of security in some Arab countries since the 2010-2011 uprisings has contributed to the reconfiguration of state power and the survival of authoritarian rule. This enquiry is pursued in two case studies: Egypt and Tunisia. The considerable historical and contemporary similarities between both countries offer rich grounds for comparative analysis while the particularities of each case present unique elements of analysis and grounds to draw different conclusions to test in other cases.While acknowledging the neo-liberal roots of the current expansion of the private security industry in the Arab region, this research argues that this development essentially fits into an ongoing framework of authoritarian adaptation pursued by the Arab region’s ruling regimes to ensure their survival and prosperity. This manifests through the provision of alternative agents and strategies for social control alongside new venues to expand regime interests.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 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.