DSDS 19

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Open Access
Absence of Presence
(Cranfield University, 2020-01-10 08:45) Binti zulkifli, Safiah
The tiny the object, the more difficult it is to detect. Failed to detect does not simply signifies the absence of presence. The object may be camouflage and immersed in this huge world - as this image demonstrates! With a booming micro-drones easily available for all walks of life, it is hugely possible for these drones to perform stealthy surveillance being unnoticeable. But, wait! This fact can be avoidable with a specifically design radar for a micro-size target detection. By extracting micro-Doppler signature which is induced by mechanical vibration or rotation from a target – in this case is the flapping wings enable the presence more significant and visible. It is the time to monitor the usage of this presence to avoid illegal and illicit activities for further exploitation. Full control of the latest technology ensure the harmonic and peaceful environment.
Open Access
Adaptations to unaccustomed resistance training for women in physically demanding occupations
(Cranfield University, 2020-01-09 15:41) McGuire, Stephen
Improvements in maximal strength may reduce injury risk and improve occupational performance. Women’s naturally lower muscular strength compared to men, can be offset through resistance training (RT), but research into its implementation has been limited. Therefore, the time-course of muscular adaptations is of interest, with evidence suggesting adaptations in size and strength are detectable as early as 3-4 weeks, concomitant with an attenuation of RT induced muscle damage. This evidence offers a reduction in the time commitment of RT that may enhance readiness for physically demanding activity, but functional adaptations have yet to be explored. The purpose of this thesis is to explore measurement techniques, moderators of baseline variation and responses to unaccustomed heavy-load RT in civilian women representative of individuals entering physically demanding occupations. Specifically, high reliability and acceptable validity as a measure of maximal strength was established for the isometric mid-thigh pull, now a UK Armed Forces entrance test, in non-athlete females. Next, the influence of physical characteristics, previous sporting activity, and single nucleotide polymorphisms on variation in strength was assessed. The ongoing final study aims to assess the efficacy of a 4-week heavy compound RT program on improving performance and biochemical adaptations.
Open Access
Identifying more economical approaches to medical imaging for the rehabilitation of traumatic military injuries
(Cranfield University, 2020-01-10 08:56) Rothwell, Daniel
The cost of National Health Service care for the 265 amputee casualties of British Operations in Afghanistan between 2003 and 2014 is projected to be £288 million (Edwards et al., 2015, Clinical Orthopaedics and Related Research). This cost is due to the development of secondary comorbidities such as osteoporosis, type 2 diabetes, obesity, and cardiovascular disease. An independent and physically active lifestyle can benefit health and prevent such diseases. Physical activity is restricted following lower limb amputation due to a significant loss of muscle and strength. There is also an increased risk of developing musculoskeletal injuries such as osteoarthritis, which is a further barrier to physical activity. In addition, the energy cost of performing activities of daily living is increased, limiting what an individual can do independently. This research aimed to identify economical approaches for using medical images to measure muscle size and support practitioners in tailoring rehabilitation for achieving independently active lifestyles following severe military injuries. The term ‘economical’ was considered with respect to time demand and safety. Imaging modalities considered were Magnetic Resonance Imaging (MRI) and Brightness-mode (B-mode) ultrasound. A large reduction in the time demand of analysing MRI images was achieved by increasing the distance between analysed images. The resulting time demand of 24 hours for the entire lower limb was considered too long for clinical use. B-mode ultrasound was identified as an alternate approach and is valuable for the assessment of those with metallic foreign objects such as shrapnel. A limitation of B-mode ultrasound is the inability to measure individual muscle size although it can measure muscle group size and is useful for physiotherapists and injury rehabilitators. The two methods identified in this research can be used to measure muscle size and monitor changes throughout rehabilitation so that appropriate and timely modifications can be made.
Open Access
Losing Contact with Nano-object
(Cranfield University, 2020-01-10 08:53) Binti zulkifli, Safiah
Micro-UAVs of the size of an insect can be used to perform stealthy surveillance or to gather intelligence crucial to attack roles at a relatively short range and within enclosed spaces and buildings. Conventional radar systems have been optimized to detect and classify bigger targets and are not specifically designed to detect micro-targets of less than 5cm in size. Other micro-targets that are relatively small in size are the insect itself. Insect detection have been a great interest too until now, especially those that can cause damage to the agriculture and wide spread of diseases. Early stage of detection help from further massive destruction to happen. Most entomology radars that are being used now are pulsed wave radars whereas FMCW radar offers a better detection in a closer range target which is less than 150 m to the target. The aim of this research is to develop a radar system to detect insect-like UAVs. Ad-hoc detection will be investigated and developed that can offer improved performance.
Open Access
Group Interaction Modelling of PETN
(Cranfield University, 2019-11-19 15:34) Maisey, Matthew
Group Interaction Modelling (GIM) is a relatively simple model developed to predict the properties of polymers based upon the interaction of a potential function between two adjacent molecules, and a thermodynamic energy balance equation relating the various energy contributions to an ensemble of molecular units. GIM has seen limited application to predicting the properties of explosives, but has not previously been applied to PETN; as result the required GIM parameters to model PETN have not been measured or derived. Here we use single point measurements of a number of PETN properties to fit the GIM parameters, and then validate this fitting process by predicting the temperature dependent response of PETN and comparing these results to experimental data from the literature.Crown copyright.
Open Access
Optimisation of Self-Immolative Systems: Understanding the Role of the Reporter Group
(Cranfield University, 2019-11-19 15:35) Gavriel, Alexander
Stimuli-responsive materials have become significant targets in advance materials as systems of this type offer great potential to perform a variety of functions in a diverse range of applications that span drug delivery (1), biological and chemical sensors (2), diagnostics (3) and degradable polymers (4).Self-immolative (5) systems are comprised of a stable bond between trigger and reporter group, the stability of which is sensitive to particular agents and environments. Recently, we have described (6) the first examples of selective self-immolative systems triggered by a non-acidic electrophilic species to afford a facile colorimetric visual disclosure of toxic electrophilic alkylating agents. Through molecular design, we have carried out a systematic study on the reporter group to explore the balance between stability, reactivity and degradation of the self-immolative system. A structure-property relationship was established from the library of stimuli-responsive molecules synthesised, and an improved detector capable of disclosing electrophiles under ambient conditions realised.References: 1. M. Roth, O. Green, S. Gnaim and D. Shabat, Chemical Reviews, 2015, 116, 1309-1352.2. N. H. Ho, R. Weissleder and C. H. Tung, ChemBioChem, 2007, 8, 560.3. E. Sella and D. Shabat, J. Am. Chem. Soc., 2009, 131, 9934.4. A. Sagi, R. Weinstain, N. Karton and D. Shabat, J. Am. Chem. Soc., 2008, 130, 5434.5. C. A. Blencowe, A. T. Russell, F. Greco, W. Hayes and D. W. Thornthwaite, Polym. Chem., 2011, 2, 773.6. A. L. Acton, F. Leroux, A. Feula, K. Melia, M. R. Sambrook, W. Hayes and A. T. Russell, Chem. Commun., 2019, 55, 5219.
Open Access
Defence and Security Doctoral Symposium Flyer 2019
(Cranfield University, 2019-07-16 17:37) Cranfield University
Flyer promoting the Defence and Security Doctoral Symposium 2019.
Open Access
An End to End Hyperspectral Scene Simulator with Alternate Adjacency Models and Its Comparison with CameoSim
(Cranfield University, 2019-11-19 15:37) Zahidi, Usman
In this research we developed a rendering based End to End Hyperspectral scene simulator CHIMES (Cranfield Hyperspectral Image Modelling and Evaluation System), which generates NADIR images of passively illuminated 3-D outdoor scenes in visible and reflective infrared region i.e.360 nm to 2520 nm. CHIMES is capable of generating 3D geometry based on Digital Elevation Model (DEM) data. The atmospheric data is generated by radiative transfer code, MODTRAN, which is used to generate sky-dome environment map that also includes polarisation effect of sky due to Rayleigh scattering. CHIMES generates materials’ optical radiance by employing Metropolis Light Transport (MLT) method to simulate light. It includes render-time scattering phase function, adjacency-effect, sky-dome emitter and sensor modelling. CHIMES also includes adjacency-effect model similar to commercial Hyperspectral Image (HSI) simulator CameoSim, developed by Lockheed Martin, UK. This similarity is premised by the results of rigorous comparison of both simulators under several atmospheric conditions which shows that both simulators are in agreement when executed under same atmospheric and similar rendering configurations. An improved adjacency-effect model is also incorporated which is again compared with CameoSim. Results manifest that CHIMES together with this adjacency model perform better than CameoSim with respect to ground truth data.Keywords: Hyperspectral Imaging, Synthetic Image Generation, Adjacency-Effect, CameoSim.
Open Access
The temperature effect on the cuticular chemical profile of Lucilia sericata blowfly larvae
(Cranfield University, 2020-01-14 14:47) Kula, Canan
Forensic entomology has become increasingly important in the last decade. In cases of homicide, suicide or suspicious death, insect specimens are taken into consideration as acceptable evidence like blood, fingerprint or any other biological materials. When solving criminal cases, it is essential to determine the time since death or post-mortem interval (PMI). Entomological evidence can provide valuable information about the prediction of the post-mortem interval and where the death occurred.Forensic entomology, like many other fields in forensic sciences, has been developing using new technologies. Cuticular hydrocarbon (CHC) analysis has become a useful tool for identifying and ageing forensically important blowfly species. Variation in hydrocarbon profiles is significant for climatic adaptation, protection against dehydration and desiccation. The effect of other variables, such as environmental climate and geographic region, and how this may change the CHC structure is not known. In the literature, there are some studies showing differences in the hydrocarbon structure of beetles, fruit flies and house flies when reared at different temperatures. Although there are many studies on the relationship between temperature effect and development time of blowfly species using classical entomology methods, no studies have been conducted using cuticular hydrocarbon analysis. In this regard, this study has been a first in the field of forensic entomology. In this study, L. sericata collected from the wild were used for oviposition. Once eggs were laid on the oviposition medium, the Petri dish containing the meat was transferred to incubators at 14 ºC, 25 ºC and 34ºC. The cuticular hydrocarbons were chemically extracted and analysed for post-feeding larvae. The effect of temperature changes on the cuticular structure was investigated by using Gas Chromatography-Mass Spectrometry.
Open Access
Safe Multi-Agent Reinforcement Learning Towards the Engineering of Safe Robotic Teams
(Cranfield University, 2019-11-19 15:36) Riley, Joshua
Multi-agent systems are a collection of agents working in shared environments, often with shared goals while being required to adhere to limited resources. These systems have universal applications and are often deemed as the future of automation in industry; however, an open issue within these systems is ensuring a degree of trustworthiness, allowing human counterparts to be confident that these systems and their individual agents will adhere to expected behaviours even when issues occur. The need for “Safety”, which is often defined in the literature in a post hoc fashion, in these systems can be seen at its most crucial within sensitive operations such as within military application and search and rescue operations. The current state of safety in agents, learning or otherwise, shows much promise with the use of quantitative analysis methods, to deliver a statistical foundation of how likely safety standards will be adhered to. In Multi-agent systems, a large area of literature is dedicated to Petri-net modelling, and using these models to constrict agent behaviour, however, Petri-nets require expertise to design, and analysis of these tools for safety remains an open question. This project aims to look further into the use of the Petri-net tool in modelling multi-agent systems to constrict “unsafe” behaviour while they learn to relatively optimise their behaviours and after this learning has concluded. The project aims to do this by increasing the accessibility of Petri-nets when modelling robot teams, and also further investigate ways to analysis these Petri-net models to deliver a high quality of trustworthiness.
Open Access
Increasing the accessibility of NLP techniques for Defence and Security using a web-based tool
(Cranfield University, 2019-11-19 15:39) Paxton-Fear, Katie
As machine learning becomes more common in defence and security, there is a real risk that the low accessibility of techniques to non-specialists will hinder the process of operationalising the technologies. This poster will present a tool to support a variety of Natural Language Processing (NLP) techniques including the management of corpora – data sets of documents used for NLP tasks, creating and training models, in addition to visualising the output of the models. The aim of this tool is to allow non-specialists to exploit complex NLP techniques to understand the content of large volumes of reports.NLP techniques are the mechanisms by which a machine can process and analyse text written by humans. These methods can used for a range of tasks including categorising documents, translation and summarising text. For many of these tasks the ability to process and analyse large corpora of text is key. With current methods, the ability to manage corpora is rarely considered, instead relying on researchers and practitioners to do this manually in their file system. To train models, researchers use ad-hoc code directly, writing scripts or code and compiling or running them through an interpreter. These approaches can be a challenge when working in multidisciplinary fields, such as defence and security and cyber security. This is even more salient when delivering research where outputs may be operationalised and the accessibility can be a limiting factor in their deployment and use.We present a web interface that uses an asynchronous service-based architecture to enable non-specialists to easily manage multiple large corpora and create and operationalise a variety of different models – at this early stage we have focussed on one NLP technique, that of topic models.This tool-support has been created as part of a project considering the use of NLP to better understand reports of insider threat attacks. These are security incidents where the attacker is a member of staff or another trusted individual. Insider threat attacks are particularly difficult to defend against due to the level of access these individuals gain during the regular course of their employment. The wider use of these techniques would generate greater impact both tactically in defending against these attacks and strategically in developing policy and procedures. There are tools available, however they are often complex and perform a single-task, limiting their use. To generate maximum impact from our research we have developed this web-based software to make the tools more accessible, especially to non-specialist researchers, customers and potential users.
Open Access
Advanced Technologies for the Bonding and De-Bonding of Armour Structures (ArmourBond)
(Cranfield University, 2019-11-19 15:37) Chatzikypraios, Konstantinos
A common multilayer vehicular armour design consists of a combination of adhesively-bonded metallic, ceramic and composite layers. The different properties of each layer contribute in fulfilling the lightweight and the high ballistic property requirements of these structures. Due to their complexity, though, there still are limitations in their performance that are not fully understood. These limitations are associated with a lack in understanding and controlling the propagation of the stress waves, which are induced by the projectile upon the impact event, through the different layers. The stress wave propagation, via reflection and transmission phenomena, is controlled by the acoustic impedance mismatch between the layers. The current epoxide-based armour systems, are incapable of attenuating the stress waves, promoting stress transmission, and exposing the occupants of the vehicles to greatly damaging shocks. Additionally, an increased reflection of the stress waves (in the form of tensile stress) causes the ceramic failure. As a result, the multi-hit performance of the armour is degraded. This PhD study will try to overcome these limitations by focusing on the investigation of novel adhesively-bonded systems, of high energy absorbance capability and improved shock wave attenuation, enhancing the multi-hit capability of the armour. The effect of the material selection and surface treatment on the adhesion and on the mechanical and ballistic performance of the novel structures (using the Split Hopkinson Pressure Bar and the Gas Gun apparatus) will be thoroughly investigated. Further to the above, the controlled debonding of these structures (dismantlable adhesion) will be also investigated, with respect to tailoring the armour against specific threats, fulfilling the “fly light and fight heavy” concept. Finally, the upscaling of the developed materials and structures will take place so that novel armour packs can be tested and validated, according to the STANAG standards.
Open Access
High Resolution Mapping of DCIS Breast Microcalcifications
(Cranfield University, 2019-11-19 15:38) Gosling, Sarah
Breast cancer accounts for 31% of all cancers in women in the UK, making it the most common female cancer. Ductal carcinoma in-situ (DCIS), a malignancy confined to the ducts of the breast, is an increasingly diagnosed cancer which is highly associated with calcium deposits (microcalcifications). Microcalcifications are associated with both benign and malignant conditions and are predominantly composed of hydroxyapatite (calcium phosphate), which has a highly substitutable structure. Therefore, microcalcifications may be important diagnostic indicators of breast malignancy.X-ray diffraction was used, for the first time, to investigate the crystallographic properties of hydroxyapatite in microcalcifications. High-resolution mapping of individual calcifications from a single sample of ductal carcinoma in-situ was carried out to investigate variability of crystallographic parameters within single calcifications, and between calcifications of the same sample. Crystallite size and non-uniform strain are two key crystallographic properties investigated in this study. Numerous parameters showed significant variability both within individual calcifications and between calcifications from the same sample. For most calcifications, values of crystallite size were significantly greater towards the centre of calcifications, however this was not true of all calcifications. This high-resolution approach has revealed potential differential formation mechanisms of calcifications in breast tissue extracted from the same patient. Calcifications may provide an exciting insight into the mechanisms of breast malignancy formation and progression; therefore, crystallographic parameters may have a role as prognostic markers in breast cancer.
Open Access
The realisation of Business Relations Theory; How Did I Get There? A Research Story
(Cranfield University, 2019-11-28 16:16) Alkebaisi, Hussain
This poster aims to visualise the story behind a PhD research, a project through which a management theory was realised. The goal of the researcher is to share his experience in conducting the research, hoping that it will help other colleagues benefit from it.In the poster, the researcher will present a detailed flow chart that shows step by step, how did the researcher initiate his research idea, what barriers were faced during the research, how those barriers were the trigger behind the evolution of the research idea, how was grounded theory research method was applied and led to the research gap and question.The main concern in the poster is that the researcher will explain how a straightforward, simple idea can make a difference if we pay attention to it, and the most important issue is how a researcher can use his own way in conducting research and then to describe ‘How did he Get There’.Keywords – Business Relations Theory, Supply Chain Management, Grounded Theory, Objective-Orientation Approach, PhD Research Story
Open Access
Buying Butter and Guns
(Cranfield University, 2020-01-07 14:35) Oishee, Kundu,
Is defence procurement different from other procurement activities of the government? This poster will present four cases of recent public procurement in the UK and compare the projects from their inception (tendering, selection of supplier) to final delivery in order to find the similarities and differences in military and civilian public procurement projects.It is easy to assume that defence is different or somehow ‘peculiar’ by claiming that the market is uncompetitive or that it is excessively political. However, there are rich literatures in management of major projects, innovation in large technical systems, and the economics of procurement in imperfect markets which suggest the potential for shared learning from seemingly unique projects in order to improve public procurement performance (i.e. to ensure projects are completed on-time and within budget).Methods and dataThe research project uses comparative case study to answer the research question and examines the procurement of the Queen Elizabeth class aircraft carriers, Ajax armoured fighting vehicle and the procurement of high-speed trains for the Thameslink and the Intercity Express Programme. Data is being obtained from government documents and reports (National Audit Office, Parliamentary Select Committees, government departments), Parliamentary debates, newspapers, trade press/industrial magazines, and interviews. The poster will present the data collected in a format that can easily inform the audience about the similarities and differences that can be observed between these four projects along three dimensions:(1) Competition: points related to the market structure, the level of competition between suppliers, and the selection of supplier(2) Challenges: technological, contractual, and political risks encountered in project delivery(3) Management and governance: scope and structure of project teams, training and capacity, turnover, performance review and accountabilityFindings and conclusionThe research uses multi-disciplinary perspectives (economics, management, public policy) for understanding procurement. The findings will be of interest to those interested in military procurement as well as those interested in the potential for cross-learning between the military and non-military sector on the topic of procuring large technical systems.Although data collection is underway and will be completed only by October, comparing the procurement of the Queen Elizabeth class aircraft carriers and rolling stock for the Thameslink programme already reveals important similarities in competition and challenges faced in the procurement of large technical systems by both the Ministry of Defence and the Department for Transport. Case study research is often criticized for not being generalizable but finding similarities in procurement experience for extremely complex projects (as the ones chosen) casts doubt on the assumption that defence procurement is different from civilian public procurement.
Open Access
Automated Question Generation for Delphi Studies
(Cranfield University, 2019-11-19 15:41) Sidorenko, Tatjana
Surveys are a relatively easy and low-cost method for gathering a group opinion on a given subject. Despite there being several survey platforms the adaptation of these platforms for complex Delphi studies still leaves much to be desired. ‘Qualtrics Delphi Toolkit’ (QDT) is a tool that is designed to make the Qualtrics survey platform better adapted for Delphi studies.The Delphi method has been devised to aid forecasting and decision-making. It is a method that gauges the wisdom of crowds to estimate a solution or to come up with an accepted definition. A Delphi study consists of a number of rounds. In the first round, a panel of experts is gathered, each expert shares their opinion on the selected topic. In the second round, the opinions are compiled into a single unified summary that is then presented back to the experts. Each expert is then given an option to alter their original answer for the changes to then be propagated into the summary answer. This procedure is repeated until a consensus is reached. As the use of the Internet has become widespread it has allowed an increase in the magnitude of such studies, through facilitating access to a greater range of experts, as well as enabling the rapid gathering of more information. The tool support, however is often not able to efficiently manage this scale of data collection. Certain functionality, such as the ability to randomly sample a set of questions is not efficiently achievable at the scale required for large Delphi studies. The need for better tool support has become evident after facing the challenge of presenting a list of over 300 hacking techniques to a group of experts. This required stochastically presenting a subset of these techniques maximising expert engagement whilst minimising fatigue and performance decline.QDT is a tool that is written to extend the functionality of a well-known survey platform, Qualtrics, to automatically generate questions relating to a Delphi study. Currently, Qualtrics offers a feature called ‘Piped text’ that passes information from one question to the next. However this feature alone is not enough when there is a requirement to generate large volumes of questions based on previous questions. QDT is designed to automatically create questions from a list of strings. Together with Qualtrics's conditional formatting it allows efficient creation of large volumes of questions where the question text depends on user's previous choice. This will enable the efficient creation of large-scale survey-assisted Delphi studies where the list of topics is very large.
Open Access
Microarchitectural profiling of aging bone with depth
(Cranfield University, 2019-11-19 15:40) Davies, Sammie
Bone is a highly adaptive material and is known to change its structure and composition in times of disuse or overuse [1]. These periods can determine the microarchitecture of bone. This is evident when comparing the skeletal system of those considered “normal” and those coined “tactical athletes” such as military, firefighters and law enforcement [2]. However, occupation is not the only factor that can determine the structure and composition of bone. There are age-related changes that also occur. One example of this is the variability of bone mineral density (BMD) with age. It is known that BMD peaks at 20 years old, plateaus and then declines at 40 years old [3–5]. This reduction is believed to be a result of supressed bone remodelling rates [6]. Alongside BMD, the trabecular structure of bone also changes with age. Trabeculae become thinner or are lost and porosity increases [7–9]. This can lead to a decrease in bone strength [10].This may explain why many skeletal diseases are age correlated, such as osteoporosis (OP) and osteoarthritis (OA). A low BMD alongside the increased porosity seen in OP can lead to increased fragility and risk of fracture [11]. Bone mineralisation is also affected in OA, believed to occur due to overloading and resultant hypomineralisation [12–15]. This overloading is thought to explain why the risk of developing OA is significantly higher in these “tactical athletes” described above [16]. Many studies that have observed the age-related changes to bone considered their samples globally. However, it should be taken into consideration the depth at which these changes occur. Depth related changes propose that there is a factor, extrinsic to the bone, such as loading or abnormal joint tissue, that is determining its structure. By looking at the depth of these changes, this may suggest the extent of this factor’s influence. In the current study, we aimed to offer a microarchitectural depth profile of bone of various ages at a resolution of 2mm. Here, we could investigate the relationship between bone matrix mineralisation, trabecular bone microstructure and aging at differing depths. For this purpose, we determined bone matrix mineralisation (TMD), bone morphometry and bone volume fraction (BV/TV) using micro-CT at different depths in human femoral head cores of varying ages. These cores were harvested from donors from the Melbourne Femur Collection. We aimed to evaluate whether differences in trabecular microstructure could be explained by bone adaptation in age in response to changes in the bone matrix mineralisation and determine the depth to which these changes occur. References:1. Robling AG., Turner CH. Mechanical signaling for bone modeling and remodeling. Critical reviews in eukaryotic gene expression. 2009; 19(4): 319–338. 2. Cameron KL., Driban JB., Svoboda SJ. Osteoarthritis and the Tactical Athlete: A Systematic Review. Journal of Athletic Training. 2016/04/26. National Athletic Trainers Association; November 2016; 51(11): 952–961. Available at: DOI:10.4085/1062-6050-51.5.033. Sheth RD., Wesolowski CA., Jacob JC., Penney S., Hobbs GR., Riggs JE., et al. Effect of carbamazepine and valproate on bone mineral density. The Journal of pediatrics. Elsevier; 1 August 1995; 127(2): 256–262. Available at: DOI:10.1016/s0022-3476(95)70304-74. Hansson T., Roos B. Age changes in the bone mineral of the lumbar spine in normal women. Calcified Tissue International. September 1986; 38(5): 249–251. Available at: DOI:10.1007/BF025566025. Krølner B., Nielsen SP. Bone Mineral Content of the Lumbar Spine in Normal and Osteoporotic Women: Cross-Sectional and Longitudinal Studies. Clinical Science. 1 March 1982; 62(3): 329–336. Available at: DOI:10.1042/cs06203296. Compston JE., McClung MR., Leslie WD. Osteoporosis. The Lancet. 2019; 393(10169): 364–376. Available at: DOI:https://doi.org/10.1016/S0140-6736(18)32112-37. Stauber M., Müller R. Age-related changes in trabecular bone microstructures: global and local morphometry. Osteoporosis International. 2006; 17(4): 616–626. Available at: DOI:10.1007/s00198-005-0025-68. Nagaraja S., Lin ASP., Guldberg RE. Age-related changes in trabecular bone microdamage initiation. Bone. 2007; 40(4): 973–980. Available at: DOI:https://doi.org/10.1016/j.bone.2006.10.0289. Ding M., Hvid I. Quantification of age-related changes in the structure model type and trabecular thickness of human tibial cancellous bone. Bone. 2000; 26(3): 291–295. Available at: DOI:https://doi.org/10.1016/S8756-3282(99)00281-110. Hildebrand T., Laib A., Müller R., Dequeker J., Rüegsegger P. Direct Three-Dimensional Morphometric Analysis of Human Cancellous Bone: Microstructural Data from Spine, Femur, Iliac Crest, and Calcaneus. Journal of Bone and Mineral Research. 1 July 1999; 14(7): 1167–1174. Available at: DOI:10.1359/jbmr.1999.14.7.116711. Consensus development conference: Diagnosis, prophylaxis, and treatment of osteoporosis. The American Journal of Medicine. Elsevier; 1 June 1993; 94(6): 646–650. Available at: DOI:10.1016/0002-9343(93)90218-E12. Donell S. Subchondral bone remodelling in osteoarthritis. EFORT Open Reviews. June 2019; 4(6): 221–229. Available at: DOI:10.1302/2058-5241.4.18010213. Li B., Aspden RM. Mechanical and material properties of the subchondral bone plate from the femoral head of patients with osteoarthritis or osteoporosis. Annals of the Rheumatic Diseases. 1 April 1997; 56(4): 247–254. Available at: DOI:10.1136/ard.56.4.24714. Day JS., Ding M., van der Linden JC., Hvid I., Sumner DR., Weinans H. A decreased subchondral trabecular bone tissue elastic modulus is associated with pre-arthritic cartilage damage. Journal of Orthopaedic Research. September 2001; 19(5): 914–918. Available at: DOI:10.1016/S0736-0266(01)00012-215. van der Linden JC., Day JS., Verhaar JAN., Weinans H. Altered tissue properties induce changes in cancellous bone architecture in aging and diseases. Journal of Biomechanics. March 2004; 37(3): 367–374. Available at: DOI:10.1016/S0021-9290(03)00266-516. Cameron KL., Hsiao MS., Owens BD., Burks R., Svoboda SJ. Incidence of physician-diagnosed osteoarthritis among active duty United States military service members. Arthritis & Rheumatism. John Wiley & Sons, Ltd; 1 October 2011; 63(10): 2974–2982. Available at: DOI:10.1002/art.30498
Open Access
Acoustic Interface States via Material Variation
(Cranfield University, 2020-01-07 15:05) Pearce, Benjamin
Interface states at the boundary between two phononic crystals can arise when the two crystals possess overlapping bandgaps and differing signs in the imaginary components of their impedance [1]. The suitability of a given pair of crystals when designing an interface system can be inferred from the parity of the supported standing edge states marking the beginning and end of their band gap [2]. A crystal that supports a standing wave with an even parity pressure distribution at the beginning of its band gap will possess a differing imaginary impedance sign to a crystal supporting an odd parity state at the start of its band gap [2]. Previous works [1,2,3] have designed such systems by varying the geometry of a crystal, such variations result in the band gap of the crystal closing and re-opening, leading to two crystals with geometries that place them either side of a band gap closure. This will meet the previously given criteria for exhibiting an interface state [3]. The present study uses a variation of materials within a phononic crystal to demonstrate an interface system, whilst maintaining a consistent geometry between the two crystals. FEM Modelling was performed, using the commercial COMSOL software, to show that variations in the material properties of one of the materials within a phononic crystal results in an analogous process of band gap opening and closing. Two, two component 1D phononic crystals consisting of alternating layers of materials ‘A’ and ‘B’ were then designed and modelled to confirm the parity of their band gap edge states. Material ‘A’ was set as 3 mm thick ABS plastic, whilst material ‘B’ was either water or aluminium with thickness of 0.3 mm. The crystals were numerically modelled to provide the transmission spectra both individually and as a combined interface system revealing the predicted presence of an interface state. Initial experimental confirmation is underway, with a preliminary sample of an ABS/water crystal having been constructed, and its transmission spectrum obtained. Results thus far show the presence of the expected modes and a band gap. Further investigations are now underway using an improved sample so that data may be better compared with modelling.References:1. Xiao, M., Zhang, Z. Q., & Chan, C. T. (2014). Surface impedance and bulk band geometric phases in one-dimensional systems. Physical Review X, 4(2), 1–12. 2. Meng, Y., Wu, X., Zhang, R. Y., Li, X., Hu, P., Ge, L., Wen, W. (2018). Designing topological interface states in phononic crystals based on the full phase diagrams. New Journal of Physics, 20(7). 3. Xiao, M., Ma, G., Yang, Z., Sheng, P., Zhang, Z. Q., & Chan, C. T. (2015). Geometric phase and band inversion in periodic acoustic systems. Nature Physics, 11(3), 240–244.
Open Access
What, Who, Where, How: The Impact of Recent Military AI Innovation in Security Terms
(Cranfield University, 2020-01-07 14:46) Ertan, Amy
This poster visualises the results of a narrative evidence review on the topic of military AI innovation, drawing literature from a variety of disciplines to highlight potential unforeseen and/or unintended consequences of ‘Weaponised AI’. There are three main sections outlined to the visual display. The first section illustrates the ‘what’: What does ‘Weaponised AI’ mean and in which applications is the implementation occurring. The second section covers ‘Who and Where’, focusing on state strategy, the role of private industry, and the role additional actors. An empirical example comparing US, Russia and China will be visualised. The third section outlines the ‘How’ of military AI deployment, and leads directly into a discussion section on the implications of current innovation and military processes on categories of security, including strategic and operational aspects.
Open Access
Artificially Intelligent Targeting
(Cranfield University, 2020-01-15 15:24) Westlake, Samuel
The aim of this project is the development of new techniques for infrared anti-ship missile seekers. This image illustrates how we are using deep learning to detect, recognise and classify multiple ships. Our algorithm can differentiate between military and civilian vessels, and is even robust against the presence of infrared countermeasures and background clutter.In most cases, training deep learning algorithms requires thousands, if not millions, of carefully labelled examples. This presents a major challenge for the application of deep learning to infrared missile seekers, as the availability of such training data is extremely limited. To over come this, we simulated multiple thermal signatures for ten different ships and used these to synthetically generate a large and realistic data set. This data was then used to train our artificial neural network, and the subsequent model performed successfully on real-world infrared test data.