PhD, EngD, MPhil and MSc by research theses (CDS)

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Open Access
The Armed Forces of Australia, Britain and Canada and the impact of culture on joint, combined and multi-national operations : a methodology for profiling national and organisational cultural values and assessing their influence in the international workplace
(Cranfield University, 2004-01) Stocker, Ashley; Taylor, Prof T.
This study identifies the influence of national and military organisational values on the cultures of the armed forces of Australia, Britain and Canada, in order to assess the impact of culture on Joint, Combined and Multinational operations. This is achieved by: · Defining culture, values and related concepts. · Outlining a viable methodology to examine and profile cultural values. · Demonstrating why values form the basis of this study. · Reviewing the body of cross-cultural academic literature on cultural values and the military. · Executing a measurement of values in a consistent and academically sound manner. · Examining national influences on the culture of the armed forces of Australia, Britain and Canada. · Examining intra- national organisational influences on the culture of the services of the armed forces of Australia, Britain and Canada. · Examining international organisational influences on the culture of the services of the armed forces of Australia, Britain and Canada. · Focusing on the values of the armed forces examined in this study in order to compare the findings with the results obtained from the Values Survey Module. · Discussing the implications of the findings of this study and demonstrate how the values of the nations and organisations that have been examined can be expected to affect future operations.
Open Access
Armoured vehicle manufacturing in the Gulf States challenges and future vision: a systems engineering perspective
(Cranfield University, 2019) Aljeeran, Isa Khalifa Abdulla; Hameed, Amer; McCormack, John; Adcock, Rick
The armoured vehicles manufacturers (AVMs) in the Gulf States encounter many difficulties related to their current performance, their customers' circumstances and the interactions between them. The AVMs are Small and Medium Enterprises (SME), owned by entrepreneurs who manage their organisations intuitively, leading to likely performance degradation which affects their outputs and thus customer satisfaction. On the other side, the customers lack essential elements of the acquisition process such as the non-existence of published defence strategies documents, customer needs not being precisely clarified to the developers, demand fluctuation, customer individuals’ knowledge being insufficient to contribute toward developing the intended values, etc. Third, the interactions between AVMs and their stakeholders, the customer in particulars, do not rise to the level of product importance. These environments form the dynamic environment that AVMs in the Gulf states currently face besides other circumstances, such as the fierce competition worldwide, considerably changes regarding the threats and needs, constant technology advancements, and political challenges, which combined may hinder AVMs from attaining their instant (customer satisfaction) and future (market sustainability) goals. Therefore, this thesis pursues aims to enable the owners/managers (entrepreneurs) of AVMs in the Arabian Gulf States to employ their resources efficiently to deliver innovative values that satisfy the needs of all of their stakeholders, customers in particular, within the dynamic environment. Dealing with the dynamic environment requires intensive planning and the execution of known managerial disciplines, such as strategy, supply chain and business to business (B2B) interactions along with utilising essential tools provided by the System Engineering (SE) discipline. The latter subject has adequate means to optimise the strategy and supply chain technical tools by integrating them with the related managerial tools to enhance the development efforts. Moreover, organised interactions among various related entities that share a well-designed network enforce the desirable integration and enhance the relationship in the B2B context which ensures customer satisfaction, confirms the AVM market’s sustainment, strengthens the defence industry and attains arms independence. These efforts must be monitored and controlled by higher national authorities’ substantial strategies to ensure that the national goals are achieved. Therefore, the author suggests a conceptual model to guide all interested parties, the AVM’s management, to enhance their performance by considering all essential managerial and technical aspects. The model also emphasises the importance of interactions in enforcing the applications of the strategic, design, production and test and evaluation process to enable AVMs to enhance their product development in order to capture customer satisfaction and succeed in business. The success of the national AVMs will lead to the attainment of one of the most important national objectives, i.e. arms independence.
Open Access
Bistatic SAR for Building Wall Material Characterisation
(Cranfield University, 2020-07) Elgy, James; Andre, Daniel
This thesis addresses the problem of using radar to extract interpretable information concerning both the structure and electrical properties of a wall, and the environment behind it. This is broken down into two subproblems: how to determine the thickness and electromagnetic properties of the wall without being in direct contact with it, and how to obtain the most accurate images of what lies beyond the wall. Existing research in the area is evaluated and a theoretical study is presented on the use of monostatic, bistatic, and multistatic Synthetic Aperture Radar (SAR) in both one and two dimensional apertures. New methods of determining the wall properties are evaluated by both computer simulation and with laboratory radar measurements, where a wall of concrete blocks is constructed. The robustness of the asymmetric SAR geometry approach is evaluated with the addition of complex objects placed behind the wall. The uncertainty associated with estimating the wall properties is evaluated and consequential improvements to image quality are discussed. It was found that an asymmetric bistatic SAR geometry accurately extracts the refractive index and thickness of a wall. The method is applicable to both cluttered environments and non-parallel wall trajectories without loss of accuracy. Applying a compensation for refraction in the SAR imagery results in better positional accuracy but does not necessarily result in better image focusing. Volumetric multistatic image formation benefits from applied refraction compensation. SAR image formation, and in particular volumetric image formation, can be significantly accelerated via a spatially variant basebanding technique followed by zero padding. Spatially variant basebanding is sub optimal when applied to a Through-Wall radar scenario where there is a visible wall signature in the image. Keywords: Through-Wall radar, Multistatic radar, Multidimensional signal processing, Electromagnetic propagation, Radar imagin
Open Access
Calorimetric Investigations of a Series of Energetic Polyphosphazenes
(Cranfield University, 2008-10-07T12:47:49Z) Contini, Alessandro E.; Bellamy, A. J.
Energetic, fluorinated, linear polyphosphazenes are currently under investigation as potential, high-density binders for new, polymer bonded explosive compositions. A series of such polymers was synthesised and the enthalpy of combustion of each member of the series was measured by static bomb calorimetry. This was performed after combusting appropriate secondary thermochemical standards to model the combustion stoichiometry of the heteroatoms nitrogen, fluorine and phosphorus. The water-soluble combustion products were identified and quantified using 19F NMR spectroscopy and Ion Chromatography. Since some of the combustion products are hydrolytically unstable, it was found necessary to stabilise the initial combustion product mixtures by using a buffer solution instead of pure water in the bomb, and then to determine the composition of the stabilised product mixtures in order to obtain meaningful values for the enthalpies of combustion and thence enthalpies of formation. The thermochemical measurements themselves were made with pure water in the bomb. The composition and structures of the various polyphosphazenes were correlated with their energies of combustion and enthalpies of formation. The latter were calculated using the latest CODATA values of enthalpy of formation of the combustion products. The ‘combustion’ of the polyphosphazenes under a nitrogen atmosphere was also investigated with the view to calculating the enthalpies of detonation of each member of the series. Three conference papers which include the results of this work have been published and are included in Appendices C-E.
Open Access
The characterisation and provenancing of ancient ochres
(Cranfield University, 2010-04) Attard Montalto, Nicola; Rogers, Keith; Shortland, Andrew J.
Open Access
Culture Management through the balanced scorecard : a case study
(Cranfield University, 2007-12-12T14:08:54Z) Woodley, P M; Jackson, S; Robertson, J
Neuro Linguistic Programming argues that repeating previous behaviour will only succeed in delivering previous outcomes. Kaplan and Norton’s Balanced Scorecard is about getting different results. For successful change, managing complex and higher functions such as managing motivation and the beliefs of staff members must take their place alongside environmental and capability issues such as physical equipments. Mechanistic processes such as the Balanced Scorecard can nevertheless be used to manage softer aspects of change such as culture, as part of an integrated holistic management system. This needs to be done through adoption of key Balanced Scorecard processes. A principal feature of the Balanced Scorecard which can be applied here is the development of a cause-and-effect model of cultural issues with clear and measurable linkages to organisational performance. The degree to which national or organisation culture supports or conflicts with these processes needs to be considered. However, the Balanced Scorecard must be implemented properly in order to be effective in managing the organisation. This research examines the Balanced Scorecard implementation in one organisation and examines the inter-relationship with associated cultural issues. Criteria are defined for managing and assessing Balanced Scorecard implementations. From the main case study a model for understanding the importance of organisational culture is developed. A cultural measurement tool is then developed and tested within this organisation to show how the cultural measurement can be integrated into the Balanced Scorecard regime. Effective measurement is an essential precursor to effective culture management. The results of cultural measurement are used to explore potential management issues. The strands of work are merged in a final set of case studies that use the developed models to assess Balanced Scorecard implementations in other organisations. These case studies illustrate how cultural issues have affected Balanced Scorecard development.
Open Access
Determination of Residual Stress Distributions in Autofrettaged Thick Cylinders
(Cranfield University, 2008-10-07T12:21:57Z) Gibson, Michael C.; Hameed, Amer
High pressure vessels such as gun barrels are autofrettaged in order to increase their operating pressure and fatigue life. Autofrettage causes plastic expansion of the inner section of the cylinder – setting up residual compressive stresses at the bore after relaxation. Subsequent application of pressure has to overcome these compressive stresses before tensile stresses can be developed, thereby increasing its fatigue lifetime and safe working pressure. A series of Finite Element (FE) models of hydraulic autofrettage were created, to establish the correct boundary conditions required and means of developing accurate but computationally efficient models. Close agreement was observed between the solutions obtained from the developed models and those from existing analytical and numerical models. These initial models used a simplistic bi- linear stress-strain material representation; this deficiency was then addressed through the development of two means of creating radial position dependent non-linear material behaviour within FE, crucial for accurate prediction of residual stresses. The first utilised a method of altering the elastic properties of the material to achieve nonlinear stress-strain response. This provided accurate results that compared well with existing methods, but was unable to be used in simulation of swage autofrettage due to its elastic nature. The second method achieved non- linear behaviour through direct manipulation of the stress and plastic strain states of the FE model at a fundamental level. This was hence suitable for arbitrary loading procedures, including swage autofrettage. A swage-like model that applied deformation via a band of pressure was developed, to investigate the influence of localised loading and shear stresses that result on the residual stress field. A full model of swage autofrettage was then developed, which was optimised on the basis of accuracy and solution effort. It was then used to investigate the effects of various mandrel and contact parameters on the creation of residual stresses. The model is suitable for use in future optimisation studies of the swage autofrettage procedure.
Open Access
Development of an analytical framework to assess the risks posed to soil by emerging contaminants and chemicals of military concern.
(Cranfield University, 2022-11) Persico, Federica; Temple, Tracey J.; Coulon, Frederic
Soil provides multiple essential functions, such as provision of food and raw materials, a platform for urban development and human wellbeing and as a filtering and transforming medium. Many unregulated contaminants, often termed emerging contaminants, are globally released on soil creating potential risks, especially when undetected leading to significant impact on environmental receptors. The UK ministry of Defence plays an important role in soil protection as the biggest holder of Sites of Special Scientific Interest (SSSI) in the UK as well as being an active polluter in these protected areas through essential training activities. Therefore, there is a need to improve methods for early identification of emerging contamination to avoid long term environmental impacts and costly remediation. The research undertaken for this thesis has contributed to the development of a soil analytical framework to facilitate early identification of the deleterious effects of emerging contaminants and chemicals of military concern on soil. During this research two different scenarios were considered, firstly, when there is a significant body of ecotoxicological data available for a specific contaminant in the literature and secondly, when ecotoxicological data is not available. A scale based on potential hazards was created for the first scenario, which aims to classify chemicals into three categories - low, medium, and high environmental hazards. This scale serves as an inexpensive method to identify the risk of soil degradation. Results from this research showed that for the contaminants of interest (e.g. 1,3,5-trinitro-1,3,5-triazine - RDX, 2,4,6-Trinitrotoluene - TNT, Perfluorooctanoic Acid - PFOA, Perfluorooctane Sulfonate - PFOS and Cypermethrin) the low-level hazard values were lower than expected. These values were expected to correspond to existing Soil Screening Values (SSVs) and Ecological Soil Screening Levels (Eco-SSL), meaning that the contaminants are likely to have a negative impact on the soil at lower concentrations. For the second case, when data is not available experiments need to be undertaken to generate primary data. Insensitive High Explosives (IHE) compositions were identified as lacking data and explosive residues were collected and soil mesocosms were carried out to define the long-term consequences on soil. Field experiments were used to quantify IHE residue deposition concentrations from a standard 155 mm artillery shell, which was then used to estimate potential contamination after 100 detonations. These values were used to estimate low, medium and high contaminant concentration for soil mesocosm studies to quantify the impact on soil using indicators identified through literature review. A standardised procedure was developed based on this, which quantifies the consequences of explosives on soil. This procedure revealed that soils that are already degraded are more susceptible to the impact of explosives, which primarily affects the chemical and biological properties of the soil. . Specifically, this work has shown that the frequent use of IHE filled munitions on training ranges will have an effect on the quality of the soil even when low quantities of energetic residue are deposited. Results for this thesis represent a first step towards a more comprehensive soil analytical framework development providing early identification tools for soil protection.
Open Access
The effect of ionising radiation on the explosives: TATB, HMX and PETN
(Cranfield University, 2019) Lewis, D. A.; Akhavan, Jacqueline; Cook, M.; Wilson, I; Stennett, C.
The effect ionizing radiation, specifically gamma, has on three of the most well known explosive materials; HMX, PETN and TATB, has been studied experimentally and computationally. Samples of these explosives that had been irradiated in vacuum to a total dose (equivalent to water) of 200 kGy by an average incident energy of 1.25 MeV, showed changes to their explosive and physical properties to varying degrees, with sensitivity to impact being most notably changed for PETN and HMX. Changes to the thermal properties of HMX and TATB, alongside the detection of long lived radicals for TATB and PETN, suggests alterations to each material’s chemistry. Changes were only detectable in solid state analytical methods, indicating that alterations to these materials are isolated within this state. Through comparison with other data, these changes appear to be highly dependant on the gaseous environment in which they are irradiated, with vacuum having the most significant effect. The widely reported greening of TATB under the influence of gamma (and ultraviolet and x-Ray) irradiation was found to be reversible upon re-crystallisation, with the process also appearing to remove the long lived radical that had existed in the material for over eight years. Radical concentration appears to correlate with total absorbed dose along with the level of green within the material. Computational investigation attributes the discolouration of TATB to the cationic radical derivative of TATB, which is stabilised by de-localised pi-bonding resonance of the constitutive aromatic ring, it is also suggested that this is the source of the radical signal observed in ESR analysis.Further computational investigation suggests that purported decomposition products of TATB such as the mono-furazan, mono-nitroso and phenoxyl radical are not the source of the discolouration and are also not thermodynamically favourable, unless the monofurazan or phenoxyl derivatives are in a cationic form. Thermodynamic evaluation of potential decomposition pathways for PETN and HMX yield a selection of energetically favourable products, however the significant majority are, like TATB, in the cationic radical form. Simulated ESR spectra for purported HMX decomposition products did not agree with those observed in literature, attributed to their short lived nature. However a measured long lived radical in TATB is attributed to the cationic radical form of TATB, the purported source of the discolouration. A long lived radical in PETN was also measured and assigned to the cation derivative of PETN by comparison with computational predictions.
Open Access
Effect of wind turbulence on wind ballistic trajectory of a medium calibre weapon system
(Cranfield University, 2023-10) Knight, Daniel; Simner, Dave; Goyder, Hugh; Helliker, Aimee
Current ballistics and Fire Control Systems (FCS) use the assumption that crosswind located at the firing point will be constant between firing point and target location. The single constant crosswind value is then used to calculate the ballistic drift offset required to correctly engage a target at range and maintain an accurate firing solution. Variations in crosswind speed and direction are not considered by FCS but are known to cause drift errors in flight and offset the resulting impact point, the error is commonly known as gustiness. Applying a variable crosswind drift correction for both time of flight and projectile height could produce an improved result by considering variations in the crosswind dynamics. Using multiple crosswind sensors at difference heights, a wind gradient curve can be produced to model wind turbulence and speed variations in reference to the projectile trajectory height. Similarly, changes in the crosswind can be modelling against the engagement timeline to show gustiness in relation to the time of flight of the projectile. The accuracy and performance of the new ballistic model can be measured against the NATO standard coincidence window, which is used to evaluate FCS accuracy. The NATO error window of 0.3 mrads can be used to measure the probability of hit between the current constant crosswind and the new variable crosswind FCS model (US Army Aberdeen Test Center, 2009b). Using a reference tank target at a nominal distance of 2,000 meters, gives a coincidence window requirement of 60 cm square located on target centre mass. The thesis found for the reference projectile used, a 40CTAS 40 mm round (CTA International, 2018b), that the FCS accuracy could be improved by 10.95% when including variations in the crosswind. The probability of hit inside the NATO coincidence window is improved to 56.16% when using crosswind at the instant of firing, compared to holding a single constant value during the engagement timeline. It was also found that dynamic crosswind conditions can be included and modelled into a Point Mass Ballistic Model. Variations in the crosswind gradient curve can be used to assess turbulence and change in wind conditions. The wind gradient curve also demonstrates that wind conditions are not constant in relation to both time and height above ground, during an engagement sequence.
Open Access
The effects of 3D printed material properties on shaped charge liner performance
(Cranfield University, 2019) Agu, Henry; Hameed, Amer; Appleby-Thomas, Gareth J.
Shaped charges operate by explosively loading a (typically metallic) liner to produce a jet travelling at extremely high velocity (9-12 km/s). Such explosive loading involves highly non-linear transient phenomena. As such, a very wide range of physical processes must be considered to enable accurate characterisation of such events – with material behaviour within these (pressure / strain-rate) regimes providing insight into problems ranging from shaped charge performance itself through to formation of new material phases at high pressures. Unlike other high strain impact events, the shaped charge phenomenon results in hydrodynamic material flow of the liner which is an integral aspect of the shaped charge design. As such, the study of shaped charge liners has been the subject of numerous scientific research studies for over 50 years since its discovery. When explosively loaded, the liner is stretched extensively during their elongation to form a jet. The jet length depends on the ductility of the liner material, and this is strongly linked to the microscopic crystal structure, which depends on the original material properties and the processes used to produce the liners. There are several processes currently used for liner production. This thesis outlines the different liner production techniques, their advantages/disadvantages and explores the potential of employing additive manufacturing (3D printing) technique for shaped charge liner production. As 3D printed parts are being considered as a possible replacement for conventionally processed parts, this PhD work fits into this long-term vision; with built parts compared in density and mechanical strength to their bulk material equivalents. More so, 3D printing is shown to present some potential benefits for the production of efficient liners including high precision, cost-effectiveness and the potential to realise customized geometries. The use of fine powders may also allow alternative microstructures to be produced with potentially interesting results. This element of the study forms the first part of this thesis, aimed at investigating the mechanism elucidating the performance of 3D printed liners processed through direct metal laser sintering process (selective laser sintering) and filament deposition modelling processes (Polylactic Acid). The next part of this work provided additional insights on the additive manufactured processed employed through investigation of the dynamic behaviour of polylactic acid, employed in the filament deposition modelling process and static (optical and scanning micrographs) observation of the laser sintered liners in their as - manufactured and deformed state, in comparison with traditional machined liners. Autodyn 2D numerical hydrocode was employed to understand how temperature influences the deformation pattern (grain refinement); providing new insights on liner deformation. Finally, a novel computational technique to determine the Virtual Origin of shaped charges was developed to provide a ready route to predict more accurate SC performance.
Open Access
Effects of Particulate Contamination and Jet Fuel Chemistry on the Nucleation of Water and Ice in Aircraft Fuel Systems
(Cranfield University, 2022-04) Ugbeh-Johnson, Judith; Carpenter, Mark; Mai, Nathalie; Williams, Mike
The aviation industry is currently facing increasing environmental and energy challenges regarding its fuel use. Research is therefore currently under way to develop new sustainable aviation fuels. Understanding the properties of these fuels (along with the changing properties of existing fuel types) is required to understand their impact on aircraft fuel systems. Water solubility, water settling and ice formation in fuel are such properties of interest. The presence of water in jet fuel/fuel systems has been a long-standing issue in the aviation industry. Therefore, it is important to precisely identify the conditions and features that may exacerbate this phenomenon, understanding how fuel composition, temperature, water droplet sizes, flowrate and pipe surface affect ice formation and water solubility. Currently, there is relatively limited data regarding water solubility/settling rate and ice formation in sustainable fuels, specifically those specified in ASTM D7566. This work gives a comprehensive account of the recent advances and technologies in the literature indicating conditions that might lead to the nucleation of water and ice in aircraft fuel systems. These conditions have then been applied to characterizing dispersed water droplets in alternative fuels and conventional Jet A-1. Subsequently, the requirements have been applied to the design, set up, and effectiveness of an ice test rig to understand the types and amounts of ice that can be produced from different sustainable aviation fuel blends. In doing so, this work has helped shed light on the role of fuel composition in ice accretion and whether ice accumulation on a pump inlet strainer may impact pump performance. Furthermore, the results from this work will serve as a basis for design guidelines to minimise ice formation within an aircraft fuel system and help identify some potential/sustainable jet fuel candidates for ASTM D7566 certified jet fuels.
Open Access
Enhanced radiopacity austenitic stainless steel foil
(Cranfield University, 2007-12-12T15:52:58Z) Craig, C. H.; Friend, Clifford M.; Edwards, M. R.
Austenitic stainless steel designed for implant applications is used to fabricate balloon expandable coronary stents. The alloy was not designed for this purpose but has been found to work well except for relatively low radiopacity in the energy range used for stent deployment, typically 80kV to 100kV. Stents made of more dense elements such as tantalum exhibit high radiopacity in this energy range. Low radiopacity is due to a combination of tubular stents having a thin wall (strut) thickness (less than 0.13mm) and the alloy being comprised of low-density elements, approximately 2/3 iron and 1/3 chromium and nickel. To retain the desired thickness and increase radiopacity, alloy density may be increased by partial substitution with dense element(s). The new alloy must maintain the biocompatibility, corrosion resistance, non-ferromagnetic structure, strength, ductility, and fatigue- and fracture-resistant characteristics that made the original alloy attractive to stent designers. Coronary stents are subject to intensive review by regulatory authorities prior to being approved for human use, thus stent designers are hesitant to depart from accepted standards in selecting new alloys. Revising an existing alloy is the preferred approach to achieve subtle feature changes. A set of criteria was set that maintained chromium, nickel, and molybdenum within prescribed compositional ranges and diminished iron to its minimum level, allowing platinum to be substituted for approximately 1/3 the total elemental weight (wt%). Above 20wt% platinum, undesirable precipitates were found. An alloy containing 20wt% platinum, in the form of foil and at a thickness of 0.127mm, was found to be free of precipitates not found in the base or original alloy and to provide approximately 20% radiopacity increase at 80kV and 15% radiopacity increase at 100kV, exceeding minimum programme goals at 80kV and equaling those at 100kV.
Open Access
Evaluating the Effectiveness of Offsets as a Mechanism for Promoting Malaysian Defence Industrial and Technological Development
(Cranfield University, 2008-04-17T10:25:11Z) Balakrishnan, K; Matthews, Ron
Offsets have taken centre stage in defence trade. To date, more than 78 countries around the world practice offsets and outstanding offsets obligations run into billions of US dollars However, why have offsets gained such a momentum? Increasingly, both sellers and buyers in the arms trade view offsets as an efficient and effective economic compensation tool to justify arms deals. Buyers, consider offsets as a catalyst for industrial and technological development, employment, creation of value-added activities and skills development. Sellers, on the other hand, perceive offsets as providing product differentiation and competitive advantage in an already tough defence market. The question, though is whether, do offsets really work as claimed? The purpose of this dissertation is to empirically verify the above proposition by evaluating the effectiveness of defence offsets in developing a defence industrial and technological base, using Malaysia’s defence industry as a case study. This study employs a Multi-Method or Triangulation Methodological approach (comprising survey, archival sources and participatory observation) to gather data. Fieldwork research employing questionnaires and interviews were undertaken as part of a survey of Malaysian defence companies, international defence contractors and relevant offsets-related government and non-governmental agencies. These data were further substantiated and consolidated via archival sources, such as government and company reports and also participatory observation. Research analysis indicates that offsets have provided mixed results, in the case of Malaysia. The successes have been mainly focused on technology capability-building and human resource development, limited to through-life-support of the defence equipment and the ancillary systems purchased. Morover, offsets have been successfully used to diversify into civil sectors, mainly aerospace and electronics sectors, leading to increased exports, jobs, backward linkages and technology enhancement in these sectors. However, offsets have had minimal effect on creating joint-production, collaborative activities and R&D programmes, requisites for the process of Malaysianisation. Further, offsets have also been less than effective in increasing employment, and dual-use technology programmes that could provide longterm impact on Malaysia’s economic growth. Overall, Malaysia’s offsets policy has been pragmatic and flexible. The government has played a vital role in ensuring that the offsets policy operates in tandem with Malaysia’s national aspirations. Yet, offsets have had a limited impact on developing and sustaining Malaysia’s defence industrial and technology base. The offsets policy aim and objectives have not been clearly reflected in the offsets process and implementation. As defence offsets will continue to be of an essence in Malaysia’s defence procurement activity, initiatives should be taken to review the offsets policy and implementation processes. The review should augment the effectiveness of offsets in developing measurable and value-added programmes that build a sustainable and competitive Malaysian defence industry. To this end, and based on the research findings of this study, a number of important policy recommendations are advanced to raise the effectiveness of Malaysia’s offsets policy.
Open Access
An evaluation of small satellite technology transfer and capability-building in Algeria
(Cranfield University, 2018) Ayad, A; Matthews, Ron
The potential for satellite technology to make an essential contribution to socio-economic development has been recognised by the international community since the onset of space adventure in the late 1950s. Due to its complexity and the resources required, satellite technology development has always been the reserve of major powers. However, a new trend emerged in the 1990s towards developing smaller and cheaper satellites. It is driven by the spectacular development in information and communication technologies, advances in technology miniaturisation, rising performance of off-the-shelf components, and space sector globalisation. This trend has lowered barriers to entry for small developing countries. They have used the new mechanism of small satellite collaborative projects in order to transfer Earth observation small satellite technology from developed countries. Like other developing countries, Algeria has leveraged this trend and engaged successively in three Earth observation small satellite collaborative projects with foreign companies in order to build small satellite capability. The purpose of this study is, thus, to evaluate whether Algeria has skilfully combined the technology acquired from abroad with local efforts to build effective and sustainable local small satellite capability. Technological capability-building through technology transfer usually refers to the ability to reconcile two categories of factors: i) exogenous factors, external to the country’s socio-economic environment, that condition the transfer of technology from abroad - these factors are traditionally gathered under the body of knowledge called ‘technology transfer’; and ii) endogenous factors, relating to the local effort to effectively acquire and indigenise the transferred technology – these factors are traditionally gathered under the body of knowledge called ‘technological capability-building’. Technological capability-building through technology transfer is also viewed as a learning process where knowledge is transferred from abroad and locally diffused. The evaluation approach adopted in this study examines the small satellite capability-building programme from a knowledge-oriented perspective. Algeria’s ii context is appraised by using the Innovation System analytical approach. The programme planning is evaluated by using the ‘strategic planning’ analytical approach. The programme implementation is evaluated by placing technological learning at the heart of the study. Two systemic models for the evaluation of knowledge flow from the transferor to the transferee, and then to its local environment, have been devised and tested. The knowledge-oriented perspective has been triangulated with perspectives stemming from the two traditional bodies of knowledge: technology transfer and technological capability-building. The evaluation has been comprehensive by taking into account factors across different levels of analysis: individual and team (micro level); organisation or firm (meso level); and national, sectoral and international (macro level). The evaluation has been performed through a mixed method research design. The research findings indicate that the process of building small satellite technological capability in Algeria has provided mixed results, and the most concerning are at the macro level. Algeria has failed to establish a strong foothold between the nascent satellite development activities and a local supply chain. Moreover, at the meso level, Algeria has not established an effective learning organisation that can lead, synergistically and coherently, satellite development activities. Finally, at the micro level, Algeria has failed to align technology transfer mechanisms with satellite development objectives. Based on these findings, the study highlights the need for clear strategies with prioritised objectives. It recommends elevating management capability-building as an absolute priority, and suggests the adoption of appropriate technology transfer mechanisms and a diversified projects portfolio.
Open Access
From capability to concept: Fusion of systems analysis techniques for derivation of future
(Cranfield University, 2007-03-27T09:11:22Z) Sparks, Emma S.; Couldrick, C. A.; Iremonger, M. J.; Allsop, Derek F.
The intent of this thesis is to define a set of processes for use within UK Government dismounted soldier systems research that will provide stakeholders with auditable and traceable information to understand gaps in military capability and justify future procurement decisions. The need for this approach is linked to organisational shifts within the UK Ministry of Defence, and more specifically Government research with the move towards procurement of capability rather than equipment. In conjunction with reducing defence budgets and increased scrutiny, there is a need to prioritise spending to those areas that will provide the most significant enhancement to operational effectiveness. The proposed process suite provides underpinning data to support Government decisions, from definition of military need through to concept design and prioritisation of future research activities. The approach is grounded in the field of systems thinking and systems engineering providing the logical and systematic constructs required for highly complex systems where the human is a central focus. A novel fusion of existing systems tools and techniques enables both subjective data from domain experts and objective data in the form of operational analysis and field trials to be utilised for analysis across the five NATO capability domains, with output defining the relative importance of survivability, sustainability, mobility, lethality and C4I in the context of operational and strategic level military goals as well as wider challenges represented by the doctrinal defence lines of development. Future developments should include alignment with developing pan-MoD initiatives in the form of MODAF, if required by the customer organisation. This would enable generic versions of the process suite to be applied to any defence domain and problem.
Open Access
Health and usage monitoring system for military vehicles
(Cranfield University, 2019) Al Abri, M. S.; Hameed, Amer; Thirulogasingam, Thiru; Khanal, Bidur
The aircraft industry has been able to adopt improved maintenance and logistics planning as a result of the technological advances in Integrated Modular Avionics (IMA) and Equipment Health Monitoring (EHM). Same cannot be said about the land system. In the land environment, military vehicles are well behind in achieving the same abilities and hence, the problem of inefficiency in the maintenance and logistics for land based system needs to be addressed. To address this and assess the viability of integrating HUMS and Autonomic Logistics on military land vehicles, this project was proposed. Three main contributions from this research which adds to the knowledge are: (1) assessment of some real system failure which could lead to a poor operational readiness, (2) evaluation of how HUMS can improve the availability and operational readiness and reduction in maintenance cost that leads to the development of cost model and (3) a use of case studies to evaluate degradation of systems under consideration and how their continuous monitoring can help reduce the maintenance cost. A cost modelling study presented a simple and effective method to analyse the financial implication of integrating HUMS system was proposed for military land vehicles. The model provides logical steps to estimate the yearly repair costs, operational availability and the overall costs to understand the financial implication of HUMS integration over the whole service life. The model was also used to assess the financial viability of integrating HUMS in other military platforms e.g. light armoured vehicle, Piranha and Main Battle Tank, Challenger 2. In both the cases, the analysis showed significant financial savings in the long term. A case study was conducted on two different military vehicles to identify the frequency of different systems and sub-systems failures. The 20 challenger 2 and 40 Piranha were studied over the period of 10 years of service time. Study has found that cooling-, lubrication- and the suspension- system were the mostly affected systems in those particular vehicles. An experimental protocol was developed to study the failure detection techniques for the suspension system. The frequency response function was used to identify the failure of the damper and hence the suspension system. The study has observed the changes in the resonance frequency of the failed suspension system with different excitation magnitudes. Effect of vibration waveform was observed to be negligible. However, the small changes in the resonance frequencies using different magnitudes of base excitation seems to suggest the excitation magnitude has the potential to identify the failure based on the frequency response function.Another experimental protocol was developed to examine the failure detection technique for the cooling system of the military vehicle. When the failure was introduced to the cooling system, the significant variations in the temperature were observed for all the engine running conditions at the lab as well as the test with the vehicle running in the field. The variations observed in the temperature measured in different locations in the cooling system could be used to diagnose an early stage of failure in the cooling system, and it can be used to take a preventive action before the actual failure occurs.
Open Access
Human vs non-human bone: identification and differentiation of fragmented skeletal remains using non-destructive methods
(Cranfield University, 2018) Corrieri, B.; Marquez-Grant, Nicholas; Rogers, Prof K.
Fragmented human and non-human bones can be found in forensic contexts, such as mass disasters, mass graves, and crime scenes, as well as in archaeological deposits. When fragmented skeletal remains are found, one of the first questions asked is whether or not the fragments are human or non- human. If none of the diagnostic features is visible, the origin of the fragments may be difficult to assess. Most of the methods currently employed to identify the origin of bone fragments, such as microscopic and biomolecular methods, are invasive and time consuming. The aim of the research presented in this thesis was to explore the potential of non-destructive procedures, such as GIS (Geographic Information System) software, morphological examination and Micro-Computed Tomography, in determining whether or not a bone fragment is human. These techniques were applied on skeletal features not commonly used for the human-nonhuman bone differentiation. Cranial suture patterns, cranial curvature and rib shaft curvature were assessed and measured using a GIS software. In addition, the morphology of the occipital condyles and the linea aspera of the femur were investigated and compared between human and non-human species. Finally, primary nutrient foramina and cross-sectional shape of long bones were analysed using micro-CT. More than 700 human and non-human bones were used; the non-human species selected are the ones whose remains are likely to be found in forensic or archaeological contexts in the United Kingdom. Most of the bone features considered and the procedures used in this study proved to be reliable for the differentiation between human and non-human fragmented bones. Blind tests performed on fragments whose human or non-human origin was not known further demonstrated the applicability and effectiveness of the methods and features explored in this study. The results of this research provide a valuable contribution to the fields of forensic anthropology, bioarchaeology, and comparative anatomy.
Open Access
Hydroxy-terminated polyether binders for composite rocket propellants
(Cranfield University, 2007-04-27T15:29:39Z) Caro, R; Bellerby, J
Propellants based on cross-linked Hydroxy Terminated PolyEther (HTPE) binders are being used as alternatives to Hydroxy Terminated PolyButadiene (HTPB) compositions. HTPE propellants have similar mechanical properties to HTPB propellants but they give a less severe response in ‘slow cook-off’ tests for IM compliance. A literature review is presented on the development and properties of HTPE propellants in an attempt to place them in relation to recent trends in Insensitive Munitions. To gain a better understanding of the behaviour of HTPE propellants an HTPE pre-polymer and a range of binder network samples with different NCO/OH equivalence ratios, with and without plasticizer, have been synthesised and characterised by a range of techniques. The thermal decomposition of the HTPE binder network and propellant samples were also studied. Desmodur N-3200 was used as a curing agent and n-BuNENA as an energetic plasticizer. Similar analyses were performed on analogous HTPB pre-polymer and binder network samples and the results were compared with those obtained for the corresponding HTPE samples. Two kinds of HTPE propellant were manufactured containing HTPE pre-polymer, n-BuNENA, 2NDPA and either AP or AP+PSAN as oxidiser. Also HTPB propellant was prepared. Small cook-off test vehicles (SCTV) were filled with HTPE and HTPB propellants and slow cook-off tests were performed. In contrast to HTPB binders, which become harder during slow heating, it was found that the HTPE binders soften under the same conditions. This behaviour is possibly due to chain scission of the soft and hard segments of the HTPE polymer matrix. Thermooxidative processes and reactions of the energetic plasticizer decomposition products are believed to be the responsible for the scission of the polymeric matrix. From the binder characterisation and slow cook-off results it is concluded that there is a relation between the degree of polymeric matrix scission during slow heating and the violence of the response at the point of self ignition. This underlies the main difference between HTPB and HTPE propellants in slow cook-off. While HTPB compositions become harder and more brittle, HTPE propellants become softer and have a lower surface area at the self ignition point.
Open Access
Interfacial and durability aspects of extrinsic Fabry-Perot interferometric sensors in carbon fibre composites
(Cranfield University, 2003-09) Etches, J A; Fernando, G F
This thesis is concerned with the interfacial and durability aspects of Extrinsic Fabry- Perot Interferometric (EFPI) sensors embedded in carbon fibre reinforced composites. Fibre optic sensors are being used in many long term applications and, as is the case for all sensor types, the ability of the EFPI sensors to monitor accurately the measurands of interest over the lifetime of the structure must be proved. Therefore, the aim of this work was to examine the interface between the EFPI sensors and the structures, and then to evaluate the durability of that interface and the sensors. The first stage was an examination of the EFPI sensors including the method of manufacture, interrogation option and inherent strength of the sensors. It was found that the sensors have a very low tensile load to failure (~0.5 N). This was improved by using a resin reinforcement, which was applied to the capillary ends. However, this had implications for the overall sensor size and that influenced their embedment suitability. The second stage was interfacial characterisation; this was achieved through the examination of the surface energy of the sensors, carried out by contact angle measurements; and the interfacial shear strength of the sensors to matrix, using a new variation on the single fibre pull-out technique that involved the use of optical fibres and composite prepreg. Overall, it was found that the silane treatment of the fibres increased the surface energy but for the interfacial shear results the data was less conclusive due to the scatter present within the results. The durability of the sensors was examined through their embedment into carbon fibre composite samples and exposure to tension/compression fatigue loading. From initial quasi-static work it was found that the embedment of the sensors had no significant effect on the composite samples. However, the sensors failed at a strain levels of 0.4% in tension and at 1.1% in compression; the compression strain level was at the point of composite failure. Under fatigue loading the sensors could survive a million cycles at R=-1 at a max stress level of 156 MPa and maintain their reliability. If the tensile loading was increased then the sensors would fail within a few thousand cycles. However, if the compressive stress was increased the sensors survived but the reliability was affected. Overall, it was felt that with some improvements to the sensor design they should be able to survive and provided useful data when exposed to axial tension/compression fatigue regimes.