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Robust deepfake detection through the AI-Guard mobile app for Real-Time image identification
No full textThe proliferation of deepfake technologies has created an urgent need for robust, real-time detection systems capable of verifying image authenticity, particularly in mobile environments. This paper presents a scalable deepfake image detection framework integrated into the AI-Guard mobile application. Our approach leverages fine-tuned, computationally efficient convolutional neural network (CNN) architectures, including VGG19, InceptionV3, Xception, EfficientNetB0, ResNet50, and MobileNetV3Large. Trained on a large-scale, balanced dataset of over 450,000 real and fake images sourced from six publicly available datasets, the models incorporate advanced preprocessing, adversarial data augmentation, and optimized training pipelines. Among these, VGG19 achieved the highest generalization performance with 98.9% validation accuracy and 93.2% accuracy on previously unseen real-world data. The system supports real-time inference via a REST API, enabling practical mobile deployment with low latency. To support transparency and reproducibility, the curated training dataset has been made publicly available through our institutional repository. Our results demonstrate that AI-Guard offers an effective, deployable solution for forensic image verification, contributing to countering misinformation and enhancing trust in digital media.Human-Intelligent Systems Integratio
Intelligent transformation and green development: a double debiased machine learning evaluation of china’s IIP initiatives
No full textIn promoting the transformation, upgrading, and green development of traditional industries the Chinese government has been introducing Integration of Informatization and Industrialization Pilot (IIP) initiatives based on intelligent manufacturing and the green economy. As such this study examines the impact of China’s IIP policy on the green development of publicly listed manufacturing firms by applying both Difference-in-Differences (DID) and double debiased machine learning (DDML) models to a dataset that spans the period 2007–2022. The evidence suggests that the IIP policy initiative significantly improves firms’ green development via the mediating effect of intelligent transformation. Robustness checks, including DDML model regression and Propensity Score Matching-DID (PSM-DID) with nearest neighbour matching, consistently demonstrate significant improvements in environmental efficiency and productivity due to the IIP. Moreover, these effects are notably pronounced in the Yangtze River Economic Belt, heavily polluting industries, and larger firms. This research addresses a gap in micro-level policy analysis, highlighting the potential of intelligent manufacturing to promote sustainable practices. By offering both theoretical and practical insights, the findings guide policymakers and businesses in leveraging informatization and industrialization for green development.Annals of Operations Researc
Impact of integration on procurement of urgent goods and serviceswithin the public healthcare sector
No full textSaghiri, Soroosh - Associate SupervisorUrgent procurement in healthcare has been under-researched despite its critical
role in ensuring business continuity and timely patient care. This study explores
how procurement integration impacts urgent procurement by combining a
systematic literature review with secondary data analysis from the UK
government’s Model Hospital database. The findings indicate that while
procurement integration is well understood in planned contexts, it remains
insufficiently addressed in urgent situations, particularly unpredictable, patient-
specific requirements.
Two key contributions emerge from this research: first, it differentiates between
standard and urgent procurement processes, emphasising the latter's unique
challenges in healthcare. Second, it highlights the limited integration of urgency
within procurement strategies, with procurement often overriding clinical input. A
theoretical framework is proposed to bridge this gap, drawing on case studies of
eight healthcare providers (five public and three private) and interviews with 30
professionals, including clinicians and procurement managers.
The results show that effective communication integration is essential for
improving urgent procurement outcomes, enabling faster response times and
fostering stakeholder collaboration. The study underscores that previous
procurement successes enhance future urgent procurement performance, while
failures reduce responsiveness. Additionally, conflicting objectives between
clinical and procurement teams and a lack of tailored decision support systems
(DSS) hinder urgent procurement efficiency.
This PhD thesis calls for developing a DSS designed to streamline urgent
procurement processes by improving communication, transparency, and
alignment of objectives. Integrating contingency and socio-technical systems
frameworks with qualitative data offers a robust foundation for future research
and practical solutions to optimise healthcare procurement, particularly in the UK
public healthcare sector.PhD in Leadership and Managemen
Integrated NDI-based Controller and Incremental Control Allocation for an eVTOL
No full textLu, Linghai - Associate supervisorThe concept of urban air mobility (UAM) has been proposed to address the transport problems of congestion and pollution in ever-growing urban conurbations. Mature fixed wing aircraft technologies have many constraints that limit their applicability for UAM hence piloted all electric vertical take-off and landing (eVTOL) vehicles known as eVTOL ‘air-taxis’ provide a
promising option being lighter, quieter, potentially having net zero emissions and with lower
operating costs. Furthermore, their higher bandwidth thrust actuation allows for novel config urations. However, one challenge of eVTOL aircraft operation is their strong nonlinear flight
dynamics since they operate over a wide range of operating envelope. One particularly chal lenging eVTOL configuration is the Lilium jet, a fixed-wing, over-actuated vectored thrust,
canard light sports aircraft. However, its canard configuration can destabilize the short-period
mode requiring fly-by-wire stability augmented flight control systems. A second challenge of
this configuration is the coupling between the aerodynamic surface control and the vectored
thrust makes control allocation (CA) during transition very difficult. A third challenge of this
configuration is its high degree of over-actuation presents a challenging CA. Finally, a fourth
challenge of the eVTOL configuration is that the vectored thrust results in nonlinear effector
mapping preventing the direct use of classical CA approaches. In order to address the control
challenges of the Lilium-style eVTOL, a novel full-envelope controller is presented which em ploys a generic control architecture applicable to piloted, semi-automatic and fully automated
flight. The full-envelope controller consist of an aircraft-level controller which produces an
overall control demand and a CA scheme which allocates the overall control demand to indi vidual redundant effectors. The CA scheme also performs control error minimisation, control
channel prioritization and control effort minimization. The aircraft-level controller adopts a
modular approach, consisting of a main inner-loop nonlinear dynamic inversion (NDI) con troller which cancels the bare airframe dynamics and an outer-loop proportional-integral (PI)
linear controller which together addresses several of the eVTOL operation challenges. The
inner-loop NDI controller is a velocity controller while the outer-loop PI controller is an at titude and navigation position controller which together are used for hover/low speed control
and forward flight. This thesis proposes and initially conceptually tests three real-time CA ap proaches for transforming a nonlinear CA problem to a linear problem and then applies active
set linear CA technique to address all the remaining challenges of the eVTOL configuration.
This thesis fully verifies one of the CA approaches on a full six-degrees-of-freedom model
version of the eVTOL aircraft. Simulation results clearly demonstrates that the controller has
reasonable disturbance rejection, can guarantee stable flight in case of severe actuator satura tion and has satisfactory compliance to typical mission tasks for this class of vehiclePhD in Aerospac
On a novel co-rotating synchronous turbine mode operation in a centrifugal compressor
No full textSee also: https://doi.org/10.1115/1.4070125
Copyright © 2025 by Rolls-Royce plcA novel co-rotating, synchronous, reverse flow (RF) turbine mode operation in a centrifugal compressor (CC) is investigated, and methods to enable this mode, its working principles, flow field features, and key performance characteristics are described. This is done by using three-dimensional (3D) Reynolds–averaged Navier–Stokes (RANS) flow field simulations on a simplified variant of the NASA High Efficiency Centrifugal Compressor (HECC) geometry, which represents a typical state-of-the-art design practice. The novel co-rotating turbine mode is elucidated by first considering the baseline contra-rotating, reverse flow turbine mode as would be expected from the conventional four-quadrant CC operation map. This baseline contra-rotating turbine mode is also hitherto undescribed in the literature for CC. Therefore, the flow field and performance metrics in the baseline contra-rotating mode are utilized to provide insights into the possibility of engineering design elements that can enable the novel co-rotating turbine mode. The novel co-rotating, turbine mode is found to be enabled by the introduction of a suitable swirl generation mechanism that will direct the flow onto the impeller wheel suction side to give it a rotational impulse to spin from the suction to the pressure side as in nominal operation. The flow expansion through the reversed impeller wheel flow path with radius reduction enables power production. In the novel co-rotating, turbine mode, the flow leaves the impeller wheel in the same direction as it enters because of the direction of rotation and impeller inlet flow angle. However, this does not significantly impact power production because of the reduced radius weighting of the absolute swirl at the impeller inlet. An exemplary co-rotating turbine mode enabling configuration with 45 deg rotated diffuser vanes is found to handle up to 46% higher reverse flow and yield 6.25% higher peak power output even with a 16% lower absolute swirl velocity change as compared to the baseline contra-rotating mode. Additionally, the novel mode indicates better low speed power profile and wheel terminal speed as well. Alternative embodiments to enable the co-rotating mode like drilled feed ports and guide vane arrangements are discussed in the work. The hitherto undescribed co-rotating turbine mode operation is unique in its ability to produce and absorb power in the same shaft for bladed turbomachinery. Therefore, purposeful utilization of this mode could enable the design of better, robust, optimized systems for aerospace and energy applications.The authors would like to express their gratitude to Rolls-Royce plc. for supporting this research. The work was carried out under InnovateUK—Aerospace Technology Institute (ATI) Project PINES, Reference No. 113263.Journal of Engineering for Gas Turbines and Powe
De-risking of a high-speed intake distortion facility using a small-scale pilot rig
No full textSession: High-Speed Inlets, Isolators and Nozzles I
Copyright © 2026 by Cranfield University.This paper presents the development of a sub-scale pilot rig (Mini HI-Sim) designed to de risk the operation of a large-scale, high-speed intake distortion facility (HI-Sim). The Mini HI-Sim replicates key aerodynamic features using a vacuum-driven aspirated configuration able to provide onset Mach numbers up to 1.65. This paper assesses the operating performance of the rig and compares it to estimates of operational runtime based on compressible flow theory and polytropic expansion. The study demonstrates that the runtime and flow uniformity are sensitive to vacuum level and speed of the fast-acting valve. Flow visualization using tuft tracking and image processing confirmed the presence of counter-rotating vortices in the radial exhaust which had been observed in previous computational work of the full-scale rig, offering a preliminary and qualitative validation of the radial exhaust design. Preliminary CFD analysis showed that re-pressurization of the working section was caused by an excessive geometric contraction in the exhaust, which increased the static pressure around the enclosed jet in the working section and prevented the normal shock from being fully displaced downstream. Removing this contraction yielded a uniformly low plenum pressure, improved flow extraction, and enabled the intended Mach-number distribution in the working section. Overall, the Mini HI-Sim offers a cost-effective platform for aerodynamic and instrumentation de-risking, supporting the development of robust supersonic intake systems for future propulsion applications.The authors would like to thank the Defence Science and Technology Laboratory (Dstl) and Rolls-Royce plc. for supporting this research.AIAA SCITECH 2026 Foru
Data for manuscript titled "Defect depth estimation using through-transmission pulsed thermography: A numerical and experimental investigation"
No full textRaw thermograms for pulsed thermography in the reflection and transmission modes. Grant number: EP/P027121/1Through-transmission pulsed thermography is widely recognised for offering higher defect resolution than reflection mode, yet its development has been hindered by challenges such as quantifying defect depth. This study addresses the depth quantification gap by introducing a novel depth estimation technique based on the relationship between defect depth and the Fourier number. The method is validated through both finite element modelling and laboratory experiments using calibration samples with embedded air-gap defects at known depths. Results show that depth estimation accuracy improves as defects approach the backwall, consistently across both simulation and experimental environments. Finite element analysis also demonstrates that the proposed technique outperforms the log second derivative method typically used in reflection mode. These findings advance the capability of through-transmission thermography for precise subsurface defect characterisation.Sun Resource
Beets beyond sugar: potential and limitations of sugar beet pulp as a feedstock for biorefineries
No full textSugar beet (SB) is a major sugar crop in the European Union and the United States, primarily cultivated for the commercial production of table sugar. Post-extraction of sucrose, the fibrous fraction which remains is called sugar beet pulp (SBP). SBP is rich in structural carbohydrates such as cellulose, hemicellulose and pectin containing glucose, arabinose and galactouronic acid as their respective monomeric units. SBP is a renewable source of fermentable sugars that constitute about 85 % of total carbohydrates. Leveraging SBP as a substrate for a biorefinery supports circular bioeconomy principles by simultaneously reducing agricultural waste and enabling the sustainable production of value-added chemicals. This review highlights current advances in SBP valorization, beginning with an overview of SB processing and waste generation, followed by a critical assessment of pretreatment strategies that enhance carbohydrate accessibility. Particular attention is given to emerging routes for the bioconversion of arabinose and galacturonic acid, which together represent more than half of SBP’s fermentable fraction yet remain significantly underutilized in industrial biotechnology. Microbial pathways, metabolic engineering interventions, and fermentation approaches enabling the production of value-added compounds such as arabitol, 2,3-butanediol, ascorbic acid, mucic acid and prebiotics are examined in detail. The review concludes by addressing current challenges and identifying research gaps to unlock the full potential of SBP within integrated biorefinery systems.VK and RPS acknowledge support from Magan Centre for Applied Mycology [Research England Expanding Excellence in England (E3) by UKRI (UK Research and Innovation)].VK and FC are grateful to UKRI Biological Sciences Research Council (BBSRC) grant BB/Y008332/1.Industrial Crops and Product
Top management involvement in key account management: a contingency model
No full textPrior, Daniel - Associate SupervisorKey Account Management (KAM) plays a strategic role in driving long-term
customer value, yet its implementation remains challenging. While prior research
recognises the importance of Top Management Involvement (TMI) in KAM,
limited attention has been paid to what drives such involvement, how it manifests
in practice, and how it is shaped by contextual contingencies. This study
addresses these gaps through an abductive, multi-case research design
involving seven organisations. It identifies 19 drivers of TMI, categorised along
proactive–reactive and strategic–operational–individual dimensions. TMI is found
to manifest across three behavioural domains: displayed commitment, decision-
making approach, and interaction style. Importantly, the study demonstrates that
structural, environmental, cognitive, and operational contingency factors
moderate the relationship between TMI drivers and executive behaviours. These
findings make theoretical contributions by refining and extending the
conceptualisation of TMI, increasing our understanding of how personal traits
influence TMI, illustrating its dynamic nature, and challenging the assumption that
TMI is inherently beneficial to KAM performance. The study also offers practical
insights for aligning executive involvement with KAM demands. It presents a set
of ten role templates for executive involvement in KAM and concludes with
limitations and suggestions for future research.PhD in Leadership and Managemen
Ammonia partitioning and recovery from industrial wastewater - exploring precipitation, stripping, and sorption technologies
No full textJefferson, Bruce - Associate SupervisorCircular economy in wastewater management is increasingly applied, with
ammonia recovery playing a critical role. Established ammonia partitioning
technologies, being precipitation, typically as struvite, stripping and scrubbing,
and sorption, have been predominantly applied to manure, anaerobic digestate,
urine and municipal wastewater. Industrial effluents also hold potential for
ammonia recovery and have been increasingly targeted by research. These
effluents comprise a wide category of wastewaters with diverse physicochemical
characteristics, generated by different sectors, including food/drink processing,
mining, agro-industrial processes, manufacturing, metallurgy, etc. Some of these
effluents contain high ammonia loads alongside significant concentrations of
ions, metals, and recalcitrant organic compounds, contributing to complex
chemical compositions that can pose challenges for conventional recovery
technologies. Despite the increasing focus on industrial wastewaters, there
remains limited understanding of how to effectively select and operate recovery
technologies, based on the effluent composition and desired recovery outcomes.
This research aimed to advance the understanding of how several physicochemical factors impact the mechanisms enabling ammonia partitioning into gas,
liquid and solid phases, in order to establish optimum transfer pathways. The key
knowledge gaps addressed in this research were i) determination of main criteria
for ammonia recovery technology selection for a range of industrial wastewaters,
ii) understanding the feasibility and recovery performance of struvite precipitation
and ammonia stripping at demonstration scale from distillery wastewater, iii)
understanding and quantifying the impact of transition metals and acidic organic
compounds on ammonia stripping, iv) assessment and comparison of ammonia
separation performance via ion and ligand exchange media and influence of
operation parameters (e.g. pH, buffer capacity, metal load, N concentration). The
findings are utilised to generate an informed decision process for
technology/strategy selection and the operational requirements and potential
challenges posed by selected factors, with relevance for industry stakeholders,
technology providers, and consultants. A specific focus was placed on distillery
wastewater as a case study, a sector concerned with ammonia management and
potentially suitable for recovery, particularly in Scotland.
A review of the literature found that struvite precipitation is the most widely
implemented method with industrial effluents, yet stripping and sorption
processes may be preferred for their ability to deliver versatile, ammonia-rich
solutions. The identified technology-selection criteria included the feed
concentration of ammonia and competing cations, and the struvite formation
potential. Based on the practical recommendations developed in this study, an
ammonia recovery strategy for distillery wastewater was established, integrating
anaerobic digestion with chemical precipitation and ammonia stripping coupled
with scrubbing. The performance of this treatment train had never been tested
before for filtered digestate of distillery effluent, addressing a key gap in
understanding for full scale applications. Demonstration scale trials allowed to
understand how the expected performance translated with real digested distillery
wastewater and to validate its feasibility. The results demonstrated its technical
viability, achieving 76% N removal and 80% P removal, while generating high-
quality struvite and ammonia sulphate solution. Moreover, the findings
highlighted the critical impact of pH and addressed operational challenges,
improving readiness for full-scale application.
Beyond distillery effluents, this thesis examined broader challenges in industrial
wastewaters treatment, addressing gaps identified in the literature review,
relevant for a range of industrial wastewaters, including from metallurgy and
agro/food processing. Specifically, the impacts of species found in some of these
effluents, such as transition metals (as Ni, Cu, Zn) and organic, acidic compounds
(as humic acids), on the stripping process were investigated. Results showed that
elevated levels of such species can reduce ammonia availability for stripping, via
complex formation and electrostatic interactions. This highlighted the need for
mitigation strategies to maintain stripping efficiency with these streams.
Additionally, the metal-ammonia bond potential was further explored to assess
ligand exchange (LEX) sorption mechanism as alternative to ion exchange (IEX),
a mechanism often limited by high concentrations of ammonia and competing
cations. Although various media have been tested in literature, comparative
studies on their performance under different conditions are lacking, along with
insights on how factors such as pH, transition metal and cations load can impact
their mechanisms and effectiveness. In this study, two zinc-hybridised sorption
media were tested and benchmarked against IEX media, in synthetic and real
wastewaters (distillery, municipal). The results showed effective removal,
although limited by self-inhibiting pH changes, with a zinc-hybridised media
matching or exceeding IEX resin’s performance only when pH 9-10 was
maintained (75 meq N/g). pH, buffer capacity and Zn/Na loads were
demonstrated to be critical factors to enable or limit IEX and LEX mechanisms.
The findings established operational requirements for hybridized sorption media
and provided research directions for further improvement.
Overall, this work advanced knowledge on the impact of key species on ammonia
recovery technologies, with implications for industrial effluents treatment in
general and distillery wastewater management in particular. The findings
contributed to developing recommendations for selection and operation of
ammonia partitioning strategies, optimizing metal-hybridized sorption media, and
improving process feasibility for full-scale implementationPhD in Wate