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Understanding supply chain knowledge mobilization barriers from the middle‐range perspective: an empirical investigation of Argentina's agri‐food industry
Get PDFDespite considerable research attention to supply chain knowledge mobilization (KMob) barriers, understanding of why, how, and when they emerge in practice remains limited. We address this knowledge deficit by using middle‐range theory (MRT) as a theoretical lens to examine supply chain KMob barriers in their naturally occurring environment. Drawing on 42 in‐depth, semi‐structured interviews with Argentinian agri‐food supply chain (AFSC) practitioners, we present novel insights into the emergence of AFSC KMob barriers. First, our findings indicate the prevalence of 11 individual, intra‐organizational, and inter‐organizational KMob barriers in Argentinian AFSCs. Second, Argentina's political, economic, social, technological, legal, and cultural (PESTLC) environment contribute to these barriers. For example, the cultural environment, characterized by strong hierarchy and weak intellectual autonomy, may have negative effects on AFSC practitioners' KMob behaviors and perceptions, resulting in resistance to knowledge sharing, while long‐term political and economic instability poses challenges for intra‐ and inter‐organizational KMob. Third, these 11 KMob barriers elicit both semantic and pragmatic knowledge boundaries that thwart AFSC KMob. Our study extends the applicability of MRT to supply chain KMob research and provides a framework for better understanding KMob barriers. The study has important implications for agricultural research institutions and focal companies of local AFSCs.Journal of Business Logistic
Evaluating transcriptomic and metabolomic adaptations to heat stress in brassica napus (oilseed rape)
No full textHammond, John - Associate Supervisor
Anastasiadi, Maria - Associate SupervisorOilseed rape (Brassica napus) is an essential oilseed crop, accounting for
approximately 12% of the world’s vegetable oil production. Its ability to adapt to
various climates, has made it one of the predominant oil crops in Europe.
Previous research on Brassica species has shown a negative relationship
between heat stress and seed yield and quality. To date, only few studies have
addressed the impact of heat stress on the transcriptome and metabolome of B.
napus especially during the flowering stage and the underlying cellular
mechanisms are still poorly understood. To address this, combining genetic
studies with different omics approaches will provide the means to explore the
intricate responses arising following exposure to heat stress and accomplish a
system-level understanding of how heat stress alters growth and metabolism of
oilseed rape.
This thesis presents (i) a comprehensive review of the impact of heat stress on
the physiology and genetics of B. napus with a focus on the reproductive stages,
along with the mechanisms involved in heat stress response. (ii) A heat treatment
experiment simulating a heatwave during the flowering stage of B. napus, which
caused a significant transcriptional and metabolic changes in buds and leaves,
including the down-regulation of many respiratory pathways. RNA-seq analysis
showed that heat stress resulted in the differential expression of many genes
involved in key biological processes such as heat shock, regulation of cellular
processes, transcription factors, cell wall remodelling, sugars and secondary
metabolites transport and metabolism. At the metabolomic level, heat stress
increased the content of carbohydrates (glucose, fructose and sucrose) and
aliphatic glucosinolates (gluconapin, progoitrin) in the leaves but decreased the
content of the indolic glucosinolate (glucobrassicin). Additionally, heat treatment
also reduced yield and altered oil composition. (iii) This thesis also presents a
Cytoscape plugin to visualise genes-TFs interactions in a user-friendly
environment. Using the plugin, the top DEGs identified in the heat treatment
experiment were found to interact with a wide range of TFs, with members of the
MYB, NAC, and WRKY families showing the highest number of gene interactions.
Overall, these results revealed important components of heat stress response
and tolerance mechanisms in B. napus. The identified genes and metabolites
could form the theoretical basis for potential biotechnological applications and a
genetic resource for further studies towards the identification and development of
high-yield and nutritious varieties that can cope with the heat predicted by the
global climate change.Biotechnology and Biological Sciences Research Council (BBSRC)PhD in Environment and Agrifoo
High performance rechargeable aluminium ion batteries enabled by strategy of covalent organic frame material
Get PDFEmerging rechargeable aluminium-ion batteries (RAIBs) are a sustainable option for the next generation of low-cost, high-safety and large-scale energy storage technologies. While the unsatisfying availability of traditional inorganic materials has limited the development of RAIBs, the advance of organic materials is expected to be a breakthrough towards high-performance cathode. However, the existing extensive research often focuses on the selection of appropriate organic monomers or stay in the tentative stage of preliminary polymerization. It is difficult to break through the inherent characteristics of the instability of small organic ones and the easy aggregation and accumulation of macromolecular polymers, which is no doubt ignoring the huge potential of organic compounds for structural design at the molecular level. In this connection, our study demonstrates a material design strategy that introduces active functional groups to small molecular monomers and polymerizes them into REDOX active covalent organic framework (COF) with multiple N-containing groups. Theoretical simulations and ex-situ analysis revealed the key function of C-N and C=N as active sites for reversible storage of AlCl2 + ions. In addition, the macro-ring frame brings enhanced structural stability and environmental tolerance for COF in complex electrolyte, resulting in significantly improved electrochemical performance. At 1 A g−1, it exhibits a high specific capacity of 161.2 mAh g−1 and an excellent cycle life of approximately 100 % coulombic efficiency after more than 3,000 cycles. This work fully demonstrates the operability of the design strategy to synthesize COF from small molecular organics by introducing reactive functional groups and its great potential in the role of cathode materials in RAIBs. The success meanwhile provides an inspiration for the development of COF-based organic battery system in large-scale energy storage.This work was supported by Opening Project of Guangxi Key Laboratory of Calcium Carbonate Resources Comprehensive Utilization (Grant No. HZXYKFKT202206), Guangxi Natural Science Foundation (Grant No. 2024GXNSFFA010003), Project entrusted by enterprise (Grant No. HX20210521 and Grant No. HX20230264) and Hezhou University Research Project (Grant No. 2023ZDPY01).Chemical Engineering Journa
Cascade network stability of synchronized traffic load balancing with heterogeneous energy efficiency policies
Get PDFCascade stability of load balancing is critical for ensuring high efficiency service delivery and preventing undesirable handovers. In energy efficient networks that employ diverse sleep mode operations, handing over traffic to neighbouring cells' expanded coverage must be done with minimal side effects. Current research is largely concerned with designing distributed and centralized efficient load balancing policies that are locally stable. There is a major research gap in identifying largescale cascade stability for networks with heterogeneous load balancing policies arising from diverse plug-and-play sleep mode policies in ORAN, which will cause heterogeneity in the network stability behaviour. Here, we investigate whether cells arbitrarily connected for load balancing and having an arbitrary number undergoing sleep mode can: (i) synchronize to a desirable load-balancing state, and (ii) maintain stability. For the first time, we establish the criterion for stability and prove its validity for any general load dynamics and random network topology. Whilst its general form allows all load balancing and sleep mode dynamics to be incorporated, we propose an ORAN architecture where the network service management and orchestration (SMO) must monitor new load balancing policies to ensure overall network cascade stability.Engineering and Physical Sciences Research CouncilThe work is supported by EPSRC CHEDDAR: Communications Hub For Empowering Distributed ClouD Computing Applications And Research (EP/X040518/1) (EP/Y037421/1).GLOBECOM 2024 - 2024 IEEE Global Communications Conferenc
Pilots’ training backgrounds affecting the attribution of event causal factors and airline safety management
Get PDFFor safety management in diverse aviation operators, it is necessary to investigate how different cultural factors interact in flight operations. Whilst prior studies have evaluated between-group cultural differences, there remains a research gap on whether within-group subcultural differences challenge the assimilation of people into the safety culture of the wider group. Cultural differences in how causal factors are perceived in the context of systemic safety deficiencies can affect the implementation of safety management strategies. In the present study, pilots from airline-sponsored, self-funded, and ex-military initial training backgrounds were invited to categorise an identical set of aircraft accident causal factors using the Human Factors Analysis and Classification System (HFACS). Results from 121 participants found significant differences amongst the three groups in the attribution of human factors conditions to organisational-level and supervisory-level categories. Significant associations amongst HFACS categories also differed amongst the three professional groups, with a considerable number of same-level associations found between ‘Preconditions for Unsafe Acts’ at the same level. Familiarity with organizational cultures was considered to impact the perception of causal factors. The finding of same-level associations presents a new contribution to the theoretical basis of the HFACS taxonomy, calling for a conceptual change in the directionality of causal sequences. The results suggest that the direction of safety remedies for different parts of the organisation is dependent on perceived relevance, which differs amongst subcultural groups. Findings are relevant to industry, particularly international airlines with diverse employee subcultural groups, for the implementation of safety management systems.Journal of Air Transport Managemen
Investigation of aircraft auxiliary power unit acoustic signatures for condition monitoring
Get PDFAli, Fakhre - Associate SupervisorThe auxiliary power unit (APU) of an aircraft is a key system responsible for
providing electrical and pneumatic power during ground operations and in-flight
emergencies. APU failures can result in delay or cancellation of a flight and fault
diagnostic practices are in place to identify the cause of failure. The existing
strategies generally require human intervention to identify the fault by traversing
through a troubleshooting manual and examining the data acquired from multiple
intrusive sensors. The complete process is cumbersome and prone to
misjudgement; fault identification in its entirety may not be possible due to limited
sensor coverage. Incorporating additional sensors may not be feasible due to
accessibility issues, space constraints and certification requirements. However,
incorporating microphones, which have previously been used for noise source
characterization and verification of noise abatement solutions, is a promising non-
intrusive approach. This PhD focuses on ascertaining the potential of
microphones for fault detection / identification and condition monitoring of an
aircraft APU. The research has been based on the far-field and near-field acoustic
data acquired from Cranfield University’s Boeing 737-400 aircraft and the aim has
been to determine the degradation / faults that can be detected using
microphones. While addressing this aim, a far-field noise model has been
developed for sensitivity analysis, near-field data has been analysed,
classification / regression models have been proposed and an acoustics-based
scheme for ignition system monitoring has been conceived. The results suggest
that the far-field acoustic data is not suitable for condition monitoring, and the
near-field microphones are unable to monitor tonal frequencies for monitoring the
gearbox and bearing. However, there is a huge potential in using microphones
for monitoring the lubrication system, pneumatic system components and ignition
system for faulty / degraded conditions. The proposed methodologies have online
capability and require only a limited set of microphones inside the APU
compartment.PhD in Transport System
Cybersecurity of the internet of things: a development of security methods based-distributed sensors for industrial applications
Get PDFInalhan, Gokhan - Associate SupervisorThe nature of communicating in the heterogeneous Internet of Things (IoT) environment
and the disparity in resource capabilities between IoT nodes make it difficult to establish
the necessary security in connections. In contrast with conventional networks, most IoT
components have limited energy and computational capacity and cannot support
complicated security schemes. IoT has been utilised extensively in sensing, controlling,
and computing for countless applications in numerous domains, including smart homes,
cities, transportation, communication, healthcare, and smart grids. Integrating IoT
technology for industrial applications requires security techniques for constructing
progressively secure, efficient, and adaptable new systems. Even though there are
numerous established methods for securing IoT applications, IoT networks face several
obstacles in adopting effective security solutions due to their resource-constrained and
limiting characteristics, such as limited memory, low cost, fewer computational
capabilities, and low power consumption. The IoT necessitates effective authentication
and detection mechanisms that protect security objectives and match its capabilities and
features. This study addresses the new IoT security challenges for distributed wireless
sensor networks (DWSNs). WSNs initiated this change by introducing unattended
wireless topologies comprising resource-constrained nodes, in which the radio spectrum
ceased to be the primary resource worthy of optimisation. Resource-constrained IoT
nodes are exposed to many unanticipated security threats not faced by traditional network
systems. Therefore, IoT cybersecurity is constrained by limited resources rather than an
absence of advanced security solutions and developing solutions compatible with IoT
device capabilities is imperative.
This thesis attempted to fill the gap by addressing the theoretical and practical aspects of
IoT/Industrial IoT (IoT) cybersecurity. A comprehensive evaluation of the literature in
the second chapter shows that several authentications, encryption, and detection schemes
have been developed to provide security and system integrity without efficiently
optimising security complexity to meet the constraints of resource devices.
A new mutual authentication scheme is proposed: a payload encryption-based
optimisation scheme (PEOS) for lightweight authentication on the Constrained
Application Protocol (CoAP). This incorporates the design of a scenario on the Contiki
OS that is included in the Cooja simulator to provide a realistic hardware environment to
analyse IoT applications. The test scenario was run several times under different data
sizes to investigate the impact of authentication schemes on the performance of resource-
constrained nodes. The results of the computational calculation are used to compare the
performance of resource-constrained nodes under our proposed scheme, a basic DTLS,
and schemes in previous work. The results show that our PEOS improves the DTLS
handshaking and retransmission processes, significantly reducing overhead without
impacting CoAP performance over distributed sensors. Furthermore, PEOS implemented
the parallel execution of S-Boxes in SubBytes, delayed MixColumns in the Advanced
Encryption Standard protocol, and successfully reduced the need for additional storage
registers. From the results, with a large payload size, the throughput of the proposed
scheme was improved by 8.7% compared to the existing PbMA by consuming 1550
microjoules under a 50-node random topology.
Finally, a novel detection approach, called customised intrusion detection (CID), was
proposed for heterogeneous IoT networks using federated transfer learning (FTL). The
proposed FT-CID model uses an improved grey wolf optimiser (IGWO) technique to
reduce noise and irrelevant features from a simulated IoT dataset. This incorporates the
design of a scenario on the Contiki OS to provide a realistic hardware environment in
which to analyse IoT applications. Advanced metering infrastructure datasets were
collected from the Contiki OS experiment under different data sizes and attack conditions.
Machine learning was used to validate the CID strategy computationally. Regarding
distinguishing abnormal from normal traffic, the results confirm exceptionally high
prediction accuracy compared with different ML algorithms. The proposed FT-CID
model yields 10.63% higher intrusion detection accuracy than the centralised CNN model
on the heterogeneous IoT network or the AMI applications.PhD in Aerospac
Stakeholder agency and grand challenge projects in forced displacement context
Get PDFGrand challenge projects (GCPs) address critical global issues such as poverty, climate change, COVID-19, and forced displacement. However, research reveals that many GCPs often yield limited results when managed through a top-down approach. In this research, we investigate how the agency of external nonmarket stakeholders (i.e., the project beneficiaries), can be useful in aligning GCPs to local needs for successful outcomes. Using participatory action research and interpretive structural modelling, we identify the key agency factors influencing the iterative, the practical–evaluative, and the projective dimensions of beneficiaries’ agency in forced displacement grand challenge context. We show how beneficiaries’ agency influences project legitimacy and urgency. Our findings also demonstrate that active beneficiaries’ involvement can significantly improve project outcomes, emphasising the need for GCPs to meaningfully incorporate beneficiaries’ perspectives to enhance impact and sustainability. Finally, our research provides practical insights for project managers and policymakers on engaging stakeholders in complex, high-stakes contexts.UK Research and Innovation, Arts and Humanities Research Council (AHRC) AH/W00979X/1.EURAM 2025 Annual Conference: Managing with purpos
High-precision machining behavior of the single crystal scintillator, bismuth germanate (Bi4Ge5O12)
Get PDFThis study focuses on understanding the machinability of a single-crystal scintillator, Bismuth Germanate (BGO), a material widely used in Time-of-Flight Positron Emission Tomography (ToF-PET). The micromachining process of such a hard, brittle material presents several challenges, particularly in maintaining surface integrity without inducing fractures or microcracks. In this work, we employed the Johnson-Holmquist 2 (JH-2) material model to simulate the micro-milling process of BGO. Experimental data from quasi-static uniaxial compression and split tests were used to estimate the key parameters for the JH-2 model. The simulation results closely aligned with experimental outcomes, confirming the reliability of the model in capturing the mechanical behavior of BGO under stress. Simulations were conducted with different machining parameters, successfully replicating the conditions observed in practical machining tests. Our findings demonstrate the impact of feed rate and depth of cut on the machinability of BGO, validating the use of the JH-2 model of this material. Looking ahead, this robust computational framework offers the potential to further optimize the machining process, ultimately enabling the production of high-performance heterostructures for scintillator applications in TOF-PET.Engineering and Physical Sciences Research Council (EPSRC)This work was supported by the UK Engineering and Physical Sciences Research Council (EPSRC) grant EP/S013652/1 for Cranfield University. The authors would like to thank Dr D. Johnson and Mrs C. Kimpton for SEM measurements.Materials Today Communication
Unveiling the hurdles confronting compressed biogas plants: a comprehensive research analysis for sustainable energy solution
Get PDFThe purpose of this work is to identify and analyze the key important barriers to uptake the compressed biogas (CBG) plants in India for enhancing their role as a sustainable energy source. Initially, the barriers are identified from the past academic literature using literature review process and are then validated through the fuzzy Delphi method with expert opinions. The finalized barriers were then categorized into cause effect relationship and ranked for strategic decision making by policy makers, investors, and industry practitioners. We employed the weighted influence non-linear gauge systems (WINGS) method to find hierarchical relationships and determine the priority of these barriers. The findings provide a strategic roadmap for policymakers, investors, and industry stakeholders to enhance CBG adoption through supply chain improvements, financial incentives, public awareness campaigns, and regulatory streamlining. By systematically identifying, linking, and ranking interrelated barriers, the study develops a structured and data-driven framework that provides actionable strategies for accelerating the adoption of compressed biogas (CBG) plants in India.Discover Applied Science