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Dataset "Effect of temperature, relative humidity and incubation time on the mycotoxin production by Fusarium spp. responsible for dry rot in potato tubers"
No full textPotato is the fourth most consumed crop around the world. More than half of the potato crop is stored for three to nine months at cold temperatures (3-
10°C) for the fresh and seed market. One of the main causes of fresh potato waste in the retail supply chain is the appearance of fungal and bacterial rots
during storage, around 3-5% of the potato crop is lost every year. Dry rot is a fungal disease that mainly affects the potato crop during storage and is
responsible for a large volume of waste and associated economic losses. It is produced by Fusarium spp., such as Fusarium sambucinum and F. oxysporum.
Understanding the ecophysiology of these fungi is a key point to mitigate their occurrence under commercial storage conditions. Therefore, this work aimed
to elucidate the effect of three different temperatures (5, 10 and 15°C) and two different water activities (aw; 0.97, 0.99) on the ecophysiology and mycotoxin
accumulation of F. sambucinum and F. oxysporum in a potato-based semi-synthetic medium. The mycotoxin accumulation was then studied in vivo, in potato
tubers stored for 40 days at 8.5°C. Results showed that higher temperatures and aw enhanced fungal growth, lag time and mycotoxin accumulation in vitro.
Six different mycotoxins (r-2, HT-2, diacetoxyscirpenol, 15-acetoxyscirpenol, neosolaniol and beau-vericin) were detected in vitro and in vivo. Due to the long
period of time that potato tubers spend in storage, the fluctuations of environmental factors, such as temperature and relative humidity, could promote the
development of fungal rots, as well as mycotoxin accumulation. This could result in important food and economical losses for the potato market, as well as a
threat to the food safety of potato tubersInterreg NW
An investigation of monolithic nickel-based catalyst for clean hydrogen production with CCS technology: the effect of structure
Get PDFAt present, hydrogen is recognised as a carbon-free energy carrier, but its major production via the steam methane reforming (SMR) process requires further decarbonisation as a considerable amount of carbon dioxide is simultaneously emitted. Carbon capture and storage (CCS) techniques can be integrated with typical SMR to produce clean hydrogen. Previously, a novel structured catalyst (Ni/SiC-M) was developed, and it was highly active for SMR under low operating temperature and high gas space velocity. By integrating CCS techniques, this structured catalyst is promising to produce clean hydrogen, however, there is a lack of knowledge about the catalytic performance when CCS is applied, especially the effect of structure. In this work, the feasibility of producing cleaner hydrogen with monolithic catalysts (Ni/SiC-M) coupled with sorbent particles was discussed. Different modified structures were applied for performance evaluation with a fixed bed reactor, to better understand the relationship between the structure and the activity. The results showed that sorbent particles can adsorb most of the generated carbon dioxide, leading to a higher hydrogen purity; the limitation of internal mass transfer caused by high pressure drops can result in a decrease in catalytic activity, but the impact was limited. The pore size could be the key factor to influence the performance of structured catalysts.Fue
Understanding the societal legitimacy of the circular economy for the water sector.
Get PDFThe water sector employs Circular Economy (CE) principles through many
applications, such as the reuse and recovery of water, nutrients, and energy.
Although such applications are helpful to tackle increasing global water and food
demands, and help reach net zero emissions targets, there are many challenges
to achieving wide uptake. Societal-based and cultural-based challenges are
some of the least studied and most pressing barriers to address. Understanding
the perceptions of various actors towards CE applications has narrowly focused
on the acceptance perspective. However, perceptions may be better understood
by connecting CE applications with their institutional landscapes using the
theoretical framework of legitimacy. To date, the application of Legitimacy Theory
to CE applications has been limited.
This thesis aims to extend the prevailing theoretical thinking on legitimacy to a
wide range of water-centric CE applications, including water reuse, nutrients and
energy recovery in Europe, and understand the legitimacy of CE applications
through perceptions. This study was underpinned by a tailored framework
including four legitimacy categories: moral, cognitive, pragmatic, and regulatory.
A qualitative and case study research design was employed, involving interviews
with case study stakeholders (n = 44) and the public (n = 12). A thematic analysis
using mainly a deductive logic was employed to associate interviewees’
perceptions with legitimacy categories. This thesis provided evidence of
stakeholders’ perceptions towards contemporary case studies embedding CE
applications in Sweden, the Netherlands, and the UK, as well as public
perceptions of hypothetical CE applications in the UK.
For stakeholders and the public, findings described perceptions associated with
the four legitimacy categories and thus showed the meaning of legitimacy
associated with CE applications. For each case study and legitimacy category,
interviewees portrayed a common basis of legitimacy and contextual specificities
that included differences in the number of times a specific legitimacy sub-
category was referred to in the interviews. Overall, perceptions placed high
importance on legitimacy associated with social and environmental norms, and
self-interested benefits, comprehensibility, and taken-for-granted routines whilst
depicting low legitimacy associated with outreach and involvement practices as
well as with regulations. Finally, the main linkages between legitimacy categories
were reported.
This research makes two contributions. Firstly, it contributes to the CE literature
by providing a complementary view to an acceptance perspective and showing a
non-binary, in-depth, and nuanced view of institutional, social, and cultural
factors. Secondly, a theoretical contribution was made that extends the
interpretation of legitimacy in a CE context, and challenges existing knowledge
on legitimacy by providing a non-linear, context-dependent, and complex view on
legitimation processes. Finally, practical recommendations were formulated for
outreach managers, regulators, the government, and prospective companies.
These are based on using the legitimacy framework as a diagnostic tool to build
specific legitimacy categories.PhD in Water, including Desig
Unlocking AI's potential in the food supply chain: a novel approach to overcoming barriers
Get PDFThis paper delves into the challenges impeding the seamless integration of artificial intelligence (AI) within the food supply chain (FSC) and introduces a novel methodological framework that combines the NK Model with the Decision-Making Trial and Evaluation Laboratory (DEMATEL) technique. Through an exhaustive literature analysis and expert discussions, the research identifies and categorizes significant obstacles to AI deployment in the FSC. These hurdles include the imperative for a skilled labor force, financial limits, regulatory complexity and technological limitations. The unique DEMATEL-NK approach highlights the interconnected nature of these barriers, pinpointing the most critical impediments. The study's implications extend to the broader domains of AI adoption in agriculture and the food industry, offering a nuanced perspective for policymakers, industry stakeholders, and researchers. The findings underscore the imperative of overcoming these barriers for the successful implementation of AI technologies in the FSC, promising advancements in efficiency, quality, and sustainability. The innovative methodology not only sheds light on the interconnectedness of these barriers but also provides a systematic approach for prioritizing and implementing solutions. This research offers a fresh viewpoint on barrier relationships, guiding decision-makers in crafting effective strategies and interventions to propel AI integration in the FSC forward.Journal of Agriculture and Food Researc
Assessment of flyby methods as applied to close encounters among asteroids
Get PDFOrbital flybys have been extensively studied for spacecraft missions, resulting in effective mathematical and physical models. However, these models’ applicability to natural encounters involving asteroids has not been explored. This paper examines the applicability of two such theories, patched conics (PC) and the Keplerian map (KM), to asteroid encounters. A review of the two methods will be provided, highlighting their assumptions and range of applicability. Simulations of asteroid–asteroid encounters will then be performed to evaluate their effectiveness in these scenarios. The simulation parameters are set by collecting data on actual asteroid–asteroid encounters, hereby presented, generally characterised by high close approach distances and small masses of the perturbing bodies, if compared to those used to build the flyby theories. Results show that the PC theory’s effectiveness diminishes with increasing approach distances, aligning with its assumptions. Moreover, the prediction of the model is better in the geometric configurations where the flyby has major effects on the orbital energy change. The KM theory has shown good effectiveness for encounters occurring outside the sphere of influence of the perturbing body, even for very high distances. This research investigates flyby models’ strengths and weaknesses in asteroid encounters, offering practical insights and future directions.European Space Agency (ESA) Open Space Innovation Platform (OSIP) campaign and by Cranfield University (ESA Contract no. 4000134762/21/NL/MH/hm-Asteroid Collisions).Aerospac
Human facial emotion recognition for adaptive human robot collaboration in manufacturing
Get PDFThe integration of robots into various industries, including manufacturing, has introduced new challenges in achieving efficient human-robot collaboration. A crucial aspect of successful collaboration is the ability of robots to understand and respond to human emotions. In the context of human-robot collaboration in manufacturing, accurately predicting human emotions is essential for enhancing efficiency and safety. This paper presents a setup for human emotion detection, focusing on facial emotion recognition. The proposed model and descriptive summary involve the utilising state-of-the-art algorithms such as AlexNet, HaarCascade (HCC), MTCNN (Multi-Task Cascaded Convolutional Neural Networks), and SVM (Support Vector Machine), applied to datasets like CK+, JAFFE, and AffectNet. The performance of each facial recognition model is evaluated in real-time scenarios, resulting in significant progress with an accuracy improvement from 40% to 78.1%. These results demonstrate the effectiveness of the approach in enabling adaptive robot control based on human emotions and enhancing collaboration quality. This research uniquely integrates facial emotion recognition and robot control to enable adaptive responses during human-robot collaboration in manufacturing settings. By understanding and responding to human emotions, robots can improve their interactions with humans, leading to increased productivity and improved overall collaboration efficiency.This work was supported by EPSRC-funded Made Smarter Innovation - Re-search Centre for Smart, Collaborative Industrial Robotics project (EP/V062158/1).25th Annual Conference Towards Autonomous Robotic Systems (TAROS
Multidisciplinary design and manufacturing of a Tesla pump prototype
Get PDFTo widen the range of hydraulic efficiencies of boundary layer pumps, a full design methodology has been proposed in order to identify critical issues for their performance and manufacturing. The methodology integrated a 2D numerical code, CFD and FEM analyses, coupled with manufacturing assessments as feedback mechanism. Considering budget constraints and in-house machining capabilities, a quick first prototype was produced. Analyses of the design are pointing out that the volute design initially chosen will not help to achieve an increase in the overall efficiency. The curves of head achieved with 2D and CFD are in agreement, but the latter determines the losses with larger accuracy, thus achieving lower values of head. The 2D model shows limits in the determination of the efficiency, effectively corrected by the CFD analysis. Critical parameters as disc thickness and gap between discs will require a more sophisticated assembly process and materials outsource. The proposed methodology could be used as a reference for the design and performance evaluation of this kind of turbomachinery in the future. The procedure lead to a prototype design, whose optimal efficiency slightly lower than 30 % was achieved at 5000 rpm with 0.3 mm disks gap.Applied Thermal Engineerin
Investigation of an Atmospheric Pressure Plasma device for reduction of water use in sustainable cleaning of concentrating solar power mirrors
Get PDFSansom, Chris - Associate SupervisorConcentrating Solar Power (CSP) is a method of renewable electricity generation
that uses large areas of mirrors, that reflect and focus the sun’s energy onto a
receiver which is then used to heat water to power a conventional steam turbine,
generating electricity.
These plants are typically located in areas with consistently high levels of sunlight
which are typically arid desert areas where sand and dust is deposited onto the
mirrors, reducing their reflectivity and thus the plant’s output. Conventional mirror
washing consumes huge quantities of water, which is costly and incurs ethical
and environmental concerns in areas already experiencing water scarcity.
This work investigates the use of an atmospheric pressure plasma to induce a
super-hydrophilic surface on the soiled mirrors which are then able to be cleaned
with significantly lower quantities of water. Characterisation of the plasma torch
is conducted, and surface energy modification effects investigated with regards
to water spreading, evaporation, and travel. For cleaning trials, solar type mirrors
were artificially soiled with sand gathered from a CSP plant, then plasma
processed before being conventionally washed with water. Mirrors that were
subject to soiling were successfully washed, as determined by reflectance
measurements, with up to 87.5% less water than mirrors exposed to the same
artificial soiling procedure but without plasma processing prior to washing.
Plasma processed samples also exhibited self-cleaning properties when subject
to condensation trials, mimicking overnight dew formation. There was no
observed effect in either reduction or exacerbation of subsequent resoiling of
plasma processed samples.
Fundamental processes behind these effects are discussed and the application
and implication of the work are considered.Engineering and Physical Sciences Research Council (EPSRC)PhD in Manufacturin
Motion response and energy harvesting of multi-module floating photovoltaics in seas
Get PDFFloating Photovoltaic (FPV) systems are emerging as a new type of ocean renewable energy, offering advantages such as avoiding land use and promoting power generation efficiency. Providing significant cost-effectiveness for manufacturing, transportation, and installation, FPV systems with modular floating platforms exhibit the potential to replace the conventional large steel-frame one. However, the performance of such multi-floating body structures under wave conditions remain underexplored. In this paper, based on potential flow theory, the motion characteristics and power performance of the proposed FPV array connected by the articulated system are evaluated. The results indicate that the FPV arrays with shorter floating structures exhibit greater pitch motion, especially when the wave condition matches the pitch resonance. For multi-float cases, the articulated system, optimized with appropriate parameters, demonstrates efficacy as attenuators. Additionally, the proposed FPV array has great potential to serve as an infrastructure for integrating solar and wave energy. For a selected offshore site, potential wave energy output from motion attenuators between FPV floaters is assessed together with solar energy output. Overall, this study serves as a valuable reference for the design and optimization of the multi-modules FPV and advances the research on combined solar and wave energy utilization on floating structures.This work is supported by the National Natural Science Foundation of China National Outstanding Youth Science Fund Project (52222109), the National Natural Science Foundation of China (52071096 and 52201322), Project of State Key Laboratory of Subtropical Building and Urban Science (2023ZB14), Guangdong Basic and Applied Basic Research Foundation (2022B1515020036 and 2023A1515012144).Ocean Engineerin
Health monitoring of cavitation erosion on airframe fuel pumps
Get PDFJudt, David - Associate SupervisorAircraft maintenance is a critical aspect of operations that can lead to substantial
financial savings if improved. The fuel pump is a vital component of the entire
aircraft, ensuring fuel delivery to the engine. Cavitation is common in these
pumps, leading to erosion and reducing the pump's remaining useful life.
Therefore, the main objective of this work is to develop a viable health monitoring
method to diagnose cavitation erosion, where few solutions exist. Initially, a
literature review is conducted to identify knowledge gaps and opportunities for
technology transfer related to current Health Monitoring (HM) technologies for
airborne pumps. Four sensing methods, pressure, flow, current, and temperature
sensing, are shortlisted based on their past applications and suitability for an
aircraft fuel system installation. A hybrid health monitoring scheme consists of a
Computational Fluid Dynamics (CFD) simulation, a model running on Simscape,
and an experimental test rig. Live experiments are conducted to validate the
simulation methods, enabling the testing of scenarios on a wide range of
boundary conditions. The simulations demonstrate strong alignment with the
experimental data and successfully distinguish the different levels of erosion.
Three out of the four tested sensing methods are sensitive enough to distinguish
the different levels of erosion, but each method has its advantages and
limitations. Temperature sensing is not useful for health monitoring as the
ambient environment strongly influences its results. Despite the success of the
developed health monitoring schemes, there is a need for further research and
development into more sophisticated health monitoring algorithms before the
technologies can be widely implemented on aircraft.Engineering and Physical Sciences Research Council (EPSRC)EngD in Sustainable Materials and Manufacturin