20505 research outputs found
Sort by
Design, development, and evaluation of a contactless respiration rate measurement device utilizing a self-heating thermistor
Get PDFThe respiration rate (RR) is an important vital sign for early detection of health deterioration in critically unwell patients. Its current measurement has limitations, relying on visual counting of chest movements. The design of a new RR measurement device utilizing a self-heating thermistor is described. The thermistor is integrated into a hand-held air chamber with a funnel attachment to sensitively detect respiratory airflow. The exhaled respiratory airflow reduces the temperature of the thermistor that is kept at a preset temperature, and its temperature recovers during inhalation. A microcontroller provides signal processing, while its display screen shows the respiratory signal and RR. The device was evaluated on 27 healthy adult volunteers, with a mean age of 32.8 years (standard deviation of 8.6 years). The RR measurements from the device were compared with the visual counting of chest movements, and the contact method of inductance plethysmography that was implemented using a commercial device (SOMNOtouch™ RESP). Statistical analysis, e.g., correlations were performed. The RR measurements from the new device and SOMNOtouch™ RESP, averaged across the 27 participants, were 14.6 breaths per minute (bpm) and 14.0 bpm, respectively. The device has a robust operation, is easy to use, and provides an objective measure of the RR in a noncontact manner.This research was funded by the National Institute of Health Research (NIHR), United Kingdom, scheme Invention for Innovation (i4i), Reference: II-LB-0712-20004.Technologie
Monitoring framework for physical knowledge exploration in wire-based directed energy additive manufacturing (w-DEDAM)
Get PDFMonitoring in wire-based directed energy deposition additive manufacturing (w-DEDAM) is crucial for ensuring part quality and process stability. It aids in optimising process control, enhancing efficiency, and minimising material waste. Additionally, monitoring provides valuable documentation for regulatory compliance and supports maintenance by tracking equipment performance. Effective monitoring and relevant control enhance process reliability, reduce scrap, and ensure the production of high-quality components. However, current monitoring systems in w-DEDAM face significant challenges. Key issues include a lack of standardisation in monitored variables, leading to inconsistent data and interpretation. Many existing monitoring systems often focus on the adjustable “knob” variable measurements rather than critical factors that more accurately represent physical process conditions. This narrow focus can fail to capture essential aspects of process explanation and part quality. Furthermore, there is a deficiency in integrating monitoring data with digital modelling and qualification methods, limiting the ability to use real-time data for comprehensive process optimisation and predictive analysis. Addressing these gaps is crucial for advancing system effectiveness. In this research, key process variables will be defined and explained to enhance process understanding. A knowledge-driven monitoring framework will be proposed to tackle the issues of standardisation and relevance of monitored parameters, ensuring that critical variables are accurately captured and utilised. Additionally, the study will introduce a commercial industry monitoring software based on this framework, which is currently used in the industry. This software integrates the proposed approach, offering a robust solution for real-time monitoring and process control, thus addressing existing limitations and supporting improved process optimisation and digital modelling.Engineering and Physical Sciences Research Council58th CIRP Conference on Manufacturing Systems 2025Procedia CIR
Phase-Based Motion Magnification in outdoor conditions: Robustness and Natural Frequency extraction
Get PDFZanotti Fragonara, Luca - Associate SupervisorIn this study, Phase-Based Motion Magnification is combined with 2D Point Tracking
to enhance data extraction under noisy outdoor conditions. The aim is to investigate
whether the use of Phase Based Motion Magnification along with 2D PT can increase
accuracy of frequencies extracted in robust conditions. The study presents three
experiments: a fixed wing on a shaker machine, a light pole and a building.
Frequencies are extracted in all three experiments and compared against previous
research and finite element analysis. Finally, the study touches on ways to automate
the suggested procedure.MSc by Research in Aerospac
Dual-wavelength laser speckle technique for absolute angle sensing In two dimensions
Get PDFThis thesis presents the theory, development, and construction of a novel absolute
angle sensor employing dual-wavelength laser speckle for use in measuring two dimensional
surface tilt angles. The targeted application is robotic manufacturing,
specifically robot drilling where perpendicularity to the workpiece is particularly
important and an accuracy of up to 0.1° is desired. The proposed technique uses
two collinear beams of differing wavelengths, illuminating the surface of interest.
The generated speckle patterns are shifted with respect to each other, with the
position and orientation of the shift being directly related to the two dimensional
tilt of the surface. This relationship is derived mathematically, and a number of
experimental results are presented to confirm its validity.
Two full implementations of the sensor were tested and characterised. The first
used a single laser outputting two longitudinal modes with a wavelength separation
of 0.5nm. Initial results in one dimension presented measurements over the wide
angle range of ±45.00°, with an average absolute bias error of around 0.51°. These
errors were smaller at smaller magnitudes, averaging around 0.22° between ±11.2°.
Further experiments in two dimensions focused on the magnitude range ±7.50°,
finding average absolute bias errors of 0.15° in θx and 0.08° in θy. The estimated
standard deviations in these measurements were 0.10° in θx and 0.18° in θy.
The second sensor used two separate lasers with a wavelength separation of 21.5nm,
increasing the sensitivity by a factor of 40. This sensor showed greater wavelength
instability due to the two independent lasers and an increased mode instability. As
such, the overall errors in experimental results were greater than expected, and the
data were filtered to demonstrate the achievable performance if this laser instability
were resolved. Results for surface tilts up to ±0.25° in two dimensions showed
average absolute bias errors of 0.007° in θx and 0.009° in θy after filtering, and
standard deviations of 0.003° in θx and 0.017° in θy. These results demonstrate that
the dual-wavelength speckle technique has the potential to provide high accuracy
absolute angle measurements in two dimensions.PhD in Transport System
Evaluation of failings in urban water supply and sanitation systems in Sub-Saharan Africa: a systematic review to inform future planning
Get PDFThe high failure rate of water supply and sanitation (WSS) systems is a major concern, especially for developing countries. Using the Collaboration for Environmental Evidence guidelines, this study carried out a systematic review of literature on failings in WSS in the urban areas of Sub-Saharan Africa to identify the factors hindering sustainability as lasting coverage. There were 101 full-text articles examined and 21 articles included in the final review. The findings are discussed through the lens of the financial, institutional, environmental, technological and social (FIETS) framework and depicted in a causal loop diagram to visualize the system structure. In total, 37 factors that contribute to the failings of urban WSS systems across 14 Sub-Saharan African countries were identified. The root causes of failed or failing systems included a lack of stakeholder engagement in the planning and implementation; limited human resources capacity; limitations imposed by settlement type (informal settlements); insufficient funds, corruption and mismanagement of funds; and insufficient operation and maintenance of facilities. The study concludes that sustainability in the sector will involve the use of legal instruments, adequate planning techniques, anti-corruption and cost recovery mechanisms to ensure long-term financing.Journal of Water, Sanitation and Hygiene for Developmen
A comprehensive review and future challenges of energy-aware path planning for small unmanned aerial vehicles with hydrogen-powered hybrid propulsion
Get PDFUnmanned aerial vehicles (UAVs) with fully electric propulsion systems mainly use lithium-based batteries. However, using fuel cells, hybrid propulsion systems are created to improve the flight time and payload capacity of the UAVs. Energy management and energy-aware path planning are important aspects to be explored in hybrid-propulsion powered UAV configurations. These facilitate optimal power distribution among energy sources and motion planning considering energy consumption, respectively. In the literature, although there are many studies on the energy management of hybrid-powered UAVs and path planning of only battery-powered UAVs, there are research gaps in energy-aware path planning of hybrid-powered UAVs. Additionally, the energy management of hybrid-powered UAVs is usually considered independent of path planning in the literature. This paper thoroughly reviews recent energy-aware path planning for small UAVs to address the listed critical challenges above, providing a new perspective and recommendations for further research. Firstly, this study evaluates the recent status of path planning, hydrogen-based UAVs, and energy management algorithms and identifies some challenges. Later, the applications of hydrogen-powered UAVs are summarised. In addition, hydrogen-based hybrid power system topologies are defined for small UAVs. Then, the path-planning algorithms are classified, and existing studies are discussed. Finally, this paper provides a comprehensive and critical assessment of the status of energy-aware path planning of UAVs, as well as detailed future work recommendations for researchers.The first author would like to acknowledge support from the Scientific and Technological Research Council of Türkiye (TÜBITAK) for funding his research visit scheme to Cranfield University for the project work (Appl. no.: 1059B192301276; REF: 53325897-115.02-476393).The Aeronautical Journa
Towards evidence‐based biodiversity assessment tools for agroforestry systems
No full textAll data are archived via Figshare along with the R code and are publicly available: https://figshare.com/s/e51c87dd073dbb02faf5, DOI:10.6084/m9.figshare.24776298Agroforestry can help to conserve biodiversity and enhance multiple ecosystem services such as carbon sequestration, microclimate regulation and nutrient cycling. However, in land planning and biodiversity certification schemes it remains difficult to quantify the effect of agroforestry on biodiversity across time and space.
Here we combine insights from a second‐order meta‐analysis, a stakeholder questionnaire, and a review of biodiversity assessment tools to establish a route towards more accurate estimates of agroforestry effects on biodiversity. Via a synthesis of cross‐taxa meta‐analyses, we evaluated the impact of agroforestry and landscape structure on biodiversity. Complementing the literature evidence, we performed a stakeholder questionnaire to determine the perceptions and preferences of stakeholders with regards to biodiversity.
The meta‐analyses synthesis indicates predominantly positive or no effects of agroforestry practices on biodiversity, albeit with contextual nuances such as landscape structure and system design. The questionnaire revealed stakeholders' recognition of biodiversity's pivotal role in agroecosystems and a willingness to support methods to assess the effects of agroforestry on biodiversity. There was a preference for user‐friendly, web‐based tools that integrated mapping features and checklists tailored to diverse agroforestry types. Finally, we evaluated 73 existing biodiversity tools in terms of their capability of incorporating agroforestry components. The tools' review revealed limitations in terms of their specificity, accessibility or capacity to encompass multifaceted agroforestry designs.
Practical implication. Our three‐faceted approach provided comprehensive insights about the building blocks required to develop an evidence‐based and user‐friendly tool for predicting the effects of agroforestry on biodiversity. Specifically, our interdisciplinary synthesis underscores the potential of agroforestry in promoting biodiversity while emphasizing the need for an evidence‐based, user‐centric tool to effectively assess biodiversity within agroforestry systems, accounting for landscape context and system design. Such a tool should be constructed with input data for different agroforestry types, across taxa and updateable when knowledge gaps are filled.HORIZON EUROPE Food, Bioeconomy, Natural Resources, Agriculture and Environment; 101059794This work was supported by the DigitAF project (grant agreement no. 101059794), co-funded by the European Commission, European Research Agency, within the Horizon Europe programme.Ecological Solutions and Evidenc
A Stackelberg-Nash game framework for overcoming remanufacturing barriers in a duopoly
No full textIn duopoly markets, less-preferred brands with lower customer acceptance often hesitate to adopt environmentally beneficial remanufacturing due to profitability concerns, especially when decisions involve the entire supply chain. This study proposes a Stackelberg–Nash game framework to explore optimal remanufacturing and pricing strategies for two competing supply chains, each comprising a manufacturer and an exclusive retailer. The model analyses both external competition between brands and internal competition between new and remanufactured products, considering customer acceptance levels and the availability of used products suitable for remanufacturing. Analytical results show that when manufacturing costs are low, remanufacturing increases the profit of the less-preferred brand without affecting the more-preferred one. When costs are high and the less-preferred brand is supported by its retailer, numerical results indicate that remanufacturing can still enhance profitability, with up to 24% higher profit compared to the no-remanufacturing case. However, when costs are prohibitively high, remanufacturing is unlikely to be viable without external incentives. Sensitivity analysis shows that increasing the customer acceptance level of the less-preferred brand typically reduces the more-preferred brand's profit and increases the less-preferred brand's profit, except when acceptance exceeds 80% under low-cost conditions, where intensified competition reduces the latter's profitability. Under high-cost conditions, increasing acceptance from 70% to 90% may lead to a 56% reduction in the more-preferred brand's profit and a 44% increase in the less-preferred brand's profit. The level of acceptance for remanufactured products also affects profitability differently across cost structures and strategic conditions, revealing that internal product competition shifts substantially depending on market and operational parameters.Journal of Dynamics and Game
Towards a future battlefield forensics framework: a NATO action research case study
No full textThe data that support the finding of this study are available on request from the corresponding author (RMR). Some data are not publicly available due to restrictions – for example, where they contain information that could compromise the privacy of research participants and/or consist of NATO or national classified documents.This article examines the key challenges and requirements for achieving interoperability in NATO battlefield forensics – the application of scientific methods to collect, analyse, and disseminate information, intelligence and evidence in conflict zones, bridging military and civilian domains. The article presents findings from three empirical inputs: a scoping mission and doctrinal review, NATO exercises and experimentation, and stakeholder engagement through surveys, workshops, and conferences. Five cross-cutting themes were identified: conceptual ambiguity; capability shortfalls; fragmented legal frameworks; weak interagency cooperation; and shared future needs. The analysis demonstrates that interoperability in NATO battlefield forensics is constrained not only by technical gaps but also by doctrinal, legal, organisational and cultural barriers. The article concludes that progress depends on three priorities: institutionalising a staffed Technical Exploitation (TE) function and fit-for-purpose doctrine; harmonising legal frameworks for operational and judicial use; and building predicable civil-military pathways and competence. It also highlights the need to overcome cultural barriers, notably the legacy perception of TE as a narrow counter-IED tool and the tendency to exercise blindness: the assumption that exploitation processes will function automatically in crises.This work was supported by the NATO Defence Against Terrorism Programme of Work (DAT POW), Cranfield University and Danish Defence.Scandinavian Journal of Military Studie
Phage therapy for environmental biotechnology applications
No full textEnvironmental compartments, from soils and crop rhizospheres, to bio-reactors and municipal water networks have emerged as dynamic hot-spots for antimicrobial-resistance evolution and dissemination. Bacteriophages offer a precision, self-amplifying alternative to conventional biocides, yet their environmental deployment, intellectual-property space and commercial readiness remain only partially charted. Here, we critically synthesize the past decade of progress in phage-based interventions across three sectors: (i) soil remediation and crop-protection interfaces, where multi-phage cocktails suppress wilt- and blight-causing pathogens while preserving beneficial microbiota; (ii) biofuel and petro-energy infrastructures, in which lytic phages mitigate the microbiologically influenced corrosion and contaminated fermentations, restoring ethanol yields; and (iii) natural and engineered water systems, where phages show promise in treating recalcitrant biofilms, algal blooms and selectively ablate World Health Organization-priority pathogens. Meta-analysis of the World Intellectual Property Organization database reveals rapidly rising but geographically skewed patent activity, with China and the United States accounting for >61% of reviewed filings, and a gap between laboratory proof-of-concepts and marketed products. We identify bottlenecks, including lack of good manufacturing practice at scale, fragmented regulatory frameworks, and the evolutionary balance between single-phage precision and cocktail breadth. A roadmap is suggested that couples high-throughput phage discovery, synthetic tailoring and adaptive approval pathways. Together, these advances position environmental phage therapy to become a cornerstone of the One-Health response to increasing levels of microbial resistance.All authors acknowledge funding from UK Water Industry Research Limited. FH acknowledges support from the UK Research and Innovation (UKRI) Biological Sciences Research Council (BBSRC) grant BB/Y008332/1Frontiers in Microbiolog