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Novel ecosystems: the new normal?
No full textAs humans continue to radically alter the environment, new species assemblages are emerging – combinations of organisms that have never been observed before. What does this changing world mean for ecology?The Nich
Transformation of the product lifecycle value chain towards industry 5.0
Get PDFThe transition from Industry 4.0 to Industry 5.0 has broadened the focus of enterprises, moving beyond their organisational boundaries limits to embrace the interconnected structure within the product lifecycle value chain. Despite this shift, there remains a significant gap in research on the framework for transforming the product lifecycle value chain from Industry 4.0 to Industry 5.0. Thus, building upon the achievements of Industry 4.0, the proposed value chain transformation frameworks are proposed, which can improve sustainability and resilience while considering human needs. The frameworks offer enterprises a comprehensive understanding of the structure and strategic approach required for the Industry 5.0 product lifecycle value chain transformation. Finally, the authors summarise six research challenges and opportunities and eleven research questions to advance the transformation of the Industry 5.0 product lifecycle value chain.6th IFAC Workshop on Advanced Maintenance Engineering, Services and Technology AMEST 2024IFAC-PapersOnLin
Strategic flood impact mitigation in developing countries’ urban road networks: application to Hanoi
Get PDFDue to climate change, the frequency and scale of flood events worldwide are increasing dramatically. Flood impacts are especially acute in developing countries, where they often revert years of progress in sustainable development and poverty reduction. This paper introduces an optimization-based decision support tool for selecting cost-efficient flood mitigation investments in developing countries’ urban areas. The core of the tool is a scenario-based, multi-period, bi-objective Mixed Integer Linear Programming model which minimizes infrastructure damage and traffic congestion in urban road networks. The tool was developed in collaboration with Vietnamese stakeholders (e.g., local communities and government authorities), and integrates data and inputs from other disciplines, including social science, transport economics, climatology and hydrology. A metaheuristic, combining a Greedy Randomized Adaptive Search Procedure with a Variable Neighborhood Descent algorithm, is developed to solve large scale problem instances. An extensive computational campaign on randomly generated instances demonstrates the efficiency of the metaheuristic in solving realistic problems with hundreds of interdependent flood mitigation interventions. Finally, the applicability of the interdisciplinary approach is demonstrated on a real case study to generate a 20-year plan of mitigation investments for the urban area of Hanoi. Policy implications and impacts of the study are also discussed.British Academy’s Cities and Infrastructure Programme (Ref: CI170099) and of the Engineering and Physical Sciences Research Council, United Kingdom (Ref: EP/T004002/1).European Journal of Operational Researc
Consensus-based deep reinforcement learning for mobile robot mapless navigation
Get PDFWhen using mobile robots to perform data collection about the surroundings, the performance might be dissatisfying since the environments could be unknown and challenging. This situation will pose challenges for mobile robot navigation and exploration. To tackle this issue, we propose a consensus-based deep reinforcement learning (DRL) algorithm for multiple robots to perform mapless navigation and exploration. The proposed algorithm leverages both consensus-based training and DRL, which reduces required training steps while maintaining the same training reward. Once trained with fixed obstacles, the proposed training model can demonstrate adaptability in handling real-world random static obstacles and sudden obstacles. The experimental video is available at: at: https://youtu.be/ym2yvbKg4fU.This work is supported by UKAEA/EPSRC Fusion Grant 2022/2027 No. EP/W006839/1.2024 IEEE International Conference on Industrial Technology (ICIT
Modeling of dual‐factor drag correction model for bubbly flow under elevated pressure
No full textSpecial Issue: 8th International Conference on Fuel Cell & Hydrogen Technology – 3rd Symposium on Fuel Cell and Hydrogen Technology 2023 (ICFCHT-SFCHT 2023)A pressure correction method is proposed considering the influence of a dual factor. The applicability of a pressure correction method coupled with a drag model is discussed along with the accuracy of the simulation results obtained by such a pressure correction method. It is found that the present pressure correction method combined with the DBS (dual bubble size) drag model can accurately reflect the changing trend of gas holdup distribution with pressure. It is also established that results from this model applied to a bubble column match well with the experimental data. Finally, when compared with other pressure correction models, the proposed model shows better robustness in three‐dimensional simulations and can predict radial gas holdup distributions with better accuracy.China Scholarship Council, Jiangsu Provincial Department of Education, National Natural Science Foundation of ChinaChemical Engineering & Technolog
Robust sliding mode controller design for orbital payload deploying spacecraft
Get PDFThis work demonstrates the feasibility of usage of a sliding mode controller in the case of orbital payload deployers. The proposed control law suggested herein allows for disturbance rejection during the payload deployment phase, as well as provide a basis for angular rate tracking purposes. The stability of the control law is determined by Lyapunov theory, and realistic spacecraft simulations have been created to verify the robustness in the presence of disturbances as well as the general tracking capabilities.2024 CEAS EuroGNC conferenc
DATASET "De-icer Mobilisation by Rainfall"
No full textHPLC data of propylene glycol in runoff (mobilised de-icer in rainfall)Natural Environment Research Council (NERC
Biodegradation of oily waste sludge using vermiremediation and composting process bioaugmentated with isolated hydrocarbon-degrading bacteria: performance and ecotoxicity assessment
No full textDegradation of petroleum hydrocarbons (PHs) contents of oily waste sludge (OWS) is necessary in order to prevent the related environmental pollution. The present study aimed to investigate the degradation of total petroleum hydrocarbons (TPHs) from OWS using bioaugmentated composting (BC) with hydrocarbon-degrading bacterial consortium (HDBC) as pre-treatment followed by vermicomposting (VC) by Eisenia fetida. After isolating two indigenous bacterial strains from OWS, the ability of their consortium in degradation of crude oil was tested in Bushnell-Haas medium (BHM). Then, biodegradation of OWS was measured in the VC alone, BC alone, simultaneous BC and VC (BCVC), and BC followed by VC (BCFVC) containing high levels (30 g/kg) of TPHs. Toxicity tests including the mortality of mature earthworms and the numbers of juveniles were conducted at the TPHs of 0–40 g/kg. The obtained results indicated that the HDBC removed 18–64 % of TPHs of crude oil (1–5 %) in BHM after 7 days of incubation. After a period of 12 weeks, the removal rates of TPHs in the VC, BC, BCVC, and BCFVC experiments were 23.7, 79.5, 85.2, and 91.8 %, respectively, verifying the efficacy of simultaneous application of HDBC and worms in bioremediation of OWS. The TPHs contents of OWS exhibited toxic effects on E. fetida at some concentrations and the median lethal concentration (LC50) of TPHs was computed to be 14.5 g/kg after 28 days. This study demonstrated the effectiveness of composting bioaugmentated with HDBC as a pre-treatment step followed by vermicomposting in bioremediation of OWS.Authors are thankful to Arak University of Medical Sciences for funding and supporting this research [Grant Number 3099].Environmental Nanotechnology, Monitoring & Managemen
Landing gear health assessment: synergising flight data analysis with theoretical prognostics in a hybrid assessment approach
Get PDFThis study addresses a critical shortfall in aircraft landing gear (LG) maintenance: the challenge of detecting degradation that necessitates intervention between scheduled maintenance intervals, particularly in the absence of hard landings. To address this issue, we introduce a Performance Degradation Metric (PDM) utilising Flight Data Recorder (FDR) output during the touchdown and initial roll phases of landing. This metric correlates time-series accelerometer data from a Saab 340B aircraft’s onboard sensors with non-linear response dynamic models that predict expected LG travel and reaction profiles across a set of ground contact cycles within a single landing. This facilitates the early detection of deviations from standard LG response behaviour, pinpointing potential performance abnormalities. The initiator of this approach is the Landing Sequence Typology, which systematically decomposes each aircraft landing into successive dynamic periods defined by their representative boundary conditions. What follows is the setting of initial parameters for the ordinary differential equations (ODE)s of motion that determine the orientation and impact responses of the most critical components of the LG assembly. Solving these ODEs with the integration of a non-linear representation of an oleo-pneumatic shock absorber model compliant with CS25 aircraft standards produces anticipated profiles of LG travel based on factors such as aircraft weight and speed at touchdown, which are subsequently cross-referenced with real accelerometer data, enhanced by video footage analysis. This footage is crucial for verifying the sequence of LG touchdowns and corresponding accelerometer outputs, thereby bolstering the precision of our analysis. Upon the conclusion of this study, by facilitating the early identification of LG performance deviations in specific landing scenarios, this diagnostic tool shall enable timely maintenance interventions. This proactive approach not only mitigates the risk of damage escalation to other components but also transitions main LG maintenance practices from reactive to proactive.PHM Society European Conference 202
Dataset for - Environmental Fate of 2,4,6-trinitrotoluene (TNT) in Marine Environments - Dissolution and Remediation Strategies
No full textThis study demonstrates that the dissolution behaviour of TNT in seawater compared to distilled water differs, where TNT dissolved slower in the presence of salts compared to freshwater systems. The slower dissolution rate observed in seawater suggests that TNT may persist longer in marine environments, albeit with a heightened risk of generating degradation products that could pose secondary environmental challenges over time. Furthermore, our investigation into ACs and biochar for adsorption-based remediation revealed NORIT 1240 and ground rice husk as highly effective materials, capable of reducing TNT concentrations by more than 90% in both distilled and seawater scenarios. Ground rice husk, in particular, emerges as a sustainable alternative to conventional ACs, highlighting its potential for future applications in marine environmental clean-up efforts. These findings not only contribute to our understanding of how TNT interacts with different water matrices but also offer practical insights into effective remediation strategies. Moving forward, continued research into the behaviour of TNT in complex marine environments and the development of sustainable remediation technologies will be crucial for mitigating the long-term impacts of munition residues on marine ecosystems