17628 research outputs found
Sort by
Event-Triggered Relearning Modeling Method for Stochastic System with Non-Stationary Variable Operating Conditions
Get PDFThis study presents a novel event-triggered relearning framework for neural network modeling, designed to improve prediction precision in dynamic stochastic complex industrial systems under non-stationary and variable conditions. Firstly, a sliding window algorithm combined with entropy is applied to divide the input and output datasets across different operational conditions, establishing clear data boundaries. Following this, the prediction errors derived from the neural network under different operational states are harnessed to define a set of event-triggered relearning criteria. Once these conditions are triggered, the relevant dataset is used to recalibrate the model to the specific operational condition and predict the data under this operating condition. When the predicted data fall within the training input range of a pre-trained model, we switch to that model for immediate prediction. Compared with the conventional BP neural network model and random vector functional-link network, the proposed model can produce a better estimation accuracy and reduce computation costs. Finally, the effectiveness of our proposed method is validated through numerical simulation tests using nonlinear Hammerstein models with Gaussian noise, reflecting complex stochastic industrial processes
Brutna beten [Fantomen 5/2024]
No full textThe Phantom intervenes when poachers kill one elephant and wound another, causing the animal to run amok. This 22-page story written by David Bishop was illustrated by Anthony Spay and Brian Atkins
Can proactive support prevent unscheduled care? A controlled observational retrospective cohort study in cancer patients in Scotland
Get PDFIntroduction: Preventative spend is a global health and social care strategy. Improving Cancer Journeys (ICJ) is a proactive, holistic, multidisciplinary project consistent with this agenda, currently being rolled out across Scotland and parts of UK. ICJ helps people with cancer access whatever support they need to mitigate their most pressing concerns. This study hypothesised that ICJ service users should subsequently use less unscheduled care than matched cohorts not using ICJ. Methods: Retrospective observational cohort study using linked national datasets. N = 1,214 ICJ users in Glasgow were matched for age, sex, deprivation, cancer type, stage, and diagnosis year to two control groups: 1. Cancer patients from Glasgow before ICJ (pre-2014), 2. Cancer patients from rest of Scotland during study period (2014–2018). Cancer registrations were linked for 12-month baseline and study periods to: NHS24 calls, A&E admissions, inpatient hospital admissions, unscheduled care, number & cost of psychotropic prescriptions. Per-person mean service uses were compared between groups. Results: There was a significant increase in NHS24 calls in the ICJ group (0.36 per person vs. -0.03 or 0.35), more and longer A&E attendances in ICJ (0.37 per person vs. 0.19 or 0.26; 2.19 h per person vs. 0.81–0.92 h), more and longer hospital admissions in ICJ (4.25 vs. 2.59 or 2.53; 12.05 days vs. 8.37 or 8.64), more care pathways involving more steps in ICJ (0.77 spells vs. 0.39 or 0.57; 1.88 steps vs. 1.56 or 1.21), more psychotropic drug prescriptions and higher costs in ICJ (1.88 prescription vs. 1.56 or 1.21; £9.51 vs. £9.57 or £6.95) in comparison to both control groups. Discussion: ICJ users sourced significantly more unscheduled care than matched cohorts. These findings were consistent with much of the comparable literature examining the impact of non-health interventions on subsequent health spend. They also add to the growing evidence showing that ICJ reached its intended target, those with the greatest need. Together these findings raise the possibility that those choosing to use ICJ may also be self-identifying as a cohort of people more likely to use unscheduled care in future. This needs to be tested prospectively, because this understanding would be very helpful for health and social care planners in all countries where proactive holistic services exist
Multiple pathways to solve urban challenges: A shared portfolio approach towards smart city development
Get PDFMunicipalities often collaborate with other stakeholders in smart city projects to develop and implement technological innovations to address complex urban issues. We propose the shared portfolio approach as an alternative way of collaborating, because we have identified possible limitations when the commonly used single-project approach is adopted in complex contexts, such as the smart city context. The portfolio approach enhances flexibility, an embedded focus and cross-project learning, because partners work on multiple projects – either in parallel or in succession – to develop multiple solutions to a specific problem. An in-depth case study is used to illustrate how the shared portfolio approach works. In practice, these insights can be used by public bodies who aim to collaborate in smart city development or by partners who work on smart city projects and wish to continue their collaboration in a portfolio setting. Conceptually, our paper develops a connection between cross-sector partnership literature and smart city literature by revealing how the shared portfolio approach could be an effective way to deal with the complexities of innovation in the smart city context
Alpha 2 agonists for sedation to produce better outcomes from critical illness (A2B trial): protocol for a mixed-methods process evaluation of a randomised controlled trial
Get PDFIntroduction: An association between deep sedation and adverse short-term outcomes has been demonstrated although this evidence has been inconsistent. The A2B (alpha-2 agonists for sedation in critical care) sedation trial is designed to determine whether the alpha-2 agonists clonidine and dexmedetomidine, compared with usual care, are clinically and cost-effective. The A2B intervention is a complex intervention conducted in 39 intensive care units (ICUs) in the UK. Multicentre organisational factors, variable cultures, perceptions and practices and the involvement of multiple members of the healthcare team add to the complexity of the A2B trial. From our pretrial contextual exploration it was apparent that routine practices such as type and frequency of pain, agitation and delirium assessment, as well as the common sedative agents used, varied widely across the UK. Anticipated challenges in implementing A2B focused on the impact of usual practice, perceptions of risk, ICU culture, structure and the presence of equipoise. Given this complexity, a process evaluation has been embedded in the A2B trial to uncover factors that could impact successful delivery and explore their impact on intervention delivery and interpretation of outcomes. Methods and analysis: This is a mixed-methods process evaluation guided by the A2B intervention logic model. It includes two phases of data collection conducted during and at the end of trial. Data will be collected using a combination of questionnaires, stakeholder interviews and routinely collected trial data. A framework approach will be used to analyse qualitative data with synthesis of data within and across the phases. The nature of the relationship between delivery of the A2B intervention and the trial primary and secondary outcomes will be explored. Ethics and dissemination: All elements of the A2B trial, including the process evaluation, are approved by Scotland A Research Ethics Committee (Ref. 18/SS/0085). Dissemination will be via publications, presentations and media engagement
Distributed TDMA Scheduling for Autonomous Aerial Swarms: A Self-Organizing Approach
Get PDFSelf-organization is a key strategy for improving the performance of an aerial swarm ad hoc network. The proliferation of low-cost VTOL drones has broadened the application domain of aerial swarms, and the need for synchronized communication among network entities has become crucial. However, existing ad hoc approaches struggle to maintain multi-hop connections in contested environments characterized by frequent topology changes and intermittent links. To overcome these limitations, we introduced STDMA protocol, which enables the self-configuration of drones without reliance on a ground controller. In continuation of the earlier work, we conduct extensive experiments to evaluate the performance of the proposed protocol. Comparative simulation experiments cover various scenarios with different network sizes, frame lengths, and traffic loads. The STDMA protocol achieves optimal access delay in highly contested environments and reduces delay by approximately 19.181%. Moreover, it exhibits improved channel utilization compared to the E-ASAP/SM protocol, with a 4.5 times increase
Engine performance and emissions from a fumigated hydrogen/ammonia compression ignition engine with a hydrogen peroxide pilot
Get PDFThe study investigates, numerically, the potential use of introducing aqueous HO as an ignition promoter in a statistically homogeneous NH/H fuelled, medium speed (1250 rpm), 4-stroke, 1.3 litre cylinder displacement, mildly boosted CI engine with a compression ratio of 17.6:1. The H is considered to be produced on-board from ammonia cracking. An extensive campaign is undertaken using the commercial stochastic reactor model, SRM Engine Suite, which allowed the modelling of temporal, temperature and spatial stratification in the cylinder. The engine performance, combustion phasing, maximum pressure rise rate and emissions (NOx, NO and unreacted NH) are investigated in view of: (i) the share of molecular hydrogen in the initial NH/H mixture from 10 to 40 percent; (ii) the mass of aqueous HO introduced from 0.1 to 16 mg; (iii) the start of injection (−10 to ＋6 CAD aTDC) and duration of injection (1, 4 and 8 CAD); (iv) the amount of exhaust gas recirculation (up to 30 percent by mass); (v) the share of energy from the HO in the aqueous solution mixture at less than 0.5 percent of that in the main fuel; (vi) engine load corresponding to a variation in the equivalence ratio from 0.32 to 1.2 by changing the mass of the NH/H mixture in the combustion chamber. A wide range of loads (evaluated against the engine’s rated power when operated with diesel and at its rated boost levels) can be achieved (44%–93%) with the energy share of HO being as little as equivalent to 2.7% vol% that of the main fuel, ammonia, which is introduced into the cylinder. This implies that the required storage volume of the HO is low, at a few percent that of the main ammonia tank. NOx emissions peak between .6−0.65 and rapidly decrease as the equivalence ratio increases or decreases reaching values marginally above the Tier III standard at high loads (90%) while ammonia slip and NO emissions are generally extremely low (10−12 mg for NH and 0.01 mg/kWh for NO)
Training future engineers: Integrating Computational Thinking and effective learning methodologies into education
Get PDFThis article examines the effectiveness and interest generated among primary and secondary education students through activities aimed at developing Computational Thinking skills, in the context of the coronavirus disease 2019 pandemic. The shift to online or hybrid learning models posed a significant challenge for educators, particularly those lacking digital skills. The study sought to answer several research questions, including the impact of online versus in-person teaching on preuniversity students and gender differences in Computer Science perception, and Computational Thinking skills performance. The study employed a four-phase methodology, consisting of pre- and posttraining measurements of Computer Science perception and Computational Thinking skills development through specific activities delivered in-person or online. The results indicate that in-person training is more effective for developing Computational Thinking skills, particularly at the secondary education level. Furthermore, there is a need to focus on maintaining girls' interest in Computer Science during primary school, as interest levels tend to decline significantly in secondary school. These findings have significant implications for Engineering Education in the context of digital transformation and the increasing importance of Computational Thinking skills in various fields of engineering. This study highlights the importance of developing Computational Thinking skills among preuniversity students and the need for effective training methods to achieve this goal and underscore the significance of investing in Engineering Education to prepare the next generation of engineers for the rapidly changing digital landscape
Assistive technology: Occupational therapy assessment and services for people with dementia
Get PDFIntroduction:: Research suggests that services are not effectively providing suitable assistive technology for people with dementia. There is a need to understand the challenges facing practitioners to identify where service changes should be focussed to improve this situation. Method:: This study used an online survey to explore the experiences of 41 occupational therapists working with people with dementia, and/or assistive technology. Eight participants subsequently agreed to participate in online discussion groups. Group discussions were transcribed and checked. Data responses from group discussions and open questions in the survey were analysed thematically using the person-centred framework to identify domains supporting or obstructing effective assistive technology service delivery. Results:: Forty-one occupational therapist participants described challenges to providing person-centred assistive technology services. These included restricted access to assistive technology interventions, limited knowledge regarding developments in the field, variable funding, unsupportive systems, limited relevant training and difficulties working across health and social care sectors. Conclusion:: There is a need to revise the systems surrounding the provision of assistive technology for people with dementia. Occupational therapists need access to training relative to this field, and systems need to be adapted to support the provision of person-centred care by widening access to assistive technology
Data sources:
Access Repository Dashboard
Do you manage Repository@Napier? Access insider analytics, issue reports and manage access to outputs from your repository in the CORE Repository Dashboard!