18624 research outputs found
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Assessment of mechanical properties by RVE modeling and simulation of recycled HDPE reinforced with carbon nanotubes
No full textThis study explores the integration of carbon nanotube (CNT) nanoparticles into recycled high-density polyethylene (rHDPE) composites to evaluate their mechanical properties. The Young’s modulus of rHDPE reinforced filled with tubular CNTs at various volume fractions (0.01, 0.02, 0.03, and 0.04) is predicted using a Representative Volume Element (RVE) model. The 0.04 rHDPE/CNT composites exhibit the highest enhancements in mechanical properties, such as 42% increase in Young’s modulus, a 39% improvement in tensile strength, a 49% rise in flexural strength, and a 20% surge in mode 1 frequency compared to pure rHDPE. Scanning Electron Microscope (SEM) fractography verifies the ductility behavior of virgin rHDPE and the brittleness nature of the 0.04 rHDPE/CNT composites. The RVE model’s predictions for Young’s modulus closely align with experimental results and demonstrate superior accuracy compared to micromechanical models. ANSYS simulation results for tensile strength (TS), flexural strength (FS), and frequency show less than a 10% error margin relative to the experimental value. This research supports using sustainable materials such as rHDPE/CNT to advance eco-friendly engineering solutions. © The Author(s), under exclusive licence to Springer-Verlag France SAS, part of Springer Nature 2024
Advancements in Underground Infrastructures
No full textAdvancements in Underground Infrastructures presents the advanced modelling tools and experimental techniques applied in underground infrastructure development. It examines the usage of mathematical tools, experimental techniques, and data-driven models, as well as the latest technological advancements in underground engineering used to enhance the safety and stability of underground structures. It also addresses the application of the circular economy model in underground engineering. Provides modelling theories in an easy-to-read format verified by on-site models for various regions and scenarios; Presents applications of soft computing tools and techniques in underground engineering; Includes practical examples and case studies. Colour versions of the figures in this book can be found at www.routledge.com/9781032373379. © 2025 selection and editorial matter, Manoj Khandelwal, Danial Jahed Armaghani, Ramesh Murlihar Bhatawdekar, Pijush Samui, and Saffet Yagiz individual chapters, the contributors
Estimating soil organic carbon from multispectral images using physics-informed neural networks
No full textUnderstanding the amount of Soil Organic Carbon (SOC) at farm and field scale is a necessary precursor to effective management, important for both agricultural productivity and to reduce CO2 emissions. To avoid the prohibitive cost of measurement, SOC can be estimated by using multispectral images. In this study, we propose a novel Physics-Informed Convolutional Neural Network (CNN) to model well-known but noisy relationship between a soil index and SOC using the network’s loss function. This study is also conducted by resampling the European Land Use/Classification Area Survey (LUCAS) dataset to Sentinel-2 bands. Our experimental results show that our proposed network converges more quickly, has a lower root mean squared error (RMSE) and is more robust (as measured by the standard deviation of RMSE over multiple trials) than a compatible standard CNN. The operation of the novel Physics-Informed CNN is explained in terms of the components of the loss function. © The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd. 2025
Adapting a self-guided ehealth intervention into a tailored therapist-guided ehealth intervention for survivors of colorectal cancer
Full text linkTherapist-guided eHealth interventions have been shown to engage users more effectively and achieve better outcomes than self-guided interventions when addressing psychological symptoms. Building on this evidence, this viewpoint aimed to describe the adaptation of iConquerFear, a self-guided eHealth intervention targeting fear of cancer recurrence, into a therapist guided version (TG-iConquerFear) tailored specifically for survivors of colorectal cancer (CRC). The goal was to optimize patient outcomes while minimizing the need for extensive resources. The adaptation process followed the Information System research framework, which facilitated a systematic integration of knowledge and iterative testing. Drawing on insights from the original iConquerFear development, as well as feedback from end users, oncologists, and therapists, we began by identifying areas for improvement. These insights formed the foundation for the first design cycle. Initial internal testing revealed the need for several adjustments to enhance the intervention. While the core concept of iConquerFear remained unchanged, we made significant modifications to improve access by optimizing the platform for mobile devices, to support adherence by expanding the exercises, and to equip therapists with tools such as reflective questions and a monitoring control panel. External field testing with 5 survivors of CRC provided further validation. Participants reported a high level of acceptability, and their feedback guided additional minor points to consider incorporating in future versions. This study illustrates how a self-guided eHealth intervention can be successfully adapted into a therapist-guided format for fear of cancer recurrence, tailored to meet the needs of survivors of CRC. The described approach serves as a valuable framework for integrating therapist guidance into similar interventions, ensuring their relevance and effectiveness for targeted populations. © Johanne Dam Lyhne, Allan 'Ben' Smith, Tina Birgitte Wisbech Carstensen, Lisa Beatty, Adeola Bamgboje-Ayodele, BrittKlein, Lars Henrik Jensen, Lisbeth Frostholm
Cross-domain fake news detection through fusion of evidence from multiple social media platforms
Full text linkFake news has become a significant challenge on online social platforms, increasing uncertainty and unwanted tension in society. The negative impact of fake news on political processes, public health, and social harmony underscores the urgency of developing more effective detection systems. Existing methods for fake news detection often focus solely on one platform, potentially missing important clues that arise from multiple platforms. Another important consideration is that the domain of fake news changes rapidly, making cross-domain analysis more difficult than in-domain analysis. To address both of these limitations, our method takes evidence from multiple social media platforms, enhances our cross-domain analysis, and improves overall detection accuracy. Our method employs the Dempster–Shafer combination rule for aggregating probabilities for comments being fake from two different social media platforms. Instead of directly using the comments as features, our approach improves fake news detection by examining the relationships and calculating correlations among comments from different platforms. This provides a more comprehensive view of how fake news spreads and how users respond to it. Most importantly, our study reveals that true news is typically rich in content, while fake news tends to generate a vast thread of comments. Therefore, we propose a combined method that merges content- and comment-based approaches, allowing our model to identify fake news with greater accuracy and showing an overall improvement of 7% over previous methods. © 2025 by the authors
Wind speed probability distribution based on adaptive bandwidth kernel density estimation model for wind farm application
Full text linkWind speed variables play an important role in exploiting wind power. However, they are fluctuating and random. Therefore, understanding their characteristics and properties is necessary to improve exploitation efficiency. This research investigates various wind speed distribution models, both parametric and nonparametric, to estimate wind speed probability density (WSPD). The distribution models are implemented on various wind speed datasets with distribution characteristics of varying complexity. The assessment of goodness of fit includes statistical tests including Cramér-von Mises (CvM), Anderson-Darling (A-D), Kolmogorov-Smirnov (K-S), and chi-square ((Formula presented.)), along with indices correlated as mean absolute percent error (MAPE). The study highlights that the adaptive bandwidth kernel density estimation (AKDE) distribution model based on the nearest neighbor estimation (NNE) has superior goodness of fit performance. Wind turbine power curves are applied to calculate and compare expected, distribution-based, and empirical power output. In addition, the difference between the power output estimated from the AKDE distribution and the estimate from the empirical wind speed is almost zero, so this estimated power is reliable and can be used as a reference for planning or evaluating wind farm efficiency. © 2024 The Author(s). Wind Energy published by John Wiley & Sons Ltd
Preseason and in-season high-speed running demands of 2 professional Australian rules football teams
Full text linkBackground: Australian Rules Football athletes complete long preseasons, yet injuries occur frequently at early stages of the competitive season. Little is known about the high-speed running (HSR) prescription during a preseason or whether players are adequately prepared for competition. This study described absolute and relative preseason and in-season HSR demands of 2 professional Australian football teams. Hypothesis: HSR and sprinting volumes are significantly lower in elite Australian Rules football athletes during in-season compared with preseason. Study Design: Cohort study. Level of Evidence: Level 3. Methods: During the 2019 season, HSR volume was collected for 2 professional Australian football teams (n = 55). Individual maximum speeds (Vmax) were captured to calculate relative running speed thresholds, as reported in 5% increments from 70%Vmax to 100%Vmax. Results: Weekly volume of running above 70%Vmax (P = 0.01; r = 0.56) and 80%Vmax (P = 0.01; r = 0.58) was significantly greater in the preseason than the in-season. The weekly volume completed above 90%Vmax was not significantly greater in the preseason than the in-season (P = 0.10; r = 0.22). Individual variation in the distance completed at specific percentages of Vmax expressed as a coefficient of variation was reported as 51% at 71% to 80%Vmax, 39% at 81% to 90%Vmax, and 41% at 91% to 100%Vmax. Conclusion: The volume of HSR completed by athletes is far greater in the initial 4 weeks of the preseason than in any other point in preseason or competitive phases. At the individual level, there is substantial variation in the distance covered. This supports the concept of a heavily individualized approach to high-speed prescription and monitoring. Clinical Relevance: Practitioners should carefully consider individual variation regarding sprinting volume during both preseason and in-season when prescribing and monitoring training to improve on-field performance and reduce the risk of injury. © 2024 The Author(s)
Negative prior aquatic experiences and children's aquatic competency : do parent perceptions differ from reality?
Full text linkIssue Addressed: Achieving aquatic competence is recommended for preventing childhood drownings, yet many children in Victoria, Australia do not meet aquatic benchmarks despite participating in swimming and water safety programs. While few studies have explored factors influencing aquatic competency development, negative prior aquatic experiences (NPAE) have surfaced as a potential influence. Research on children's NPAE has primarily focused on parental perceptions rather than the child's actual experiences. Methods: Parents and children (aged 10–12 years) completed reliable surveys for background information and NPAE-related data. Children also completed aquatic competency assessments against benchmark standards. Chi-square tests determined relationships between NPAE and aquatic competency, and thematic analysis categorised themes related to perceptions of the child's NPAE. Results: Most parents (82.9%) indicated their child had not had NPAE, while only half (51.0%) of children did not report NPAE. Children reporting NPAE often perceived incidents as nearly drowning (41%), encompassing swimming pool environments and underwater submersion. Similarly, parents reported varied situations, noting NPAE involving open water and the child's loss of control. Parent-reported NPAE was associated with children less likely to achieve knowledge, continuous swimming, and survival competency benchmarks (p <.05). Children reporting NPAE were less likely to achieve underwater competencies (p <.05). Conclusions: The disparity between parent and child perspectives of NPAE demonstrates the importance of considering both perspectives. This should assist in providing appropriate support for children to develop aquatic competencies. So What?: Using NPAE data, practitioners can customise swim teaching approaches to address and prevent NPAE, particularly as many children associate their NPAE with pools, the common setting for aquatic education. © 2024 The Author(s). Health Promotion Journal of Australia published by John Wiley & Sons Australia, Ltd on behalf of Australian Health Promotion Association
Multiple-voltage-vector model-free predictive deadbeat control with updated reference voltage vector for PMSM drive
No full textModel predictive control (MPC) has been extensively investigated for its impressive dynamic response and efficacy in controlling non-linear systems. However, MPC faces challenges in terms of robustness, primarily due to its dependency on system parameters. In contrast, model-free predictive control (MFPC) offers an alternative that relies on the inputs and outputs of the system without applying system parameters in each control period. To avoid the problem of the stator current gradient update stagnation existing in the conventional MFPC strategy, this article proposes an enhanced MFPC strategy based on a novel reference voltage vector (VV) updating mechanism. In the proposed strategy, the reference VVs for the present control period are determined by evaluating the difference between the reference current and the sampling current, which is related to the previously calculated VVs of the contiguous control period. By substituting the current gradient with the updated reference VVs, the proposed strategy effectively reduces the interferences arising from inaccurate current gradients, enhancing the steady-state performance of the system. The proposed MFPC is verified using a laboratory 0.5 kw permanent magnet synchronous motor drive setup. © 1986-2012 IEEE
The multiple errands test–home version and its association with driving potential : a pilot study
No full textImportance: Driving is a complex occupation requiring the interplay of high-level cognitive, physical, sensory, and behavioral skills for safe performance. Occupational therapists need to routinely address driving with adults as an occupational performance area. Further research is needed to determine whether performance-based assessment tools can support occupational therapists in screening client driving potential. Objective: To conduct a pilot study to determine whether the Multiple Errands Test–Home Version (MET–Home), as a performance-based assessment, either alone or in combination with other assessments, should be further investigated for use by occupational therapists to screen clients’ driving potential. Design: Cross-sectional pilot study. Setting: Private in-clinic and community setting, including participants’ homes. Participants: Convenience sampling recruited 28 participants through private occupational therapy driver assessors. Outcomes and Measures: Participants underwent a comprehensive in-clinic and behind-the-wheel assessment, as per standard practice, and three additional cognitive tests. Data were summarized with descriptive statistics, and univariate analyses were used to examine the relationships between cognitive assessment scores and driving outcomes. Results: The MET–Home, as a stand-alone tool and in combination with other cognitive assessment scores, was not associated with driving outcomes (pass–fail). However, participant self-assessment of their MET–Home performance was associated with driving outcomes (pass–fail; p = .014). Conclusions and Relevance: Although our findings suggest that the MET–Home is unlikely to screen for driving potential, further research of performance-based assessment tool use by occupational therapists is needed to support identification of the optimal type and timing of client referral for comprehensive assessment. Plain-Language Summary: The Multiple Errands Test–Home Version (MET–Home) is commonly completed by occupational therapists. Although this pilot study revealed that MET–Home scores were not associated with driving outcomes, performance-based assessments such as the MET–Home have the potential to guide occupational therapists when screening clients to determine when further, comprehensive assessment is indicated. © 2025 American Occupational Therapy Association, Inc. All rights reserved