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A self-data-driven approach for online remaining useful life prediction of machinery using a recursive update strategy
No full textData availability:
Data will be made available on request.Self-data-driven remaining useful life (RUL) prediction of machinery has gained significant attention in engineering due to its potential to reduce dependency on extensive training data during the prediction process. However, existing self-data-driven methods typically necessitate the storage and reuse of entire historical degradation data for updating prediction models, which limits their applicability in online and real-time scenarios. To overcome this limitation, this paper proposes a self-data-driven method for online RUL prediction using a recursive update strategy. Unlike conventional methods, the proposed recursive update strategy updates model parameters and selects the optimal model based on the latest monitoring data. A model base consisting of various degradation functions is initially established. During online prediction, model parameters are continuously updated in real-time using a sequential Bayesian algorithm, while the optimal degradation model is automatically identified using the proposed recursive Bayesian information criterion (RBIC). The effectiveness of this approach is validated through both simulation and experimental case studies. The results demonstrate that the proposed method not only achieves higher prediction accuracy but also requires less computation time compared to existing methods in online applications.This work was supported by the National Natural Science Foundation of China (52025056, 52375121 and 52435003), “Scientists & Engineers” Team Construction Project of Shaanxi Qinchuangyuan (2022KXJ-028), Shaanxi Science and Technology Innovation Team (2023-CX-TD-15), and Fundamental Research Funds for the Central Universities
Structured Pattern Discovery Using Dictionary Learning for Incipient Fault Detection and Isolation
Get PDFTo address the challenges encountered by dictionary learning-based monitoring, this article presents a novel pattern discovery scheme for detection and isolation of incipient faults that involves structured sparse coding and sequential dictionary augmentations. Through learning a basic dictionary for normal pattern and augmenting the low-dimensional sparse dictionaries for analyzing different fault patterns, the process signals can be decomposed into fault-free and fault-related components. To guarantee the in-statistical-control status of the fault-free part and improve detection sensitivity, a & ell;(2)-penalty is imposed on the sum of coefficient vectors to ensure that the monitoring statistic related to the fault-free part will not exceed the control limit. In addition, two Frobenius norm penalties are imposed on the zero centered coefficient matrix and atom matrix to improve the robustness of signal decomposition. Instead of imposing & ell;(1)-sparsity constraint on the atoms, a hard sparsity constraint is used to correctly select fault-related feature variables, so that fault patterns can be better revealed. The informative dictionaries are then incorporated into the moving window-based monitoring strategy, yielding a fault detection and isolation scheme suitable for incipient faults. The superior performance of our proposed approach is validated by application studies involving a numerical example and two practical industrial processes.This work was supported primarily by the “Pioneer and Leading Goose + X” S&T Project of Zhejiang Province (Grant No. 2025C01022), and partially by the Hangzhou Joint Fund of Zhejiang Provincial Natural Science Foundation (Grant No. LHZSZ24F020002)
Enhanced Near-Field Shock Wave Propagation in Underwater Explosion with Air-Tube
No full textIn this paper, enhanced near-field shock wave propagation in underwater explosion is achieved by introducing a fragile air-tube under the explosive. Firstly, based on the ALE algorithm in the ANSYS/LS-DYNA software, a numerical model integrating the water, the air, the explosive, and the air-tube is developed. Comparative discussion for explosion with air-tube in the air, as well as explosion in the water without air-tube, is made to highlight the distinct energy attenuation mechanism due to the introduction of the air-tube. Then, the influence of the tube geometry, as well as evolving structural boundaries, on the explosive process is discussed exhaustively. The results indicate that the air-tube acts as a shock focusing apparatus, significantly altering explosion flow dynamics. Tube damage mode relies on tube geometrical size. Time-refreshed structural boundary affects the position the fluid flowing into the air-tube, which in turn plays an impact on the bubble pattern and energy distribution near the tube outlet. Enhanced outlet pressure is strengthened along with the decrease of the outlet radius, cross-section height ratio and tube thickness. These insights offer valuable guidance for optimizing underwater explosion and possess prospectively scientific and practical significance.The support from the National Natural Science Foundation of China (Grant No. 12172040) is acknowledged
Finite element simulation of masonry wall behavior: Exploring various brick bonds and load conditions
No full textThe objective of this document is to study the mechanical response of masonry structures with three different forms of assemblies, and subject to different loads (lateral and cyclic). Simulations are conducted using Abaqus software, employing the finite element method. The validity of the model is verified by taking into account the experimental and numerical results available in the literature. The "stretcher bond," the traditional bond commonly employed in masonry walls, and two newly proposed brick bonds known as "single basket-weave" and "double basket-weave" are the three types of brick bonds that are analyzed and interpreted. Additionally, the effect of reinforcement using composite materials (a strip of fiberglass) is studied for the wall with the connection type “stretcher bond”. A new form of composite materials strip is adopted for the reinforcement study, the choice of this new position and shape is based on the results observed in the first section of this document. The failure mode and load-displacement curves for each case are depicted and interpreted. The final step involves simulating models with openings of different sizes and positions relative to the wall (wall with a stretcher bond). The results show that the type of brick bond influences the deformation mechanism as well as its resistance to rupture. Indeed, the wall (with stretcher bond) exhibits high load resistance compared to other types of bonds. This analysis also demonstrates that reinforcing masonry wall with composite materials helps improve his resistance to cyclic loading. Finally, the presence of openings (their locations and sizes) can affect the response of the studied wall, as these openings lead to a decrease in the wall's resistance compared to samples without openings
Measurement of event shapes in minimum-bias events from proton-proton collisions at √s = 13 TeV
Get PDFA version of the article is available at arXiv:2505.17850v2 [hep-ex] (https://arxiv.org/abs/2505.17850). Comments: Replaced with the published version. Added the journal reference and the DOI. All the figures and tables can be found at https://cms-results.web.cern.ch/cms-results/public-results/publications/SMP-23-008 (CMS Public Pages). Subjects: High Energy Physics - Experiment (hep-ex). Report number: CMS-SMP-23-008, CERN-EP-2025-041. Journal reference: Phys. Rev. D 112 (2025) 112006. Related DOI: https://doi.org/10.1103/rqvb-gfb7 . From: The CMS Collaboration: [v1] Fri, 23 May 2025 13:03:03 UTC (664 KB); [v2] Sat, 13 Dec 2025 17:48:49 UTC (701 KB).Data Availability:
Release and preservation of data used by the CMS Collaboration as the basis for publications is guided by the CMS data preservation, reuse, and open access policy [80]. CMS data availability statement [https://opendata.cern.ch/record/415].A measurement of event-shape variables is presented, using a data sample produced in a special run with approximately one inelastic proton-proton collision per bunch crossing. The data were collected with the CMS detector at a center-of-mass energy of 13 TeV, corresponding to an integrated luminosity of 64μb⁻¹. A number of observables related to the overall distribution of charged particles in the collisions are corrected for detector effects and compared with simulations. Inclusive event-shape distributions, as well as differential distributions of event shapes as functions of charged-particle multiplicity, are studied. None of the models investigated are able to satisfactorily describe the data. Moreover, there are significant features common amongst all generator setups studied, particularly showing data being more isotropic than any of the simulations. Multidimensional unfolded distributions are provided, along with their correlations.SCOAP³
What Motor Skills Do Children Perceive as Important? A Child-Centred Exploration Using the Motor Coordination Questionnaire
Get PDFSummary:
Children in South Africa and Ghana identified self-care, neat writing and household chores as highly important, while the perceived importance of specific motor activities varied according to cultural and environmental context.
Sex-related differences in activity importance were evident, with boys placing greater importance on ball skills and team sports and girls valuing dancing more highly.
Children with probable developmental coordination disorder (pDCD) rated many motor activities as less important than typically developing children, suggesting that motor difficulties may influence perceived meaningfulness of participation.
Children's perceptions of important activities were shaped by sociocultural context, gender norms and motor coordination, underscoring the need for child-centred and culturally responsive approaches in assessment, intervention and physical activity promotion.Data Availability Statement:
Data are available on request due to privacy/ethical restrictions.Background:
Understanding children's perceptions of motor skill importance is essential for designing motivating and participatory interventions. However, little is known about which motor activities children with and without motor coordination difficulties value, particularly in culturally diverse, low-resource settings. This study explored how children perceive the importance of motor activities and how these views are shaped by cultural context, sex and motor skill level.
Methods:
A culturally adapted version of the motor coordination questionnaire (MoCQ) was administered to 1438 children aged 6–13 years in South Africa and Ghana. The MoCQ includes sections on perceived competence (MoCQ-C) and perceived importance (MoCQ-I). Motor skill level was assessed using the Movement Assessment Battery for Children, Second Edition in South Africa and the Developmental Coordination Disorder Questionnaire in Ghana. Children were classified into two motor coordination groups: as typically developing (TD) or having probable developmental coordination disorder (pDCD). Importance ratings from the MoCQ-I were compared across countries, sex and motor coordination groups.
Results:
Total MoCQ-I scores differed significantly between countries (p < 0.001, d = 0.235), sex (p = 0.031, d = 0.134) and motor coordination groups (p < 0.001, d = 0.335). Children in both countries rated self-care, handwriting and household chores as highly important. Ghanaian children rated kicking, throwing, running, hopping and indigenous games more often as important. South African children gave a higher importance rating to handwriting. Males rated kicking, team sports and biking as more important, whereas females rated dancing higher. Differences between TD and pDCD groups at the item level were more pronounced in Ghana compared to South Africa.
Conclusion:
Children's perceptions of motor activity importance are shaped by cultural context, sex and motor proficiency. These findings highlight the need for culturally responsive, child-centred interventions. While the MoCQ-I effectively captures key activities, further expansion is recommended to enhance cultural inclusivity and relevance.The authors received no specific funding for this work
Influences of general and specific psycho‐social factors on cognitive health of sexual minority older adults
Get PDFClinical Manifestations Poster Presentation: Neuropsychology at the Alzheimer’s Association International Conference (AAIC25), Toronto, Canada, 27-31 July 2025.Background:
Sexual minorities (i.e. people who identify as non-heterosexual) show several health disparities. However, risk/protective factors relevant to cognitive health of sexual minority older adults (SMOAs) have not been fully investigated. The aim of this study was to quantify the impact of several psycho-social factors on subjective and objective cognitive health in SMOAs.
Method:
Thirty-nine cognitively unimpaired SMOAs (age = 64.1±10.0; M = 74.4%) and 30 heterosexual older adults (HOAs; age = 65.6±9.7; M = 40.0%) completed an online survey to provide information on psycho-social risks (i.e., depression, anxiety, general stress), subjective cognitive decline (SCD), beliefs about their memory and dementia worries. SMOAs also completed questionnaires on minority stress and outness. Twenty-seven SMOAs and 24 HOAs underwent a comprehensive neuropsychological battery. General linear models were used to assess the relationship between psycho-social risk factors and cognitive health and the interactions between sexual orientation and risk factors. Minority stress and outness were also investigated as risk/protective factors for cognitive health in SMOAs only.
Result:
Compared with HOAs, SMOAs reported worse mental and subjective cognitive health (i.e. SCD for memory, negative memory beliefs and dementia worries), but similar cognitive performance. Worse depression/anxiety were associated with more dementia worries in both groups, while anxiety was associated with worse performance on the Trail Making Test in SMOAs only (Figure 1). Moreover, worse minority stress was associated with higher risk of SCD for language (OR = 6.79, p = 0.048) and more negative memory beliefs (b = 0.41, p = 0.012), while being more out about one's own sexual orientation was associated with better short-term memory performance (b = 0.54, p = 0.004).
Conclusion:
This is the first targeted study highlighting that SMOAs experience more detrimental effects of anxiety than HOAs on attentional functions. Minority stress primarily affects subjective cognitive health of SMOAs, while outness appears to provide resilience against cognitive decline. Further investigations are needed to ascertain longitudinal cognitive changes and to devise potential prevention strategies aimed at preserving cognitive health in SMOAs
A method for correcting the substructure of multiprong jets using the Lund jet plane
Get PDFData Availability Statement. Release and preservation of data used by the CMS Collaboration as the basis for publications is guided by the CMS data preservation, re-use and open access policy.Code Availability Statement. The CMS core software is publicly available on GitHub.A preprint version of the article is available at arXiv:2507.07775v2 [hep-ex], https://arxiv.org/abs/2507.07775 .
Comments: Replaced with the published version. Added the journal reference and the DOI. All the figures and tables can be found at https://cms-results.web.cern.ch/cms-results/public-results/publications/JME-23-001 (CMS Public Pages). Report number: CMS-JME-23-001, CERN-EP-2025-128. Journal reference: JHEP 11 (2025) 038. Submission history: From: The CMS Collaboration:
[v1] Thu, 10 Jul 2025 13:56:23 UTC (596 KB); [v2] Mon, 17 Nov 2025 18:27:04 UTC (733 KB)Many analyses at the CERN LHC exploit the substructure of jets to identify heavy resonances produced with high momenta that decay into multiple quarks and/or gluons. This paper presents a new technique for correcting the substructure of simulated large-radius jets from multiprong decays. The technique is based on reclustering the jet constituents into several subjets such that each subjet represents a single prong, and separately correcting the radiation pattern in the Lund jet plane of each subjet using a correction derived from data. The data presented here correspond to an integrated luminosity of 138 fb − 1 collected by the CMS experiment between 2016–2018 at a center-of-mass energy of 13 TeV. The correction procedure improves the agreement between data and simulation for several different substructure observables of multiprong jets. This technique establishes, for the first time, a robust calibration for the substructure of jets with four or more prongs, enabling future measurements and searches for new phenomena containing these signatures.SCOAP3
Understanding customer conversations in social media support interactions: divergent sentiments in material and experiential brands
Get PDFData Availability Statement:
The data that support the findings of this study are available from the corresponding author upon
reasonable request.
The data used in this study was collected from Twitter in 2018, prior to the 2023 policy changes
implemented by X (formerly Twitter). During the time of data collection, our study fully complied
with Twitter’s data use and scraping policies.Supplementary data are available online at: https://www.emerald.com/gkmc/article-abstract/doi/10.1108/GKMC-02-2025-0098/1317508/Understanding-customer-conversations-in-social?redirectedFrom=fulltext#supplementary-data .Purpose:
This study aims to investigate how customer sentiments differ in social media interactions with customer support accounts of material and experiential brands. It seeks to understand the impact of these interactions on customer sentiment dynamics and their implications for customer support strategies.
Design/methodology/approach:
Drawing on experiential recommendation literature, this study employs a sentiment analysis approach to analyze 60,000 tweets directed at customer support accounts of three experiential and three material brands on X (formerly known as Twitter). Regression analysis is also applied to investigate the influence of post characteristics and content types (e.g. emojis) on sentiment.
Findings:
Results reveal significant differences between material and experiential brands in both overall sentiment and sentiment evolution during customer support interactions. Conversations with experiential brands exhibit more positive overall sentiments; whereas interactions with material brands demonstrate a greater positive sentiment shift despite initially exhibiting more negative sentiments. The findings also show that tweet length is a strong predictor of customer sentiment.
Originality/value:
This research underscores the unique roles of material and experiential brands in shaping customer sentiment during social media interactions. The study provides novel insights into online customer support dynamics and offers actionable recommendations for improving after-sales management strategies in social media contexts.This research received no specific grant from any funding agency in the public, commercial, or not-for-profit sectors
Noise-tolerant fixed-time leader-follower consensus controller design for multi-agent systems via fuzzy-neural-network
No full textThe leader-follower consensus control problem in multi-agent systems (MASs) is critical and has received significant attention. However, the simultaneous achievement of fixed-time stability and robustness is often challenging in MASs due to their inherent complexity and uncertainty. This paper developed a controller based on the proposed noise-tolerant fixed-time fuzzy neural network (NF-FNN) model to realize the leader-follower consensus of MASs. Specifically, the introduction of an integral error term makes the NF-FNN model have powerful noise tolerance, and a fuzzy gain parameter generated by the Takagi-Sugeno fuzzy logic system makes the NF-FNN model have fuzzy adaptiveness. In addition, a new partition-sign-by-power activation function is developed to ensure fixed-time stability of the NF-FNN model. Theoretical analysis and comparative simulations confirm the superb swift stability and excellent noise tolerance of controllers based on the NF-FNN model for achieving the leader-follower consensus of MASs, as compared with existing methods.This work was supported in part by the Natural Science Foundation of Hunan Province of China under Grant 2022RC1103 and Grant 2024JJ6320, and in part by the National Natural Science Youth Foundation of China under Grant 62406109
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