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Bearing health is key for maintaining good performance and safety in rotating machinery. As the diagnosis of mechanical faults develops toward intelligence and automation, accurate and systematic fault diagnosis algorithms are imperative. Focusing on the diagnosis of rolling bearing failures, this study utilizes a sliding time window to extract essential data segments. A series of signal processing techniques, including filtering, amplitude–frequency analysis, Hilbert envelope analysis, and energy analysis, is applied to establish a comprehensive dataset. For extraction of the hidden properties of the data, the recurrence quantity spectrum is defined for the input of the neural network. The goal is to obtain a cleaner dataset with enhanced features. A convolution neural network is constructed. Different activation functions in the activation layer are compared for better fault diagnosis algorithms. The established feature matrices are specifically defined to accurately identify the subtlest defects of bearings, thereby facilitating early detection. The proposed procedure distinguishes various fault modes. As for the multidimensional complexities of fault signals, this study carries out a comprehensive comparison of energies, recurrence quantification, and amplitude–frequency characteristics of bearing fault detection to assess the accuracy, computational efficiency, and robustness of bearing fault diagnosis. The proposed method and bearing fault detection procedures have potential in practical applications. [ABSTRACT FROM AUTHOR]

In this paper, hydroxyapatite (HAP) was synthesized by clean and simple multi-scan cycle voltammetry. The crystal structure and functional group of intermediate products calcium hydrogen phosphate dihydrate (DCPD) and hydroxyapatite(HAP) were characterized by X-ray diffraction and infrared spectroscopy. Scanning electron microscope showed that the surface of HAP was a rod-like structure with good dispersion. Taking fluorine ions in water as adsorption objects, the effects of the parameters such as pH, possible coexistence anions and temperature on the adsorption capacity of synthesized HAP were studied. The results showed that in the range of pH of 3-6, the adsorption capacity of HAP to fluorine ions gradually increased with the increase of pH and reached the maximum when the pH was 6; in the range of pH of 6-10, and the adsorption of HAP to fluorine ions gradually decreased with the increase of pH. Anions that may coexist in water, such as Cl-, NO3-, SO2-4, CO2-4, did not interfere with HAP adsorption of fluorine ions. In the range of temperature of 15-55 °C, the adsorption capacity of HAP increased with the temperature increase, and reached the maxum of 8.36 mg/g at 55 °C, which was higher than the similar materials reported . After 4 times of adsorptiondesorption experiments, the removal effect of HAP on fluoride ions in simulated wastewater was still in line with the national standard. In addition, the adsorption of fluorine ions by HAP was a spontaneous process of entropy increase and heat absorption, which conformed to the adsorption isothermal models of Langmuir-Freundlich and Dubinin-Radushkevich, and followed the kinetic reaction mechanism of intra particle diffusion. [ABSTRACT FROM AUTHOR]

Objective of this study is to assess the clinical performance of a urine-based high-risk human papillomavirus (hrHPV) test for the detection of cervical intraepithelial neoplasia grade 2 or higher (CIN2+).Methods: Between September and December 2021, women aged 20 to 65 years referred to colposcopy clinic were prospectively recruited at three clinical centers in China. Paired urine and cervical specimens from all enrolled women were obtained for hrHPV DNA fluorescence quantitative PCR test. The results of liquid-based cytology (LBC), colposcopy and diagnostic biopsies were collected. We evaluated the sensitivity and specificity for CIN and assessed the agreement/kappa value.Results: A total of 732 women (median age, 40 years) with valid results were included in the study, and 130 (17.8%) women were histologically confirmed as CIN2+. The sensitivity of urine and cervical test for CIN2+ and CIN3+ were 87.69% and 85.45%, respectively. The specificity of urine test performed better than cervical test in women with Conclusion: The data suggested that the urine-based hrHPV test may be an alternative approach for cervical cancer screening. [ABSTRACT FROM AUTHOR]

With their high-energy density, high-power density, long life, and low self-discharge, lithium-ion capacitors are a novel form of electrochemical energy storage devices which are extensively utilized in electric vehicles, energy storage systems, and portable electronic gadgets. Li-ion capacitor aging mechanisms and life prediction techniques, however, continue to be active research areas. This paper examines the aging process for Li-ion batteries, covering the alterations in cell composition, the effect of the electrode charge state, temperature effects, and electrolyte deterioration. Additionally, this research offers approaches for predicting the lifespan of lithium-ion batteries, including those based on physical models, machine learning, and artificial intelligence. In this work, cycle life testing techniques are also discussed, including accelerated aging experiments for lithium-ion capacitors. The paper concludes by discussing future directions for the creation of aging mechanisms and lithium-ion capacitor life prediction techniques. [ABSTRACT FROM AUTHOR]

With the rapid development of smart grids and distributed energy sources, the home energy management system (HEMS) is becoming a hot topic of research as a hub for connecting customers and utilities for energy visualization. Accurate forecasting of future short-term residential electricity demand for each major appliance is a key part of the energy management system. This paper aims to explore the current research status of household-level short-term load forecasting, summarize the advantages and disadvantages of various forecasting methods, and provide research ideas for short-term household load forecasting and household energy management. Firstly, the paper analyzes the latest research results and research trends in deep learning load forecasting methods in terms of network models, feature extraction, and adaptive learning; secondly, it points out the importance of combining probabilistic forecasting methods that take into account load uncertainty with deep learning techniques; and further explores the implications and methods for device-level as well as ultra-short-term load forecasting. In addition, the paper also analyzes the importance of short-term household load forecasting for the scheduling of electricity consumption in household energy management systems. Finally, the paper points out the problems in the current research and proposes suggestions for future development of short-term household load forecasting. [ABSTRACT FROM AUTHOR]

The Portevin–Le Chatelier effect of Cu–2.0Be alloy was investigated using hot isothermal compression at varying strain rates (0.01–10 s−1) and temperature (903–1063 K). An Arrhenius-type constitutive equation was developed, and the average activation was determined. Both strain-rate-sensitive and temperature-sensitive serrations were identified. The stress–strain curve exhibited three types of serrations: type A at high strain rates, type B (mixed A + B) at medium strain rates, and type C at low strain rates. The serration mechanism is mainly affected by the interaction between the velocity of solute atom diffusion and movable dislocations. As the strain rate increases, the dislocations outpace the diffusion speed of the solute atoms, limiting their ability to effectively pin the dislocations, resulting in lower dislocation density and serration amplitude. Moreover, the dynamic phase transformation triggers the formation of nanoscale dispersive β phases, which impede dislocation and cause a rapid increase in the effective stress required for unpinning, leading to the formation of mixed A + B serrations at 1 s−1. [ABSTRACT FROM AUTHOR]

A thermohydrodynamic model was used to study the influence of partial composite coatings on the behavior of plain journal bearings, considering solid elastic deformations and wall slip occurring at the oil film–polytetrafluoroethylene coating interface, and heat conduction between film, coating, interlayer and basement. The purpose is to design partial polytetrafluoroethylene coating to obtain improved bearing behavior based on analyzing the maximum temperature and minimum film thickness in different coating positions (or slip zones). The influences of coating thickness and coating materials (polytetrafluoroethylene, graphite and diamond-like carbon coatings) at different coating positions are also presented. Results show that polytetrafluoroethylene coatings that are completely located in the film convergent region have a small influence on thermal behavior in both nonslip and slip cases. Without slip, a full polytetrafluoroethylene coating can increase the maximum temperature; however, wall slip occurring on a full polytetrafluoroethylene coating surface is helpful in decreasing the maximum temperature when accompanied by a lower minimum film thickness. A thicker polytetrafluoroethylene coating causes bearing seizures more readily. Unlike polytetrafluoroethylene, graphite and diamond-like carbon coatings improve the thermal behavior. [ABSTRACT FROM AUTHOR]

Background: Although vascular dementia is the second most common cause of dementia globally, evidence-based treatments are still lacking. Cerebrolysin is a porcine brain-derived preparation that is said to have neurotrophic and neuroprotective activity. In many parts of the world Cerebrolysin, given as a series of daily intravenous infusions, is used as a potential intervention for vascular dementia. A previous Cochrane Review on Cerebrolysin in vascular dementia yielded inconsistent results. We wished to update the review to add new studies from the international literature and employ contemporary methods for appraising the strength of the evidence. This is the first update of a review first published in 2013., Objectives: Primary: to assess the effect of Cerebrolysin on cognitive function, global function, and all-cause mortality in people living with vascular dementia. Secondary: to assess the adverse effects of Cerebrolysin and to assess the effect of Cerebrolysin on quality of life and caregiver burden., Search Methods: We searched ALOIS, MEDLINE, Embase, PsycINFO, CINAHL, ISI Web of Knowledge, LILACS, the Cochrane Library, ClinicalTrials.gov, and the WHO ICTRP on 16 June 2017, 9 May 2018, and 9 May 2019. We expanded the search by adding four Chinese databases, searched from 1 January 2012 to 19 May 2019. We checked bibliographies of relevant papers identified and contacted pharmaceutical companies, trial authors, and experts in the field to identify any additional published or unpublished data., Selection Criteria: We included all randomised controlled trials of Cerebrolysin used in people living with vascular dementia. We applied no language restriction., Data Collection and Analysis: Two review authors independently selected trials for inclusion and evaluated their methodological quality. Data were extracted and analysed using mean differences (MDs) or standardised mean differences (SMDs) with 95% confidence intervals (95% CI) for continuous outcomes. We reported dichotomous outcomes as risk ratio (RR) with 95% CI. We assessed the strength of the available evidence using the GRADE approach., Main Results: We identified six randomised controlled trials with a total of 597 participants that were eligible for inclusion in the 2013 review. No new studies were eligible for inclusion in this update. Participants in the included studies, where dementia severity was reported, had mild to moderate severity of vascular dementia (four trials). The included studies tested varying doses and duration of Cerebrolysin treatment. Follow-up ranged from 15 days to three years. Five of included studies were conducted in China (three studies), Russia (one study), and Romania (one study), while relevant information of other study was unclear. Where details of funding were available, all studies were supported by the pharmaceutical industry (three studies). Cognitive function was measured using the Mini-Mental State Examination (MMSE) or Alzheimer's Disease Assessment Scale Cognitive Subpart, extended version (ADAS-cog+). Combining the MMSE and ADAS-cog+ data (three studies, 420 people), there was a beneficial effect of Cerebrolysin (SMD 0.36, 95% CI 0.13 to 0.58; very low-quality evidence). Global function was measured by Clinician's Interview-Based Impression of Change plus Caregiver Input (CIBIC+) or Investigator's Clinical Global Impression (CGI). We assessed response rates on these measures (the proportion of participants with a CIBIC+ score of < 3; or at least moderate improvement of the CGI rating at the last visit). There was a beneficial effect of Cerebrolysin (two studies, 379 participants, RR 2.69, 95% CI 1.82 to 3.98; very low-quality evidence). Only one trial described mortality and reported no deaths. Four studies reported adverse events; data from two studies (379 people) were in a format that permitted meta-analysis, and there was no difference in rates of adverse effects (RR 0.91, 95% CI 0.29 to 2.85; very low-quality evidence). No studies reported on quality of life or caregiver burden., Authors' Conclusions: Courses of intravenous Cerebrolysin improved cognition and general function in people living with vascular dementia, with no suggestion of adverse effects. However, these data are not definitive. Our analyses were limited by heterogeneity, and the included papers had high risk of bias. If there are benefits of Cerebrolysin, the effects may be too small to be clinically meaningful. There have been no new studies of Cerebrolysin in vascular dementia since the last Cochrane Review. Cerebrolysin continues to be used and promoted as a treatment for vascular dementia, but the supporting evidence base is weak. Adequately powered, methodologically robust trials are needed to properly assess the effects of Cerebrolysin in vascular dementia., (Copyright © 2019 The Cochrane Collaboration. Published by John Wiley & Sons, Ltd.)