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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 effect of surface roughness on the transient characteristics of the hydrodynamic cylindrical bearing during startup is studied. A mixed lubrication model considering both asperity contact and hydrodynamic fluid flow is solved. The asperity contact pressure is obtained by the Greenwood-Williamson (GW) contact model. The hydrodynamic pressure is calculated by modified average Reynolds equation with finite element method (FEM). The transient movement of the journal center, the transient average film thickness, the hydrodynamic pressure and the contact pressure are presented for different surface roughnesses. The contact time and contact zone in different types of surface roughness are obtained. The influences of the standard deviation of asperity height ( σ ) and rough surface patterns on these parameters are analyzed. The results show that the surface roughness has an important influence on the transient characteristics of the bearing during the initial period of startup. [ABSTRACT FROM AUTHOR]

The dynamic contact behavior of hydrodynamic journal bearings during start-up is investigated. The hydrodynamic oil force and asperity contact force are obtained by solving the mixed lubrication model. The motion of the journal center, the contact time, and the lift-off speed of the bearing are determined. The effects of the relative clearance and acceleration time are discussed. The result shows that the hydrodynamic oil force increases sharply during the early stage of the start-up process, leading to a sharp decrease in the contact force. An increase in the relative clearance of the bearing generates a decrease in both the contact force and the contact time. Also, a high start-up acceleration leads to a sharp decrease in the contact force. [ABSTRACT FROM AUTHOR]

In present work, in order to optimize partial slip zone for heavily loaded journal bearings, an isothermal hydrodynamic model considering wall slip occurring at oil-bush interface is built. Two-component slip model is utilized to calculate slip velocity. The performances of the journal bearing in different slip zone shapes and eccentricity ratios are evaluated. The optimal slip parameters in a range of eccentricity ratios are selected by considering their effects on hydrodynamic behavior, such as load carrying capacity and friction coefficient/torque. In addition, the application of optimal partial slip zone is presented. Results show that the optimal range of slip zone in high eccentricity ratio is quite restricted. The slip zone should be located at the convergent region of the film. The circumferential end of slip zone should locate at the convergent region and be close to the position of minimum film thickness. It is better to widen the axial length of slip zone, i.e. maximum rectangular shape could better improve bearing performance. • An isothermal hydrodynamic model considering wall slip occurring at oil-bush interface is built. • The performances of journal bearing in different slip zone shapes and eccentricity ratios are evaluated. • The optimal slip parameters in a constant load are selected with considering a range of eccentricity ratios. • The application of optimized partial slip zone in specific operations is presented. [ABSTRACT FROM AUTHOR]

After the publication of our article [1] we have been made aware of a number of mislabelling and reporting errors, which were introduced in the preparation of the manuscript. The conclusions are not affected by these errors and thus remain unchanged. [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]

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]

Objectives: Pre-stroke statin use reduces stroke severity and improves functional outcomes; however, whether low-dose statins as a primary preventive measure have similar effects on the Chinese population remains unclear. Methods: Consecutive cases of ischaemic stroke between May 2011 and January 2017 were retrospectively analysed. The primary endpoints were stroke severity on admission and functional outcomes at 90 days. The secondary endpoints were factors related to lower stroke severity on admission. Propensity score matching and logistic regression analyses were performed. Results: Of the 1878 patients, 6.4% and 23.8% were pre-stroke statin users before and after propensity matching, respectively, reducing the National Institutes of Health Stroke Scale (NIHSS) score on admission from 5 (2–9) to 3 (2–4) (P < 0.001). Patients receiving pretreatment with low-dose statins tended to have a better mRS distribution (median mRS score 2 [1–3] vs. 3 [2–4], P = 0.007) and a higher likelihood of favourable functional outcomes (FFOs) at 90 days (61 [65.6%] vs. 151 [50.8%], P = 0.005). The logistic regression analysis showed that low-dose statins taken before stroke (odds ratio [OR] = 0.15, 95% confidence interval [CI] = 0.08–0.27, P < 0.001) and being male (OR = 0.81, 95% CI = 0.66–0.99, P = 0.035) were related to a lower stroke severity on admission but not among patients with atrial fibrillation (OR = 1.65, 95% CI = 1.12–2.44, P = 0.012) or elevated white blood cell (WBC) counts (OR = 1.12, 95% CI = 1.08–1.17, P < 0.001). Conclusions: Pretreatment with low-dose statins reduced initial stroke severity, improved functional outcomes at 90 days and was independently associated with a lower stroke severity on admission among Chinese patients. [ABSTRACT FROM AUTHOR]