Fast Charging of Lithium-Ion Batteries Using Deep Bayesian Optimization with Recurrent Neural Network

Fast charging has attracted increasing attention from the battery community for electrical vehicles (EVs) to alleviate range anxiety and reduce charging time for EVs. However, inappropriate charging strategies would cause severe degradation of batteries or even hazardous accidents. To optimize fast-charging strategies under various constraints, particularly safety limits, we propose a novel deep Bayesian optimization (BO) approach that utilizes Bayesian recurrent neural network (BRNN) as the surrogate model, given its capability in handling sequential data. In addition, a combined acquisition function of expected improvement (EI) and upper confidence bound (UCB) is developed to better balance the exploitation and exploration. The effectiveness of the proposed approach is demonstrated on the PETLION, a porous electrode theory-based battery simulator. Our method is also compared with the state-of-the-art BO methods that use Gaussian process (GP) and non-recurrent network as surrogate models. The results verify the superior performance of the proposed fast charging approaches, which mainly results from that: (i) the BRNN-based surrogate model provides a more precise prediction of battery lifetime than that based on GP or non-recurrent network; and (ii) the combined acquisition function outperforms traditional EI or UCB criteria in exploring the optimal charging protocol that maintains the longest battery lifetime

Harvesting time and biomass composition affect the economics of microalgae production

Cost simulations provide a strong tool to render the production of microalgae economically viable. This study evaluated the unexplored effect of harvesting time and the corresponding microalgal biomass composition on the overall production cost, under both continuous light and light/dark regime using techno-economic analysis (TEA). At the same time, the TEA gives evidence that a novel product “proteinaceous salt” from Dunaliella microalgae production is a promising high-value product for commercialization with profitability. The optimum production scenario is to employ natural light/dark regime and harvest microalgal biomass around late exponential phase, obtaining the minimum production cost of 11 €/kg and a profitable minimum selling price (MSP) of 14.4 €/kg for the “proteinaceous salt”. For further optimization of the production, increasing microalgal biomass concentration is the most effective way to reduce the total production cost and increase the profits of microalgae products

Diagnostic value of serum LDH in children with refractory Mycoplasma pneumoniae pneumoniae: A systematic review and meta-analysis

BackgroundTo investigate the relationship between serum Lactate dehydrogenase (LDH) and refractory Mycoplasma pneumoniae pneumonia (RMPP) in juvenile individuals.MethodsSearch Chinese databases and English databases. The retrieval time limit is from the establishment of the database to 2022-04-27. And screening and inclusion of relevant diagnostic test literature. The QUADAS-2 method was used to evaluate the quality of the included literature. The random effects model was used to combine sensitivity, specificity, likelihood ratio, diagnostic odds ratio, summary receiver operating characteristic curve, and area under summary receiver operating characteristic curve to evaluate the prediction value of LDH for RMPP. Subgroup analyses were used to explore sources of heterogeneity.Results① A total of 29 literatures that met the criteria were included in the study, and the quality of the literature was medium and high, with a total of 702,2 patients. ② The combined sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, diagnostic odds ratio, and area under the curve of the studies were: 0.75 (95% CI = 0.73–0.76), 0.73 (95% CI = 0.72–0.74), 3.61 (95% CI = 2.86–4.56), 0.30 (95% CI = 0.23–0.39), 13.04 (95% CI = 8.24–20.63), and 0.85(95% CI = 0.82–0.88). ③ The results of subgroup analysis showed that Compared with the subgroup with LDH threshold ≤400 IU/L, the AUC increased from 0.84 (95% CI = 0.80–0.87) to 0.89 (95% CI = 0.86–0.91).ConclusionsThe serum LDH has good accuracy for the diagnosis of RMPP and can serve as a diagnostic marker for RMPP

Association of abnormal lung function and its subtypes with arterial stiffness: A longitudinal cohort study

BACKGROUND: Prior studies have reported the cross-sectional relationship between lung function and arterial stiffness, while the longitudinal association remains unclear to date. This study aimed to investigate whether abnormal lung function and its subtypes at baseline are associated with increased arterial stiffness using a cohort. METHODS AND RESULTS: This was a secondary analysis extracting 2461 participants from Beijing Health Management Cohort as baseline and annually followed for development of arterial stiffness. Abnormal lung function was defined by forced expiratory volume in 1s \u3c 80% of the predicted value, forced vital capacity of the predicted value, or forced expiratory volume in 1s/ forced vital capacity ratio \u3c 70%. Increased arterial stiffness was determined by brachial-ankle pulse wave velocity ≥ 1400 cm/s. Cox proportional hazards model was used to calculate the hazard ratio and population attributable fraction. The mean age was 42.8±8.1 years, and 444 (18.0%) cases developed increased arterial stiffness during a median follow-up of 3.0 years. The adjusted hazard ratio (95% CI) of arterial stiffness was 1.47 (95% CI, 1.10–1.96) for abnormal lung function, with a population attributable fraction of 3.9% (95% CI, 0.8–7.1). Of subtypes, only obstructive ventilatory dysfunction was significantly associated with arterial stiffness (adjusted hazard ratio, 2.06 [95% CI, 1.27–3.36]), not restricted ventilatory dysfunction (adjusted hazard ratio, 0.95 [95% CI, 0.54–1.65]). Consistent results were observed on multiple sensitivity analyses. CONCLUSIONS: Our study indicated a longitudinal association of abnormal lung function with increased arterial stiffness using a large cohort, especially for the obstructive ventilatory dysfunction

The effectiveness of interpretive methods in informal educational facilities : an experimental study with reference to marine parks

Interpretation has been used in many tourism sectors as a technique in achieving building hannony between resources and human needs. The objectives of this study are to identify the types of the interpretive methods used, and to evaluate their effectiveness, in marine parks. This study reviews the design principles of an effective interpretation for marine wildlife tourism, and adopts Drams' five design principles (1997) into a conceptual framework. Enjoyment increase, knowledge gain, attitude and intention change, and behaviour modification were used as key indicators in the assessment of the interpretive effectiveness of the Vancouver Aquarium (VA) and Marineland Canada (MC). Since on-site research is unavailable, a virtual tour is created to represent the interpretive experiences in the two study sites. Self-administered questionnaires are used to measure responses. Through comparing responses to the questionnaires (pre-, post-virtual tours and follow-up), this study found that interpretation increased enjoyment and added to respondents' knowledge. Although the changes in attitudes and intentions are not significant, the findings indicate that attitude and intention changes did occur as a result of interpretation, but only to a limited extent. Overall results suggest that more techniques should be added to enhance the effectiveness of the interpretation in marine parks or self-guiding tours, and with careful design, virtual tours are the innovative interpretation techniques for marine parks or informal educational facilities

Preparation of a Poly (Ether-b-Amide) Mixed-Matrix Membrane and Its Application in Blast Furnace Gas

In this paper, we propose the use of nanomaterials to build three-dimensional structured gas-separation membranes to accommodate more gas molecules. SWCNT provides a fast passage for gas molecules, while GO can make gas molecules have more adsorption sites due to its large specific surface and the fact that its special lamellar folds can hinder the transport of macromolecules. Graphene oxide (GO) was prepared by an improved Hummer’s method, and single-walled carbon nanotubes (SWCNTs) were purified by mixed acid treatment. Then, Pebax1657 particles were dissolved in a reflux setup at 80 °C, and GO/SWCNT/Pebax1657 mixed-matrix membrane (MMM) was prepared by solution blending. Finally, the permeability and selectivity of GO/SWCNT/Pebax1657 membrane to single gas and mixed gas at different temperature and inlet pressure were investigated

Experiment on Corrosion Fatigue Life of Steel Strands under the Coupling Effects of Chloride Environment and Alternating Loads

Corrosion pits will lead to local stress concentration on the surface of steel strands and even shorter fatigue life and worse mechanical properties of steel strands. In order to explore the corrosion mechanics of steel strands to predict the fatigue life, accelerated salt spray corrosion test is carried out to simulate the corrosion laws of steel strands and record the changes of the corrosion degrees during the experiment, considering the coupling effects of alternating loads and chloride environment. Besides, the impact of stress amplitudes on the corrosion degrees of steel strands is quantitatively studied by the corrosion weight loss, and corroded steel strands in experiment are graded according to the corrosion weight loss to test the mechanical properties, respectively; the results show that the corrosion weight loss and tensile strength of steel strands obey the exponential distribution, and the relationship with elongation is linear. In addition, the relationships between the stress concentration coefficient and the pit length, width, and depth are obtained; with the three-dimensional linear regression theory, the accuracy of the regression model is verified by t-value test, laying a foundation for predicting the corrosion life of the cables