Accuracy improvement of fuel cell prognostics based on voltage prediction

Proton exchange membrane fuel cell (PEMFC) is a promising hydrogen technique with various application prospects. However, all the PEMFCs are subject to degradation resulting from mechanical and chemical aging. To tackle this challenge, accurately predicting fuel cell degradation is essential for its durability optimization. In this study, an enhanced data-driven prognostic framework is developed to accurately predict short-term and medium-term degradation using only fuel cell voltage as the input feature. Firstly, a local outlier factor (LOF) algorithm is adopted for automatic detection of outliers in raw data collected from actual sensing environments. Then, an advanced deep learning model, residual–CNN–LSTM-random attention, is proposed to optimize voltage prediction to better indicate future PEMFC degradation trend. The proposed work is validated by the IEEE PHM 2014 Data Challenge. Compared to state-of-the-art methods, the proposed framework provides superior prediction accuracies with high stability. For instance, the framework improves short-term prediction, achieving a root mean square error (RMSE) of 0.0021 and a mean absolute percentage error (MAPE) of 0.0323 at steady state when training stops at 600 h. For medium-term prediction, our method also attains better results with an RMSE of 0.0085 and a MAPE of 0.4237 under same working conditions. Additionally, the comparative analyses demonstrate a lower computational burden and higher suitability of proposed work for practical applications

Online systemic energy management strategy of fuel cell system with efficiency enhancement

Temperature plays a crucial role in efficiency improvement and lifespan extension of the fuel cell system which encourages energy management strategy (EMS) taking thermal into consideration. However, sluggish thermal response prevents the fuel cell performance from tracking the optimal states during scenarios with significant power variations, which was disregarded in the previous works. To solve this issue, an online hydrogen consumption minimization guarantee strategy (HCMG) including thermal management is proposed which is divided into two parts: 1) primary power distribution strategy, where a model predictive control (MPC) based EMS is employed herein to distribute power between fuel cell and battery with the objectives of minimizing hydrogen consumption as well as maintaining the state of charge (SOC), and 2) HCMG, where a modified MPC based method is exploited herein to track the reference power and optimal temperature with minimum hydrogen consumption by adjusting both the duty cycle of fan and fuel cell current. The presented approach ascertains hydrogen consumption reduction for 3.448% even under relatively extensive power changes, during which the temperature cannot reach the optimal value in a brief time. The real-time simulation results show the effectiveness of the proposed technique compared with previous EMS methods under various driving cycles

Adsorption of thallium(I) on rutile nano-titanium dioxide and environmental implications

Rutile nano-titanium dioxide (RNTD) characterized by loose particles with diameter in 20–50 nm has a very large surface area for adsorption of Tl, a typical trace metal that has severe toxicity. The increasing application of RNTD and widespread discharge of Tl-bearing effluents from various industrial activities would increase the risk of their co-exposure in aquatic environments. The adsorption behavior of Tl(I) (a prevalent form of Tl in nature) on RNTD was studied as a function of solution pH, temperature, and ion strength. Adsorption isotherms, kinetics, and thermodynamics for Tl(I) were also investigated. The adsorption of Tl(I) on RNTD started at very low pH values and increased abruptly, then maintained at high level with increasing pH >9. Uptake of Tl(I) was very fast on RNTD in the first 15 min then slowed down. The adsorption of Tl(I) on RNTD was an exothermic process; and the adsorption isotherm of Tl(I) followed the Langmuir model, with the maximum adsorption amount of 51.2 mg/g at room temperature. The kinetics of Tl adsorption can be described by a pseudo-second-order equation. FT-IR spectroscopy revealed that -OH and -TiOO-H play an important role in the adsorption. All these results indicate that RNTD has a fast adsorption rate and excellent adsorption amount for Tl(I), which can thus alter the transport, bioavailability and fate of Tl(I) in aqueous environment

The forerunner of modern collective residence in Hankou: the study on Panoffs’ Mansion

Collective residence is the choice of urban residents for residential buildings in the context of urban intensification and population densification in modern times. Starting from the modern collective residence in the former concession area of Hankou, this paper, with the focus on Panoffs’ Mansion in the former Russian Concession, through field investigation and literature, original spatial pattern was deduced according to the current situation. Through the diagram analysis of its spatial sequence and organization, and comparative analysis with other collective residence in Hankou, to discuss the similarities and differences between the mansion and other modern Hankou collective residence in form, layout, internal space pattern and living mode. The urban texture of concession completely different form Hankou Old Town, but regional elements are integrated. Panoffs’ Mansion has these common characteristics. Moreover, its volume occupies a single block, and it is the earliest unit residence in Hankou. Panoffs’ Mansion is the earliest practice of unit housing in Hankou, which plays a leading role in modern housing in Hankou. The study of its spatial organization and architectural form is of great significance to the study of modern housing in Hankou concession

Multi-Sensor Building Fire Alarm System with Information Fusion Technology Based on D-S Evidence Theory

Multi-sensor and information fusion technology based on Dempster-Shafer evidence theory is applied in the system of a building fire alarm to realize early detecting and alarming. By using a multi-sensor to monitor the parameters of the fire process, such as light, smoke, temperature, gas and moisture, the range of fire monitoring in space and time is expanded compared with a single-sensor system. Then, the D-S evidence theory is applied to fuse the information from the multi-sensor with the specific fire model, and the fire alarm is more accurate and timely. The proposed method can avoid the failure of the monitoring data effectively, deal with the conflicting evidence from the multi-sensor robustly and improve the reliability of fire warning significantly

C/S and B/S mixed structure-based students ideological and political work management system construction

Nowadays, both single C/S, B/S cannot meet each department demands, for students ideological and political work management construction, it needs C/S, B/S mixed structure to jointly complete, the paper carries out advantages and disadvantages analysis and judgment on C/S, B/S single structure, on this basis, utilizes AHP model to analyze C/S, B/S mixed structure in ideological and political work management system, and gets that C/S, B/S mixed structure obtained recognition degree in students’ ideological and political work management is the highest, and analyzes from the ideological and political teachers’ operation ability, the students ability to use, ideological and political management system maintenance, and the degree of system coverage four aspects, and gets students ideological and political work management system’s system construction strength in C/S, B/S mixed structure

Physiological and Psychological Effects of Nature Experiences in Different Forests on Young People

Many studies have proved that having nature experiences in forests is conducive to human physiological and psychological health. However, currently there is little research focusing on the effects of forest characteristics and the experiential characteristics of nature experiences on changes in health. In the study, three types of forest (mixed forest; deciduous forest; coniferous forest) and an urban site were used to measure the effects of these environments on participants’ physiological and psychological restoration after nature experience activities (sitting and walking activities). The study participants were 30 young adult students from Beijing Forestry University. Restorative effects were measured by physiological indicators (blood pressure and heart rate) and four psychological questionnaires (Profile of Mood States (POMS); Restorative Outcome Scale (ROS); Subjective Vitality Scale (SVS); Warwick-Edinburgh Mental Well-being Scale (WEMWBS)). Results demonstrated that all types of forest were beneficial to lower blood pressure and heart rate as well as to reduce negative feelings while boosting positive emotions. The mixed forest was more effective in lowering blood pressure and heart rate as well as increasing vitality. The levels of restoration and positive mental health increased significantly, while all subscales of the POMS (with the exception of vigor) decreased greatly in the coniferous forest. Relative to the sitting activity, obvious decreases in blood pressure and negative emotions were observed, while significant increases in restoration, vitality and positive mental health were observed after the walking activity. In conclusion, the impact on subjects’ health restoration varied with different forest characteristics, and the experiential characteristics of exposure may be helpful for creating supportive interventions and lifting the benefits of forest therapy as people interact with the forest

Alamandine via MrgD receptor attenuates pulmonary fibrosis via NOX4 and autophagy pathway

Alamandine (ALA) and its receptor MrgD were recently identified as components of the renin-angiotensin system (RAS), which confer protection against cardio-fibrosis and renal-fibrosis. However, the effects of ALA on pulmonary fibrosis are unknown. This study was designed to serve two goals: (1) to evaluate ALA/MrgD axis ability in the prevention of Angiotensin Ⅱ (Ang Ⅱ)-induced pulmonary fibrosis in fibroblasts. (2) to determine the effect of ALA in bleomycin (BLM) treated C57B/6 mice. In vivo experiments revealed that the treatment of C57B/6 mice with ALA prevented BLM-induced fibrosis and these findings were similar to those reported for pirfenidone. The anti-fibrosis actions of ALA were mediated via alleviation of oxidative injury and autophagy induction. In addition, in vitro studies revealed that ALA treatment attenuated Ang Ⅱ-induced α-collagen I, CTGF and α-SMA production in fibroblast which was blocked by D-Pro7-Ang-(1-7), an MrgD antagonist. This led to alleviation of oxidative injury and induction of autophagy similar to that reported for rapamycin. This study demonstrated that ALA via MrgD receptor reduced pulmonary fibrosis through attenuation of oxidative injury and induction of autophagy.The accepted manuscript in pdf format is listed with the files at the bottom of this page. The presentation of the authors' names and (or) special characters in the title of the manuscript may differ slightly between what is listed on this page and what is listed in the pdf file of the accepted manuscript; that in the pdf file of the accepted manuscript is what was submitted by the author

Frequency of TLR 2, 4, and 9 Gene Polymorphisms in Chinese Population and Their Susceptibility to Type 2 Diabetes and Coronary Artery Disease

Toll-like receptors (TLRs) are pivotal components of the innate immune response. Activation of the innate immune system and subsequent chronic low-grade inflammation are thought to be involved in the pathogenesis of atherosclerosis and type 2 diabetes. In the study, we genotyped TLRs gene polymorphisms, including TLR2 Arg677Trp and Arg753Gln, TLR4 Asp299Gly and Thr399Ile, TLR9-1486T/C and -1237T/C. The frequencies of TT, TC and CC genotype of TLR9-1486T/C mutation were 39.6%, 45.8% and 14.6%, respectively; the frequencies of T allele and C allele were 62.5% and 37.5%. However, neither of these parameters was statistically significant among study groups. In addition, we were surprised to find that the commonly reported TLR SNPs in the Western countries, like TLR2 Arg677Trp or Arg753Gln, TLR4 Asp299Gly or Thr399Ile and TLR9-1237T/C, were not polymorphic at all in all study subjects. In conclusion, our data suggests that TLR2 Arg677Trp or Arg753Gln, TLR4 Asp299Gly or Thr399Ile and TLR9-1237T/C polymorphisms have low frequency and TLR9-1486T/C polymorphism may not be a suitable marker in predicting the susceptibility to type 2 diabetes or coronary artery disease in the Chinese Han population