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1.
《International Journal of Hydrogen Energy》2022,47(85):36216-36231
The fuel cell/battery durability and hybrid system stability are major considerations for the power management of fuel cell hybrid electric bus (FCHEB) operating on complicated driving conditions. In this paper, a real time nonlinear adaptive control (NAC) with stability analyze is formulated for power management of FCHEB. Firstly, the mathematical model of hybrid power system is analyzed, which is established for control-oriented design. Furthermore, the NAC-based strategy with quadratic Lyapunov function is set up to guarantee the stability of closed-loop power system, and the power split between fuel cell and battery is controlled with the durability consideration. Finally, two real-time power management strategies, state machine control (SMC) and fuzzy logic control (FLC), are implemented to evaluate the performance of NAC-based strategy, and the simulation results suggest that the guaranteed stability of NAC-based strategy can efficiently prolong fuel cell/battery lifespan and provide better fuel consumption economy for FCHEB. 相似文献
2.
高面板坝的变形对面板的安全运行有着特别重要的影响,国内外已建的高面板坝工程中,因坝体变形大导致防渗面板挤压破损,坝体渗漏量大的实例较多,不得不降低水库水位进行修复处理,造成较大的经济损失乃至给大坝的长期运行留下安全隐患。通过发生挤压破损的实例分析,发现变形控制缺乏系统性是发生面板挤压破损的主要因素,为预防面板破损,系统提出了“控制坝体总变形,转化有害变形,适应纵向变形”的坝体变形控制方法,并在使用软硬岩混合料筑坝的董箐面板堆石坝中得到的应用,取得了良好效果,该工程运行至今达十余年,未见面板有挤压破损迹象,该方法对建设200 m以上乃至300 m级超高面板坝具有重要借鉴意义。 相似文献
3.
Mobile Networks and Applications - Inverse kinematics is an important basic theory in walking control of biped robot. This study focuses on the parameter setting using the improved algorithm in... 相似文献
4.
《Journal of the European Ceramic Society》2022,42(11):4456-4464
A series of 3 C-SiC coatings were prepared by organometallic chemical vapor deposition (MOCVD) using precursor solution containing a varying proportion of commercial-grade hexamethyldisiloxane (HMDSO) and n-hexane. The phase composition, bonding state, and microstructure of 3 C-SiC coatings were studied in detail by grazing incidence X-ray diffraction (GIXRD), Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), and scanning electron microscopy (SEM). The microstructure and mechanical properties of the optimal 3 C-SiC coating were characterized by scanning transmission electron microscopy (STEM) and nanoindentation, respectively. Our results revealed that the amount of undesired graphite phase can be significantly reduced in the 3 C-SiC coating by introducing hydrogen gas in the reaction chamber alongside increasing the ratio of HMDSO/n-hexane in the precursor mixture. The STEM results revealed that the optimal coating was predominantly composed of nano-crystalline 3 C-SiC grains alongside a small amount of amorphous graphite. The hardness and elastic modulus of the optimal coating were 38.19 GPa and 363.2 GPa, respectively. 相似文献
5.
高效率地使用工程车辆是工程项目管理中节约成本的有效方法,无人监管环境下工程车辆的工况识别,是实现工程车辆高效率使用的有效手段。目前以GPS等技术为核心的车辆智能管理系统未对工程车辆进行工况识别,提出一种基于GRU循环神经网络的工程车辆工况识别方法,通过对工程车辆在不同工况下产生的音频信号进行分析,从中提取Mel倒谱系数作为主要特征,构建GRU循环神经网络模型进行训练和识别。实验结果表明,该方法可以实现对工程车辆工况的有效识别。 相似文献
6.
Xiao Chen Minlan Yuan Yuting Wang Yan Zhou Xiaohong Sun 《International Journal of Food Science & Technology》2022,57(5):2670-2679
The present study aimed to evaluate the effect of fermentation and gastrointestinal digestion of three kinds of fermented kiwifruit pulps with different Lactobacillus (Lactobacillus plantarum, Lactobacillus acidophilus and Lactobacillus casei). The changes in bioactive substances (total phenolic acid, total flavonoid, vitamin C and the viable count), antioxidant capacity (DPPH, ABTS, hydroxyl radical and superoxide anion radical scavenging activity) and phenolic profiles (protocatechuic acid, protocatechualdehyde, chlorogenic acid, caffeic acid and p-coumaric acid) were detected. The result showed, compared to non-fermented kiwifruit pulp, fermentation with LP and LA had higher content of TPA, TF and VC, as well as antioxidant capacity. Fermentation with LP and the content of protocatechualdehyde, p-coumaric acid and chlorogenic acid were increased. However, after digestion, LP showed more effect in maintaining the content of antioxidants, antioxidant capacity and the viable count rather than LA. During digestion, the content of protocatechualdehyde and p-coumaric acid was increased in fermented samples compared with non-fermented samples. Overall, compared with LA and LC, LP is more suitable for the fermentation of kiwifruit pulp. 相似文献
7.
8.
Luo Xin Yufeng Zhang Wenshan Duan Mingyan Ai Hongbo Song Qun Huang Jiankang Lu 《International Journal of Food Science & Technology》2022,57(5):2646-2655
Oil, accounting for 45% of almonds, is easily oxidised and can further induce the protein oxidation to reduce their quality. Structure and physicochemical properties of amandin, the main water-soluble protein in almonds, inducing oxidation by malondialdehyde (MDA) were investigated. The results showed that the content of carbonyl group increased from 5.23 to 33.25 nmol mg−1 of protein with the increase in MDA concentration (P < 0.05). However, the sulphydryl content, surface hydrophobicity, particle size and the absolute value of ζ-potential first increased and then decreased. Fourier-transformed infrared spectroscopy (FT-IR) confirmed that the structure of amandin changed from order to disorder. Fluorescence spectroscopic analysis revealed that mild oxidation (0–0.1 mmol L−1 MDA) exposed hydrophobic groups of the protein. Sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE) suggested that protein oxidation promoted crosslinking between protein molecules. Furthermore, protein oxidation markedly declined the total amino acid content of amandin (P < 0.05). In conclusion, MDA oxidation changed the structure and amino acid content of amandin, and caused the protein aggregate and crosslink through hydrophobic interaction and electrostatic interaction. 相似文献
9.
《Ceramics International》2022,48(10):14192-14200
In this study, mold powder slurries with high solid loading and low viscosity were prepared during the ball-milling process for improving the homogeneity and mechanical properties of granules after spray-drying. The effect of ball-milling parameters, such as solid loading, binder/dispersant content, and ball-milling time, on the flowability, dispersibility, stability, and rheological behavior of mold powder slurries was systematically investigated by rheology observation and sedimentation tests. As these parameters varied, the slurry exhibited the shear-thinning behavior of a non-Newtonian fluid with a shear rate range of 0–50 s?1, which was adequately described by the Herschel-Bulkley model. The optimal parameters that optimized the flowability, dispersibility, and stability of the slurry, along with its rheological behavior, were chosen as follows: solid loading, 60 wt%; modified sodium carboxymethyl cellulose binder content, 1.0 wt%; sodium tripolyphosphate dispersant content, 0.5 wt%; ball-milling time, 60 min. 相似文献
10.