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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.
目的以老龄化为背景,从福祉设计视野出发,通过对老年生活辅具设计研究,推动实现老年人独立自主参与社会活动来提升其福祉。方法以60岁以上、可生活自理的老年人为目标人群,采用访谈、现场观察等调研方式针对老年人的特殊需求进行梳理,结合文献及对经典设计的分析,总结老年生活辅具设计方法,并以后疫情下的地摊经济现象为例,进行多功能手推车的设计实证。结果提出福祉设计视野下老年生活辅具设计方法,设计出老年人多功能手推车方案。结论通过对老年生活辅具的设计,可以推动老年人独立自主参与社会活动进而提升其福祉;生活辅具设计应以老年人的生理、心理及行为特征为依归,结合产品设计规律,提出针对性的解决方案;老年手推车的设计可以帮助老年人在后疫情语境下独立自主地参与社会活动。 相似文献
3.
《International Journal of Hydrogen Energy》2022,47(69):29925-29944
Lithium iron phosphate battery (LIPB) is the key equipment of battery energy storage system (BESS), which plays a major role in promoting the economic and stable operation of microgrid. Based on the advancement of LIPB technology and efficient consumption of renewable energy, two power supply planning strategies and the china certified emission reduction (CCER) model are proposed respectively. Based on it, the multi-objective planning optimization model with economic benefits, environmental benefits and power supply stability as the objective function is established for the first time, and the Newton Weighted Sum Frisch method (NWSFA) solution model is adopted. In the planning process, rain flow counting method is used to research the life of BESS, which improves the accuracy of energy storage annual cost calculation. A park in northern China is taken as a case study to demonstrate the application of this model. The simulation results show that the annual economic operating cost of BESS is decreased by 18.81%, the energy supply reliability is increased by 0.15%, and the optimal electricity price adjustment ratio of the system is 15%. 相似文献
4.
随着社会的进步和发展,计算机网络通信技术已被应用到实际生活、生产的各个方面,对人们的生活、生产等产生了深刻的影响。为此,文章就计算机通信及网络远程控制技术在实际生活中的应用问题进行了探究,旨在借助先进科技促进社会实现更优质发展。 相似文献
5.
《International Journal of Hydrogen Energy》2022,47(57):23909-23918
The hydrogel electrolyte is an important part of safety and development potential in zinc-based energy storage equipment due to its inherent low mechanical strength and voltage decomposition. However, hydrogel electrolytes possess a reduced working life for zinc dendrites growth and a narrow voltage window. In this study, a hydrogel electrolyte prepares by the zwitterionic monomer [2-(methacryloyloxy)ethyl]dimethyl-(3-sulfopropyl) (MS) and sodium alginate (SA) alleviate these problems. The zwitterionic double-network hydrogel has good mechanical strength, inhibits the growth of zinc dendrites, enhances practicability, greatly increases the voltage window (0–2.4 V), and has self-healing properties to its rich functional groups. The assembled zinc-ion hybrid supercapacitors (ZHSs) have a high-power density of 172.33 W kg?1 and an energy density of 88.56 Wh·kg?1 at 0.5 A g?1. The assembled zinc-ion battery also has good electrochemical performance. Flexible ZHSs and batteries provide power to the timer stably under different bending angles. The zwitterionic double-network hydrogel can be applied to both zinc-based supercapacitors and batteries. 相似文献
6.
《Ceramics International》2022,48(8):10704-10712
A combination of high wear-resistance and low-friction is crucial for improving the wear performance of self-lubricating coatings, which is generally determined by an excellent lubricating effect and mechanical strength. In this study, the Mo–V–Cu–N coatings were prepared by HIPIMS technique with a spliced target of Mo–V–Cu at various charge voltages. The results revealed that Mo–V–Cu–N coatings presented a solid solution phase of B1–MoVN with (200) preferred orientation, and the preferred orientation was enhanced at high charge voltages. Whereas the Cu atoms formed an amorphous phase in Mo–V–Cu–N coatings due to a low Cu content of 2.3–3.6 at.%. As the charge voltage increased to 750 V, more charged metallic ions were accelerated and bombarded substrate surface efficiently, forming smooth and dense Mo–V–Cu–N coatings with a high hardness of 31.0 GPa. All the coatings presented a low friction coefficient of 0.34–0.39 due to the formation of MoO2, VO2 and CuO mixed oxides, and the wear mechanism was dominated by abrasive and tribo-oxidation wear at room temperature. 相似文献
7.
目的 探索湖北恩施地区西兰卡普的可持续设计策略。方法 分析隐身于贫困乡村的西兰卡普的文化价值和经济价值,对其进行设计转化的重要性与可行性分析;对湖北恩施地区西兰卡普进行实地考察与调研,梳理其可持续发展中所面临的传承主体和市场竞争方面的典型性困境与原由;以设计赋能传统手工艺作为设计扶贫的重要手段,基于西兰卡普所面临的困局系统性地提出其可持续性发展的设计策略。结论 在设计扶贫中,应构建多元主体参与、协同合作的再创新机制,注重强化造血能力,塑造地域名片,围绕当代消费需求,结合数字化技术进行展销模式、产品供给的升级和创新设计,并整合优势资源,实现产业的融合发展。总之,系统性地对西兰卡普进行设计赋能,是西兰卡普获得可持续性发展效力并助力当地贫困乡村经济发展的有效路径。 相似文献
8.
大数据时代,数据规模庞大,由数据进行驱动的应用分析场景日益增多.如何快速、高效地从这些海量数据中提取出用以分析决策的信息,给数据库系统带来重大挑战.同时,现代商业分析决策对分析数据的实时性要求数据库系统能够同时快速处理ACID事务和复杂的分析查询.然而,传统的数据分区粒度太粗,且不能适应动态变化的复杂分析负载;传统的数据布局单一,不能应对现代大量增加的混合事务分析应用场景.为了解决以上问题,“智能数据分区与布局”成为当前的研究热点之一,它通过数据挖掘、机器学习等技术抽取工作负载的有效特征,设计最佳的分区策略来避免扫描大量不相关的数据,指导布局结构设计以适应不同类型的工作负载.首先介绍了智能数据分区与布局的相关背景知识,然后对智能数据分区与布局技术的研究动机、发展趋势、关键技术进行详细的阐述.最后,对智能数据分区与布局技术的研究前景做出总结与展望. 相似文献
9.
Imbalance vibration is a typical failure mode of rotational machines and has significant negative effects on the effii-ciency,accuracy,and service life of equipment.To automatically reduce the imbalance vibration during the opera-tional process,different types of active balancing actuators have been designed and widely applied in actual produc-tion.However,the existing electromagnetic-ring active balancing actuator is designed based on an axial excitation structure which can cause structural instability and has low electromagnetic driving efficiency.In this paper,a novel radial excitation structure and the working principle of an electromagnetic-ring active balancing actuator with a combined driving strategy are presented in detail.Then,based on a finite element model,the performance param-eters of the actuator are analyzed,and reasonable design parameters are obtained.Self-locking torque measurements and comparative static and dynamic experiments are performed to validate the self-locking torque and driving effi-ciency of the actuator.The results indicate that this novel active balancing actuator has sufficient self-locking torque,achieves normal step rotation at 2000 r/min,and reduces the driving voltage by 12.5%.The proposed novel balancing actuator using radial excitation and a combination of permanent magnets and soft-iron blocks has improved electro-magnetic efficiency and a more stable and compact structure. 相似文献
10.
Dr. Remya Rajan Dr. Dirk Schepmann Ruben Steigerwald Dr. Julian A. Schreiber Dr. Ehab El-Awaad Prof. Joachim Jose Prof. Guiscard Seebohm Prof. Bernhard Wünsch 《ChemMedChem》2021,16(20):3201-3209
Recent studies have shown the involvement of GluN2A subunit-containing NMDA receptors in various neurological and pathological disorders. In the X-ray crystal structure, TCN-201 ( 1 ) and analogous pyrazine derivatives 2 and 3 adopt a U-shape (hairpin) conformation within the binding site formed by the ligand binding domains of the GluN1 and GluN2A subunits. In order to mimic the resulting π/π-interactions of two aromatic rings in the binding site, a [2.2]paracyclophane system was designed to lock these aromatic rings in a parallel orientation. Acylation of [2.2]paracyclophane ( 5 ) with oxalyl chloride and chloroacetyl chloride and subsequent transformations led to the oxalamide 7 , triazole 10 and benzamides 12 . The GluN2A inhibitory activities of the paracyclophane derivatives were tested with two-electrode voltage clamp electrophysiology using Xenopus laevis oocytes expressing selectively functional NMDA receptors with GluN2A subunit. The o-iodobenzamide 12 b with the highest similarity to TCN-201 showed the highest GuN2A inhibitory activity of this series of compounds. At a concentration of 10 μM, 12 b reached 36 % of the inhibitory activity of TCN-201 ( 1 ). This result indicates that the [2.2]paracyclophane system is well accepted by the TCN-201 binding site. 相似文献