Developing advanced battery-type materials with abundant active sites,high conductivity,versatile morphologies,and hierarchically porous structures is crucial for realizing high-quality hybrid supercapacitors.Herein,h...Developing advanced battery-type materials with abundant active sites,high conductivity,versatile morphologies,and hierarchically porous structures is crucial for realizing high-quality hybrid supercapacitors.Herein,heterogeneous FeS@NiS is synthesized by cationic Co doping via surface-structure engineering.The density functional theory(DFT)theoretical calculations are firstly performed to predict the advantages of Co dopant by improving the OH^(−)adsorption properties and adjusting electronic structure,benefiting ions/electron transfer.The dynamic surface evolution is further explored which demonstrates that CoFeS@CoNiS could be quickly reconstructed to Ni(Co)Fe_(2)O_(4)during the charging process,while the unstable structure of the amorphous Ni(Co)Fe_(2)O_(4)results in partial conversion to Ni/Co/FeOOH at high potentials,which contributes to the more reactive active site and good structural stability.Thus,the free-standing electrode reveals excellent electrochemical performance with a superior capacity(335.6 mA h g^(−1),2684 F g^(−1))at 3 A g^(−1).Furthermore,the as-fabricated device shows a quality energy density of 78.1 W h kg^(−1)at a power density of 750 W kg^(−1)and excellent cycle life of 92.1%capacitance retention after 5000 cycles.This work offers a facile strategy to construct versatile morphological structures using electrochemical activation and holds promising applications in energy-related fields.展开更多
Aimed at the complex flight control system of a fighter,a kind of robust adaptive control methods using multiple models is presented to make the control system track the given signal under different working conditions...Aimed at the complex flight control system of a fighter,a kind of robust adaptive control methods using multiple models is presented to make the control system track the given signal under different working conditions and to reconfigure the control law for some structural failures. Firstly,the multiple-model control structure is formed by several linear models and one fuzzy model. In the fuzzy logic way,weights of the multiple-model adaptive controller are obtained. Then,a dynamic structure adaptive neural network is introduced to stabilize the whole system and eliminate the influence caused by the frequent switching. Simulation results show that the control method is effective by demonstrating the normal flight process and the control simulation with failures.展开更多
文章提出了一种面向5G频段和窄带物联网(narrow band internet of things,NB-IoT)的电力物联网频率可重构天线。该天线主要由两个“L”型的辐射枝节、带缺陷地结构的接地面以及用于馈电的微带线组成,辐射枝节和微带线之间分别用PIN二极...文章提出了一种面向5G频段和窄带物联网(narrow band internet of things,NB-IoT)的电力物联网频率可重构天线。该天线主要由两个“L”型的辐射枝节、带缺陷地结构的接地面以及用于馈电的微带线组成,辐射枝节和微带线之间分别用PIN二极管连接。通过调节PIN二极管来改变该天线的表面电流分布,从而实现了良好的可重构性,对改变缺陷地结构来增大电流的路径,使天线获得更宽的带宽。结果表明,当天线的尺寸大小为0.43λ0×0.49λ0,工作在NB-IoT频段(1.85GHz~1.9.0GHz)和5G通信频段(4.4 GHz~5.0 GHz),最大增益分别可为4.5 dBi和5.9 dBi。在实际应用中,该天线可用于认知无线电技术,即在5G通信频段工作状态下探测空闲频谱,并及时切换到NB-IoT工作状态下,从而调整到空闲频率工作,充分满足电网深度监测与智能发电、输电等业务需求。展开更多
Reconfigurability of the electrical network in a shipboard power system （SPS） after its failure is central to the restoration of power supply and improves survivability of an SPS. The navigational process creates a ...Reconfigurability of the electrical network in a shipboard power system （SPS） after its failure is central to the restoration of power supply and improves survivability of an SPS. The navigational process creates a sequence of different operating conditions. The priority of some loads differs in changing operating conditions. After analyzing characteristics of typical SPS, a model was developed used a grade III switchboard and an environmental prioritizing agent （EPA） algorithm. This algorithm was chosen as it is logically and physically decentralized as well as multi-agent oriented. The EPA algorithm was used to decide on the dynamic load priority, then it selected the means to best meet the maximum power supply load. The simulation results showed that higher priority loads were the first to be restored. The system satisfied all necessary constraints, demonstrating the effectiveness and validity of the proposed method.展开更多
基金financial support from the Chang Jiang Scholars Program (51073047)the National Natural Science Foundation of China (51773049)+5 种基金the China Aerospace Science and Technology Corporation-Harbin Institute of Technology Joint Center for Technology Innovation Fund (HIT15-1A01)the Harbin City Science and Technology Projects (2013DB4BP031 and RC2014QN017035)the Natural Science Foundation of Shandong Province of China (ZR2023QE071)the College Students’ Innovation and Entrepreneurship Training Program Projects of Shandong Province (S202211065048)the Scientific Research Foundation of Qingdao University (DC1900009425)the China Postdoctoral Science Foundation (2022TQ0282)
文摘Developing advanced battery-type materials with abundant active sites,high conductivity,versatile morphologies,and hierarchically porous structures is crucial for realizing high-quality hybrid supercapacitors.Herein,heterogeneous FeS@NiS is synthesized by cationic Co doping via surface-structure engineering.The density functional theory(DFT)theoretical calculations are firstly performed to predict the advantages of Co dopant by improving the OH^(−)adsorption properties and adjusting electronic structure,benefiting ions/electron transfer.The dynamic surface evolution is further explored which demonstrates that CoFeS@CoNiS could be quickly reconstructed to Ni(Co)Fe_(2)O_(4)during the charging process,while the unstable structure of the amorphous Ni(Co)Fe_(2)O_(4)results in partial conversion to Ni/Co/FeOOH at high potentials,which contributes to the more reactive active site and good structural stability.Thus,the free-standing electrode reveals excellent electrochemical performance with a superior capacity(335.6 mA h g^(−1),2684 F g^(−1))at 3 A g^(−1).Furthermore,the as-fabricated device shows a quality energy density of 78.1 W h kg^(−1)at a power density of 750 W kg^(−1)and excellent cycle life of 92.1%capacitance retention after 5000 cycles.This work offers a facile strategy to construct versatile morphological structures using electrochemical activation and holds promising applications in energy-related fields.
基金Supported by the National Natural Science Foundation of China (60234010)the Aviation ScienceFoundation of China (05E52031)~~
文摘Aimed at the complex flight control system of a fighter,a kind of robust adaptive control methods using multiple models is presented to make the control system track the given signal under different working conditions and to reconfigure the control law for some structural failures. Firstly,the multiple-model control structure is formed by several linear models and one fuzzy model. In the fuzzy logic way,weights of the multiple-model adaptive controller are obtained. Then,a dynamic structure adaptive neural network is introduced to stabilize the whole system and eliminate the influence caused by the frequent switching. Simulation results show that the control method is effective by demonstrating the normal flight process and the control simulation with failures.
文摘文章提出了一种面向5G频段和窄带物联网(narrow band internet of things,NB-IoT)的电力物联网频率可重构天线。该天线主要由两个“L”型的辐射枝节、带缺陷地结构的接地面以及用于馈电的微带线组成,辐射枝节和微带线之间分别用PIN二极管连接。通过调节PIN二极管来改变该天线的表面电流分布,从而实现了良好的可重构性,对改变缺陷地结构来增大电流的路径,使天线获得更宽的带宽。结果表明,当天线的尺寸大小为0.43λ0×0.49λ0,工作在NB-IoT频段(1.85GHz~1.9.0GHz)和5G通信频段(4.4 GHz~5.0 GHz),最大增益分别可为4.5 dBi和5.9 dBi。在实际应用中,该天线可用于认知无线电技术,即在5G通信频段工作状态下探测空闲频谱,并及时切换到NB-IoT工作状态下,从而调整到空闲频率工作,充分满足电网深度监测与智能发电、输电等业务需求。
基金Supported by the National Natural Science Foundation of China under Grant No.60704004the Fundamental Research Funds for the Central University under Grant No.HEUCFT1005
文摘Reconfigurability of the electrical network in a shipboard power system （SPS） after its failure is central to the restoration of power supply and improves survivability of an SPS. The navigational process creates a sequence of different operating conditions. The priority of some loads differs in changing operating conditions. After analyzing characteristics of typical SPS, a model was developed used a grade III switchboard and an environmental prioritizing agent （EPA） algorithm. This algorithm was chosen as it is logically and physically decentralized as well as multi-agent oriented. The EPA algorithm was used to decide on the dynamic load priority, then it selected the means to best meet the maximum power supply load. The simulation results showed that higher priority loads were the first to be restored. The system satisfied all necessary constraints, demonstrating the effectiveness and validity of the proposed method.
