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Data-driven active vibration control for helicopter with trailing-edge flaps using adaptive dynamic programming

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Chinese Journal of Aeronautics 2024年第6期37卷 151-166页

作者： Yu CHEN Qun ZONG Xiuyun ZHANG Jinna LI school of Electrical and information Engineering Tianjin UniversityTianjin 300072China school of information and Control Engineering Liaoning Petrochemical UniversityFushun 113001China

The helicopter Trailing-Edge Flaps(TEFs)technology is one of the recent hot topics in morphing wing *** employing controlled deflection,TEFs can effectively reduce the vibration level of ***,designing specific vibration reduction control methods for the helicopters equipped with trailing-edge flaps is of significant practical *** paper studies the optimal control problem for helicopter-vibration systems with TEFs under the framework of adaptive dynamic programming combined with Reinforcement Learning(RL).Time-delay and disturbances,caused by complexity of helicopter dynamics,inevitably deteriorate the control performance of vibration *** solve this problem,a zero-sum game formulation with a linear quadratic form for reducing vibration of helicopter systems is presented with a virtual *** this context,an off-policy reinforcement learning algorithm is developed to determine the optimal control *** algorithm utilizes only vertical vibration load data to achieve a policy that reduces vibration,attains Nash equilibrium,and addresses disturbances while compensating for time-delay without knowledge of the dynamics of the helicopter *** effectiveness of the proposed method is demonstrated in a virtual platform.

关键词： Active control Adaptive dynamic program-ming Helicopter rotor Vibration control Zero-sum game

Weighted Linear Loss Large Margin Distribution Machine for Pattern Classification

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Chinese Journal of Electronics 2024年第3期33卷 753-765页

作者： Ling LIU Maoxiang CHU Rongfen GONG Liming LIU Yonghui YANG school of Electronic and information Engineering University of Science and Technology Liaoning

Compared with support vector machine,large margin distribution machine(LDM) has better generalization *** central idea of LDM is to maximize the margin mean and minimize the margin variance *** the computational complexity of LDM is *** order to reduce the computational complexity of LDM,a weighted linear loss LDM(WLLDM) is *** framework of WLLDM is built based on LDM and the weighted linear *** weighted linear loss is adopted instead of the hinge loss in *** modification can transform the quadratic programming problem into a simple linear equation,resulting in lower computational ***,WLLDM has the potential to deal with large-scale *** WLLDM is similar in principle to the LDM algorithm,which can optimize the margin distribution and achieve better generalization *** WLLDM algorithm is compared with other models by conducting experiments on different *** results show that the proposed WLLDM has better generalization performance and faster training speed.

关键词： Training Support vector machines Pattern classification Transforms Fasteners Mathematical models Vectors

Color Image Compression and Encryption Algorithm Based on 2D Compressed Sensing and Hyperchaotic System

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Computers, Materials & Continua 2024年第2期78卷 1977-1993页

作者： Zhiqing Dong Zhao Zhang Hongyan Zhou Xuebo Chen school of Computer Science and Software Engineering University of Science and Technology LiaoningAnshan114051China school of Electronic and information Engineering University of Science and Technology LiaoningAnshan114051China

With the advent of the information security era,it is necessary to guarantee the privacy,accuracy,and dependable transfer of *** study presents a new approach to the encryption and compression of color *** is predicated on 2D compressed sensing(CS)and the hyperchaotic ***,an optimized Arnold scrambling algorithm is applied to the initial color images to ensure strong ***,the processed images are con-currently encrypted and compressed using 2D *** them,chaotic sequences replace traditional random measurement matrices to increase the system’s ***,the processed images are re-encrypted using a combination of permutation and diffusion *** addition,the 2D projected gradient with an embedding decryption(2DPG-ED)algorithm is used to reconstruct *** with the traditional reconstruction algorithm,the 2DPG-ED algorithm can improve security and reduce computational ***,it has better *** experimental outcome and the performance analysis indicate that this algorithm can withstand malicious attacks and prove the method is effective.

关键词： Image encryption image compression hyperchaotic system compressed sensing

Reaction behavior of MgO refractory with high-Mn and high-Al steel

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Journal of Iron and Steel Research International 2024年第6期31卷 1389-1398页

作者： Ling-zhong Kong Lin Zu Jie Yang Xi-min Zang Xin Yang Ming Kang school of Materials and Metallurgy University of Science and Technology LiaoningAnshan 114051LiaoningChina

To understand the mechanism of the interfacial reaction between high-Mn and high-Al steel and MgO refractory,a series of laboratory experiments as well as thermodynamic calculations were *** effects of Mn and Al contents in the steel and the reaction time on the interfacial reaction were *** was observed that the erosion of the MgO refractory is caused by the reaction of Al and Mn in the steel with MgO in the refractory,which would lead to the formation of(Mn,Mg)O·Al_(2)O_(3) spinel and(Mn,Mg)O solid *** formation mechanism of the spinel and solid solution is as *** Al in the steel firstly reacts with MgO in the refractory to generate MgO·Al_(2)O_(3) spinel,and then,the spinel reacts with Mn in the steel to form(Mn,Mg)O·Al_(2)O_(3) ***,the MnO in the spinel reacts with the MgO in the inner refractory to form(Mn,Mg)O solid *** addition,only(Mn,Mg)O·Al_(2)O_(3) spinel is present in the interfacial reaction layer of the refractory when the Al content in the steel is sufficient.

关键词： High-Mn high-Al steel MgO refractory Reaction behavior Spinel

Sufficient Conditions for Amalgamated 3-Manifolds to be ∂-Irreducible

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Chinese Annals of Mathematics,Series B 2024年第2期45卷 161-172页

作者： Bing FANG Fengchun LEI Liang LIANG school of Mathematical Sciences Dalian University of TechnologyDalian 116024LiaoningChina school of Mathematics Liaoning Normal UniversityDalian 116029LiaoningChina

In this paper,the authors give some sufficient conditions for an amalgamated 3-manifold along a compact connected surface F with boundary to be ∂-irreducible in terms of distances between some kinds of vertex subsets ... 详细信息

关键词： ∂-Irreducibility Irreducibility Amalgamated 3-manifold Curve complex Arc complex

Real-Time Energy Management for Net-Zero Power Systems Based on Shared Energy Storage

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Journal of Modern Power Systems and Clean Energy 2024年第2期12卷 371-380页

作者： Pengbo Du Bonan Huang Ziming Liu Chao Yang Qiuye Sun school of information Science and Engineering Northeastern UniversityShenyang 110004China information and Communication Branch State Grid Liaoning Electric Power Company Ltd.Shenyang 110004China IEEE

Battery energy storage systems(BESSs)serve a crucial role in balancing energy fluctuations and reducing carbon emissions in net-zero power ***,the efficiency and cost performance have remained significant challenges,which hinders the widespread adoption and development of *** address these challenges,this paper proposes a real-time energy management scheme that considers the involvement of prosumers to support net-zero power *** scheme is based on two shared energy storage models,referred to as energy storage sale model and power line lease *** energy storage sale model balances real-time power deviations by energy interaction with the goal of minimizing system costs while generating revenue for shared energy storage providers(ESPs).Additionally,power line lease model supports peer-to-peer(P2P)power trading among prosumers through the power lines laid by ESPs to connect each *** model allows ESP to earn profits from the use of power lines while balancing power deviations and better consuming renewable *** results validate the effectiveness of the proposed scheme,ensuring stable power supply for net-zero power systems and providing benefits for both the ESP and prosumers.

关键词： Shared energy storage energy storage provider(ESP) energy management peer-to-peer(P2P)trading net-zero power system

The role of strain in oxygen evolution reaction

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Journal of Energy Chemistry 2024年第6期93卷 322-344,I0009页

作者： Zihang Feng Chuanlin Dai Zhe Zhang Xuefei Lei Wenning Mu Rui Guo Xuanwen Liu Junhua You school of Materials Science and Engineering Northeastern UniversityShenyang 110819LiaoningChina school of Materials Science and Technology Shenyang University of TechnologyShenyang 110870LiaoningChina

The oxygen evolution reaction(OER)is a crucial step in metal-air batteries and water splitting technologies,playing a significant role in the efficiency and achievable heights of these two ***,the OER is a four-step,four-electron reaction,and its slow kinetics result in high overpotentials,posing a *** address this issue,numerous strategies involving modified catalysts have been proposed and proven to be highly *** these strategies,the introduction of strain has been widely reported because it is generally believed to effectively regulate the electronic structure of metal sites and alter the adsorption energy of catalyst surfaces with reaction ***,strain has many other effects that are not well known,making it an important yet unexplored *** on this,this review provides a detailed introduction to the various roles of strain in *** better explain these roles,the review also presents the definition of strain and elucidates the potential mechanisms of strain in OER based on the d-band center theory and adsorption volcano ***,the review showcases various ways of introducing strain in OER through examples reported in the latest literature,aiming to provide a comprehensive perspective for the development of strain ***,the review analyzes the appropriate proportion of strain introduction,compares compressive and tensile strain,and examines the impact of strain on *** the review offers prospects for future research directions in this emerging field.

关键词： Oxygen evolution reaction Strain generation Tensile strain Compressive strain Strain mechanism Strain effects

Impurity formation mechanism of silicon carbide crystals smelted by Acheson process

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Journal of Iron and Steel Research International 2024年第6期31卷 1367-1375页

作者： Dong Feng Hong-qiang Ru Xu-dong Luo Jie-gang You Ling Zhang school of Materials and Metallurgy University of Science and Technology LiaoningAnshan 114051LiaoningChina Key Laboratory for Anisotropy and Texture of Materials(Ministry of Education) Institute of Advanced CeramicsSchool of Materials Science and EngineeringNortheastern UniversityShenyang 110819LiaoningChina liaoning Institute of Science and Technology Benxi 117004LiaoningChina

In order to further promote the application of SiC refractories in modern steel metallurgy,the occurrence forms and formation mechanism of impurities in SiC crystals smelted by Acheson process were *** techniques of inductively coupled plasma-atomic emission spectrometry,X-ray diffraction,and scanning electron microscopy were combined to examine the types and occurrence forms of impurities in smelted SiC *** results showed that the main impurities in the SiC are free Si,free C,oxides(CaO·Al_(2)O_(3)·2SiO_(2),3Al_(2)O_(3)·2SiO_(2),CaO·SiO_(2) and SiO_(2))and alloy phases(Fe_(x)Si_(y),Fe_(x)Si_(y)Ti_(z) and Fe_(x)Al_(y)Si_(z)).The formation process of impurities during the smelting of SiC can be described as follows:At high temperature,the SiO_(2) and Fe,Ti related oxide impurities present in the raw materials are reduced to Si,Fe,and Ti metal *** the reduction process,the free Si,Fe_(x)Si_(y) and Fe_(x)Si_(y)Ti_(z) are precipitated from the melt during *** Si primarily exists in aggregated form within the SiC crystal,while the alloy phase is predominantly found at the interface between SiC and free Si,with Fe_(x)Si_(y)Ti_(z) embedded within *** the end of the cooling process,other impurity oxides such as Al_(2)O_(3),CaO,and some unreduced SiO_(2) solidify to form calcium-aluminum-silicate glass phases,predominantly located between SiC *** remaining C from the reaction is mainly dispersed as free C within the SiC crystal and at the interface between SiC and free Si.

关键词： Impurity element Formation mechanism Smelted SiC crystal SiC refractory Occurrence form

Near infrared emissions from both high efficient quantum cutting (173%) and nearly-pure-color upconversion in NaY(WO_(4))_(2):Er^(3+)/Yb^(3+) with thermal management capability for silicon-based solar cells

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Light(Science & Applications) 2024年第1期13卷 113-126页

作者： Duan Gao Baojiu Chen Xuezhu Sha Yuhang Zhang Xin Chen Li Wang Xizhen Zhang Jinsu Zhang Yongze Cao Yichao Wang Lei Li Xiangping Li Sai Xu Hongquan Yu Lihong Cheng school of Science Dalian Maritime UniversityDalian 116026 LiaoningChina

Raising photoelectric conversion efficiency and enhancing heat management are two critical concerns for siliconbased solar *** this work,efficient Yb^(3+) infrared emissions from both quantum cutting and upconversion were demonstrated by adjusting Er^(3+) and Yb^(3+) concentrations,and thermo-manage-applicable temperature sensing based on the luminescence intensity ratio of two super-low thermal quenching levels was discovered in an Er^(3+)/Yb^(3+) codoped tungstate *** quantum cutting mechanism was clearly decrypted as a two-step energy transfer process from Er^(3+) to Yb^(3+).The two-step energy transfer efficiencies,the radiative and nonradiative transition rates of all interested 4 f levels of Er^(3+) in NaY(WO_(4))_(2) were confirmed in the framework of Föster-Dexter theory,Judd-Ofelt theory,and energy gap law,and based on these obtained efficiencies and rates the quantum cutting efficiency was furthermore determined to be as high as 173%in NaY(WO_(4))_(2):5 mol%Er^(3+)/50 mol%Yb^(3+) *** and nearly pure infrared upconversion emission of Yb3+under 1550 nm excitation was achieved in Er^(3+)/Yb^(3+)co-doped NaY(WO_(4))_(2) by adjusting Yb^(3+) doping *** Yb^(3+) induced infrared upconversion emission enhancement was attributed to the efficient energy transfer ^(4)I_(11/2)(Er^(3+))+^(2)F_(7/2)(Yb^(3+))→^(4)I_(15/2)(Er^(3+))+^(2)F_(5/2)(Yb^(3+))and large nonradiative relaxation rate of ^(4)I_(9/2).Analysis on the temperature sensing indicated that the NaY(WO_(4))_(2):Er^(3+)/Yb^(3+)serves well the solar cells as thermos-managing ***,it was confirmed that the fluorescence thermal quenching of ^(2)H_(11/2)/^(4)S_(3/2) was caused by the nonradiative relaxation of ^(4)S_(3/2).All the obtained results suggest that NaY(WO_(4))_(2):Er^(3+)/Yb^(3+) is an excellent material for silicon-based solar cells to improve photoelectric conversion efficiency and thermal management.

关键词： quantum thermal relaxation