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Journal of Systems Engineering and Electronics 2023年第4期34卷 894-905页

作者： CHEN Siyu WANG Yong cao rui School of Electronics and Information Engineering Harbin Institute of TechnologyHarbin 150001China

Ultrahigh resolution synthetic aperture radar(SAR)imaging for ship targets is significant in SAR imaging,but it suffers from high frequency vibration of the platform,which will induce defocus into SAR imaging *** this paper,a novel compensation method based on the sinusoidal frequency modulation Fourier-Bessel transform(SFMFBT)is proposed,it can estimate the vibration errors,and the phase shift ambiguity can be avoided via extracting the time frequency ridge *** constructing the corresponding compensation function and combined with the inverse SAR(ISAR)technique,well-focused imaging results can be *** simulation imaging results of ship targets demonstrate the validity of the proposed approach.

关键词： synthetic aperture radar(SAR) high frequency vibration compensation sinusoidal frequency modulation FourierBessel transform(SFMFBT)

Robust optimization of control command for aerospace vehicles with aerodynamic uncertainty

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Chinese Journal of Aeronautics 2022年第12期35卷 226-241页

作者： rui cao Yanbin LIU Yuping LU College of Automated Engineering Nanjing University of Aeronautics and AstronauticsNanjing 210016China

To reduce the design burden of Aerospace Vehicles(ASVs)control systems,this paper proposes a multi-constrained robust trajectory optimization method,which provides a good front-end input for the control *** from the conventional aircraft,some control performance of ASVs is not only related to the model parameters,but also affected by the flight ***,the robust optimization method combines this characteristic of ASVs,sets the control performance as one of the optimization objectives,and considers the influence of parameter *** this method,the polynomial chaos expansion algorithm is used to transform the trajectory optimization problem with uncertain parameters into the equivalent deterministic robust trajectory optimization ***,compared with traditional deterministic trajectory optimization methods to illustrate the effectiveness of proposed control optimization method.

关键词： Aerospace vehicle Multi-objective optimization Polynomial chaos Uncertain systems

Novel method for extraction of ship target with overlaps in SAR image via EM algorithm

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Journal of Systems Engineering and Electronics 2024年第4期35卷 874-887页

作者： cao rui WANG Yong School of Electronics and Information Engineering Harbin Institute of TechnologyHarbin 150001China

The quality of synthetic aperture radar(SAR)image degrades in the case of multiple imaging projection planes(IPPs)and multiple overlapping ship targets,and then the performance of target classification and recognition can be *** addressing this issue,a method for extracting ship targets with overlaps via the expectation maximization(EM)algorithm is ***,the scatterers of ship targets are obtained via the target detection ***,the EM algorithm is applied to extract the scatterers of a single ship target with a single ***,a novel image amplitude estimation approach is pro-posed,with which the radar image of a single target with a sin-gle IPP can be *** proposed method can accom-plish IPP selection and targets separation in the image domain,which can improve the image quality and reserve the target information most *** of simulated and real mea-sured data demonstrate the effectiveness of the proposed method.

关键词： expectation maximization(EM)algorithm image processing imaging projection plane(IPP) overlapping ship tar-get synthetic aperture radar(SAR)

Multiple model predictive control of perching maneuver based on guardian maps

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Chinese Journal of Aeronautics 2022年第5期35卷 347-360页

作者： rui cao Huiwen WAN Zhen HE Yuping LU College of Automated Engineering Nanjing University of Aeronautics and AstronauticsNanjing 210016China

Considering the strong nonlinearity of Unmanned Aerial Vehicles(UAVs)resulting from high Angle of Attack(AOA)and fast maneuvering,we present a multi-model predictive control strategy for UAV maneuvering,which has a small amount of online ***,we divide the maneuver envelope of UAV into several sub-regions on the basis of the gap metric theory.A novel algorithm is then developed to determine the ploytopic model for each *** to this,a Robust Model Predictive Control based on the Idea of Comprehensive optimization(ICE-RMPC)is *** control law is designed offline and optimized online to reduce the computational ***,the ICE-RMPC method is applied to design the controllers of *** addition,to guarantee the stability of whole closed-loop system,a multi-model switching control strategy based on guardian maps is put ***,the tracking performance of proposed control strategy is demonstrated by an illustrative example.

关键词： Guardian maps Model predictive control Multi-Model switching rule Online comprehensive design Perching maneuver

Induced circularly polarized luminescence of perovskite nanocrystals by self-assembly chiral gel

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Nano Research 2023年第1期16卷 1459-1464页

作者： rui cao Xuekang Yang Yong Wang Yin Xiao School of Science Tianjin UniversityTianjin 300350China School of Chemical Engineering and Technology Tianjin UniversityTianjin 300350China National Center for Nanoscience and Technology Beijing 100190China

Perovskites nanocrystals(NCs)with circularly polarized light(CPL)activity have drawn much attention due to the fascinating photoelectric properties of perovskite NCs as well as the abundant applications of CPL in three-dimensional(3D)displays,nonlinear optics,spintronics devices,CPL lasers,and so ***,bio-inspired by life,we designed and synthesized a simple amphiphilic molecule which could self-assemble into chiral gel with helix chirality in non-polar *** co-assembly of the CsPbX3 NCs with the chiral gel,CPL at the first excitation band of CsPbX3 NCs is induced in the whole visible spectrum with a maximum glum of 8.2×10−*** induced CPL arises from the selective CPL-absorption of the CsPbX3 NCs’luminesce by the chiral gel,which provides a facile and practical approach to induce CPL in perovskite NCs and other nanocrystals.

关键词： circularly polarized light(CPL) chiral gel CsPbX3 perovskite nanocrystal selective CPL-absorption

Phase-transfer synthesis of α-Co(OH)_2 and its conversion to CoO for efficient electrocatalytic water oxidation

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Science Bulletin 2017年第9期62卷 626-632页

作者： Dingyi Guo Fangfang Chen Wei Zhang rui cao School of Chemistry and Chemical Engineering Shaanxi Normal University Department of Chemistry Renmin University of China

Water splitting is an attractive way to produce recyclable hydrogen energy resource. The oxygen evolution reaction(OER) is the rate-determine step of water electrolysis. The exploring of low-cost, highly efficient and durable electrocatalysts for OER is thus extremely important. In this work, we developed a facile two-phase protocol to fabricate an α-Co(OH)_2 using sodium oleate as the phase-transfer *** crystallinity and structure of the α-Co(OH)_2 was regulated by heat treatments toward enhanced electrocatalytic OER activity. With the calcination of the as-prepared α-Co(OH)_2 at 200 °C, a networked and well-dispersed CoO nanoparticles were formed. The CoO sample afforded an OER current density of 10 mA cm^(-2) under a low overpotential of 312 mV in a 1 mol L^(-1) KOH aqueous solution. The high activity of the CoO material is believed to be associated with its ultra-small particle size and plentiful open spaces in the material, both of which can provide abundant surface catalytic sites.

关键词： Water oxidation Cobalt oxide Cobalt hydroxide Oxygen evolution reaction Electrocatalysis

Hydrophilic MnO_(2) nanowires coating with o-fluoroaniline for electrocatalytic water oxidation

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Chinese Journal of Structural Chemistry 2023年第8期42卷 31-36页

作者： Lingshuang Qin Wei Zhang rui cao Key Laboratory of Applied Surface and Colloid Chemistry Ministry of Education and School of Chemistry and Chemical EngineeringShaanxi Normal UniversityXi'an710119China

In the active Mn_(4)cao_(5) cluster of the natural water oxidation system,one of the dangling Mn atoms is surrounded by water molecules through coordination and hydrogen *** means that the enrichment of water molecules around the Mn catalysts has a positive effect on the water oxidation *** by nature photosynthesis,the hydrophilic surfaces are believed to be able to capture water molecules to assist water ***,we report MnO_(2)@PFANI nanowires with improved mass transfer efficiency and conductivity for electrocatalytic water *** as-prepared nanowires are synthesized by coating hydrophilic polymers on MnO_(2) *** hydrophilic surface captures water molecule and promotes mass transfer processes,and the conductivity of the polymer can also increase charge transfer *** reach a current density of 10 mA cm^(-2),a low overpotential of 440 mV is required in a 1.0 M KOH solution for the MnO_(2)@PFANI *** hydrophilicity and conductivity are systematically investigated by both physical and electrochemical *** study provides a surface engineering idea for the fabrication of efficient electrocatalysts.

关键词： Electrocatalysis Oxygen evolution reaction MnO_(2) Hydrophilicity Conductivity

Internal Stress Distribution Model of the Magnetomechanical Hysteresis of Fe-Cr-Al Based Alloys

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Journal of Materials Science & Technology 2011年第5期27卷 471-474页

作者： Renrong Lin Wei Jin Mingzhou cao rui Yang Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China

The damping capacities of Fe-13Cr-6AI, Fe-12Cr-1Mo-6AI and Fe-12Cr-1Mn-6Al （at.%） alloys as a function of strain-amplitude tested in a given static load are characterized in the 3-point bending deformation mode. After being modified, Smith-Birchak model is applied to describe the results. It is shown that the modified model agrees with the experimental data much better than the original one. Finally, the influences of stress factors on the damping capacity of the alloys are analyzed.

关键词： Magnetomechanical damping Static load Smith-Birchak model 3-point bending

Oxygen vacancy-rich amorphous FeNi hydroxide nanoclusters as an efficient electrocatalyst for water oxidation

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Journal of Energy Chemistry 2022年第8期31卷 167-173,I0005页

作者： Youhai cao Yang Su Liangliang Xu Xiaohua Yang Zhongkang Han rui cao Gao Li State Key Laboratory of Catalysis Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023LiaoningChina Institute of Quantum and Sustainable Technology(IQST) School of Chemistry and Chemical EngineeringJiangsu UniversityZhenjiang 212013JiangsuChina Multidisciplinary Computational Laboratory Department of Electrical and Biomedical EngineeringHanyang UniversitySeoul 04763South Korea Center for Energy Science and Technology Skolkovo Institute of Science and TechnologySkolkovo Innovation CenterMoscow 143026Russia Stanford Synchrotron Radiation Lightsource SLAC National Accelerator LaboratoryMenlo ParkCA 94025USA

In this work,a one-pot strategy is presented to directly synthesize amorphous Fe_(x)Ni_(y) hydroxide nanoclusters(denoted as ANC-Fe_(x)Ni_(y),<2 nm)with oxygen vacancies induced by ionic *** ANC-Fe_(x)Ni_(y) catalyst presents abundant catalytic sites and high intrinsic *** such,the optimized ANC-Fe_(1)Ni_(2) exhibits high activity in oxygen evolution reaction(OER)with a Tafel slope of 39 m V dec^(–1) and an overpotential of 266 m V at 10 m A cm^(-2).Notably,the optimized ANC-Fe_(1)Ni_(2) shows an extraordinarily large mass activity of 3028 Ag_(FeNi)^(–1) at the overpotential of 300 m V,which is~24-fold of commercial RuO_(2) *** superior activity of these Fe_(x)Ni_(y) hydroxide nanoclusters is ascribed to(i)the amorphous and distorted structure with abundant oxygen vacancies,and(ii)enhanced active site density by downsizing the *** strategy provides a novel route for enhancing OER electrocatalytic performance and highly encouraging for the future application of amorphous metal hydroxides in catalysis.

关键词： Oxygen evolution reaction Hydroxides Amorphous Ni-Fe based nanoclusters Ionic liquids Oxygen vacancies

The Mechanism of Water Oxidation from Mn-Based Heterogeneous Electrocatalysts

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Chinese Journal of Structural Chemistry 2022年第4期41卷 22-33页

作者： Shujiao Yang Lingshuang Qin Wei Zhang rui cao Key Laboratory of Applied Surface and Colloid Chemistry Ministry of EducationSchool of Chemistry and Chemical EngineeringShaanxi Normal UniversityXi'an 710119China

Searching for a renewable energy system is always the goal to fulfill sustainable development for the *** oxidation is considered as a crucial reaction to attain sustainable energy *** by the biological Mn_(4)cao_(5)cluster,considerable effort has been devoted to developing highly efficient Mn-based heterogeneous catalysts and exploring intrinsic mechanism for water *** review begins with describing the structural characteristics of the Mn_(4)Ca O_(5)cluster and the proposed catalytic ***,the structural characteristics of synthetic Mn-based heterogeneous catalyst are summarized,with emphasis on the understanding of reaction mechanisms and the rate-determining ***,the strategy of understanding the catalytic mechanism of Mn-based water oxidation is prospected.

关键词： water oxidation Mn-based electrocatalysts oxygen evolution reaction structure mechanism