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A Special Editor’s Issue on Magnesium Matrix Composites

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Acta Metallurgica Sinica(English Letters) 2024年第3期37卷 389-390页

作者： Xianhua Chen hong yang College of Materials Science and Engineering Chongqing UniversityChongqing 400045China National Engineering Research Center for Mg Alloys Chongqing UniversityChongqing 400045China

Magnesium(Mg)alloys offer distinct advantages as one of the lightest structural *** remarkable weight advantages,being 35%lighter than aluminum alloy and a striking 78%lighter than steel,make them a focal point for research in automotive and aerospace *** emphasis stems from the overarching goal of reducing energy costs and enhancing overall performance[1,2].

关键词： alloy steel alloys

Lattice structure adaptive IIR notch filter based on least square kurtosis

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Journal of Systems Engineering and Electronics 2009年第6期20卷 1188-1192页

作者： Liang hong hong Kang yang Changsheng Coll. of Marine Northwestern Polytechnical Univ. Xi'an 710072 P. R. China

A new variable step-size algorithm for a second-order lattice form structure adaptive infinite impulse response （IIR） notch filter to detection and estimation frequency of sinusoids in Gaussian noises is proposed. Utilizing least square kurtosis of output signals as a cost function, the new gradient-based algorithm to update frequency of the adaptive IIR notch filter and the new variable step-size algorithm are given. The computer simulation results show that the proposed algorithm has better ability in suppressing colored Gaussian noises and better accuracy in estimating parameters at low SNR than previous algorithms.

关键词： adaptive IIR notch filter least square kurtosis variable step-size colored Gaussian noise.

Interception time and uncertainty optimization for tangent-impulse orbit interception problem

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Defence Technology（防务技术） 2022年第3期18卷 418-440页

作者： yang hong Li Xin-hong Ding Wen-zhev Department of Aerospace Science and Technology Space Engineering UniversityNo.1 BaYi RoadHuaiRou DistrictBeijing101416China

The traditional tangent impulse interception problem does not consider the influence of actual ***,by taking the actual state deviation of the interceptor into the orbit design process,an interception orbit that is more robust than the nominal orbit can be ***,we study the minimum time interception problem and the minimum terminal interception error problem under tangent impulse conditions and give an orbit optimization method that considers the interception time and the interception ***,we express the interceptor's transfer time equation as a form of flight path angle,establish a global optimization model for solving the minimum time tangent impulse interception and give a hybrid optimization algorithm based on Augmented Lagrange Genetic Algorithm-Sequential Quadratic Programming(ALGA-SQP).Secondly,we use the universal time equation and Bootstrap resampling technology to calculate the interceptor's terminal error distribution and establish the relevant global optimization model by using the circumscribed cuboid volume of the interceptor's terminal position error ellipsoid as the optimization ***,we combined the above two singleobjective optimization models to establish a global multi-objective optimization model that considers interception time and interception uncertainty and gave a hybrid multi-objective optimization algorithm based on Non-dominated Sorting Genetic Algorithm Ⅱ-Goal Achievement Method(NSGA2-GAM).The simulation example verifies the effectiveness of this method.

关键词： Tangent impulse interception Minimum time Interception uncertainty Multi-objective optimization Hybrid optimization

An Optimal Control Strategy for Multi-UAVs Target Tracking and Cooperative Competition

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IEEE/CAA Journal of Automatica Sinica 2021年第12期8卷 1931-1947页

作者： Yiguo yang Liefa Liao hong yang Shuai Li Jiangxi University of Science and Technology Ganzhou 341000China College of Engineering Swansea UniversitySwansea SA18ENUK

An optimal control strategy of winner-take-all(WTA)model is proposed for target tracking and cooperative competition of multi-UAVs(unmanned aerial vehicles).In this model,firstly,based on the artificial potential field method,the artificial potential field function is improved and the fuzzy control decision is designed to realize the trajectory tracking of dynamic ***,according to the finite-time convergence high-order differentiator,a double closed-loop UAV speed tracking the controller is designed to realize the speed control and tracking of the target tracking *** simulation results show that the designed speed tracking controller has the advantages of fast tracking,high precision,strong stability and avoiding ***,a cooperative competition scheme of multiple UAVs based on WTA is designed to find the minimum control energy from multiple UAVs and realize the optimal control *** analysis and numerical simulation results show that the model has the fast convergence,high control accuracy,strong stability and good robustness.

关键词： Artificial potential field(APF) fuzzy control higher-order differentiator optimal control strategy winner-take-all(WTA)

Artificial Intelligence Applications in the Development of Autonomous Vehicles:A Survey

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IEEE/CAA Journal of Automatica Sinica 2020年第2期7卷 315-329页

作者： Yifang Ma Zhenyu Wang hong yang Lin yang Department of Information Technology and Decision Sciences Old Dominion UniversityNorfolkVA 23529 USA Department of Computational Modeling and Simulation Engineering Old Dominion UniversityNorfolkVA 23529 USA Department of Mechanical and Electrical Engineering Huazhong Agricultural UniversityWuhan 430070China

The advancement of artificial intelligence(AI)has truly stimulated the development and deployment of autonomous vehicles(AVs)in the transportation *** by big data from various sensing devices and advanced computing resources,AI has become an essential component of AVs for perceiving the surrounding environment and making appropriate decision in *** achieve goal of full automation(i.e.,self-driving),it is important to know how AI works in AV *** research have made great efforts in investigating different aspects of applying AI in AV ***,few studies have offered the research community a thorough examination of current practices in implementing AI in ***,this paper aims to shorten the gap by providing a comprehensive survey of key studies in this research ***,it intends to analyze their use of AIs in supporting the primary applications in AVs:1)perception;2)localization and mapping;and 3)decision *** investigates the current practices to understand how AI can be used and what are the challenges and issues associated with their *** on the exploration of current practices and technology advances,this paper further provides insights into potential opportunities regarding the use of AI in conjunction with other emerging technologies:1)high definition maps,big data,and high performance computing;2)augmented reality(AR)/virtual reality(VR)enhanced simulation platform;and 3)5G communication for connected *** paper is expected to offer a quick reference for researchers interested in understanding the use of AI in AV research.

关键词： Artificial intelligence(AI) autonomous vehicles(AVs) deep learning(DL) motion planning perception self-driving

Stability and Hopf bifurcation for a logistic SIR model with a stage -- Structure

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International Journal of Biomathematics 2016年第1期9卷 243-264页

作者： hong yang Department of MathematicsHarbin Institute of Technology (Weihai)Weihai Shandong 264209 P. R. China Department of MathematicsHeilongjiang Bayi Agricultural UniversityDaqing Heilongjiang 163319 P. R. China

A SIR model of epidemiological dynamics with stage-structure and a type of nonlinear incidence rate is considered under the assumption that the susceptible individual satisfy the logistic equation. The global attractivity of the model is studied using Lyapunov functions and LaSalle＇s invariance principle. By the uniform persistence theories, the permanence of the system and the existence of the positive equilibrium are obtained. Moreover, by the normal form theory and the center manifold presented by Hassard, a stability and Hopf bifurcation analysis of the system around positive equilibrium from a local perspective are performed. Numerical simulation is carried out to illustrate our results.

关键词： Epidemiological stage-structure nonlinear incidence rate logistic growth Hopf bifurcation.

Mixed B-site ruddlesden-popper phase Sr_(2)(Ru_(x)Ir_(1-x))O_(4) enables enhanced activity for oxygen evolution reaction

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Journal of Energy Chemistry 2022年第7期31卷 623-629,I0015页

作者： Fangfang Wang Cheng Zhang hong yang Department of Chemical and Biomolecular Engineering University of Illinois at Urbana-ChampaignUrbanaIL 61801USA School of Mechanical and Power Engineering Zhengzhou UniversityZhengzhou 450001HenanChina

Development of high performance electrocatalysts for oxygen evolution reaction (OER) in acidic media remains a challenge for direct water splitting using an ***,Ruddlesden-Popper phase Sr_(2)IrO_(4)was discovered to be an efficient OER catalyst because of its unique structure,which consists of layers of both rock salt and perovskite phases *** this study,we prepared a series of B-site mixed,Ruddlesden-Popper phase of Sr_(2)(Ru_(x)Ir_(1-x))O_(4) and examined their electrocatalytic properties for OER in acidic *** partial substitution of Ru in the B-site of Ruddlesden-Popper phase materials,we achieved much enhanced OER performance for this series of Sr_(2)(Ru_(x)Ir_(1-x))O_(4)electrocatalysts,among which Sr_(2)(Ru_(0.5)Ir_(0.5))O_(4)exhibited the best catalytic activity with a current density of 8.06 m A/cm^(2) at 1.55 V and a Tafel slope of 47 m V/*** current density is three times higher than that of Sr_(2)Ir O_(4).The B-site mixed Sr_(2)(Ru_(0.5)Ir_(0.5))O_(4)retained good stability in acidic conditions for>24 h at 10 m A/cm^(2).A range of techniques were used to characterize the crystal and electronic structures of the Sr_(2)(Ru_(x)Ir_(1-x))O_(4)*** data indicate that the improved OER performance can be correlated to the formation of high level of hydroxyl groups and the enhanced overlap between Ir/Ru 4d and O_(2)p orbitals,revealing a new way for the design of efficient OER electrocatalysts by regulating their composition and electronic structures.

关键词： Water splitting OER Electrocatalyst Ruddlesden-Popper Strontium ruthenium iridium oxide

Corrosion resistance behavior of gradient microstructure induced by punching deformation and recovery treatment on cupronickel alloy surface

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Rare Metals 2017年第12期36卷 971-976页

作者： Xiang-yang Mao Hao Chen hong-Yan yang Yao Yao hong-Xing Wang Jiangsu Key Laboratory of Advanced Structural Materials and Application Technology School of Materials EngineeringNanjing Institute of Technology Nanjing 211167 China

In this study, the gradient grain induced by punching deformation and recovery treatment on a cupronickel alloy surface sample were investigated, and their effects on corrosion resistance were measured by atom force microscopy(AFM), X-ray diffraction(XRD),electrochemical measurement, electron work function(EWF), and contact electrical resistance(CER). The cupronickel alloy surface experienced punching deformation for 60 min and recovery at 300 ℃ for 1 h to produce gradient surface. The grain size measured by XRD is bigger than that measured by AFM, due to X-ray intensity of95 % produced at the depth of 12-20 μm for the crystal planes of(111),(200), and(220). The gradient grain surface, compared to the original surface, shows a 13.7-fold decrease in passivation current density(i), and corrosion potential(Ec) increases by approximately 9.8 %. These results are attributable to the increase in EWF and formation of passivation film with better adhesion and compactness after treatment.

关键词： Gradient grain Corrosion resistance Electron work function Punching deformation

PtAu Bimetallic Heteronanostructures Made by Post-Synthesis Modification of Pt-on-Au Nanoparticles

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Nano Research 2009年第5期2卷 406-415页

作者： Zhenmeng Peng hong yang Department of Chemical Engineering University of RochesterGavett Hall 206RochesterNY 14627USA

Bimetallic PtAu heteronanostructures have been synthesized from Pt-on-Au nanoparticles,which were made from platinum acetylacetonate and gold *** the Pt-on-Au nanoparticles as precursors,Pt-surface rich PtAu bimetallic heteronanostructures can be produced through controlled thermal treatments,as confirmed by field emission high-resolution transmission electron microscopy(HR-TEM)and elemental mapping using a high-angle annular dark-field scanning transmission electron microscope(HAADF-STEM).Oxidation of formic acid was used as a model reaction to demonstrate the effects of varying composition and surface structure on the catalytic performance of PtAu bimetallic *** voltammetry(CV)showed that these carbon-supported PtAu heteronanostructures were much more active than platinum in catalyzing the oxidation of formic acid,judging by the mass current *** results showed that post-synthesis modification can be a very useful approach to the control of composition distributions in alloy nanostructures.

关键词： Nanostructure alloy platinum gold formic acid oxidation electrocatalyst polymer electrolyte membrane fuel cell(PEMFC)