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Acta Mathematicae Applicatae Sinica 2024年第4期40卷 1111-1126页

作者： Liang-qiang zhou Fang-qi CHEN School of Mathematics Nanjing University of Aeronautics and AstronauticsNanjing 210016China

Chaotic dynamics of the van der Pol-Duffing oscillator subjected to periodic external and parametric excitations with delayed feedbacks are investigated both analytically and numerically in this *** the Melnikov method,the critical value of chaos arising from homoclinic or heteroclinic intersections is derived *** feature of the critical curves separating chaotic and non-chaotic regions on the excitation frequency and the time delay is investigated analytically in *** monotonicity of the critical value to the excitation frequency and time delay is obtained *** is presented that there may exist a special frequency for this *** this frequency,chaos in the sense of Melnikov may not occur for any excitation *** also exists a uncontrollable time delay with which chaos always occurs for this *** simulations are carried out to verify the chaos threshold obtained by the analytical method.

关键词： Van der Pol-Duffing oscillator time delay chaos parametric excitation Melnikov method

Predicting the International Roughness Index of JPCP and CRCP Rigid Pavement:A Random Forest(RF)Model Hybridized with Modified Beetle Antennae Search(MBAS)for Higher Accuracy

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Computer Modeling in Engineering & Sciences 2024年第5期139卷 1557-1582页

作者： zhou Ji Mengmeng zhou qiang Wang Jiandong Huang College of Civil and Environmental Engineering Hunan University of Science and EngineeringYongzhou425006China School of Mines China University of Mining and TechnologyXuzhou221116China School of Civil Engineering Guangzhou UniversityGuangzhou510006China

To improve the prediction accuracy of the International Roughness Index(IRI)of Jointed PlainConcrete Pavements(JPCP)and Continuously Reinforced Concrete Pavements(CRCP),a machine learning approach is developed in this study for the modelling,combining an improved Beetle Antennae Search(MBAS)algorithm and Random Forest(RF)*** 10-fold cross-validation was applied to verify the reliability and accuracy of the model proposed in this *** importance scores of all input variables on the IRI of JPCP and CRCP were analysed as *** results by the comparative analysis showed the prediction accuracy of the IRI of the newly developed MBAS and RF hybrid machine learning model(RF-MBAS)in this study is higher,indicated by the RMSE and R values of 0.2732 and 0.9476 for the JPCP as well as the RMSE and R values of 0.1863 and 0.9182 for the *** accuracy of this obtained result far exceeds that of the IRI prediction model used in the traditional Mechanistic-Empirical Pavement Design Guide(MEPDG),indicating the great potential of this developed *** importance analysis showed that the IRI of JPCP and CRCP was proportional to the corresponding input variables in this study,including the total joint faulting cumulated per KM(TFAULT),percent subgrade material passing the 0.075-mm Sieve(P_(200))and pavement surface area with flexible and rigid patching(all Severities)(PATCH)which scored higher.

关键词： Cement pavement JPCP CRCP RF-MBAS IRI

Strain and carrier-induced coexistence of topologically insulating and superconducting phase in iodized Si（111） films

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Nano Research 2016年第6期9卷 1578-1589页

作者： Jian zhou QianWang qiang Sun Puru Jena Physics Department Virginia Commonwealth University Richmond VA 23284 USA Center for Applied Physics and Technology College of Engineering Peking University Beijing 100871 China Department of Materials Science and Engineering College of Engineering Peking University Beijing 100871 China

The importance of silicon in modem electronic devices has led to considerable interest in exploring the unconventional electronic properties of Si-based materials for future applications in spintronics and quantum computing. Here, using density functional theory, we present the results of a systematic study of the effect of strain on Si（lll） thin films whose surfaces are functionalized with iodine. Films with an odd number of layers under biaxial strain are found to undergo a phase transition from a normal insulator to a topological insulator and ultimately to a metal. The spin-orbit coupling-induced topologically nontrivial band gap at the F point is found to be as large as 0.50 eV, which not only surpasses that of other Si-based topological materials, it is also large enough for practical realization of quantum spin Hall states at room temperature. No such nontrivial states are found in films for such a strain-induced transition with an even number of layers. Mechanisms are illustrated by a tight-binding model composed of s, px, and py orbitals. Equally important, we predict that iodized silicene, when stretched and hole-doped, would be a phonon-mediated super- conductor with a critical temperature of 9.2 K. This coexistence of a topological insulator and a superconducting phase in a single material is unusual; it has the potential for applications in electronic circuits and for the realization of Majorana fermions in quantum computations.

关键词： Si(lll) film topological insulator phonon-mediatedsuperconductor strain effects spin-orbit coupling

1+1>2: Learning from the interfacial modulation on single-atom electrocatalysts to design dual-atom electrocatalysts for dinitrogen reduction

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Green Energy & Environment 2023年第6期8卷 1753-1763页

作者： qiang zhou Feng Gong Yunlong Xie Rui Xiao College of Materials Xiamen UniversityXiamen361005China Key Laboratory of Energy Thermal Conversion and Control of Ministry of Education School of Energy and EnvironmentSoutheast UniversityNanjing211189JiangsuChina Institute for Advanced Materials Hubei Normal UniversityHuangshi435002China

Developing efficient electrocatalysts for converting dinitrogen to ammonia through electrocatalysis is of significance to the decentralized ammonia production. Here, through high-throughput density functional theory calculations, we demonstrated that the interfacial modulation of hexagonal boron nitride/graphene(hBN-graphene) could sufficiently improve the catalytic activity of the single transition metal atom catalysts for nitrogen reduction reaction(NRR). It was revealed that Re@hBN-graphene and Os@hBN-graphene possessed remarkable NRR catalytic activity with low limiting potentials of 0.29 V and 0.33 V, respectively. Furthermore, the mechanism of the enhanced catalytic activity was investigated based on various descriptors of the adsorption energies of intermediates, where the synergistic effect of hBN and graphene in the hybrid substrate was found to play a key role. Motivated by the synergistic effect of hybrid substrate in single-atom catalysts, a novel strategy was proposed to efficiently design dual-atom catalysts by integrating the merits of both metal components. The as-designed dual-atom catalyst Fe-Mo@hBN exhibited more excellent NRR catalytic performance with a limiting potential of 0.17 V, manifesting the solidity of the design strategy. Our findings open new avenues for the search of heterostructure substrates for single-atom catalysts and the efficient design of dualatom catalysts for NRR.

关键词： Nitrogen reduction reaction Boron nitride Graphene High throughput Descriptor Density functional theory Single-atom catalyst Dual-atom catalyst

Physiological response of locusts to eye stimulation by spectral illumination for phototactic pest control

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International Journal of Agricultural and Biological Engineering 2016年第2期9卷 186-194页

作者： Liu Qihang zhou qiang Henan Institute of Science and Technology Xinxiang 453003China College of Engineering China Agricultural UniversityBeijing 100083China

To provide theoretical support for study of locust phototactic vision nature,the locust phototactic physiology and visual spectrum effects were investigated by stimulating the visual system using light from an AvaSpec fiber-optic spectrometer and Flir thermal imaging *** light stimulated the locust visual system,the biological photoelectric transformation effect of the visual system caused by photon energy,presented with the higher physiological temperature on the forehead,as tested by the Flir thermal *** stimulation with light,the different absorption degrees of the vision system on the spectral photons,as tested by the AvaSpec spectrometer,showed that the phototactic response to light had the simultaneous requirements of lighting intensity and *** absorbing differences of spectral photons by the vision system demonstrated the absorption selectivity under light stimulation,as exhibited by the sensitive absorption of spectral energy at 430 nm,545 nm and 615 ***,the higher forehead temperature increment indicated and induced the stronger physiology activity which was the reason that causing the good phototactic response degree of locusts with 30 min light stimulation,and the adaption time was about 60 ***,only when the visual reaction effect was stimulated to absorb sensitive spectral energy and generate the physiological exciting response could cause the phototactic behavior.

关键词： phototactic pest control physiological response Locusta migratoria spectral illumination phototactic vision spectrum absorption light simulation

Nepenthes pitchers:surface structure,physical property,anti-attachment function and potential application in mechanical controlling plague locust

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Chinese Science Bulletin 2014年第21期59卷 2513-2523页

作者： Lixin Wang qiang zhou College of Mechanical Engineering Hebei University of Science and Technology College of Engineering China Agricultural University

Pitchers plants of Nepenthes specie growing in infertile habitats have developed highly specialized apparatus for trapping and digesting arthropods to obtain sufficient growing *** pitchers are generally recognized by several distinguishably morphological zones,and different districts exhibit distinct functions in prey capturing,combined effect of the several zones results in great trapping *** prey ability of Nepenthes pitchers potentially inspires an idea for biomimetic development of slippery trapping plate used in controlling agricultural pests,especially plague *** this paper,we reviewed the recent researches of Nepenthes pitchers,including surface structures,physical properties,and antiattachment *** from this,combined with our latest studies on mechanical controlling plague locust,the potential application of Nepenthes pitchers as establishing biomimetic models utilized in creating trapping plate was addressed,and several corresponding aspects requiring to be paid attention to in near future were also highlighted.

关键词：机械控制表面结构猪笼草物理性质蝗虫应用鼠疫附着

Rational Design of Biomolecules/Polymer Hybrids by Reversible Deactivation Radical Polymerization (RDRP) for Biomedical Applications

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Chinese Journal of Polymer Science 2021年第9期39卷 1093-1109页

作者： Jie zhou Xiao-Yuan Zhang Zhi-qiang Su State Key Laboratory of Chemical Resource Engineering Beijing Key Laboratory of Advanced Functional Polymer CompositesBeijing University of Chemical TechnologyBeijing 100029China

Hybrids,produced by hybridization of proteins,peptides,DNA,and other new biomolecules with polymers,often have unique functional *** properties,such as biocompatibility,stability and specificity,lead to various smart *** review mainly introduces biomolecule polymer hybrid materials by reversible deactivation radical polymerization(RDRP),emphasizing reverse addition-fragmentation chain transfer(RAFT)polymerization,and nitroxide mediated polymerization(NMP).It includes the methods of RDRP to improve the biocompatibility of biomedical materials and organisms by surface *** key to the current synthesis of biomolecule polymer hybrids is to control ***,this review describes several different kinds of biomolecule polymer hybrid materials and their applications in the biomedical *** progresses provide ideas for the investigation of biodegradable and highly bioactive biomedical soft tissue *** research hotspots of nanotechnology in biomedical fields are controlled drug release materials and gene therapy carrier *** showed that RDRP method could improve the therapeutic effect and reduce the dosage and side effects of the ***,by means of RDRP,the original materials can be modified to develop intelligent polymer materials as membrane materials with selective permeability and surface modification.

关键词： Biomolecule-polymer hybrids RDRP Biomedical applications Drug release Nanotechnology

Modulation of driving signals in flow control over an airfoil with synthetic jet

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Chinese Journal of Aeronautics 2020年第12期33卷 3138-3148页

作者： Zhiyong LIU Zhenbing LUO qiang LIU Yan zhou College of Aerospace Science and Engineering National University of Defense TechnologyChangsha 410073China China Aerodynamics Research and Development Center Mianyang 621000China

A new skill of modulating driving signals of a synthetic jet with low frequency is introduced to enhance the control *** on dynamic mesh technique,the effect of flow control over a NACA0015 airfoil with a Synthetic Jet Actuator(SJA)has been *** SJA is located at x/c=10%,and two jet injection angles of 90°and 30°have been *** structures indicate that modulation with low frequency can reduce the dissipation rate of vortices after they shed off the *** aerodynamic performance of the airfoil could be *** the injection angle of 90°,modulation can increase the control authority of the *** to the unmodulated case,increment of lift-to-drag ratio is up to 15%.The modulating frequency corresponding to the largest increment is F_(M)^(+)≈*** the injection angle of 30°,improvement of aerodynamic forces positively relates to momentum coefficient of the *** to the decrease of effective momentum,modulation degrades the effect of flow *** opposite responses to modulation are believed to have a relationship with the variation of primary control *** jet injection angle varies from 90°to 30°,the primary mechanism changes from the interaction of vortices and waves to the direct momentum *** skill of modulation of driving signals is very useful for applications of SJA.

关键词： Airfoil Flow control Injection angle Modulation Momentum coefficient Synthetic jet

Integrated Energy Production Unit: An Innovative Concept and Design for Energy Transition Toward Low-carbon Development

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CSEE Journal of Power and Energy Systems 2021年第6期7卷 1133-1139页

作者： Xiaoxin zhou qiang Zhao Yuqiong Zhang Li Sun China Electric Power Research Institute Beijing 100192China the Key Lab of Energy Thermal Conversion and Control of the Ministry of Education School of Energy and EnvironmentSoutheast UniversityNanjing 210089China

To achieve the goals of emission peak and carbon neutrality,significant effort is invested to accelerate the energy transition,with a focus on the development and utilization of renewable energy,as well as the upgrading of conventional *** this context,this paper proposes an innovative concept,known as the integrated energy production unit(IEPU),providing a variety of energy products and flexible adjustment functions for power systems with high penetration of non-hydro renewable *** the IEPU framework,a photovoltaic(PV)power plant is installed to produce electricity;CO_(2) capture technology is applied to the existing coal-fired power plant with biomass *** generated CO_(2) is used to synthesize methane or methanol with hydrogen through ***,the operational principle and advantages of this concept are ***,a simplified model is built to provide an optimal configuration scheme of equipment ***,the potential contribution of IEPU to the operational flexibility of the power system is also analyzed.

关键词： CO_(2)capture flexibility hydrogen production from renewables integrated energy production unit methane/methanol

Active control of flow past an elliptic cylinder using an artificial neural network trained by deep reinforcement learning

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Applied Mathematics and Mechanics(English Edition) 2022年第12期43卷 1921-1934页

作者： Bofu WANG qiang WANG Quan zhou Yulu LIU Shanghai Key Laboratory of Mechanics in Energy Engineering Shanghai Institute of Applied Mathematics and MechanicsSchool of Mechanics and Engineering ScienceShanghai UniversityShanghai 200072China Shanghai Frontiers Science Base for Mechanoinfomatic Shanghai UniversityShanghai 200072China School of Science Shanghai Institute of TechnologyShanghai 201418China

The active control of flow past an elliptical cylinder using the deep reinforcement learning(DRL)method is *** axis ratio of the elliptical cylinderΓvaries from 1.2 to 2.0,and four angles of attackα=0°,15°,30°,and 45°are taken into consideration for a fixed Reynolds number Re=*** mass flow rates of two synthetic jets imposed on different positions of the cylinderθ1andθ2are trained to control the *** optimal jet placement that achieves the highest drag reduction is determined for each *** a low axis ratio ellipse,i.e.,Γ=1.2,the controlled results atα=0°are similar to those for a circular cylinder with control jets applied atθ1=90°andθ2=270°.It is found that either applying the jets asymmetrically or increasing the angle of attack can achieve a higher drag reduction rate,which,however,is accompanied by increased *** control jets elongate the vortex shedding,and reduce the pressure ***,the flow topology is modified at a high angle of *** an ellipse with a relatively higher axis ratio,i.e.,Γ1.6,the drag reduction is achieved for all the angles of attack *** larger the angle of attack is,the higher the drag reduction ratio *** increased fluctuation in the drag coefficient under control is encountered,regardless of the position of the control *** control jets modify the flow topology by inducing an external vortex near the wall,causing the drag *** results suggest that the DRL can learn an active control strategy for the present configuration.

关键词： drag reduction deep reinforcement learning(DRL) elliptical cylinder active control