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Science China(Technological Sciences) 2024年第1期67卷 209-220页

作者： zhu guoliang LIU KeXin GU HaiBo LÜJinHu School of Automation Science and Electrical Engineering Beihang UniversityBeijing 100191China Zhongguancun Laboratory Beijing 100094China

This paper investigates the consensus-based formation control problem for multi-agent systems with unknown nonlinear dynamics.To achieve the desired formation,we propose two formation controllers to achieve the desired formation,one based on system states and the other on system outputs.The proposed controllers utilize adaptive gains to avoid global information and neural networks to estimate and compensate for nonlinearities.The proposed event-triggered schemes avoid continuous communication among agents and exclude the Zeno behavior.Stability analysis reveals that formation errors are bounded,and numerical simulations are used to validate the effectiveness of the proposed approaches.

关键词： formation control neural network adaptive control event-triggered communication multi-agent systems

Dislocation glide and mechanical twinning in a ductile VNbTi medium entropy alloy

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Journal of Materials Science & Technology 2022年第15期110卷 210-215页

作者： Mingxu Wu Shubin Wang Fei Xiao Guoliang Zhu Chao Yang Da Shu Baode Sun Shanghai Key Lab of Advanced High-temperature Materials and Precision Forming and State Key Lab of Metal Matrix Composites School of Materials Science and EngineeringShanghai Jiao Tong UniversityShanghai 200240China

An equiatomic VNbTi medium-entropy alloy with outstanding tensile properties and unique deformation behavior is reported.The screw dislocation glide,deformation twinning,and dislocation accumulation induced kink bands are identified as three deformation mechanisms that contribute to a large elongation above 20%.The{112}twins are activated at the beginning of the yield stage accompanied by sudden stress-drop and pronounced acoustic emission.Dislocations dominate subsequent tensile deformation,and the prevalent multiplanar dislocation slip promotes the formation of complex dislocation configurations(e.g.,debris,dipoles,and loops)and dense dislocation networks.The twin bands and kink bands can further impede the dislocation motion meanwhile effectively alleviate stress concentration.The synergistic activation of these deformation mechanisms provides new opportunities to design ductile refractory medium-and high-entropy alloys.

关键词： Medium-entropy alloy Mechanical twinning Screw dislocation Multiplanar slip Tensile deformation

Effects of V addition on the mechanical properties at elevated temperatures in a γ”-strengthened NiCoCr-based multi-component alloy

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Journal of Materials Science & Technology 2022年第12期107卷 290-300页

作者： Yunwei Pan Anping Dong Yang Zhou Dafan Du Donghong Wang Guoliang Zhu Baode Sun Shanghai Key Lab of Advanced High-temperature Materials and Precision Forming School of Materials Science and EngineeringShanghai Jiao Tong UniversityShanghai 200240China State Key Lab of Metal Matrix Composites Shanghai Jiao Tong UniversityShanghai 200240China

Ni Co Cr-based multi-component alloys have drawn much attention due to their exceptional ductility and strain hardening capacity.However,insufficient strength-ductility synergy of NiCoCr alloy has always been an issue that prevents it from extensive applications.According to our previous research,the precipitation ofγ”phase can significantly improve the strength-ductility synergy of this alloy system at room temperature.In this study,the effects of V addition onγ”phase stability and high-temperature mechanical properties have been explicitly investigated.The results indicate that V addition can stabilize the metastableγ”phase in this alloy system and prevent it from transforming into a stableδphase at grain boundaries upon 650℃aging,resulting in improved mechanical properties at elevated temperatures.The specific strength ofγ”-strengthened multi-component NiCoCr-based alloy can reach up to 86.2 MPa gcmat 650℃,which is higher than those of Ni-based superalloys,IN 939 and Waspaloy.This work provides theoretical guidance for the novel design of γ”-strengthened alloy for high-temperature applications.

关键词： Multi-component alloys CALPHAD γ”phase Microstructural evolution High-temperature mechanical properties

Selective laser melting of dense and crack-free AlCoCrFeNi_(2.1) eutectic high entropy alloy: Synergizing strength and ductility

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Journal of Materials Science & Technology 2022年第22期117卷 133-145页

作者： Lin He Shiwei Wu Anping Dong Haibin Tang Dafan Du Guoliang Zhu Baode Sun Wentao Yan Shanghai Key Lab of Advanced High-temperature Materials and Precision Forming and State Key Lab of Metal Matrix Composites School of Materials Science and EngineeringShanghai Jiao Tong UniversityShanghai 200240China Department of Mechanical Engineering National University of Singapore117575Singapore School of Intelligent Manufacturing Nanjing University of Science and TechnologyNanjing 210094China

Additively manufactured high-entropy alloys generally suffer from low strength and/or poor ductility.In this work,by leveraging the good castability of eutectic high entropy alloys and high cooling rate of selective laser melting(SLM),we report a nearly fully dense and crack-free as-SLM AlCoCrFeNi_(2.1) eutectic high entropy alloy with an exceptional strength-ductility synergy,showing an ultrahigh yield strength of 982.1±35.2 MPa and an ultimate tensile strength of 1322.8±54.9 MPa together with an elongation to fracture of 12.3±0.5%.Such strength-ductility enhancement is owing to the heterogeneous eutectic microstructure consisting of the columnar,equiaxed,and“L-shape”cells with much refined sizes down to nanoscales.The morphology of cells in the transition zone is related to the misorientation between the growth direction of adjacent layers.This heterogeneous eutectic microstructure is the result of the graingrowth behavior dominated by the mechanisms of the epitaxial growth and growth of heterogeneous nuclei in SLM.Our current results provide a new methodology for the future design of ultrahigh-strength and ductile SLM-fabricated metallic materials including HEAs,and other printable alloys for various structural applications.

关键词： Additive manufacturing High entropy alloy Microstructure Mechanical properties Laser Crack-free

Structural diversity and biological activity of natural p-terphenyls

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Marine Life Science & Technology 2022年第1期4卷 62-73页

作者： guoliang Zhou Tianjiao zhu Qian Che Guojian Zhang Dehai Li Key Laboratory of Marine Drugs School of Medicine and PharmacyChinese Ministry of EducationOcean University of ChinaQingdao266003China Laboratory for Marine Drugs and Bioproducts of Qingdao National Laboratory for Marine Science and Technology Qingdao266237China

p-Terphenyls are aromatic compounds consisting of a central benzene ring substituted with two phenyl groups,and they are mainly isolated from terrestrial and marine organisms.The central ring of p-Terphenyls is usually modified into more oxidized forms,e.g.,para quinone and phenols.In some cases,additional ring systems were observed on the terphenyl-type core structure or between two benzene moieties.p-Terphenyls have been reported to have cytotoxic,antimicrobial,antioxidant andα-glucosidase inhibitory effects.In this review,we will mainly summarize the structural diversity and biological activity of naturally occurring p-Terphenyls referring to the research works published before.

关键词： p-Terphenyl Marine organism Structure Biological activity Cytotoxic

Sufficient dimension reduction in the presence of controlling variables

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Science China Mathematics 2022年第9期65卷 1975-1996页

作者： guoliang Fan Liping zhu School of Economics and Management Shanghai Maritime UniversityShanghai 201306China Center for Applied Statistics and Institute of Statistics and Big Data Renmin University of ChinaBeijing 100872China Institute of Statistics and Big Data Zhejiang Gongshang UniversityHangzhou 310018China

We are concerned with partial dimension reduction for the conditional mean function in the presence of controlling variables.We suggest a profile least squares approach to perform partial dimension reduction for a general class of semi-parametric models.The asymptotic properties of the resulting estimates for the central partial mean subspace and the mean function are provided.In addition,a Wald-type test is proposed to evaluate a linear hypothesis of the central partial mean subspace,and a generalized likelihood ratio test is constructed to check whether the nonparametric mean function has a specific parametric form.These tests can be used to evaluate whether there exist interactions between the covariates and the controlling variables,and if any,in what form.A Bayesian information criterion(BIC)-type criterion is applied to determine the structural dimension of the central partial mean subspace.Its consistency is also established.Numerical studies through simulations and real data examples are conducted to demonstrate the power and utility of the proposed semi-parametric approaches.

关键词： central partial mean subspace controlling variable hypothesis test semi-parametric regression sufficient dimension reduction

Characteristics ofβ-type Ti-41Nb alloy produced by laser powder bed fusion:Microstructure,mechanical properties and in vitro biocompatibility

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Journal of Materials Science & Technology 2022年第29期124卷 260-272页

作者： Zhongjie Li Jiajun Qiu Hao Xu Anping Dong Lin He Guoliang Zhu Dafan Du Hui Xing Xuanyong Liu Baode Sun Shanghai Key Laboratory of Advanced High-Temperature Materials and Precision Forming School of Materials Science and EngineeringShanghai Jiao Tong UniversityShanghai 200240P.R.China State Key Laboratory of High Performance Ceramics and Superfine Microstructure Shanghai Institute of CeramicsChinese Academy of SciencesShanghai 200050P.R.China State Key Laboratory of Metal Matrix Composites School of Materials Science and EngineeringShanghai Jiao Tong UniversityShanghai 200240P.R.China

Aβ-type Ti-41 Nb alloy with high relative density has been successfully fabricated by laser powder bed fusion(L-PBF)using pre-alloyed powders for potential implant application.The homogeneous microstructure can be achieved in L-PBF fabricated(L-PBFed)Ti-41 Nb alloy but slight composition segregation was detected along molten pool boundaries.The L-PBFed alloy was dominated by typical epitaxial columnar grains with strong(001)grain orientation along building direction(BD),and cellular structure was distinguished within the columnar grains.The main reasons for this microstructure can be attributed to effective thermal gradient and epitaxial growth.L-PBFed alloy exhibited higher mechanical strength compared with cold rolling plus annealing(CRA)alloy due to the finer grains,dislocations accumulation and different TRIP behaviors,accompanied by good ductility.It also exhibited much lower thermal conductivity and better hydrophilic feature than those of CP-Ti.Besides,the L-PBFed alloy exhibited slightly better cell spread and cell proliferation rates compared with CP-Ti.Moreover,L-PBFed alloy presented better alkaline phosphatase(ALP)activities and extracellular matrix(ECM)mineralization,which suggests that the L-PBFed alloy can stimulate the osteogenic differentiation of rat bone mesenchymal stem cells.The Ti-41 Nb alloy,fabricated by L-PBF,reveals a good combination of mechanical properties,physicochemical properties and biocompatibility,exhibiting the great potential as the dental implant.

关键词： Laser powder bed fusion Ti-41Nb Microstructure Mechanical properties In vitro biocompatibility

Effect of vibration on interfacial microstructure and mechanical properties of Mg/Al bimetal prepared by a novel compound casting

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Journal of Magnesium and Alloys 2022年第8期10卷 2296-2309页

作者： Feng Guan Wenming Jiang Guangyu Li Junwen zhu Junlong Wang guoliang Jie Zitian Fan State Key Laboratory of Materials Processing and Die&Mould Technology School of Materials Science and EngineeringHuazhong University of Science and TechnologyWuhan 430074China State Key Laboratory for Advanced Metals and Materials University of Science and Technology BeijingBeijing 100083China

In this work,a vibration was applied in the preparation of the Mg/Al bimetal by a novel compound casting in order to improve the mechanical properties of the Mg/Al bimetal,and the effect of the vibration on the interfacial microstructure and mechanical properties of the Mg/Al bimetal was investigated.The results indicated that the vibration had a significant effect on the interfacial microstructure and mechanical properties of the Mg/Al bimetal,but it did not change the phase compositions of the interface,which was composed of layerⅠ(Al3Mg2+Mg2Si),layerⅡ(Al_(12)Mg_(17)+Mg_(2)Si)and layerⅢ(Al_(12)Mg_(17)/δ-Mg).Without vibration,the Mg_(2)Si phase with a needle-like morphology mainly aggregated in the layerⅡof the interface.After the application of the vibration,the SEM and EBSD analysis results showed that the Mg_(2)Si and Al3Mg2phases in the interface were obviously refined,and the distribution of the Mg_(2)Si became more uniform,due to the strong forced convection of the molten metal resulting from the vibration.The TEM analysis indicated that the interface between the A_(l3)Mg_(2) and Mg_(2)Si phases was non-coherent,suggesting the Mg_(2)Si particles cannot act as a heterogeneous nucleation base during the solidification process of the interface.Compared to the Mg/Al bimetal without vibration,the shear strength of the Mg/Al bimetal with vibration increased by about 50%from 31.7 MPa on average to 47.5 MPa,and the hardness of the layer I of the interface increased,and the hardness of the layerⅢdecreased.The fracture surface transformed from a flat fracture morphology without vibration to an irregular zigzag fracture morphology.

关键词： Mg/Al bimetal Vibration Compound casting Interfacial microstructure Bonding properties

A Prior Information Enhanced Extraction Framework for Document-level Financial Event Extraction

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Data Intelligence 2021年第3期3卷 460-476页

作者： Haitao Wang Tong zhu Mingtao Wang guoliang Zhang Wenliang Chen School of Computer Science and Technology Soochow UniversitySuzhou 215006China

Document-level financial event extraction(DFEE) is the task of detecting events and extracting the corresponding event arguments in financial documents, which plays an important role in information extraction in the financial domain. This task is challenging as the financial documents are generally long text and event arguments of one event may be scattered in different sentences. To address this issue, we proposed a novel Prior Information Enhanced Extraction framework(PIEE) for DFEE, leveraging prior information from both event types and pre-trained language models. Specifically, PIEE consists of three components: event detection, event argument extraction, and event table filling. In event detection, we identify the event type. Then, the event type is explicitly used for event argument extraction. Meanwhile, the implicit information within language models also provides considerable cues for event arguments localization. Finally, all the event arguments are filled in an event table by a set of predefined heuristic rules. To demonstrate the effectiveness of our proposed framework, we participated in the share task of CCKS2020 Task 4-2: Documentlevel Event Arguments Extraction. On both Leaderboard A and Leaderboard B, PIEE took the first place and significantly outperformed the other systems.

关键词： Event extraction Information extraction Financial event Event detection Event argument extraction

Radiation Spectral Analysis of 3D Dust Molecular Clusters(PAHs)and Peptoids under Ionization and Electric Field in ISM

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Research in Astronomy and Astrophysics 2024年第1期24卷 70-77页

作者： Ruiqing Wu Chunhua zhu guoliang Lü Xiaojiao Zhang Xizhen Lu Jinlong Yu Wujin Chen Mengqiu Long School of Physics and Electronics Central South UniversityChangsha 410083China School of Physical Science and Technology Xinjiang UniversityUrumqi 830046China School of Microelectronics and Physics Hunan University of Technology and BusinessChangsha 410205China College of Mechanical and Electronic Engineering Tarim UniversityAlar 843300China School of Medicine Xinjiang Medical UniversityUrumqi 830011China

Polycyclic aromatic hydrocarbons(PAHs),PANHs,and peptoids dust spectral calculations from the interstellar medium(ISM)are important for dust observations and theory.Our goal is to calculate the radiation spectrum of spherical PAHs dust clusters in a vacuum containing ionized and applied in the presence of an electric field.We propose a new simple computational model to calculate the size of three-dimensional spherical dust clusters formed by different initial dust structures.By the Vienna Ab-initio Simulation Package code,the density functional theory with the generalized approximation was used to calculate the electron density gradient and obtain the radiation spectrum of dust.When the radius of spherical dust clusters is~[0.009-0.042]μm,the dust radiation spectrum agrees well with the Z=0.02 mMMP stellar spectra,and the PAHs radiation spectrum of NGC 4676 at wavelengths of(0-5]μm and(5-10]μm,respectively.In the ionized state,the N-PAH,C_(10)H_(9)N,2(C_(4)H_(4))^(1+),and peptoids 4(CHON),(C_(8)H_(10)N_(2)O_(5))^(1+)dust clusters at 3.3μm,while the 2(C_(22)H_(21)N_(3)O_(2))^(1+),4(CHON)dust clusters at 5.2μm have obvious peaks.There is a characteristic of part of PAHs and peptoids clusters radiation at the nearinfrared wavelength of 2μm.However,especially after applying an electric field to the dust,the emission spectrum of the dust increases significantly in the radiation wavelength range[3-10]μm.Consequently,the dust clusters of PAHs,PANHs,and peptoids of the radius size~[0.009-0.042]μm are likely to exist in the ISM.

关键词： ISM:structure ISM:molecules radiation mechanisms:general (ISM:)dust extinction