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Earthquake Research Advances 2024年第1期4卷 67-75页

作者： Yuteng Cao zhe qu Xiaodong Ji Key Laboratory of Earthquake Engineering and Engineering Vibration Institute of Engineering MechanicsChina Earthquake AdministrationHarbin150080China Key Laboratory of Earthquake Disaster Mitigation Ministry of Emergency ManagementHarbin150080China Key Laboratory of Civil Engineering Safety and Durability of China Education Ministry Department of Civil EngineeringTsinghua UniversityBeijing100084China

To enable the experimental assessment of the seismic performance of full-scale nonstructural elements with multiple engineering parameters(EDPs),a three-layer testbed named Nonstructural Element Simulator on Shake Table(NEST)has been developed.The testbed consists of three consecutive floors of steel structure.The bottom two floors provide a space to accommodate a full-scale room.To fully explore the flexibility of NEST,we propose a novel control strategy to generate the required shake table input time histories for the testbed to track the target floor motions of the buildings of interest with high accuracy.The control strategy contains two parts:an inverse dynamic compensation via simulation of feedback control systems(IDCS)algorithm and an offline iteration procedure based on a refined nonlinear numerical model of the testbed.The key aspects of the control strategy were introduced in this paper.Experimental tests were conducted to simulate the seismic responses of a full-scale office room on the 21^(st)floor of a 42-story high-rise building.The test results show that the proposed control strategy can reproduce the target floor motions of the building of interest with less than 20%errors within the specified frequency range.

关键词： Shake table test Nonstructural element High-rise building Open-loop IDCS algorithm Off-line iteration

Proper interpretation of sectional analysis results

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Earthquake Research Advances 2024年第2期4卷 65-71页

作者： Juyuan zheng Yuli Huang zhe qu Key Laboratory of Earthquake Engineering and Engineering Vibration Institute of Engineering MechanicsChina Earthquake AdministrationHarbin150080China Key Laboratory of Earthquake Disaster Mitigation Ministry of Emergency ManagementHarbin150080China Arup 560 Mission StreetSuite 700San FranciscoCA94105United States

Displacement control algorithms commonly used to evaluate axial force-bending moment(PM)diagrams may lead to incorrect interpretations of the strength envelopes for asymmetric sections.This paper aims to offer valuable insights by comparing existing displacement control algorithms with a newly proposed force control algorithm.The main focus is on the PM diagrams of three example sections that exhibit varying degrees of asymmetry.The comparative study indicates that conventional displacement control algorithms inevitably introduce non-zero out-of-plane bending moments.The reported PM diagram in such cases erroneously neglects the out-of-plane moment and fails to represent the strength envelope accurately.This oversight results in significant and unconservative errors when verifying the strength of asymmetric sections.

关键词： Fiber section model Axial force-moment interaction diagram Limit state Failure surface

A discretely damped SDOF model for the rocking response of freestanding blocks

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Earthquake Engineering and Engineering Vibration 2022年第3期21卷 729-740页

作者： Liu Hanquan Huang Yuli qu zhe Key Laboratory of Earthquake Engineering and Engineering Vibration Institute of Engineering MechanicsChina Earthquake AdministrationKey Laboratory of Earthquake Disaster MitigationMinistry of Emergency ManagementHarbin 150080China Sanhe 065201China Arup San FranciscoCA 94105USA

This paper presents a single-degree-of-freedom(SDOF)constitutive model for assessing the performance of freestanding block contents of buildings.The model incorporates a bespoke damper to account for energy dissipation associated with rocking.It is advantageous in its direct correlation,via energy conservation,to the restitution coefficient for impact during rocking.A comparative study with the existing SDOF rocking models shows that the proposed model significantly improves the accuracy of free-rocking simulations,in which inherent damping predominantly affects response.It provides a promising and efficient tool for computationally intensive performance evaluation of nonstructural components.

关键词： contents rigid block equivalent viscous damping free rocking forced rocking single-degree-of-freedom system

Role of dampers on the seismic performance of pin-supported wall-frame structures

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Earthquake Engineering and Engineering Vibration 2023年第2期22卷 453-467页

作者： Wang Xiaoyue qu zhe Gong Ting Key Laboratory of Earthquake Engineering and Engineering Vibration Institute of Engineering MechanicsChina Earthquake AdministrationSanhe 065201China Key Laboratory of Earthquake Disaster Mitigation Ministry of Emergency ManagementHarbin 150080China China Re Catastrophe Risk Management Company Ltd. Beijing 100000China

Pin-supported(PS)walls have been proven effective in avoiding weak story failure of frame structures by increasing the height-wise continuous stiffness and producing uniform distribution of story drifts.However,little attention has been given to the floor velocity or acceleration responses of PS wall-frame structures,which predominate the seismic damage of various nonstructural components that are critical to the immediate occupancy and quick recovery of buildings.This paper presents a numerical evaluation of the floor velocity and acceleration responses of PS wall-frame structures,highlighting the effects of different types of dampers accompanying the PS walls.The results show that the PS walls alone significantly increase the peak floor velocity(PFV)and peak floor acceleration(PFA)responses.PS wall-frame structures with either steel or viscoelastic(VE)dampers are much less effective in reducing the PFV or PFA responses than they are in reducing the peak inter-story drift ratio(PIDR).The impact of this behavior is demonstrated by a seismic fragility analysis that incorporates demand parameters combining the maximum PIDR,average PFV and PFA.The results show that the use of VE dampers rather than hysteretic dampers results in better protection of nonstructural components in PS wall-frame structures.

关键词： strong spine system energy-dissipating device floor acceleration floor velocity nonstructural damage

Miura origami based reconfigurable polarization converter for multifunctional control of electromagnetic waves

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Photonics Research 2024年第3期12卷 581-586页

作者： ZHIBIAO ZHU YONGFENG LI zhe QIN LIXIN JIANG WENJIE WANG HONGYA CHEN JIAFU WANG YONGQIANG PANG SHAOBO qu Shaanxi Key Laboratory of Artificially-Structured Functional Materials and Devices Air Force Engineering UniversityXi’an 710051China School of Electronic Science and Engineering Xi’an Jiaotong UniversityXi’an 710049China

Polarization is one of the basic characteristics of electromagnetic(EM)waves,and its flexible control is very important in many practical applications.At present,most of the multifunction polarization metasurfaces are electrically tunable based on PIN and varactor diodes,which are easy to operate and have strong real-time performance.However,there are still some problems in them,such as few degrees of freedom of planar structure control,complex circuit,bulky sample,and high cost.In view of these shortcomings,this paper proposes a Miura origami based reconfigurable polarization conversion metasurface for multifunctional control of EM waves.The interaction between the electric dipoles is changed by adjusting the folding angleθ,thereby tuning the operating frequency of the polarization conversion and the polarization state of the reflected wave.This mechanical control method brings more degrees of freedom to manipulate EM waves.And the processed sample is with lightweight and low cost.To verify the performance of the proposed origami polarization converter,a Miura origami structure loaded with metal split rings is designed and fabricated.The operating frequency of the structure can be tuned in different folding states.In addition,by controlling the folding angleθ,linear-to-linear and linear-to-circular polarization converters can be realized at different folding states.The proposed Miura origami polarization conversion metasurface provides a new idea for reconfigurable linear polarization conversion and multifunctional devices.

关键词： polarization reconfigurable tuning

Anisotropic magnetism and band evolution induced by ferromagnetic phase transition in titanium-based kagome ferromagnet SmTi_3Bi_4

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Science China(Physics,Mechanics & Astronomy) 2024年第6期67卷 137-145页

作者： zhe zheng Long Chen Xuecong Ji Ying Zhou Gexing qu Mingzhe Hu Yaobo Huang Hongming Weng Tian Qian Gang Wang Beijing National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China School of Physics and Engineering Henan University of Science and TechnologyLuoyang 471023China Shanghai Synchrotron Radiation Facility Shanghai Advanced Research InstituteChinese Academy of SciencesShanghai 201210China Songshan Lake Materials Laboratory Dongguan 523808China CAS Center for Excellence in Topological quantum Computation Chinese Academy of SciencesBeijing 100190China

Kagome magnets with diverse topological quantum responses are crucial for next-generation topological engineering.The anisotropic magnetism and band evolution induced by ferromagnetic phase transition(FMPT)is reported in a newly discovered titanium-based kagome ferromagnet Sm Ti3Bi4,which features a distorted Ti kagome lattice and Sm atomic zig-zag chains.Temperature-dependent resistivity,heat capacity,and magnetic susceptibility reveal a ferromagnetic ordering temperature Tc of23.2 K.A large magnetic anisotropy,observed by applying the magnetic field along three crystallographic axes,identifies the b axis as the easy axis.Angle-resolved photoemission spectroscopy with first-principles calculations unveils the characteristic kagome motif,including the Dirac point at the Fermi level and multiple van Hove singularities.Notably,a band splitting and gap closing attributed to FMPT is observed,originating from the exchange coupling between Sm 4 f local moments and itinerant electrons of the kagome Ti atoms,as well as the time-reversal symmetry breaking induced by the long-range ferromagnetic order.Considering the large in-plane magnetization and the evolution of electronic structure under the influence of ferromagnetic ordering,such materials promise to be a new platform for exploring the intricate electronic properties and magnetic phases based on the kagome lattice.

关键词： kagome lattice anisotropic magnetism band splitting ferromagnetic phase transition ARPES

Moisture‑Electric–Moisture‑Sensitive Heterostructure Triggered Proton Hopping for quality‑Enhancing Moist‑Electric Generator

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Nano-Micro Letters 2024年第3期16卷 351-366页

作者： Ya’nan Yang Jiaqi Wang zhe Wang Changxiang Shao Yuyang Han Ying Wang Xiaoting Liu Xiaotong Sun Liru Wang Yuanyuan Li Qiang Guo Wenpeng Wu Nan Chen Liangti qu Key Laboratory of Cluster Science Ministry of Education of ChinaKey Laboratory of Photoelectronic/Electrophotonic Conversion MaterialsSchool of Chemistry and Chemical EngineeringBeijing Institute of TechnologyBeijing 100081People’s Republic of China Yangtze Delta Region Academy of Beijing Institute of Technology Jiaxing 314019People’s Republic of China Department of Chemistry Key Laboratory of Organic Optoelectronics&Molecular EngineeringMinistry of EducationTsinghua UniversityBeijing 100084People’s Republic of China

Moisture-enabled electricity(ME)is a method of converting the potential energy of water in the external environment into electrical energy through the interaction of functional materials with water molecules and can be directly applied to energy harvesting and signal expression.However,ME can be unreliable in numerous applications due to its sluggish response to moisture,thus sacrificing the value of fast energy harvesting and highly accurate information representation.Here,by constructing a moisture-electric-moisture-sensitive(ME-MS)heterostructure,we develop an efficient ME generator with ultra-fast electric response to moisture achieved by triggering Grotthuss protons hopping in the sensitized ZnO,which modulates the heterostructure built-in interfacial potential,enables quick response(0.435 s),an unprecedented ultra-fast response rate of 972.4 mV s^(−1),and a durable electrical signal output for 8 h without any attenuation.Our research provides an efficient way to generate electricity and important insight for a deeper understanding of the mechanisms of moisture-generated carrier migration in ME generator,which has a more comprehensive working scene and can serve as a typical model for human health monitoring and smart medical electronics design.

关键词： Moist-electric generators Grotthuss proton hopping Fast response Durable electrical output Personal health monitoring

Esophageal cancer screening,early detection and treatment:Current insights and future directions

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World Journal of Gastrointestinal Oncology 2024年第4期16卷 1180-1191页

作者： Hong-Tao qu Qing Li Liang Hao Yan-Jing Ni Wen-Yu Luan zhe Yang Xiao-Dong Chen Tong-Tong Zhang Yan-Dong Miao Fang Zhang Department of Emergency Yantai Mountain HospitalYantai 264000Shandong ProvinceChina Cancer Center Yantai Affiliated Hospital of Binzhou Medical UniversityThe 2nd Medical College of Binzhou Medical UniversityYantai 264100Shandong ProvinceChina

Esophageal cancer ranks among the most prevalent malignant tumors globally,primarily due to its highly aggressive nature and poor survival rates.According to the 2020 global cancer statistics,there were approximately 604000 new cases of esophageal cancer,resulting in 544000 deaths.The 5-year survival rate hovers around a mere 15%-25%.Notably,distinct variations exist in the risk factors associated with the two primary histological types,influencing their worldwide incidence and distribution.Squamous cell carcinoma displays a high incidence in specific regions,such as certain areas in China,where it meets the cost-effect-iveness criteria for widespread endoscopy-based early diagnosis within the local population.Conversely,adenocarcinoma(EAC)represents the most common histological subtype of esophageal cancer in Europe and the United States.The role of early diagnosis in cases of EAC originating from Barrett's esophagus(BE)remains a subject of controversy.The effectiveness of early detection for EAC,particularly those arising from BE,continues to be a debated topic.The variations in how early-stage esophageal carcinoma is treated in different regions are largely due to the differing rates of early-stage cancer diagnoses.In areas with higher incidences,such as China and Japan,early diagnosis is more common,which has led to the advancement of endoscopic methods as definitive treatments.These techniques have demonstrated remarkable efficacy with minimal complications while preserving esophageal functionality.Early screening,prompt diagnosis,and timely treatment are key strategies that can significantly lower both the occurrence and death rates associated with esophageal cancer.

关键词： Esophageal cancer Screening Early detection Treatment Endoscopic mucosal resection Endoscopic submucosal dissection

On civil engineering disasters and their mitigation

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Earthquake Engineering and Engineering Vibration 2018年第1期17卷 1-10页

作者： Xie Lili qu zhe Key Laboratory of Earthquake Engineering and Engineering Vibration Institute of Engineering MechanicsChina Earthquake Administration

Civil engineering works such as buildings and infrastructure are the carriers of human civilization. They are, however, also the origins of various types of disasters, which are referred to in this paper as civil engineering disasters. This paper presents the concept of civil engineering disasters, their characteristics, classification, causes, and mitigation technologies. Civil engineering disasters are caused primarily by civil engineering defects, which are usually attributed to improper selection of construction site, hazard assessment, design and construction, occupancy, and maintenance. From this viewpoint, many so-called natural disasters such as earthquakes, strong winds, floods, landslides, and debris flows are substantially due to civil engineering defects rather than the actual natural hazards. Civil engineering disasters occur frequently and globally and are the most closely related to human beings among all disasters. This paper emphasizes that such disasters can be mitigated mainly through civil engineering measures, and outlines the related objectives and scientific and technological challenges.

关键词： disaster hazard civil engineering disaster earthquake

Lessons from the seismic behavior of a steel grid roof structure heavily damaged in Lushan earthquake

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Earthquake Engineering and Engineering Vibration 2019年第1期18卷 95-111页

作者： Li Jichao qu zhe Wang Tao Key Laboratory of Earthquake Engineering and Engineering Vibration Institute of Engineering MechanicsChina Earthquake Administration

The seismic behavior of a school gymnasium, whose steel grid roof was heavily damaged during the Mw6.6 Lushan earthquake in 2013, is simulated through nonlinear dynamic analysis. The simulated damage is compared with field observations to validate the numerical model, based on which a parametric study was performed to provide insight into the failure process and damage patterns of steel grids. The results suggest that the grid damage is strongly related to roofsubstructure interactions. These include not only the substructure's amplification of the vibration, but the uncoordinated displacement of the substructure's columns which support the grid also play an equally important role. In particular, the latter effect may significantly alter the internal force distribution in the steel grid and lead to unexpected buckling of members that are proportioned as tension-only members. While such interactions are generally not accounted for in the design practice for grid structures in China, similar seismic damage may be expected for other existing grid roofs in future earthquakes. As is also demonstrated in this study, seismic isolation of the roof is a promising solution to protect grid roof structures by mitigating the detrimental effects of roof-substructure interactions.

关键词： Lushan earthquake steel space structure roof-substructure interaction nonlinear dynamic analysis seismic isolation vertical ground motion