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Mechanics of twisted and coiled tube-based artificial muscles driven by hydraulic pressure

Science China(Technological Sciences) 2025年第4期68卷 72-81页

作者： Hao LIU Zhiya ZHANG Lei LIU Dabiao LIU Department of Engineering Mechanics School of Aerospace EngineeringHuazhong University of Science and TechnologyWuhan430074China Hubei Key Laboratory of Engineering Structural Analysis and Safety Assessment Wuhan430074China

The twisted and coiled polymer(TCP)artificial muscles driven by hydraulic pressure offer high mechanical efficiency and power *** relation between geometry,mechanics,and actuation performance for this kind of muscle is *** this study,we study the mechanics and actuation characteristics of TCP tube-based muscles driven by hydraulic pressure through experiment,theory,and finite element *** for the helical geometry and transverse isotropy of the TCP muscles,we develop a phenomenological model to predict the actuation performance of TCP tube-based *** torsional and tensile actuation characteristics of the twisted and TCP tube-based muscle driven by hydraulic pressure are *** is found that the cold drawing enhances the anisotropy of the polyvinyl chloride tube,resulting in an improved actuation performance of the twisted and TCP *** torsional actuation in the twisted tube reaches the maximum at a critical bias angle for a given pressure,while the tensile actuation in TCP muscles increases with the coil *** theoretical predictions and simulations are in good agreement with experimental *** study is significant for guiding the design of TCP tube-based muscles and achieving their precise actuation control.

关键词： artificial muscles hydraulic pressure actuation characteristics anisotropy

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Real-time traffic enhancement scheduling for train communication networks based on TSN

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Journal of Traffic and Transportation engineering(English Edition) 2025年第1期12卷 34-51页

作者： Deqiang He Zeqian Chen Daliang Sun Zhenzhen Jin Yanjun Chen Rui Ma Chen Liang Key Laboratory of Disaster Prevention and Structural Safety of Ministry of Education Guangxi Key Laboratory of Manufacturing System & Advanced Manufacturing TechnologySchool of Mechanical EngineeringGuangxi University

With the increasing data volume of train on-board system, real-time performance has become the most critical factor to ensure the safety of train operation. Considering that standard Ethernet cannot meet the real-time requirement of existing train communication network(TCN), the time-sensitive network(TSN) technology for TCN is introduced. To solve the time-delay problem, an adaptive switch queue selection mechanism for traffic scheduling is proposed. Firstly, the topology model of TCN based on TSN and the traffic model are described. Then, the K shortest path routing algorithm based on load balancing provides the optimal routing for the scheduling process. Finally, the adaptive switch queue selection mechanism is introduced to solve the aggregation flow conflict problem effectively, queue resources are properly allocated, and the gate control list(GCL) of each frame in the queue is obtained. Experimental results show that compared with the traditional constraint model, the schedulability of the model with an adaptive switch queue selection mechanism increases by 33.0%, and the maximum end-to-end delay and network jitter decrease by 19.1% and 18.6% on average respectively. It can provide theoretical support and application reference for the real-time performance optimization of TCN based on TSN.

关键词： Train communication network Time-sensitive network Adaptive switch queue selection mechanism Gate control list Real-time

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A review of test methods for uniaxial compressive strength of rocks:Theory,apparatus and data processing

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Journal of Rock Mechanics and Geotechnical engineering 2025年第3期17卷 1889-1905页

作者： Wei-Qiang Xie Xiao-Li Liu Xiao-Ping Zhang Quan-Sheng Liu En-ZhiWang State Key Laboratory of Hydroscience and Engineering Tsinghua UniversityBeijing100084China Yunlong Lake Laboratory of Deep Underground Science and Engineering Xuzhou221000China The Key Laboratory of Safety for Geotechnical and Structural Engineering of Hubei Province School of Civil EngineeringWuhan UniversityWuhan430072China

The uniaxial compressive strength(UCS)of rocks is a vital geomechanical parameter widely used for rock mass classification,stability analysis,and engineering design in rock *** UCS testing methods and apparatuses have been proposed over the past few *** objective of the present study is to summarize the status and development in theories,test apparatuses,data processing of the existing testing methods for UCS *** starts with elaborating the theories of these test *** the test apparatus and development trends for UCS measurement are summarized,followed by a discussion on rock specimens for test apparatus,and data processing ***,the method selection for UCS measurement is *** reveals that the rock failure mechanism in the UCS testing methods can be divided into compression-shear,compression-tension,composite failure mode,and no obvious failure *** trends of these apparatuses are towards automation,digitization,precision,and multi-modal *** size correction methods are commonly *** is to develop empirical correlation between the measured indices and the specimen *** other is to use a standard specimen to calculate the size correction *** to five input parameters are commonly utilized in soft computation models to predict the UCS of *** selection of the test methods for the UCS measurement can be carried out according to the testing scenario and the specimen *** engineers can gain a comprehensive understanding of the UCS testing methods and its potential developments in various rock engineering endeavors.

关键词： Uniaxial compressive strength(UCS) UCS testing methods Test apparatus Data processing

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Risk-Targeted Design Spectra for Uniform Risk Seismic Design

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Seismological Research Letters 2025年第3期96卷 1820-1833页

作者： Wang, Cong Lu, Da-Gang Key Laboratory of Building Structural Retrofitting and Underground Space Engineering Ministry of Education Shandong Jianzhu University Jinan China Key Laboratory of Structural Dynamic Behaviors and Control Ministry of Education Harbin Institute of Technology Harbin China

The uniform hazard response spectrum only considers the seismic hazard of a site, without taking into account the seismic fragility of the structure. As a result, structures designed based on this spectrum may exhibit varying levels of collapse risk under earthquakes in different regions. To this end, first, various cases are employed to determine a first-order approximation of the seismic hazard function H(x), followed by a validation of its rationality. Subsequently, with the objective of achieving uniform collapse risk, considering both seismic hazard and structural fragility, single anchor point, double anchor points, and multiple anchor points methods are proposed to construct the risk-targeted seismic design spectra for frequent earthquake (FE), design basis earthquake (DBE), maximum considered earthquake (MCE), and very rare earthquake (VRE). Furthermore, a comprehensive study is conducted to analyze the risk-targeted seismic design spectra corresponding to different seismic design levels, site classes, and characteristic periods constructed using the multiple anchor points method. In addition, a comparative analysis is conducted on the risk-targeted seismic design spectra constructed using different methods. The study indicates that determining H(x) based on DBE and VRE is reasonable, and the relative difference between the risk-targeted ground motion (RTGM) derived from this case and the RTGM obtained by determining H(x) based on probabilistic seismic hazard analysis is within 4%. The risk-targeted seismic design spectra constructed using three different methods show overall similarity. The single anchor point method offers simplicity in calculations and ensures that the uniform risk seismic design spectrum aligns with the uniform hazard seismic design spectrum in terms of spectral shape. Although the multiple anchor points method involves increased computational effort, it allows for the consideration of seismic hazard at multiple periods. © Seismological

关键词： Risk assessment

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New analytical solutions for free vibration of embedded magneto-electro-elastic cylindrical shells with step-wise thickness variations

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Applied Mathematics and Mechanics(English Edition) 2025年第3期46卷 447-466页

作者： Jufang JIA Huilin YIN Qinyu YU Jiabin SUN Xinsheng XU Zhenhuan ZHOU School of Mechanical Engineering and Automation Dalian Polytechnic UniversityDalian 116034Liaoning ProvinceChina State Key Laboratory of Structural Analysis Optimization and CAE Software for Industrial EquipmentSchool of Mechanics and Aerospace EngineeringDalian University of TechnologyDalian 116024Liaoning ProvinceChina State Key Laboratory of Structural Analysis Optimization and CAE Software for Industrial EquipmentSchool of Chemical EngineeringOcean and Life SciencesDalian University of TechnologyPanjin 124221Liaoning ProvinceChina

In recent years,magneto-electro-elastic(MEE)cylindrical shells with step-wise thicknesses have shown significant potential in the field of vibration energy *** aid the design of such energy harvesting devices,an accurate free vibration analysis of embedded MEE cylindrical shells with step-wise thicknesses is performed within the framework of symplectic *** using the Legendre transformation,a new known vector is defined to transform the higher-order partial differential governing equations into a set of lower-order ordinary differential ***,the original vibration analysis is regarded as an eigen problem in the symplectic space,and analytical solutions can be represented by the symplectic *** numerical examples,the new analytical solutions are compared with the existing results,and good agreement is ***,the effects of critical design parameters on free vibration characteristics are thoroughly *** numerical results can serve as benchmarks for the development of other approximate or numerical methods.

关键词： analytical solution free vibration magneto-electro-elastic(MEE)material cylindrical shell with variable thickness symplectic method

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Regulating the composition, structure, and nanoscale dimensions of Yb_(2)Si_(2)O_(7) environmental barrier coating to achieve a biomimetic teakwood-like functional structure by waste gas recycling

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Journal of Advanced Ceramics 2025年第2期14卷 87-97页

作者： Jungui Zhang Guifang Han Xinxin Cao Xiaofeng Zhang Jingde Zhang Min Liu Kesong Zhou Key Laboratory for Liquid-Solid Structural Evolution and Processing of Materials(Ministry of Education) School of Materials Science and EngineeringShandong UniversityJinan 250061China National Engineering Laboratory for Modern Materials Surface Engineering Technology&The Key Lab of Guangdong for Modern Surface Engineering Technology&Guangdong-Hong Kong Joint Laboratory of Modern Surface Engineering Technology Institute of New MaterialsGuangdong Academy of SciencesGuangzhou 510650China

The unique multilayer, multiscale structure of teakwood results in excellent mechanical and long-term environmental stability, providing inspiration for the biomimetic design of environmental barrier coating (EBC) structures. However, achieving the desired biomimetic structure control in high-temperature plasma spraying is a challenging task that requires new technological breakthroughs. In this study, a multiscale nano Yb_(2)Si_(2)O_(7)–Yb_(2)SiO_(5) (YbDS–YbMS) composite EBC with a teakwood-like lamellar structure was realized via a novel alternating vapor/liquid phase deposition method involving plasma spraying-physical vapor deposition (PS-PVD). Volatilized waste SiO_(2) from Yb_(2)Si_(2)O_(7) (YbDS) was reused and deposited on the coating surface during the spraying process, where a regularly arranged multilayer structure was formed in the coating by the alternate deposition of gaseous SiO_(2) and droplet YbDS. In addition, SiO_(2) on the coated surface formed nanoclusters and dome-shaped nanocrystals via homogeneous and heterogeneous nucleation, respectively, and some of them gradually formed a continuous nanofilm as the arc current increased. The deposited SiO_(2) reacted in situ with the decomposed phase YbMS in the coating to form YbDS, preserving its multiscale nanostructure after heat treatment and enabling the preparation of the YbDS–YbMS composite coating. This work provides a new design strategy and method for the preparation of coatings using YbDS and other spray powders with similar decomposition and volatilization characteristics during the plasma spraying process.

关键词： teakwood-like lamellar structure alternating vapor/liquid phase deposition nanofilm Yb_(2)Si_(2)O_(7)-Yb_(2)SiO_(5)(YbDS-YbMS)composite coating environmental barrier coating(EBC)

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Molecular Dynamics Study on the Interactions of 1/2Edge Dislocations with Voids and Ni_(3)Al Precipitates in FCC Ni

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Acta Mechanica Solida Sinica 2025年第1期38卷 1-13页

作者： Wendong Cui Junfeng Nie Pandong Lin Lei He Institute of Nuclear and New Energy Technology Key Laboratory of Advanced Reactor Engineering and Safety of Ministry of EducationTsinghua UniversityBeijing100084China Ministry of Education Key Laboratory for Liquid-Solid Structural Evolution and Processing of MaterialsSchool of Materials Science and EngineeringShandong UniversityJinan250061China

Nickel-based alloys are the primary structural materials in steam generators of high-temperature gas *** understand the irradiation effect of nickel-based alloys,it is necessary to examine dislocation movement and its interaction with irradiation defects at the *** due to voids and Ni_(3)Al precipitates may significantly impact irradiation damage in nickel-based *** paper employs the molecular dynamics method to analyze the interaction between edge dislocations and irradiation defects(void and Ni_(3)Al precipitates)in face-centered cubic *** effects of temperature and defect size on the interaction are also *** results show that the interaction process of the edge dislocation and irradiation defects can be divided into four stages:dislocation free slip,dislocation attracted,dislocation pinned,and dislocation *** modes include the formation of stair-rod dislocations and the climbing of extended dislocation bundles for voids,as well as the generation of stair-rod dislocation and dislocation shear for ***,the interactions of edge dislocations with voids and Ni_(3)Al precipitates are strongly influenced by temperature and defect size.

关键词： Void Ni_(3)Al precipitate Nickel Edge dislocation Molecular dynamics

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Mechanical Characterization of an Innovative Textile-Reinforced Mortar System Combined with Thermal Insulation for Application to Masonry Walls 18th

Mechanical Characterization of an Innovative Textile-Reinfor...

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18th International Brick and Block Masonry Conference, IB2MaC 2024

作者： Askouni, Paraskevi D. Kapsalis, Panagiotis Papanicolaou, Catherine G. Triantafillou, Thanasis Structural Materials Laboratory Department of Civil Engineering University of Patras Rio26504 Greece

ISBN: (纸本)9783031733093

The current study focuses on the experimental investigation of an integrated seismic/energy upgrading system comprising a textile-reinforced mortar (TRM) overlay combined with extruded polystyrene (XPS) boards. TRM is a proven strengthening/rehabilitation technique for both masonry and concrete structures comprising externally bonded fibrous girds by means of inorganic binders. XPS is a closed-cell polymeric foam that is widely used as insulation of reinforced concrete elements and masonry infills. The integrated TRM-XPS system in question is investigated herein in conjunction with masonry substrates. In this work, TRM consists of two layers of a dry carbon fiber textile embedded in a fiber-reinforced, polymer-modified cementitious mortar;the latter is the commercial product typically used as the adhesive mortar to bond and render XPS insulation boards ("XPS adhesive"). XPS boards are 20 mm thick. Material characterization tests include: (1) uniaxial tensile tests on TRM prismatic coupons;(2) single-lap/single-prism shear bond tests on TRM/masonry and TRM-XPS/masonry joints (XPS positioned either in between the TRM and the substrate or on top of the TRM);and, (3) concentric compression tests on perforated clay brick wallettes furnished with unilateral TRM jackets. It is concluded that: (i) the "XPS adhesive" is suitable for use as matrix in TRM qualifying as strain-hardening composites;(ii) bond-wise (when this type of composite is used as externally bonded reinforcement), the weak link is the "XPS adhesive" resulting in interlaminar shear failure regardless of the position of the XPS board in respect to the TRM;and (iii) the compressive strength of wallettes increases by up to 22% when unilaterally reinforced with TRM jackets. © The Author(s), under exclusive license to Springer Nature Switzerland AG 2025.

关键词： Tensile testing

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Short-range electronic engineering by coupling Fe phthalocyanines with MOF-derived N,S-doped carbon nanorods for oxygen reduction

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Science China Chemistry 2025年第5期68卷 1859-1868页

作者： Jie Liu Qiu Ye Yi Wu Junliang Chen Yongjie Ge Linjie Zhang Reza Abazari Jinjie Qian Key Laboratory of Carbon Materials of Zhejiang Province College of Chemistry and Materials EngineeringWenzhou University State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of Sciences Department of Chemistry Faculty of ScienceUniversity of Maragheh

Molecular catalysts like metal phthalocyanines（MPc） hold significant promise for diverse applications in renewable energy conversion and *** their inherent catalytic activity in the oxygen reduction reaction（ORR）,enhancing their practical applicability necessitates addressing challenges in electrical conductivity and catalytic stability through effective control of electron distribution within the *** this work,we have successfully synthesized an electrocatalyst featuring FePc molecules anchored onto N,S co-doped carbon nanorods from a pillar-layer metal-organic framework（MOF）,designated as *** MOF-derived heteroatom-doped carbon substrate could be easily obtained by direct pyrolysis of a pre-fabricated rod-like *** optimized ZTB-NSCR-FePc demonstrated exceptional electrocatalytic efficiency and stability towards ORR with a positive half-wave potential of 0.890 *** employed in a Zn-air battery,it outperformed the benchmark Pt/C air cathode,achieving a peak power density of 198.9 mW ***,theoretical calculations revealed that short-range electron interactions between N/S atoms and the graphene substrate significantly enhance the anchoring effect of FePc,improve the adsorption of reaction intermediates,and thereby boost the ORR performance.

关键词： metal-organic framework heteroatom carbon nanorod Fe phthalocyanine oxygen reduction

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A Comprehensive Multifield Coupling Simulation Framework for Broadband Magnetoelectric Antenna Arrays

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IEEE Transactions on Antennas and Propagation 2025年第5期73卷 3146-3155页

作者： Shi, Yang Jiao, Qiyuan Mao, Yue Xidian University Joint Laboratory for International Cooperation in Structural Mechanics of Composite Materials for Electronic Devices School of Mechano-Electronic Engineering Xi’an710071 China

This study developed a comprehensive simulation and analysis framework for magnetoelectric (ME) antenna arrays, seamlessly integrating an equivalent circuit model with a multiphysics coupling model. The resulting model allows for the rapid and effective prediction of the radiation performance of antenna arrays, providing a valuable reference for broadband design initiatives. The research results reveal that by modifying the length of the ME antennas, it is possible to adjust their resonance frequencies effectively while almost maintaining the converse ME (CME) coefficient constant. Furthermore, when the ME antenna units are aligned in parallel to create an array, although there is a slight reduction in the radiation field strength, the 3 dB bandwidth of arrays A and B undergoes a substantial expansion, increasing by 210% and 470%, respectively. Moreover, the radiation performance can be optimized by adjusting the length difference between the antenna elements, thereby achieving the optimal 3 dB bandwidth when the length difference is set to 1.1 mm. © 1963-2012 IEEE.

关键词： Antenna arrays

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