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Frontiers of Structural and Civil Engineering 2024年第4期18卷 568-586页

作者： Fu-Wei wu Yuan-Qi li Department of Structural Engineering Tongji UniversityShanghai 200092China State Key Laboratory of Disaster Reduction in Civil Engineering Tongji UniversityShanghai 200092China

The derivation and validation of analytical equations for predicting the tensile initial stiffness of threadfixed one-side bolts(TOBs),connected to enclosed rectangular hollow section(RHS)columns,is presented in this *** unknown stiffness components are considered:the TOBs connection and the enclosed RHS ***,the trapezoidal thread of TOB,as an equivalent cantilevered beam subjected to uniformly distributed loads,is analyzed to determine the associated *** on the findings,the thread-shank serial-parallel stiffness model of TOB connection is *** analysis of the tensile stiffness of the enclosed RHS face due to two bolt forces,the four sidewalls are treated as rotation constraints,thus reducing the problem to a two-dimensional plate *** to the load superposition method,the deflection of the face plate is resolved into three components under various boundary and load *** to the plate deflection theory of Timoshenko,the analytical solutions for the three deflections are derived in terms of the variables of bolt spacing,RHS thickness,height to width ratio,***,the validity of the above stiffness equations is verified by a series of finite element(FE)models of T-stub *** proposed component stiffness equations are an effective supplement to the component-based method.

关键词： initial stiffness component based method thread-fixed one-side bolt rectangular hollow sections analytical equation

Numerical study on local failures of reinforced concrete slabs against underwater close-in explosions

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2024年第8期25卷 650-669页

作者： Fei ZHOU Hedong li Hao wu College of Civil Engineering Tongji UniversityShanghai 200092China School of Civil Engineering and Architecture Zhejiang Sci-Tech UniversityHangzhou 310018China

Reinforced concrete(RC)slabs are the primary load-carrying member of underwater *** can suffer severe local failures such as cratering,spalling,or breaching as a result of underwater close-in(UWCI)*** this study,we established a fully validated high-fidelity finite element analysis approach to precisely reproduce the local failures of RC slabs after a UWCI explosion.A recently proposed dynamic constitutive model is used to describe wet *** effects of free water content on the material properties,including the tensile/compressive strength,elastic modulus,strain rate effect,failure strength surface,and equation of state,are comprehensively calibrated based on existing test *** calibrated material parameters are then verified by a single-element test.A high-fidelity finite element analysis(FEA)approach of an RC slab subjected to a UWCI explosion is established using an arbitrary Lagrangian-Eulerian(ALE)*** previous UWCI explosion tests on RC orifice targets and underwater contact explosion tests on saturated concrete slabs showed that the established FEA approach could accurately reproduce the pressure-time history in water and damage patterns,including the cracking,cratering,and spalling,of the RC orifice target and saturated concrete ***,parametric studies conducted by simulating an RC slab subjected to a UWCI explosion showed that:(i)the local failure of an RC slab enlarges with increased charge weight,reduced standoff distance,and reduced structural thickness;(ii)compared to a water-backed RC slab,an air-backed RC slab exhibits much more obvious local and structural ***,to aid the anti-explosion design of relevant underwater facilities,based on over 90 simulation cases empirical formulae are summarized to predict local failure modes,i.e.,no spall,spall,and breach,of water-and air-backed RC slabs subjected to a UWCI explosion.

关键词： Reinforced concrete slab(RC) Underwater close-in(UWCI)explosion Saturated concrete Failure modes Numerical simulation

Robust textile-based spoof plasmonic frequency scanning antenna for on-body IoT applications

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Science China(Information Sciences) 2024年第8期67卷 269-284页

作者： Zhao-min CHEN Jun-lin ZHAN Hao CHEN Ya li Hongjun HE wu YANG Zhen-Guo liU Wei-Bing LU State Key Lab of Millimeter Waves School of Information Science and EngineeringSoutheast University Center for Flexible RF Technology Frontiers Science Center for Mobile Information Communication and SecuritySoutheast University Future Research Laboratory China Mobile Research Institute Purple Mountain Laboratories

Securing a comfortable, wearable compact frequency beam scanning antenna(FBSA) with robustness to deformation, low specific absorption rate(SAR), and good coverage of the surrounding environment for Internet of Things(IoT) applications, such as on-body navigation and wireless communication is an emerging challenge. In this work, a robust textile-based spoof plasmonic frequency scanning antenna utilizing higher-order modes is presented, which is also robust to deformation caused by the activities of the human body. The innovative design of the element ensures the high-efficiency transmission of the fundamental mode of spoof surface plasmon polaritons(SSPP) structure, providing the potential of being a multifunctional composite device in the compact on-body network. Besides, an artificial magnetic conductor(AMC) is designed underneath the SSPP structure, obtaining a low SAR value(0.113 W/kg), which ensures the safety of users. As a practical realization of this concept, a textile-based spoof plasmonic antenna was fabricated in the microwave regime and the performed experimental results show the proposed antenna has a single-beam radiation characteristic with a 70° beam scanning angle range when the frequency is 4.7–6.0 GHz with a high average realized gain of 13.15 dBi. And it still maintains a steady performance when faced with structure deformation, which proves its robustness. Wireless communication quality experiments are performed to demonstrate the proposed antenna can measure the angles of targets and realize wireless signal transmission to specific targets as the frequency varies, it may find great potential in the field of on-body IoT applications.

关键词： frequency beam scanning antenna (FBSA) Internet of Things (IoT) on-body communication spoof surface plasmon polaritons (SSPP) textile-based antenna

An Improved Northern Goshawk Optimization Algorithm for Feature Selection

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Journal of Bionic Engineering 2024年第4期21卷 2034-2072页

作者： Rongxiang Xie Shaobo li Fengbin wu State Key Laboratory of Public Big Data College of Computer Science and TechnologyGuizhou UniversityGuiyang550025China State Key Laboratory of Public Big Data Guizhou UniversityGuiyang550025China

Feature Selection(FS)is an important data management technique that aims to minimize redundant information in a *** work proposes DENGO,an improved version of the Northern Goshawk Optimization(NGO),to address the FS *** NGO is an efficient swarm-based algorithm that takes its inspiration from the predatory actions of the northern *** order to overcome the disadvantages that NGO is prone to local optimum trap,slow convergence speed and low convergence accuracy,two strategies are introduced in the original NGO to boost the effectiveness of ***,a learning strategy is proposed where search members learn by learning from the information gaps of other members of the population to enhance the algorithm's global search ability while improving the population ***,a hybrid differential strategy is proposed to improve the capability of the algorithm to escape from the trap of the local optimum by perturbing the individuals to improve convergence accuracy and *** prove the effectiveness of the suggested DENGO,it is measured against eleven advanced algorithms on the CEC2015 and CEC2017 benchmark functions,and the obtained results demonstrate that the DENGO has a stronger global exploration capability with higher convergence performance and ***,the proposed DENGO is used for FS,and the 29 benchmark datasets from the UCL database prove that the DENGO-based FS method equipped with higher classification accuracy and stability compared with eight other popular FS methods,and therefore,DENGO is considered to be one of the most prospective FS ***'s code can be obtained at https://***/matlabcentral/fileexchange/158811-project1.

关键词： Northern goshawk optimization Learning strategy Hybrid differential strategy Numerical optimization Feature selection

Flexible printed three dimensional(3D) integrated carbon nanotube complementary metal oxide semiconductor(CMOS) thin film transistors and circuits

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Science China(Information Sciences) 2024年第09期67卷 280-293页

作者： Zhaofeng CHEN Jiaqi li min li Hongxuan GUO Jianwen ZHAO SEU-FEI Nano-Pico Center Key Laboratory of MEMS of Ministry of Education Southeast University Printable Electronics Research Center Division of Nanodevices and Related NanomaterialsSuzhou Institute of Nano-Tech and Nano-Bionics Chinese Academy of Sciences School of Nano Technology and Nano Bionics University of Science and Technology of China

The threshold voltage modulation of carbon nanotube thin-film transistors（TFTs） and flexible three-dimensional（3D） integration circuits has become hot research topics for carbon-based electronics. In this paper, a doping-free gate electrode technology is introduced to significantly modulate the threshold voltage of polymer-sorted semiconducting single-walled carbon nanotube（sc-SWCNT） TFTs in combination with the highly effective gate-controlling ability of solid-state electrolyte thin films as the dielectrics. A systematic investigation was conducted on the impact of printed silver, evaporated silver, and evaporated aluminum（Al） gate electrodes on the threshold voltage of flexible printed bottom-gate and top-gate SWCNT TFTs. The results indicate that the SWCNT TFTs with Al gate electrodes exhibit enhancement-mode characteristics with excellent electrical properties, such as the negative threshold voltages（-0.6 V）, high Ion/Ioff（up to 10～6）, low subthreshold swing(61.4 mV · dec-1), and small hysteresis. It is attributed to either the formation of lower work function thin films（Al2O3） at the electrode/dielectric layer interfaces through the natural oxidation of the Al bottom-gate electrodes or the dipole reaction of the Al top-gate electrodes from X-ray photoelectron spectroscopy（XPS） and ultraviolet photoelectron spectroscopy（UPS） data. In addition, 3D complementary metal-oxide-semiconductor（CMOS） inverters with common gate electrodes were constructed using the resulting enhancement-mode P-type SWCNT TFTs and matched N-type SWCNT TFTs, which shows high voltage gain（34）, rail-to-rail output and high noise margins(80.04%, VDD=-1 V)as well good mechanical flexibility at low operation voltages. It demonstrates that SWCNT TFTs have great advantages for building large-scale 3D flexible integrated circuits.

关键词： three-dimensional CMOS circuits printing technology polymer-sorted semiconducting carbon nanotubes enhancement-mode thin-filmtransistors threshold voltage modulation

State-Based Opacity Verification of Networked Discrete Event Systems Using Labeled Petri Nets

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IEEE/CAA Journal of Automatica Sinica 2024年第5期11卷 1274-1291页

作者： Yifan Dong Naiqi wu Zhiwu li The authors are with the Institute of Systems Engineering Macao University of Science and TechnologyTaipa 999078MacaoChina

The opaque property plays an important role in the operation of a security-critical system,implying that pre-defined secret information of the system is not able to be inferred through partially observing its *** paper addresses the verification of current-state,initial-state,infinite-step,and K-step opacity of networked discrete event systems modeled by labeled Petri nets,where communication losses and delays are *** on the symbolic technique for the representation of states in Petri nets,an observer and an estimator are designed for the verification of current-state and initial-state opacity,***,we propose a structure called an I-observer that is combined with secret states to verify whether a networked discrete event system is infinite-step opaque or K-step *** to the utilization of symbolic approaches for the state-based opacity verification,the computation of the reachability graphs of labeled Petri nets is avoided,which dramatically reduces the computational overheads stemming from networked discrete event systems.

关键词： infinite system symbolic

Anesthesia,Anesthetics,and Postoperative Cognitive Dysfunction in Elderly Patients

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Current Medical Science 2024年第2期44卷 291-297页

作者： Hong-yu ZHU Jian-li YAN min ZHANG Tian-yun XU Chen CHEN Zhi-lin wu Department of Anesthesiology Linhe District People's HospitalBayannur 015000China Department of Neurosurgery Xinzhou District People's HospitalWuhan 430408China Department of Anesthesiology Union HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430022China

Postoperative cognitive dysfunction(POCD)remains a major issue that worsens the prognosis of elderly surgery *** article reviews the current research on the effect of different anesthesia methods and commonly utilized anesthetics on the incidence of POCD in elderly patients,aiming to provide an understanding of the underlying mechanisms contributing to this condition and facilitate the development of more reasonable anesthesia protocols,ultimately reducing the incidence of POCD in elderly surgery patients.

关键词： anesthesia anesthetics postoperative cognitive dysfunction elderly patients

VPD modifies CO_(2)fertilization effect on tomato plants via abscisic acid and jasmonic acid signaling pathways

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Horticultural Plant Journal 2024年第5期10卷 1165-1176页

作者： Dalong Zhang Huihua Yang Xiaolu Chen Yan li Yunzhou li Hongye liu Xulin wu min Wei College of Horticultural Science and Engineering Shandong Agricultural UniversityTai'anShandong 271018China College of Agriculture Guizhou UniversityGuiyangGuizhou 550025China

Atmospheric CO_(2)concentration is elevated globally,which has“CO_(2)fertilization effects”and potentially improves plant photosynthesis,yield,and *** the beneficial effect of CO_(2)fertilization being modulated by vapor pressure deficit(VPD),the underlying mechanism is highly *** the present study,the potential roles of hormones in determining CO_(2)fertilization effects under contrasting high and low VPD conditions were investigated by integrated physiological and transcriptomic *** CO_(2)fertilization effects were offset under high VPD conditions and were constrained by plant water stress and photosynthetic CO_(2)*** VPD induced a large passive water driving force,which disrupted the water balance and consequently caused plant water *** water potential,turgor pressure,and hydraulic conductance declined under high VPD *** physiological evidence combined with transcriptomic analyses demonstrated that abscisic acid(ABA)and jasmonic acid(JA)potentially acted as drought-signaling molecules in response to high VPD *** foliar ABA and JA content triggered stomatal closure to prevent excessive water loss under high VPD stress,which simultaneously increased the diffusion resistance for CO_(2)uptake from atmosphere to leaf intercellular *** VPD also significantly increased mesophyll resistance for CO_(2)transport from stomatal cavity to fixation site inside *** chloroplast“sink”CO_(2)availability was constrained by stomatal and mesophyll resistance under high VPD stress,despite the atmospheric“source”CO_(2)concentration being ***,ABA-and JA-mediated drought-resistant mechanisms potentially modified the beneficial effect of CO_(2)fertilization on photosynthesis,plant growth,and yield *** study provides valuable information for improving the utilization efficiency of CO_(2)fertilization and a better understanding of the physiological processes.

关键词： Abscisic acid CO_(2)fertilization Jasmonic acid Mesophyll conductance Stomatal conductance Vapor pressure deficit

Influence mechanism of government subsidy on the green transformation of coal company in China

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International Journal of mining Science and Technology 2024年第7期34卷 1033-1040页

作者： li, Xiaolei wu, Changsong School of Management China University of Mining and Technology - Beijing Beijing 100083 China School of Economics and Management China University of Mining and Technology Xuzhou 221116 China

The optimization of government subsidies to enhance the efficiency of coal companies’ green transformation constitutes a critical component in the pursuit of global sustainability. We investigate the influence mechanism of government subsidies on the green transformation using data from the listed coal companies in China from 2007 to 2022. According to our findings and hypothesis testing, previous government subsidies did not have a significant direct impact on coal companies’ green transformation. Nevertheless, government subsidies can help coal companies transition to greener practices by promoting innovative green initiatives. Furthermore, we confirmed an indirect route: that government subsidies enable the adoption of low-carbon initiatives, which in turn could facilitate the transition of coal companies towards green practices. In addition, we discovered that the coal company's digitization will improve this indirect route. Thus, we propose increasing the effectiveness of government subsidies in facilitating coal companies’ transition to green practices by focusing on technological advancements and enhancing company digitalization. © 2024

关键词： Green development

Research on fast detection method of infrared small targets under resource-constrained conditions

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JOURNAL OF INFRARED AND MILliMETER WAVES 2024年第4期43卷 582-587页

作者： Zhang, Rui liu, min li, Zheng Xiamen Univ Technol Sch Optoelect & Comunicat Engn Xiamen 361024 Peoples R China Chinese Acad Sci Shanghai Inst Tech Phys Shanghai 200083 Peoples R China

Infrared small target detection is a common task in infrared image processing. Under limited computational resources. Traditional methods for infrared small target detection face a trade-off between the detection rate and the accuracy. A fast infrared small target detection method tailored for resource-constrained conditions is proposed for the YOLOv5s model. This method introduces an additional small target detection head and replaces the original Intersection over Union (IoU) metric with Normalized Wasserstein Distance (NWD), while considering both the detection accuracy and the detection speed of infrared small targets. Experimental results demonstrate that the proposed algorithm achieves a maximum effective detection speed of 95 FPS on a 15 W TPU, while reaching a maximum effective detection accuracy of 91. 9 AP@0.5, effectively improving the efficiency of infrared small target detection under resource-constrained conditions.

关键词： infrared UAV image fast small object detection low impedance loss function