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Science China(Information Sciences) 2024年第6期67卷 328-341页

作者： Xian-Ming zhang qing-Long HAN Bao-Lin zhang Xiaohua GE Dawei zhang School of Science Computingand Engineering TechnologiesSwinburne University of Technology College of Automation and Electronic Engineering Qingdao University of Science & Technology School of Mathematics Shandong University

This paper is concerned with event-triggered H∞control of sampled-data systems. Its novelties lie in three aspects:（i） A novel accumulated-state-error-based event-triggered scheme is introduced by comparing the integral of the state error from tk to t with the system state sampled at tk. This condition works well due to the fact that the so-called Zeno behaviour does not occur.（ii） A novel Lyapunov functional is constructed to establish a criterion to ensure some certain H∞performance of the closed-loop system. This Lyapunov functional is dependent on the integral of the state error involved in the event-triggered scheme.（iii） Under the event-triggered sampling scheme, suitable state-feedback controllers can be designed rather than be given a priori. Moreover, a self-triggered implementation of the proposed event-triggered sampling scheme is presented as well. Finally, a batch reactor model and an inverted pendulum system are given to demonstrate the effectiveness of the proposed method.

关键词： event-triggered sampling self-triggered implementation $H_\infty$ control looped-functional

A Coupled Thermomechanical Crack Propagation Behavior of Brittle Materials by Peridynamic Differential Operator

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Computer Modeling in Engineering & Sciences 2024年第7期140卷 339-361页

作者： Tianyi Li Xin Gu qing zhang College of Architectural Engineering Jiangsu Open UniversityNanjing210036China Department of Engineering Mechanics Hohai UniversityNanjing211100China

This study proposes a comprehensive,coupled thermomechanical model that replaces local spatial derivatives in classical differential thermomechanical equations with nonlocal integral forms derived from the peridynamic differential operator(PDDO),eliminating the need for calibration *** model employs a multi-rate explicit time integration scheme to handle varying time scales in multi-physics *** simulations conducted on granite and ceramic materials,this model demonstrates its *** successfully simulates thermal damage behavior in granite arising from incompatible mineral expansion and accurately calculates thermal crack propagation in ceramic slabs during *** account for material heterogeneity,the model utilizes the Shuffle algorithm andWeibull distribution,yielding results that align with numerical simulations and experimental *** coupled thermomechanical model shows great promise for analyzing intricate thermomechanical phenomena in brittle materials.

关键词： Peridynamic differential operator thermomechanical coupling heterogeneity numerical simulation

Lightweight Malicious Code Classification Method Based on Improved Squeeze Net

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Computers, Materials & Continua 2024年第1期78卷 551-567页

作者： Li Li Youran Kong qing zhang School of Computer and Control Engineering Northeast Forestry UniversityHarbin150040China

With the growth of the Internet,more and more business is being done online,for example,online offices,online education and so *** this makes people’s lives more convenient,it also increases the risk of the network being attacked by malicious ***,it is important to identify malicious codes on computer systems ***,most of the existing malicious code detection methods have two problems:(1)The ability of the model to extract features is weak,resulting in poor model performance.(2)The large scale of model data leads to difficulties deploying on devices with limited ***,this paper proposes a lightweight malicious code identification model Lightweight Malicious Code Classification Method Based on Improved SqueezeNet(LCMISNet).In this paper,the MFire lightweight feature extraction module is constructed by proposing a feature slicing module and a multi-size depthwise separable convolution *** feature slicing module reduces the number of parameters by grouping *** multi-size depthwise separable convolution module reduces the number of parameters and enhances the feature extraction capability by replacing the standard convolution with depthwise separable convolution with different convolution kernel *** addition,this paper also proposes a feature splicing module to connect the MFire lightweight feature extraction module based on the feature reuse and constructs the lightweight model *** malicious code recognition accuracy of LCMISNet on the BIG 2015 dataset and the Malimg dataset reaches 98.90% and 99.58%,*** proves that LCMISNet has a powerful malicious code recognition *** addition,compared with other network models,LCMISNet has better performance,and a lower number of parameters and computations.

关键词： Lightweight neural network malicious code classification feature slicing feature splicing multi-size depthwise separable convolution

Energy absorption behaviors of a novel buffer lander-leg with Yoshimura core

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Chinese Journal of Aeronautics 2024年第4期37卷 333-342页

作者： Yan XU He HUANG Chao zhang Rongji fu School of Aeronautics and Astronautics Zhejiang UniversityHangzhou 310027China School of Mechanics Civil Engineering and Architecture Northwestern Polytechnical UniversityXi’an 710072China

In the current soft-landing system,the lander-leg and the buffer are two independent parts which may cause weight *** traditional mechanical buffers also have their own shortcomings such as small buffer stroke and being non-reusable.A Novel Buffer Lander-leg with Yoshimura core (NBLY) is proposed in this paper,inspired by the Buckling Restrained Brace(BRB).The design details of NBLY and parameter definitions of the core are *** finite element analysis modes have been employed to analyze the nonlinear mechanical behaviors of NBLY subjected to the cyclic *** with four different core styles of hexagon,octagon,dodecagon and hexadecagon are analyzed and *** restraining ratio and cumulative dissipation energy ratio have been obtained to evaluate the energy absorption *** results show that the origami pattern has significant influences on the deformation ductility,plastic energy absorbing and axial load transferring to the *** NBLY with octagon core has outstanding properties,especially the hysteretic energy dissipation and enhancement of compression *** interaction mechanism between the core and encasing member constrains the deformation extensions and contributes to the frictional energy dissipation of the *** paper provides a new conceptual design of buffer lander-leg for soft-landing *** can realize the reuse function as a buffer lander-leg with better loading-bearing and energy absorption behaviors.

关键词： Lander-leg structure Origami Energy absorption Cyclic loading Finite element analysis

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The transition to turbulent fluidization in a gas-solid fluidized bed operating from ambient temperature to 1600℃

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Particuology 2024年第10期93卷 111-124页

作者： qingjin zhang Liangliang fu Guangwen Xu Dingrong Bai Key Laboratory on Resources Chemicals and Material of Ministry of Education Shenyang University of Chemical TechnologyShenyang110142China School of Materials Science and Engineering Shenyang University of TechnologyShenyang110142China Ordos Laboratory Ordos017010China

Turbulent fluidized bed proves effective in industrial processes due to superior heat and mass transfer and chemical reaction performance. However, understanding the transition to turbulent fluidization remains limited, especially at temperatures exceeding 1000 ℃, making it challenging to develop high-temperature fluidized bed applications. This paper presents an experimental investigation on the turbulent fluidization onset velocity (U_(c)), measured in a 30 mm diameter bed using corundum particles with average diameters from 0.68 mm to 1.58 mm in temperatures from ambient to 1600 ℃. Experimental results reveal that U_(c) increases with temperature up to 600 ℃, stabilizes within the 600–1200 ℃ range, and then decreases above 1200 ℃, demonstrating the varying relative significance of hydrodynamic and interparticle forces at different temperatures. To help design and operate high-temperature applications of turbulent fluidization, we developed U_(c) correlations based on experimental data from both literature sources and this study, covering temperatures of up to 1600 ℃ and particles of Groups A to D.

关键词： High-temperature fluidized beds Turbulent fluidization Transition velocity Pressure fluctuations Hydrodynamic forces Interparticle forces

Temperature influence on minimum fluidization velocity:Complexity,mechanism,and solutions

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Particuology 2024年第5期88卷 344-349页

作者： qingjin zhang Liangliang fu Guangwen Xu Dingrong Bai Key Laboratory on Resources Chemicals and Material of Ministry of Education Shenyang University of Chemical TechnologyShenyang 110142China School of Materials Science and Engineering Shenyang University of TechnologyShenyang 110142China School of Chemical Engineering University of Science and Technology LiaoningAnshan 114051China

Fluidized-bed reactors are widely employed in various high-temperature industrial ***,it is crucial to understand the temperature effect on various fluidization phenomena,specifically the minimum fluidization velocity(U_(mf))that governs various aspects of fluidized bed *** this study,we comprehensively analyze U_(mf) data from the literature to unravel the complexity and underlying mechanisms of temperature influence on this critical *** research examines experimental data encompassing a wide range of temperatures,pressures,and solid *** analysis reveals that the influence of temperature on U_(mf) is fundamentally determined by the relative importance of hydrodynamic forces and interparticle forces within fluidized beds and is realized by three distinctive temperature-induced changes:gas properties,bed voidage,and physiochemical characteristics of *** this basis,an equation is derived to enable predictions of temperature influences on the minimum fluidization velocity under broad temperature conditions.

关键词： High-temperature gas-solids fluidized beds Minimum fluidization velocity Hydrodynamic forces Interparticle forces Bed voidage

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晒黄烟不同棚内调制方式对烟叶品质的影响

安徽农业科学 2024年第16期52卷 153-155,210页

作者：喻杰熊橙梁张庆富杨柳李栋宇胡亮亮陈伟明周喜新刘璐湖南省烟草公司长沙市公司宁乡市分公司湖南长沙410600 湖南农业大学生物科学技术学院湖南长沙410128

[目的]提高晒黄烟调制大棚的整体调制效率,以实现更高质量的晒黄烟生产。[方法]通过系统的试验设置探索不同的调制方式。通过监测调制过程中的光照强度和SPAD值,比较不同调制方式晒黄烟的外观品质和化学成分,筛选出优越的调制方式。[结... 详细信息

[目的]提高晒黄烟调制大棚的整体调制效率,以实现更高质量的晒黄烟生产。[方法]通过系统的试验设置探索不同的调制方式。通过监测调制过程中的光照强度和SPAD值,比较不同调制方式晒黄烟的外观品质和化学成分,筛选出优越的调制方式。[结果]晒黄烟调制大棚适宜的调制方式是烟折纵向挂放,晾晒间距为20 cm。该处理接收的光照强度最强,且SPAD值的降解趋势与CK一致。通过这种调制方式,晒黄烟的外观质量表现出叶片结构疏松,表面油润度好,弹性较好,身份适中;烟叶颜色主要分布在正黄到金黄色域,色度均匀,光泽丰满,叶面含青较少。化学成分也呈现出较为理想的状态,总糖(18.8%)、还原糖(14.9%)和钾(1.85%)含量相对较高,而氯离子及氮碱比含量适宜。[结论]该研究结果为晒黄烟调制提供了有力的指导,为实现高效且高质量的晒黄烟生产提供了科学依据。

关键词：晒黄烟调制方式 SPAD值外观质量化学成分

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Dual template-induced construction of three-dimensional porous SiO2/NC/Co-CNTs heterostructure with highly dispersed active sites for efficient oxygen evolution reaction

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Tungsten 2024年第3期6卷 585-595页

作者： Hai-Qi zhang Xiao-Jun Zeng qing-qing zhang Zu-Liang zhang Chu-Long Jin Rong-Hai Yu School of Materials Science and Engineering Jingdezhen Ceramic University School of Materials Science and Engineering Beihang University

The development and exploration of efficient and economical electrocatalysts for oxygen evolution reaction（OER） represents the main bottleneck to unlocking a sustainable energy scenario based on elec trocataly tic water *** scale integration of three-dimensional（3D） porous heterostructure with highly dispersed active sites and good structural stability is ***,a dual template route is developed to construct the 3D porous SiO2/nitrogen-doped carbon（NC）/Co-carbon nano tubes（CNTs） hetero ***,the hard template（SiO2nano spheres） contributes to 3D porous structure,increases the specific surface area,and promotes the contact area of the *** the same time,the soft template（basic zinc carbonate） can control the growth of 1D CNTs and facilitate the exposure of the active ***,3D porous SiO2/NC/Co-CNTs hetero structure inherits highly dispersed Co nanoparticles coated by *** conductive channels and abundant N hetero atoms doping are reasonably constructed by a dual template ***,SiO2/NC/Co-CNTs catalyst provides an extraordinary activity for the OER in alkaline media,with a low overpotential of 298 mV at a current density of 10 mA·***,SiO2/NC/Co-CNTs hetero structure enables excellent long-term durability with a 10 mV decay in overpotential after 3000 cyclic voltammetry cycles,and 97% remain in current density over 20 *** is believed that this dual template strategy can provide a new and simple way to construct a highly dispersed active site in electrocatalysts.

关键词： Dual template High dispersion Porous heterostructure Conductive channels Oxygen evolution reaction

Three-Rigid-Body-Particle Modeling and Optimization of Trajectory and Posture for Alpine Skiing

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Journal of Systems Science & Complexity 2024年第2期37卷 581-608页

作者： zhang Yijia FEI qing YAO Xiaolan SUN Jian zhang Yanjun CHEN Zhen School of Automation Beijing Institute of TechnologyBeijing 100081China

This paper presents a new study on modeling and optimization of trajectory and posture for the super-giant(SG)slalom of alpine *** is the first time that a Three-Rigid-Body-Particle model based on rigorous derivations and stability analysis is established to represent skiers trajectory and posture characteristics,as it is more accurate than the single-rigid-body model which is commonly used in existing *** addition,the Radau pseudospectral method is applied to solve the trajectory and posture optimization problem in order to obtain better skiing trajectory,skiing posture,and some key kinematic parameters of ***,this paper analyzes the effects of different body types,minimum turning radii,and flexor and extensor strength of knees and hip joint on skiing ***,based on the findings of the study,some advice about how to improve the performance of the SG slalom in view of science and technology is given to skiers and coaches for reference.

关键词： Alpine skiing modeling posture optimization Three-Rigid-Body-Particle model trajectory optimization

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Tripartite motif-containing protein 11(TRIM11):a novel weapon against Alzheimer’s disease

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Signal Transduction and Targeted Therapy 2024年第2期9卷 339-340页

作者： Yichu fu Bi zhang Jianfeng Liu College of Life Science and Technology Key Laboratory of Molecular Biophysics of MOEHuazhong University of Science and TechnologyWuhanHubei 430074China

In a recent study published in Science,zhang et *** that tripartite motif-containing(TRIM)protein 11(TRIM11)exhibited strong inhibition on tau aggregation,which is a pathological characteristic of tauopathies including Alzheimer’s disease(AD).1 This makes TRIM11 a promising novel target for the treatment of AD and other tauopathies.

关键词： Alzheimer tau TRIM