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A six-variable quasi-3D isogeometric approach for free vibration of functionally graded graphene origami-enabled auxetic metamaterial plates submerged in a fluid medium

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Applied Mathematics and Mechanics(English Edition) 2025年第1期46卷 157-176页

作者： Wei CHEN Zhihong TANG Yufen LIAO Linxin PENG College of Civil engineering University of South China College of Civil engineering and Architecture Guangxi University key laboratory of disaster prevention and Structural safety of Ministry of Education Guangxi University

This paper presents, for the first time, an effective numerical approach based on the isogeometric analysis(IGA) and the six-variable quasi-three dimensional(3D)higher-order shear deformation theory(HSDT) to study the free vibration characteristics of functionally-graded(FG) graphene origami(GOri)-enabled auxetic metamaterial(GOEAM) plates submerged in a fluid medium. The plate theory incorporates the thickness stretching and the effects of transverse shear deformation without using any shear correction factors. The velocity potential function and Bernoulli's equation are used to derive the hydrodynamic pressure acting on the plate surface. Both horizontally and vertically immersed plate configurations are considered here in the form of inertia *** plates are composed of multilayer GOEAMs, with the GOri content varying through the plate's thickness in a layer-wise manner. This design results in graded auxetic *** material properties are evaluated by mixing rules and a genetic programming(GP)-assisted micromechanical model. The governing equations of motion for the FG-GOEAM plates immersed in a fluid medium are derived by Hamilton's principle. After validating the convergence and accuracy of the present model, a comprehensive parametric study is carried out to examine the effects of the GOri content, GOri distribution pattern, GOri folding degree, fluid level, immersed depth, and geometric parameter on the natural frequencies of the FG-GOEAM plates. The results show that the natural frequencies for the four GOri distribution patterns increase with the increase in the layer number when the lay number is fewer than 10, and then stabilize after the layer number reaches ***, in general, the natural frequency of the FG-GOEAM plate in a vacuum or fluid increases when the GOri content increases, while decreases when the GOri folding degree increases. Some additional findings related to the numerical results are presented in the conclusions. It is belie

关键词： free vibration functionally-graded (FG) graphene origami (GOri)-enabled auxetic metamaterial (GOEAM) plate hydrodynamic pressure isogeometric analysis (IGA) O321 quasi-three dimensional (3D) higher-order shear deformation theory (HSDT)

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DDoS Attack Autonomous Detection Model Based on Multi-Strategy Integrate Zebra Optimization Algorithm

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Computers, Materials & Continua 2025年第1期82卷 645-674页

作者： Chunhui Li Xiaoying Wang Qingjie Zhang Jiaye Liang Aijing Zhang School of Information engineering Institute of Disaster PreventionLangfang065201China Langfang key laboratory of Network Emergency Protection and Network Security Langfang065201China

Previous studies have shown that deep learning is very effective in detecting known ***,when facing unknown attacks,models such as Deep Neural Networks(DNN)combined with Long Short-Term Memory(LSTM),Convolutional Neural Networks(CNN)combined with LSTM,and so on are built by simple stacking,which has the problems of feature loss,low efficiency,and low ***,this paper proposes an autonomous detectionmodel for Distributed Denial of Service attacks,Multi-Scale Convolutional Neural Network-Bidirectional Gated Recurrent Units-Single Headed Attention(MSCNN-BiGRU-SHA),which is based on a Multistrategy Integrated Zebra Optimization Algorithm(MI-ZOA).The model undergoes training and testing with the CICDDoS2019 dataset,and its performance is evaluated on a new GINKS2023 *** hyperparameters for Conv_filter and GRU_unit are optimized using the Multi-strategy Integrated Zebra Optimization Algorithm(MIZOA).The experimental results show that the test accuracy of the MSCNN-BiGRU-SHA model based on the MIZOA proposed in this paper is as high as 0.9971 in the CICDDoS 2019 *** evaluation accuracy of the new dataset GINKS2023 created in this paper is *** to the MSCNN-BiGRU-SHA model based on the Zebra Optimization Algorithm(ZOA),the detection accuracy on the GINKS2023 dataset has improved by 5.81%,precisionhas increasedby 1.35%,the recallhas improvedby 9%,and theF1scorehas increasedby 5.55%.Compared to the MSCNN-BiGRU-SHA models developed using Grid Search,Random Search,and Bayesian Optimization,the MSCNN-BiGRU-SHA model optimized with the MI-ZOA exhibits better performance in terms of accuracy,precision,recall,and F1 score.

关键词： Distributed denial of service attack intrusion detection deep learning zebra optimization algorithm multi-strategy integrated zebra optimization algorithm

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Atomic cerium-doped CuO_(x) catalysts for efficient electrocatalytic CO_(2) reduction to CH_(4)

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Chinese Chemical Letters 2025年第1期36卷 326-331页

作者： Xiangyu Chen Aihao Xu Dong Wei Fang Huang Junjie Ma Huibing He Jing Xu guangxi key laboratory of Petrochemical Resource Processing and Process Intensification Technology School of Chemistry and Chemical EngineeringGuangxi UniversityNanning 530004China State key laboratory of Featured Metal Materials and Life-cycle safety for Composite Structures Guangxi UniversityNanning 530004China State key laboratory of Green Chemical engineering and Industrial Catalysis School of Chemical EngineeringEast China University of Science and TechnologyShanghai 200237China

Copper(Cu)is widely used in the electrochemical carbon dioxide reduction reaction(ECO_(2)RR)for efficient methane(CH_(4))***,the morphology and valence of Cu-based catalysts are usually unstable under reaction *** this work,we prepared Ce-doped MOF-199 precursor(Ce/HKUST-1)and further obtained nanoparticle electrocatalyst Ce/CuO_(x)-NPs by cyclic voltammetry(CV)*** Faradic efficiency of methane(FE_(CH_(4)))maintains above 62%within a broad potential window of 350 mV and the maximum FE_(CH_(4))reaches 67.4%with a partial current density of 293 mA/cm^(2)at-1.6 V vs.a reversible hydrogen *** characterization and theoretical calculations revealed that the unique electronic structure and large ionic radius of Cerium(Ce)not only promoted the generation of key intermediate*CO but also lowered energy barrier of the*CO to*CHO *** study provides a novel and efficient catalyst for methane production in ECO_(2)RR and offers profound insights into constructing high performance Cu-based catalysts.

关键词： ECO_(2)RR Cu-based catalyst Structure evolution DFT calculation

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Experimental and numerical simulation of the attenuation effect of blast shock waves in tunnels at different altitudes

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Defence Technology(防务技术) 2025年第1期43卷 120-141页

作者： Changjiang Liu Hujun Li Zhen Wang Yong He Guokai Zhang Mingyang Wang School of Mechanical engineering Nanjing University of Science and TechnologyNanjing 210094China State key laboratory of disaster prevention and Mitigation of Explosion and Impact People's Liberation Army Engineering UniversityNanjing 210014China

Traffic engineering such as tunnels in various altitudinal gradient zone are at risk of accidental explosion,which can damage personnel and *** prediction of the distribution pattern of explosive loads and shock wave propagation process in semi-enclosed structures at various altitude environment is key research focus in the fields of explosion shock and fluid *** effect of altitude on the propagation of shock waves in tunnels was investigated by conducting explosion test and numerical *** on the experimental and numerical simulation results,a prediction model for the attenuation of the peak overpressure of tunnel shock waves at different altitudes was *** results showed that the peak overpressure decreased at the same measurement points in the tunnel entrance under the high altitude *** contrast,an increase in altitude accelerated the propagation speed of the shock wave in the *** average error between the peak shock wave overpressure obtained using the overpressure prediction formula and the measured test data was less than15%,the average error between the propagation velocity of shock waves predicted values and the test data is less than 10%.The method can effectively predict the overpressure attenuation of blast wave in tunnel at various altitudes.

关键词： Shock wave propagation Tunnel Altitude effect Peak overpressure Shock waves velocity engineering safety

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Influence of material characteristics on the failure mode and process of landslide dam

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Journal of Mountain Science 2025年第1期22卷 89-109页

作者： HU Liang ZHONG Qiming CHEN Liang YANG Meng ZHANG Lucheng WU Hao College of Civil and Transportation engineering Hohai UniversityNanjing 210098China Department of Geotechnical engineering Nanjing Hydraulic Research Institute National key laboratory of Water disaster prevention Nanjing 210098China key laboratory of Reservoir and Dam safety of the Ministry of Water Resources Nanjing 210029China

Landslide dams,as frequent natural hazards,pose significant risks to human lives,property,and ecological *** grading characteristics and density of dam materials play a crucial role in determining the stability of landslide dams and the potential for dam *** explore the failure mechanisms and evolutionary processes of landslide dams with varying soil properties,this study conducted a series of flume experiments,considering different grain compositions and material *** results demonstrated that grading characteristics significantly influence landslide dam stability,affecting failure patterns,breach processes,and final breach ***-graded materials exhibited a sequence of surface erosion,head-cut erosion,and subsequent surface erosion during the breach process,while well-graded materials typically experienced head-cut erosion followed by surface *** coarse-graded dams,the high permeability of coarse particles allowed the dam to remain stable,as inflows matched *** dam breach model experiments also showed that increasing material density effectively delayed the breach and reduced peak breach flow ***,higher fine particle content led to a reduction in the residual dam height and the base slope of the final breach profile,although the relationship between peak breach discharge and the content of fine and coarse particles was *** better understand breach morphology evolution under different soil characteristics and hydraulic conditions,three key points were identified—erosion point,control point,and scouring *** study,by examining the evolution of failure patterns,breach processes,and breach flow discharges under various grading and density conditions,offers valuable insights into the mechanisms behind landslide dam failures.

关键词： Landslide dams Overtopping Grain size distribution Breaching process Outflow discharge

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Investigation on coal damage and fracture extension law of liquid nitrogen injection pre-cooling and fracturing under true triaxial stress

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International Journal of Mining Science and Technology 2025年第2期35卷 213-229页

作者： Botao Li Haifei Lin Jianping Wei Hongtu Zhang Shugang Li Zongyong Wei Lei Qin Pei Wang Rongwei Luo Zeran Liu School of safety Science and engineering Henan Polytechnic UniversityJiaozuo 454003China State key laboratory Cultivation Base for Gas Geology and Gas Control Henan Polytechnic UniversityJiaozuo 454003China State Collaborative Innovation Center of Coal Work safety and Clean-efficiency Utilization Henan Polytechnic UniversityJiaozuo 454003China College of safety Science and engineering Xi’an University of Science and TechnologyXi’an 710054China key laboratory of Shaanxi Province Universities of Gas disaster prevention and Control in Western Coal Mines Xi’an 710054China

To more accurately describe the coal damage and fracture evolution law during liquid nitrogen(LN_(2))fracturing under true triaxial stress,a thermal-hydraulic-mechanical-damage(THMD)coupling model for LN_(2) fracturing coal was developed,considering the coal heterogeneity and thermophysical parameters of *** accuracy and applicability of model were verified by comparing with LN_(2) injection pre-cooling and fracturing experimental *** effects of different pre-cooling times and horizontal stress ratios on coal damage evolution,permeability,temperature distribution,and fracture characteristics were *** results show that the permeability and damage of the coal increase exponentially,while the temperature decreases exponentially during the fracturing *** the pre-cooling time increases,the damage range of the coal expands,and the fracture propagation becomes more *** initiation pressure and rupture pressure decrease and tend to stabilize with longer precooling *** the horizontal stress ratio increases,fractures preferentially extend along the direction of maximum horizontal principal stress,leading to a significant decrease in both initiation and rupture *** a horizontal stress ratio of 3,the initiation pressure drops by 48.07%,and the rupture pressure decreases by 41.36%.The results provide a theoretical basis for optimizing LN_(2) fracturing techniques and improving coal seam modification.

关键词： Liquid nitrogen fracturing Thermal–hydraulic-mechanical-damage coupling Heterogeneous coal True triaxial stress Fracture morphology

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Prediction of time-energy-location of microseismic events induced by deep coal-energy mining:Deep learning approach

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Journal of Rock Mechanics and Geotechnical engineering 2025年第1期17卷 233-244页

作者： Yue Song Enyuan Wang Hengze Yang Dong Chen Baolin Li Yangyang Di School of safety engineering China University of Mining and TechnologyXuzhou221116China State key laboratory of Coal Mine disaster prevention and Control China University of Mining and TechnologyXuzhou221116China State key laboratory for Geomechanics&Deep Underground engineering China University of Mining TechnologyXuzhou221116China School of Environment and safety engineering North University of ChinaTaiyuan030051China School of Materials engineering Changshu Institute of TechnologySuzhou215506China

Deep coal-energy mining frequently results in microseismic(MS)events,which may be a precursor to the risk of rockbursts and pose risks to human safety and ***,quantitatively predicting the time,energy,and location(TEL)of future MS events is crucial for understanding and preventing potential catastrophic *** this study,we introduced the application of spatiotemporal graph convolutional networks(STGCN)to predict the TEL of MS events induced by deep coal-energy ***,this was the first application of graph convolution networks(GCNs)in the spatiotemporal prediction of MS *** adjacency matrices of the sensor networks were determined based on the distance between MS sensors,the sensor network graphs we constructed,and GCN was employed to extract the spatiotemporal details of the *** model is simple and *** testing the model with on-site MS monitoring data,our results demonstrated promising efficacy in predicting the TEL of MS events,with the cosine similarity(C)above 0.90 and the mean relative error(MRE)below *** is critical to improving the safety and operational efficiency of deep coal-energy mining.

关键词： Rockburst Microseismic system Monitoring and early warning Artificial intelligence

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Influence mechanism and calculation of the minimum safe thickness of waterproof rock mass in karst tunnels

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Journal of Mountain Science 2025年第2期22卷 695-709页

作者： AN Pengtao LI Maoxiang ZHANG Wenjun LIU Xiong guangxi University Nanning 530000China State key laboratory of Featured Metal Materials and Life-cycle safety for Composite Structures Guangxi UniversityNanning 530000China

Due to the influence of karst cave development and route selection,the location relationship between concealed karst cave and tunnel is more *** order to explore the influence rule of karst cave location on the minimum safe thickness of water-proof rock mass,a simplified calculation model of water-proof rock mass thickness when the karst cave is located at any location around the tunnel is established,and the influence of multiple factors on the overall stability of water-proof rock mass is *** on the cusp catastrophe theory,the analytical expressions for the safety thickness of waterproof rock mass are *** on the finite difference principle,the analytical expressions of the safety thickness of water-proof rock mass are *** order to improve the application range of the analytical formula derived in this paper,the analytical formula is optimized based on the instability principle differences between the simplified calculation model and the elastic compressive *** research results show that the necessary condition solution is more applicable and much safer than the sufficient condition *** stress,rock beam length and karst cave water pressure are significantly positively correlated with the safe thickness of the waterproof rock *** calculated results of the semioptimized formula and the unoptimized formula are constant values,independent of the karst cave *** the calculated results of the fully optimized formula are variable values,correlated with the karst cave location,the thickness of the waterproof rock mass gradually decreases as the karst cave location moves from the top of the tunnel to the bottom of the *** unoptimized formula does not consider the influence of the lateral force of the rock beam,and is not suitable for the working condition with large lateral force,the calculation results of the semi-optimized formula and the fully optimized formula are not very different and are bia

关键词： Tunnel engineering Water inrush disaster Safe thickness Waterproof rock mass Concealed karst cave

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Modification of Maxwell model for conductivity prediction of carbon nanotubes-filled polymer composites with tunneling effect

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Applied Mathematics and Mechanics(English Edition) 2025年第1期46卷 25-36页

作者： Jue ZHU Longyuan LI Ningtao ZHU Zhejiang Provincial engineering Research Center for the safety of Pressure Vessel and Pipeline key laboratory of Impact and safety engineering (Ningbo University) Ministry of Education School of engineering Computing and Mathematics University of Plymouth Xi'an Zhanshi Testing & engineering Co.Ltd.

Carbon nanotubes(CNTs) have garnered great attention in recent years due to their outstanding electrical, thermal, and mechanical properties. The incorporation of small amounts of CNTs in polymers can substantially improve the sensitivity of the polymer's electrical conductivity. This paper presents a modified Maxwell model to evaluate the electrical conductivity of CNTs-filled polymer composites by introducing a transition zone to account for the tunneling effect. In this modified Maxwell model, the CNTs-filled polymer composite is modeled as a three-phase composite, consisting of a matrix(polymer), inclusions(CNTs), and a transition zone(tunneling zone). The effective electrical conductivity(EEC) of the composite is calculated based on the volume fractions and electrical conductivities of the matrix, inclusions, and transition zone. The model's validity is confirmed through the use of available test data, which demonstrates its capability to accurately capture the nonlinear conductivity behavior observed in CNTs-polymer composites. This study offers valuable insights into the design of high-performance conductive polymer nanocomposites, and enhances the understanding of electrical conduction mechanisms in CNT-dispersed polymer composites.

关键词： carbon nanotube (CNT) composite electrical conductivity Maxwell model O242.2 O441.1 polymer tunneling

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Experimental investigation on the anti-detonation performance of composite structure containing foam geopolymer backfill material

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Defence Technology(防务技术) 2025年第1期43卷 304-318页

作者： Hang Zhou Hujun Li Zhen Wang Dongming Yan Wenxin Wang Guokai Zhang Zirui Cheng Song Sun Mingyang Wang School of Mechanical engineering Nanjing University of Science and TechnologyNanjing 210094China College of Civil engineering and Architecture Zhejiang UniversityHangzhou 310058China Institute for Composites Science Innovation School of Materials Science and EngineeringZhejiang UniversityHangzhou310027China School of safety Science and engineering(School of Emergency Management) Nanjing University of Science and TechnologyNanjing 210094China State key laboratory of disaster prevention and Mitigation of Explosion and Impact Army Engineering University of PLANanjing 210014China

The compression and energy absorption properties of foam geopolymers increase stress wave attenuation under explosion impacts,reducing the vibration effect on the *** tests were conducted using several composite structure models,including a concrete lining structure(CLS)without foam geopolymer and six foam geopolymer composite structures(FGCS)with different backfill parameters,to study the dynamic response and wave dissipation mechanisms of FGCS under explosive ***,strain,and vibration responses at different locations were synchronously *** damage modes and dynamic responses of different models were compared,and how wave elimination and energy absorption efficiencies were affected by foam geopolymer backfill parameters was *** results showed that the foam geopolymer absorbed and dissipated the impact energy through continuous compressive deformation under high strain rates and dynamic loading,reducing the strain in the liner structure by 52%and increasing the pressure attenuation rate by 28%.Additionally,the foam geopolymer backfill reduced structural vibration and liner deformation,with the FGCS structure showing 35%less displacement and 70%less acceleration compared to the *** FGCS model with thicker,less dense foam geopolymer backfill,having more pores and higher porosity,demonstrated better compression and energy absorption under dynamic impact,increasing stress wave attenuation *** analyzing the stress wave propagation and the compression characteristics of the porous medium,it was concluded that the stress transfer ratio of FGCS-ρ-579 was 77%lower than that of CLS,and the transmitted wave energy was 90%*** results of this study provide a scientific basis for optimizing underground composite structure interlayer parameters.

关键词： Explosion load Composite structure Geopolymer foam Energy absorption

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