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Cellular Automata-based Chloride Ion Diffusion Simulation of Concrete Bridges under Multi-factor Coupling Actions 被引量:2
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作者 ZHU Jinsong HE Likun 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2012年第1期160-165,共6页
In order to accurately simulate the diffusion of chloride ion in the existing concrete bridge and acquire the precise chloride ion concentration at given time, a cellular automata (CA)-based model is proposed. The p... In order to accurately simulate the diffusion of chloride ion in the existing concrete bridge and acquire the precise chloride ion concentration at given time, a cellular automata (CA)-based model is proposed. The process of chloride ion diffusion is analyzed by the CA-based method and a nonlinear solution of the Fick's second law is obtained. Considering the impact of various factors such as stress states, temporal and spatial variability of diffusion parameters and water-cement ratio on the process of chloride ion diffusion, the model of chloride ion diffusion under multi-factor coupling actions is presented. A chloride ion penetrating experiment reported in the literature is used to prove the effectiveness and reasonability of the present method, and a T-type beam is taken as an illustrative example to analyze the process of chloride ion diffusion in practical application. The results indicate that CA-based method can simulate the diffusion of chloride ion in the concrete structures with acceptable precision. 展开更多
关键词 concrete bridge chloride ion diffusion cellular automata multi-factor coupling actions
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Numerical Study of Multi-Factor Coupling Effects on Energy Conversion Performance of Nanofluidic Reverse Electrodialysis
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作者 Hao Li Cunlu Zhao +4 位作者 Jinhui Zhou Jun Zhang Hui Wang Yanmei Jiao Yugang Zhao 《Frontiers in Heat and Mass Transfer》 2025年第2期507-528,共22页
Based on the rapid advancements in nanomaterials and nanotechnology,the Nanofluidic Reverse Electrodialysis(NRED)has attracted significant attention as an innovative and promising energy conversion strategy for extrac... Based on the rapid advancements in nanomaterials and nanotechnology,the Nanofluidic Reverse Electrodialysis(NRED)has attracted significant attention as an innovative and promising energy conversion strategy for extracting sustainable and clean energy fromthe salinity gradient energy.However,the scarcity of research investigating the intricate multi-factor coupling effects on the energy conversion performance,especially the trade-offs between ion selectivity and mass transfer in nanochannels,of NRED poses a great challenge to achieving breakthroughs in energy conversion processes.This numerical study innovatively investigates the multi-factor coupling effect of three critical operational factors,including the nanochannel configuration,the temperature field,and the concentration difference,on the energy conversion processes of NRED.In this work,a dimensionless amplitude parameter s is introduced to emulate the randomly varied wall configuration of nanochannels that inherently occur in practical applications,thereby enhancing the realism and applicability of our analysis.Numerical results reveal that the application of a temperature gradient,which is oriented in opposition to the concentration gradient,enhances the ion transportation and selectivity simultaneously,leading to an enhancement in both output power and energy conversion efficiency.Additionally,the increased fluctuation of the nanochannel wall from s=0 to s=0.08 improves ion selectivity yet raises ion transport resistance,resulting in an enhancement in output power and energy conversion efficiency but a slight reduction in current.Furthermore,with increasing the concentration ratio cH/cL from 10 to 1000,either within a fixed temperature field or at a constant dimensionless amplitude,the maximumpower consistently attains its optimal value at a concentration ratio of 100 but the cation transfer number experiences amonotonic decrease across this entire range of concentration ratios.Finally,uponmodifying the operational parameters fromthe baseline condition of s=0,c_(H)/c_(L)=10,andΔT=0 K to the targetedconditionof s=0.08,c_(H)/c_(L)=50,andΔT=25 K,there is a concerted improvement observed in the open-circuit potential,short-circuit current,andmaximumpower,with respective increments of 8.86%,204.97%,and 232.01%,but a reduction in cation transfer number with a notable decrease of 15.37%. 展开更多
关键词 Salinity gradient energy nanofluidic reverse electrodialysis energy conversion nanochannel configuration multi-factor coupling effect
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Safety modeling and simulation of multi-factor coupling heavy-equipment airdrop 被引量:8
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作者 Zhang Jiuxing Xu Haojun +1 位作者 Zhang Dengcheng Liu Dongliang 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2014年第5期1062-1069,共8页
Heavy-equipment airdrop is a highly risky procedure that has a complicated system due to the secluded and complex nature of factors' coupling. As a result, it is difficult to study the modeling and safety simulation ... Heavy-equipment airdrop is a highly risky procedure that has a complicated system due to the secluded and complex nature of factors' coupling. As a result, it is difficult to study the modeling and safety simulation of this system. The dynamic model of the heavy-equipment airdrop is based on the Lagrange analytical mechanics, which has all the degrees of freedom and can accurately pinpoint the real-time coordinates and attitude of the carrier with its cargo. Unfavorable conditions accounted in the factors' models, including aircraft malfunctions and adverse environments, are established from a man-machine-environment perspective. Subsequently, a virtual simulation system for the safety research of the multi-factor coupling heavy-equipment airdrop is developed through MATLAB/Simulink, C language and Flightgear software. To verify the veracity of the theory, the verification model is built based on dynamic software ADAMS. Finally, the emulation is put to the test with the input of realistic accident variables to ascertain its feasibility and validity of this method. 展开更多
关键词 Heavy-equipment airdrop Modeling and simulation Multi-body system multi-factor coupling Safety
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Coupling action of rainfall and vehicle loads impact on the stability of loess slopes based on the iso-water content layer 被引量:3
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作者 Yu Zhang Hongjian Jiang +1 位作者 Gexue Bai Bingbing Han 《Earthquake Research Advances》 CSCD 2022年第3期67-76,共10页
To clarify the changes in slope stability of loess slopes under the coupling action of rainfall and vehicle loads.Experiments with different water contents under different environmental conditions were carried out ind... To clarify the changes in slope stability of loess slopes under the coupling action of rainfall and vehicle loads.Experiments with different water contents under different environmental conditions were carried out indoors,and the relationship function between water content and shear strength parameters was obtained;based on Geostudio,an equivalent layered calculation model of water content-strength parameters of loess slope was established,the variation law of soil sample matrix suction with volumetric water content was measured by volumetric pressure plate tester.Finally,by using a combination of finite element analysis of saturated/unsatu-rated seepage and limit equilibrium analysis of slope stability,the SLOPE/W module in the modeling software GeoStudio is used to calculate and analyze the effects of vehicle loads,rainfall intensity,rainfall duration,and other working conditions on the stability of loess slopes,respectively.The results show that when the lane is in the middle of the slope,the vehicle load parameters have little effect on the uphill stability,but have a greater impact on the downhill;With the increase in rainfall,the change curves of the slope safety coefficient gradually overlap when the vehicle loads are four-axis,five-axis,and six-axis.This shows that when studying the change of slope safety factor under the dual influence of vehicle loads and rainfall,rainfall is the main cause of slope stability;The change rate of slope safety factor increases gradually with the increase of rainfall,and the change trends of the upper,lower and overall parts of the slope are similar. 展开更多
关键词 LOESS coupling action Slope stability Iso-water content layer
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Simulation and Traffic Safety Assessment of Heavy-Haul Railway Train-Bridge Coupling System under Earthquake Action 被引量:1
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作者 Liangwei Jiang Wei Zhang +3 位作者 Hongyin Yang Xiucheng Zhang Jinghan Wu Zhangjun Liu 《Structural Durability & Health Monitoring》 EI 2024年第6期835-851,共17页
Aiming at the problem that it is difficult to obtain the explicit expression of the structural matrix in the traditional train-bridge coupling vibration analysis,a combined simulation system of train-bridge coupling s... Aiming at the problem that it is difficult to obtain the explicit expression of the structural matrix in the traditional train-bridge coupling vibration analysis,a combined simulation system of train-bridge coupling system(TBCS)under earthquake(MAETB)is developed based on the cooperative work of MATLAB and ANSYS.The simulation system is used to analyze the dynamic parameters of the TBCS of a prestressed concrete continuous rigid frame bridge benchmark model of a heavy-haul railway.The influence of different driving speeds,seismic wave intensities,and traveling wave effects on the dynamic response of the TBCS under the actions of the earthquakes is discussed.The results show that the bridge displacement increase in magnitude in the lateral direction is more significant than in the vertical direction under the action of an earthquake.The traveling wave effect can significantly reduce the lateral response of the bridge,but it will significantly increase the train derailment coefficient.When the earthquake intensity exceeds 0.2 g,the partial derailment coefficient of the train has exceeded the limit value of the specification. 展开更多
关键词 Train-bridge coupling vibration analysis dynamic response earthquake action traveling wave effect
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Fluid Resonance in a Moonpool Coupling with Heave Motion Response of Hulls with Sharp and Convex Edge Profiles
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作者 TANG Peng LAN Jun-jie +2 位作者 HUANG Yong-qiang JIANG Sheng-chao ZHANG Hong-sheng 《China Ocean Engineering》 2025年第2期225-231,共7页
Numerical simulations on the coupling actions between the free surface oscillation in the moonpool and the heave motion response of hulls with vertical mooring stiffness are carried out in this study,where the influen... Numerical simulations on the coupling actions between the free surface oscillation in the moonpool and the heave motion response of hulls with vertical mooring stiffness are carried out in this study,where the influences of edge profiles,including sharp and convex edge profiles,on the coupling actions are considered.Two-peak variations in the free surface oscillations in the moonpool with incident wave frequencies can be observed,which are defined as the first and second peak frequencies.The free surface oscillations and heave motion responses show in-phase and out-of-phase relationships at the first and second peak frequencies,respectively.The convex edge profiles are able to generate effective suppressing actions at the second peak frequencies.However,it is only efficient for large vertical stiffness at the first peak frequency.The relative velocity between the fluid flow along the moonpool bottom and the heave motion of the hulls is the essential reason. 展开更多
关键词 fluid resonance moonpool heave motion response edge profiles coupling actions OPENFOAM
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Strength Optimization and Prediction of Cemented Tailings Backfill Under Multi-Factor Coupling
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作者 HU Yafei LI Keqing +1 位作者 HAN Bin JI Kun 《Journal of Shanghai Jiaotong university(Science)》 EI 2024年第5期845-856,共12页
In order to solve the problem of strength instability of cemented tailings backfill(CTB)under low temperature environment(≤20℃),the strength optimization and prediction of CTB under the influence of multiple factors... In order to solve the problem of strength instability of cemented tailings backfill(CTB)under low temperature environment(≤20℃),the strength optimization and prediction of CTB under the influence of multiple factors were carried out.The response surface method(RSM)was used to design the experiment to analyze the development law of backfill strength under the coupling effect of curing temperature,sand-cement ratio and slurry mass fraction,and to optimize the mix proportion;the artificial neural network algorithm(ANN)and particle swarm optimization algorithm(PSO)were used to build the prediction model of backfill strength.According to the experimental results of RSM,the optimal mix proportion under different curing temperatures was obtained.When the curing temperature is 10-15℃,the best mix proportion of sand-cement ratio is 9,and the slurry mass fraction is 71%;when the curing temperature is 15-20℃,the best mix proportion of sand-cement ratio is 8,and the slurry mass fraction is 69%.The ANN-PSO intelligent model can accurately predict the strength of CTB,its mean relative estimation error value and correlation coefficient value are only 1.95%and 0.992,and the strength of CTB under different mix proportion can be predicted quickly and accurately by using this model. 展开更多
关键词 cemented tailings backfill(CTB) response surface method(RSM) multi-factor coupling strength optimization intelligent prediction model
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A universal thermodynamic model of calculating mass action concentrations for structural units or ion couples in aqueous solutions and its applications in binary and ternary aqueous solutions 被引量:1
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作者 杨学民 赵伟洁 +2 位作者 柴国明 郭汉杰 张强 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2011年第3期626-641,共16页
A universal thermodynamic model of calculating mass action concentrations for structural units or ion couples in ternary and binary strong electrolyte aqueous solution was developed based on the ion and molecule coexi... A universal thermodynamic model of calculating mass action concentrations for structural units or ion couples in ternary and binary strong electrolyte aqueous solution was developed based on the ion and molecule coexistence theory and verified in four kinds of binary aqueous solutions and two kinds of ternary aqueous solutions. The calculated mass action concentrations of structural units or ion couples in four binary aqueous solutions and two ternary solutions at 298.15 K have good agreement with the reported activity data from literatures after shifting the standard state and concentration unit. Therefore, the calculated mass action concentrations of structural units or ion couples from the developed universal thermodynamic model for ternary and binary aqueous solutions can be applied to predict reaction ability of components in ternary and binary strong electrolyte aqueous solutions. It is also proved that the assumptions applied in the developed thermodynamic model are correct and reasonable, i.e., strong electrolyte aqueous solution is composed of cations and anions as simple ions, H2O as simple molecule and other hydrous salt compounds as complex molecules. The calculated mass action concentrations of structural units or ion couples in ternary and binary strong electrolyte aqueous solutions strictly follow the mass action law. 展开更多
关键词 universal thermodynamic model mass action concentration activity ternary aqueous solution binary aqueous solution ion and molecule coexistence theory structural units ion couples components
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Numerical simulation and experimental validation of moisture-heat coupling for saturated frozen soils 被引量:3
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作者 Zhi Ming Li Jian Chen +1 位作者 Kai Sun Bin Zhang 《Research in Cold and Arid Regions》 CSCD 2017年第3期250-257,共8页
In seasonally frozen regions,freezing-and-thawing action is the main cause responsible for the destruction of canals,which is closely linked to the temperature gradient and water transport.To investigate the behaviour... In seasonally frozen regions,freezing-and-thawing action is the main cause responsible for the destruction of canals,which is closely linked to the temperature gradient and water transport.To investigate the behaviour of soils under freezing-and-thawing actions,many numerical models have been established that consider the important coupling of moisture transport and temperature evolution;but they contain excessive parameters,some of which are rather difficult to determine.Based on the well-known Harlan's theory,a simple moisture-heat coupling model was recently proposed to quantify the coupled moisture-heat transport performance of soils in terms of the central temperature and porosity.The mathematical module of COMSOL Multiphysics was further employed to solve the governing equations numerically.To validate our model,a thorough experimental scheme was carried out in our lab.The measured temperature distribution was found to be consistent with the predicted results. 展开更多
关键词 saturated FROZEN soil moisture-heat coupling freezing-and-thawing action CANAL
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Calculating models of mass action concentrations for structural units or ion couples in RbCl-H_2O binary system and RbCl-RbNO_3-H_2O ternary system 被引量:1
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作者 郭汉杰 杨学民 赵伟洁 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2010年第6期1112-1120,共9页
Thermodynamic models of calculating mass action concentrations for structural units or ion couples in RbCl-H2O binary and RbCl-RbNO3-H2O ternary strong electrolyte aqueous solutions were developed based on the ion and... Thermodynamic models of calculating mass action concentrations for structural units or ion couples in RbCl-H2O binary and RbCl-RbNO3-H2O ternary strong electrolyte aqueous solutions were developed based on the ion and molecule coexistence theory at 298.15 K.A transformation coefficient is needed to compare the calculated mass action concentration and the reported activity because they are obtained at different standard states and concentration units.The results show that the transformation coefficients between the calculated mass action concentrations and the reported activities of the same structural units or ion couples in RbCl-H2O binary and RbCl-RbNO3-H2O ternary strong electrolyte aqueous solutions change in a very narrow range.The transformed mass action concentrations of structural units or ion couples in RbCl-H2O binary system are in good agreement with the reported activities. The transformed mass action concentrations of RbCl and RbNO3 in RbCl-RbNO3-H2O ternary solution are also in good agreement with the reported activities,aRbCl and 3RbNOa,with different total ionic strengths as 0.01,0.05,0.1,0.5,1.0,1.5,2.0,3.0 and 3.5 mol/kg,respectively.All those results mean the developed thermodynamic model of strong electrolyte aqueous solutions can reflect structural characteristics of RbCl-H2O binary and RbCl-RbNO3-H2O ternary strong electrolyte aqueous solutions and the mass action concentration also strictly follows the mass action law. 展开更多
关键词 mass action concentration ACTIVITY ion and molecule coexistence theory RbCl-H2O RbCl-RbNO3-H2O structural unit ion couple
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基于ActionScript3语言的组件库架构研究
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作者 薛冲 薛阳 《煤矿机械》 2017年第2期166-168,共3页
根据松耦合的原则,通过软件工程中样式展现与逻辑处理相分离,构建一套完整的组件库,该组件库可以使程序开发人员与美术人员的工作不再相互依赖,让频繁的需求变更不再过多的影响到项目开发的进度,有效提高前端Flash界面组件的开发效率和... 根据松耦合的原则,通过软件工程中样式展现与逻辑处理相分离,构建一套完整的组件库,该组件库可以使程序开发人员与美术人员的工作不再相互依赖,让频繁的需求变更不再过多的影响到项目开发的进度,有效提高前端Flash界面组件的开发效率和团队的工作效率。组件的具体皮肤样式可以完全通过美术所提供的素材决定,因此组件皮肤样式可以实现完全自定义。通过直接加载素材、位图渲染的形式,提高程序的执行效率。同时,组件库的设计初衷就是尽量避免过于依赖某一个具体语言的某种特性,借助软件工程中松耦合的通用性,可以较为轻松地实现使用其他计算机语言。 展开更多
关键词 actionsCRIPT3 松耦合 组件库 效率 性能 自定义 皮肤样式
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Transverse seismic response of beam aque-duct considering fluid-structure coupling
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作者 季日臣 夏修身 +1 位作者 陈尧隆 王丽 《Acta Seismologica Sinica(English Edition)》 CSCD 2007年第3期348-355,共8页
Based on the theory of Housner, the transverse seismic response of beam aqueduct considering fluid-structure coupling is established. With the variation of aqueduct cross-section ratio of depth to width, the aqueduct ... Based on the theory of Housner, the transverse seismic response of beam aqueduct considering fluid-structure coupling is established. With the variation of aqueduct cross-section ratio of depth to width, the aqueduct transverse seismic response change. The transverse seismic response of a large-scale aqueduct in several work condition are calculated. It shows that the transverse seismic response is greatly influenced by the water mass in the aqueduct, but the shaking water play a TLD role. ff the whole water is appended aqueduct body, it will magnify seismic inertia action. When aqueduct cross-section is selected, the influence of ratio of depth and width to pier seismic response should be considered in order to reduce seismic action. 展开更多
关键词 AQUEDUCT fluid-structure coupling seismic response water model TLD action
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A Study of Compound Action Potentials in Current-Coupled Tracts: the General Case
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作者 Aman Chawla Salvatore Domenic Morgera 《Journal of Applied Mathematics and Physics》 2023年第11期3345-3353,共9页
In this paper, the authors investigate compound action potentials formed when the underlying tract's axons have current-mediated coupling amongst themselves, and no field-mediated coupling. The key finding of the ... In this paper, the authors investigate compound action potentials formed when the underlying tract's axons have current-mediated coupling amongst themselves, and no field-mediated coupling. The key finding of the paper is that, for the case of biophysically inhomogeneous axon tracts, the compound action potential is governed by a Hodgkin-Huxley like equation itself in certain cases. The paper extends an earlier result for the identical axon case. 展开更多
关键词 Compound action Potentials Current-Mediated coupling Biophysically Inhomogeneous Axon Tracts Hodgkin-Huxley Equation Identical Axon Case
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Static and Dynamic Analysis of Lasing Action from Single and Coupled Photonic Crystal Nanocavity Lasers
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作者 Peng-Chao Zhao Fan Qi +2 位作者 Ai-Yi Qi Yu-Fei Wang Wan-Hua Zheng 《Chinese Physics Letters》 SCIE CAS CSCD 2017年第2期30-33,共4页
The single and coupled photonic crystal nanocavity lasers are fabricated in the InGaAsP material system and their static and dynamic features are compared. The coupled-cavity lasers show a larger lasing e^ciency and g... The single and coupled photonic crystal nanocavity lasers are fabricated in the InGaAsP material system and their static and dynamic features are compared. The coupled-cavity lasers show a larger lasing e^ciency and generate an output power higher than the single-cavity lasers, results that are consistent with the theoretical results obtained by rate equations. In dynamic regime, the single-cavity lasers produce pulses as short as 113 ps, while the coupled-cavity lasers show a significantly longer lasing duration. These results indicate that the photonic crystal laser is a promising candidate for the light source in high-speed photonic integrated circuit. 展开更多
关键词 Static and Dynamic Analysis of Lasing action from Single and coupled Photonic Crystal Nanocavity Lasers
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人-结构相互作用对人行桥振动响应的影响分析 被引量:1
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作者 唐冕 张金龙 +1 位作者 宋旭明 周雨洁 《铁道科学与工程学报》 北大核心 2025年第1期207-220,共14页
在人行桥中合理地考虑人-结构相互作用(human-structure-interaction,HSI)、真实预测出人群引起的振动响应,建立基于国人身体特性并考虑交通流的行人荷载模拟方式及合理的单自由度弹簧-质量-阻尼人体模型(spring-mass-damping,SMD),利... 在人行桥中合理地考虑人-结构相互作用(human-structure-interaction,HSI)、真实预测出人群引起的振动响应,建立基于国人身体特性并考虑交通流的行人荷载模拟方式及合理的单自由度弹簧-质量-阻尼人体模型(spring-mass-damping,SMD),利用随机概率分布的傅里叶级数,采用具有时空变化的移动步行荷载与人体动力学模式相结合的方式模拟人-结构相互作用。通过有限元软件建立SILVA实验中的人-桥一体化的三维空间有限元模型,对比分析验证行人模拟方式的合理性,进一步探究人群动力效应模拟和行人整体效应对人行桥动力特性及响应的影响。研究结果表明:单人因素作用下,当人行桥处于非共振时,移动力(MF)模型和弹簧-质量-阻尼器(SMD)模型的差异率仅为0.8%,人行桥处于临近共振时两模型的差异率达到15%,MF模型和SMD模型模拟结果差异显著,有必要考虑人体模型的影响;人群荷载作用下,高阶谐波的响应显著增加,最小增幅约为83.2%,相位角按照[0,2π]均匀分布取值更接近实际荷载状态,人体效应模拟比纯荷载模拟更接近SILVA实验的实测结果,考虑HSI效应可以较好体现行人在振动表面行走的净效应;行人纵向分布和路径的方向性对横向振动的影响显著,对竖向振动的影响可忽略;结构振动响应与人群同步率之间存在强烈的正相关性。研究结果可为考虑人-桥相互作用的耦合动力分析提供一定的参考。 展开更多
关键词 人行桥 振动 人体动力学 随机人群 耦合作用
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风浪联合作用下驳船型海上浮式风机的非线性耦合模型与TMD振动控制研究 被引量:2
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作者 孔凡 陈玲霜 +2 位作者 郑达成 李书进 董华 《振动工程学报》 北大核心 2025年第1期8-18,共11页
海上浮式风机是捕获深远海风能的重要装置,是风能开发的主要研究方向之一。驳船型风机多采用二维低阶简化动力学模型和非线性最小二乘参数识别方法,建立高阶耦合动力模型能更准确地反映其动力特性。本文关注驳船型海上浮式风机的多体系... 海上浮式风机是捕获深远海风能的重要装置,是风能开发的主要研究方向之一。驳船型风机多采用二维低阶简化动力学模型和非线性最小二乘参数识别方法,建立高阶耦合动力模型能更准确地反映其动力特性。本文关注驳船型海上浮式风机的多体系统,建立风浪联合作用下的16自由度耦合动力学模型,通过数值仿真验证模型的准确性。其中,利用修正的叶素动量理论计算叶片气动荷载,利用线性势流理论计算波浪荷载,采用准静态法计算系泊张力。此外,为减小驳船型海上浮式风机的结构振动,在考虑发电机转矩控制和叶片集体变桨控制的基础上,提出将双向碰撞调谐质量阻尼器置于机舱中,并引入限位装置控制振子行程。随后,通过穷举法和遗传算法进行控制参数优化。仿真分析表明,本文所建模型可准确计算驳船型海上浮式风机的动力响应;双向碰撞调谐质量阻尼器对结构振动有较好的控制效果。 展开更多
关键词 振动控制 驳船型海上浮式风机 非线性耦合模型 双向TMD 风浪联合作用
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基于改进近端策略优化算法的柔性作业车间调度 被引量:2
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作者 王艳红 付威通 +2 位作者 张俊 谭园园 田中大 《控制与决策》 北大核心 2025年第6期1883-1891,共9页
柔性作业车间调度是经典且复杂的组合优化问题,对于离散制造系统的生产优化具有重要的理论和实际意义.基于多指针图网络框架和近端策略优化算法设计一种求解柔性作业车间调度问题的深度强化学习算法.首先,将“工序-机器”分配调度过程... 柔性作业车间调度是经典且复杂的组合优化问题,对于离散制造系统的生产优化具有重要的理论和实际意义.基于多指针图网络框架和近端策略优化算法设计一种求解柔性作业车间调度问题的深度强化学习算法.首先,将“工序-机器”分配调度过程表征成由选择工序和分配机器两类动作构成的马尔可夫决策过程;其次,通过解耦策略解除动作之间的耦合关系,并设计新的损失函数和贪婪采样策略以提高算法的验证推理能力;在此基础上扩充状态空间,使评估网络能够更全面地感知与评估,从而进一步提升算法的学习和决策能力.在随机生成算例及基准算例上进行仿真和对比分析,验证算法的良好性能及泛化能力. 展开更多
关键词 柔性作业车间调度 近端策略优化算法 双动作耦合网络 损失函数优化 贪婪采样 深度强化学习
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地震与风作用下钢框架-自复位支撑筒结构损伤分析 被引量:1
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作者 徐龙河 刘媛媛 谢行思 《振动工程学报》 北大核心 2025年第1期126-134,共9页
为揭示地震‐风同时作用和先后作用下自复位支撑结构的损伤分布规律,对一50层钢框架‐自复位支撑筒在不同强度地震动与50年重现期风荷载下的梁/柱构件和结构整体损伤进行分析。结果表明,地震单独作用和地震‐风同时作用下,支撑筒梁均比... 为揭示地震‐风同时作用和先后作用下自复位支撑结构的损伤分布规律,对一50层钢框架‐自复位支撑筒在不同强度地震动与50年重现期风荷载下的梁/柱构件和结构整体损伤进行分析。结果表明,地震单独作用和地震‐风同时作用下,支撑筒梁均比外框架梁先受损,支撑筒柱较外框架柱损伤发展更快;地震‐风同时作用增大了柱的损伤程度,使31层柱的最大损伤值增大了78.6%;随着地震动强度的增大,风荷载作用对结构整体损伤的加重程度逐渐增大。在不同强度的地震动与50年重现期风荷载先后作用下,风荷载增大了震损结构的最大残余变形角均值;当峰值地面加速度为10 m/s^(2)时,风荷载使震损结构的最大残余变形角均值由0.325%增至0.330%,但风荷载对震损结构损伤最大构件的损伤状态影响不大。 展开更多
关键词 损伤识别 地震‐风耦合作用 自复位支撑 高层钢结构 残余变形
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地震波浪联合作用下高速列车深水斜拉桥系统空间耦合振动分析
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作者 郭文华 薛超 +1 位作者 段彬鑫 赵大亮 《中南大学学报(自然科学版)》 北大核心 2025年第4期1454-1465,共12页
提出同时考虑地震和波浪联合作用下高速列车-深水斜拉桥时变系统空间耦合振动分析方法。首先,建立考虑轨道不平顺影响的列车-轨道-斜拉桥系统动力分析模型,桥梁水下结构地震动水压力基于水体辐射理论通过刚性柱法将其转换为附加质量,采... 提出同时考虑地震和波浪联合作用下高速列车-深水斜拉桥时变系统空间耦合振动分析方法。首先,建立考虑轨道不平顺影响的列车-轨道-斜拉桥系统动力分析模型,桥梁水下结构地震动水压力基于水体辐射理论通过刚性柱法将其转换为附加质量,采用莫里森方程与绕射波浪理论模拟桥梁水下结构波浪力,建立地震和波浪联合作用下高速列车-深水斜拉桥时变系统空间振动方程。基于ANSYS与SIMPACK联合仿真分析平台,分别研究仅地震作用、仅波浪作用以及地震与波浪联合作用下高速列车-深水斜拉桥系统空间振动,研究单独地震动水压力、单独波浪力作用和两者联合作用对车桥系统动力响应的影响。计算结果表明:考虑地震动水压力时,列车轮重减载率、脱轨系数、轮轴横向力、横向加速度等显著增大,且当地震强度超过0.10g时,地震动水压力作用对车桥响应影响更加显著;仅波浪作用对耦合系统动力响应影响较小;地震与波浪的相位差对耦合系统动力响应影响显著;随着相位差改变,考虑波浪力与不考虑波浪力时相比,耦合系统动力响应增长幅度最大的参数为脱轨系数,增长幅度最大为11.0%。 展开更多
关键词 车桥耦合 深水斜拉桥 地震动水力 波浪作用 相位差
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粤港澳大湾区土地绿色利用推动构建新质生产力研究
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作者 彭文英 陈泽宇 +1 位作者 赵爽 单子溢 《经济地理》 北大核心 2025年第9期190-199,共10页
文章在解析土地绿色利用对新质生产力的推动作用机理基础上,基于2012—2022年粤港澳大湾区地级及以上行政单元数据,运用SBM-DEA模型、熵权法、耦合协调模型、双向固定效应模型及Tobit模型方法,对大湾区土地绿色利用和新质生产力水平的... 文章在解析土地绿色利用对新质生产力的推动作用机理基础上,基于2012—2022年粤港澳大湾区地级及以上行政单元数据,运用SBM-DEA模型、熵权法、耦合协调模型、双向固定效应模型及Tobit模型方法,对大湾区土地绿色利用和新质生产力水平的时空格局及二者的时空交互关系进行了测度分析。结果表明:①研究期内大湾区土地绿色利用、新质生产力水平整体上呈上升趋势,时空层面分别表现出非均衡交错分布及低水平均衡向高水平不均衡演进的格局特征;②土地绿色利用与新质生产力的耦合协调水平呈阶段性波动上升趋势,经济发展、实际利用外资、科技和资源承载水平对耦合协调水平具有明显的正向驱动,收入、教育和生态环境水平表现出时间滞后的正向驱动作用;③土地绿色利用显著推动新质生产力发展,其中地均第三产业产值和人口密度对新质生产力正向影响显著。针对大湾区具体情形,提出了以土地绿色利用推动构建新质生产力的核心战略与优势驱动、因地制宜与协同合作的发展策略。 展开更多
关键词 新质生产力 土地绿色利用 时空格局 作用机理 耦合协调度 粤港澳大湾区
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