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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-carry.ng 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

Partial linear Model Averaging Prediction for Longitudinal Data

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Journal of Systems Science & Complexity 2024年第2期37卷 863-885页

作者： li na fei yu ZHAnG Xinyu Faculty of Science Kunming University of Science and TechnologyKunming 650500China School of Statistics and Mathematics Yunnan University of Finance and EconomicsKunming 650221China Academy of Mathematics and Systems Science Chinese Academy of SciencesBeijing 100190China

Prediction plays an important role in data *** averaging method generally provides better prediction than using any of its *** though model averaging has been extensively investigated under independent errors,few authors have considered model averaging for semiparametric models with correlated *** this paper,the authors offer an optimal model averaging method to improve the prediction in partially linear model for longitudinal *** model averaging weights are obtained by minimizing criterion,which is an unbiased estimator of the expected in-sample squared error loss plus a *** properties,including asymptotic optimality and consistency of averaging weights,are established under two scenarios:(i)All candidate models are misspecified;(ii)Correct models are available in the candidate *** studies and an empirical example show that the promise of the proposed procedure over other competitive methods.

关键词： Asymptotic optimality longitudinal data model averaging estimator partially linear model prediction

Considering solid shear stress in MP-PIC simulation of a CFB riser

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Particuology 2024年第6期89卷 79-87页

作者： Tagir Kadyrov fei li Atta Ullah nature-inspired Engineering Center University of TyumenTyumen 625003Russia Laboratory of Theory and Optimization of Chemical and Technological Processes University of TyumenTyumen625003Russia State Key Laboratory of Multi-phase Complex Systems Institute of Process EngineeringChinese Academy of SciencesBeijing 100190China Department of Chemical Engineering Pakistan Institute of Engineering&Applied SciencesIslamabad 45650Pakistan

To enable successful multi-phase particle-in-cell(MP-PIC)simulations of circulating fluidized beds(CFBs),both the interphase drag force and interparticle collisions need to be carefully *** collisions are usually represented by the solid stress consisting of the normal and shear components,in which the normal stress was found to have a leading role in the numerical stability of MP-PIC simulations,whereas the impact of the shear stress has seldom been *** this work,the effects of the solid shear stress are investigated by using two-dimensional simulations of the moderately dense laboratory-scale CFB riser with in-house MP-PIC code implemented on MFIX open-source *** including only.normal solid stress and those considering both normal and shear solid stresses are *** results of solids flux,axial and radial solids profiles are compared with available experimental *** results show that the solid shear stress plays a minor role on the accuracy of simulation,and the increase of PPP(number particles per parcel)leads to a lower accuracy of simulation.

关键词： Simulation Fluidization Multiphase particle-in-cell(MP-PIC) Solid shear stress

Recent progress in side chain engineering of y-series non-fullerene molecule and polymer acceptors

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Science China Chemistry 2024年第3期67卷 788-805页

作者： li Tian Chunchen liu fei Huang School of Materials Science and Engineering Henan University of TechnologyZhengzhou 450001China Institute of Polymer Optoelectronic Materials and Devices State Key Laboratory of Luminescent Materials and DevicesSouth China University of TechnologyGuangzhou 510640China

Organic solar cells(OSCs) have drawn considerable attention in the last decade due to the great potential of light weight,flexibility, and low-cost solution processing. Particularly, y-series non-fullerene acceptors(nFAs) including small molecular acceptors(SMAs) and polymerized small molecular acceptors(PSMAs) have become research hot spots due to their excellent power conversion efficiency. Side chain engineering is crucial to adjust the solubility and crystallinity of nFAs, which will significantly affect the morphology of active layers and the efficiency of OSCs. However, the understanding of side chain engineering on nFAs is still limited and lacks a systematic review. This review aims to provide a brief summary of the recent developments in side chain engineering of nFAs, with a special focus on the design and application of y-series SMAs and PSMAs for high-efficiency.non-fullerene organic solar cells(nF-OSCs). In addition, the review also points out challenges and provides useful guidance regarding side chain regulation for y-series nFAs.

关键词： organic solar cell y-series non-fullerene acceptors side chain engineering

Impacts of pancreatic exocrine insufficiency on gut microbiota

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2024年第4期25卷 271-279页

作者： yulin GUO Feng CAO fei li Department of General Surgery Xuanwu Hospital of Capital Medical UniversityBeijing 100053China Acute Pancreatitis Clinical Center of Capital Medical University Beijing 100053China

Pancreatic exocrine insufficiency(PEI)can be induced by various kinds of diseases,including chronic pancreatitis,acute pancreatitis,and *** main pathogenetic mechanism of PEI involves the decline of trypsin synthesis,disorder of pancreatic fluid flow,and imbalance of secretion *** studies have shown that PEI could induce gut bacterial overgrowth and dysbiosis,with the abundance of Lactobacillus and Bifidobacterium increasing the most,which could be partially reversed by pancreatic enzyme replacement *** studies have also confirmed the association between PEI and the dysbiosis of gut *** exocrine secretions and changes in duodenal p H as well as bile salt malabsorption brought about by PEI may affect and shape the abundance and composition of gut *** turn,the gut microbiota may impact the pancreatic exocrine acinus through potential bidirectional *** forward,more and higher-quality studies are needed that focus on the mechanism underly.ng the impact of PEI on the gut microbiota.

关键词： Pancreatic exocrine insufficiency Gut microbiota Gut microbiome Pancreatic enzyme replacement therapy

SAC-Based Computation Offloading for Reconfigurable Intelligent Surface-Aided Mobile Edge networks

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China Communications 2024年第6期21卷 261-270页

作者： li Bin Qian Zhen fei Zesong School of Computer Science Nanjing University of Information Science&TechnologyNanjing 210044China Jiangsu Collaborative Innovation Center of Atmospheric Environment and Equipment Technology(CICAEET) Nanjing University of Information Science&TechnologyNanjing 210044 School of Information and Electronics Beijing Institute of TechnologyBeijing 100081China

In this paper,we concentrate on a reconfigurable intelligent surface(RIS)-aided mobile edge computing(MEC)system to improve the offload efficiency with moving user equipments(UEs).We aim to minimize the energy consumption of all UEs by jointly optimizing the discrete phase shift of RIS,UEs’transmitting power,computing resources allocation,and the UEs’task offloading strategies for local computing and *** formulated problem is a sequential decision making across multiple coherent time ***,the mobility of UEs brings uncertainties into the decision-making *** cope with this challenging problem,the deep reinforcement learning-based Soft Actor-Critic(SAC)algorithm is first proposed to effectively optimize the discrete phase of RIS and the UEs’task offloading ***,the transmitting power and computing resource allocation can be determined based on the *** results demonstrate that the proposed algorithm can be trained more stably and perform approximately 14%lower than the deep deterministic policy gradient benchmark in terms of energy consumption.

关键词： MEC RIS soft actor-critic user mobility

Attention Markets of Blockchain-Based Decentralized Autonomous Organizations

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IEEE/CAA Journal of Automatica Sinica 2024年第6期11卷 1370-1380页

作者： Juanjuan li Rui Qin Sangtian Guan Wenwen Ding fei lin fei-yue Wang State Key Laboratory of Multimodal Artificial Intelligence Systems Institute of AutomationChinese Academy of SciencesBeijing 100190China Faculty of Innovation Engineering Macao University of Science and TechnologyMacao 999078China State Key Laboratory for Management and Control of Complex Systems Chinese Academy of SciencesBeijing 100190 Faculty of Innovation Engineering Macao University of Science and TechnologyMacao 999078China IEEE

The attention is a scarce resource in decentralized autonomous organizations(DAOs),as their self-governance relies heavily on the attention-intensive decision-making process of“proposal and voting”.To prevent the negative effects of pro-posers’attention-capturing strategies that contribute to the“tragedy of the commons”and ensure an efficient distribution of attention among multiple proposals,it is necessary to establish a market-driven allocation scheme for DAOs’***,the Harberger tax-based attention markets are designed to facilitate its allocation via continuous and automated trading,where the individualized Harberger tax rate(HTR)determined by the pro-posers’reputation is ***,the Stackelberg game model is formulated in these markets,casting attention to owners in the role of leaders and other competitive proposers as *** equilibrium trading strategies are also discussed to unravel the intricate dynamics of attention ***,utilizing the single-round Stackelberg game as an illustrative example,the existence of nash equilibrium trading strategies is ***,the impact of individualized HTR on trading strategies is investigated,and results suggest that it has a negative correlation with leaders’self-accessed prices and ownership duration,but its effect on their revenues varies under different *** study is expected to provide valuable insights into leveraging attention resources to improve DAOs’governance and decision-making process.

关键词： Attention decentralized autonomous organizations Harberger tax Stackelberg game.

Bayesian Filtering for High-Dimensional State-Space Models With State Partition and Error Compensation

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IEEE/CAA Journal of Automatica Sinica 2024年第5期11卷 1239-1249页

作者： Ke li Shunyi Zhao Biao Huang fei liu Key Laboratory of Advanced Process Control for light Industry(Ministry of Education) Institute of AutomationJiangnan UniversityWuxi 214122China Department of Chemical and Materials Engineering University of AlbertaEdmonton AB T6G 2G6Canada

In the era of exponential growth of data availability,the architecture of systems has a trend toward high dimensionality,and directly exploiting holistic information for state inference is not always computationally *** paper proposes a novel Bayesian filtering algorithm that considers algorithmic computational cost and estimation accuracy for high-dimensional linear *** high-dimensional state vector is divided into several blocks to save computation resources by avoiding the calculation of error covariance with immense *** that,two sequential states are estimated simultaneously by introducing an auxiliary variable in the new probability space,mitigating the performance degradation caused by state ***,the computational cost and error covariance of the proposed algorithm are analyzed analytically to show its distinct features compared with several existing *** results illustrate that the proposed Bayesian filtering can maintain a higher estimation accuracy with reasonable computational cost when applied to high-dimensional linear systems.

关键词： filtering estimation error

The Monsky Matrices and non-congruent numbers

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Algebra Colloquium 2024年第2期31卷 239-262页

作者： Guilin li Hourong Qin fei Xu Department of Mathematics Nanjing UniversityNanjing 210093China 不详

We give some sufficient conditions for non-congruent numbers in terms of the Monsky *** known criteria for non-congruent numbers can be viewed as special cases of our results.

关键词： congruent elliptic curve Selmer group Monsky matrix non-congruent number