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Probabilistic-Ellipsoid Hybrid Reliability Multi-Material Topology Optimization Method Based on Stress Constraint

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Computer Modeling in Engineering & Sciences 2024年第7期140卷 757-792页

作者： Zibin Mao Qinghai Zhao liang zhang College of Mechanical and Electrical Engineering Qingdao UniversityQingdao266071China National Engineering Research Center for Intelligent Electrical Vehicle Power System Qingdao UniversityQingdao266071China

This paper proposes a multi-material topology optimization method based on the hybrid reliability of the probability-ellipsoid model with stress constraint for the stochastic uncertainty and epistemic uncertainty of mechanical loads in optimization *** probabilistic model is combined with the ellipsoidal model to describe the uncertainty of mechanical *** topology optimization formula is combined with the ordered solid isotropic material with penalization(ordered-SIMP)multi-material interpolation *** stresses of all elements are integrated into a global stress measurement that approximates the maximum stress using the normalized p-norm ***,the sequential optimization and reliability assessment(SORA)is applied to transform the original uncertainty optimization problem into an equivalent deterministic topology optimization(DTO)*** response surface and sparse grid technique are combined with SORA to get accurate information on the most probable failure point(MPP).In each cycle,the equivalent topology optimization formula is updated according to the MPP information obtained in the previous *** adjoint variable method is used for deriving the sensitivity of the stress constraint and the moving asymptote method(MMA)is used to update design ***,the validity and feasibility of the method are verified by the numerical example of L-shape beam design,T-shape structure design,steering knuckle,and 3D T-shaped beam.

关键词： Stress constraint probabilistic-ellipsoid hybrid topology optimization reliability analysis multi-material design

Insights into the provenance implication of leaf wax n-alkanes along the lower Yellow River

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Science China Earth Sciences 2024年第6期67卷 2001-2018页

作者： liang zhang Jinzhao LIU Chong JIANG Fei zhang Zhisheng AN School of Human Settlements and Civil Engineering Xi’an Jiaotong UniversityXi’an 710054China State Key Laboratory of Loess and Quaternary Geology Institute of Earth EnvironmentChinese Academy of SciencesXi’an 710061China National Observation and Research Station of Earth Critical Zone on the Loess Plateau of Shaanxi Xi’an 710061China

Serving as one of the largest rivers in terms of both sediment and organic carbon transport fluxes in the world,the Yellow River plays a crucial role in regional biogeochemical process as well as in the global carbon ***,although a large number of studies have been carried out on the flux,composition,source and seasonal variation of total particulate organic carbon in the Yellow River so far,studies on molecular biomarkers at different spatial and temporal scales are still *** this study,we focus on the molecular and hydrogen isotopic properties of leaf wax n-alkanes among different types of samples which obtained from different seasons(flood ***-flood)along the lower Yellow *** molecular distribution of n-alkanes show that the riparian topsoils are subject to inputs from the overlying vegetation,while the suspended sediments from the flood season are characterized by the mixing of soil materials which originate from various stratigraphy with different ages on the Chinese Loess *** to the contrasting hydrodynamic conditions,the n-alkanes in suspended sediments also show distinct molecular composition between flood and non-flood ***,considering the effect of climatic factors,the proportion of monocots in flood-season suspended sediments is calculated from a semi-quantitative perspective using δ^(2)H_(wax).Our findings may bring to light new considerations for the interpretation of leaf wax proxies in studies of organic matter sources of Yellow River.

关键词： Molecular distribution Hydrogen isotopic composition Leaf wax n-alkanes Suspended sediments Lower Yellow River

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Application of the finite analytic numerical method to a flowdependent variational data assimilation

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Acta Oceanologica Sinica 2024年第3期43卷 30-39页

作者： Yan Hu Wei Li Xuefeng zhang Guimei Liu liang zhang Tianjin Key Laboratory for Marine Environmental Research and Service School of Marine Science and TechnologyTianjin UniversityTianjin 300072China School of Marine Science and Technology Tianjin UniversityTianjin 300072China National Marine Environmental Forecasting Center Ministry of Natural ResourcesBeijing 100081China

An anisotropic diffusion filter can be used to model a flow-dependent background error covariance matrix,which can be achieved by solving the advection-diffusion *** of the directionality of the advection term,the discrete method needs to be chosen very *** finite analytic method is an alternative scheme to solve the advection-diffusion *** a combination of analytical and numerical methods,it not only has high calculation accuracy but also holds the characteristic of the auto *** demonstrate its ability,the one-dimensional steady and unsteady advection-diffusion equation numerical examples are respectively solved by the finite analytic *** more widely used upwind difference method is used as a control *** result indicates that the finite analytic method has higher accuracy than the upwind difference *** the two-dimensional case,the finite analytic method still has a better *** the three-dimensional variational assimilation experiment,the finite analytic method can effectively improve analysis field accuracy,and its effect is significantly better than the upwind difference and the central difference ***,it is still a more effective solution method in the strong flow region where the advective-diffusion filter performs most prominently.

关键词： finite analytic method advection-diffusion equation data assimilation flow-dependent

Gut flora in multiple sclerosis:implications for pathogenesis and treatment

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Neural Regeneration Research 2024年第7期19卷 1480-1488页

作者： Weiwei zhang Ying Wang Mingqin Zhu Kangding Liu Hong-liang zhang Department of Neurology the First Hospital of Jilin UniversityJilin UniversityChangchunJilin ProvinceChina Department of Life Sciences National Natural Science Foundation of ChinaBeijingChina

Multiple sclerosis is an inflammatory disorder chara cterized by inflammation,demyelination,and neurodegeneration in the central nervous *** current first-line therapies can help manage symptoms and slow down disease progression,there is no cure for multiple *** gut-brain axis refers to complex communications between the gut flo ra and the immune,nervous,and endocrine systems,which bridges the functions of the gut and the *** in the gut flora,termed dys biosis,can lead to systemic inflammation,leaky gut syndrome,and increased susceptibility to *** pathogenesis of multiple sclerosis involves a combination of genetic and environmental factors,and gut flora may play a pivotal role in regulating immune responses related to multiple scle *** develop more effective therapies for multiple scle rosis,we should further uncover the disease processes involved in multiple sclerosis and gain a better understanding of the gut-brain *** review provides an overview of the role of the gut flora in multiple scle rosis.

关键词： gut flora gut-brain axis multiple sclerosis pathogenesis treatment

Elastic buckling analysis and optimization of thin-walled bamboo-like pipe beam subjected to pure bending

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Chinese Journal of Aeronautics 2024年第3期37卷 133-152页

作者： Yayun YU Dongli MA liang zhang Xiaopeng YANG Hao GUAN School of Aeronautic Science and Engineering Beihang UniversityBeijing 100191China

In this paper,a stiffening design imitating the bamboo node is proposed for weight reduction of the long composite pipe beam subjected to bending *** distribution of bamboo nodes can efficiently suppress the ovalization of the section,thus significantly improving the bending resistance of the *** on this principle,ring stiffeners are proposed to be fixed to the pipe beam,making the long beam equivalent to the combination of a series of short pipes that suffered less section ovalization.A database of the optimal laminate orientations for different normalized lengths is obtained through optimizations,where the discreteness of the ply count is *** on this database,weight optimizations are conducted,and the optimal designs of beams with and without stiffeners are obtained and *** comparison results show that the proposed bamboo-like stiffened beam not only regains a near-linear load–displacement relationship,but also reduces the weight by up to 16%under the same buckling *** addition,it is found that for the pipe beams with radius-to-thickness ratios of more than 18,increasing the radius leads to a decrease in elastic buckling resistance when the weight remains a constant,which is opposite to the design for strength and *** model and database developed in this paper can provide a reference for weight reduction design and weight estimation for composite pipe beams.

关键词： Composite beam Buckling Thin-walled structure Unmanned aerial vehicles Bamboo

Regulation of Ti(C,N)deposition on hot surface of refractory in blast furnace hearth

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Journal of Iron and Steel Research International 2024年第6期31卷 1423-1435页

作者： Jian Cao Cui Wang Jjan-liang zhang Ke-xin Jiao Guo-hua zhang State Key Laboratory of Advanced Metallurgy University of Science and Technology BeijingBeijing 100083China School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083China

Ti(C,N)concentration was found to be lower on the hearth sidewall of a blast furnace and increased gradually toward the bottom of the blast *** Ti(C,N)protective layer in a blast furnace is ***,the formation of a Ti(C,N)protective layer was promoted by studying the heterogeneous nucleation principle of titanium compounds on different substances and regulation measures for the deposition process of titanium compounds on refractories or *** lattice disregistry between the titanium compounds and the main components in the refractory or the main impurities in the protective layer was calculated using a two-dimensional disregistry equation to study the heterogeneous nucleation principle of titanium *** results revealed that in refractory materials,the heterogeneous nucleation of carbonitride is weak when C,SiO_(2),and Al_(2)O_(3) are used as heterogeneous nucleation substrates,and the heterogeneous nucleation of carbonitride is strong when TiO_(2) and SiC are used as heterogeneous nucleation *** nucleation phases,TiC,TiN,Ti(C_(0.3),N_(0.7)),and Ti(C_(0.5),N_(0.5))have similar heterogeneous nucleation ability in single component refractory,and the type of carbonitride has little effect on the lattice *** impurities in the protective layer as the substrate phases are not conducive to the heterogeneous nucleation of *** CaS was used as the substrate phase,the heterogeneous nucleation ability of carbonitride was the *** carbon and alumina were not conducive to the heterogeneous nucleation of carbonitride,but carbon was more unfavourable than alumina.

关键词： Ti(C,N) Lattice disregistry Lattice constant Heterogeneous nucleation Regulation measure

Orientational growth behavior and mechanism of delta(δ)phase precipitation in cold-rolled Inconel 718 alloy during heat treatment

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Journal of Iron and Steel Research International 2024年第1期31卷 264-274页

作者： Neng-yong Ye Guang-liang zhang Tian-yue Huang Ming Cheng Shi-hong zhang Lei Wang School of Materials Science&Engineering Taizhou UniversityTaizhou318000ZhejiangChina Institute of Metal Research Chinese Academy of SciencesShenyang110016LiaoningChina

Due to the important role ofδphase's quantity and morphology in the mechanical and fatigue properties of Inconel 718 alloy and its components,it is necessary to renew insights into the effect of cold deformation on theδphase precipitation,especially on the morphology ***,the nucleation and growth behavior ofδphase in cold-rolled Inconel 718 alloy during aging were *** results show that the precipitation rate and volume fraction ofδphase increase with increasing the cold rolling reduction from 10%to 50%.The volume fraction ofδphase reaches equilibrium after 5 h,remaining at 5.98%,6.52%,and 6.79%under different rolling reductions(10%,30%,and 50%),*** nucleation ofδphase mainly occurs on different sites(grain boundaries,new twin boundaries and old twin boundaries)under 10%rolling reduction,whileδphase mainly nucleates on the new grain boundaries of static recrystallization due to 50%rolling *** the growth ofδphase undergoes a process of alternate orientation growth from spherical(nucleation)→short rod(longitudinal orientation growth)→short rod(radial orientation growth)→dynamic *** 10%rolling reduction,δphase tends to grow into the matrix,while under 50%rolling reduction,the orientation grows faster and is easily affected by the grain boundary curvature.

关键词： Inconel 718 alloy Cold rolling δphase Orientation growth Morphology evolution

New Insights into Microplastic Contamination in Different Types of Leachates: Abundances, Characteristics, and Potential Sources

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Engineering 2024年第6期37卷 62-68页

作者： Lei zhang Wentao Zhao liang zhang Zhenxiao Cai Ruiqi Yan Xia Yu DamiàBarceló Qian Sui State Environmental Protection Key Laboratory of Environmental Risk Assessment and Control on Chemical Process School of Resources and Environmental EngineeringEast China University of Science and TechnologyShanghai 200237China State Key Laboratory of Pollution Control and Resource Reuse College of Environmental Science and EngineeringTongji UniversityShanghai 200092China Shanghai Institute of Pollution Control and Ecological Security Shanghai 200092China PerkinElmer Inc.Shanghai 201203China Maihai Environmental Protection Technology Co. Ltd.SuzhouJiangsu 215000China Department of Environmental Chemistry Institute of Environmental Assessment and Water ResearchSpanish Council for Scientific Research(IDAEA-CSIC)Barcelona 08034Spain

Municipal solid waste(MSW)is an important destination for abandoned *** the waste disposal process,large plastic debris is broken down into microplastics(MPs)and released into the ***,current research only focuses on landfill leachates,and the occurrence of MPs in other leachates has not been ***,herein,the abundance and characteristics of MPs in three types of leachates,namely,landfill leachate,residual waste leachate,and household food waste leachate,were studied,all leachates were collected from the largest waste disposal center in *** results showed that the average MP abundances in the different types of leachates ranged from(129±54)to(1288±184)MP particles per liter(particlesL1)and the household food waste leachate exhibited the highest MP abundance(p80%)of small MPs(20–100 lm)in landfill leachates compared to other *** the best of our knowledge,this is the first study discussing the sources of MPs in different leachates,which is important for MP pollution control during MSW disposal.

关键词： Microplastics Landfill leachate Residual waste leachate Household food waste leachate Source

Brain-inspired multimodal approach for effluent quality prediction using wastewater surface images and water quality data

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Frontiers of Environmental Science & Engineering 2024年第3期18卷 69-82页

作者： Junchen Li Sijie Lin liang zhang Yuheng Liu Yongzhen Peng Qing Hu School of Environment Harbin Institute of TechnologyHarbin 150090China School of Environmental Science and Engineering Southern University of Science and TechnologyShenzhen 518055China Engineering Innovation Center of SUSTech(Beijing) Southern University of Science and TechnologyBeijing 100083China Faculty of Environment and Life Beijing University of TechnologyBeijing 100124China Engineering Research Center of Intelligence Perception and Autonomous Control Ministry of EducationBeijing 100124China

Efficiently predicting effluent quality through data-driven analysis presents a significant advancement for consistent wastewater treatment *** this study,we aimed to develop an integrated method for predicting effluent COD and NH3 *** employed a 200 L pilot-scale sequencing batch reactor(SBR)to gather multimodal data from urban sewage over 40 *** we collected data on critical parameters like COD,DO,pH,NH_(3),EC,ORP,SS,and water temperature,alongside wastewater surface images,resulting in a data set of approximately 40246 *** we proposed a brain-inspired image and temporal fusion model integrated with a CNN-LSTM network(BITF-CL)using this *** innovative model synergized sewage imagery with water quality data,enhancing prediction *** a result,the BITF-CL model reduced prediction error by over 23%compared to traditional methods and still performed comparably to conventional techniques even without using DO and SS sensor ***,this research presents a cost-effective and precise prediction system for sewage treatment,demonstrating the potential of brain-inspired models.

关键词： Wastewater treatment system Water quality prediction Data driven analysis Brain-inspired model Multimodal data Attention mechanism