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Fast and Accurate Predictor-Corrector Methods Us.ng Feedback-Accelerated Picard Iteration for strongly nonlinear Problems

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Computer Modeling in Engineering & sciences 2024年第5期139卷 1263-1294页

作者： Xuechuan Wang wei He Haoyang Feng satya n.Atluri school of Astronautics Northwestern Polytechnical UniversityXi’an710072China Department of Mechanical Engineering Texas Tech UniversityLubbock79409USA

Although predictor-corrector methods have been extensively applied,they might not meet the requirements of practical applications and engineering tasks,particularly when high accuracy and efficiency are necessary.A novel class of correctors based on feedback-accelerated Picard iteration(FAPI)is proposed to further enhance computational *** optimal feedback terms that do not require inversion of matrices,significantly faster convergence speed and higher numerical accuracy are achieved by these correctors compared with their counterparts;however,the computational complexities are comparably *** advantages enable nonlinear engineering problems to be solved quickly and accurately,even with rough initial guesses from elementary *** proposed method offers flexibility,enabling the use of the generated correctors for either bulk process.ng of collocation nodes in a domain or successive corrections of a s.ngle node in a finite difference *** our method,the functional formulas of FAPI are discretized into numerical forms us.ng the collocation *** collocated iteration formulas can directly solve nonlinear problems,but they may require significant computational resources because of the manipulation of *** address this,the collocated iteration formulas are further converted into finite difference forms,enabling the design of lightweight predictor-corrector algorithms for real-time *** generality of the proposed method is illustrated by deriving new correctors for three commonly employed finite-difference approaches:the modified Euler approach,the Adams-Bashforth-Moulton approach,and the implicit Runge-Kutta ***,the updated approaches are tested in solving strongly nonlinear problems,including the Matthieu equation,the Duffing equation,and the low-earth-orbit tracking *** numerical findings confirm the computational accuracy and efficiency of the derived predictor-correc

关键词： Predictor-corrector method feedback-accelerated Picard iteration nonlinear dynamical system real-time computation

Dynamic and electrical responses of a curved s.ndwich beam with glass reinforced laminate layers and a pliable core in the pres.nce of a piezoelectric layer under low-velocity impact

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Applied Mathematics and Mechanics(English Edition) 2024年第1期45卷 155-178页

作者： n.sHAHVEIsI s.FELI Department of Mechanical Engineering Razi UniversityKermanshah ***Iran

The dynamic responses and generated voltage in a curved s.ndwich beam with glass reinforced laminate(GRL)layers and a pliable core in the pres.nce of a piezoelectric layer under low-velocity impact(LVI)are *** current study aims to carry out a dynamic analysis on the s.ndwich beam when the impactor hits the top face sheet with an initial *** the layer analysis,the high-order shear deformation theory(HsDT)and Frostig's second model for the displacement fields of the core layer are *** classical non-adhesive elastic contact theory and Hunter's principle are used to calculate the dynamic responses in terms of *** order to validate the analytical method,the outcomes of the current investigation are compared with those gained by the experimental tests carried out by other researchers for a rectangular composite plate subject to the *** element(FE)simulations are conducted by means of the ABAQUs *** effects of the parameters such as foam modulus,layer material,fiber angle,impactor mass,and its velocity on the generated voltage are reviewed.

关键词： analytical model piezoelectric layer curved s.ndwich beam glass reinforced laminate(GRL) pliable core low-velocity impact(LVI) classical non-adhesive elastic contact theory

weighted Probability Density Estimator with Updated Bandwidths

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Journal of systems science & Complexity 2024年第2期37卷 886-906页

作者： WU Yi YU wei WAnG Xuejun PRAKAsA RAO B L s school of Big Data and Artificial Intelligence Chizhou UniversityChizhou 247000China school of Big Data and statistics Anhui UniversityHefei 230601China CR Rao Advanced Institute of Mathematics Statistics and Computer ScienceHyderabad 500046India

In this paper,the authors study a class of weighted version of probability density *** is shown that the weighted estimator contains some existing estimators of probability density,no matter they are recursive or *** statistical results including weak consistency,strong consistency,rate of strong consistency,and asymptotic normality are established under some mild ***,the random weighted estimator is also *** numerical simulations and a real data analysis are pres.nted to study the numerical performances of the estimators.

关键词： Asymptotic normality consistency numerical simulation probability density real data analysis updated bandwidths weighted estimator

Morphological and biochemical characteristics associated with autophagy in gastrointestinal diseases

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World Journal of Gastroenterology 2024年第11期30卷 1524-1532页

作者： Yi-Fan Chang Jia-Jing Li Tao Liu Chong-Qing wei Li-wei Ma Vladimir n nikolenko wei-Long Chang Department of Gastrointestinal surgery The First Affiliated Hospital of Zhengzhou UniversityZhengzhou 450052Henan ProvinceChina Department of Pathology The First Affiliated Hospital of Zhengzhou UniversityZhengzhou 450052Henan ProvinceChina Department of Clinical Laboratory The First Affiliated Hospital of Zhengzhou UniversityZhengzhou 450052Henan ProvinceChina Department of Human Anatomy and Histology I.M.Sechenov First Moscow State Medical University(Sechenov University)Moscow 119991Russia

Autophagy is a cellular catabolic process characterized by the formation of double-membrane *** electron microscopy is the most rigorous method to clearly visualize autophagic engulfment and degradation.A large number of studies have shown that autophagy is closely related to the digestion,secretion,and regeneration of gastrointestinal(GI)***,the role of autophagy in GI diseases remains *** article focuses on the morphological and biochemical characteristics of autophagy in GI diseases,in order to provide new ideas for their diagnosis and treatment.

关键词： Autophagy Morphological study Biochemical characteristics subcellular structure Transmission electron microscopy Gastrointestinal diseases

Towards defining soil quality of Mediterranean calcareous agricultural soils:Reference values and potential core indicator set

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International soil and Water Conservation Research 2024年第1期12卷 145-155页

作者： Germán A.Durán Daniel sacristán Edelweis Farrús Jaume Vadell Institut de Recerca i FormacióAgrària i Pesquera de les Illes Balears C/Eusebi Estada14507009PalmaSpain Plant Biology Department University of Valencia46100BurjassotValenciaSpain soil and Environmental Quality Department Centro de Investigaciones sobre Desertificación-CIDE(CSIC-Universitat de València-Generalitat Valenciana)Carretera Moncada-Náquera km 4.546113MoncadaValenciaSpain Universitat de les Illes Balears Cra.De Valldemossakm 7507122PalmaSpain

To avoid soil degradation,adapt to climate change and comply with the sustainable Development goals 2030(Un General Assembly),establishing the quality/fertility of the agricultural soils of the Mediterranean region and evaluate how these evolve with time is *** enables adequate management practices to be *** Mediterranean calcareous region has received little attention in this s.nse,in spite its soil ***,24 different repres.ntative calcareous agricultural soils of the Mediterranean region,including the main management strategies of agricultural soils(rainfed and irrigated),were sampled from the island of Mallorca;and their physical,chemical and biological properties *** values obtained for most of the soil characteristics allowed to establish an initial approach to the reference values for the type of calcareous agricultural soils considered,and to clearly distinguish the effect of rainfed or irrigation management practices on soils properties and *** enzyme activities were not stimulated by the irrigation conditions assayed or they were only in dry conditions,suggesting optimum enzyme activities could be obtained when alternating dry and humid soil *** organic carbon,calcium carbonate and active lime revealed of significant importance in the collection of ***,the results obtained clearly indicate the heterogeneity of the region and its implications on the different soil ***,this study could serve as a starting point to adequately establish the quality(fertility)for Mediterranean calcareous agricultural soils and their reference values by conducting further research in this region and including more type of soils.

关键词： soil fertility Mediterranean agricultural soils Calcareous soils soil enzymes soil management

Bed inventory balance and stability of dual circulating fluidized bed systems

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Particuology 2024年第1期84卷 98-106页

作者： Yangjun wei Leming Cheng David Pallares Bo Leckner Institute for Thermal Power Engineering State Key Laboratory of Clean Energy UtilizationZhejiang UniversityHangzhou310027China Department of space Earth and EnvironmentChalmers University of TechnologyS-41296GöteborgSweden

Experiments and modelling are conducted for general understanding on the imbalance phenomenon and for discussion on the strategies to improve the bed inventory balance and stability of a dual circulating fluidized bed(DCFB)*** experiments are carried out in a 15.5 m high pilot-scale DCFB cold test system.A fluid-dynamic DCFB model is developed based on a 1.5-dimensional semi-empirical model of an industrial CFB boiler,validated by experimental *** effects of control methods and operation conditions on the bed inventory balance and on the stability of the pilot-and large-scale DCFB systems are discussed.A"stable-unbalanced"state,where the system reaches a steady state,consisting of un-balanced bed inventories,is observed in both experiments and model *** maintain a balanced state and similar bed inventory in the DCFB systems with similar cross-sectional areas,it is recom-mended to keep similar total pressure drops or gas velocities in both reactors.

关键词： Bed inventory balance stability Dual circulating fluidized bed(DCFB) Experiment Modelling

Early Phases of star Formation: Testing Chemical Tools

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Research in Astronomy and Astrophysics 2024年第1期24卷 96-118页

作者： n.C.Martinez s.Paron COnICET-Universidad de Buenos Aires.Instituto de Astronomía y Física del Espacio Ciudad Universitaria(C1428EGA)Ciudad Autónoma de Buenos AiresArgentina

star-forming processes strongly influence the IsM ***,many high-quality databases are available at millimeter *** them,it is possible to carry out studies that review and deepen previous *** these studies involve large samples of sources,it is preferred to use direct tools to study the molecular *** the aim of testing these tools such as the use of the HCn/HnC ratio as a thermometer,and the use of H^(13)CO^(+),HC_(3)n,n_(2)H^(+) and C_(2)H as "chemical clocks," we pres.nt a molecular line study toward 55 sources repres.nting massive young stellar objects at different evolutionary stages:infrared dark clouds(IRDCs),highmass protostellar objects(HMPOs),hot molecular cores(HMCs) and ultracompact H II *** found that the use of the HCn/HnC ratio as a universal thermometer in the IsM should be taken with care because the HCn optical depth is a big issue that can affect the ***,this tool should be utilized only after a careful analysis of the HCn spectrum,checking that no line,neither the main nor the hyperfine ones,pres.nts absorption *** point out that the analysis of the emission of H^(13)CO^(+),HC_(3)n,n_(2)H^(+) and C_(2)H could be useful to trace and distinguish regions among IRDCs,HMPOs and *** molecular line widths of these four species increase from the IRDC to the HMC stage,which can be a consequence of the gas dynamics related to the starforming processes taking place in the molecular *** results.not only contribute with more statistics,acting as a probe of such chemical tools,useful to obtain information in large samples of sources,but also complement previous works through the analysis of other types of sources.

关键词： stars:formation IsM:molecules IsM:clouds

Dispersion effect of nano-structure pyrolytic carbon on mechanical,electrical,and microstructural characteristics of cement mortar composite

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International Journal of smart and nano Materials 2024年第3期15卷 534-578页

作者： n.K.Karthikeyan s.Elavenil school of Civil Engineering Vellore Institute of TechnologyChennaiIndia

In material science,converting waste into nanomaterials by green technologies highlights the interest in producing sus-tainable carbon nanomaterial(s.n).This study first-ever uti-lized tyre-char as a nano-structure Pyrolytic Carbon(nsPC)to develop electrically conductive *** other car-bon nanomaterials,the efficiency of nsPC particle as an s.n in developing electrically conductive composites was investi-gated in terms of dispersion,mechanical,water absorption,electrical resistivity,and *** results of sedi-mentation and zeta potential(-19 mV)showed the excellent dispersion of nsPC particle in water with the combined effect of superplasticizer and *** compressive(40.37%)and flexural strength(10.76%)than that of plain cement mortar composite(CMC)is achieved with 2 wt.%and 1.5 wt.%of nsPC particle,*** water absorption rate and volume of permeable voids were reduced,exhibiting less *** percolation zone of AC and DC resis-tivity of nsPC composite ranges between 1 and 2 wt.%,and the established percolation threshold is at 2 wt.%.XRD analysis showed C-s-H formation consistently increased with curing age,and HR-sEM with EDAX analysis exhibits the dense micro-structure and well-distributed nsPC particle at the *** experimental outcomes significantly enhanced the relia-bility and provided a framework for tailoring nsPC particle as s.n for developing electrically conductive composite.

关键词： sustainable nanomaterial dispersion mechanical properties electrical resistivity microstructure analysis

Conformally symmetric wormhole solutions supported by non-commutative geometry in f(Q,T)gravity

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Communications in Theoretical Physics 2024年第2期76卷 111-124页

作者： Chaitra Chooda Chalavadi V Venkatesha n s Kavya s V Divya Rashmi Department of P.G.studies and Research in Mathematics Kuvempu UniversityShankaraghattaShivamogga 577451KarnatakaIndia Department of Mathematics Vidyavardhaka College of EngineeringMysuru—570002India

This paper investigates wormhole solutions within the framework of extended symmetric teleparallel gravity,incorporating non-commutative geometry,and conformal *** achieve this,we examine the linear wormhole model with anisotropic fluid under Gaussian and Lorentzian *** primary objective is to derive wormhole solutions while considering the influence of the shape function on model parameters under Gaussian and Lorentzian *** resulting shape function satisfies all the necessary conditions for a traversable ***,we analyze the characteristics of the energy conditions and provide a detailed graphical discussion of the matter contents via energy ***,we explore the effect of anisotropy under Gaussian and Lorentzian ***,we pres.nt our conclusions based on the obtained results.

关键词： traversable wormhole f(Q T)gravity energy conditions non-commutative geometry conformal motion