检索结果-南通市图书馆

Particuology 2012年第6期10卷 672-682页

作者： r.Baleviius I.Sielamowicz Z.Mróz r.kaianauskas Department of reinforced Concrete and Masonry Structures Vilnius Gediminas Technical Universityav.Sauletekio 11LT-10223 VilniusLithuania Composite Silo Systems OrCHIDEA st.J.Matejki 815-196 BialystokPoland Institute of Fundamental Technological research Polish Academy of Sciencesst.Pawin'skiego 5b02-106 WarsawPoland Institute of Mechanics Vilnius Gediminas Technical Universityst.J.Basanaviiaus.28LT-10223 VilniusLithuania

The present paper provides both experimental and DEM analyses of the filling and discharge of pea grains from a 3D flat-bottomed bin. In the DEM model, the fixed mean values of the experimentally determined single particle data, such as the particle density, Young＇s modulus, Poisson＇s ratio as well as the sliding and rolling friction coefficients were incorporated to analyse their effects on the macroscale indicators, such as the wall pressure, discharge velocities and material outflow parameters. The effect of rolling friction was studied based on the experimentally measured single particle rolling friction coefficient. This analysis is aimed at the quantitative prediction of flow parameters as related to the identification of material parameters.

关键词： Visco-elastic granular materia Discrete element method rolling friction Wall pressure Material velocityOutflow mass Outflow rateBiosystems Pea grains

De novo synthesis of atropisomeric benzofurans via Cu/SPDO complex catalyzed asymmetric formal [3 + 2] annulation

在线全文

学校读者我要写书评

暂无评论

Science China Chemistry 2025年第1期 174-180页

作者： Fan-Xiao Meng Xing-Yu Wang ka Lu Ju-Song Yang Fu-Min Zhang Ai-Jun Ma Bao Du Yong-Qiang Tu State Key Laboratory of Applied Organic Chemistry College of Chemistry and Chemical Engineering Lanzhou University School of Chemistry and Chemical Engineering Shanghai Jiao Tong University School of Biotechnology and Health Sciences Wuyi University

Herein, the de novo synthesis of atropisomeric benzofurans through the Cu/spirocyclic-pyrrolidine-oxazoline(SPDO) complex catalyze asymmetric formal [3 + 2] cycloaddition between quinones and ynamides is explored, producing a range of structurally diverse axially chiral benzofurans in satisfactory yields with good to excellent enantioselectivities. Furthermore, density functional theory calculations were applied to explain the possible reaction mechanism.

关键词：

同方期刊数据库

Machine Learning Techniques in Predicting Hot Deformation Behavior of Metallic Materials

在线全文

学校读者我要写书评

暂无评论

Computer Modeling in Engineering & Sciences 2025年第1期142卷 713-732页

作者： Petr Opela Josef Walek Jaromír Kopecek Department of Metallurgical Technologies Faculty of Materials Science and TechnologyVSB–Technical University of OstravaOstrava70800Czech Republic FZU—Institute of Physics of the Czech Academy of Sciences Prague18200Czech Republic

In engineering practice,it is often necessary to determine functional relationships between dependent and independent *** relationships can be highly nonlinear,and classical regression approaches cannot always provide sufficiently reliable ***,Machine Learning(ML)techniques,which offer advanced regression tools to address complicated engineering issues,have been developed and widely *** study investigates the selected ML techniques to evaluate their suitability for application in the hot deformation behavior of metallic *** ML-based regression methods of Artificial Neural Networks(ANNs),Support Vector Machine(SVM),Decision Tree regression(DTr),and Gaussian Process regression(GPr)are applied to mathematically describe hot flow stress curve datasets acquired experimentally for a medium-carbon *** the GPr method has not been used for such a regression task before,the results showed that its performance is the most favorable and practically unrivaled;neither the ANN method nor the other studied ML techniques provide such precise results of the solved regression analysis.

关键词： Machine learning Gaussian process regression artificial neural networks support vector machine hot deformation behavior

Emerging potential of progranulin-dependent SorCS2 signaling in healthy and diseased nervous systems

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Neural regeneration research 2025年第9期20卷 2591-2593页

作者： Alena Salasova Anders Nykjær Danish research Institute of Translational Neuroscience DANDrITE-Nordic EMBL Partnership for Molecular Medicine and Centre of Excellence PROMEMODepartment of BiomedicineAarhus UniversityAarhusDenmark

The formation of the mammalian nervous system and its maturation into sensory,motor,cognitive,and behavioral circuits is a complex process that begins during early embryogenesis and lasts until young *** neurodevelopm... 详细信息

关键词： progr jointly CS2

A comprehensive investigation on nonlinear vibration and bending characteristics of bio-inspired helicoidal laminated composite structures

在线全文

学校读者我要写书评

暂无评论

Applied Mathematics and Mechanics(English Edition) 2025年第1期46卷 81-100页

作者： S.SAUrABH r.KIrAN D.SINGH r.VAISH V.S.CHAUHAN School of Mechanical and Materials Engineering Indian Institute of Technology Mandi

Bio-inspired helicoidal composite laminates, inspired by the intricate helical structures found in nature, present a promising frontier for enhancing the mechanical properties of structural designs. Hence, this study provides a comprehensive investigation into the nonlinear free vibration and nonlinear bending behavior of bio-inspired composite plates. The inverse hyperbolic shear deformation theory(IHSDT) of plates is employed to characterize the displacement field, with the incorporation of Green-Lagrange nonlinearity. The problem is modeled using the C0finite element method(FEM), and an in-house code is developed in the MATLAB environment to solve it numerically. Various helicoidal layup configurations including helicoidal recursive(Hr), helicoidal exponential(HE), helicoidal semi-circular(HS), linear helicoidal(LH), and Fibonacci helicoidal(FH)with different layup sequences and quasi-isotropic configurations are studied. The model is validated, and parametric studies are conducted. These studies investigate the effects of layup configurations, side-to-thickness ratio, modulus ratios, boundary conditions, and loading conditions at different load amplitudes on the nonlinear vibration and nonlinear bending behaviors of bio-inspired composite plates. The results show that the laminate sequence exerts a substantial impact on both nonlinear natural frequencies and nonlinear bending behaviors. Moreover, this influence varies across different side-to-thickness ratios and boundary conditions of the bio-inspired composite plate.

关键词：

Antisense oligonucleotides provide optimism to the therapeutic landscape for tauopathies

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Neural regeneration research 2025年第3期20卷 803-804页

作者： Glenn A.Harris Lauren r.Hirschfeld rainwater Charitable Foundation Fort WorthTXUSA

Tauopathies are a group of neurodegenerative diseases characterized by abnormal metabolism of the misfolded tau protein. Tau is encoded by the microtubule-associated protein tau gene(MAPT) and can be classified as either 3-repeat(3r) or 4-repeat(4r) based on the number of repeat domains from alternative splicing of exon 10 of the MAPT gene.

关键词： tau metabolism diseases

Tribonacci Partition Formulas Modulo m

在线全文

学校读者我要写书评

暂无评论

Acta Mathematica Sinica,English Series 2010年第3期26卷 465-476页

作者： Ji■í KLA■ka Institute of Mathematics Brno University of Technology

Each Tribonacci sequence starting with an arbitrary triple of integers is periodic modulo m for any modulus m 〉 1. For a given m, the mapping between the set S of all m^3 triples of initial values and the set of their coresponding periods define a partition of the set S. In this paper we shall investigate some basic questions related to these partitions from the point of view of enumerative combinatorics.

关键词： Tribonacci sequence modular periodicity partition formulas

Computational design of structured chemical products

在线全文

学校读者我要写书评

暂无评论

Frontiers of Chemical Science and Engineering 2021年第5期15卷 1033-1049页

作者： Faheem Mushtaq Xiang Zhang ka Y.Fung ka M.Ng Department of Chemical and Biological Engineering The Hong Kong University of Science and TechnologyHong KongChina

In chemical product design,the aim is to formulate a product with desired *** and internal product structure are two key drivers of product performance with direct impact on the mechanical,electrical,and thermal ***,there is a keen interest in elucidating the dependence of product performance on ingredients,structure,and the manufacturing process to form the *** of product structure,particularly microstructure,is an intrinsically complex problem that involves different phases of different physicochemical properties,mass fraction,morphology,size distribution,and ***,computational methods have emerged that assist systematic microstructure quantification and *** objective of this paper is to review these computational methods and to show how these methods as well as other developments in product design can work seamlessly in a proposed performance,ingredients,structure,and manufacturing process framework for the design of structured chemical *** begins with the desired target properties and key *** is followed by computation for microstructure and then selection of processing steps to realize this *** framework is illustrated with the design of nanodielectric and die attach adhesive products.

关键词： product design performance ingredients structure manufacturing process framework structured chemical products microstructure design

All-parameters rayleigh wave inversion

在线全文

学校读者我要写书评

暂无评论

Earthquake Engineering and Engineering Vibration 2021年第2期20卷 517-534页

作者： Xiao-Hui Yang ka-Veng Yuen State Key Laboratory of Internet of Things for Smart City and Department of Civil and Environmental Engineering University of MacaoMacao 999078China

Since S-wave velocity of the subsurface is an important parameter in near surface applications,many studies have been conducted for its *** the various methods that use surface waves or body waves,rayleigh wave inversion is the most *** practice,the densities and P-wave velocities of different layers are usually assumed to be known to avoid ill-posed problems,as they have less influence on the dispersion ***,improper assignment of these two groups of parameters leads to inaccurate estimation of the S-wave velocity *** order to address this problem,the all-parameters rayleigh wave inversion strategy is proposed in which the S-wave velocities,layer thicknesses,densities and P-wave velocities of different layers are included as the unknown parameters for ***,the transitional Markov Chain Monte Carlo(TMCMC)algorithm is applied for the implementation of all-parameters rayleigh wave *** simulated example and two real-test applications are demonstrated to verify the capability of the proposed method in the estimation of the S-wave velocity profile,the densities and the P-wave ***,it is verified that the proposed method achieved more accurate S-wave velocity profile estimation than the traditional approach.

关键词： all-parameters rayleigh wave inversion Bayesian S-wave velocity profile TMCMC algorithm uncertainty quantification

The Most General Corrdinate Transformation Between the Hydrogen Atom and Harmonic Oscillator in Arbitrary Dimensions

在线全文

学校读者我要写书评

暂无评论

Chinese Physics Letters 1997年第10期14卷 721-723页

作者： SU ka-lin Department of Physics Yueyang Normal CollegeYueyang 414000

In this paper,we find out the most general coordinate transformation between a d-dimensional hydrogen atom and a D-dimensional harmonic oscillator by means of the SU(1,l)*** other words,the generalized Kustaanheimo-St... 详细信息

关键词： algebra Transformation coordinate