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A novel simple procedure to consider seismic soil structure interaction effects in 2D models

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Earthquake Engineering and Engineering Vibration 2014年第3期13卷 535-543页

作者： juan Diego Jaramillo juan David Gómez Doriam Restrepo Santiago Rivera Universidad EAFIT Medellín Colombia INTEGRAL S.A Medellín Colombia

A method is proposed to estimate the seismic soil-structure-interaction （SSI） effects for use in engineering practice. It is applicable to 2D structures subjected to vertically incident shear waves supported by homogenous half-spaces. The method is attractive since it keeps the simplicity of the spectral approach, overcomes some of the difficulties and inaccuracies of existing classical techniques and yet it considers a physically consistent excitation. This level of simplicity is achieved through a response spectra modification factor that can be applied to the free-field 5%-damped response spectra to yield design spectral ordinates that take into account the scattered motions introduced by the interaction effects. The modification factor is representative of the Transfer Function （TF） between the structural relative displacements and the free- field motion, which is described in terms of its maximum amplitude and associated frequency. Expressions to compute the modification factor by practicing engineers are proposed based upon a parametric study using 576 cases representative of actual structures. The method is tested in 10 cases spanning a wide range of common fundamental vibration periods.

关键词： seismic soil structure interaction simplified procedures modified response spectra

Models and observations of sunspot penumbrae

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Science China(Physics,Mechanics & Astronomy) 2009年第11期52卷 1670-1677页

作者： BORRERO juan Manuel Max Planck Institut fr Sonnensystemforschung Max Planck Strasse 2 D 37191 Katlenburg-Lindau Germany

The mysteries of sunspot penumbrae have been under an intense scrutiny for the past 10 years. During this time, some models have been proposed and refuted, while the surviving ones had to be modified, adapted and evolved to explain the ever-increasing array of observational constraints. In this contribution I will review two of the present models, emphasizing their contributions to this field, but also pinpointing some of their inadequacies to explain a number of recent observations at very high spatial resolution (0.32 ). To help explaining these new observations I propose some modifications to each of those models. These modifications bring those two seemingly opposite models closer together into a general picture that agrees well with recent 3D magneto-hydrodynamic simulations.

关键词： sunspots magnetic fields spectropolarimetry magnetohydrodynamics

Some Smoothness Results for Classical Problems in Optimal Design and Applications

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Chinese Annals of Mathematics,Series B 2015年第5期36卷 703-714页

作者： juan CASADO-DIAZ Dpto.de Ecuaciones Diferenciales y Analisis Numerico University of Seville41012 SevillaSpain

The author considers two classical problems in optimal design consisting in maximizing or minimizing the energy corresponding to the mixture of two isotropic materials or two-composite material. These results refer to... 详细信息

关键词： Optimal design Two-phase material Non-existence Relaxation

Asymptotic of Eigenvalues and Lattice Points

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Acta Mathematica Sinica,English Series 2006年第6期22卷 1645-1650页

作者： juan Pablo PINASCO Instituto de Ciencias Universidad Nacional de General Sarmiento

dimension. elementary domains of In this work we study the spectral counting function for the p-Laplace operator in one We show the existence of a two-term Weyl-type asymptote. The method of proof is rather based on ... 详细信息

关键词： p-Laplacian eigenvalues lattice points

Fibonacci Sequences and the Multiperiodicity of the Variable Star UW Herculis

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Chinese Journal of Astronomy and Astrophysics 2003年第3期3卷 235-240页

作者： juan Garcia Escudero Departamento de Fisica Universidad de Oviedo 33007 Oviedo Spain

We present an application of the methods recently developed for the study of quasicrystal structures to the analysis of multiperiodicity of semiregular variables. A light curve analysis of UW Her shows frequencies that can be included within the general scheme characterizing the Fourier spectra of Fibonacci quasiperiodic sequences. The analysed data come from the BAA Variable Star Section computerised archive.

关键词： stars: variables

Characteristics of the dynamic distribution of suspended particles in the flocculation process

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2009年第9期10卷 1350-1358页

作者： Jun NAN Wei-peng HE juan-juan SONG Gui-bai LI State Key Laboratory of Urban Water Resource and Environment School of Municipal and Environmental Engineering Harbin Institute of Technology Harbin 150090 China

Polyaluminium chloride (PAC) synthetic water was selected as a coagulant and kaolin suspension particles as objects to be removed. Online instruments such as the turbidimeter and particle counter were employed to monitor the flocculation process online and collect test data. The aim of the experiments was to study the dynamic distribution characteristics of suspension particles in the flocculation process. The 3D flow field in the reacting vessel was also simulated at different slow stirring speeds. The experiments showed that particle collision and aggregation in the flocculation process is in compliance with the Sutherland cluster aggregation model. This study further indicated that under appropriate hydrodynamic conditions, the distribution of turbulent flow in the reactor could be improved to increase the odds of effective particle collision and restrain the breakup of formed flocs by vortex shearing force. A good flocculation effect could therefore be produced.

关键词： Suspension particle Particle counter Flocculation process Dynamic distribution

Powers of General Digital Sums

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Acta Mathematica Sinica,English Series 2010年第6期26卷 1133-1138页

作者： Feng juan CHEN School of Mathematical Sciences Nanjing Normal University Nanjing 210046 P. R. China and Department of Mathematics Suzhou University Suzhou 215006 P. R. China

Let m0,m1,m2,…be positive integers with mi〉 2 for all i. It is well known that each nonnegative integer n can be uniquely represented as n= a0 ＋ a1m0＋a2m0m1＋…＋atm0m1m2…mt-1,where 0≤ai≤mi-1 for all i and at≠*** each fi be a function defined on {0,1,2…,mi-1} with fi（0）=*** S（n）=i=0∑tfi（ai）.In this paper, we give the asymptotic formula for x^-1∑n≤xS（n）^k,where k is a positive integer.

关键词： digital sum arithmetic function asymptotic formula

ON THE CAUCHY PROBLEM FOR AW-RASCLE SYSTEM WITH LINEAR DAMPING

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Acta Mathematica Scientia 2021年第1期41卷 311-318页

作者： juan C.JUAJIBIOY Escuela de Matemdticas y Estadistica Universidad Pedagogica y Tecnològica de ColombiaTunja 15001BoyacaColombia

The existence of global BV solutions for the Aw-Rascle system with linear damping is *** order to get approximate solutions we consider the system in Lagrangian coordinates,then by using the wave front tracking method coupling with and suitable splitting algorithm and the ideas of[1]we get a sequence of approximate *** we show the convergence of this approximate sequence to the weak entropic solution.

关键词： wave front tracking global weak entropy solutions linear damping

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Plant Diversity 2021年第2期43卷 111-116页

作者： juan Yue Rong Li CAS Key Laboratory for Plant Diversity and Biogeography of East Asia Kunming Institute of BotanyChinese Academy of SciencesKunming650201China University of Chinese Academy of Sciences Beijing100049China

The species composition of plant communities is determined by a number of factors,including current environmental conditions as well as biogeographical and evolutionary *** evidence that plant diversity decreases and species relatedness increases along latitudinal and environmental gradients(e.g.,low temperatures),it remains unclear whether these same patterns occur along elevational gradients,especially in the subtropical mountainous areas harboring rich *** this study,we explored the pattern of phylogenetic relatedness of woody angiosperm assemblages and examined the effects of temperature variables on the phylogenetic relatedness among angiosperm woody plants using generalized linear model in subtropical forest communities along a broad elevational gradient in the Dulong Valley of Yunnan Province,*** results showed that woody angiosperm species in local forest plots tend to be more phylogenetically related at higher elevations and in areas with lower ***,winter average temperature,rather than mean annual temperature,is a major predictor of the pattern of increasing phylogenetic relatedness with increasing *** finding is consistent with the prediction of‘Tropical Niche Conservatism’hypothesis,which highlights the role of niche constraints in driving phylogenetic community assembly along an elevational gradient.

关键词： Dulong Valley Ecological tolerance Habitat filtering Niche conservatis