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SmALL DEnSITY FLUCTUTAIOn FOR OnE DImEnSIOnAL COnTACT PROCESSES UnDER nOnEQUILIBRIUm

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Acta mathematica Scientia 1993年第4期13卷 399-405页

作者：陈金文 Dept. of math. Beijing Norm. Univ. Beijing 100875 China

This paper shows that for a supercritical contact process in one dimension, if the initial distribution satisfies reasonable hypothesis, then the first hitting time of certain set with anomalous small density is asymptotically exponentially distributed. We also show the similar result for the contact process on the finite set [0, n].

关键词： SmALL DEnSITY FLUCTUTAIOn FOR OnE DImEnSIOnAL COnTACT PROCESSES UnDER nOnEQUILIBRIUm Za 带刀 Th

Coping with drought?Effects of extended drought conditions on soil invertebrate prey and diet selection by a fossorial amphisbaenian reptile

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Current Zoology 2023年第4期69卷 367-376页

作者： José martín Jesús Ortega Roberto García-Roa Gonzalo Rodríguez-Ruiz Ana Pérez-Cembranos Valentín Pérez-mellado Departamento de Ecología Evolutiva Museo Nacional de Ciencias NaturalesCSICMadridSpain Institute of Evolutionary Biology CSIC-Universitat Pompeu FabraBarcelonaSpain Ethology Lab Cavanilles Institute of Biodiversity and Evolutionary BiologyUniversity of ValenciaValenciaSpain Departamento de Biología Animal Universidad de SalamancaSalamancaSpain

Arid climates are characterized by a summer drought period to which animals seem ***,in some years,the drought can extend for unusually longer *** the effects of these current extreme weather events on biodiversity can help to understand the effects of climate change,as models predict an increase in drought ***,we examined the effects of“unusual”extended drought on soil invertebrate prey availability and on diet composition(based on fecal contents)and diet selection of a fossorial amphisbaenian,the checkerboard worm lizard Trogonophis *** data show interannual variations in summer drought *** abundance and diversity of soil invertebrates in spring were high,and similar to those found in a“normal”early autumn,after some rain had ended with the summer *** contrast,in years with“unusual”extended drought,abundance,and diversity of soil invertebrates in early autumn were very ***,there were seasonal changes in amphisbaenians’diet;in autumn with drought,prey diversity,and niche breadth decreased with respect to spring and autumns after some rain had *** did not eat prey at random in any season,but made some changes in prey selection that may result from drought-related restrictions in prey ***,in spite that amphisbaenians showed some feeding flexibility,their body condition was lower in autumn than in spring,and much lower in autumn with *** extended drought became the norm in the future,amphisbaenians might suffer important negative effects for their health state.

关键词： amphisbaenians drought feeding ecology soil invertebrates Trogonophis wiegmanni weather conditions

COEFFICIEn　TCOnDITIOnS　OF　LOCALLY　TOPOLOGICAL　STRUCTURE　FOR　nOnLInEAR　HOmOGEnEOUS　SYSTEm　WITH　ZERO　CHARACTERISTIC　ROOTS

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Acta mathematica Scientia 1995年第S1期15卷 70-81页

作者：李学敏 Dept. of math. Shandong Norm. Univ. Jinan 250014 China

In this paper, we discuss the locally topological structure for nonlinear homogeneous n-degree system with zero characteristic roots, and give a criteria by the coefficients of the polynonmials.

关键词： nonlinear system higher order singular point topological structure.

On THE EXISTEnCE AnD nODAL CHARACTER OF THE SOLUTIOnS OF SInGULAR nOnLInEAR BOUnDARY VALUE PROBLEmS

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Acta mathematica Scientia 1991年第4期11卷 443-461页

作者：曹道珉邓引斌 Inst. of math. Sci. Academia Sinica Wuhan China Dept. of math. Huazhong Norm. Univ. Wuhan China

1. Introduction We consider the singular nonlinear boundary value problem where l=v+3/v-1,l+1 is the critical exponent of the embedding of weighted Sobolev space Wt21,2（O, +∞） into Lt2q（O, ∞）, v>2. When v=n-1 we can get the radial solutions of problem where 2*=2n/n-2 is the critical exponent of the Sobolev embedding H1（Rn）→LQ（Rn）. Kurtz has discussed the existence of κ-node solution of （1.1）, （1.2） for each κ∈n Un when the growth rate of |u|l-1u+f（u） is lower then |u|v+3/v-1 i.e.

关键词： On THE EXISTEnCE AnD nODAL CHARACTER OF THE SOLUTIOnS OF SInGULAR nOnLInEAR BOUnDARY VALUE PROBLEmS

m.B.积分、B.E.积分、F.D.积分及其应用

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四川师范大学学报（自然科学版） 1989年第2期12卷 63-68页

作者：谢应华四川师范大学物理系

本文给出了麦免斯韦—玻耳兹曼积分(m.B.积分)、玻色—爱因斯坦积分(B.E.积分)和费密—狄拉克积分(F.D.积分)的计算公式,并应用这些积分公式对经典理想气体、理想玻色气体和理想费密气体的主要热力学量进行了计算。其特点是对经典系统... 详细信息

本文给出了麦免斯韦—玻耳兹曼积分(m.B.积分)、玻色—爱因斯坦积分(B.E.积分)和费密—狄拉克积分(F.D.积分)的计算公式,并应用这些积分公式对经典理想气体、理想玻色气体和理想费密气体的主要热力学量进行了计算。其特点是对经典系统和量子系统都给出了统一的表述形式。

关键词： m.B.积分 B.E.积分 F.D.积分

Laser speckle contrast imaging for monitoring of acutepancreatitis at ischemia-reperfusion injury of thepancreas in rats

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Journal of Innovative Optical Health Sciences 2022年第1期15卷 90-102页

作者： P.A.Dyachenko(Timoshina) A.n.Bashkatov D.A.Alexandrov V.I.Kochubey V.V.Tuchin Saratov State University SaratovRussia Laboratories of Biophotonics and Laser molecular Imaging and machine Learning national Research Tomsk State University TomskRussia Saratov State medical University SaratovRussia Institute of Precision mechanics and Control Russian Academy of SciencesRussia A.n.Bach Institute of Biochemistry Research Center of Biotechnology of the Russian Academy of Sciences MoscowRussia

The influence of ischemia-reperfusion(I/R)action on pancreatic blood flow(PBF)and the development of acute pancreatitis(AP)in laboratory rats is evaluated in vivo by using the laser speckle contrast imaging(LSCI).Additionally,the optical properties in norm and under condition of AP in rats were assessed using a modied integrating sphere spectrometer and inverse monte Carlo(ImC)*** results of the experimental study of microcirculation of the pancreas in 82 rats in the ischemic model are *** data obtained conrm the fact that local ischemia and changes in the blood°ow velocity of the main vessels cause and provoke acute pancreatitis.

关键词： Laser speckles contrast of speckle images adaptive algorithm microcirculation blood flow acute pancreatitis pancreas rats optical properties integrating sphere spectroscopy

WEIGHTED InEQUALITIES AnD APPLICATIOnS TO BEST LOCAL APPROXImATIOn In LUXEmBURG norm

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Analysis in Theory and Applications 2004年第3期20卷 265-280页

作者： H.H.Cuenya m.D.Lorenzo C.n.Rodriguez Universidad nacional de Rio Cuarto ArgentinaUniversidad Nacional de Rio CuartoArgentinaUniversidad Nacional de Rio CuartoArgentina

In this paper we establish a result about uniformly equivalent norms and the convergence of best approximant pairs on the unitary ball for a family of weighted Luxemburg norms with normalized weight functions depending on ε, when ε→ 0. It is introduced a general concept of Pade approximant and we study its relation with the best local quasi-rational approximant. We characterize the limit of the error for polynomial approximation. We also obtain a new condition over a weight function in order to obtain inequalities in Lp norm, which play an important role in problems of weighted best local Lp approximation in several variables.

关键词： weighted Luxemburg norm best local aproximation Fade approximant

Large-Scale Estimation of Distribution Algorithms with Adaptive Heavy Tailed Random Pro jection Ensembles

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Journal of Computer Science & Technology 2019年第6期34卷 1241-1257页

作者： momodou L.Sanyang Ata Kabán School of Computer Science University of BirminghamEdgbastonBirmingham B152TTU.K. School of Information Technology and Communication University of The GambiaSerekundaThe Gambia

We present new variants of Estimation of Distribution Algorithms (EDA) for large-scale continuous optimisation that extend and enhance a recently proposed random projection (RP) ensemble based approach. The main novelty here is to depart from the theory of RPs that require (sub-)Gaussian random matrices for norm-preservation, and instead for the purposes of high-dimensional search we propose to employ random matrices with independent and identically distributed entries drawn from a t-distribution. We analytically show that the implicitly resulting high-dimensional covariance of the search distribution is enlarged as a result. moreover, the extent of this enlargement is controlled by a single parameter, the degree of freedom. For this reason, in the context of optimisation, such heavy tailed random matrices turn out to be preferable over the previously employed (sub-)Gaussians. Based on this observation, we then propose novel covariance adaptation schemes that are able to adapt the degree of freedom parameter during the search, and give rise to a flexible approach to balance exploration versus exploitation. We perform a thorough experimental study on high-dimensional benchmark functions, and provide statistical analyses that demonstrate the state-of-the-art performance of our approach when compared with existing alternatives in problems with 1000 search variables.

关键词： covariance adaptation estimation of distribution algorithm random projection ensemble t-distribution

A Third Order Accurate in Time,BDF-Type Energy Stable Scheme for the Cahn-Hilliard Equation

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numerical mathematics(Theory,methods and Applications) 2022年第2期15卷 279-303页

作者： Kelong Cheng Cheng Wang Steven m.Wise Yanmei Wu School of Science Southwest University of Science and TechnologyMianyangSichuan 621010P.R.China Department of mathematics The University of MassachusettsNorth DartmouthMA 02747USA Department of mathematics The University of TennesseeKnoxvilleTN 37996USA

In this paper we propose and analyze a backward differentiation formula(BDF)type numerical scheme for the Cahn-Hilliard equation with third order temporal *** Fourier pseudo-spectral method is used to discretize *** surface diffusion and the nonlinear chemical potential terms are treated implicitly,while the expansive term is approximated by a third order explicit extrapolation formula for the sake of *** addition,a third order accurate Douglas-Dupont regularization term,in the form of−A_(0)△t^(2)△_( n)(φ^(n+1)−φ^(n)),is added in the numerical *** particular,the energy stability is carefully derived in a modified version,so that a uniform bound for the original energy functional is available,and a theoretical justification of the coefficient A becomes *** a result of this energy stability analysis,a uniform-in-time L_(n)^(6)bound of the numerical solution is *** also,the optimal rate convergence analysis and error estimate are provided,in the L_(△t)^(∞)(0,T;L_(n)^(2))∩L^(2)_(△ t)(0,T;H_(h)^(2))norm,with the help of the L_(n)^(6)bound for the numerical solution.A few numerical simulation results are presented to demonstrate the efficiency of the numerical scheme and the third order convergence.

关键词： Cahn-Hilliard equation third order backward differentiation formula unique solvability energy stability discrete L6 n estimate optimal rate convergence analysis