检索结果-南通市图书馆

GLOBAL WELL-POSEDNESS OF THE STOCHASTIC 2D BOUSSINESQ EQUATIONS WITH PARTIAL VISCOSITY

在线全文

学校读者我要写书评

暂无评论

Acta Mathematica Scientia 2011年第5期31卷 1968-1984页

作者：蒲学科郭柏灵 College of mathematics and statistics Chongqing University institute of applied Physics and Computational mathematics

This paper deals with the stochastic 2D Boussinesq equations with partial viscosity. This is a coupled system of Navier-Stokes/Euler equations and the transport equation for temperature under additive noise. Global we... 详细信息

关键词： stochastic PDEs Boussinesq equations global well-posedness

Galerkin Finite Element Study on the Effects of Variable Thermal Conductivity and Variable Mass Diffusion Conductance on Heat and Mass Transfer

在线全文

学校读者我要写书评

暂无评论

Communications in Theoretical Physics 2018年第7期69卷 49-59页

作者： Imran Haider Qureshi M.Nawaz Shafia Rana T.Zubair Department of applied mathematics and statistics Institute of Space and TechnologyIslamabad

This article investigates the effects of variable thermal conductivity and variable mass diffusion coefficient on the transport of heat and mass in the flow of Casson fluid. Numerical simulations for two-dimensional flow induced by stretching surface are performed by using Galerkin finite element method(GFEM) with linear shape functions. After assembly process, nonlinear algebraic equations are linearized through Picard method and resulting linear system is solved iteratively using Gauss Seidal method with simulation tolerance 10^(-8). Maximum value of independent variableη is searched through numerical experiments. Grid independent study was carried out and error analysis is *** results are validated by comparing with already published results. Parametric study is carried out to explore the physics of the flow. The concentration increases when mass diffusion coefficient is increased. The concentration and thermal boundary layer thicknesses increase when ?_1 and ? are increased. The effect of generative chemical reaction on concentration is opposite to the effect of destructive chemical reaction on the concentration.

关键词： variable diffusion coefficients grid independent study convergence error analysis Nusselt num-ber Casson fluid Joule heating viscous dissipation

Solutions of Ginzburg-Landau Theory for Atomic Fermi Gases Near the BCS-BEC Crossover

在线全文

学校读者我要写书评

暂无评论

Acta Mathematicae Applicatae Sinica 2015年第3期31卷 665-676页

作者： Shu-hong CHEN Bo-ling GUO School of mathematics and statistics Minnan Normal University institute of applied Physics and Computational mathematics

We are concerned with a time-dependent Ginzburg-Landau equations come from the superfluid atomic Fermi-gases near the Feshbach resonance from the fermion-boson model. We obtain the global existence and uniqueness of s... 详细信息

关键词： global existence uniqueness time-dependent Ginzburg-Landau theory BCS-BEC crossover

EFFECTIVE DYNAMICS OF A COUPLED MICROSCOPIC-MACROSCOPIC STOCHASTIC SYSTEM

在线全文

学校读者我要写书评

暂无评论

Acta Mathematica Scientia 2010年第6期30卷 2064-2076页

作者：任剑付红波曹道民段金桥 School of mathematics and statistics Huazhong University of Science and Technology institute of applied mathematics Chinese Academy of Sciences Department of applied mathematics Illinois Institute of Technology

A conceptual model for microscopic-macroscopic slow-fast stochastic systems is considered. A dynamical reduction procedure is presented in order to extract effective dynamics for this kind of systems. Under appropriate assumptions, the effective system is shown to approximate the original system, in the sense of a probabilistic convergence.

关键词： microscopic-macroscopic system stochastic partial differential equations averaging principle effective dynamics slow-fast scales

Joint Analysis of Recurrent Event Data with a Dependent Terminal Event

在线全文

学校读者我要写书评

暂无评论

Journal of Systems Science & Complexity 2017年第6期30卷 1443-1458页

作者： YE Peng DAI Jiajia ZHU Jun School of statistics University of International Business and Economics School of mathematics and statistics Guizhou University institute of applied mathematics Academy of Mathematics and Systems Science Chinese Academy of Sciences

Recurrent event data frequently occur in many longitudinal studies, and the observation on recurrent events could be stopped by a terminal event such as death. This paper considers joint modeling and analysis of recurrent event and terminal event data through a common subject-specific frailty, in which the proportional intensity model is used for modeling the recurrent event process and the additive hazards model is used for modeling the terminal event time. Estimating equation approaches are developed for parameter estimation and asymptotic properties of the resulting estimators are established. In addition, some procedures are presented for model checking. The finite sample behavior of the proposed estimators is evaluated through simulation studies, and an application to a heart failure study is provided.

关键词： Additive hazards model estimating equation frailty recurrent events terminal event

A CHARACTERIZATION OF ORTHONORMAL WAVELET FAMILIES IN SOBOLEV SPACES

在线全文

学校读者我要写书评

暂无评论

Acta Mathematica Scientia 2011年第4期31卷 1475-1488页

作者：鲁大勇李登峰 institute of applied mathematics College of Mathematics and Information Science Henan University College of mathematics and statistics Wuhan University

In this paper, a characterization of orthonormal wavelet families in Sobolev spaces H s （R） is established.

关键词： wavelets orthonormal wavelet families Sobolev spaces

Statistical Identification of Important Nodes in Biological Systems

在线全文

学校读者我要写书评

暂无评论

Journal of Systems Science & Complexity 2021年第4期34卷 1454-1470页

作者： WANG Pei School of mathematics and statistics Institute of Applied MathematicsLaboratory of Data Analysis TechnologyHenan UniversityKaifeng 475004China

Biological systems can be modeled and described by biological *** networks are typical complex networks with widely real-world *** problems arising in biological systems can be boiled down to the identification of important *** example,biomedical researchers frequently need to identify important genes that potentially leaded to disease phenotypes in animal and explore crucial genes that were responsible for stress responsiveness in *** facilitate the identification of important nodes in biological systems,one needs to know network structures or behavioral data of nodes(such as gene expression data).If network topology was known,various centrality measures can be developed to solve the problem;while if only behavioral data of nodes were given,some sophisticated statistical methods can be *** paper reviewed some of the recent works on statistical identification of important nodes in biological systems from three aspects,that is,1)in general complex networks based on complex networks theory and epidemic dynamic models;2)in biological networks based on network motifs;and 3)in plants based on RNA-seq *** identification of important nodes in a complex system can be seen as a mapping from the system to the ranking score vector of nodes,such mapping is not necessarily with explicit *** three aspects reflected three typical approaches on ranking nodes in biological systems and can be integrated into one general *** paper also proposed some challenges and future works on the related *** associated investigations have potential real-world applications in the control of biological systems,network medicine and new variety cultivation of crops.

关键词： Biological network complex network important node network motif RNA-seq

Complex transitions between spike, burst or chaos synchronization states in coupled neurons with coexisting bursting patterns

在线全文

学校读者我要写书评

暂无评论

Chinese Physics B 2015年第5期24卷 281-292页

作者：古华光陈胜根李玉叶 School of Aerospace Engineering and applied Mechanic Tongji University mathematics & statistics institute Chifeng University

We investigated the synchronization dynamics of a coupled neuronal system composed of two identical Chay model neurons. The Chay model Showed coexisting period-1 and period-2 bursting patterns as a parameter and initial values are varied. We simulated multiple periodic and chaotic bursting patterns with non-（NS）, burst phase （BS）, spike phase （SS）, complete （CS）, and lag synchronization states. When the coexisting behavior is near period-2 bursting, the transitions of synchronization states of the coupled system follows very complex transitions that begins with transitions between BS and SS, moves to transitions between CS and SS, and to CS. Most initial values lead to the CS state of period-2 bursting while only a few lead to the CS state of period-I bursting. When the coexisting behavior is near period-1 bursting, the transitions begin with NS, move to transitions between SS and BS, to transitions between SS and CS, and then to CS. Most initial values lead to the CS state of period-1 bursting but a few lead to the CS state of period-2 bursting. The BS was identified as chaos synchronization. The patterns for NS and transitions between BS and SS are insensitive to initial values. The patterns for transitions between CS and SS and the CS state are sensitive to them. The number of spikes per burst of non-CS bursting increases with increasing coupling strength. These results not only reveal the initial value- and parameter- dependent synchronization transitions of coupled systems with coexisting behaviors, but also facilitate interpretation of various bursting patterns and synchronization transitions generated in the nervous system with weak coupling strength.

关键词： synchronization transition phase synchronization coexisting attractors coupled neuronal system

A Class of Stable and Conservative Finite Difference Schemes for the Cahn-Hilliard Equation

在线全文

学校读者我要写书评

暂无评论

Acta Mathematicae Applicatae Sinica 2015年第4期31卷 863-878页

作者： Ting-chun WANG Li-mei ZHAO Bo-ling GUO School of mathematics and statistics Nanjing University of Information Science and Technology institute of applied Physics and Computational mathematics

In this paper, we propose a class of stable finite difference schemes for the initial-boundary value problem of the Cahn-Hilliard equation. These schemes are proved to inherit the total mass conservation and energy dissipation in the discrete level. The dissipation of the total energy implies boundness of the numerical solutions in the discrete H1 norm. This in turn implies boundedness of the numerical solutions in the maximum norm and hence the stability of the difference schemes. Unique existence of the numerical solutions is proved by the fixed-point theorem. Convergence rate of the class of finite difference schemes is proved to be O（h2 ＋ r2） with time step T and mesh size h. An efficient iterative algorithm for solving these nonlinear schemes is proposed and discussed in detail.

关键词： Cahn-Hilliard equation finite difference scheme conservation of mass dissipation of energy convergence iterative algorithm