检索结果-南通市图书馆

THE RIEMANN PROBLEM FOR ISENTROPIC COMPRESSIBLE EULER EQUATIONS WITH DISCONTINUOUS FLUX

在线全文

学校读者我要写书评

暂无评论

Acta Mathematica Scientia 2024年第1期44卷 37-77页

作者：孙印正屈爱芳袁海荣 department of mathematics Shanghai Normal UniversityShanghai200234China School of Mathematical Sciences and Shanghai Key Laboratory of Pure mathematics and Mathematical Practice East China Normal UniversityShanghai200241China

We consider the singular Riemann problem for the rectilinear isentropic compressible Euler equations with discontinuous flux,more specifically,for pressureless flow on the left and polytropic flow on the right separated by a discontinuity x=x(t).We prove that this problem admits global Radon measure solutions for all kinds of initial *** over-compressing condition on the discontinuity x=x(t)is not enough to ensure the uniqueness of the ***,there is a unique piecewise smooth solution if one proposes a slip condition on the right-side of the curve x=x(t)+0,in addition to the full adhesion condition on its *** an application,we study a free piston problem with the piston in a tube surrounded initially by uniform pressureless flow and a polytropic *** particular,we obtain the existence of a piecewise smooth solution for the motion of the piston between a vacuum and a polytropic *** indicates that the singular Riemann problem looks like a control problem in the sense that one could adjust the condition on the discontinuity of the flux to obtain the desired flow field.

关键词： compressible Euler equations Riemann problem Radon measure solution delta shock discontinuous flux wave interactions

∞-Tilting Subcategories in Extriangulated Categories

在线全文

学校读者我要写书评

暂无评论

Chinese Annals of mathematics,Series B 2024年第1期45卷 151-160页

作者： Zhen ZHANG Jiaqun WEI Shance WANG department of mathematics Qilu Normal UniversityJinan 250200China Institution of mathematics School of Mathematics ScienceNanjing Normal UniversityNanjing 210023China

In this paper, the authors introduce a new definition of ∞-tilting(resp. cotilting) subcategories with infinite projective dimensions(resp. injective dimensions) in an extriangulated category. They give a Bazzoni characterization of ∞-tilting(resp. cotilting)subcategories. Also, they obtain a partial Auslander-Reiten correspondence between ∞-tilting(resp. cotilting) subcategories and coresolving(resp. resolving) subcategories with an E-projective generator(resp. E-injective cogenerator) in an extriangulated category.

关键词： Extriangulated category ∞-Tilting subcategory Auslander-Reiten correspondence Bazzoni characterization

Wobbling motion for a triaxial rotor plus a single quasiparticle

在线全文

学校读者我要写书评

暂无评论

Chinese Physics C 2024年第3期48卷 104-117页

作者：李嗣华戴华名陈启博周先荣 department of Physics East China Normal UniversityShanghai 200241China

Wobbling motion in a system comprising a triaxial rotor and a single quasiparticle is studied employing the particle-rotor *** energy spectra,wobbling frequencies,electromagnetic transition probabilities,g-factors,angular momentum components,spin coherent state maps,and static quadrupole moments are *** investigations were conducted with regard to the Fermi surface transitioning from the lowest h_(11/2) orbit to the highest *** the Fermi surface increases,notable transformations occur in the wobbling ***,the mode exhibits a transverse revolution around the short axis of the ***,as the Fermi surface continues to increase,the mode gradually shifts to a longitudinal revolution around the intermediate ***,it transitions to a transverse revolution around the long ***,the stability of the long axis transverse mode diminishes relative to its counterpart along the short axis as the total angular momentum increases atγ=20∘.

关键词： Wobbling motion Fermi surface particle-rotor model angular momentum geometry

Data-Driven Direct Adaptive Risk-Sensitive Control of Stochastic Systems

在线全文

学校读者我要写书评

暂无评论

Journal of Systems Science & Complexity 2024年第4期37卷 1446-1469页

作者： QIAO Nan LI Tao School of Mathematical Sciences East China Normal UniversityShanghai 200241China Shanghai Key Laboratory of Pure mathematics and Mathematical Practice School of Mathematical SciencesEast China Normal UniversityShanghai 200241China

The authors propose a data-driven direct adaptive control law based on the adaptive dynamic programming(ADP) algorithm for continuous-time stochastic linear systems with partially unknown system dynamics and infinite horizon quadratic risk-sensitive *** authors use online data of the system to iteratively solve the generalized algebraic Riccati equation(GARE) and to learn the optimal control law *** the case with measurable system noises,the authors show that the adaptive control law approximates the optimal control law as time goes *** the case with unmeasurable system noises,the authors use the least-square solution calculated only from the measurable data instead of the real solution of the regression equation to iteratively solve the *** authors also study the influences of the intensity of the system noises,the intensity of the exploration noises,the initial iterative matrix,and the sampling period on the convergence of the ADP ***,the authors present two numerical simulation examples to demonstrate the effectiveness of the proposed algorithms.

关键词： Adaptive dynamic programming direct adaptive control generalized algebraic Riccati equation risk-sensitive control

STABILITY AND CONVERGENCE OF STEPSIZE-DEPENDENT LINEAR MULTISTEP METHODS FOR NONLINEAR DISSIPATIVE EVOLUTION EQUATIONS IN BANACH SPACE

在线全文

学校读者我要写书评

暂无评论

Journal of Computational mathematics 2024年第2期42卷 337-354页

作者： Wansheng Wang department of mathematics Shanghai Normal UniversityShanghai 200234China

Stability and global error bounds are studied for a class of stepsize-dependent linear multistep methods for nonlinear evolution equations governed by ω-dissipative vector fields in Banach *** break through the order barrier p≤1 of unconditionally contractive linear multistep methods for dissipative systems,strongly dissipative systems are *** employing the error growth function of the methods,new contractivity and convergence results of stepsize-dependent linear multistep methods on infinite integration intervals are provided for strictly dissipative systems(ω<0)and strongly dissipative *** applications of the main results to several linear multistep methods,including the trapezoidal rule,are *** theoretical results are also illustrated by a set of numerical experiments.

关键词： Nonlinear evolution equation Linear multistep methods ω-dissipative operators Stability Convergence Banach space

GLOBAL WEAK SOLUTIONS FOR AN ATTRACTION-REPULSION CHEMOTAXIS SYSTEM WITH p-LAPLACIAN DIFFUSION AND LOGISTIC SOURCE

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

Acta Mathematica Scientia 2024年第3期44卷 909-924页

作者：王晓闪王忠谦贾哲 department of mathematics Luoyang Normal UniversityLuoyang471934China School of mathematics Science Jiangsu Second Normal UniversityNanjing210013China School of mathematics and Statistics Linyi UniversityLinyi276005China

This paper is concerned with the following attraction-repulsion chemotaxis system with p-Laplacian diffusion and logistic source:■The system here is under a homogenous Neumann boundary condition in a bounded domainΩ ■ R^(n)(n≥2),with χ,ξ,α,β,γ,δ,k_(1),k_(2)> 0,p> *** addition,the function f is smooth and satisfies that f(s)≤κ-μs~l for all s≥0,with κ ∈ R,μ> 0,l> *** is shown that(ⅰ)if l> max{2k_(1),(2k_(1)n)/(2+n)+1/(p-1)},then system possesses a global bounded weak solution and(ⅱ)if k_(2)> max{2k_(1)-1,(2k_(1)n)/(2+n)+(2-p)/(p-1)} with l> 2,then system possesses a global bounded weak solution.

关键词： global weak solutions attraction-repulsion p-Laplacian logistic source

Semi-derived Ringel-Hall algebras and Hall algebras of odd-periodic relative derived categories

在线全文

学校读者我要写书评

暂无评论

Science china mathematics 2024年第8期67卷 1735-1760页

作者： Ji Lin Liangang Peng department of mathematics and Statistics Fuyang Normal UniversityFuyang 236037China School of mathematics Sichuan UniversityChengdu 610064China

Let t be a positive integer and A be a hereditary abelian category satisfying some finiteness *** define the semi-derived Ringel-Hall algebra of A from the category C_(Z/t)(A)of Z/t-graded complexes and obtain a natural basis of the semi-derived Ringel-Hall ***,we describe the semiderived Ringel-Hall algebra by the generators and defining *** particular,if t is an odd integer,we show an embedding of the derived Hall algebra of the odd-periodic relative derived category in the extended semi-derived Ringel-Hall algebra.

关键词： hereditary abelian categories the categories of Z/t-graded complexes semi-derived Ringel-Hall algebras derived Hall algebras

A REFINEMENT OF THE SCHWARZ-PICK ESTIMATES AND THE CARATHéODORY METRIC IN SEVERAL COMPLEX VARIABLES

在线全文

学校读者我要写书评

暂无评论

Acta Mathematica Scientia 2024年第4期44卷 1337-1346页

作者： Xiaosong LIU Taishun LIU School of mathematics and Statistics Lingnan Normal UniversityZhanjiang 524048China department of mathematics Huzhou UniversityHuzhou 313000China

In this article,we first establish an asymptotically sharp result on the higher order Fréchet derivatives for bounded holomorphic mappings f(x)=f(0)+∞∑s=1Dskf(0)(x^(sk))/(sk)!:B_(X)→B_(Y),where B_X is the unit ball of *** next give a sharp result on the first order Fréchet derivative for bounded holomorphic mappings F(X)=F(0+)∞∑s=KD^(s)f(0)(x^(8)/s!):B_(X)→B_(Y),where B_(X)is the unit ball of *** results that we derive include some results in several complex variables,and extend the classical result in one complex variable to several complex variables.

关键词： refined Schwarz-Pick estimate bounded holomorphic mapping Carathéodory metric first order Fréchet derivative higher order Fréchet derivatives

SUMS OF DUAL TOEPLITZ PRODUCTS ON THE ORTHOGONAL COMPLEMENTS OF FOCK-SOBOLEV SPACES

在线全文

学校读者我要写书评

暂无评论

Acta Mathematica Scientia 2024年第3期44卷 810-822页

作者：陈泳 Young Joo Lee department of mathematics Hangzhou Normal UniversityHangzhou311121China department of mathematics Chonnam National UniversityGwangju61186Korea

We consider dual Toeplitz operators on the orthogonal complements of the FockSobolev spaces of all nonnegative real ***,for symbols in a certain class containing all bounded functions,we study the problem of when an operator which is finite sums of the dual Toeplitz products is compact or ***,for bounded symbols,we construct a symbol map and exhibit a short exact sequence associated with the C^(*)-algebra generated by all dual Toeplitz operators with bounded symbols.

关键词： dual Toeplitz operators Fock-Sobolev spaces symbol map