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边加权有限图的Weil-Riemann-Roch定理
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作者 曹廷彬 刘洁 《南昌大学学报(理科版)》 CAS 2024年第2期103-107,共5页
Riemann-Roch定理是数学中的一个重要结论,并有了广泛的应用。在有限图和边加权有限图等图中也有对应的Riemann-Roch定理以及应用,但所有这些工作都有一个共同点,那就是它们都聚焦于在除子或和除子线性等价的线丛的情况下,也就是秩为1... Riemann-Roch定理是数学中的一个重要结论,并有了广泛的应用。在有限图和边加权有限图等图中也有对应的Riemann-Roch定理以及应用,但所有这些工作都有一个共同点,那就是它们都聚焦于在除子或和除子线性等价的线丛的情况下,也就是秩为1的情况。为了得到高维秩的情形,可以借助多重除子的术语来描述。本文利用还原群GLn的root datum的概念给出了边加权有限图上主GLn-丛——向量丛的定义,并用多重除子的术语来描述向量丛,进而给出了边加权有限图的Weil-Riemann-Roch定理以及证明,推广了GROSS A.ULIRSCH M.和ZAKHAROV D的结果。 展开更多
关键词 边加权有限图 riemann-Roch定理 向量丛 多重除子
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Proof of Riemann Conjecture Based on Contradiction between Xi-Function and Its Product Expression
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作者 Chuanmiao Chen 《Advances in Pure Mathematics》 2023年第7期463-472,共10页
Riemann proved three results: analytically continue ζ(s) over the whole complex plane s =σ + it with a pole s =1;(Theorem A) functional equation ξ(t) = G(s<sub>0</sub>)ζ (s<sub>0</sub>), s&... Riemann proved three results: analytically continue ζ(s) over the whole complex plane s =σ + it with a pole s =1;(Theorem A) functional equation ξ(t) = G(s<sub>0</sub>)ζ (s<sub>0</sub>), s<sub>0</sub> =1/2 + it and (Theorem B) product expression ξ<sub>1</sub>(t) by all roots of ξ(t). He stated Riemann conjecture (RC): All roots of ξ (t) are real. We find a mistake of Riemann: he used the same notation ξ(t) in two theorems. Theorem B must contain complex roots;it conflicts with RC. Thus theorem B can only be used by contradiction. Our research can be completed on s<sub>0</sub> =1/2 + it. Using all real roots r<sub>k</sub><sub> </sub>and (true) complex roots z<sub>j</sub> = t<sub>j</sub> + ia<sub>j</sub> of ξ (z), define product expressions w(t), w(0) =ξ(0) and Q(t) > 0, Q(0) =1 respectively, so ξ<sub>1</sub>(t) = w(t)Q(t). Define infinite point-set L(ω) = {t : t ≥10 and |ζ(s<sub>0</sub>)| =ω} for small ω > 0. If ξ(t) has complex roots, then ω =ωQ(t) on L(ω). Finally in a large interval of the first module |z<sub>1</sub>|>>1, we can find many points t ∈ L(ω) to make Q(t) . This contraction proves RC. In addition, Riemann hypothesis (RH) ζ for also holds, but it cannot be proved by ζ. 展开更多
关键词 riemann Conjecture Xi-function Functional Equation Product Expression Multiplicative Group CONTRADICTION
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Stability Analysis of a Class of Nonlinear Fractional Differential Systems With Riemann-Liouville Derivative
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作者 Ruoxun Zhang Shiping Yang Shiwen Feng 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第8期1883-1885,共3页
Dear Editor,This letter investigates the stability of n-dimensional nonlinear fractional differential systems with Riemann-Liouville derivative.By using the Mittag-Leffler function,Laplace transform and the Gronwall-B... Dear Editor,This letter investigates the stability of n-dimensional nonlinear fractional differential systems with Riemann-Liouville derivative.By using the Mittag-Leffler function,Laplace transform and the Gronwall-Bellman lemma,one sufficient condition is attained for the asymptotical stability of a class of nonlinear fractional differential systems whose order lies in(0,2).According to this theory,if the nonlinear term satisfies some conditions,then the stability condition for nonlinear fractional differential systems is the same as the ones for corresponding linear systems.Two examples are provided to illustrate the applications of our result. 展开更多
关键词 LIOUVILLE riemann NONLINEAR
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How to Prove Riemann Conjecture by Riemann’s Four Theorems
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作者 Chuanmiao Chen 《Advances in Pure Mathematics》 2024年第8期619-632,共15页
Riemann (1859) had proved four theorems: analytic continuation ζ(s), functional equation ξ(z)=G(s)ζ(s)(s=1/2+iz, z=t−i(σ−1/2)), product expression ξ1(z)and Riemann-Siegel formula Z(z), and proposed Riemann conjec... Riemann (1859) had proved four theorems: analytic continuation ζ(s), functional equation ξ(z)=G(s)ζ(s)(s=1/2+iz, z=t−i(σ−1/2)), product expression ξ1(z)and Riemann-Siegel formula Z(z), and proposed Riemann conjecture (RC): All roots of ξ(z)are real. We have calculated ξand ζ, and found that ξ(z)is alternative oscillation, which intuitively implies RC, and the property of ζ(s)is not good. Therefore Riemann’s direction is correct, but he used the same notation ξ(t)=ξ1(t)to confuse two concepts. So the product expression only can be used in contraction. We find that if ξhas complex roots, then its structure is destroyed, so RC holds. In our proof, using Riemann’s four theorems is sufficient, needn’t cite other results. Hilbert (1900) proposed Riemann hypothesis (RH): The non-trivial roots of ζhave real part 1/2. Of course, RH also holds, but can not be proved directly by ζ(s). 展开更多
关键词 riemann Conjecture ZETA-function Xi-function Functional Equation Product Expression CONTRADICTION
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THE RIEMANN PROBLEM FOR ISENTROPIC COMPRESSIBLE EULER EQUATIONS WITH DISCONTINUOUS FLUX
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作者 孙印正 屈爱芳 袁海荣 《Acta Mathematica Scientia》 SCIE CSCD 2024年第1期37-77,共41页
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 separat... 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 data.The over-compressing condition on the discontinuity x=x(t)is not enough to ensure the uniqueness of the solution.However,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 left-side.As an application,we study a free piston problem with the piston in a tube surrounded initially by uniform pressureless flow and a polytropic gas.In particular,we obtain the existence of a piecewise smooth solution for the motion of the piston between a vacuum and a polytropic gas.This 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. 展开更多
关键词 compressible Euler equations riemann problem Radon measure solution delta shock discontinuous flux wave interactions
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AGGREGATE SPECIAL FUNCTIONS TO APPROXIMATE PERMUTING TRI-HOMOMORPHISMS AND PERMUTING TRI-DERIVATIONS ASSOCIATED WITH A TRI-ADDITIVEψ-FUNCTIONAL INEQUALITY IN BANACH ALGEBRAS
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作者 Safoura Rezaei ADERYANI Azam AHADI +1 位作者 Reza SAADATI Hari M.SRIVASTAVA 《Acta Mathematica Scientia》 SCIE CSCD 2024年第1期311-338,共28页
In this paper,we define a new class of control functions through aggregate special functions.These class of control functions help us to stabilize and approximate a tri-additiveψ-functional inequality to get a better... In this paper,we define a new class of control functions through aggregate special functions.These class of control functions help us to stabilize and approximate a tri-additiveψ-functional inequality to get a better estimation for permuting tri-homomorphisms and permuting tri-derivations in unital C*-algebras and Banach algebras by the vector-valued alternative fixed point theorem. 展开更多
关键词 permuting tri-homomorphism in Banach algebra permuting tri-derivation on C*-algebra fixed point theorem Ulam-Hyers-Rassias stability aggregate special functions tri-additiveψ-functional inequality
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Definite Answer for Riemann Hypothesis Zeta 3/2 Function Provided by New Material Yb2Si2O7 in Quantum Mechanics
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作者 Hung-Te Henry Su Po-Han Lee 《Journal of Modern Physics》 2024年第9期1409-1429,共21页
This paper indicates the problem of the famous Riemann hypothesis (RH), which has been well-verified by a definite answering method using a Bose-Einstein Condensate (BEC) phase. We adopt mathematical induction, mappin... This paper indicates the problem of the famous Riemann hypothesis (RH), which has been well-verified by a definite answering method using a Bose-Einstein Condensate (BEC) phase. We adopt mathematical induction, mappings, and laser photons governed by electromagnetically induced transparency (EIT) to examine the existence of the RH. In considering the well-developed as Riemann zeta function, we find that the existence of RH has a corrected and self-consistent solution. Specifically, there is the only one pole at s = 1 on the complex plane for Riemann’s functions, which generalizes to all non-trivial zeros while s > 1. The essential solution is based on the BEC phases and on the nature of the laser photon(s). This work also incorporates Heisenberg commutators [ x^,p^]=1/2in the field of quantum mechanics. We found that a satisfactory solution for the RH would be incomplete without the formalism of Heisenberg commutators, BEC phases, and EIT effects. Ultimately, we propose the application of qubits in connection with the RH. 展开更多
关键词 BEC Phases EIT Heisenberg Commutators Laser Photons QUBITS riemann Hypothesis
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Machine Learning Approaches for the Solution of the Riemann Problem in Fluid Dynamics:a Case Study
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作者 Vitaly Gyrya Mikhail Shashkov +1 位作者 Alexei Skurikhin Svetlana Tokareva 《Communications on Applied Mathematics and Computation》 EI 2024年第3期1832-1859,共28页
We present our results by using a machine learning(ML)approach for the solution of the Riemann problem for the Euler equations of fluid dynamics.The Riemann problem is an initial-value problem with piecewise-constant ... We present our results by using a machine learning(ML)approach for the solution of the Riemann problem for the Euler equations of fluid dynamics.The Riemann problem is an initial-value problem with piecewise-constant initial data and it represents a mathematical model of the shock tube.The solution of the Riemann problem is the building block for many numerical algorithms in computational fluid dynamics,such as finite-volume or discontinuous Galerkin methods.Therefore,a fast and accurate approximation of the solution of the Riemann problem and construction of the associated numerical fluxes is of crucial importance.The exact solution of the shock tube problem is fully described by the intermediate pressure and mathematically reduces to finding a solution of a nonlinear equation.Prior to delving into the complexities of ML for the Riemann problem,we consider a much simpler formulation,yet very informative,problem of learning roots of quadratic equations based on their coefficients.We compare two approaches:(i)Gaussian process(GP)regressions,and(ii)neural network(NN)approximations.Among these approaches,NNs prove to be more robust and efficient,although GP can be appreciably more accurate(about 30\%).We then use our experience with the quadratic equation to apply the GP and NN approaches to learn the exact solution of the Riemann problem from the initial data or coefficients of the gas equation of state(EOS).We compare GP and NN approximations in both regression and classification analysis and discuss the potential benefits and drawbacks of the ML approach. 展开更多
关键词 Machine learning(ML) Neural network(NN) Gaussian process(GP) riemann problem Numerical fluxes Finite-volume method
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耦合Aw-Rascle-Zhang模型的Riemann解及其稳定性
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作者 潘丽君 吕顺 翁莎莎 《数学物理学报(A辑)》 CSCD 北大核心 2024年第4期885-895,共11页
该文主要研究在单连通道路上具有不同压力项的耦合Aw-Rascle-Zhang(CARZ)交通流模型的黎曼问题,利用特征分析法和相变的相关理论,构造了文献[5]缺失的情形v−+η(ρ−)^(γ)=v+的稳定显式解,并修正了情形v++η(ρ−)γ<v+的黎曼解,完善... 该文主要研究在单连通道路上具有不同压力项的耦合Aw-Rascle-Zhang(CARZ)交通流模型的黎曼问题,利用特征分析法和相变的相关理论,构造了文献[5]缺失的情形v−+η(ρ−)^(γ)=v+的稳定显式解,并修正了情形v++η(ρ−)γ<v+的黎曼解,完善了Herty[5]等人的工作.当CARZ模型中压力项前面的参数μ→η时,证明了该模型黎曼解的唯一性和稳定性. 展开更多
关键词 耦合Aw-Rascle-Zhang交通流模型 黎曼问题 唯一性 稳定性
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协同拟凸函数的Riemann-Liouville分数阶积分不等式
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作者 郑茜 王淑红 《内蒙古民族大学学报(自然科学版)》 2024年第2期46-53,共8页
基于Riemann-Liouville分数阶积分,对协同拟凸函数的Hermite-Hadamard分数阶积分不等式进行了研究。剖析Riemann-Liouville分数阶积分的运算特点,深入探究SAR?KAYA给出的Riemann-Liouville分数阶积分恒等式。在该Riemann-Liouville分数... 基于Riemann-Liouville分数阶积分,对协同拟凸函数的Hermite-Hadamard分数阶积分不等式进行了研究。剖析Riemann-Liouville分数阶积分的运算特点,深入探究SAR?KAYA给出的Riemann-Liouville分数阶积分恒等式。在该Riemann-Liouville分数阶积分恒等式的基础上,利用二元函数的单调性和协同拟凸性,巧妙应用三角不等式和H?lder不等式等经典不等式,建立了若干个协同拟凸函数的Hermite-Hadamard分数阶积分不等式。 展开更多
关键词 协同拟凸函数 HERMITE-HADAMARD不等式 riemann-Liouville分数阶积分
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基于Riemann-Liouville分数阶积分Bernstein-Kantorovich算子的逼近性质
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作者 汪洋 程文韬 +1 位作者 刘玉洁 刘磊 《淮北师范大学学报(自然科学版)》 CAS 2024年第1期27-32,共6页
文章构造一种基于Riemann-Liouville分数阶积分的Bernstein-Kantorovich算子。利用一阶、二阶光滑模、Peetre’-K泛函和Lipschitz型极大函数等工具研究该算子的近似性质。然后利用一阶、二阶和四阶中心矩对该算子建立Vorononskaja型渐... 文章构造一种基于Riemann-Liouville分数阶积分的Bernstein-Kantorovich算子。利用一阶、二阶光滑模、Peetre’-K泛函和Lipschitz型极大函数等工具研究该算子的近似性质。然后利用一阶、二阶和四阶中心矩对该算子建立Vorononskaja型渐进公式。该算子的构建使得在曲线曲面造型方面对于给定的函数将会有更小的近似误差。 展开更多
关键词 BERNSTEIN-KANTOROVICH算子 riemann-Liouville分数阶积分 Peetre’-K泛函 Vorononskaja定理
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一类新型自适应反扩散近似Riemann求解器及其应用 被引量:1
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作者 刘旭亮 范召林 +3 位作者 张树海 李虎 罗勇 孙晓峰 《空气动力学学报》 CSCD 北大核心 2023年第4期52-63,I0001,共13页
对于包含激波、剪切层等复杂结构的流动问题,为了精确模拟剪切层等精细结构,且保证激波计算的稳定性,必须采用低耗散且强鲁棒的数值通量方法。传统的HLL近似Riemann求解器的耗散性较大,Roe、HLLEM和HLLC等近似Riemann求解器在计算某些... 对于包含激波、剪切层等复杂结构的流动问题,为了精确模拟剪切层等精细结构,且保证激波计算的稳定性,必须采用低耗散且强鲁棒的数值通量方法。传统的HLL近似Riemann求解器的耗散性较大,Roe、HLLEM和HLLC等近似Riemann求解器在计算某些含有强激波的物理问题时会出现非物理解,容易导致不稳定。针对这一问题,本文在Riemann求解器中通过合理设计反扩散矩阵,发展了一类具有自适应反扩散的新型Riemann求解器,并将其应用到高阶加权紧致格式,实现了高阶精度求解。通过典型数值算例验证了新型方法的计算精度和稳定性,结果表明本文提出的新型自适应反扩散Riemann求解器克服了传统Riemann求解器的缺陷,既能准确识别剪切层等精细结构,又能保证激波解的稳定性。 展开更多
关键词 近似riemann求解器 自适应反扩散 激波 高阶格式 数值稳定性
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On the Absence of Zeros of Riemann Zeta-Function Out of ℜ(z) = 1/2 被引量:1
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作者 Jorge Julián Sánchez Martínez 《Advances in Pure Mathematics》 2022年第3期178-185,共8页
This work shows, after a brief introduction to Riemann zeta function , the demonstration that all non-trivial zeros of this function lies on the so-called “critical line”,, the one Hardy demonstrated in his famous w... This work shows, after a brief introduction to Riemann zeta function , the demonstration that all non-trivial zeros of this function lies on the so-called “critical line”,, the one Hardy demonstrated in his famous work that infinite countable zeros of the above function can be found on it. Thus, out of this strip, the only remaining zeros of this function are the so-called “trivial ones” . After an analytical introduction reminding the existence of a germ from a generic zero lying in , we show through a Weierstrass-Hadamard representation approach of the above germ that non-trivial zeros out of cannot be found. 展开更多
关键词 riemann Zeta Function ANALYTICITY Weierstrass-Hadamard Product REPRESENTATION
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Riemann-Liouville型分数阶导数的非线性估计 被引量:1
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作者 郭玉祥 马保离 +1 位作者 张庆平 占生宝 《控制理论与应用》 EI CAS CSCD 北大核心 2023年第2期256-266,共11页
本文主要研究任意有界连续信号的Riemann-Liouville分数阶导数估计问题.当分数阶α属于0到1时,首先利用滑模技术提出一种有界连续信号分数阶导数的非线性估计方法;然后将其结果推广至分数阶α∈R+的情况,并给出相应的非线性估计方案.借... 本文主要研究任意有界连续信号的Riemann-Liouville分数阶导数估计问题.当分数阶α属于0到1时,首先利用滑模技术提出一种有界连续信号分数阶导数的非线性估计方法;然后将其结果推广至分数阶α∈R+的情况,并给出相应的非线性估计方案.借助Riemann-Liouville分数阶微积分频率分布模型,本文详细分析讨论了所给分数阶导数非线性估计的收敛性问题,并得到相应闭环系统是渐近稳定的结论.文中所提方法的主要优点是在事先未知给定信号分数阶导数上界的情况下,不仅能自适应地估计其Riemann-Liouville分数阶导数,而且当信号中含有随机噪声和不确定扰动时依然能正常工作.数值仿真实例验证了本文所给估计方法的可行性和有效性. 展开更多
关键词 分数阶微积分 riemann-Liouville 非线性系统 自适应滑模 Gaussian白噪声
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The Symmetry of Riemann <i>ξ</i>-Function
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作者 Chuanmiao Chen 《Advances in Pure Mathematics》 2020年第8期464-470,共7页
To prove RH, studying <span style="white-space:nowrap;"><em>ζ</em> </span>and using pure analysis method likely are two kinds of the incorrect guide. Actually, a unique hope may stud... To prove RH, studying <span style="white-space:nowrap;"><em>ζ</em> </span>and using pure analysis method likely are two kinds of the incorrect guide. Actually, a unique hope may study Riemann function <img src="Edit_b4e53620-7ae2-4a2b-aee0-351c62aef8cd.png" width="250" height="20" alt="" /> by geometric analysis, which has the symmetry: <span style="white-space:nowrap;"><em>v</em></span> = 0 if <span style="white-space:nowrap;"><em>β</em></span> = 0, and <img src="Edit_8c67c5d7-c1d4-4cad-8792-78e4bd172ebd.png" width="150" height="28" alt="" /> Assume that |<em>u</em>| is single peak in each root-interval <img src="Edit_a91df253-2965-4b03-8033-54aba2e23036.png" width="85" height="27" alt="" /> of <em>u</em> for any fixed <span style="white-space:nowrap;"><em>β</em></span> <span style="white-space:nowrap;">∈ (0,1/2]</span>, using the slope <em>u</em><sub><em>t </em></sub>of the single peak, we prove that <em>v</em> has opposite signs at two end-points of <em>I</em><sub><em>j</em></sub>, there surely is an inner point so that <em>v</em> = 0, so {|<em>u</em>|,|<em>v</em>|/<span style="white-space:nowrap;"><em>β</em></span>}form a local peak-valley structure, and have positive lower bound <img src="Edit_04798c0f-8e21-4a3a-ae12-0e28b01ee348.png" width="167" height="22" alt="" />in <em>I</em><sub><em>j</em></sub>. Because each <em>t</em> must lie in some <em style="white-space:normal;">I</em><sub style="white-space:normal;"><em>j</em></sub> , then ||<span style="white-space:nowrap;"><em>ξ</em></span>|| > 0 is valid for any <em>t</em>. In this way, the summation process of <span style="white-space:nowrap;"><em>ξ</em></span> is avoided. We have proved the main theorem: Assume that <em>u</em> (<em>t</em>, <span style="white-space:nowrap;"><em>β</em></span>) is single peak, then RH is valid for any <img src="Edit_ed8521a3-63b1-417f-a3b0-a3c790bae519.png" width="140" height="19" alt="" />. If using the equivalence of Lagarias (1999), the assumption of single peak can be canceled. Therefore our new thinking is that we have found the local peak-valley structure of <span style="white-space:nowrap;"><em>ξ</em></span>, which may be the geometry structure expected by Bombieri (2000), and proposed a basic framework of proving RH by geometric analysis. 展开更多
关键词 riemann ξ-function SYMMETRY Peak-Valley Structure Single Peak RH
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Radon Measure Solutions to Riemann Problems for Isentropic Compressible Euler Equations of Polytropic Gases 被引量:1
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作者 Yunjuan Jin Aifang Qu Hairong Yuan 《Communications on Applied Mathematics and Computation》 2023年第3期1097-1129,共33页
We solve the Riemann problems for isentropic compressible Euler equations of polytropic gases in the class of Radon measures,and the solutions admit the concentration of mass.It is found that under the requirement of ... We solve the Riemann problems for isentropic compressible Euler equations of polytropic gases in the class of Radon measures,and the solutions admit the concentration of mass.It is found that under the requirement of satisfying the over-compressing entropy condition:(i)there is a unique delta shock solution,corresponding to the case that has two strong classical Lax shocks;(ii)for the initial data that the classical Riemann solution contains a shock wave and a rarefaction wave,or two shocks with one being weak,there are infinitely many solutions,each consists of a delta shock and a rarefaction wave;(iii)there are no delta shocks for the case that the classical entropy weak solutions consist only of rarefaction waves.These solutions are self-similar.Furthermore,for the generalized Riemann problem with mass concentrated initially at the discontinuous point of initial data,there always exists a unique delta shock for at least a short time.It could be prolonged to a global solution.Not all the solutions are self-similar due to the initial velocity of the concentrated point-mass(particle).Whether the delta shock solutions constructed satisfy the over-compressing entropy condition is clarified.This is the first result on the construction of singular measure solutions to the compressible Euler system of polytropic gases,that is strictly hyperbolic,and whose characteristics are both genuinely nonlinear.We also discuss possible physical interpretations and applications of these new solutions. 展开更多
关键词 Compressible Euler equations Radon measure solution Delta shock riemann problem NON-UNIQUENESS
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指数函数曲线上的矩阵值Riemann边值问题
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作者 刘艳楠 刘华 《理论数学》 2023年第2期212-218,共7页
本文讨论的是指数函数曲线上的矩阵值Riemann边值问题,我们主要是对一类特殊的下三角矩阵值Riemann边值问题进行求解。首先使用双线性形式给出指数函数曲线上的伪正交多项式;其次给出特殊的下三角矩阵值边值问题并转化为边值问题;最后使... 本文讨论的是指数函数曲线上的矩阵值Riemann边值问题,我们主要是对一类特殊的下三角矩阵值Riemann边值问题进行求解。首先使用双线性形式给出指数函数曲线上的伪正交多项式;其次给出特殊的下三角矩阵值边值问题并转化为边值问题;最后使用Liouville定理和伪正交多项式给出矩阵值Riemann边值问题的求解。 展开更多
关键词 指数函数曲线 CAUCHY型积分 矩阵值riemann边值问题
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关于Riemann-Lebesgue引理的一个推广
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作者 王洋洋 林珑 《河北师范大学学报(自然科学版)》 CAS 2023年第5期454-459,共6页
通过“把Riemann-Lebesgue引理看做是在一个周期上可积的周期函数的一种性质”的这个角度,提出了亚周期函数的概念,并得到有界亚周期函数的刻画.
关键词 riemann-Lebesgue引理 亚周期函数 泛函
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一类Riemann-Liouville分数阶时滞随机发展方程的Ulam-Hyers稳定性 被引量:1
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作者 白玉洁 杨和 《吉林大学学报(理学版)》 CAS 北大核心 2023年第3期483-489,共7页
用不动点定理研究Hilbert空间中一类含α∈(0,1)阶Riemann-Liouville分数阶导数的时滞随机发展方程温和解的存在唯一性,并证明该解的Ulam-Hyers稳定性.最后举例说明所得结论的适用性.
关键词 riemann-Liouville分数阶导数 随机发展方程 时滞 Ulam-Hyers稳定性
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Comparative study of the adsorption performance of NH_(2)-functionalized metal organic frameworks with activated carbon composites for the treatment of phenolic wastewaters
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作者 Bolong Jiang Shunjie Shi +3 位作者 Yanyan Cui Jiayou Li Nan Jiang Yanguang Chen 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2023年第11期130-139,共10页
To better understand the role of the-NH_(2)group in adsorption process of phenolic wastewaters,NH_(2)-functionalized MIL-53(Al)composites with activated carbon(NH_(2)-M(Al)@(B)AC)were prepared.The results showed that ... To better understand the role of the-NH_(2)group in adsorption process of phenolic wastewaters,NH_(2)-functionalized MIL-53(Al)composites with activated carbon(NH_(2)-M(Al)@(B)AC)were prepared.The results showed that the-NH_(2)group could increase the mesopore volume for composites,which promotes mass transfer and full utilization of active sites,because hierarchical mesopore structure makes the adsorbent easier to enter the internal adsorption sites.Furthermore,the introduction of the-NH_(2)group can improve the adsorption capacity,decrease the activation energy,and enhance the interaction between the adsorbent and p-nitrophenol,demonstrating that the-NH_(2)group plays a crucial role in the adsorption of p-nitrophenol.The density functional theory calculation results show that the H-bond interaction between the-NH_(2)group in the adsorbent and the-NO_(2)in the p-nitrophenol(adsorption energy of -35.5 kJ·mol^(-1)),and base-acid interaction between the primary-NH_(2)group in the adsorbent and the acidic-OH group in the p-nitrophenol(adsorption energy of -27.3 kJ·mol^(-1))are predominant mechanisms for adsorption in terms of the NH_(2)-functionalized adsorbent.Both NH_(2)-functionalized M(Al)@AC and M(Al)@BAC composites exhibited higher p-nitrophenol adsorption capacity than corresponding nonfunctionalized composites.Among the composites,the NH_(2)-M(Al)@BAC had the highest p-nitrophenol adsorption capacity of 474 mg·g^(-1). 展开更多
关键词 NH_(2)-functionalized adsorbent Phenolic wastewaters ADSORPTION Mechanism Density functional theory
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