Journal of Mathematical Chemistry最新文献_第9页

Graph realization of sets of integers 整数集合的图形实现

IF 1.7 3区化学

Journal of Mathematical Chemistry Pub Date : 2024-06-24 DOI: 10.1007/s10910-024-01642-4

Piotr Wawrzyniak, Piotr Formanowicz

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引用次数: 0

A parameter-uniform hybrid scheme designed for multi-point boundary value problems that are perturbed 为受扰动的多点边界值问题设计的参数统一混合方案

IF 1.7 3区化学

Journal of Mathematical Chemistry Pub Date : 2024-06-24 DOI: 10.1007/s10910-024-01639-z

Parvin Kumari, Devendra Kumar, Jesus Vigo-Aguiar

{"title":"A parameter-uniform hybrid scheme designed for multi-point boundary value problems that are perturbed","authors":"Parvin Kumari, Devendra Kumar, Jesus Vigo-Aguiar","doi":"10.1007/s10910-024-01639-z","DOIUrl":"10.1007/s10910-024-01639-z","url":null,"abstract":"<div><p>The numerical solution of a class of second-order singularly perturbed three-point boundary value problems (BVPs) in 1D is achieved using a uniformly convergent, stable, and efficient difference method on a piecewise-uniform mesh. The presence of a boundary layer(s) on one (or both) of the interval’s endpoints is caused by the presence of the tiny parameter in the highest order derivative. As the perturbation parameter approaches 0, traditional numerical techniques on the uniform mesh become insufficient, resulting in poor accuracy and large blows without the use of an excessive number of points. Specially customised techniques, such as fitted operator methods or methods linked to adapted or fitted meshes that solve essential characteristics such as boundary and/or inner layers, are necessary to overcome this drawback. We developed a fitted-mesh technique in this paper that works for all perturbation parameter values. The monotone hybrid technique, which includes midway upwinding in the outer area and centre differencing in the layer region on a fitted-mesh condensing in the border layer region, is the basis for our difference scheme. In a discrete <span>(L^infty )</span> norm, uniform error estimates are constructed, and the technique is demonstrated to be parameter-uniform convergent of order two (up to a logarithmic factor). To show the effectiveness of the recommended technique and to corroborate the theoretical findings, a numerical example is presented. In practise, the convergence obtained matches the theoretical expectations.</p></div>","PeriodicalId":648,"journal":{"name":"Journal of Mathematical Chemistry","volume":"62 8","pages":"1982 - 2006"},"PeriodicalIF":1.7,"publicationDate":"2024-06-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141521896","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Linearized Boltzmann collision operator for a mixture of monatomic and polyatomic chemically reacting species 单原子和多原子化学反应混合物的线性化玻尔兹曼碰撞算子

IF 1.7 3区化学

Journal of Mathematical Chemistry Pub Date : 2024-06-19 DOI: 10.1007/s10910-024-01633-5

Niclas Bernhoff

{"title":"Linearized Boltzmann collision operator for a mixture of monatomic and polyatomic chemically reacting species","authors":"Niclas Bernhoff","doi":"10.1007/s10910-024-01633-5","DOIUrl":"10.1007/s10910-024-01633-5","url":null,"abstract":"<div><p>At higher altitudes near space shuttles moving at hypersonic speed the air is excited to high temperatures. Then not only mechanical collisions are affecting the gas flow, but also chemical reactions have an impact on such hypersonic flows. In this work we insert chemical reactions, in form of dissociations and associations, in a model for a mixture of mono- and polyatomic (non-reacting) species. More general chemical reactions, e.g., bimolecular ones, can be obtained by instant combinations of the considered reactions. Polyatomicity is here modelled by a continuous internal energy variable and the evolution of the gas is described by a Boltzmann equation. In the Chapman-Enskog process—and related half-space problems—the linearized Boltzmann collision operator plays a central role. Here we extend some important properties of the linearized operator to the considered model with chemical reactions. A compactness result, that the linearized operator can be decomposed into a sum of a positive multiplication operator—the collision frequency—and a compact integral operator, is obtained. The terms of the integral operator are shown to be (at least) uniform limits of Hilbert-Schmidt integral operators and, thereby, compact operators. Self-adjointness of the linearized operator follows as a direct consequence. Also, bounds on—including coercivity of—the collision frequency is obtained for hard sphere, as well as hard potentials with cutoff, like models. As consequence, Fredholmness as well as the domain of the linearized operator are obtained.</p></div>","PeriodicalId":648,"journal":{"name":"Journal of Mathematical Chemistry","volume":"62 8","pages":"1935 - 1964"},"PeriodicalIF":1.7,"publicationDate":"2024-06-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s10910-024-01633-5.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141506925","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Numerical investigation of two fractional operators for time fractional delay differential equation 时间分数延迟微分方程两个分数算子的数值研究

IF 1.7 3区化学

Journal of Mathematical Chemistry Pub Date : 2024-06-19 DOI: 10.1007/s10910-024-01637-1

Reetika Chawla, Devendra Kumar, Dumitru Baleanu

引用次数: 0

Dynamical behavior of a classical stochastic delayed chemostat model 经典随机延迟恒温模型的动力学行为

IF 1.7 3区化学

Journal of Mathematical Chemistry Pub Date : 2024-06-14 DOI: 10.1007/s10910-024-01632-6

Xiaofeng Zhang, Shulin Sun

引用次数: 0

Analysis of an almost second-order parameter-robust numerical technique for a weakly coupled system of singularly perturbed convection-diffusion equations 奇异扰动对流扩散方程弱耦合系统的近二阶参数稳健数值技术分析

IF 1.7 3区化学

Journal of Mathematical Chemistry Pub Date : 2024-06-12 DOI: 10.1007/s10910-024-01634-4

S. Chandra Sekhara Rao, Varsha Srivastava

引用次数: 0

An effective multistep fourteenth-order phase-fitting approach to solving chemistry problems 解决化学问题的有效多步十四阶相位拟合方法

IF 1.7 3区化学

Journal of Mathematical Chemistry Pub Date : 2024-06-12 DOI: 10.1007/s10910-024-01628-2

Hui Huang, Cheng Liu, Chia-Liang Lin, T. E. Simos

引用次数: 0

Efficient computational method for singularly perturbed Burger-Huxley equations 奇异扰动布尔格-赫胥黎方程的高效计算方法

IF 1.7 3区化学

Journal of Mathematical Chemistry Pub Date : 2024-06-10 DOI: 10.1007/s10910-024-01627-3

Masho Jima Kabeto, Tesfaye Aga Bullo, Habtamu Garoma Debela, Gemadi Roba Kusi, Sisay Dibaba Robi

引用次数: 0

An efficient numerical algorithm for solving linear systems with cyclic tridiagonal coefficient matrices 解循环三对角系数矩阵线性系统的高效数值算法

IF 1.7 3区化学

Journal of Mathematical Chemistry Pub Date : 2024-06-08 DOI: 10.1007/s10910-024-01631-7

Ji-Teng Jia, Fu-Rong Wang, Rong Xie, Yi-Fan Wang

引用次数: 0

The use of a multistep, cost-efficient fourteenth-order phase-fitting method to chemistry problems 在化学问题中使用多步骤、经济高效的十四阶相位拟合方法

IF 1.7 3区化学

Journal of Mathematical Chemistry Pub Date : 2024-06-07 DOI: 10.1007/s10910-024-01623-7

Rong Xu, Bin Sun, Chia-Liang Lin, T. E. Simos

引用次数: 0