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Gellerstedt–Moiseev Problem with Data on Parallel Characteristics in the Unbounded Domain for a Mixed Type Equation with Singular Coefficients 带有奇异系数的混合型方程的无界域平行特性数据的盖勒斯特-莫伊耶夫问题
IF 0.7 Q2 MATHEMATICS Pub Date : 2024-07-19 DOI: 10.1134/s199508022460081x
A. K. Urinov, D. M. Mirsaburova

Abstract

In this work, in an unbounded domain, which consists of a half-plane (y>0) and a characteristic triangle for (y<0), a degenerate equation of elliptic-hyperbolic type with singular coefficients is considered for the lower terms of the equation. The correctness of the Gellerstedt–Moiseev ((GM)) problem is studied for data on the part of the boundary and internal characteristics parallel to it. When studying the (GM) problem in the half-plane (y>0), the integral representation of the solution of the Dirichlet problem is used. In the characteristic triangle the Darboux formula, which gives an integral representation of the solution to the modified Cauchy problem with data on the segment ([-1,1]) of the (y=0) axis, is used. To prove the uniqueness of the solution to the problem, a combined method of the extremum principle (for a specially constructed finite domain (D_{R})) and the passing to the limit from the finite domain (D_{R}) to the unbounded domain (D) are used. Using the Dirichlet and Darboux formulas the existence of the solution to the (GM) problem is equivalently reduced to the study of the system of non-standard singular integral equations, which the non-characteristic parts contain non-Fredholm operators with kernels that have isolated first-order singularities. Using the Carleman’s method, i.e., temporarily assuming the non-characteristic parts of these equations as known functions, the regularization of these equations are carried out. From the obtained two relations, one of the unknown function is explicitly expressed through the second one and this makes it possible to reduce this system to the Wiener–Hopf integral equation, which belongs to the class of singular integral equations. It has been proved that the index of this equation is equal to zero. By solving this equation a second kind Fredholm integral equation is obtained. The uniquely solvability of this equation follows from the uniqueness of the solution of the (GM) problem.

AbstractIn this work, in an unbounded domain, which consists of a half-plane (y>0) and a characteristic triangle for (y<0), is considered a degenerate equation of elliptic-hyperbolic type with singular coefficients for the lower terms of the equation.对于边界部分的数据和与之平行的内部特征,研究了 Gellerstedt-Moiseev ((GM))问题的正确性。在研究半平面 (y>0)中的(GM)问题时,使用了迪里夏特问题解的积分表示法。在特征三角形中,使用了达尔布公式,它给出了修正考希问题解的积分表示,其数据在(y=0)轴的([-1,1])段上。为了证明问题解的唯一性,使用了极值原理(对于一个特殊构造的有限域 (D_{R}))和从有限域 (D_{R})到无界域 (D)的极限传递的组合方法。利用狄利克雷公式和达尔布公式,(GM)问题解的存在性等价地简化为非标准奇异积分方程系统的研究,其中非特征部分包含非弗雷德霍姆算子,其核具有孤立的一阶奇异性。利用卡勒曼方法,即暂时假定这些方程的非特征部分为已知函数,对这些方程进行正则化。从得到的两个关系式中,一个未知函数通过第二个关系式明确表达出来,这使得将该系统简化为维纳-霍普夫积分方程成为可能,而后者属于奇异积分方程。事实证明,该方程的指数等于零。通过求解这个方程,可以得到一个第二类弗雷德霍姆积分方程。该方程的唯一可解性源于 (GM) 问题解的唯一性。
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引用次数: 0
Some Infinite Expansions of the Lauricella Functions and Their Application in the Study of Fundamental Solutions of a Singular Elliptic Equation 劳里切拉函数的一些无限展开及其在奇异椭圆方程基本解研究中的应用
IF 0.7 Q2 MATHEMATICS Pub Date : 2024-07-19 DOI: 10.1134/s1995080224600742
T. G. Ergashev, A. Hasanov, T. K. Yuldashev

Abstract

In this article, a new inverse pair of symbolic operators withthe multidimensional analogues is introduced. The properties ofinverse pair of symbolic operators with the multidimensionalanalogues are studied. Formulas for the infinite expansion ofmultiple Lauricella functions are established. The application ofsome expansions in studying the properties of fundamentalsolutions of singular elliptic equations is shown.

摘要 本文介绍了一种新的符号算子逆对与多维类比。研究了符号算子逆对与多维类似的性质。建立了多个劳里切拉函数的无限展开公式。展示了某些展开在研究奇异椭圆方程基本解性质中的应用。
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引用次数: 0
Quality Control of Scientific Plot Collections 科学地块采集的质量控制
IF 0.7 Q2 MATHEMATICS Pub Date : 2024-07-19 DOI: 10.1134/s1995080224600675
N. A. Lavrentiev, A. Z. Fazliev

Abstract

The article considers the problem of quality control of scientific plots on the example of published plots characterizing continuum radiation absorption, properties of weakly bound molecular complexes and absorption cross sections used in atmospheric chemistry. The tasks of systematization of graphical resources are formulated, the functionality of the GrafOnto information system containing graphical resources is described, statistical samples characterizing, in particular, the quality of graphical resources in the collection are presented. The analysis of the quality of citing plots and proximity estimates for pairwise comparisons of all plots in the collection is presented as well as the applied ontology of graphical resources.

摘要 本文以已出版的描述连续辐射吸收、弱结合分子复合物特性和大气化学中使用的吸收截面的图表为例,探讨了科学图表的质量控制问题。文章阐述了图形资源系统化的任务,介绍了包含图形资源的 GrafOnto 信息系统的功能,并提供了统计样本,特别是收集的图形资源的质量特征。此外,还介绍了对引用图质量的分析、对图集中所有图进行成对比较的近似估计以及应用的图形资源本体。
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引用次数: 0
Modeling the Process of Pollutant Spread in the Atmosphere with Account for the Capture of Particles by Vegetation Elements 模拟污染物在大气中的扩散过程并考虑植被要素对微粒的捕获作用
IF 0.7 Q2 MATHEMATICS Pub Date : 2024-07-19 DOI: 10.1134/s1995080224600638
N. Ravshanov, Sh. E. Nazarov, B. Boborakhimov

Abstract

The problems of forecasting the pollutant concentration in the atmosphere by means of mathematical modeling remain one of the most relevant scientific areas. Such a conclusion can be drawn from the analysis of scientific publications related to the problems of mathematical modeling of complex processes of mass transfer in the atmosphere. In this regard, the aim of this study is to develop a mathematical model for the transport and diffusion of emissions of polluting particles of technogenic and natural origin and an effective numerical algorithm for solving the problem with a high-order approximation in time and space variables. A feature of the proposed mathematical apparatus is that, in addition to the main factors, the model takes into account the phenomenon of the capture of aerosol particles by elements of vegetation in the land environment. The solution algorithm is based on the method for splitting the original problem into physical factors: advection, diffusion, and absorption of a substance in the air mass of the atmosphere. Computational experiments were conducted using real meteorological parameters and data on sources of atmospheric pollution. An analysis of the results of numerical calculations showed their good agreement with the data of field measurements and the results obtained by other authors. Thus, the adequacy of the developed mathematical model and the accuracy of the numerical algorithm were sufficiently substantiated. In the course of experiments, the influence of the main factors on the process of transfer and diffusion of particles of harmful substances in the atmosphere was established. Particular attention was paid to the study of how the green cover on the terrain affects the propagation of particle concentration fields; what portion of pollutants can be absorbed by vegetation elements compared to other types of the underlying surface. The practical outcome of the study is the possibility of developing recommendations to support decision-making on maintaining the ecological balance of the environment in industrial regions and protecting it from the possible negative impact of technogenic factors.

摘要 通过数学建模预测大气中污染物浓度的问题仍然是最相关的科学领域之一。通过分析与大气中复杂传质过程的数学建模问题有关的科学出版物,可以得出这样的结论。在这方面,本研究的目的是建立一个技术和自然污染粒子排放传输和扩散的数学模型,以及一个有效的数值算法,用于解决时间和空间变量中的高阶近似问题。所提议的数学装置的一个特点是,除主要因素外,该模型还考虑了陆地环境中植被元素捕获气溶胶颗粒的现象。求解算法基于将原始问题拆分为物理因素的方法:大气气团中物质的平流、扩散和吸收。利用真实的气象参数和大气污染源数据进行了计算实验。对数值计算结果的分析表明,这些结果与实地测量数据和其他作者获得的结果十分吻合。因此,所建立数学模型的适当性和数值算法的准确性得到了充分证实。在实验过程中,确定了主要因素对大气中有害物质颗粒转移和扩散过程的影响。特别注意研究地形上的绿色植被如何影响粒子浓度场的传播;与其他类型的底层表面相比,植被元素能吸收多少污染物。这项研究的实际成果是有可能提出建议,以支持关于维持工业地区环境生态平衡和保护环境免受技术因素可能造成的负面影响的决策。
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引用次数: 0
Optimal Pursuit Differential Game Problem for an Infinite System of Binary Differential Equations 无穷二元微分方程系统的最优追求微分博弈问题
IF 0.7 Q2 MATHEMATICS Pub Date : 2024-07-19 DOI: 10.1134/s1995080224600821
G. I. Ibragimov, X. Sh. Qo’shaqov, A. A. Muxammadjonov

Abstract

We study a differential game problem for an infinite system of binary differential equations. The control functions of pursuer and evader are subjected to integral constraints. The pursuer tries to bring the state of the system to the origin of the Hilbert space (l_{2}) and the aim of the evader is opposite. An equation for the optimal pursuit time is obtained and optimal controls of players are constructed. Also, an auxiliary optimal control problem is solved to prove the main result of the paper.

摘要 我们研究了一个无穷二元微分方程系统的微分博弈问题。追逐者和逃避者的控制函数都受到积分约束。追逐者试图使系统的状态到达希尔伯特空间 (l_{2})的原点,而逃避者的目标则相反。我们得到了最优追逐时间方程,并构建了追逐者的最优控制。此外,还求解了一个辅助最优控制问题,以证明本文的主要结果。
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引用次数: 0
GoKnowGraph: A Multilingual Semantic Search System for Government of Kerala System Documents GoKnowGraph:喀拉拉邦政府系统文件的多语种语义搜索系统
IF 0.7 Q2 MATHEMATICS Pub Date : 2024-07-19 DOI: 10.1134/s1995080224600869
Hashmy Hassan, Sudheep Elayidom, M. R. Irshad, Christophe Chesneau

Abstract

This paper presents the design and construction of GoKnowGraph, a Knowledge Graph (KG) that is customized exclusively for storing and semantically searching for system documents pertaining to the Government of Kerala (GoK). GoKnowGraph empowers the efficient retrieval of relevant government documents in multiple languages, thus augmenting accessibility and information retrieval within this GoK system. Our contributions encompass the development of a meticulously curated ontology, integrating essential information from GoK, and proposing a robust method for constructing and querying the KG. Moreover, our system supports cross-language document search for queries in English and advanced querying options, including attribute-based filters, to ensure precise information retrieval. Comparative assessments against a state-of-the-art system underscore GoKnowGraph’s pronounced superiority in both relevance and accuracy. The meticulous alignment between user queries and the retrieved documents highlights the platform’s capacity to effectively bridge the gap between unstructured data and the facilitation of informed decision-making within the GoK system.

摘要 本文介绍了 GoKnowGraph 的设计和构建,这是一个专门为存储和语义搜索喀拉拉邦政府(GoK)相关系统文件而定制的知识图谱(KG)。GoKnowGraph 能够以多种语言高效检索相关政府文件,从而提高喀拉拉邦政府系统的可访问性和信息检索能力。我们的贡献包括开发了一个精心策划的本体,整合了来自 GoK 的重要信息,并提出了一种构建和查询 GoK 的强大方法。此外,我们的系统还支持跨语言文档搜索(英语查询)和高级查询选项(包括基于属性的过滤器),以确保精确的信息检索。与最先进系统的比较评估结果表明,GoKnowGraph 在相关性和准确性方面都具有明显优势。用户查询与检索到的文件之间的细致吻合突出表明,该平台有能力在非结构化数据与促进 GoK 系统内的知情决策之间架起一座有效的桥梁。
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引用次数: 0
Propagation of Own Waves in a Viscoelastic Cylindrical Panel of Variable Thickness 自身波在厚度可变的粘弹性圆柱形面板中的传播
IF 0.7 Q2 MATHEMATICS Pub Date : 2024-07-19 DOI: 10.1134/s1995080224600663
Ismoil Safarov, Bakhtiyor Nuriddinov, Zhavlon Nuriddinov

Abstract

The paper considers the problem of propagation of natural waves in a viscoelastic cylindrical panel of variable thickness. A mathematical formulation, a solution technique and an algorithm for wave propagation problems in viscoelastic cylindrical panels of variable thickness are formulated. To derive the shell equations, the principle of possible displacements was used (within the framework of the Kirchhoff–Love hypotheses). Using the variational equation and physical equations, a system consisting of eight differential equations is obtained. After some transformations, a spectral boundary value problem on a complex parameter is constructed for a system of eight ordinary differential equations with respect to complex functions of the form. Dispersion relations for the cylindrical panel are obtained, numerical results are obtained and an analysis is made. It is established that in the case of a wedge-shaped cylindrical panel, for each mode, there are limiting propagation velocities with an increase in the wave number that coincide in magnitude with the corresponding velocities of normal waves in a wedge-shaped plate of zero curvature.

摘要 本文研究了自然波在厚度可变的粘弹性圆柱板中的传播问题。针对厚度可变的粘弹性圆柱板中的波传播问题,提出了数学公式、求解技术和算法。为了推导壳方程,使用了可能位移原理(在基尔霍夫-洛夫假设的框架内)。利用变分方程和物理方程,得到了一个由八个微分方程组成的系统。经过一些变换后,为八个常微分方程系统构建了一个关于复参数的谱边界值问题,其形式为复变函数。得到了圆柱形面板的扩散关系、数值结果并进行了分析。结果表明,在楔形圆柱板的情况下,对于每种模式,都存在随着波数增加而增加的极限传播速度,其大小与零曲率楔形板中法线波的相应速度相吻合。
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引用次数: 0
On Linear Two-Point Inverse Problem for a Multidimensional Wave Equation with Semi-Nonlocal Boundary Conditions 关于具有半非局部边界条件的多维波方程的线性两点逆问题
IF 0.7 Q2 MATHEMATICS Pub Date : 2024-07-19 DOI: 10.1134/s1995080224600730
S. Z. Dzhamalov, Sh. Sh. Khudoykulov

Abstract

In this article, we investigated the correctness of a linear two-point inverse problem for a multidimensional wave equation. The unique solvability of a generalized solution to a linear two-point inverse problem for a multidimensional wave equation is proved by methods of a priori estimates, a sequence of approximations, and contracting mappings.

摘要 本文研究了多维波方程线性两点逆问题的正确性。通过先验估计、近似序列和收缩映射等方法证明了多维波方程线性两点逆问题广义解的唯一可解性。
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引用次数: 0
On the Nonlocal Problem for the Equation with the Hilfer Fractional Derivative 论具有希尔费分式衍生物的方程的非局部问题
IF 0.7 Q2 MATHEMATICS Pub Date : 2024-07-19 DOI: 10.1134/s1995080224600729
R. R. Ashurov, Yu. E. Fayziev, N. M. Tukhtaeva

Abstract

In the paper, we study the nonlocal problem for a fractional partial differential equation with the Hilfer derivative. The non-local boundary value problem, (D^{alpha,beta}u(t)+Au(t)=f(t)) ((0<alpha<1), (0leqbetaleq 1) and (0<tleq T)), (I^{delta}u(t)=gamma I^{delta}u(+0)+varphi) ((gamma) is a constant), in an arbitrary separable Hilbert space H with the strongly positive self-adjoint operator (A), is considered. In addition to the forward problem, the article also explores the inverse problem of determining the right-hand side of the equation. Existence and uniqueness theorems are proved to solve the forward and inverse problems.

摘要 本文研究了具有希尔费导数的分数偏微分方程的非局部问题。非局部边界值问题,(D^{alpha,beta}u(t)+Au(t)=f(t)) ((0<alpha<1), (0leqbetaleq 1) and(0<;tleq T)), (I^{delta}u(t)=gamma I^{delta}u(+0)+varphi) (((gamma)是一个常数),在一个任意可分离的希尔伯特空间H中与强正自相加算子(A)一起被考虑。除了正向问题,文章还探讨了确定方程右边的反向问题。证明了求解正向和反向问题的存在性和唯一性定理。
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引用次数: 0
The Future of Cryptocurrency Market Analysis: Social Media Data and User Meta-Data 加密货币市场分析的未来:社交媒体数据和用户元数据
IF 0.7 Q2 MATHEMATICS Pub Date : 2024-07-19 DOI: 10.1134/s1995080224600717
Samyak Jain, Sarthak Johari, Radhakrishnan Delhibabu

Abstract

Cryptocurrency is a form of digital currency using cryptographic techniques in a decentralized system for secure peer-to-peer transactions. It is gaining much popularity over traditional methods of payment because it facilitates very fast, easy, and secure transactions. Social media is a significant influence, but it is also very volatile and subject to a variety of other factors. Thus, with over four billion active users on social media, we need to understand its influence on the crypto market and how it can lead to fluctuations in the values of these cryptocurrencies. In our work, we analyze the influence of activities on Twitter, in particular the sentiments of the tweets posted regarding cryptocurrencies and how they influence their prices. In addition, we also collect metadata related to tweets and users. We try to leverage these features to predict the price of cryptocurrency, for which we use some regression-based models and an LSTM-based model.

摘要 加密货币是一种数字货币,它在分散系统中使用加密技术进行安全的点对点交易。与传统支付方式相比,加密货币因其交易快捷、方便和安全而越来越受欢迎。社交媒体具有重要的影响力,但它也非常不稳定,会受到其他各种因素的影响。因此,面对社交媒体上超过 40 亿的活跃用户,我们需要了解它对加密货币市场的影响,以及它如何导致这些加密货币价值的波动。在我们的工作中,我们分析了 Twitter 上活动的影响,尤其是发布的有关加密货币的推文的情绪,以及它们如何影响其价格。此外,我们还收集了与推文和用户相关的元数据。我们试图利用这些特征来预测加密货币的价格,为此我们使用了一些基于回归的模型和一个基于 LSTM 的模型。
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引用次数: 0
期刊
Lobachevskii Journal of Mathematics
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