首页 > 最新文献

AppliedMath最新文献

英文 中文
New Bivariate Copulas via Lomax Distribution Generated Distortions 通过洛马克斯分布产生的扭曲建立新的二元 Copulas
Pub Date : 2024-05-17 DOI: 10.3390/appliedmath4020035
Fadal Abdullah-A Aldhufairi, J. Sepanski
We develop a framework for creating distortion functions that are used to construct new bivariate copulas. It is achieved by transforming non-negative random variables with Lomax-related distributions. In this paper, we apply the distortions to the base copulas of independence, Clayton, Frank, and Gumbel copulas. The properties of the tail dependence coefficient, tail order, and concordance ordering are explored for the new families of distorted copulas. We conducted an empirical study using the daily net returns of Amazon and Google stocks from January 2014 to December 2023. We compared the popular Clayton, Gumbel, Frank, and Gaussian copula models to their corresponding distorted copula models induced by the unit-Lomax and unit-inverse Pareto distortions. The new families of distortion copulas are equipped with additional parameters inherent in the distortion function, providing more flexibility, and are demonstrated to perform better than the base copulas. After analyzing the data, we have found that the joint extremes of Amazon and Google stocks are more likely for high daily net returns than for low daily net returns.
我们开发了一个创建扭曲函数的框架,用于构建新的双变量协方差。它是通过转换具有洛马克斯相关分布的非负随机变量来实现的。在本文中,我们将扭曲函数应用于独立性基础协方差、克莱顿协方差、弗兰克协方差和甘贝尔协方差。我们探讨了新的扭曲协方差系列的尾部依赖系数、尾部顺序和协方差排序的特性。我们使用亚马逊和谷歌股票从 2014 年 1 月到 2023 年 12 月的每日净收益率进行了实证研究。我们将流行的克莱顿、甘贝尔、弗兰克和高斯共线模型与由单位-洛马克斯和单位-反帕累托扭曲引起的相应扭曲共线模型进行了比较。新的扭曲 copulas 系列配备了扭曲函数中固有的附加参数,提供了更大的灵活性,并证明其性能优于基础 copulas。经过数据分析,我们发现亚马逊和谷歌股票的联合极端值更有可能出现在高日净回报率中,而不是低日净回报率中。
{"title":"New Bivariate Copulas via Lomax Distribution Generated Distortions","authors":"Fadal Abdullah-A Aldhufairi, J. Sepanski","doi":"10.3390/appliedmath4020035","DOIUrl":"https://doi.org/10.3390/appliedmath4020035","url":null,"abstract":"We develop a framework for creating distortion functions that are used to construct new bivariate copulas. It is achieved by transforming non-negative random variables with Lomax-related distributions. In this paper, we apply the distortions to the base copulas of independence, Clayton, Frank, and Gumbel copulas. The properties of the tail dependence coefficient, tail order, and concordance ordering are explored for the new families of distorted copulas. We conducted an empirical study using the daily net returns of Amazon and Google stocks from January 2014 to December 2023. We compared the popular Clayton, Gumbel, Frank, and Gaussian copula models to their corresponding distorted copula models induced by the unit-Lomax and unit-inverse Pareto distortions. The new families of distortion copulas are equipped with additional parameters inherent in the distortion function, providing more flexibility, and are demonstrated to perform better than the base copulas. After analyzing the data, we have found that the joint extremes of Amazon and Google stocks are more likely for high daily net returns than for low daily net returns.","PeriodicalId":503400,"journal":{"name":"AppliedMath","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-05-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140965972","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Three-Body 3D-Kepler Electromagnetic Problem—Existence of Periodic Solutions 三体 3D 开普勒电磁问题--周期解的存在性
Pub Date : 2024-05-16 DOI: 10.3390/appliedmath4020034
V. Angelov
The main purpose of the present paper is to prove the existence of periodic solutions of the three-body problem in the 3D Kepler formulation. We have solved the same problem in the case when the three particles are considered in an external inertial system. We start with the three-body equations of motion, which are a subset of the equations of motion (previously derived by us) for any number of bodies. In the Minkowski space, there are 12 equations of motion. It is proved that three of them are consequences of the other nine, so their number becomes nine, as much as the unknown trajectories are. The Kepler formulation assumes that one particle (the nucleus) is placed at the coordinate origin. The motion of the other two particles is described by a neutral system with respect to the unknown velocities. The state-dependent delays arise as a consequence of the finite vacuum speed of light. We obtain the equations of motion in spherical coordinates and split them into two groups. In the first group all arguments of the unknown functions are delays. We take their solutions as initial functions. Then, the equations of motion for the remaining two particles must be solved to the right of the initial point. To prove the existence–uniqueness of a periodic solution, we choose a space consisting of periodic infinitely smooth functions satisfying some supplementary conditions. Then, we use a suitable operator which acts on these spaces and whose fixed points are periodic solutions. We apply the fixed point theorem for the operators acting on the spaces of periodic functions. In this manner, we show the stability of the He atom in the frame of classical electrodynamics. In a previous paper of ours, we proved the existence of spin functions for plane motion. Thus, we confirm the Bohr and Sommerfeld’s hypothesis for the He atom.
本文的主要目的是证明三维开普勒公式中三体问题周期解的存在性。我们已经解决了在外部惯性系中考虑三个粒子时的相同问题。我们从三体运动方程入手,三体运动方程是(我们之前推导的)任意数目物体运动方程的子集。在闵科夫斯基空间,有 12 个运动方程。事实证明,其中三个是其他九个的结果,因此它们的数量变成了九个,就像未知轨迹一样多。开普勒公式假定一个粒子(原子核)位于坐标原点。其他两个粒子的运动由一个中性系统来描述,与未知速度有关。由于有限的真空光速,产生了与状态相关的延迟。我们得到了球面坐标下的运动方程,并将其分为两组。在第一组中,所有未知函数的参数都是延迟。我们将它们的解作为初始函数。然后,其余两个粒子的运动方程必须在初始点右侧求解。为了证明周期解的存在性和唯一性,我们选择一个由满足某些补充条件的周期性无限平稳函数组成的空间。然后,我们使用一个合适的算子,该算子作用于这些空间,其固定点为周期解。我们应用作用于周期函数空间的算子的定点定理。通过这种方法,我们证明了 He 原子在经典电动力学框架下的稳定性。在我们之前的一篇论文中,我们证明了平面运动自旋函数的存在。因此,我们证实了玻尔和萨默菲尔德关于氦原子的假设。
{"title":"Three-Body 3D-Kepler Electromagnetic Problem—Existence of Periodic Solutions","authors":"V. Angelov","doi":"10.3390/appliedmath4020034","DOIUrl":"https://doi.org/10.3390/appliedmath4020034","url":null,"abstract":"The main purpose of the present paper is to prove the existence of periodic solutions of the three-body problem in the 3D Kepler formulation. We have solved the same problem in the case when the three particles are considered in an external inertial system. We start with the three-body equations of motion, which are a subset of the equations of motion (previously derived by us) for any number of bodies. In the Minkowski space, there are 12 equations of motion. It is proved that three of them are consequences of the other nine, so their number becomes nine, as much as the unknown trajectories are. The Kepler formulation assumes that one particle (the nucleus) is placed at the coordinate origin. The motion of the other two particles is described by a neutral system with respect to the unknown velocities. The state-dependent delays arise as a consequence of the finite vacuum speed of light. We obtain the equations of motion in spherical coordinates and split them into two groups. In the first group all arguments of the unknown functions are delays. We take their solutions as initial functions. Then, the equations of motion for the remaining two particles must be solved to the right of the initial point. To prove the existence–uniqueness of a periodic solution, we choose a space consisting of periodic infinitely smooth functions satisfying some supplementary conditions. Then, we use a suitable operator which acts on these spaces and whose fixed points are periodic solutions. We apply the fixed point theorem for the operators acting on the spaces of periodic functions. In this manner, we show the stability of the He atom in the frame of classical electrodynamics. In a previous paper of ours, we proved the existence of spin functions for plane motion. Thus, we confirm the Bohr and Sommerfeld’s hypothesis for the He atom.","PeriodicalId":503400,"journal":{"name":"AppliedMath","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-05-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140969217","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
A Study of Singular Similarity Solutions to Laplace’s Equation with Dirichlet Boundary Conditions 带 Dirichlet 边界条件的拉普拉斯方程奇异相似解的研究
Pub Date : 2024-05-06 DOI: 10.3390/appliedmath4020033
Chao-Kang Feng, Jyh-Haw Tang
The infinite series solution to the boundary-value problems of Laplace’s equation with discontinuous Dirichlet boundary conditions was found by using the basic method of separation of variables. The merit of this paper is that the closed-form solution, or the singular similarity solution in the semi-infinite strip domain and the first-quadrant domain, can be generated from the basic infinite series solution in the rectangular domain. Moreover, based on the superposition principle, the infinite series solution in the rectangular domain can be related to the singular similarity solution in the semi-infinite strip domain. It is proven that the analytical source-type singular behavior in the infinite series solution near certain singular points in the rectangular domain can be revealed from the singular similarity solution in the semi-infinite strip domain. By extending the boundary of the rectangular domain, the infinite series solution to Laplace’s equation in the first-quadrant domain can be derived to obtain the analytical singular similarity solution in a direct and much easier way than by using the methods of Fourier transform, images, and conformal mapping.
利用基本的变量分离法,找到了具有不连续 Dirichlet 边界条件的拉普拉斯方程边界值问题的无穷级数解。本文的优点在于可以从矩形域中的基本无穷级数解生成闭式解或半无限条带域和第一象限域中的奇异相似解。此外,根据叠加原理,矩形域中的无穷级数解可以与半无限条带域中的奇异相似解相关联。研究证明,矩形域中某些奇异点附近的无穷级数解中的分析源型奇异行为可以从半无限条形域中的奇异相似解中得到揭示。通过扩展矩形域的边界,可以推导出拉普拉斯方程在第一象限域中的无穷级数解,从而直接获得解析奇异相似解,比使用傅立叶变换、图像和保角映射等方法简单得多。
{"title":"A Study of Singular Similarity Solutions to Laplace’s Equation with Dirichlet Boundary Conditions","authors":"Chao-Kang Feng, Jyh-Haw Tang","doi":"10.3390/appliedmath4020033","DOIUrl":"https://doi.org/10.3390/appliedmath4020033","url":null,"abstract":"The infinite series solution to the boundary-value problems of Laplace’s equation with discontinuous Dirichlet boundary conditions was found by using the basic method of separation of variables. The merit of this paper is that the closed-form solution, or the singular similarity solution in the semi-infinite strip domain and the first-quadrant domain, can be generated from the basic infinite series solution in the rectangular domain. Moreover, based on the superposition principle, the infinite series solution in the rectangular domain can be related to the singular similarity solution in the semi-infinite strip domain. It is proven that the analytical source-type singular behavior in the infinite series solution near certain singular points in the rectangular domain can be revealed from the singular similarity solution in the semi-infinite strip domain. By extending the boundary of the rectangular domain, the infinite series solution to Laplace’s equation in the first-quadrant domain can be derived to obtain the analytical singular similarity solution in a direct and much easier way than by using the methods of Fourier transform, images, and conformal mapping.","PeriodicalId":503400,"journal":{"name":"AppliedMath","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-05-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141010026","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
A G-Modified Helmholtz Equation with New Expansions for the Earth’s Disturbing Gravitational Potential, Its Functionals and the Study of Isogravitational Surfaces 带有地球扰动引力势新展开的 G 修正亥姆霍兹方程、其函数和等重力面研究
Pub Date : 2024-05-04 DOI: 10.3390/appliedmath4020032
G. Manoussakis
The G-modified Helmholtz equation is a partial differential equation that enables us to express gravity intensity g as a series of spherical harmonics having radial distance r in irrational powers. The Laplace equation in three-dimensional space (in Cartesian coordinates, is the sum of the second-order partial derivatives of the unknown quantity equal to zero) is used to express the Earth’s gravity potential (disturbing and normal potential) in order to represent other useful quantities—which are also known as functionals of the disturbing potential—such as gravity disturbance, gravity anomaly, and geoid undulation as a series of spherical harmonics. We demonstrate that by using the G-modified Helmholtz equation, not only gravity intensity but also disturbing potential and its functionals can be expressed as a series of spherical harmonics. Having gravity intensity represented as a series of spherical harmonics allows us to create new Global Gravity Models. Furthermore, a more detailed examination of the Earth’s isogravitational surfaces is conducted. Finally, we tabulate our results, which makes it clear that new Global Gravity Models for gravity intensity g will be very useful for many geophysical and geodetic applications.
G 修正亥姆霍兹方程是一个偏微分方程,它使我们能够将重力强度 g 表示为一系列径向距离为 r 的无理幂球面谐波。三维空间中的拉普拉斯方程(在直角坐标中,未知量的二阶偏导数之和等于零)用于表示地球重力势能(扰动势能和法向势能),以便将其他有用的量--也称为扰动势能的函数--如重力扰动、重力异常和大地水准面起伏表示为一系列球面谐波。我们证明,通过使用 G 修正亥姆霍兹方程,不仅重力强度,而且扰动势及其函数都可以用一系列球面谐波来表示。将重力强度表示为一系列球面谐波使我们能够创建新的全球重力模型。此外,我们还对地球等重力面进行了更详细的研究。最后,我们以表格形式列出了我们的研究结果,这些结果清楚地表明,重力强度 g 的新全球重力模型将对许多地球物理和大地测量应用非常有用。
{"title":"A G-Modified Helmholtz Equation with New Expansions for the Earth’s Disturbing Gravitational Potential, Its Functionals and the Study of Isogravitational Surfaces","authors":"G. Manoussakis","doi":"10.3390/appliedmath4020032","DOIUrl":"https://doi.org/10.3390/appliedmath4020032","url":null,"abstract":"The G-modified Helmholtz equation is a partial differential equation that enables us to express gravity intensity g as a series of spherical harmonics having radial distance r in irrational powers. The Laplace equation in three-dimensional space (in Cartesian coordinates, is the sum of the second-order partial derivatives of the unknown quantity equal to zero) is used to express the Earth’s gravity potential (disturbing and normal potential) in order to represent other useful quantities—which are also known as functionals of the disturbing potential—such as gravity disturbance, gravity anomaly, and geoid undulation as a series of spherical harmonics. We demonstrate that by using the G-modified Helmholtz equation, not only gravity intensity but also disturbing potential and its functionals can be expressed as a series of spherical harmonics. Having gravity intensity represented as a series of spherical harmonics allows us to create new Global Gravity Models. Furthermore, a more detailed examination of the Earth’s isogravitational surfaces is conducted. Finally, we tabulate our results, which makes it clear that new Global Gravity Models for gravity intensity g will be very useful for many geophysical and geodetic applications.","PeriodicalId":503400,"journal":{"name":"AppliedMath","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-05-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141013310","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Quantum Mixtures and Information Loss in Many-Body Systems 多体系统中的量子混合物与信息丢失
Pub Date : 2024-05-02 DOI: 10.3390/appliedmath4020031
D. Monteoliva, A. Plastino, A. Plastino
In our study, we investigate the phenomenon of information loss, as measured by the Kullback–Leibler divergence, in a many-fermion system, such as the Lipkin model. Information loss is introduced as the number N of particles increases, particularly when the system is in a mixed state. We find that there is a significant loss of information under these conditions. However, we observe that this loss nearly disappears when the system is in a pure state. Our analysis employs tools from information theory to quantify and understand these effects.
在我们的研究中,我们探讨了多费米子系统(如利普金模型)中的信息损失现象,这种损失是通过库尔贝-莱布勒发散来衡量的。随着粒子数 N 的增加,特别是当系统处于混合状态时,会出现信息丢失现象。我们发现,在这些条件下会出现明显的信息损失。然而,我们观察到,当系统处于纯净状态时,这种损失几乎消失。我们的分析运用了信息论的工具来量化和理解这些影响。
{"title":"Quantum Mixtures and Information Loss in Many-Body Systems","authors":"D. Monteoliva, A. Plastino, A. Plastino","doi":"10.3390/appliedmath4020031","DOIUrl":"https://doi.org/10.3390/appliedmath4020031","url":null,"abstract":"In our study, we investigate the phenomenon of information loss, as measured by the Kullback–Leibler divergence, in a many-fermion system, such as the Lipkin model. Information loss is introduced as the number N of particles increases, particularly when the system is in a mixed state. We find that there is a significant loss of information under these conditions. However, we observe that this loss nearly disappears when the system is in a pure state. Our analysis employs tools from information theory to quantify and understand these effects.","PeriodicalId":503400,"journal":{"name":"AppliedMath","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-05-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141020819","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Approximating a Function with a Jump Discontinuity—The High-Noise Case 用跳跃不连续逼近函数--高噪声情况
Pub Date : 2024-05-02 DOI: 10.3390/appliedmath4020030
Qusay Muzaffar, David Levin, Michael Werman
This paper presents a novel deep-learning network designed to detect intervals of jump discontinuities in single-variable piecewise smooth functions from their noisy samples. Enhancing the accuracy of jump discontinuity estimations can be used to find a more precise overall approximation of the function, as traditional approximation methods often produce significant errors near discontinuities. Detecting intervals of discontinuities is relatively straightforward when working with exact function data, as finite differences in the data can serve as indicators of smoothness. However, these smoothness indicators become unreliable when dealing with highly noisy data. In this paper, we propose a deep-learning network to pinpoint the location of a jump discontinuity even in the presence of substantial noise.
本文介绍了一种新型深度学习网络,旨在从噪声样本中检测单变量片断平稳函数中的跳跃不连续区间。提高跳跃不连续性估计的准确性可用于找到函数更精确的整体近似值,因为传统的近似方法往往会在不连续性附近产生显著误差。在处理精确函数数据时,检测不连续区间相对简单,因为数据中的有限差分可以作为平稳性指标。然而,在处理高噪声数据时,这些平稳性指标就变得不可靠了。在本文中,我们提出了一种深度学习网络,即使在存在大量噪声的情况下,也能精确定位跳跃不连续性的位置。
{"title":"Approximating a Function with a Jump Discontinuity—The High-Noise Case","authors":"Qusay Muzaffar, David Levin, Michael Werman","doi":"10.3390/appliedmath4020030","DOIUrl":"https://doi.org/10.3390/appliedmath4020030","url":null,"abstract":"This paper presents a novel deep-learning network designed to detect intervals of jump discontinuities in single-variable piecewise smooth functions from their noisy samples. Enhancing the accuracy of jump discontinuity estimations can be used to find a more precise overall approximation of the function, as traditional approximation methods often produce significant errors near discontinuities. Detecting intervals of discontinuities is relatively straightforward when working with exact function data, as finite differences in the data can serve as indicators of smoothness. However, these smoothness indicators become unreliable when dealing with highly noisy data. In this paper, we propose a deep-learning network to pinpoint the location of a jump discontinuity even in the presence of substantial noise.","PeriodicalId":503400,"journal":{"name":"AppliedMath","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-05-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141023085","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Minimal Terracini Loci in a Plane and Their Generalizations 平面上的最小特雷西尼线性及其泛化
Pub Date : 2024-04-17 DOI: 10.3390/appliedmath4020028
E. Ballico
We study properties of the minimal Terracini loci, i.e., families of certain zero-dimensional schemes, in a projective plane. Among the new results here are: a maximality theorem and the existence of arbitrarily large gaps or non-gaps for the integers x for which the minimal Terracini locus in degree d is non-empty. We study similar theorems for the critical schemes of the minimal Terracini sets. This part is framed in a more general framework.
我们研究的是投影平面中的最小特拉奇尼位置(即某些零维方案的族)的性质。这里的新成果包括:最大化定理和存在任意大的间隙或非间隙的整数 x,对于这些整数 x,度数为 d 的最小特雷西尼位置是非空的。我们还研究了极小特雷西尼集合临界方案的类似定理。这部分内容是在一个更一般的框架下进行的。
{"title":"Minimal Terracini Loci in a Plane and Their Generalizations","authors":"E. Ballico","doi":"10.3390/appliedmath4020028","DOIUrl":"https://doi.org/10.3390/appliedmath4020028","url":null,"abstract":"We study properties of the minimal Terracini loci, i.e., families of certain zero-dimensional schemes, in a projective plane. Among the new results here are: a maximality theorem and the existence of arbitrarily large gaps or non-gaps for the integers x for which the minimal Terracini locus in degree d is non-empty. We study similar theorems for the critical schemes of the minimal Terracini sets. This part is framed in a more general framework.","PeriodicalId":503400,"journal":{"name":"AppliedMath","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-04-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140690843","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Spontaneous Imbibition and an Interface-Electrostatics-Based Model of the Transition Zone Thickness of Hydrocarbon Reservoirs and Their Theoretical Interpretations 油气藏过渡带厚度的自发浸润和基于界面-静电模型及其理论解释
Pub Date : 2024-04-16 DOI: 10.3390/appliedmath4020027
M. Amadu, A. Miadonye
The transition zone (TZ) of hydrocarbon reservoirs is an integral part of the hydrocarbon pool which contains a substantial fraction of the deposit, particularly in carbonate petroleum systems. Consequently, knowledge of its thickness and petrophysical properties, viz. its pore size distribution and wettability characteristic, is critical to optimizing hydrocarbon production in this zone. Using classical formation evaluation techniques, the thickness of the transition zone has been estimated, using well logging methods including resistivity and Nuclear Magnetic Resonance, among others. While hydrocarbon fluids’ accumulation in petroleum reservoirs occurs due to the migration and displacement of originally water-filled potential structural and stratigraphic traps, the development of their TZ integrates petrophysical processes that combine spontaneous capillary imbibition and wettability phenomena. In the literature, wettability phenomena have been shown to also be governed by electrostatic phenomena. Therefore, given that reservoir rocks are aggregates of minerals with ionizable surface groups that facilitate the development of an electric double layer, a definite theoretical relationship between the TZ and electrostatic theory must be feasible. Accordingly, a theoretical approach to estimating the TZ thickness, using the electrostatic theory and based on the electric double layer theory, is attractive, but this is lacking in the literature. Herein, we fill the knowledge gap by using the interfacial electrostatic theory based on the fundamental tenets of the solution to the Poisson–Boltzmann mean field theory. Accordingly, we have used an existing model of capillary rise based on free energy concepts to derive a capillary rise equation that can be used to theoretically predict observations based on the TZ thickness of different reservoir rocks, using well-established formation evaluation methods. The novelty of our work stems from the ability of the model to theoretically and accurately predict the TZ thickness of the different lithostratigraphic units of hydrocarbon reservoirs, because of the experimental accessibility of its model parameters.
碳氢化合物储层的过渡带(TZ)是碳氢化合物池不可分割的一部分,它包含了相当一部分的矿藏,尤其是在碳酸盐岩石油系统中。因此,了解过渡带的厚度和岩石物理特性,即孔径分布和润湿特性,对于优化过渡带的碳氢化合物生产至关重要。利用经典的地层评估技术,采用电阻率和核磁共振等测井方法估算过渡带的厚度。油气流体在石油储层中的积聚是由于原本充满水的潜在构造和地层陷阱的迁移和位移造成的,而油气流体过渡带的开发则综合了自发毛细管浸润和润湿现象的岩石物理过程。文献表明,润湿现象也受静电现象支配。因此,鉴于储层岩石是具有可电离表面基团的矿物集合体,这些表面基团有助于形成电双层,因此 TZ 与静电理论之间的明确理论关系必须是可行的。因此,利用静电理论并以电双层理论为基础来估算 TZ 厚度的理论方法很有吸引力,但文献中缺乏这方面的研究。在此,我们以泊松-波尔兹曼平均场理论解的基本原理为基础,利用界面静电理论填补了这一知识空白。因此,我们利用现有的基于自由能概念的毛细管上升模型,推导出了一个毛细管上升方程,该方程可用于利用成熟的地层评估方法,根据不同储层岩石的 TZ 厚度从理论上预测观测结果。我们工作的新颖之处在于,由于模型参数可通过实验获得,该模型能够从理论上准确预测油气储层不同岩性地层单元的 TZ 厚度。
{"title":"Spontaneous Imbibition and an Interface-Electrostatics-Based Model of the Transition Zone Thickness of Hydrocarbon Reservoirs and Their Theoretical Interpretations","authors":"M. Amadu, A. Miadonye","doi":"10.3390/appliedmath4020027","DOIUrl":"https://doi.org/10.3390/appliedmath4020027","url":null,"abstract":"The transition zone (TZ) of hydrocarbon reservoirs is an integral part of the hydrocarbon pool which contains a substantial fraction of the deposit, particularly in carbonate petroleum systems. Consequently, knowledge of its thickness and petrophysical properties, viz. its pore size distribution and wettability characteristic, is critical to optimizing hydrocarbon production in this zone. Using classical formation evaluation techniques, the thickness of the transition zone has been estimated, using well logging methods including resistivity and Nuclear Magnetic Resonance, among others. While hydrocarbon fluids’ accumulation in petroleum reservoirs occurs due to the migration and displacement of originally water-filled potential structural and stratigraphic traps, the development of their TZ integrates petrophysical processes that combine spontaneous capillary imbibition and wettability phenomena. In the literature, wettability phenomena have been shown to also be governed by electrostatic phenomena. Therefore, given that reservoir rocks are aggregates of minerals with ionizable surface groups that facilitate the development of an electric double layer, a definite theoretical relationship between the TZ and electrostatic theory must be feasible. Accordingly, a theoretical approach to estimating the TZ thickness, using the electrostatic theory and based on the electric double layer theory, is attractive, but this is lacking in the literature. Herein, we fill the knowledge gap by using the interfacial electrostatic theory based on the fundamental tenets of the solution to the Poisson–Boltzmann mean field theory. Accordingly, we have used an existing model of capillary rise based on free energy concepts to derive a capillary rise equation that can be used to theoretically predict observations based on the TZ thickness of different reservoir rocks, using well-established formation evaluation methods. The novelty of our work stems from the ability of the model to theoretically and accurately predict the TZ thickness of the different lithostratigraphic units of hydrocarbon reservoirs, because of the experimental accessibility of its model parameters.","PeriodicalId":503400,"journal":{"name":"AppliedMath","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-04-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140695140","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
A New Approach to Understanding Quantum Mechanics: Illustrated Using a Pedagogical Model over ℤ2 理解量子力学的新方法:使用ℤ2 上的教学模型进行说明
Pub Date : 2024-04-09 DOI: 10.3390/appliedmath4020025
David Ellerman
The new approach to quantum mechanics (QM) is that the mathematics of QM is the linearization of the mathematics of partitions (or equivalence relations) on a set. This paper develops those ideas using vector spaces over the field Z2={0.1} as a pedagogical or toy model of (finite-dimensional, non-relativistic) QM. The 0,1-vectors are interpreted as sets, so the model is “quantum mechanics over sets” or QM/Sets. The key notions of partitions on a set are the logical-level notions to model distinctions versus indistinctions, definiteness versus indefiniteness, or distinguishability versus indistinguishability. Those pairs of concepts are the key to understanding the non-classical ‘weirdness’ of QM. The key non-classical notion in QM is the notion of superposition, i.e., the notion of a state that is indefinite between two or more definite- or eigen-states. As Richard Feynman emphasized, all the weirdness of QM is illustrated in the double-slit experiment, so the QM/Sets version of that experiment is used to make the key points.
量子力学(QM)的新方法是,量子力学数学是集合上分区(或等价关系)数学的线性化。本文使用域 Z2={0.1} 上的矢量空间作为(有限维、非相对论)量子力学的教学或玩具模型,对这些观点进行了阐释。0,1-向量被解释为集合,因此这个模型是 "集合上的量子力学 "或 QM/集合。集合上的分区的关键概念是逻辑层面的概念,用以模拟区分与不区分、确定性与不确定性,或可区分性与不可区分性。这些概念对是理解 QM 的非经典 "怪异性 "的关键。QM 中的关键非经典概念是叠加概念,即在两个或多个定态或特征态之间的不确定态的概念。正如理查德-费曼(Richard Feynman)所强调的那样,QM 的所有怪异之处都在双缝实验中得到了说明,因此,我们使用该实验的 QM/Sets 版本来说明关键要点。
{"title":"A New Approach to Understanding Quantum Mechanics: Illustrated Using a Pedagogical Model over ℤ2","authors":"David Ellerman","doi":"10.3390/appliedmath4020025","DOIUrl":"https://doi.org/10.3390/appliedmath4020025","url":null,"abstract":"The new approach to quantum mechanics (QM) is that the mathematics of QM is the linearization of the mathematics of partitions (or equivalence relations) on a set. This paper develops those ideas using vector spaces over the field Z2={0.1} as a pedagogical or toy model of (finite-dimensional, non-relativistic) QM. The 0,1-vectors are interpreted as sets, so the model is “quantum mechanics over sets” or QM/Sets. The key notions of partitions on a set are the logical-level notions to model distinctions versus indistinctions, definiteness versus indefiniteness, or distinguishability versus indistinguishability. Those pairs of concepts are the key to understanding the non-classical ‘weirdness’ of QM. The key non-classical notion in QM is the notion of superposition, i.e., the notion of a state that is indefinite between two or more definite- or eigen-states. As Richard Feynman emphasized, all the weirdness of QM is illustrated in the double-slit experiment, so the QM/Sets version of that experiment is used to make the key points.","PeriodicalId":503400,"journal":{"name":"AppliedMath","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-04-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140723710","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Analyzing Small-Signal Stability in a Multi-Source Single-Area Power System with a Load-Frequency Controller Coordinated with a Photovoltaic System 分析带有与光伏系统协调的负载频率控制器的多源单区电力系统的小信号稳定性
Pub Date : 2024-04-03 DOI: 10.3390/appliedmath4020024
G. Shahgholian, Arman Fathollahi
The frequency deviation from the nominal working frequency in power systems is a consequence of the imbalance between total electrical loads and the aggregate power supplied by production units. The sensitivity of energy system frequency to both minor and major load variations underscore the need for effective frequency load control mechanisms. In this paper, frequency load control in single-area power system with multi-source energy is analysed and simulated. Also, the effect of the photovoltaic system on the frequency deviation changes in the energy system is shown. In the single area energy system, the dynamics of thermal turbine with reheat, thermal turbine without reheat and hydro turbine are considered. The simulation results using Simulink/Matlab and model analysis using eigenvalue analysis show the dynamic behaviour of the power system in response to changes in the load.
电力系统的频率偏离额定工作频率,是总电力负荷与生产单位提供的总功率之间不平衡的结果。能源系统频率对主要和次要负荷变化的敏感性凸显了对有效频率负荷控制机制的需求。本文分析并模拟了多能源单区电力系统的频率负荷控制。同时,还展示了光伏系统对能源系统频率偏差变化的影响。在单区能源系统中,考虑了带再热的热力涡轮机、不带再热的热力涡轮机和水力涡轮机的动态。使用 Simulink/Matlab 进行的仿真结果和使用特征值分析进行的模型分析表明了电力系统响应负荷变化的动态行为。
{"title":"Analyzing Small-Signal Stability in a Multi-Source Single-Area Power System with a Load-Frequency Controller Coordinated with a Photovoltaic System","authors":"G. Shahgholian, Arman Fathollahi","doi":"10.3390/appliedmath4020024","DOIUrl":"https://doi.org/10.3390/appliedmath4020024","url":null,"abstract":"The frequency deviation from the nominal working frequency in power systems is a consequence of the imbalance between total electrical loads and the aggregate power supplied by production units. The sensitivity of energy system frequency to both minor and major load variations underscore the need for effective frequency load control mechanisms. In this paper, frequency load control in single-area power system with multi-source energy is analysed and simulated. Also, the effect of the photovoltaic system on the frequency deviation changes in the energy system is shown. In the single area energy system, the dynamics of thermal turbine with reheat, thermal turbine without reheat and hydro turbine are considered. The simulation results using Simulink/Matlab and model analysis using eigenvalue analysis show the dynamic behaviour of the power system in response to changes in the load.","PeriodicalId":503400,"journal":{"name":"AppliedMath","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-04-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140749484","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
期刊
AppliedMath
全部 Acc. Chem. Res. ACS Applied Bio Materials ACS Appl. Electron. Mater. ACS Appl. Energy Mater. ACS Appl. Mater. Interfaces ACS Appl. Nano Mater. ACS Appl. Polym. Mater. ACS BIOMATER-SCI ENG ACS Catal. ACS Cent. Sci. ACS Chem. Biol. ACS Chemical Health & Safety ACS Chem. Neurosci. ACS Comb. Sci. ACS Earth Space Chem. ACS Energy Lett. ACS Infect. Dis. ACS Macro Lett. ACS Mater. Lett. ACS Med. Chem. Lett. ACS Nano ACS Omega ACS Photonics ACS Sens. ACS Sustainable Chem. Eng. ACS Synth. Biol. Anal. Chem. BIOCHEMISTRY-US Bioconjugate Chem. BIOMACROMOLECULES Chem. Res. Toxicol. Chem. Rev. Chem. Mater. CRYST GROWTH DES ENERG FUEL Environ. Sci. Technol. Environ. Sci. Technol. Lett. Eur. J. Inorg. Chem. IND ENG CHEM RES Inorg. Chem. J. Agric. Food. Chem. J. Chem. Eng. Data J. Chem. Educ. J. Chem. Inf. Model. J. Chem. Theory Comput. J. Med. Chem. J. Nat. Prod. J PROTEOME RES J. Am. Chem. Soc. LANGMUIR MACROMOLECULES Mol. Pharmaceutics Nano Lett. Org. Lett. ORG PROCESS RES DEV ORGANOMETALLICS J. Org. Chem. J. Phys. Chem. J. Phys. Chem. A J. Phys. Chem. B J. Phys. Chem. C J. Phys. Chem. Lett. Analyst Anal. Methods Biomater. Sci. Catal. Sci. Technol. Chem. Commun. Chem. Soc. Rev. CHEM EDUC RES PRACT CRYSTENGCOMM Dalton Trans. Energy Environ. Sci. ENVIRON SCI-NANO ENVIRON SCI-PROC IMP ENVIRON SCI-WAT RES Faraday Discuss. Food Funct. Green Chem. Inorg. Chem. Front. Integr. Biol. J. Anal. At. Spectrom. J. Mater. Chem. A J. Mater. Chem. B J. Mater. Chem. C Lab Chip Mater. Chem. Front. Mater. Horiz. MEDCHEMCOMM Metallomics Mol. Biosyst. Mol. Syst. Des. Eng. Nanoscale Nanoscale Horiz. Nat. Prod. Rep. New J. Chem. Org. Biomol. Chem. Org. Chem. Front. PHOTOCH PHOTOBIO SCI PCCP Polym. Chem.
×
引用
GB/T 7714-2015
复制
MLA
复制
APA
复制
导出至
BibTeX EndNote RefMan NoteFirst NoteExpress
×
0
微信
客服QQ
Book学术公众号 扫码关注我们
反馈
×
意见反馈
请填写您的意见或建议
请填写您的手机或邮箱
×
提示
您的信息不完整,为了账户安全,请先补充。
现在去补充
×
提示
您因"违规操作"
具体请查看互助需知
我知道了
×
提示
现在去查看 取消
×
提示
确定
Book学术官方微信
Book学术文献互助
Book学术文献互助群
群 号:481959085
Book学术
文献互助 智能选刊 最新文献 互助须知 联系我们:info@booksci.cn
Book学术提供免费学术资源搜索服务,方便国内外学者检索中英文文献。致力于提供最便捷和优质的服务体验。
Copyright © 2023 Book学术 All rights reserved.
ghs 京公网安备 11010802042870号 京ICP备2023020795号-1