Miguel Hidalgo-Rodriguez, Edmanuel Cruz, Cesar Pinzon-Acosta
et al.
Real-time vessel tracking and environmental assessment in developing regions face significant challenges due to the high cost and proprietary constraints of commercial Automatic Identification System (AIS) services. We introduce MAGI, an open-source, low-cost, IoT-distributed architecture that integrates Orange Pi 5 edge nodes with software-defined radio (SDR) AIS receivers and containerized microservices to capture, preprocess, and stream AIS messages. During a ten-day field campaign in Panama, our decentralized deployment processed over 500,000 AIS transmissions, achieving 99% uptime and delivering vessel position and speed updates with sub-second latency. Based on the collected data, we also evaluated system scalability, energy consumption, and per node cost, demonstrating that a complete coastal network can be deployed for under USD 1200 per site. These results confirm that MAGI is a scalable, secure, and affordable IoT solution for AIS-based vessel tracking and environmental monitoring in resource-constrained settings.
Option pricing is crucial in enabling investors to hedge against risks. The Black–Scholes option pricing model is widely used for this purpose. This paper investigates whether the Black–Scholes model is a good indicator of option pricing in the United States stock market. We examine the relevance of the Black–Scholes model to certain stocks using paired sample t-test and Corrado and Miller’s approximation for the implied volatility. Empirical tests are applied to determine the significance of the relationship between the actual market values and the Black–Scholes model values. Paired sample t-tests are applied to 582 call options and 579 put options. The empirical test results show that there is no significant difference between the actual market premium value and the Black–Scholes model premium value for seven out of nine stocks considered for call options, and four out of nine stocks considered for put options. Thus, we conclude that the Black–Scholes option pricing model can be used to price call options but is not suitable for pricing put options in the United States stock market.
The development of science and technology constantly injects new vitality into dance performance and creation. Among them, three-dimensional (3D) vision technology provides novel ideas for the innovation and artistry of dance performances, expands the forms of dance performances and the way to present dance works, and brings a brand-new viewing experience to the audience. Nowadays, 3D vision technology in dance has been widely researched and applied. This review presents the background of the 3D vision technology application in the dance field, analyzes the main types of technology and working principles for realizing 3D vision, summarizes the research and application of the 3D vision technology in dance creation, perception, enhancement, and dance teaching, and finally looks forward to the development prospect of the 3D vision technology in the dance.
This study provides a comprehensive exploration of the qualitative analysis of a hybrid system of pantograph equations with fractional order and a p-Laplacian operator. The existence of the solution of the system is explicitly established within the context of Riemann–Liouville’s fractional order operator, employing the Arzelà–Ascoli theorem for validation. The establishment of uniqueness criteria is accomplished by the utilization of the Banach contractive technique. In addition, the examination of solution stability is conducted using the Hyers–Ulam (HU) stability technique. In order to enhance the credibility of our main conclusions, we have included a representative and illustrative example in the concluding section of the study. This work serve to offer a thorough and applicable comprehension of the mathematical framework that has been proposed.
The propagation of elastic waves in hyperelastic materials is described by a nonlinear system of partial differential equations (PDEs) governing the material’s motion. Hyperelastic materials are characterized by a strain–energy density function that correlates material deformation with stored elastic energy. For simplicity, we focus on the one-dimensional case where the displacement field, denoted as ϕ(x,t), signifies material deformation along the x-direction at position x and time t. The governing equation for elastic wave propagation in hyperelastic materials is derived from the strain–energy density function and associated stress–strain relations. In this study, Lie symmetry analysis is used to examine a nonlinear system of such equations relevant to the propagation of elastic waves in hyperelastic materials. The resulting equations are solved by applying Lie’s invariance criterion, yielding a ten-dimensional Lie algebra. An optimal system is derived from this algebra, allowing for the identification of invariant solutions under certain conditions. Additionally, the multiplier approach and Ibragimov’s new conservation laws are utilized to obtain the conservation laws for this coupled system of elastic waves. The outcome presented here is innovative and suggests utilizing the Lie symmetry method for investigating hyperelastic materials.
This paper is aimed at constructing and analyzing a fitted approach for singularly perturbed time delay parabolic problems with two small parameters. The proposed computational scheme comprises the implicit Euler and especially finite difference method for the time and space variable discretization, respectively, on uniform step size. The stability and convergence analysis of the method is provided and is first-order parameter uniform convergent. Further, the numerical results depict that the present method is more convergent than some methods available in the literature.
Gerrit Großmann, Julian Zimmerlin, Michael Backenköhler
et al.
Abstract Problem setting Stochastic dynamical systems in which local interactions give rise to complex emerging phenomena are ubiquitous in nature and society. This work explores the problem of inferring the unknown interaction structure (represented as a graph) of such a system from measurements of its constituent agents or individual components (represented as nodes). We consider a setting where the underlying dynamical model is unknown and where different measurements (i.e., snapshots) may be independent (e.g., may stem from different experiments). Method Our method is based on the observation that the temporal stochastic evolution manifests itself in local patterns. We show that we can exploit these patterns to infer the underlying graph by formulating a masked reconstruction task. Therefore, we propose GINA (Graph Inference Network Architecture), a machine learning approach to simultaneously learn the latent interaction graph and, conditioned on the interaction graph, the prediction of the (masked) state of a node based only on adjacent vertices. Our method is based on the hypothesis that the ground truth interaction graph—among all other potential graphs—allows us to predict the state of a node, given the states of its neighbors, with the highest accuracy. Results We test this hypothesis and demonstrate GINA’s effectiveness on a wide range of interaction graphs and dynamical processes. We find that our paradigm allows to reconstruct the ground truth interaction graph in many cases and that GINA outperforms statistical and machine learning baseline on independent snapshots as well as on time series data.
Big data have been used widely in many areas, including the transportation industry. Using various data sources, traffic states can be well estimated and further predicted to improve the overall operation efficiency. Combined with this trend, this study presents an up-to-date survey of open data and big data tools used for traffic estimation and prediction. Different data types are categorized, and off-the-shelf tools are introduced. To further promote the use of big data for traffic estimation and prediction tasks, challenges and future directions are given for future studies.
Ricardo Román-Gutiérrez, Carlos Chávez-Negrete, Francisco Domínguez-Mota
et al.
Density-driven groundwater flows are described by nonlinear coupled differential equations. Due to its importance in engineering and earth science, several linearizations and semi-linearization schemes for approximating their solution have been proposed. Among the more efficient are the combinations of Newtonian iterations for the spatially discretized system obtained by either scalar homotopy methods, fictitious time methods, or meshless generalized finite difference method, with several implicit methods for the time integration. However, when these methods are used, some parameters need to be determined, in some cases, even manually. To overcome this problem, this paper presents a novel generalized finite differences scheme combined with an adaptive step-size method, which can be applied for solving the governing equations of interest on non-rectangular structured and unstructured grids. The proposed method is tested on the Henry and the Elder problems to verify the accuracy and the stability of the proposed numerical scheme.
We describe a quasi-variable meshes implicit compact finite-difference discretization having an accuracy of order four in the spatial direction and second-order in the temporal direction for obtaining numerical solution values of generalized Burger’s-Huxley and Burger’s-Fisher equations. The new difference scheme is derived for a general one-dimension quasi-linear parabolic partial differential equation on a quasi-variable meshes network to the extent that the magnitude of local truncation error of the high-order compact scheme remains unchanged in case of uniform meshes network. Practically, quasi-variable meshes high-order compact schemes yield more precise solution compared with uniform meshes high-order schemes of the same magnitude. A detailed exposition of the new scheme has been introduced and discussed the Fourier analysis based stability theory. The computational results with generalized Burger’s-Huxley equation and Burger’s-Fisher equation are obtained using quasi-variable meshes high-order compact scheme and compared with a numerical solution using uniform meshes high-order schemes to demonstrate capability and accuracy.
Ronildo Cavalcante da Silva, Egnilson Miranda de Moura
Este trabalho, origina-se de uma dissertação de mestrado e fundamenta-se no construcionismo de Seymour Papert (1928-2016), e descreve a construção e utilização de um aplicativo denominado e-trigonoplan, que utiliza a estrutura e os recursos do Microsoft Excel com vistas à aprendizagem de funções trigonométricas pelos alunos da Unidade Escolar Prof. Abelardo Pereira, em Brejo do Piauí-PI. Objetivou-se investigar as contribuições da construção desse aplicativo para o ensino-aprendizagem de funções trigonométricas pelos alunos da 2ª série do ensino médio na escola supracitada. Elencaram-se como objetivos específicos: verificar os conhecimentos dos estudantes em relação às funções trigonométricas; construir, com os alunos, a planilha-aplicativo para o ensino-aprendizagem de funções trigonométricas; verificar os aspectos que contribuem e as dificuldades encontradas na construção da planilha-aplicativo na aprendizagem de funções trigonométricas pelos estudantes. Para tanto, realizou-se pesquisa de campo, de natureza básica, exploratória e descritiva, mediante abordagem qualitativa. Os resultados apontam um caminho promissor quanto o uso do aplicativo e-trigonoplan.
Special aspects of education, Applied mathematics. Quantitative methods
We study two numerical techniques based on the homotopy perturba tion transform method (HPTM) and the fractional Adams–Bashforth method (FABM) for solving a class of nonlinear time-fractional differential equations involving the Caputo–Prabhakar fractional derivatives. In this manuscript, the convergence for numerical solutions obtained using HPTM and the con vergence and stability for numerical solutions obtained using FABM are inves tigated. We compare the solutions obtained by the HPTM and the FABM for some nonlinear time-fractional differential equations. Moreover, some numer ical examples are demonstrated in order to show the validity and reliability of the suggested methods.
We discuss the controllability and observability of time-invariant (continuous time) linear systems with interval coefficients using the notion of being full rank of interval matrices. The most important advantage of the proposed attitude is to consider these two essential concepts, that is, control lability and observability, in interval time-invariant linear systems, which, in turn, may play important roles in the analysis of uncertain systems. Some different definitions on to be full rank of matrices have been utilized to propose different views on the controllability and observability of interval linear systems according to different criteria. Finally, in several control-observation processes, the controllability and observability are evaluated based on the given achievements.