Skip to Content

Mathematics, Volume 9, Issue 17

2021 September-1 - 161 articles

Cover Story: The boundary value problem for the steady Navier–Stokes system is considered in a 2D multiply-connected bounded domain, with the boundary having a power cusp singularity at the point O. The case of a boundary value with nonzero flow rates over connected components of the boundary is studied. It is also supposed that there is a source/sink in O. In this case, the solution necessarily has an infinite Dirichlet integral. The existence of a solution to this problem is proved with the assumption that the flow rates are “sufficiently small”. This condition does not require the norm of the boundary data to be small. The solution is constructed as the sum of a function with the finite Dirichlet integral and a singular part coinciding with the asymptotic decomposition near the cusp point. View this paper.
  • Issues are regarded as officially published after their release is announced to the table of contents alert mailing list .
  • You may sign up for email alerts to receive table of contents of newly released issues.
  • PDF is the official format for papers published in both, html and pdf forms. To view the papers in pdf format, click on the "PDF Full-text" link, and use the free Adobe Reader to open them.

Articles (161)

  • Feature Paper
  • Article
  • Open Access
8 Citations
3,978 Views
12 Pages

A Framework for Economically Optimal Operation of Explosive Waste Incineration Process to Reduce NOx Emission Concentration

  • Sunghyun Cho,
  • Dongwoo Kang,
  • Joseph Sang-Il Kwon,
  • Minsu Kim,
  • Hyungtae Cho,
  • Il Moon and
  • Junghwan Kim

6 September 2021

Explosives, especially those used for military weapons, have a short lifespan and their performance noticeably deteriorates over time. These old explosives need to be disposed of safely. Fluidized bed incinerators (FBIs) are safe for disposal of expl...

  • Article
  • Open Access
62 Citations
6,855 Views
17 Pages

6 September 2021

Engineering data are often highly nonlinear and contain high-frequency noise, so the Levenberg–Marquardt (LM) algorithm may not converge when a neural network optimized by the algorithm is trained with engineering data. In this work, we analyzed the...

  • Article
  • Open Access
3 Citations
1,911 Views
17 Pages

6 September 2021

In this paper, the thermal explosion model described by a nonlinear boundary value problem is studied. Firstly, we prove the comparison principle under nonlinear boundary conditions. Secondly, using the sub-super solution theorem, we prove the existe...

  • Article
  • Open Access
4 Citations
2,431 Views
35 Pages

6 September 2021

This paper proposes and studies the reachability of a singular regular dynamic discrete Leontief-type economic model which includes production industries, recycling industries, and non-renewable products in an integrated way. The designed prefixed fi...

  • Article
  • Open Access
6 Citations
2,615 Views
11 Pages

6 September 2021

In the present paper, we consider the problem of dichotomic behaviors of dynamical systems described by discrete-time skew evolution cocycles in Banach spaces. We study two concepts of uniform dichotomy: uniform exponential dichotomy and uniform poly...

  • Article
  • Open Access
19 Citations
3,004 Views
12 Pages

5 September 2021

Load leveling problems and energy storage systems can be modeled in the form of Volterra integral equations (VIE) with a discontinuous kernel. The Lagrange–collocation method is applied for solving the problem. Proving a theorem, we discuss the preci...

  • Article
  • Open Access
5 Citations
2,801 Views
15 Pages

5 September 2021

In this paper, we investigate the stability of equilibrium in the stage-structured and density-dependent predator–prey system with Beddington–DeAngelis functional response. First, by checking the sign of the real part for eigenvalue, local stability...

  • Article
  • Open Access
12 Citations
3,795 Views
13 Pages

Evaluation of the Work-Integrated Learning Methodology: Teaching Marketing through Practitioner Experience in the Classroom

  • Luis-Alberto Casado-Aranda,
  • Juan Sánchez-Fernández,
  • Francisco Javier Montoro-Ríos and
  • María Isabel Arias Horcajadas

5 September 2021

The teaching methodology in university marketing subjects has traditionally been based on “lecture classes”, which have proved to be insufficient for providing students with professional skills that can be directly applied in the workplace. This rese...

  • Article
  • Open Access
3 Citations
2,796 Views
15 Pages

5 September 2021

Reversible data hiding in encrypted images (RDHEI) is a technology which embeds secret data into encrypted images in a reversible way. In this paper, we proposed a novel high-capacity RDHEI method which is based on the compression of prediction error...

  • Article
  • Open Access
9 Citations
4,296 Views
30 Pages

5 September 2021

The efficient operation of emergency medical services is critical for any society. Typically, optimisation and simulation models support decisions on emergency ambulance stations’ locations and ambulance management strategies. Essential inputs for su...

  • Article
  • Open Access
10 Citations
3,703 Views
19 Pages

Optimization of Microjet Location Using Surrogate Model Coupled with Particle Swarm Optimization Algorithm

  • Mohammad Owais Qidwai,
  • Irfan Anjum Badruddin,
  • Noor Zaman Khan,
  • Mohammad Anas Khan and
  • Saad Alshahrani

5 September 2021

This study aimed to present the design methodology of microjet heat sinks with unequal jet spacing, using a machine learning technique which alleviates hot spots in heat sinks with non-uniform heat flux conditions. Latin hypercube sampling was used t...

  • Article
  • Open Access
4 Citations
3,028 Views
23 Pages

5 September 2021

Simulation programs are widely used in the design of analog electronic circuits to analyze their behavior and to predict the response of a circuit to variations in the circuit components. A fuzzy inference system (FIS) in combination with these simul...

  • Article
  • Open Access
6 Citations
4,209 Views
19 Pages

Analysis of the Tax Compliance in the EU: VECM and SEM

  • Marius-Răzvan Surugiu,
  • Cristina-Raluca Mazilescu and
  • Camelia Surugiu

5 September 2021

Tax compliance is an important indicator for the proper functioning of the tax authority, influencing the budget revenue level. In this study, a Vector Error Correction Model (VECM) analysis was developed to identify the long-term relationships betwe...

  • Article
  • Open Access
14 Citations
4,689 Views
13 Pages

Mathematical Modeling, Analysis and Evaluation of the Complexity of Flight Paths of Groups of Unmanned Aerial Vehicles in Aviation and Transport Systems

  • Andrey Kositzyn,
  • Denis Serdechnyy,
  • Sergey Korchagin,
  • Ekaterina Pleshakova,
  • Petr Nikitin and
  • Natalia Kurileva

5 September 2021

Recently, we have seen the rapidly growing popularity of unmanned aerial vehicles. This is due to some advantages, namely portability, the ability to fly over hard-to-reach areas without human intervention. They are also widely used for commercial pu...

  • Article
  • Open Access
4 Citations
2,989 Views
20 Pages

Evaluation of Clustering Algorithms on HPC Platforms

  • Juan M. Cebrian,
  • Baldomero Imbernón,
  • Jesús Soto and
  • José M. Cecilia

4 September 2021

Clustering algorithms are one of the most widely used kernels to generate knowledge from large datasets. These algorithms group a set of data elements (i.e., images, points, patterns, etc.) into clusters to identify patterns or common features of a s...

  • Article
  • Open Access
18 Citations
4,669 Views
19 Pages

A Hybrid Genetic Algorithm for the Simple Assembly Line Balancing Problem with a Fixed Number of Workstations

  • Eduardo Álvarez-Miranda,
  • Jordi Pereira,
  • Harold Torrez-Meruvia and
  • Mariona Vilà

4 September 2021

The assembly line balancing problem is a classical optimisation problem whose objective is to assign each production task to one of the stations on the assembly line so that the total efficiency of the line is maximized. This study proposes a novel h...

  • Article
  • Open Access
10 Citations
2,513 Views
16 Pages

4 September 2021

We consider a linear control system defined by a scalar stationary linear differential equation in the real or complex space with multiple non-commensurate lumped and distributed delays in the state. In the system, the input is a linear combination o...

  • Article
  • Open Access
10 Citations
2,144 Views
12 Pages

Non-Uniform Spline Quasi-Interpolation to Extract the Series Resistance in Resistive Switching Memristors for Compact Modeling Purposes

  • María José Ibáñez,
  • Domingo Barrera,
  • David Maldonado,
  • Rafael Yáñez and
  • Juan Bautista Roldán

4 September 2021

An advanced new methodology is presented to improve parameter extraction in resistive memories. The series resistance and some other parameters in resistive memories are obtained, making use of a two-stage algorithm, where the second one is based on...

  • Article
  • Open Access
38 Citations
4,562 Views
27 Pages

Fractional Dynamics of Stuxnet Virus Propagation in Industrial Control Systems

  • Zaheer Masood,
  • Muhammad Asif Zahoor Raja,
  • Naveed Ishtiaq Chaudhary,
  • Khalid Mehmood Cheema and
  • Ahmad H. Milyani

4 September 2021

The designed fractional order Stuxnet, the virus model, is analyzed to investigate the spread of the virus in the regime of isolated industrial networks environment by bridging the air-gap between the traditional and the critical control network infr...

  • Feature Paper
  • Article
  • Open Access
2,086 Views
13 Pages

4 September 2021

Let F be the normalized Hecke-eigen cusp form for the full modular group and ζ(s,F) be the corresponding zeta-function. In the paper, the joint universality theorem on the approximation of a collection of analytic functions by shifts (ζ(s+ih1τ,F),,ζ...

  • Article
  • Open Access
2 Citations
3,499 Views
20 Pages

Algorithmic Determination of a Large Integer in the Two-Term Machin-like Formula for π

  • Sanjar M. Abrarov,
  • Rajinder K. Jagpal,
  • Rehan Siddiqui and
  • Brendan M. Quine

4 September 2021

In our earlier publication we have shown how to compute by iteration a rational number u2,k in the two-term Machin-like formula for π of the kind π4=2k1arctan1u1,k+arctan1u2,k,kZ,k1, where u1,k can be chosen as an integer u1,k=ak/2ak1 with neste...

  • Article
  • Open Access
29 Citations
4,136 Views
22 Pages

A Novel MADM Framework under q-Rung Orthopair Fuzzy Bipolar Soft Sets

  • Ghous Ali,
  • Hanan Alolaiyan,
  • Dragan Pamučar,
  • Muhammad Asif and
  • Nimra Lateef

4 September 2021

In many real-life problems, decision-making is reckoned as a powerful tool to manipulate the data involving imprecise and vague information. To fix the mathematical problems containing more generalized datasets, an emerging model called q-rung orthop...

  • Article
  • Open Access
2 Citations
3,368 Views
16 Pages

Planar Typical Bézier Curves with a Single Curvature Extremum

  • Chuan He,
  • Gang Zhao,
  • Aizeng Wang,
  • Shaolin Li and
  • Zhanchuan Cai

3 September 2021

This paper focuses on planar typical Bézier curves with a single curvature extremum, which is a supplement of typical curves with monotonic curvature by Y. Mineur et al. We have proven that the typical curve has at most one curvature extremum and giv...

  • Article
  • Open Access
22 Citations
2,774 Views
13 Pages

3 September 2021

Soft ω-local indiscreetness as a weaker form of both soft local countability and soft local indiscreetness is introduced. Then soft ω-regularity as a weaker form of both soft regularity and soft ω-local indiscreetness is defined and investigated. Add...

  • Article
  • Open Access
5 Citations
2,727 Views
9 Pages

On a One-Dimensional Hydrodynamic Model for Semiconductors with Field-Dependent Mobility

  • Giuseppe Alì,
  • Francesco Lamonaca,
  • Carmelo Scuro and
  • Isabella Torcicollo

3 September 2021

We consider a one-dimensional, isentropic, hydrodynamical model for a unipolar semiconductor, with the mobility depending on the electric field. The mobility is related to the momentum relaxation time, and field-dependent mobility models are commonly...

  • Article
  • Open Access
3 Citations
3,511 Views
19 Pages

3 September 2021

The Benjamini–Hochberg procedure is one of the most used scientific methods up to date. It is widely used in the field of genetics and other areas where the problem of multiple comparison arises frequently. In this paper we show that under fairly gen...

  • Article
  • Open Access
7 Citations
4,832 Views
22 Pages

A Method of Image Quality Assessment for Text Recognition on Camera-Captured and Projectively Distorted Documents

  • Julia Shemiakina,
  • Elena Limonova,
  • Natalya Skoryukina,
  • Vladimir V. Arlazarov and
  • Dmitry P. Nikolaev

3 September 2021

In this paper, we consider the problem of identity document recognition in images captured with a mobile device camera. A high level of projective distortion leads to poor quality of the restored text images and, hence, to unreliable recognition resu...

  • Article
  • Open Access
8 Citations
4,073 Views
19 Pages

3 September 2021

Currently, big sensor data arise in a wide spectrum of Industry 4.0, Internet of Things, and Smart City applications. In such subject domains, sensors tend to have a high frequency and produce massive time series in a relatively short time interval....

  • Article
  • Open Access
12 Citations
8,592 Views
20 Pages

3 September 2021

Distance learning due to the COVID-19 lockdown, commonly called emergency remote teaching (ERT), substantially changed the methodology of teaching and possibly students’ perceptions of the quality of lectures. Students’ opinions should be collected a...

  • Article
  • Open Access
7 Citations
2,501 Views
15 Pages

3 September 2021

In this research paper, we solve the problem of synchronization and anti-synchronization of chaotic systems described by discrete and time-delayed variable fractional-order differential equations. To guarantee the synchronization and anti-synchroniza...

  • Article
  • Open Access
22 Citations
6,735 Views
12 Pages

3 September 2021

This study examines how corporate reputation is perceived by investors through the financial performance and equilibrium of several airline companies. We used a sample of 22 companies. Nineteen are listed in the World Airline Awards 2018 ranking base...

  • Article
  • Open Access
4 Citations
3,375 Views
20 Pages

Instruments and Methods for Identifying Indicators of a Digital Entrepreneurial System

  • Jelena Raut,
  • Đorđe Ćelić,
  • Branislav Dudić,
  • Jelena Ćulibrk and
  • Darko Stefanović

3 September 2021

Entrepreneurial ecosystems are the main driver of the widespread trend of digitalization, and they open opportunities for the advancement of the digital economy. The digital economy makes its progress through innovative enterprises that can ensure gl...

  • Article
  • Open Access
19 Citations
4,523 Views
14 Pages

Domination in Fuzzy Directed Graphs

  • Enrico Enriquez,
  • Grace Estrada,
  • Carmelita Loquias,
  • Reuella J Bacalso and
  • Lanndon Ocampo

2 September 2021

A new domination parameter in a fuzzy digraph is proposed to espouse a contribution in the domain of domination in a fuzzy graph and a directed graph. Let GD*=V,A be a directed simple graph, where V is a finite nonempty set and A=x,y:x,yV,xy. A fuz...

  • Article
  • Open Access
5 Citations
2,400 Views
15 Pages

2 September 2021

In the present paper, we study some properties of warped product pointwise semi-slant and hemi-slant submanifolds in Golden Riemannian manifolds, and we construct examples in Euclidean spaces. Additionally, we study some properties of proper warped p...

  • Article
  • Open Access
14 Citations
3,429 Views
14 Pages

2 September 2021

This paper proposes a university teachers’ teaching performance evaluation method based on type-II fuzzy sets (T2 FSs), which solves the problems of fuzziness, complexity and uncertainty in teaching performance evaluation. Firstly, the evaluation ind...

  • Article
  • Open Access
9,033 Views
19 Pages

Measurement in Primary School Mathematics and Science Textbooks

  • Ana B. Montoro,
  • Carmen Gloria Aguayo-Arriagada and
  • Pablo Flores

2 September 2021

The STEM (science, technology, engineering and mathematics) approach to education has acquired considerable prominence among teachers in recent years. Putting forward integrated proposals is nonetheless complex and many educators opt to implement the...

  • Article
  • Open Access
3 Citations
3,788 Views
16 Pages

Impact of Arrhythmia on Myocardial Perfusion: A Computational Model-Based Study

  • Xinyang Ge,
  • Sergey Simakov,
  • Youjun Liu and
  • Fuyou Liang

2 September 2021

(1) Background: Arrhythmia, which is an umbrella term for various types of abnormal rhythms of heartbeat, has a high prevalence in both the general population and patients with coronary artery disease. So far, it remains unclear how different types o...

  • Article
  • Open Access
13 Citations
2,863 Views
18 Pages

2 September 2021

Knowledge-enhanced recommendation (KER) aims to integrate the knowledge graph (KG) into collaborative filtering (CF) for alleviating the sparsity and cold start problems. The state-of-the-art graph neural network (GNN)–based methods mainly focus on e...

  • Article
  • Open Access
2 Citations
1,600 Views
9 Pages

2 September 2021

The paper aims to construct nonlocal PT-symmetric integrable equations of fourth-order, from nonlocal integrable reductions of a fourth-order integrable system associated with the Lie algebra so(3,R). The nonlocalities involved are reverse-space, rev...

  • Article
  • Open Access
12 Citations
2,663 Views
11 Pages

2 September 2021

This paper studies a non-linear viscoelastic wave equation, with non-linear damping and source terms, from the point of view of the Lie groups theory. Firstly, we apply Lie’s symmetries method to the partial differential equation to classify the Lie...

  • Feature Paper
  • Article
  • Open Access
14 Citations
6,049 Views
18 Pages

2 September 2021

The COVID-19 pandemic and the fear experienced by some of the population, along with the lack of mobility due to the restrictions imposed, has modified the social behaviour of Spaniards. This has had a significant effect on the hospitality sector, vi...

  • Article
  • Open Access
5 Citations
4,244 Views
18 Pages

Analysis of Multi-Server Queue with Self-Sustained Servers

  • Alexander Dudin,
  • Olga Dudina,
  • Sergei Dudin and
  • Konstantin Samouylov

2 September 2021

A novel multi-server vacation queuing model is considered. The distinguishing feature of the model, compared to the standard queues, is the self-sufficiency of servers. A server can terminate service and go on vacation independently of the system man...

  • Article
  • Open Access
5 Citations
2,600 Views
15 Pages

Pythagorean Membership Grade Aggregation Operators: Application in Financial knowledge

  • Fabio Blanco-Mesa,
  • Ernesto León-Castro and
  • Jorge Romero-Muñoz

2 September 2021

This paper presents the Pythagorean membership grade induced ordered weighted moving average (PMGIOWMA) operator with some particular cases and theorems. The main advantage of this new operator is that can include the knowledge, expectation, and apti...

  • Article
  • Open Access
4 Citations
2,983 Views
22 Pages

2 September 2021

Worst-case scenario optimization deals with the minimization of the maximum output in all scenarios of a problem, and it is usually formulated as a min-max problem. Employing nested evolutionary algorithms to solve the problem requires numerous funct...

  • Article
  • Open Access
22 Citations
2,657 Views
10 Pages

Relay Synchronization in a Weighted Triplex Network

  • Md Sayeed Anwar,
  • Dibakar Ghosh and
  • Nikita Frolov

2 September 2021

Relay synchronization in multi-layer networks implies inter-layer synchronization between two indirectly connected layers through a relay layer. In this work, we study the relay synchronization in a three-layer multiplex network by introducing degree...

  • Article
  • Open Access
5 Citations
4,461 Views
28 Pages

Dynamic Model of Contingency Flight Crew Planning Extending to Crew Formation

  • Vojtech Graf,
  • Dusan Teichmann,
  • Michal Dorda and
  • Lenka Kontrikova

2 September 2021

The creation of a flight schedule and the associated crew planning are clearly among the most complicated tasks in terms of traffic preparation. Even with a relatively small number of pilots and aircraft, numerous specific constraints arising from re...

  • Article
  • Open Access
36 Citations
3,387 Views
15 Pages

2 September 2021

In this paper, we first discuss the convolution series that are generated by Sonine kernels from a class of functions continuous on a real positive semi-axis that have an integrable singularity of power function type at point zero. These convolution...

  • Article
  • Open Access
45 Citations
4,632 Views
24 Pages

2 September 2021

This article deals with the unsteady flow in rotating circular plates located at a finite distance filled with Reiner-Rivlin nanofluid. The Reiner-Rivlin nanofluid is electrically conducting and incompressible. Furthermore, the nanofluid also accommo...

  • Article
  • Open Access
7 Citations
2,835 Views
32 Pages

2 September 2021

This paper focuses on the construction of deterministic and stochastic extensions of the Gompertz curve by means of generalized fractional derivatives induced by complete Bernstein functions. Precisely, we first introduce a class of linear stochastic...

  • Article
  • Open Access
28 Citations
5,205 Views
32 Pages

Generalized Fractional Bézier Curve with Shape Parameters

  • Syed Ahmad Aidil Adha Said Mad Zain,
  • Md Yushalify Misro and
  • Kenjiro T. Miura

2 September 2021

The construction of new basis functions for the Bézier or B-spline curve has been one of the most popular themes in recent studies in Computer Aided Geometric Design (CAGD). Implementing the new basis functions with shape parameters provides a differ...

of 4

Get Alerted

Add your email address to receive forthcoming issues of this journal.

XFacebookLinkedIn
Mathematics - ISSN 2227-7390