Afrika Matematika最新文献

In this paper, we introduce the notion of a disturbed Fibonacci sequence, and obtain several properties related to Fibonacci sequences, and apply the notion to Fibonacci rabbit farm to adjust the numbers of Fibonacci rabbits.

In this article, our aim is to examine the local metric dimension, dominant local metric dimension and dominant edge metric dimension of zero-divisor graphs associated with finite commutative ring with unity.

Lie point symmetries of the (2+1) sine-Gordon (S-G) equation are shown to be infinite. Through resultant similarity transformations, reduction of the equation is presented. The finite cases of symmetries are employed to obtain one-dimensional optimal system of subalgebras. Finally, Noether symmetries are utilized to determine conserved vectors for both finite and infinite cases.

In this work, we are interested in the existence of solutions for a nonlinear parabolic–elliptic coupled system in inhomogeneous anisotropic Orlicz–Sobolev spaces without assuming the (varvec{Delta _2})-condition on the N-function. The system describes the heat generated within a semiconductor device by an electrical current. This may be seen as a generalization of the well-known thermistor problem. The main purpose of this paper is to prove two main results: the existence of a weak solution via Schauder’s fixed point theorem, and the existence of a capacity solution.

This work is concerned with a wave equation with a logarithmic nonlinearity, by supposing the distributed delay coupled by the fractional conditions. Under suitable hypotheses and negative initial energy, we prove the blow-up of solutions.

Cronbach’s coefficient alpha is one of the most commonly used measures for assessing the internal consistency or reliability of a set of items, ensuring that they measure the same research objectives. It is used as a measure of reliability in fields like education, psychology, sociology, medicine, accounting and economics. Cronbach’s alpha will be estimated for a general covariance matrix using a Bayesian approach and comparing these results to the asymptotic frequentist interval valid under a general covariance matrix framework. Most of the results used in the literature require the compound symmetry assumption for analyses of Cronbach’s alpha. Fiducial and posterior distributions will be derived for Cronbach’s alpha in the case of the bivariate normal distribution. Various objective priors will be considered for the variance components and the correlation coefficient. The posterior distribution of one of the priors considered corresponds to the fiducial distribution. The performance of these priors will be compared to an asymptotic frequentist interval often used in the literature. A simulation study will be considered to compare the performance of the priors and the asymptotic interval, where the coverage rates and average interval lengths will be computed. The simulation study showed that even though the asymptotic interval improved in the case of larger sample sizes, the Bayesian approach still consistently outperformed the asymptotic frequentist interval.

In this paper, we study the stability of an inverse scattering problem with far-field data generated by one incident plane wave at a fixed frequency. We assume that the potential is a radial function. It is proved that the unknown potential can be uniquely determined by the far-field data. Within regular class of potential we establish a stability estimate.

In this paper, we establish some generalized Hermite–Hadamard type inequalities for products of two co-ordinated convex functions by using generalized fractional integrals. The inequalities obtained in this study provide generalizations of some result given in earlier works.

In this paper, we study several Diophantine equations, like the one involved in Last Fermat’s Theorem and Beal’s equation, over the rings of polynomials and formal power series with coefficients on characteristic zero unique factorization domains. Moreover, we give general estimates of their number of polynomial solutions. Moreover, we study (non)extensions of Fermat’s little theorem and the (non)existence of Wieferich primes over the univariate formal power series ring with real coefficients.

In this work, we present a new model of a compact stellar object assuming the Vaidya–Tikekar ansatz. The interior matter distribution obeys a color-flavor locked (CFL) equation of state. The interior spacetime is matched smoothly to the vacuum Schwarzschild solution. Using current observational data of the pulsar 4U1608, we show that our model represents a physically viable compact star. Additionally, we present graphical depictions of the variations in mass and radius with central density. Considering the star as a slowly rotating object, we also plot the moment of inertia and the rotation period against the star’s mass.