AppliedMath, Volume 6, Issue 8

A Lyapunov-based framework for stability analysis and synthesis of adaptive neural-network (NN) controllers for a class of uncertain second-order nonlinear systems (SNS) with bounded external perturbations and unmodelled dynamics is presented. Online...

Meningitis is a significant public health problem despite the availability of effective vaccination programs, especially in children and young people. The memory-dependent features of disease transmission, immunity and vaccination dynamics are not of...

SPARQ is an advanced global optimization algorithm, the direct evolution of an earlier method called ARQ2. It searches efficiently for the best solution to problems where the space of options is too vast to check exhaustively, such as tuning antenna...

This paper presents a new algorithm based on splitting methods for the numerical solution of the Navier–Stokes equations coupled with the heat equation. This work is set in a context where viscosity and thermal conductivity depend explicitly on...

Electron–positron pair production is one of the fundamental quantum electrodynamical (QED) processes and provides an important framework for investigating photon–matter interactions. In this work, the influence of linear photon polarizati...

We study a delayed semilinear evolution equation with a Caputo time derivative and the spectral fractional Dirichlet Laplacian on a bounded connected domain. The model separates two forms of memory: the Caputo operator retains the distributed Volterr...

Missing data remain a major challenge in breast cancer research because they can introduce bias, reduce statistical efficiency, and compromise the performance of predictive models. Although numerous imputation techniques have been proposed, their com...

Suppose that T is a normal spanning tree (depth-first search tree) of a graph G. If $e=xy$ and $e^{\prime }=uv$ are edges of G, satisfying $x{\prec }_{T}u{\prec }_{T}y{\prec }_{T}v$, then they are called secant edges of G with respect to T. Suppose that G has no secant e...

Financial contagion—the propagation of shocks across markets, sectors, and time—remains one of the central questions in empirical finance, and yet most computational approaches model it at the wrong granularity. Existing work captures con...

Task-evoked EEG can reveal individual differences in cognitive processing, but it also creates a machine-learning challenge: many epochs are recorded from relatively few participants, and evaluation can be misleading if within-subject dependence is i...

This study obtained the energy levels and examined the partition function (Z) of a quantum system described by an Eckart-like potential model. By adopting the Greene–Aldrich approximation scheme for the centrifugal term, the radial Schrödi...

We introduce finite-observation conditional guarded language operators on the complete length-based ultrametric space of formal languages over a finite alphabet. A finite observation map selects a guarded branch according to the membership of prescri...

The Rayleigh–Logarithmic distribution provides a useful framework for modelling lifetime data by combining continuous lifetime variability with a logarithmic compounding mechanism. This study introduces a three-parameter Alpha Power Rayleigh&nd...

Fractional Brownian motion (fBm) provides a powerful stochastic framework for modeling long-range temporal dependence that cannot be represented by classical Brownian motion. This study presents a numerical and theoretical investigation of constraine...

We study a Camassa–Holm-type equation with a prescribed, time-independent bottom profile, $m_t+(u+h\left(x\right))m_x+2u_{x}m+{\displaystyle \frac{1}{2}}{h}_x\left(x\right)m=0,m=(1-{\partial }_x^2)u.$ The model is considered here as a mathematically motivated bottom-modified Camassa–Holm equatio...

Complex interval-valued fuzzy sets are powerful tools for representing uncertainty and periodicity that occur in many real-life problems. They not only take both periodicity semantics and uncertainty into account but also describe the information usi...

Acetaldehyde is routinely monitored in neutral alcohol, but pooled precision summaries can obscure changes in performance across the working range. This study evaluated 446 valid GC–FID verification results obtained by three anonymized analysts...

This paper establishes new Fejér and Hermite–Hadamard-type inequalities for functions of two variables whose mixed second-order partial derivatives satisfy coordinated GA-convexity or coordinated GA-quasi-convexity on a rectangle in the...

In this study, we propose a mathematical model for the dynamics of atmospheric carbon dioxide (CO₂) with human population growth and an age-structured vehicle population. The positivity and boundedness of the model’s solutions are verified, and...

This study investigates the efficacy of early multimodal data fusion for identifying academic performance profiles and predicting academic risk in specialized postgraduate education under small-sample constraints ($n=51$ graduate students distributed a...

External sulfate attack constitutes a major durability challenge for structural concrete, yet the influence of mechanical loads on sulfate transport remains incompletely understood. This study develops a coupled sulfate–water transport model th...

This paper studies symmetrized neural network (SNN) operators generated by an adjustable half-hyperbolic tangent activation function. The construction is based on the paired density kernels ${\aleph }_t$ and ${\aleph }_{1/t}$, whose average defines the symme...