Open Journal of Mathematical Analysis (OMA)

The current study focuses on the investigation and develop of a new approach called Hussein–Jassim method (HJM), suggested lately by Hassan et al.; specifically, we investigate its applicability to fractional ordinary delay differential equations in the Caputo fractional sense. Several examples are offered to demonstrate the method’s reliability. The results of this study demonstrate that the proposed method is highly effective and convenient for solving fractional delay differential equations.

We define and study the Stockwell transform \(\mathscr{S}_g\) associated with the Whittaker operator
\[\Delta_{\alpha}:=-\frac{1}{4}\left[x^2\frac{\mbox{d}^2}{\mbox{d}x^2}+(x^{-1}+(3-4\alpha)x)\frac{\mbox{d}}{\mbox{d}x}\right],\]
and prove a Plancherel theorem. Moreover, we define the localization operators \(L_{g,\xi}\) associated to this transform. We study the boundedness and compactness of these operators and establish a trace formula. Finally, we give a Shapiro-type uncertainty inequality for the modified Whittaker-Stockwell transform \(\mathscr{S}_g\).

Consider a unit disk \(\Omega=\{z:|z|<1\}\). A large subset of the set of analytic-univalent functions defined in \(\Omega\) is examined in this exploration. This new set contains various subsets of the Yamaguchi and starlike functions, both of which have profound properties in the well-known set of Bazilevič functions. The Ma-Minda function and a few mathematical concepts, including subordination, set theory, infinite series formation and product combination of certain geometric expressions, are used in the definition of the new set. The estimates for the coefficient bounds, the Fekete-Szegö functional with real and complex parameters, and the Hankel determinants with a real parameter are some of the accomplishments. In general, when some parameters are changed within their interval of declarations, the set reduces to a number of recognized sets.

Let \( u’ + Au = h(u,t) + f(x,t) \) with the initial condition \( u(x,0) = u_0(x) \), where \( u \in H \), \( u’ := u_t := \frac{du}{dt} \), and \( H \) is a Hilbert space. The nonlinear term satisfies the estimate \( \|h(u,t)\| \le a\|u\|^p (1+t)^{-b} \), and the operator \( A \) satisfies the coercivity condition \( (Au,u) \ge \gamma(t)(u,u) \), where \( \gamma(t) = q_0(1+t)^{-q} \). Here, \( a, p, b, q_0, \) and \( q \) are positive constants. Sufficient conditions are established under which the solution exists and is either bounded or tends to zero as \( t \to \infty \).

In this paper, we derive summation formulae for the generalized Legendre-Gould Hopper polynomials (gLeGHP) \({}_SH^{(m)}_n(x,y,z,w)\) and \(\frac{{}_RH^{(m)}_n(x,y,z,w)}{n!}\) by using different analytical means on their respective generating functions. Further, we derive the summation formulae for polynomials related to \({}_SH^{(m)}_n(x,y,z,w)\) and \(\frac{{}_RH^{(m)}_n(x,y,z,w)}{n!}\) as applications of main results. Some concluding remarks are also given.

In this paper, the differential subordination \( \frac{b}{\phi(z)}+ c~ \phi(z) + d~ \frac{z \phi'(z)}{\phi^{k}(z)} \prec s(z), k\geq 1, z\in\mathbb{E}\) is studied by using Lowner Chain. The corresponding result for differential superordination is also obtained to get sandwich type result. Consequently, we obtain sufficient conditions for Starlikeness and Convexity of analytic function \(f\).

The purpose of this paper is to apply the concept of \(log -\)series in order to determine the sum of certain power series, where the n-th terms involves the factorial mapping, the generalized harmonic numbers and the reciprocals of factorial sums.

This paper investigates the geometry and norm-attainability of operators within various operator ideals, with a particular focus on the role of singular values and compactness. We explore the behavior of norm-attainable operators in the context of classical operator ideals, such as trace-class and Hilbert-Schmidt operators, and examine how their geometric and algebraic properties are influenced by membership in these ideals. A key result of this study is the connection between the singular values of trace-class operators and their operator norm, establishing a foundational relationship for understanding norm-attainment. Additionally, we explore the conditions under which weakly compact and compact operators can attain their operator norm, providing further insights into the structural properties that govern norm-attainability in operator theory. The findings contribute to a deeper understanding of the interplay between operator ideals and norm-attainability, with potential applications in functional analysis and related fields.

The primary objective of this paper is to introduce a novel integral transform, referred to as the Hartley-Bessel-Stockwell transform, and to establish several fundamental results associated with it. Specifically, we derive generalized versions of Parseval’s identity, Plancherel’s theorem, the inversion formula, and Calderon’s reproducing formula for this transform. Furthermore, we investigate the concentration properties of the Hartley-Bessel-Stockwell transform on sets of finite measure and present an uncertainty principle for orthonormal sequences. Finally, leveraging the theory of reproducing kernels and best approximation methods, we examine the extremal functions associated with this transform. We provide their integral representations and derive optimal estimates for these functions within weighted Sobolev spaces.

In this research, we utilize the Opoola differential operator to define new subclasses of starlike and convex functions within the unit disk \(U\): \(S^{m,t}_{\beta,\mu}(\alpha,\eta,\gamma)\), \(K^{m,t}_{\beta,\mu}(\alpha,\eta,\gamma)\), \(T^{m,t}_{\beta,\mu}(\alpha,\eta,\gamma)\), and \(C^{m,t}_{\beta,\mu}(\alpha,\eta,\gamma)\), characterized by parameters \(\alpha\), \(\eta\), and \(\gamma\), which denote their order and type. We investigate various geometric properties of these functions, including characterization properties, growth and distortion theorems, arithmetic mean, and radius of convexity. The results obtained generalize many existing findings, forming a foundation for further research in the theory of geometric functions. Additionally, we present several corollaries and remarks to illustrate extensions of our results.