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- MakaleAçık Erişim2026Scopus SJRQ1GLOBAL BOUNDEDNESS IN A CHEMOTAXIS MODEL WITH SIGNAL-DEPENDENT MOTILITY AND LOGISTIC SOURCE WITH VARIABLE COEFFICIENTS
Ayazoglu, Rabil; Simsek, Ramazan
This paper deals with the following parabolic-parabolic chemotaxis system with growth source { u _ t = ∇· (γ (ε) ∇ u) - ∇· (χ (ε) u ∇v) + η (x) u - μ (x) u ^ α, x ∈Ω, t > 0,; v _ t = Δ v - v + u ^ β, x ∈Ω, t > 0, ]. under homogeneous Neumann boundary conditions in a smooth bounded domain Ω⊂ℝ^N (N≥ 2), and the parameters β >0, α >1, and γ ,χ are positive motility functions. Moreover, we assume that η (x) ^ m + α - 1/α - 1/(μ (x) - μ_ *) ^ m/α - 1 is integrable for some m ≥ 1, where η(·) and μ(·) are positive measurable functions satisfying μ(x) > μ_* > 0 for almost every x ∈Ω. Under these conditions, if α > max{2β, 2}, then the system possesses a unique global bounded classical solution.
- MakaleAçık Erişim2025Scopus SJRQ2Multi-sensor data fusion based on the similarity measure and belief (Deng) entropy under neutrosophic evidence sets
Köseoğlu, Ali; Şahin, Rıdvan; Demir, Ümit
The Dempster–Shafer evidence theory is a very practical concept for handling uncertain information. The foundation of this theory lies in the basic probability assignment (BPA), which exclusively accounts for the degree of support attributed to focal elements (FEs). In this study, neutrosophic evidence sets (NESs) are defined to introduce additional probabilistic measures, aimed at addressing the uncertainty, imprecision, incompleteness, and inconsistency present in real-world information. The basic element of NESs is a neutrosophic basic probability assignment (NBPA), which consists of three components. The truth degree of FEs is represented by the first BPA, the second BPA represents the indeterminacy degree of FEs, and the last BPA characterizes the falsity degree of FEs. In NESs, each support degree of FEs is shown separately without any limitation. Therefore, the general concept of NESs is broader compared to traditional evidence sets and intuitionistic fuzzy evidence sets. Unlike the neutrosophic set (NS), the NBPA method assigns truth-support, uncertainty-support, and false-support degrees, as well as these support degrees, to single and multiple subsets in a discriminative framework. This paper aimed to develop some information measures for NESs, such as neutrosophic Deng entropy (NDE), neutrosophic cosine similarity measure, and neutrosophic Jousselme distance. Then, an improved method based on NDE and neutrosophic cosine similarity measure was established to combine contradictory evidence to increase the influence of reliable evidence on the one hand and to reduce the influence of unreliable evidence on the other hand. Finally, a case involving sensor data integration for target identification was studied to highlight the importance of these innovative ideas. The numerical example demonstrates that the proposed method provides more reliable and superior fusion performance compared to classical models, particularly in scenarios involving high conflict and uncertain information. However, the effectiveness of the method is partially influenced by the structure of the similarity matrix and the entropy parameters, which necessitates careful parameter tuning to achieve optimal results. These limitations are explicitly highlighted to serve as a guide for future improvements and broader applications of the method.
AtıfScopus1WoS1OpenAlex2
İncele - MakaleAçık Erişim2025Scopus SJRQ2A new approach to solving local fractional Riccati differential equations using the Adomian-Elzaki method
Aydemir, Hilal; Merdan, Mehmet; Demir, Ümit
The Elzaki-Adomian decomposition method (EADM) is intended to serve as an efficient analytical method for the resolution of these original fractional-order Riccati differential equations. This can be accomplished permanently by incorporating the Adomian decomposition method with Elzaki. The local fractional derivative is implemented in this format. Particularly in the context of nonlinear differential equations (ODE), this approach is preferred over digital gaps. Additionally, the method’s convergence. Random individuals with uniform, beta, normal, and gamma distributions are used to select the initial conditions or coefficients of the equations. The variance, confidence interval, and expected value of the solutions that are obtained will be determined. MATLAB (2013a) package software will be employed to display the individuals that were brought together, and the results will be analyzed randomly.
AtıfScopus1WoS1OpenAlex2İncele - MakaleYayıncıda açık erişim2024Scopus SJRQ1DYNAMICS IN A PARABOLIC-ELLIPTIC CHEMOTAXIS SYSTEM WITH LOGISTIC SOURCE INVOLVING EXPONENTS DEPENDING ON THE SPATIAL VARIABLES
Ayazoglu, Rabil; Kadakal, Mahir; Akkoyunlu, Ebubekir
We consider the parabolic-elliptic chemotaxis system with the exponents depending on the spatial variables logistic source and nonlinear signal production: ut = ∆u−χ∇·(u∇υ)+f(x, u), (x, t) ∈ Ω×(0, T), 0 = ∆υ−υ+uγ in a bounded domain Ω ⊂ RN (N ≥ 1) with smooth boundary, subject to nonnegative initial data and homogeneous Neumann boundary conditions, where χ > 0, γ ≥ 1 and ∂ν∂ denotes the outward normal derivative on ∂Ω. The logistic function f fulfilling f(x, s) ≤ ηs− µsα(x)+1, η ≥ 0, µ > 0 for all s > 0 with f(x, 0) ≥ 0 ∀x ∈ Ω, where α : Ω → [1, ∞) is a measurable function. It is proved that if 1 ≤ α(x) < ∞ for all x ∈ Ω such that essinfx∈Ω α(x) > γ or essinfx∈Ω α(x) = γ with µ > χ, then there exists a nonnegative classical solution (u, υ) that is global-in-time and bounded. In addition, under the particular conditions γ = 1 and f(x, s) = µ(s − sα(x)+1), if µ is sufficiently large, the global bounded solution (u, υ) satisfies ∥u(·, t) − 1∥L∞(Ω) + ∥υ (·, t) − 1∥L∞(Ω) ≤ Ce− Nk+2 t for all t > 0 with k = min n χ42 12o , C > 0. The global-in-time existence and uniform-in-time boundedness of solutions are established under specific parameter conditions, which improves the known results.
AtıfScopus11WoS9OpenAlex11İncele - DergiDiscrete and Continuous Dynamical Systems - Series B
- DergiAIMS Mathematics