Atılım Academic Archive (Atılım University)
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Sustainable Stabilization of Expansive Soils Using Waste Marble Powder and Expanded Polystyrene Beads: Experimental Evaluation and Predictive Modelling
No full textExpansive soils exhibit considerable volume changes with moisture fluctuations leading to serious challenges for civil infrastructure, causing structural instability, pavement distortion, and foundation damage. While lime and cement remain widely used stabilizers, recent research has increasingly focused on waste-derived materials such as marble powder (MP) and expanded polystyrene beads (EPSb) as promising alternatives. These materials provide a practical approach to soil stabilization while contributing to the reuse of industrial by-products. In this study, the engineering behavior of high-plasticity clay was improved through the inclusion of MP and EPSb as additive materials. MP was added at 0%, 5%, 10%, 15%, and 20%, and EPSb at 0%, 0.3%, and 0.9% by dry weight of the high plasticity clay. Both additives were used alone and in combination. Laboratory tests, including Standard Proctor, free swell (FS), and unconfined compressive strength (UCS), were conducted. The results confirmed that the additives effectively reduced the liquid limit (LL) by 20.1% and the plasticity index (PI) by up to 22.4%. Results showed that EPSb effectively reduced FS and UCS, while MP decreased FS and increased UCS up to an optimal content. The most effective mixes achieved a maximum reduction of 54.7% in free swell (FS) (at 20% MP and 0.9% EPSb content) and a maximum increase of 13.1% in unconfined compressive strength (UCS) (at 5% MP content) compared to the untreated soil. The compaction tests further revealed a general decrease in optimum moisture content (OMC) and a slight increase in maximum dry density (MDD) with increasing MP content. Accordingly, the free swell (FS) and unconfined compressive strength (UCS) of the treated soils were predicted using multiple linear regression (MLR) and artificial neural network (ANN) models, developed from both the current experimental dataset and previously published studies. Input variables included untreated FS and UCS values, additive percentages, and one index property. The ANN model demonstrated superior predictive capability, achieving R2 values of 0.955 and 0.874 for FS and UCS, respectively, compared to 0.411 and 0.618 obtained with MLR. These results highlight the robustness of ANN in capturing nonlinear soil behavior and underscore its reliability and accuracy, particularly under limited data conditions
On the Image of the Limit Q-Durrmeyer Operator
No full textThe focus of this work is on the properties of the q-Durrmeyer operators Mn,q, n E N, and M infinity,q introduced, for q E (0, 1), by V. Gupta and H. Wang. First, it is shown that, for each f E C[0, 1], the sequence {Mn,q f}nEN converges to M infinity,q f uniformly on [0, 1] with a rate not slower than Cq, fqn, which refines the previously available result by V. Gupta and H. Wang, and implies the possibility of an analytic continuation for M infinity,q f into a neighbourhood of [0, 1]. Further investigation shows that M infinity,q f admits an analytic continuation as an entire function regardless of f E C[0, 1]. Finally, the growth estimates for these functions are received and applied to describe the point spectrum of M infinity,q. The paper also addresses the significant differences between the properties of M infinity,q and the previously (c) 2025 Elsevier Inc. All rights are reserved, including those for text and data mining, AI training, and similar technologies
The Role of Emotional Intelligence in the Relationship Between Burnout and Perceived Quality of Care Among Oncology Nurses
No full textPurpose This study aimed to examine the relationships between burnout, emotional intelligence, and perceived caring behaviours among oncology nurses and to assess the predictive and mediating roles of these variables in explaining caring behaviours. Methods A descriptive, cross-sectional study was conducted with 202 oncology nurses in Türkiye. Data were collected using validated instruments measuring burnout, emotional intelligence, and caring behaviors. Data analysis employed descriptive statistics, Pearson correlation analyses, multiple linear regression, and structural equation modeling. Results Emotional intelligence was positively associated with caring behaviours (r = .359, p < .001) and negatively associated with burnout subdimensions. Caring behaviours were inversely related to emotional exhaustion (r = −.258, p < .001), depersonalisation (r = −.397, p < .001), and reduced personal accomplishment (r = −.214, p = .002). In the regression model (R2 = .214, p < .001), emotional intelligence significantly predicted caring behaviours positively (β = .218, p = .002), while depersonalisation was a significant negative predictor (β = −.288, p < .001). However, emotional intelligence did not mediate the relationship between burnout and caring behaviours (Sobel test p = .332). Conclusion While emotional intelligence was positively associated with caring behaviours and buffered the impact of burnout—particularly depersonalisation—it did not mediate the relationship between burnout and caring. These findings support the value of enhancing emotional intelligence to improve care quality and nurse well-being, though contextual factors may influence its mediating role. © 2026 Elsevier Ltd
Fröbenius Expansions for Second-Order Random Differential Equations: Stochastic Analysis and Applications to Lindley-Type Damping Models
No full textThis paper develops a Frobenius series framework for the stochastic analysis of second–order random differential equations of the form Y¨(t)+A(t)Y˙(t)=0,where the damping coefficient A(t) is a positive stochastic process and the initial conditions are square–integrable random variables. Assuming mean–square analyticity of A(t) in a neighborhood of the initial time, we establish existence and uniqueness of the solution in L2(Ω) and derive exponentially convergent truncation error bounds for the associated Frobenius expansion. The resulting series representation enables the numerical approximation of the probability density function of Y(t) via Monte Carlo simulation. To improve computational efficiency, a control variates strategy is incorporated for variance reduction. A comprehensive numerical study is conducted for a broad family of positive, right–skewed damping distributions, including the Lindley, XLindley, New XLindley (NXLD), Gamma–Lindley, Inverse–Lindley, Truncated–Lindley, Log–Lindley, and a newly proposed Mixed Lindley–Uniform model. The simulations illustrate how different tail behaviors and boundedness properties of the damping coefficient influence the stochastic dynamics and the accuracy of density estimation. Finally, stylized applications to option pricing and Value–at–Risk estimation are presented to illustrate how the Frobenius–based framework and control variates methodology can be embedded within standard uncertainty quantification workflows. Overall, the proposed approach provides a flexible and computationally efficient tool for the analysis of randomly damped dynamical systems. © 2026 Elsevier B.V
A Computationally Efficient Approximation for Fractional Differencing: First-Order Operators
No full textThis paper introduces the First-Order Fractional Differencing (FOFD) operator that substantially reduces the computational burden of fractional differencing for large-scale applications. While the standard Gr & uuml;nwald-Letnikov (GL) operator requires O(T2) operations for a series of length T, and recent FFT-based methods achieve O(T log T), our FOFD operator requires only O(T) operations through a simple two-point recursion. We develop an optimal weight calibration framework that ensures this computational efficiency does not compromise statistical accuracy, deriving a general formula wopt = d & sdot; (1-0.9 rho)beta(p) that adapts to the persistence structure of autoregressive processes. Empirical applications demonstrate substantial improvements: for the Chicago Fed National Financial Conditions Index with extreme persistence (rho= 0.992), optimal weight calibration reduces approximation error by 93% while preserving the autocorrelation structure of the GL operator. For a series of 10,000 observations, our method requires 20,000 operations compared to 530,000 for FFT-based methods and 50 million for standard implementations-enabling fractional differencing in real-time and high-frequency contexts previously infeasible due to computational constraints. The method's simplicity, requiring no specialized libraries and providing direct implementation through our calibration formula, makes it immediately accessible to practitioners while maintaining the long-memory properties essential for financial time series modeling
Catalyst-Free Synthesis of Thiourea-Linked Dumbbell-Shaped POSS for Ultrasensitive Determination of Prilocaine in Human Blood with Computational Insights
No full textAlthough various electrochemical sensors have been reported for the determination of local anesthetic drugs, most existing platforms suffer from limited sensitivity, insufficient surface stability, or inadequate electron-transfer efficiency, particularly when applied to complex biological matrices. Moreover, the potential of hybrid polyhedral oligomeric silsesquioxane (POSS)-based nanostructures combined with metal oxide nanoparticles for improving electroanalytical performance has not yet been thoroughly explored. In this study, a high-sensitivity electrochemical nanosensor was developed for the determination of prilocaine (PC), an amide-type local anesthetic, using a glassy carbon (GC) electrode modified with POSS‑titanium dioxide (TiO2) nanoparticles (Nps). The combination of modifications provided a unique electrode surface by combining the high stability of POSS with the strong adsorption properties of TiO2 Nps, thereby increasing both surface loading and adsorption capacity. To elucidate the structure of the modification combination, 1H and 13C nuclear magnetic resonance (NMR) and Fourier transform infrared (FTIR) spectroscopic techniques, as well as Brunauer–Emmett–Teller (BET), X-Ray diffraction (XRD), Electrochemical impedance spectroscopy (EIS), and high-resolution transmission electron microscopy (HRTEM) analysis techniques were used, respectively. The analytical performance of the developed nanosensor was systematically optimized using differential pulse voltammetry (DPV), adsorptive stripping differential pulse voltammetry (AdSDPV), square wave voltammetry (SWV), and adsorptive stripping square wave voltammetry (AdSSWV) techniques. As a result of the optimization studies, the lowest limit of detection (LOD) was 3.66 × 10−8 M with the AdSSWV technique. DFT results corroborated the mechanism, indicating ring-centered electron donation (HOMO) and adsorption-favored N/O regions (MEP). Low LOD values were also recorded with other techniques, demonstrating the method's high sensitivity in analyte detection. In real sample analysis tests, PC recovery value in human blood samples was determined to be 98.69% using the AdSDPV technique. Despite the matrix effect, the nanosensor demonstrated high accuracy and reproducibility. The results indicate that the developed POSS-TiO2 Nps modified GC electrode sensor offers a high-performance, reliable, and good electrochemical detection platform suitable for use in biological and clinical applications. © 202
Relationship Between Crustal Magnetic Anomalies and Earthquake Activity in Malatya and Surrounding Region After the 2023 Kahramanmaraş Earthquakes, Southeastern Türkiye
No full textThe East Anatolian Fault Zone (EAFZ) is one of the most critical and active tectonic elements in T & uuml;rkiye, and there are a significant number of high-magnitude earthquakes along with the EAFZ, mentioned in the historical documents and recorded in the instrumental periods in southeastern Anatolia. The latest devastating tectonic activity occurred on February 6, 2023 (Mw = 7.7), followed by another high-magnitude earthquake in the same day (Mw = 7.6) on this fault zone. More than 15,000 aftershocks (some of them are Mw >= 4.0) have been recorded since then. The EAFZ is composed of several sub-fault zones and their segments with different elongations. Although the majority of these segments indicate ruptures during the main shock and aftershocks, some of them (including the Malatya Fault) are still aseismic, including great potential to trigger high-magnitude earthquakes. In this study, we interpreted the magnetic data and the epicenter distributions of earthquakes to correlate the tectonic structures and active fault zones. The fault indicators (with maxspots) based on the different types of derivative transformations provided good correlations between the faults and magnetic discontinuities because almost all fault zones in the study area have been filled by the magmatic intrusions to create magnetic anomalies. The maxspots are also another practical tool to determine the possible segments of faults and/or exact locations of undefined magmatic intrusions. It is possible to claim that the faults have provided conduits for the intrusion of the causative bodies while triggering the earthquakes in this critical area. The earthquakes are generally recorded along the southern fault segments. As a result of these methods and correlations, we determined the exact location and the length of the Malatya Fault (approximately 220 km), which is represented with the low-magnitude earthquakes.General Directorate of Mining Research and Exploration (MTA) of Turkey [YDABCAG-118]The authors are grateful to the General Directorate of Mining Research and Exploration (MTA) of Turkey for providing the aeromagnetic data that were used in two projects (a national and another international projects (TUBITAK Project No.: YDABCAG-118 and European Scientific Exchange Program-ESEP during 1997). Authors thank the Editor-in-Chief and Associate Editor for the delicate handling of our submission. Special thanks for two anonymous reviewers for their constructive critiques
Estimation of Parameters for a System Equipped with Protection Block
No full textThis paper studies the problem of estimating unknown parameters involved in a system which is equipped with a protection block. The system has different failure rates depending on whether the protection block is present or not, as the protection block is modeled by its own lifetime distribution and contributes an additional failure component to the system. The model is analyzed under the assumption of exponentially distributed lifetimes, leading to the study of its distributional properties and the estimation problem for its unknown parameters. Closed-form expressions for the maximum likelihood estimators are obtained. Furthermore, theoretical expectations and variances of the estimators are derived. We also discuss the stress-strength reliability estimation problem and construct confidence intervals for the associated reliability measure. Numerical results are provided to demonstrate the implementation of the proposed methods
How Analytic Properties of Functions Influence Their Images Under the Limit q-Stancu Operator
No full textOstrovska, Sofiya/0000-0003-1842-7953; Turan, Mehmet/0000-0002-1718-3902In the study of various q-versions of the Bernstein polynomials, a significant attention is paid to their limit operators. The present work focuses on the impact of the limit q-Stancu operator Sq infinity,alpha on the analytic properties of functions when 0 0. It is shown that for every f is an element of C[0, 1], the function S-q,(alpha infinity)fadmits an analytic continuation into the disk {z : z+alpha/(1-q) < 1+ alpha/(1-q)}. In addition, it is proved that the more derivatives f has at x = 1, the wider this disk becomes. Further, if f is infinitely differentiable at x = 1, then the function S-q,(alpha infinity)fis entire. Finally, some growth estimates for (S-q,(alpha infinity)f)(z) are obtained.Recep Tayyip Erdogan UniversityOpen access funding provided by the Scientific and Technological Research Council of Turkiye (TUBITAK)
On Nonlocal Boundary Caputo Tempered Fractional Coupled Systems in Banach Spaces
No full textWe employ M & ouml;nch's fixed point theorem along with the technique of measure of non-compactness to establish the existence of solutions for a coupled system of tempered fractional differential equations with nonlocal boundary conditions. Additionally, we investigate the Ulam stability of the system as a qualitative aspect of our analysis. Finally, an illustrative example is provided to demonstrate that our approach meets the specific requirements set forth in the paper