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Conference Object Effect of Tool Cavity Conditions on Damping, Chatter Mitigation, and Surface Quality in Internally Cooled Milling Tools(Elsevier B.V., 2025) Namlu, R.H.; Dogan, H.; Ozsoy, M.Chatter is a critical factor limiting productivity and efficiency in machining processes. Cutting tools significantly impact chatter stability, as they often serve as the most flexible component. The influence of cutting tools on chatter varies depending on their design and cooling mechanisms. Internally cooled cutting tools, commonly used in industrial applications, have the potential to exhibit distinct damping characteristics due to the presence of internal cavities, differentiating them from conventional solid tools. This study explores the effects of internally cooled milling cutting comparing an empty cavity cutting tool with a tool filled with viscous fluid. The primary objective is to evaluate how these conditions influence the damping of the machining system and their subsequent impact on surface quality, a key outcome sensitive to chatter. Surface topography and roughness measurements were taken after the experiments to assess changes in surface quality. The findings offer valuable insights into the role of internal cooling and fluid properties in not only chatter but also vibration suppressions in milling operations, highlighting their potential to enhance machining performance. © 2025 The Author(s).Article Robust Divergence-Based Tests of Hypotheses for Simple Step-Stress Accelerated Life-Testing Under Gamma Lifetime Distributions(Elsevier B.V., 2026) Balakrishnan, N.; Jaenada, M.; Pardo, L.Many modern devices are highly reliable, with long lifetimes before their failure. Conducting reliability tests under actual use conditions may require therefore impractically long experimental times to gather sufficient data for developing accurate inference. To address this, Accelerated Life Tests (ALTs) are often used in industrial experiments to induce product degradation and eventual failure more quickly by increasing certain environmental stress factors. Data collected under such increased stress conditions are analyzed, and results are then extrapolated to normal operating conditions. These tests typically involve a small number of devices and so pose significant challenges, such as interval-censoring. As a result, the outcomes are particularly sensitive to outliers in the data. Additionally, a comprehensive analysis requires more than just point estimation; inferential methods such as confidence intervals and hypothesis testing are essential to fully assess the reliability behaviour of the product. This paper presents robust statistical methods based on minimum divergence estimators for analyzing ALT data of highly reliable devices under step-stress conditions and Gamma lifetime distributions. Robust test statistics generalizing the Rao test and divergence-based tests for testing linear null hypothesis are then developed. These hypotheses include in particular tests for the significance of the identified stress factors and for the validity of the assumption of exponential lifetimes. © 2026Article Citation - WoS: 6Citation - Scopus: 7Polyethyleneimine Functionalized Waste Tissue Paper@waste PET Composite for the Effective Adsorption and Filtration of Organic Dyes From Wastewater(Elsevier B.V., 2025) Radoor, Sabarish; Karayil, Jasila; Devrim, Yilser; Kim, HernThis study explores the potential of repurposing discarded plastic bottles and cellulosic paper waste to develop cost-effective and high-performance composites for dye removal applications. A novel composite, polyethyleneimine (PEI)-functionalized waste tissue integrated into waste polyethylene terephthalate (wPET) (PEIWT/wPET), was designed as an environmentally friendly adsorbent for wastewater treatment. Successful surface functionalization with PEI was confirmed through FTIR, EDX, and XPS analyses. The PEI-modified composite exhibited enhanced mechanical and thermal stability while demonstrating significantly improved dye adsorption/filtration performance. The composite was evaluated for the removal of both cationic (crystal violet, CV) and anionic (orange II, O II) dyes under optimized conditions; (10,000 mg/L and 1666 mg/L) adsorbent dosage, (11 and 1) pH, 10 mg/L initial dye concentration, and (180 min and 120 min) contact time for CV and O II respectively. Experimental results showed that PEIWT/wPET achieved maximum adsorption capacities of 3.94 mg/g for CV and 11.73 mg/g for O II, approximately five times higher than the unmodified composite (0.74 and 2.4 mg/g). Adsorption isotherm and kinetic studies indicated that the data aligned well with the Langmuir as well as Freundlich and pseudo-second order models. The membrane also exhibited filtration capability for both dyes, achieving a filtration efficiency of 78.69 % for anionic and 41.31 % for cationic dye separation. Overall, the PEIWT/wPET composite offers a promising, sustainable, and energy-efficient solution for the removal of organic pollutants.Article Fröbenius Expansions for Second-Order Random Differential Equations: Stochastic Analysis and Applications to Lindley-Type Damping Models(Elsevier B.V., 2026) Halim, H.; Kerker, M.A.; Boduroğlu, E.This 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.Conference Object AI Trustworthiness and Student Pilots: Exploring Attitudes, Anxieties, and Adaptation Performance(Elsevier B.V., 2025) Ceken, S.; Yilmaz, A.A.; Acar, A.B.This research explores the attitudes of student pilots toward artificial intelligence (AI) applications within the aviation sector, with a focus on their adaptation processes and potential challenges. The recent release of the "EASA AI Roadmap 2.0"by the European Union Aviation Safety Agency (EASA) underscores the growing impact of AI on aviation, driving the emergence of new business models and emphasizing a human-centric approach to AI integration within the aviation industry. This study addresses a significant gap in the literature by examining student pilots' perspectives on AI, specifically focusing on AI trustworthiness, attitudes, anxieties, and adaptation performance. The study utilizes a quantitative research approach, collecting data from 150 student pilots through surveys. Preliminary results from 106 respondents indicate varied attitudes toward AI, with significant implications for AI-supported cockpit assistant systems and the broader aviation industry. The study sample consisted of 106 (Mage = 23.6, SDage= 4.64; 79% male) student pilots from of university pilot training departments and various flight school in Turkey. Collected data were analyzed on SPSS 29. The study revealed that Sociotechnical Blindness AI anxiety is a significant predictor of general attitudes toward AI among student pilots. This finding suggests that higher levels of anxiety related to the perceived complexity and potential unintended consequences of AI are associated with more positive general attitudes toward AI. The findings emphasize the need for a human-centric approach to AI integration, highlighting the importance of trust, transparency, and adaptive training in the successful adoption of AI technologies in aviation. © 2024 The Authors. Published by ELSEVIER B.V.Article Citation - Scopus: 2A Solution To Adhesion Problem of Oxide Thin Films on Zinc Selenide Optical Substrates(Elsevier B.V., 2017) Cosar,M.B.; Aydogdu,G.H.; Batman,H.; Ozhan,A.E.S.Zinc Selenide optical substrates have high transparency within the 0.5 to 14.0 μm wavelength range. This makes them an attractive candidate for multi band imaging applications in the optical components. In order to minimize reflection losses for visible, near-infrared and mid-infrared applications, Zinc Selenide lens are coated with multi-layered oxide thin films by physical vapor deposition method or Ion Beam Deposition. In this study, four-layer dual beam anti-reflective coating design at 1.064 μm and between 3.6 and 4.9 μm is applied using Ion Beam Deposition system directly on Zinc Selenide substrates. Because of solving the adhesion problem which is observed after the coating of oxides on Zinc Selenide substrates, they were treated at 300 °C for varying amounts of time before coating oxides. Treated samples were examined in terms of their roughness, contact angle, morphology, refractive index, transparency, crystallography and chemical composition. It is found that it is possible to manufacture durable oxide thin film coatings on Zinc Selenide, utilizing well designed pre-treatment processes. © 2016 Elsevier B.V.Conference Object Citation - Scopus: 1Enhancing Sustainable Machining of Inconel 718 Using Multi-Walled Carbon Nanotubes and TiO2based Nanofluid Minimum Quantity Lubrication(Elsevier B.V., 2025) Namlu, Ramazan Hakkı; Kaftanoĝlu, BılgınInconel 718 is extensively utilized especially in the aerospace sector due to its outstanding resistance to creep and corrosion, along with its capability to maintain strength at high temperatures. However, its high work hardening rate and low thermal conductivity present significant challenges in machining processes, including the need for extensive use of coolants, shortened tool life, and the necessity for post-processing operations for adequate surface quality, all of which hinder sustainable manufacturing. To address these issues, an innovative cooling/lubrication method, Nanofluid Minimum Quantity Lubrication (NMQL), aims to enhance the sustainable machining of Inconel 718 by minimizing these problems. NMQL involves the aerosolized delivery of nanoparticle-enriched nanofluid oil with compressed air to the cutting zone. In this way, NMQL utilizes the nanoparticles' cooling and lubrication abilities, resulting in lower cutting forces, reduced surface roughness, and decreased tool wear compared to other cooling/lubrication conditions, thereby improving machining performance. This study compares the performance of NMQL in terms of cutting forces, surface roughness and topography, and subsurface microhardness, using Multi-Walled Carbon Nanotubes (MWCNT) and TiO2nanoparticles, with Conventional Cutting Fluids (CCF), aiming to achieve more sustainable machining of Inconel 718. Also, a sustainability assessment was done using Pugh Matrix Approach in order to find the most sustainable cooling option. © 2025 Elsevier B.V., All rights reserved.Article Citation - Scopus: 6A Generalization of the Meir–keeler Type Contraction(Elsevier B.V., 2012) Chi,K.P.; Karapinar,E.; Thanh,T.D.In this paper, we prove a fixed point theorem which has applications on maps called T-contractions which include a class that satisfies the Meir–Keeler type contractive condition. We also present an example that illustrates that T-contractions are a natural extension of the Meir–Keeler type contraction. © 2012Editorial Special Issue: Computational Methods in System Reliability(Elsevier B.V., 2024) Tank F., Professor,; Eryilmaz S., Professor,[No abstract available]Article The Effect of Two Different Types of Daily Disposable Monofocal Contact Lenses on Ocular Wavefront Aberrations(Elsevier B.V., 2025) Yakar, K.Background: To compare the effect of two daily disposable soft contact lenses on ocular wavefront aberrations. Methods: This study included 34 eyes from 17 patients aged 18 to 40 years (mean age: 27.12±8.3 years) with identical myopic refractive errors in both eyes without astigmatism and requesting contact lens use. Initially, wavefront aberrations; total, tilt, high, total coma, total trefoil, total 4.foil, sphere, high astigmatism, RMS (3 mm/5 mm) were measured using Nidek OPD Scan II aberrometer/topograph in both eyes without contact lenses. Acuvue Oasys with HydraLuxe 1-Day (senofilcon A) daily disposable contact lenses were applied to the right eye, while Precision 1 (verofilcon A) daily disposable contact lenses were applied to the left eye based on refractive errors. Wavefront aberration measurements were repeated 60 min later with contact lenses, and aberrations were compared to baseline and fellow eyes' measurements. The magnitudes of aberration changes after contact lens application were analyzed. Results: Both types of daily disposable contact lenses reduced total wavefront aberrations. Acuvue Oasys with HydraLuxe 1-Day contact lenses showed a significant increase in total trefoil aberration (p = 0.048). Precision 1 contact lenses showed a significant increase (p = 0.034) only in total tilt aberrations compared to baseline. No significant differences were found between the lenses regarding changes in all wavefront aberrations. Conclusion: Both daily disposable lenses effectively reduced total wavefront aberrations, though they increased certain subtypes of high-order aberrations in young adult myopes. © 2025 The Author(s). Published by Elsevier B.V. This is an open access article under the CC BY-NC license. http://creativecommons.org/licenses/by-nc/4.0/
