Scopus İndeksli Yayınlar Koleksiyonu
Permanent URI for this collectionhttps://hdl.handle.net/20.500.12416/8651
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Article CFD and DEM Analysis of Cyclone Separator Performance: Implications of Cylinder-to Ratios for Sustainable Engineering(Springer Heidelberg, 2025) Ayli, Ece; Kocak, EyupThis research addresses a common industrial challenge: efficiently separating particles from gas using cyclone separators, a critical component for various applications in sustainable engineering. While several studies have focused on airflow within these separators, this research introduces a novel approach by combining two advanced simulation methods (CFD and DEM) to analyze how different cone heights in a cyclone separator impact its performance. This combined methodology enables the examination of particle movement within the separator, a critical aspect often overlooked in previous studies. By visualizing particle dynamics and analyzing them with DEM, the research underscores the importance of considering particle behavior for obtaining accurate results. Overall, this study enhances our understanding of cyclone separators through state-of-the-art simulations and empirical testing. By elucidating the complex airflow and the influence of geometric design on performance, practical recommendations are provided for the development of more efficient cyclone separators. These improvements can lead to enhanced particle separation and reduced energy consumption, offering significant benefits across multiple industries. The findings reveal that as the conical height-to-total height ratio (h/hc) increases, indicating a more pointed cone, there is a substantial increase in efficiency alongside a minimal and tolerable rise in pressure drop. For instance, at a velocity of 25 m/s, increasing the h/hc ratio from 0.33 to 3 results in a 0.7% reduction in pressure drop and a 14% efficiency increase, contributing to more sustainable operational practices.Article Citation - WoS: 2Citation - Scopus: 2Machine Learning-Driven Approach for Reducing Tool Wear in Die-Sinking Electrical Discharge Machining(Springer Heidelberg, 2025) Cogun, Can; Ayli, EceThis study examines the use of machine learning (ML) techniques to optimize the basic machining parameters and protrusion dimensions that affect tool shape degeneration in die-sinking electric discharge machining (EDM). The primary objective is to decrease errors and enhance prediction and optimization effectiveness. This study introduces a completely novel tool geometry model aimed at minimizing tool shape degeneration, which, to our knowledge, has not been previously documented in the literature. Additionally, this research represents the first instance of employing ML techniques to generate data for addressing this specific type of problem, further advancing the field of die-sinking EDM. The pivotal machining parameters include discharge current, pulse time and machining depth. Three ML approaches are implemented in this investigation: Artificial Neural Network (ANN), Adaptive-Network-Based Fuzzy Inference System (ANFIS), and Support Vector Machine (SVM). In comparison with experimental outcomes, the ANN technique exhibited superior predictive ability with an coefficient of determination (R2) of 0.99985 and an Mean Relative Error (MRE) of 0.854%. Four distinct EDM machining scenarios are presented and machining parameters and protrusion dimensions are optimized using the ANN technique to decrease tool shape degeneration. Optimizing the machining parameters and diagonal dimensions of the protrusion substantially reduced tool shape degeneration. This research demonstrates the effectiveness of ANN in optimizing machining parameters and improving tool performance in die-sinking EDM. A significant reduction in total wear area of 66.7% was achieved with a considerably lower time cost through the optimized ANN network. While the study demonstrates promising results, its reliance on specific datasets for training may limit the generalizability of the model to broader machining scenarios.Article Citation - WoS: 2Citation - Scopus: 2Optical Characterization of Nabi(Moo4)2 Crystal by Spectroscopic Ellipsometry(Springer Heidelberg, 2024) Guler, I.; Isik, M.; Gasanly, N. M.The compound NaBi(MoO4)(2) has garnered significant interest in optoelectronic fields. This study employs spectroscopic ellipsometry to thoroughly examine the linear and nonlinear optical characteristics of NaBi(MoO4)(2) crystals, offering detailed insights into their optical behavior. Our investigation presents a precise method for discerning the crystal's spectral features, revealing the spectral variations of key optical parameters such as refractive index, extinction coefficient, dielectric function, and absorption coefficient within the 1.2-5.0 eV range. Through analysis, we determined optical attributes including bandgap energy, critical point energy, and single oscillator parameters. Additionally, we explored the nonlinear optical properties of NaBi(MoO4)(2), unveiling potential applications such as optoelectronic devices, frequency conversion, and optical sensors. This study enhances comprehension of optical properties of NaBi(MoO4)(2), underscoring its significance in future optical and electronic advancements.Article Citation - WoS: 10Citation - Scopus: 12Regularization of the Inverse Problem for Time Fractional Pseudo-Parabolic Equation With Non-Local in Time Conditions(Springer Heidelberg, 2022) Le Dinh Long; Anh Tuan Nguyen; Baleanu, Dumitru; Nguyen Duc Phuong; Long, Le Dinh; Phuong, Nguyen Duc; Nguyen, Anh TuanThis paper is devoted to identifying an unknown source for a time-fractional diffusion equation in a general bounded domain. First, we prove the problem is non-well posed and the stability of the source function. Second, by using the Modified Fractional Landweber method, we present regularization solutions and show the convergence rate between regularization solutions and sought solution are given under a priori and a posteriori choice rules of the regularization parameter, respectively. Finally, we present an illustrative numerical example to test the results of our theory.Article Citation - WoS: 5Citation - Scopus: 7Ranking Surgical Skills Using an Attention-Enhanced Siamese Network With Piecewise Aggregated Kinematic Data(Springer Heidelberg, 2022) Gilgien, Matthias; Ozdemir, Suat; Ogul, Burcin BuketPurpose Surgical skill assessment using computerized methods is considered to be a promising direction in objective performance evaluation and expert training. In a typical architecture for computerized skill assessment, a classification system is asked to assign a query action to a predefined category that determines the surgical skill level. Since such systems are still trained by manual, potentially inconsistent annotations, an attempt to categorize the skill level can be biased by potentially scarce or skew training data. Methods We approach the skill assessment problem as a pairwise ranking task where we compare two input actions to identify better surgical performance. We propose a model that takes two kinematic motion data acquired from robot-assisted surgery sensors and report the probability of a query sample having a better skill than a reference one. The model is an attention-enhanced Siamese Long Short-Term Memory Network fed by piecewise aggregate approximation of kinematic data. Results The proposed model can achieve higher accuracy than existing models for pairwise ranking in a common dataset. It can also outperform existing regression models when applied in their experimental setup. The model is further shown to be accurate in individual progress monitoring with a new dataset, which will serve as a strong baseline. Conclusion This relative assessment approach may overcome the limitations of having consistent annotations to define skill levels and provide a more interpretable means for objective skill assessment. Moreover, the model allows monitoring the skill development of individuals by comparing two activities at different time points.Article Citation - WoS: 14Citation - Scopus: 17On (2+1)-Dimensional Physical Models Endowed With Decoupled Spatial and Temporal Memory Indices<sup>☆</Sup>(Springer Heidelberg, 2019) Alquran, Marwan; Yousef, Feras; Momani, Shaher; Baleanu, Dumitru; Jaradat, Imad.The current work concerns the development of an analytical scheme to handle (2 + 1) -dimensional partial differential equations endowed with decoupled spatial and temporal fractional derivatives (abbreviated by (alpha,beta) -models). For this purpose, a new bivariate fractional power series expansion has been integrated with the differential transform scheme. The mechanism of the submitted scheme depends mainly on converting the (alpha,beta) -model to a recurrence-differential equation that can be easily solved by virtue of an iterative procedure. This, in turn, reduces the computational cost of the Taylor power series method and consequently introduces a significant refinement for solving such hybrid models. To elucidate the novelty and efficiency of the proposed scheme, several (alpha,beta) -models are solved and the presence of remnant memory, due to the fractional derivatives, is graphically illustrated.Article Citation - WoS: 5Citation - Scopus: 9Numerical Study of Heat Transfer in a Microchannel Equipped With the Semicircular Ribs Influenced by Slip Condition: Effects of Various Slip Coefficient and Hartmann Number(Springer Heidelberg, 2022) Alderremy, A. A.; Aly, Shaban; Tlili, Iskander; Ghaemi, Ferial; Baleanu, Dumitru; He, XinlinIn the present work, a microchannel that benefits from the simultaneous effect of slip condition and semicircular ribs was studied to boost heat transfer. A numerical method was utilized to examine the thermal and hydraulic behavior. The results reveal that the velocity is not zero since the slip condition exists in the microchannel. Furthermore, the velocity near the wall has a dramatic value when the slip length increases. Although the heat transfer is not remarkable by semicircular ribs, the magnetic field plays a vital role in boosting the heat transfer as a result of the declining thermal boundary layer. The effect of magnetic field on the heat transfer on the low Re number is not like the higher one which means as the Reynolds number (Re) varies from 10 to 90, the heat transfer goes up from 1.12 to 2.63. Furthermore, at Re = 90, a 255% enhancement is seen in the microchannel by affecting magnetic field at Hartmann number = 15. The results of slip condition claim that slip condition is introduced as the third most effective factor in rising and improving the efficiency of the microchannel. There is a 16.23% improvement in heat transfer by using slip condition in the microchannel. More importantly, the figure for heat transfer is enhanced by increasing the radius of ribs.Article Citation - WoS: 81Citation - Scopus: 83The (2+1)-Dimensional Heisenberg Ferromagnetic Spin Chain Equation: Its Solitons and Jacobi Elliptic Function Solutions(Springer Heidelberg, 2021) Salahshour, Soheil; Mirzazadeh, Mohammad; Ahmadian, Ali; Baleanu, Dumitru; Khoshrang, Arian; Hosseini, KamyarThe search for exact solutions of nonlinear evolution models with different wave structures has achieved significant attention in recent decades. The present paper studies a nonlinear (2+1)-dimensional evolution model describing the propagation of nonlinear waves in Heisenberg ferromagnetic spin chain system. The intended aim is carried out by considering a specific transformation and adopting a modified version of the Jacobi elliptic expansion method. As a result, a number of solitons and Jacobi elliptic function solutions to the Heisenberg ferromagnetic spin chain equation are formally derived. Several three-dimensional plots are presented to demonstrate the dynamical features of the bright and dark soliton solutions.Article Citation - WoS: 6Citation - Scopus: 6Estimation of Critical Submergence at Single Horizontal Intakes Under Asymmetric Flow Conditions(Springer Heidelberg, 2022) Haspolat, Emre; Gogus, MustafaAir-entraining vortices are one of the serious hydraulic phenomena which can create various problems during the operation of intakes. Generally, air-entraining vortices start to form when the intake submergence is insufficient and less than a critical value. The purpose of the present study is to investigate the formation of air-entraining vortices and determine the critical submergences at single horizontal intake under asymmetrical approach flow conditions by conducting experiments with four different pipe diameters. In the experiments, various sidewall clearances with a series of discharges were tested for a given pipe diameter to examine the effect of dimensionless flow and geometric parameters on the critical submergence. Based on dimensional analysis, empirical equations were derived to predict critical submergence by performing regression analyses of relevant dimensionless parameters. Scale effect analysis was also carried out to investigate the effect of neglected flow parameters on the critical submergence in the application of model similitude law. A formula that makes it possible to transform model results into prototype results in the range of tested parameters was derived and compared with similar studies mostly based on existing installations. Eventually, it was pointed out that the result of the model study underestimates critical submergence compared to others due to the scale effects. Moreover, it was determined that critical submergences at intakes having asymmetrical approach flow conditions are higher than those of symmetrical approach flows.Article Diffraction in Time of Matter Waves Located in a Confined Region(Springer Heidelberg, 2022) Umul, Yusuf Z.The process of diffraction in time of a standing matter wave is studied. This case occurs generally when a quantum particle is confined in a trap or infinite potential well. First of all, the wave-function of a classical time diffracted matter wave is studied by considering a separation of the Fresnel function in terms of geometrical optics and diffracted waves. The behavior of the matter wave which is the counterpart of a geometrical optics field is investigated. Then a confined particle in a one-dimensional infinite potential well is taken into account. One of the walls of the trap is remained at an initial time and the process of diffraction in time is formulated by using the information, obtained from the geometrical optics fields. Some numerical results are given. This paper proposes two original approaches. The first one is the application of the optical diffraction theory to quantum physics. This is the separation of the scattered field into geometric optics and diffracted wave components. The second novelty is the addition of the effects of both of the traveling waves, which compose the standing wave, to the scattering integral.