Scopus İndeksli Yayınlar Koleksiyonu / Scopus Indexed Publications Collection

Permanent URI for this collectionhttps://hdl.handle.net/11147/7148

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  • Article
    A Phenomenological Kinetic Flotation Model: Intrinsic Floatability Profiling for Batch and Continuous Flotation Systems
    (Springer Heidelberg, 2026) Polat, Mehmet; Guzel, Veli; Kobas, Muammer; Polat, Hurriyet
    This study presents a mechanistic flotation kinetics model that unifies the description of mineral particle floatability in both batch and continuous systems. Building on a physically explicit interpretation of bubble-particle interactions, the model introduces the concept of intrinsic floatability, \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$${\upphi }_{\text{P},\text{ij}}<^>{\text{s}}$$\end{document}, defined as the size-and composition-dependent probability that a particle within a bubble's sweep volume reports to the froth. A central feature of the framework is that \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$${\upphi }_{\text{P},\text{ij}}<^>{\text{s}}$$\end{document} is decoupled from system-level rate-determining factors, such as bubble-particle encounter frequency, transport limits, and bubble surface crowding-that otherwise confound attempts to extract floatability distributions from kinetic data. This separation is achieved through three explicit, time-dependent parameters: the encounter rate kappa(t), the limiting flotation rate mu(t), and the bubble saturation factor chi(t). Together, these parameters isolate intrinsic particle behavior from external constraints. The model naturally reduces to the classical first-order rate law in dilute pulps, while in concentrated suspensions it predicts systematic deviations, approaching zero-order kinetics as bubble surfaces saturate. Importantly, the same formulation applies seamlessly to batch tests and multi-stage continuous circuits, enabling a consistent theoretical framework across scales and ore types. Requiring only standard flotation data and known system parameters, the model is practical for both laboratory coal flotation studies and industrial non-coal applications. Validation using batch coal data and continuous plant-scale copper flotation results demonstrates its robustness and broad relevance.
  • Article
    Damage Assessment of Structures Following the February 6, 2023 Kahramanmaraş Earthquakes: A Dataset-Based Case Study in Gaziantep, Türkiye
    (Springer Heidelberg, 2025) Atasever, Kurtulus; Aydogdu, Hasan Huseyin; Narlitepe, Furkan; Goksu, Caglar; Demir, Ugur; Demir, Cem; Ilki, Alper
    Following the 2023 Kahramanmara & scedil; Earthquakes (Mw 7.7 and 7.6) that struck T & uuml;rkiye on February 6, 2023, the Ministry of Environment, Urbanization, and Climate Change (MoEUCC) initiated a large-scale post-earthquake damage assessment campaign, targeting more than 2,3 million structures within the affected region. A comprehensive field survey was carried out in and around Gaziantep, one of the most severely affected cities. The authors assessed more than 1700 structures representing a wide range of occupancy types, including residential, educational, healthcare, religious, administrative, industrial, and lodging structures. In this paper, the methodological process of post-earthquake data collection in and around Gaziantep is presented, together with the data on the distribution of damage with respect to construction period, number of stories, and building occupancy type, to ensure a complete understanding of the extent and characteristics of structural damage. The damage assessment employed two data sources: (i) the data gathered through the authors' newly developed, novel damage-assessment software, presented here for the first time, and (ii) the official post-earthquake damage database of the MoEUCC. A further novelty of this study is the presentation of the largest dataset to date for the investigated earthquake doublet, encompassing approximately 1700 buildings. Additionally, the relationship between damage states, peak ground accelerations, and fault distances is thoroughly investigated. The detailed earthquake-hit site investigations revealed that the examined structures displayed structural inadequacies akin to those witnessed in previous seismic events, with a notable focus on the arrangement of the structural system, the quality of construction materials and reinforcement detailing.
  • Article
    A Robust Possibilistic Semi-Supervised Fuzzy Clustering Algorithm With Neighborhood-Aware Feature Weighting
    (Springer Heidelberg, 2025) Moghaddam, Arezou Najafi; Aghazadeh, Nasser; Hashemzadeh, Mahdi; Oskouei, Amin Golzari
    The Semi-Supervised Fuzzy C-Means (SSFCM) method integrates class distribution information with fuzzy logic to overcome the challenges of semi-supervised clustering methods. While the inclusion of label information in the objective function improves the quality of the clustering method, semi-supervised fuzzy techniques still encounter important limitations, including (1) sensitivity to noise and outliers, (2) uniform feature importance, (3) neglecting the influences of neighborhood in the clustering process. In this paper, an improved semi-supervised clustering algorithm is presented to address these challenges. First, the algorithm reduces the sensitivity to noise and outliers by integrating the possibilistic fuzzy C-means algorithm into the SSFCM method. Second, a dynamic feature weighting method assigns different weights to the features in each cluster, which improves the performance of the algorithm in imbalanced datasets. Third, the proposed algorithm introduces a neighborhood mechanism that incorporates the neighbor's trade-off weighting and feature weighting strategy considering a strong metric. Finally, a robust kernel metric is used to further improve the performance on complex and nonlinear datasets. Extensive experiments are conducted on several benchmark datasets to evaluate the performance of the proposed method. The results show that the proposed method outperforms the current state-of-the-art techniques. The implementation source codes of the proposed method are publicly available at https://github.com/Amin-Golzari-Oskouei/RPSSFC-NAFW.
  • Article
    Enhanced Wear Resistance of Epoxy Composites Through the Incorporation of Diatom Frustules: a Multi-Objective Optimization Approach
    (Springer Heidelberg, 2025) Gulturk, E.; Aydin, L.; Sahin, A. E.; Sinmazcelik, T.; Guden, M.
    The present work investigates the enhancement of wear resistance in epoxy composites through the incorporation of calcined and natural diatom frustules (CDFs and NDFs) as reinforcing fillers. The CDFs, pre-calcined at 1200 degrees C during manufacturing to improve structural integrity and eliminate organic matter, were supplied in processed form. Both CDFs and NDFs were subsequently wet-sieved (below 325 mesh) and dried at 120 degrees C for 2 h to ensure particle uniformity and moisture removal. Epoxy composites were prepared with 5-20 wt% frustule content. The fillers were ultrasonically dispersed in the epoxy matrix to improve uniformity and reduce agglomeration, followed by vacuum degassing and thermal curing. Wear performance was initially evaluated for all samples at a fixed 1000-cycle duration. Based on preliminary results, composites with 15 wt% and 20 wt% filler content which showed the highest wear resistance, were further tested under varying sliding distances corresponding to 300-1000 cycles to examine long-term behavior. Tests were conducted under dry sliding conditions using a block-on-ring tribometer at 50 N load. Using a systematic modeling-design-optimization framework, the study defines diatom weight fraction, sliding test duration, and frustule type as design variables. The experimental process was modeled through multiple nonlinear neuro-regression analyses, selecting the most realistic model based on Rtraining2\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$R_{{{\text{training}}}}<^>{2}$$\end{document}, Rtesting2\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$R_{{{\text{testing}}}}<^>{2}$$\end{document}, Radjusting2\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$R_{{{\text{adjusting}}}}<^>{2}$$\end{document}, and stability evaluations from 13 functional structures, with a second-order trigonometric nonlinear type model (SOTN) as the highest predictive performance. Stochastic optimization methods-including Modified Differential Evolution (MDE), Modified Nelder-Mead (MNM), Modified Simulated Annealing (MSA), and Modified Random Search (MRS)-were employed under three design scenarios to determine optimal wear parameters. The results revealed that epoxy composites containing 15 wt% NDFs exhibited the most substantial improvement, with a 95% reduction in specific wear rate (SWR) compared to neat epoxy and a 60% reduction relative to CDF-filled composites. The lowest optimized specific wear rate achieved was 1.086 x 10-5 mm3/N<middle dot>m. This work offers a comprehensive framework integrating material processing, statistical modeling, and stochastic optimization for the design of high-performance, wear-resistant epoxy composites.
  • Article
    Citation - WoS: 1
    Citation - Scopus: 1
    Abnormally Accumulated Gm2 Ganglioside Contributes To Skeletal Deformity in Tay-Sachs Mice
    (Springer Heidelberg, 2024) Demir, Secil Akyildiz; Seyrantepe, Volkan
    Tay-Sachs Disease is a rare lysosomal storage disorder caused by mutations in the HEXA gene, responsible for the degradation of ganglioside GM2. In addition to progressive neurodegeneration, Tay-Sachs patients display bone anomalies, including kyphosis. Tay-Sachs disease mouse model (Hexa-/-Neu3-/-) shows both neuropathological and clinical abnormalities of the infantile-onset disease phenotype. In this study, we investigated the effects of GM2 accumulation on bone remodeling activity. Here, we evaluated the bone phenotype of 5-month-old Hexa-/-Neu3-/- mice with age-matched control groups using gene expression analysis, bone plasma biomarker analysis, and micro-computed tomography. We demonstrated lower plasma alkaline phosphatase activity and calcium levels with increased tartrate-resistant acid phosphatase levels, indicating reduced bone remodeling activity in mice. Consistently, gene expression analysis confirmed osteoblast reduction and osteoclast induction in the femur of mice. Micro-computed tomography and analysis show reduced trabecular bone volume, mineral density, number, and thickness in Hexa-/-Neu3-/- mice. In conclusion, we demonstrated that abnormal GM2 ganglioside accumulation significantly triggers skeletal abnormality in Tay-Sachs mice. We suggest that further investigation of the molecular basis of bone structure anomalies is necessary to elucidate new therapeutic targets that prevent the progression of bone symptoms and improve the life standards of Tay-Sachs patients.