Metin Zontul

Prof. Dr. Metin Zontul

orcid

Research Focus & Metrics

Academic Career Length

7Years (2020-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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5 February 2024 in Tomography
Verified
Journal Article
Open access
PDF file
ŞAŞükran YAMAN ATCI
Şükran YAMAN ATCI
ALİ GÜNEŞALİ GÜNEŞ
ALİ GÜNEŞ
MZMetin Zontul
Metin Zontul
ZDZafer ASLAN (Prof. Dr.)
Zafer ASLAN (Prof. Dr.)
Diagnosing and screening for diabetic retinopathy is a well-known issue in the biomedical field. A component of computer-aided diagnosis that has advanced significantly over the past few years as a result of the development and effectiveness of deep learning is the use of medical imagery from a patient’s eye to identify the damage caused to blood vessels. Issues with unbalanced datasets, incorrect annotations, a lack of sample images, and improper performance evaluation measures have negatively impacted the performance of deep learning models. Using three benchmark datasets of diabetic retinopathy, we conducted a detailed comparison study comparing various state-of-the-art approaches to address the effect caused by class imbalance, with precision scores of 93%, 89%, 81%, 76%, and 96%, respectively, for normal, mild, moderate, severe, and DR phases. The analyses of the hybrid modeling, including CNN analysis and SHAP model derivation results, are compared at the end of the paper, and ideal hybrid modeling strategies for deep learning classification models for automated DR detection are identified.
1

17 May 2023 in Applied Sciences
Verified
Journal Article
Open access
PDF file
IYIlkay Yelmen
Ilkay Yelmen
ALİ GÜNEŞALİ GÜNEŞ
ALİ GÜNEŞ
MZMetin Zontul
Metin Zontul
With the recent growth of the Internet, the volume of data has also increased. In particular, the increase in the amount of unstructured data makes it difficult to manage data. Classification is also needed in order to be able to use the data for various purposes. Since it is difficult to manually classify the ever-increasing volume data for the purpose of various types of analysis and evaluation, automatic classification methods are needed. In addition, the performance of imbalanced and multi-class classification is a challenging task. As the number of classes increases, so does the number of decision boundaries a learning algorithm has to solve. Therefore, in this paper, an improvement model is proposed using WordNet lexical ontology and BERT to perform deeper learning on the features of text, thereby improving the classification effect of the model. It was observed that classification success increased when using WordNet 11 general lexicographer files based on synthesis sets, syntactic categories, and logical groupings. WordNet was used for feature dimension reduction. In experimental studies, word embedding methods were used without dimension reduction. Afterwards, Random Forest (RF), Support Vector Machine (SVM) and Multi-Layer Perceptron (MLP) algorithms were employed to perform classification. These studies were then repeated with dimension reduction performed by WordNet. In addition to the machine learning model, experiments were also conducted with the pretrained BERT model with and without WordNet. The experimental results showed that, on an unstructured, seven-class, imbalanced dataset, the highest accuracy value of 93.77% was obtained when using our proposed model.
1

24 January 2024 in Computation
Verified
Journal Article
Open access
PDF file
HTHayati TUTAR
Hayati TUTAR
ALİ GÜNEŞALİ GÜNEŞ
ALİ GÜNEŞ
MZMetin Zontul
Metin Zontul
ZDZafer ASLAN (Prof. Dr.)
Zafer ASLAN (Prof. Dr.)
With the rapid development in technology in recent years, the use of cameras and the production of video and image data have similarly increased. Therefore, there is a great need to develop and improve video surveillance techniques to their maximum extent, particularly in terms of their speed, performance, and resource utilization. It is challenging to accurately detect anomalies and increase the performance by minimizing false positives, especially in crowded and dynamic areas. Therefore, this study proposes a hybrid video anomaly detection model combining multiple machine learning algorithms with pixel-based video anomaly detection (PBVAD) and frame-based video anomaly detection (FBVAD) models. In the PBVAD model, the motion influence map (MIM) algorithm based on spatio–temporal (ST) factors is used, while in the FBVAD model, the k-nearest neighbors (kNN) and support vector machine (SVM) machine learning algorithms are used in a hybrid manner. An important result of our study is the high-performance anomaly detection achieved using the proposed hybrid algorithms on the UCF-Crime data set, which contains 128 h of original real-world video data and has not been extensively studied before. The AUC performance metrics obtained using our FBVAD-kNN algorithm in experiments were averaged to 98.0%. Meanwhile, the success rates obtained using our PBVAD-MIM algorithm in the experiments were averaged to 80.7%. Our study contributes significantly to the prevention of possible harm by detecting anomalies in video data in a near real-time manner.
1

6 February 2026 in Applied Fruit Science
Verified
Journal Article
Closed access
PDF file
EYEsra Kavalcı Yılmaz
Esra Kavalcı Yılmaz
KAKemal Adem
Kemal Adem
MZMetin Zontul
Metin Zontul

16 January 2024 in La Matematica
Verified
Journal Article
Closed access
PDF file
SKSeda Karateke
Seda Karateke
MZMetin Zontul
Metin Zontul
Lakshmi Narayan MishraLakshmi Narayan Mishra
Lakshmi Narayan Mishra
AGAsha Ram Gairola
Asha Ram Gairola

7 November 2025 in Diagnostics
Verified
Journal Article
Open access
PDF file
MCMehmet akif Cifci
Mehmet akif Cifci
Batuhan ÖNEYBatuhan ÖNEY
Batuhan ÖNEY
FYFazli Yildirim
Fazli Yildirim
HBHülya YILMAZ BAŞER
Hülya YILMAZ BAŞER
MZMetin Zontul
Metin Zontul
Background: This study introduces the Adaptive Graph Fusion Network, an interpretable graph-based learning framework developed for large-scale prediction of intensive care outcomes. The proposed model dynamically constructs patient similarity networks through a density-aware kernel that adjusts neighborhood size based on local data distribution, thereby representing both frequent and rare clinical patterns. Methods: To characterize physiological evolution over time, the framework integrates a short-horizon convolutional encoder that captures acute variations in vital signs and laboratory results with a long-horizon recurrent memory unit that models gradual temporal trends. The approach was trained and internally validated on the publicly available eICU Collaborative Research Database, which includes more than 200,000 admissions from 208 hospitals across the United States. Results: The model achieved a mean area under the receiver operating characteristic curve of 0.91 across six critical outcomes, with in-hospital mortality reaching 0.96, outperforming logistic regression, temporal long short-term memory networks, and calibrated Transformer-based architectures. Feature attribution analysis using SHAP and temporal contribution mapping identified lactate trajectories, creatinine fluctuations, and vasopressor administration as dominant determinants of risk, consistent with established clinical understanding while revealing additional temporal dependencies overlooked by existing scoring systems. Conclusions: These findings demonstrate that adaptive graph construction combined with multi-horizon temporal reasoning improves predictive reliability and interpretability in heterogeneous intensive care populations, offering a transparent and reproducible foundation for future research in clinical machine learning.