Metehan Unal

Mr. Metehan Unal

Department of Computer Engineering, Ankara University, Ankara, Turkey (Türkiye)
orcid

Research Focus & Metrics

Academic Career Length

9Years (2018-Present)

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

Representative Publications

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13 March 2023 in Sensors
Verified
Journal Article
Open access
PDF file
Erkan BostanciErkan Bostanci
Erkan Bostanci
EKEngin Kocak
Engin Kocak
Metehan UnalMetehan Unal
Metehan Unal
MGMehmet Serdar Güzel
Mehmet Serdar Güzel
KAKoray Açıcı
Koray Açıcı
TATunc Asuroglu
Tunc Asuroglu
Data from omics studies have been used for prediction and classification of various diseases in biomedical and bioinformatics research. In recent years, Machine Learning (ML) algorithms have been used in many different fields related to healthcare systems, especially for disease prediction and classification tasks. Integration of molecular omics data with ML algorithms has offered a great opportunity to evaluate clinical data. RNA sequence (RNA-seq) analysis has been emerged as the gold standard for transcriptomics analysis. Currently, it is being used widely in clinical research. In our present work, RNA-seq data of extracellular vesicles (EV) from healthy and colon cancer patients are analyzed. Our aim is to develop models for prediction and classification of colon cancer stages. Five different canonical ML and Deep Learning (DL) classifiers are used to predict colon cancer of an individual with processed RNA-seq data. The classes of data are formed on the basis of both colon cancer stages and cancer presence (healthy or cancer). The canonical ML classifiers, which are k-Nearest Neighbor (kNN), Logistic Model Tree (LMT), Random Tree (RT), Random Committee (RC), and Random Forest (RF), are tested with both forms of the data. In addition, to compare the performance with canonical ML models, One-Dimensional Convolutional Neural Network (1-D CNN), Long Short-Term Memory (LSTM), and Bidirectional LSTM (BiLSTM) DL models are utilized. Hyper-parameter optimizations of DL models are constructed by using genetic meta-heuristic optimization algorithm (GA). The best accuracy in cancer prediction is obtained with RC, LMT, and RF canonical ML algorithms as 97.33%. However, RT and kNN show 95.33% performance. The best accuracy in cancer stage classification is achieved with RF as 97.33%. This result is followed by LMT, RC, kNN, and RT with 96.33%, 96%, 94.66%, and 94%, respectively. According to the results of the experiments with DL algorithms, the best accuracy in cancer prediction is obtained with 1-D CNN as 97.67%. BiLSTM and LSTM show 94.33% and 93.67% performance, respectively. In classification of the cancer stages, the best accuracy is achieved with BiLSTM as 98%. 1-D CNN and LSTM show 97% and 94.33% performance, respectively. The results reveal that both canonical ML and DL models may outperform each other for different numbers of features.

1 September 2023 in Diagnostics
Verified
Journal Article
Open access
PDF file
Metehan UnalMetehan Unal
Metehan Unal
Erkan BostanciErkan Bostanci
Erkan Bostanci
COCeren Ozkul
Ceren Ozkul
KAKoray Açıcı
Koray Açıcı
TATunc Asuroglu
Tunc Asuroglu
MGMehmet Serdar Güzel
Mehmet Serdar Güzel
Human microbiota refers to the trillions of microorganisms that inhabit our bodies and have been discovered to have a substantial impact on human health and disease. By sampling the microbiota, it is possible to generate massive quantities of data for analysis using Machine Learning algorithms. In this study, we employed several modern Machine Learning techniques to predict Inflammatory Bowel Disease using raw sequence data. The dataset was obtained from NCBI preprocessed graph representations and converted into a structured form. Seven well-known Machine Learning frameworks, including Random Forest, Support Vector Machines, Extreme Gradient Boosting, Light Gradient Boosting Machine, Gaussian Naïve Bayes, Logistic Regression, and k-Nearest Neighbor, were used. Grid Search was employed for hyperparameter optimization. The performance of the Machine Learning models was evaluated using various metrics such as accuracy, precision, fscore, kappa, and area under the receiver operating characteristic curve. Additionally, Mc Nemar’s test was conducted to assess the statistical significance of the experiment. The data was constructed using k-mer lengths of 3, 4 and 5. The Light Gradient Boosting Machine model overperformed over other models with 67.24%, 74.63% and 76.47% accuracy for k-mer lengths of 3, 4 and 5, respectively. The LightGBM model also demonstrated the best performance in each metric. The study showed promising results predicting disease from raw sequence data. Finally, Mc Nemar’s test results found statistically significant differences between different Machine Learning approaches.

1 June 2020 in Digital Applications in Archaeology and Cultural Heritage
Verified
Journal Article
Closed access
Metehan UnalMetehan Unal
Metehan Unal
EBErkan Bostanci
Erkan Bostanci
ESEvren Sertalp
Evren Sertalp

1 October 2018
Verified
Conference Paper
Closed access
Metehan UnalMetehan Unal
Metehan Unal
Erkan BostanciErkan Bostanci
Erkan Bostanci
ESEvren Sertalp
Evren Sertalp
MGMehmet Serdar Guzel
Mehmet Serdar Guzel
NKNadia Kanwal
Nadia Kanwal
Augmented Reality (AR) already is very interesting topic for cultural heritage since it can be very easy to reconstruct the ancient building on the site without any physical intervention. With the AR technology, 3D models of ancient buildings can be overimposed to remains of the site. In this way historical sites become more interesting and appealing places. In this study, we developed a geo-location based AR application for Roman Baths of Ankara which is placed in Turkey. Novel part of this study is using drones for video source which model of the bath will be overlaid to it.

1 October 2018
Verified
Conference Paper
Closed access
YAYilmaz Ar
Yilmaz Ar
Metehan UnalMetehan Unal
Metehan Unal
SSSevgi Yigit Sert
Sevgi Yigit Sert
Erkan BostanciErkan Bostanci
Erkan Bostanci
NKNadia Kanwal
Nadia Kanwal
MGMehmet Serdar Guzel
Mehmet Serdar Guzel
In Augmented Reality (AR) applications, tracking the movements of user is the one of the most crucial issues. Because of the unpredictable structure of human movement, tracking the user with classical robot tracking methods can cause inaccurate result. In this study, motion different models for increasing the precision of human tracking using GPS-INS receiver was developed. First, a fuzzy motion model was developed and this model was improved using an evolutionary algorithm. With these algorithms allowing to choose between different motion models, transition among the motion models was achieved in real time and precision was increased for human tracking.

31 December 2020 in Communications Faculty of Sciences University of Ankara Series A2-A3 Physical Sciences and Engineering
Verified
Journal Article
Open access
PDF file
Metehan UnalMetehan Unal
Metehan Unal
Erkan BostanciErkan Bostanci
Erkan Bostanci
MGMehmet Serdar Güzel
Mehmet Serdar Güzel
AAAyhan AYDIN
Ayhan AYDIN
The intelligent machines concept is born in sci-fi scenarios. Today it seems to be we are much closer to realizing this idea than ever before. By imitating the human nervous system, machines can learn many things. This paper explains modern learning techniques like artificial neural networks, transfer learning. Later purposes an experiment to classify plant seedling images to test the transfer learning with two different CNN architectures. Although the architects were not actually created for this task, result were quite accurate for a different classification task.