Seref Sagiroglu

• Ph.D.
• Head of Department at Gazi University

Intelligent transportation systems (ITS) involve collecting, storing, and delivering real-time traffic data to optimize efficiency, enhance transportation safety, and reduce energy consumption by integrating advanced electronics, information systems, and telecommunication technologies into roads, vehicles, and related infrastructure. These systems...

Contactless visualization of latent fingerprints has gained considerable attention for crime scene investigations as it can offer an option to collect traces using non-invasive and non-destructive treatment. Considering the complex structure of fingerprint development methods and the tedious process steps performed in these methods, new approaches...

Ensuring safety in smart buildings is crucial due to the increasing prevalence of smoke and fire hazards in modern environments. This paper introduces a novel privacy-preserving FL approach based on a CNN1D for smoke and fire detection in smart buildings. Our system integrates data from wearable environmental sensors to train a lightweight, edge-de...

Li-ion batteries are important in modern technology, especially for drones, due to their high energy density, long cycle life, and lightweight properties. Predicting their performance is crucial for enhancing drone flight safety, optimizing operations, and reducing costs. This involves using advanced techniques like machine learning (e.g., Convolut...

This study conducts a bibliometric analysis on 4,262 works published under the title “Generative Artificial Intelligence-GAI” between 2020 and 2024, sourced from Web of Science (WoS). The analysis covers keyword clouds, the most frequently used terms in article titles, types of publications, fields with the highest volume of publications. The resea...

Significant progress has been made recently with the contribution of technological advances in studies on brain cancer. Regarding this, identifying and correctly classifying tumors is a crucial task in the field of medical imaging. The disease-related tumor classification problem, on which deep learning technologies have also become a focus, is ver...

Management and information systems are considered two major disciplines that have to be combined to benefit from knowledge for rational decision-making which means strict procedures utilizing objective knowledge and logic for many years. Effective and efficient use of already invested organizational resources is a key subject to gain a competitive...

ChatGPT is a language model developed by OpenAI that uses generative artificial intelligence (GenAI) algorithms for natural language processing (NLP) tasks. It is a popular Chatbot due to its impressive ability to respond consistently to users' various prompts. In this study, the Public Personnel Selection Examination (KPSS) questions, organized by...

Introduction: Monitoring LDL-C levels is essential in clinical practice because there is a direct relation between low-density lipoprotein cholesterol (LDL-C) levels and atherosclerotic heart disease risk. Therefore, measurement or estimate of LDL-C is critical. The present study aims to evaluate Artificial Intelligence (AI) and Explainable AI (XAI...

Managing the capacity of lithium-ion batteries (LiBs) accurately, particularly in large-scale applications, enhances the cost-effectiveness of energy storage systems. Less frequent replacement or maintenance of LiBs results in cost savings in the long term. Therefore, in this study, AdaBoost, gradient boosting, XGBoost, LightGBM, CatBoost, and ense...

Smart grids are faced with a range of challenges, such as the development of communication infrastructure, cybersecurity threats, data privacy, and the protection of user information, due to their complex structure. Another key challenge faced by smart grids is the stability issues arising from variable energy sources and consumption patterns. In t...

The use of artificial intelligence (AI) approaches, one of the most significant technological advances of the 21st century, to determine the diode parameters that can be obtained from Schottky diode characterization allows data to be collected, processed, analyzed, and results obtained faster than ever before, with high accuracy. It also supports t...

Background: The aim of this paper is to report one of the significant applications of artificial intelligence (AI) and how it affects everyday clinical practice in neurosurgery. The authors present a case in which a patient was diagnosed via an AI algorithm during ongoing magnetic resonance imaging (MRI). According to this algorithm, the correspon...

This study provides a comparative analysis of the inferences that can be reached about preservice teachers' emotional awareness and personality traits when several alternative factor analytic models are tested simultaneously. An empirical illustration is provided using two datasets collected for a research study aiming to profile the social-emotion...

Privacy in magnetic resonance imaging (MRI) plays an important role due to violations occurring in scanning, storing, transferring, analyzing, and sharing. This paper reviews privacy concerns in MRI and especially Brain MRI in terms of datasets, models, platforms, violations, solutions used in privacy and security in the literature, discusses impor...

Artificial intelligence (AI) applications have become popular due to their advantages in solving health problems with high accuracy and confidence. One such application is the diagnosis of brain tumors or anomalies. This paper presents two new approaches for brain tumor grade classification and segmentation. Convolutional neural network (CNN) model...

In recent years, there has been a significant increase in the use of renewable energy (RE) resources in order to produce cleaner energy. The impact of decisions made by artificial intelligence models on energy efficiency is very important in the transition to these resources. With eXplainable Artificial Intelligence (XAI), various methods have been...

Lifestyles of individuals have changed drastically in the last two decades with the impact of social media platforms which transforms individuals from being users into an asset of social media. The assets now become very precious and seriously attract who can generate useful or harmful values. In this context, studies conducted in the last 5 years...

Yapay Zekâ ve Büyük Veri Kitap Serisi fikri Cumhurbaşkanlığı Dijital Dö- nüşüm Ofisi ile yaptığımız Türk Beyin Projesi kapsamında yürütülen işbirliği projesi kapsamında ortaya çıkmıştır. Gerek Gazi Üniversitesinde yaptığımız çalışmalar gerekse ülkemizde bu konuda yapılan çalışmalar incelendiğinde, dünyada büyük veri ve yapay zekâ konusunda çok fazl...

(Accepted Paper: https://bit.ly/ACCBARPaper) Although several binary classification performance metrics have been defined, a few of them are used for performance evaluation of classifiers and performance comparison/reporting in the literature. Specifically, F1 and Accuracy (ACC) are the most known and conventionally used metrics. Despite their popu...

Although few performance evaluation instruments have been used conventionally in different machine learning-based classification problem domains, there are numerous ones defined in the literature. This study reviews and describes performance instruments via formally defined novel concepts and clarifies the terminology. The study first highlights th...

The aim of the study is to review XAI studies in terms of their solutions, applications and challenges in renewable energy and resources. The results have shown that XAI really helps to explain how the decisions are made by AI models, to increase confidence and trust to the models, to make decision mode reliable, show the transparency of decision-m...

DDoS (Distributed Denial-of-Service) Dağıtık Hizmet Engelleme/Aksattırma Saldırılarının interneti tehdidi gün geçtikçe artmaktadır. Güncel veriler ve hazırlanan güvenlik raporları tehditlerin her geçen gün de artacağına yönelik veriler sunmaktadır. Tehditlerin artmasına paralel olarak alınan önlemlerde çeşitlenmektedir. Bu bölümünde; DDoS tanımı ve...

Data privacy is a challenging trade-off problem between privacy preserving and data utility. Anonymization is a fundamental approach for privacy preserving and also a hard trade-off problem. It enables to hide the identities of data subjects or record owners and requires to be developed near-optimal solutions. In this paper, a new multidimensional...

The number of users of social networking environments is increasing day by day. In parallel with the number of users, new social networking platforms are also taking place on the internet according to the wishes and needs of the users. Social networking environments, which are in an indispensable position with the instinct of socialization, also pr...

Bilişim teknolojilerindeki gelişmeler ile kullanıcı adı, şifre gibi doğrulama me- kanizmalarının yerini günümüzde daha güvenli olmaları sebebiyle biyometrik sistemler almıştır. Birçok alanda yaygın olarak kullanılan biyometrik sistemlerin beklenildiği şekilde güvenli sistemler olup olmadığını belirlemek üzere çalış- malar yürütülmüştür. Yapılan a...

Social media platforms have become popular news sources thanks to their immense popularity and high speed of information dissemination. Using these platforms is essential for news organizations and journalists to track and discover news in digital journalism age. However, the abundance of meaningless data and the lack of organization on these platf...

Büyük şehirlerin gelişimi ve buna bağlı olarak artan araç sayısı şehirler için şehir trafiğini arttırmakta, ulaşım sorununu ön plana çıkarmaktadır. Şehir trafiğini yönetmek için kamu ve özel kurumlar tarafından akıllı ulaşım ve yönetim sistemleri geliştirilmekte, bu sistemleri kullanarak trafik bileşenlerinden trafik akış, yoğunluk ve hız parametre...

Most of data in various forms contain sensitive information about individuals and so publishing such data might violate privacy. Privacy preserving data publishing (PPDP) is an essential for publishing useful data while preserving privacy. Anonymization, which is a utility based privacy preserving approach, helps hiding the identities of data subje...

Federated Learning (FL) is a suitable solution for making use of sensitive data belonging to patients, people, companies, or industries that are obligatory to work under rigid privacy constraints. FL mainly or partially supports data privacy and security issues and provides an alternative to model problems facilitating multiple edge devices or orga...

(Accepted Paper: https://bit.ly/TasKar2021, Online Material: https://github.com/gurol/TasKar) This study covers almost the ultimate set of binary-classification performance instruments derived from four dimensions of a confusion matrix, namely true positives/negatives and false positives/negatives and enhances their representation by establishing a...

This paper proposes a systematic benchmarking method called BenchMetrics to analyze and compare the robustness of binary-classification performance metrics based on the confusion matrix for a crisp classifier. BenchMetrics, introducing new concepts such as meta-metrics (metrics about metrics) and metric-space, has been tested on fifteen well-known...

Konum tabanlı servisler (KTS), sağladıkları bilgi ve yönlendirmeler ile gündelik hayatı kolaylaştırmaktadır. Kullanıcıların KTS’leri kullanarak gezinmesi sonucu elde edilen konum bilgileri zamana göre sıralandığında, yörünge verileri oluşmaktadır. Bu veriler, KTS sağlayıcıları tarafından toplanmakta, depolanmakta, işlenmekte ve çeşitli gerekçelerle...

BenchMetrics: inputs, stages, outputs, evaluation criteria/meta-metrics for metrics and metric-spaces. The method was tested for the benchmarking data for 13 metrics (Experiment-1) and 15 metrics with two recently proposed metrics (Experiment-2). The evaluated metrics are ranked according to overall robustness values. The experiments also provide s...

Fraud detection; Time series; Deep learning; Explainable artificial intelligence; Image conversion The increase in the volume and velocity of credit card transactions causes class imbalance and concept deviation problems in data sets where credit card fraud is detected. These problems make it very difficult for traditional approaches to produce rob...

Yazılım Tanımlı Ağlar (SDN) ve Ağ Fonksiyonlarını Sanallaştırma (NFV) tabanlı 5G ağlarında güvenlik; saldırı tespit sistemi ve güvenlik duvarı gibi güvenlik fonksiyonlarının NFV ile sanallaştırılması ve birer yazılım haline getirilerek SDN mimarisindeki genel amaçlı sunucular üzerinde çalıştırılması ile sağlanmaktadır. 5G ağlarında, sanal ağ güvenl...

Günümüzün en önemli teknolojilerinden olan büyük veri ve yapay zekâ, insanlara, kurumlara, işletmelere ve sistemlere pek çok alanda büyük fırsatlar sunmaktadır. Bu fırsatları doğru değerlendirebilmek adına, elde edilen verilerin doğru teknikler, teknolojiler, modeller ile analiz edilmesi, yorumlanması ve anlamlandırılması gerekir. Kişisel verileri...

In Network Functions Virtualization (NFV) environments, network security is provided with the deployment of virtual security functions (VSF) on general-purpose servers to filter and monitor the incoming traffic. However, the traffic handled by VSFs may have different security requirements in a network. On the other hand, there are some operational...

Bu çalışmada, filo yönetim sistemlerinin eksikleri hem büyük veri hem de sürücü davranışı bakış açılarıyla incelenmiş, gerçek veriler üzerinde sürücü/sürüş davranışları analiz edilmiş bunun sonucunda veri analizlerini gerçekleştirmek için büyük veri tabanlı yeni modeller önerilmiştir. Büyük veri üzerinde 6 farklı senaryo ile filodaki sürücülerin da...

Aim: During daily practice of neurosurgery, especially in sub-specializations such as radiosurgery, tumor segmentation is essential and time consuming. Artificial intelligence methods are getting widely used for such purposes. In this study we propose a deep convolutional generative adversarial networks (DCGAN) model which learns normal brain MRI...

Verinin boyut ve çeşitlilik olarak arttığı, kişisel verilerin kolaylıkla paylaşıldığı ve ihlallerinin sayısının hızla yükseldiği günümüzde veri mahremiyeti, üzerinde çokça çalışılan ve önlemler geliştirilen konuların başında gelmektedir. Kişisel verileri kullanan, depolayan veya işleyen her türlü uygulama, ürün veya sistem, veri mahremiyetini sağla...

Biometry is essential when it comes to personal identification and verification in forensic applications, and the fingerprint is one of the most commonly used biometric features in the field of biometric identification. To detect fingerprints at the crime scene, to collect and transfer fingerprints in a way not to modify its nature, to make appropr...

Software Defined Networking (SDN) and Network Function Virtualization (NFV) are the latest promising technologies introduced with the goal of making networks more flexible, controllable, cost-efficient and innovative. These technologies are recognized as building blocks for the future Internet. Through the use of NFV, network functions are virtuali...

The class imbalance problem, one of the common data irregularities, causes the development of under-represented models. To resolve this issue, the present study proposes a new cluster-based MapReduce design, entitled Distributed Cluster-based Resampling for Imbalanced Big Data (DIBID). The design aims at modifying the existing dataset to increase t...

Smart grid systems are complex and huge power networks including many digital components and assets. These systems provide opportunities to operators to collect data remotely from customers and manage their network reliably and effectively. Therefore, the operators can track and analyze historical and immediate power consumption data, and take nece...

Veri mahremiyeti, mahremiyet riskleri ile veriden sağlanan fayda arasındaki en iyi dengeyi bulmaya çalışan zor bir problemdir. Anonimleştirme, veri mahremiyetinin sağlanmasında yaygın olarak kullanılan fayda temelli çözümlerin başında gelir. Mahremiyet risklerini arttıran ve veri faydasını olumsuz etkileyen aykırı kayıtların anonimleştirme sürecind...

Teknolojinin gelişmesi ile beraber veri üretim ve işleme hızı artmış, bunun sonucu olarak hacim, hız, çeşitlilik ve değer gibi bileşenlere sahip büyük veri kavramı ortaya çıkmıştır. Büyük verilerden elde edilecek faydayı arttırmak için bu verilerin mahremiyetini koruyarak paylaşmak veya yayınlamak gerekir. Literatür incelendiğinde, büyük verinin ma...

Software Defined Networking (SDN) and Network Functions Virtualization (NFV) are two important technologies gaining prominence thanks to their benefits for improving the flexibility and cost efficiency in networks. These technologies have been utilized extensively for providing new age security solutions in recent years. Through the use of SDN and...

İnternet kullanımının yaygınlaşması ile birlikte son kullanıcılar, yaşamlarının büyük bir kısmını sanal ortamlarla etkileşim içerisinde geçirmektedir. Kötü niyetli saldırganlar bireysel/siyasal/ekonomik fikirleri, inançları, hırsları, hedefleri, çıkarları, beklentileri veya misyonları doğrultusunda sanal ortamları kendi gruplarının, toplumlarının v...

Anonymization is a privacy-preserving approach facilitating to protect the identities of data subjects. Besides privacy, anonymization presents a data utility that is very important for data analytics. The accuracy of a data analytics model, which is created on anonymous data, depends on the utility provided by anonymization. While there exist some...

Aim: The increasing number of magnetic resonance imaging (MRI) studies could lead to delayed or missed diagnosis of significant brain pathologies like high-grade gliomas (HGG). Artificial intelligence methods could be applied in analyzing large amounts of data such as; brain MRI studies. In this study we aimed to propose a convolutional neural net...

Bilgi Güvenliği Derneği (BGD), kuruluşundan bugüne kadar ülkemizin bilgi ve siber güvenliği ile savunmasının gelişimine katkı sağlamakta, birikimini çevreye aktarmakta, bilgi güvenliği alanında açık kaynak yaklaşımını benimseyen ve bu kapsamda içerik üretilmesine ve geliştirilmesine destek vermekte, bunları yaymakta, paylaşmakta ve kamuoyunun kulla...

Siber terörizm eylemlerinde etkili bir araç olarak kullanılan DDoS saldırıları 1980’li yıllarda amatör bilgisayar korsanları (script kiddies) tarafından oyun/gösteriş amaçlı gerçekleştirilmeye başlamıştır. Bu saldırılar ile ciddi ekonomik zararlar verebileceğini fark eden siber suçlular, 90’lı yıllarda DDoS saldırılarını elektronik ticaret şirketle...

Bu makale, sadece parmak izlerinden cinsiyetlerin tahmin edilmesi için Yapay Sinir Ağları (YSA) modeli tabanlı yeni bir metod önermektedir. Modelleme işlemleri parmak izlerinin alınması, elde edilen bir parmak izi bölümünün (örneğin 5x5mm) farklı boyutlarının analiz edimesi, köşegen çizgisinin çizilmesi, köşegen çizgisi üzerindeki tepe çizgilerinin...

This paper presents a review on how to benefit from software-defined networking (SDN) to enhance smart grid security. For this purpose, the attacks threatening traditional smart grid systems are classified according to availability, integrity, and confidentiality, which are the main cyber-security objectives. The traditional smart grid architecture...

This paper presents a review on how to benefit from software-defined networking (SDN) to enhance smart grid security. For this purpose, the attacks threatening traditional smart grid systems are classified according to availability, integrity, and confidentiality, which are the main cyber-security objectives. The traditional smart grid architecture...

As the volume, variety, velocity aspects of big data are increasing, the other aspects such as veracity, value, variability, and venue could not be interpreted easily by data owners or researchers. The aspects are also unclear if the data is to be used in machine learning studies such as classification or clustering. This study proposes four techni...

In order to gain more benefits from big data, they must be shared, published, analyzed and processed without having any harm or facing any violation and finally get better values from these analytics. The literature reports that this analytics brings an issue of privacy violations. This issue is also protected by law and bring fines to the companie...

There are many articles published in driving/driver behavior (DDB) but few of them have focused on DDB with big data in the literature. The reasons for this might be the lack of media coverage, data, expertise or big data perspectives. This paper presents a big data perspective for investigating the DDB based on models, data features, and experienc...

NFV (Network Functions Virtualization) is one of the latest promising technologies making networks more flexible, controllable, cost-efficient and innovative. NFV is being utilized extensively for providing cutting edge networking solutions, including virtual cyber security functions. Functions virtualized with NFV such as firewall, deep packet ins...

In today's, the golden age of digitalization, it is experienced change and development in the field of auditing as it is in almost every area. Big Datas that, occurs to define the exponential growth and usability of data generated by humans, applications and intelligent machines, affects the audit process. The audit of the future will be quite diff...

ENGLISH: Conventional energy grids growing in time have become complex, inefficient and expensive to operate and use. They are critical because of providing the whole energy needs of the technologies required for our modern life but also cumbersome entities. “Smarting” the grids by automating, facilitating the troubleshooting and productivity analy...