Vaggelis Kapoulas

Dr. Vaggelis Kapoulas


Research Focus & Metrics

Academic Career Length

31Years (1996-Present)

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

Representative Publications

View All Publications
20 February 2023 in Machines
Verified
Journal Article
Open access
PDF file
IDIoannis Daramouskas
Ioannis Daramouskas
DMDimitrios Meimetis
Dimitrios Meimetis
NPNiki Patrinopoulou
Niki Patrinopoulou
Vaios LappasVaios Lappas
Vaios Lappas
Vassilis KostopoulosVassilis Kostopoulos
Vassilis Kostopoulos
VKVaggelis Kapoulas
Vaggelis Kapoulas
Multiple-object detection, localization, and tracking are desirable in many areas and applications, as the field of deep learning has developed and has drawn the attention of academics in computer vision, having a plethora of networks now achieving excellent accuracy in detecting multiple objects in an image. Tracking and localizing objects still remain difficult processes which require significant effort. This work describes an optical camera-based target detection, tracking, and localization solution for Unmanned Aerial Vehicles (UAVs). Based on the well-known network YOLOv4, a custom object detection model was developed and its performance was compared to YOLOv4-Tiny, YOLOv4-608, and YOLOv7-Tiny. The target tracking algorithm we use is based on Deep SORT, providing cutting-edge tracking. The proposed localization approach can accurately determine the position of ground targets identified by the custom object detection model. Moreover, an implementation of a global tracker using localization information from up to four UAV cameras at a time. Finally, a guiding approach is described, which is responsible for providing real-time movement commands for the UAV to follow and cover a designated target. The complete system was evaluated in Gazebo with up to four UAVs utilizing Software-In-The-Loop (SITL) simulation.

19 August 2016 in Peer-to-Peer Networking and Applications
Verified
Journal Article
Closed access
PDF file
SAShakeel Ahmad
Shakeel Ahmad
Christos BourasChristos Bouras
Christos Bouras
EBEliya Buyukkaya
Eliya Buyukkaya
MDMuneeb Dawood
Muneeb Dawood
RHRaouf Hamzaoui
Raouf Hamzaoui
GSGwendal Simon
Gwendal Simon

29 April 2025 in Computers
Verified
Journal Article
Open access
PDF file
KKKonstantinos Kyritsis
Konstantinos Kyritsis
CLCharalampos M Liapis
Charalampos M Liapis
Isidoros PerikosIsidoros Perikos
Isidoros Perikos
Michael ParaskevasMichael Paraskevas
Michael Paraskevas
VKVaggelis Kapoulas
Vaggelis Kapoulas
This study conducts an in-depth investigation of the performance of six transformer models using 12 different datasets—10 with three classes and two with two classes—on sentiment classification. We use these six models and generate all combinations of triple schema ensembles, Majority and Soft vote. In total, we compare 46 classifiers on each dataset and see in one case up to a 7.6% increase in accuracy on a dataset with three classes from an ensemble scheme and, in a second case, up to 8.5% increase in accuracy on a dataset with two classes. Our study contributes to the field of natural language processing by exploring the reasons for the predominance, in this particular task, of Majority vote over Soft vote. The conclusions are drawn after a thorough investigation of the classifiers that are co-compared with each other through reliability charts, analyses of the confidence the models have in their predictions and their metrics, concluding with statistical analyses using the Friedman test and the Nemenyi post-hoc test with useful conclusions.

6 September 2024 in Smart Cities
Verified
Journal Article
Open access
PDF file
IDIoannis Daramouskas
Ioannis Daramouskas
Isidoros PerikosIsidoros Perikos
Isidoros Perikos
Michael ParaskevasMichael Paraskevas
Michael Paraskevas
Vaios LappasVaios Lappas
Vaios Lappas
VKVaggelis Kapoulas
Vaggelis Kapoulas
LoRa technology is a recent technology belonging to the Low Power and Wide Area Networks (LPWANs), which offers distinct advantages for wireless communications and possesses unique features. Among others, it can be used for localization procedures offering minimal energy consumption and quite long-range transmissions. However, the exact capabilities of LoRa localization performance are yet to be employed thoroughly. This article examines the efficiency of the LoRa technology in localization tasks using Time Difference of Arrival (TDoA) measurements. An extensive and concrete experimental study was conducted in a real-world setup on the University of Patras campus, employing both real-world data and simulations to assess the precision of geodetic coordinate determination. Through our experiments, we implemented advanced localization algorithms, including Social Learning Particle Swarm Optimization (PSO), Least Squares, and Chan techniques. The results are quite interesting and highlight the conditions and parameters that result in accurate LoRa-based localization in real-world scenarios in smart cities. In our context, we were able to achieve state-of-the-art localization results reporting localization errors as low as 300 m in a quite complex 8 km × 6 km real-world environment.

2 June 2026 in AI in Education
Verified
Journal Article
Open access
PDF file
Panagiota MantaliaPanagiota Mantalia
Panagiota Mantalia
CLCharalampos M Liapis
Charalampos M Liapis
EPEpameinondas Panagopoulos
Epameinondas Panagopoulos
VKVaggelis Kapoulas
Vaggelis Kapoulas
Michael ParaskevasMichael Paraskevas
Michael Paraskevas
This systematic review examines research published between 2021 and 2025 on generative AI and chatbot use in secondary education across nine countries in Southern Europe and the Balkans: Greece, Italy, Spain, Portugal, Malta, Serbia, Croatia, Bulgaria, and Romania. Drawing on studies from IEEE Xplore, the ACM Digital Library, Google Scholar, and arXiv, this review synthesizes evidence on instructional uses, reported learning outcomes, teacher readiness, governance, and language-localization constraints. Across the region, the literature shows rapid experimentation in writing, language learning, programming, and project-based learning but limited long-term evaluation and weak cross-country comparability. Teacher interest is high, yet institutional guidance, assessment frameworks, and local-language resources remain uneven. This review argues that the next phase of adoption should move from isolated classroom experimentation to system-level implementation built around teacher AI literacy, transparent assessment, and context-sensitive design for smaller linguistic ecosystems.

6 March 2026 in Administrative Sciences
Verified
Journal Article
Open access
PDF file
OBOurania Bousiou
Ourania Bousiou
Michael ParaskevasMichael Paraskevas
Michael Paraskevas
VKVaggelis Kapoulas
Vaggelis Kapoulas
Panagiotis G LiargovasPanagiotis G Liargovas
Panagiotis G Liargovas
This study examines administrative employees’ perceptions of integrating Artificial Intelligence (AI) into the administration of Greek public universities. Using a cross-sectional online questionnaire administered across three universities (N = 127), we map perceptions across five domains: (i) perceived efficiency/effectiveness contributions, (ii) perceived automation benefits, (iii) perceived adoption challenges, (iv) perceived ethics and data protection requirements, and (v) perceived skills development needs. Results indicate a generally supportive climate for AI use in university administration, but support is conditional: ethics and data protection are prioritized most strongly, whereas perceived efficiency/effectiveness gains are closer to neutral-to-slightly positive. Respondents endorse task-level automation more than broad organizational performance claims and emphasize training and human oversight as enabling conditions for responsible deployment. These findings suggest that a governance-first and capacity-first implementation pathway may be more aligned with staff priorities in the Greek public university context. The study provides an exploratory baseline for future evaluative research on AI-enabled administrative modernization.