Aris Leivadeas

109 papers A 2B 19C 4Misc 1Journal 43Unranked 39

Year	Rank	Type	Title / Venue / Authors
2026	A	`conf`	A Comprehensive Long-duration 8K Dataset to Benchmark Hardware Encoding for Live 360° Video Tiled Streaming. MMSys Olivier Brochu, Aris Leivadeas, Stéphane Coulombe
2026	J	`jnl`	An End-to-End Smart Radio Log Anomaly Detection Architecture for 5G/6G Networks. IEEE Commun. Mag. Marios Avgeris, Aroosa Hameed, Brian Le, Aris Leivadeas, Ioannis Lambadaris
2026	J	`jnl`	Detecting application transitions and identifying application types for intent-based network assurance: A machine learning perspective. Comput. Networks John Violos, Fotios Voutsas, Christos Diou, Aris Leivadeas
2026	J	`jnl`	Intent-Driven Smart Manufacturing Integrating Knowledge Graphs and Large Language Models. CoRR Takoua Jradi, John Violos, Dimitrios Spatharakis, Lydia Mavraidi, Ioannis Dimolitsas, Aris Leivadeas, Symeon Papavassiliou
2025	—	`conf`	A Comparative Study Between Containers and VMs with CPU Pinning, HugePages and NUMA Optimization. NFV-SDN Said Zidelmal, Aris Leivadeas
2025	J	`jnl`	A Smart City Assisted Internet of Military Defense Things Architecture. IEEE Internet Things Mag. Dimitra Tsiolis, Aris Leivadeas
2025	B	`conf`	Adaptive Federated Learning with Lyapunov Optimization for Robust Radio Link Failure Detection in 5G Networks. GLOBECOM Umar Farooq, Aroosa Hameed, Aris Leivadeas, Ioannis Lambadaris
2025	B	`conf`	Aligning Pre-Trained LLMs for Enhanced UAV Power Consumption Forecasting. GLOBECOM Aroosa Hameed, Syed Muhammad Danish, Aris Leivadeas
2025	J	`jnl`	An AI-Driven Intent-Based Network Architecture. IEEE Commun. Mag. Yosra Njah, Aris Leivadeas, Matthias Falkner
2025	B	`conf`	Compressing Data and Deep Learning Models for Green Edge Computing. GLOBECOM John Violos, Ioannis Fovakis, Aris Leivadeas
2025	J	`jnl`	Cooperative Learning-Based Framework for VNF Caching and Placement Optimization Over Low Earth Orbit Satellite Networks. IEEE Trans. Veh. Technol. Khai Doan, Marios Avgeris, Aris Leivadeas, Ioannis Lambadaris, Wonjae Shin
2025	J	`jnl`	EMDTORA: Energy-Aware Multi-User Dependent Task Offloading and Resource Allocation in MEC Using Graph-Enabled DRL. IEEE Trans. Green Commun. Netw. Sangrez Khan, Marios Avgeris, Julien Gascon-Samson, Aris Leivadeas
2025	J	`jnl`	Enabling semi-supervised learning in intrusion detection systems. J. Parallel Distributed Comput. Panagis Sarantos, John Violos, Aris Leivadeas
2025	—	`conf`	Energy-Aware Code Generation with LLMs: Benchmarking Small vs. Large Language Models for Sustainable AI Programming. FLLM Humza Ashraf, Syed Muhammad Danish, Aris Leivadeas, Yazan Otoum, Zeeshan Sattar
2025	J	`jnl`	Energy-Aware Code Generation with LLMs: Benchmarking Small vs. Large Language Models for Sustainable AI Programming. CoRR Humza Ashraf, Syed Muhammad Danish, Aris Leivadeas, Yazan Otoum, Zeeshan Sattar
2025	—	`conf`	Evaluating the performance of 5G Core NFV-based Deployments in AWS. NoF Nicolas Gagnon, Aris Leivadeas
2025	J	`jnl`	FEDORA: Federated Ensemble Reinforcement Learning for DAG-Based Task Offloading and Resource Allocation in MEC. IEEE Internet Things J. Sangrez Khan, Amir Ali Pour, Marios Avgeris, Julien Gascon-Samson, Aris Leivadeas
2025	J	`jnl`	FeD-TST: Federated Temporal Sparse Transformers for QoS Prediction in Dynamic IoT Networks. IEEE Trans. Netw. Serv. Manag. Aroosa Hameed, John Violos, Nina Santi, Aris Leivadeas, Nathalie Mitton
2025	B	`conf`	Inception-LSTM: A Two Stage Approach for Indoor Position Estimation Using Channel Impulse Response Measurements. GLOBECOM Aroosa Hameed, Ioannis Lambadaris, Ian D. Marsland, Roland Smith, Hazem Ibrahim, Syed Hassan Raza Naqvi, Aris Leivadeas
2025	—	`conf`	Intent-Driven Smart Manufacturing Integrating Knowledge Graphs and Large Language Models. ICKG Takoua Jradi, John Violos, Dimitrios Spatharakis, Lydia Mavraidi, Ioannis Dimolitsas, Aris Leivadeas, Symeon Papavassiliou
2025	—	`conf`	Network Assurance in Intent Based Data Center Networking: A Domain Shift Approach. NoF Steve Lévesque, Xiaoang Zheng, John Violos, Aris Leivadeas
2025	B	`conf`	OLIDA-IDS: Online Learning with Integrated Domain Adaptation for Intrusion Detection Systems. GLOBECOM John Violos, Christos Krikas, Panagis Sarantos, Aris Leivadeas
2025	—	`conf`	Transformer-Based Link Failure Detection in 5G Cellular Networks. ICC Umar Farooq, Aroosa Hameed, Aris Leivadeas, Ioannis Lambadaris
2025	J	`jnl`	Virtual sensors for smart farming: An IoT- and AI-enabled approach. Internet Things Athanasios Chourlias, John Violos, Aris Leivadeas
2024	J	`jnl`	A light-weight edge-enabled knowledge distillation technique for next location prediction of multitude transportation means. Future Gener. Comput. Syst. Stylianos Tsanakas, Aroosa Hameed, John Violos, Aris Leivadeas
2024	—	`conf`	An Incremental Learning Assurance Approach for Intent Based Networking Enabled Data Centers. IISA Steve Lévesque, Xiaoang Zheng, John Violos, Aris Leivadeas, Matthias Falkner
2024	J	`jnl`	Cooperative Learning-Based Framework for VNF Caching and Placement Optimization over Low Earth Orbit Satellite Networks. CoRR Khai Doan, Marios Avgeris, Aris Leivadeas, Ioannis Lambadaris, Wonjae Shin
2024	—	`conf`	DRL-based Trajectory Planning and Sensor Task Scheduling for Edge Robotics. WF-IoT Sirine Bouhoula, Marios Avgeris, Aris Leivadeas, Ioannis Lambadaris
2024	—	`conf`	Deep Learning-Based Anomaly Detection in 5G Cellular Networks. IISA Umar Farooq, Aroosa Hameed, Aris Leivadeas, Ioannis Lambadaris
2024	—	`conf`	Fragmentation-Aware VNF Placement: A Deep Reinforcement Learning Approach. ICC Ramy Mohamed, Marios Avgeris, Aris Leivadeas, Ioannis Lambadaris
2024	—	`conf`	Informed Network Routing for SD-WAN enabled SaaS Optimization: An M365 Proof of Concept. CIoT Sai Suchandan Reddy, Nikolai Pitaev, Aris Leivadeas
2024	J	`jnl`	Leveraging Graph Neural Networks for SLA Violation Prediction in Cloud Computing. IEEE Trans. Netw. Serv. Manag. Angelos-Christos Maroudis, Theodoros Theodoropoulos, John Violos, Aris Leivadeas, Konstantinos Tserpes
2024	—	`conf`	Leveraging Light Intensity Structural Breaks for IoT Context-Awareness. WF-IoT John Violos, Konstantinos Stavrianos, Fotios Voutsas, Aris Leivadeas
2024	J	`jnl`	Leveraging pervasive computing for ambient intelligence: A survey on recent advancements, applications and open challenges. Comput. Networks Athanasios Bimpas, John Violos, Aris Leivadeas, Iraklis Varlamis
2024	J	`jnl`	Mitigating Alert Fatigue in Cloud Monitoring Systems: A Machine Learning Perspective. Comput. Networks Fotios Voutsas, John Violos, Aris Leivadeas
2024	—	`conf`	Online VNF Placement using Deep Reinforcement Learning and Reward Constrained Policy Optimization. MeditCom Ramy Mohamed, Marios Avgeris, Aris Leivadeas, Ioannis Lambadaris
2024	J	`jnl`	Service function chain network planning through offline, online and infeasibility restoration techniques. Comput. Networks Ramy Mohamed, Marios Avgeris, Aris Leivadeas, Ioannis Lambadaris, John W. Chinneck, Todd Morris, Petar Djukic
2024	J	`jnl`	VNF Placement and Dynamic NUMA Node Selection Through Core Consolidation at the Edge and Cloud. IEEE Trans. Netw. Serv. Manag. Taha Ben Salah, Marios Avgeris, Aris Leivadeas, Ioannis Lambadaris
2023	—	`conf`	A Brief Review of Population-based Methods for Task Offloading in Cloud-to-Edge Continuum. CloudNet Athanasios Chourlias, Theodoros Theodoropoulos, John Violos, Aris Leivadeas, Konstantinos Tserpes, Christos-Kyprianos Zalachoris
2023	—	`conf`	A Fault Detection Mechanism for Database Management Systems on Mobile Edge Computing. MobileCloud Fotios Voutsas, John Violos, Aris Leivadeas
2023	B	`conf`	A Reinforcement-Learning Self-Healing Approach for Virtual Network Function Placement. NOMS Marios Avgeris, Aris Leivadeas, Ioannis Lambadaris
2023	J	`jnl`	A Survey on Intent-Based Networking. IEEE Commun. Surv. Tutorials Aris Leivadeas, Matthias Falkner
2023	C	`conf`	A Two-Stage Cooperative Reinforcement Learning Scheme for Energy-Aware Computational Offloading. HPSR Marios Avgeris, Meriem Mechennef, Aris Leivadeas, Ioannis Lambadaris
2023	B	`conf`	Analyzing the Performance of SD-WAN Enabled Service Function Chains Across the Globe with AWS. ICPE Aris Leivadeas, Nikolai Pitaev, Matthias Falkner
2023	—	`conf`	Automatic Feasibility Restoration for 5G Cloud Gaming. ICC Ramy Mohamed, Ioannis Lambadaris, Aris Leivadeas, John W. Chinneck, Todd Morris, Petar Djukic
2023	B	`conf`	Autonomous Network Assurance in Intent Based Networking: Vision and Challenges. ICCCN Aris Leivadeas, Matthias Falkner
2023	J	`jnl`	Edge-cloud online joint placement of Virtual Network Functions and allocation of compute and network resources using meta-heuristics. J. Ambient Intell. Humaniz. Comput. Laaziz Lahlou, Chafika Tata, Nadjia Kara, Aris Leivadeas, Abdelouahed Gherbi
2023	J	`jnl`	Enabling Artificial Intelligent Virtual Sensors in an IoT Environment. Sensors Georgios Stavropoulos, John Violos, Stylianos Tsanakas, Aris Leivadeas
2023	—	`conf`	Enhancing Virtual Sensors to deal with Missing Values and Low Sampling Rates. MobileCloud Georgios Anagnostopoulos, Georgios Stavropoulos, John Violos, Aris Leivadeas, Iraklis Varlamis
2023	J	`jnl`	Intelligent Proactive Fault Tolerance at the Edge through Resource Usage Prediction. CoRR Theodoros Theodoropoulos, John Violos, Stylianos Tsanakas, Aris Leivadeas, Konstantinos Tserpes, Theodora A. Varvarigou
2023	C	`conf`	Intent Expression Through Natural Language Processing in an Enterprise Network. HPSR Elie El-Rif, Aris Leivadeas, Matthias Falkner
2023	B	`conf`	Model Predictive Control for Automated Network Assurance in Intent-Based Networking enabled Service Function Chains. NOMS Marios Avgeris, Aris Leivadeas, Nikolaos Athanasopoulos, Ioannis Lambadaris, Matthias Falkner
2023	J	`jnl`	Multi-resource predictive workload consolidation approach in virtualized environments. Comput. Networks Mirna Awad, Aris Leivadeas, Abir Awad
2023	A	`ed.`	Proceedings of the 2023 ACM on Internet Measurement Conference, IMC 2023, Montreal, QC, Canada, October 24-26, 2023 IMC Marie-José Montpetit, Aris Leivadeas, Steve Uhlig, Mobin Javed
2023	—	`conf`	Reinforcement Learning-enabled Auctions for Self-Healing in Service Function Chaining. ICC Workshops Marios Avgeris, Aris Leivadeas, Ioannis Lambadaris
2023	B	`conf`	Service Function Chaining in LEO Satellite Networks via Multi-Agent Reinforcement Learning. GLOBECOM Khai Doan, Marios Avgeris, Aris Leivadeas, Ioannis Lambadaris, Wonjae Shin
2023	J	`jnl`	Toward Intent-Based Network Automation for Smart Environments: A Healthcare 4.0 Use Case. IEEE Access Yosra Njah, Aris Leivadeas, John Violos, Matthias Falkner
2022	J	`jnl`	A Deep Learning Approach for IoT Traffic Multi-Classification in a Smart-City Scenario. IEEE Access Aroosa Hameed, John Violos, Aris Leivadeas
2022	B	`conf`	An IoT-Aware VNF Placement Proof of Concept in a Hybrid Edge-Cloud Smart City Environment. WCNC Yousef Rafique, Aris Leivadeas, Mohamed Ibnkahla
2022	—	`conf`	An Unsupervised Machine Learning Approach for IoT Device Categorization. MeditCom Faïçal Sawadogo, John Violos, Aroosa Hameed, Aris Leivadeas
2022	—	`conf`	Benchmarking Real-time Image Processing for OffLoading at the Edge. MeditCom Olivier Brochu, Dimitrios Spatharakis, Dimitrios Dechouniotis, Aris Leivadeas, Symeon Papavassiliou
2022	—	`conf`	Computational Offloading for the Industrial Internet of Things: A Performance Analysis. MeditCom Sirine Bouhoula, Marios Avgeris, Aris Leivadeas, Ioannis Lambadaris
2022	J	`jnl`	ENERDGE: Distributed Energy-Aware Resource Allocation at the Edge. Sensors Marios Avgeris, Dimitrios Spatharakis, Dimitrios Dechouniotis, Aris Leivadeas, Vasileios Karyotis, Symeon Papavassiliou
2022	J	`jnl`	Intelligent Horizontal Autoscaling in Edge Computing using a Double Tower Neural Network. Comput. Networks John Violos, Stylianos Tsanakas, Theodoros Theodoropoulos, Aris Leivadeas, Konstantinos Tserpes, Theodora A. Varvarigou
2022	J	`jnl`	Intent Based Networking management with conflict detection and policy resolution in an enterprise network. Comput. Networks Xiaoang Zheng, Aris Leivadeas, Matthias Falkner
2022	—	`conf`	Mining News Data for Peripheral Culture Training in AGI. MeditCom Nicholas Dmytryk, Aris Leivadeas
2022	—	`conf`	Online and Scalable Virtual Network Functions Chain Placement for Emerging 5G Networks. MeditCom Ramy Mohamed, Aris Leivadeas, Ioannis Lambadaris, Todd Morris, Petar Djukic
2022	J	`jnl`	Toward QoS Prediction Based on Temporal Transformers for IoT Applications. IEEE Trans. Netw. Serv. Manag. Aroosa Hameed, John Violos, Aris Leivadeas, Nina Santi, Rémy Grünblatt, Nathalie Mitton
2022	J	`jnl`	Utilization prediction-based VM consolidation approach. J. Parallel Distributed Comput. Mirna Awad, Nadjia Kara, Aris Leivadeas
2021	—	`ed.`	13th IFIP Wireless and Mobile Networking Conference, WMNC 2021, Montreal, QC, Canada, October 20-22, 2021 WMNC Leïla Azouz Saïdane, Mohamed Faten Zhani, Aris Leivadeas, Weverton Cordeiro, Eirini-Eleni Tsiropoulou, Thi Mai Trang Nguyen
2021	—	`conf`	A Machine Learning Regression Approach for Throughput Estimation in an IoT Environment. iThings/GreenCom/CPSCom/SmartData/Cybermatics Aroosa Hameed, John Violos, Nina Santi, Aris Leivadeas, Nathalie Mitton
2021	—	`conf`	An Innovative Neuro-Genetic Algorithm and Geometric Loss Function for Mobility Prediction. MobiWac Stylianos Tsanakas, Aroosa Hameed, John Violos, Aris Leivadeas
2021	—	`conf`	Automated and Reproducible Application Traces Generation for IoT Applications. Q2SWinet Nina Santi, Rémy Grünblatt, Brandon Foubert, Aroosa Hameed, John Violos, Aris Leivadeas, Nathalie Mitton
2021	C	`conf`	Hypertuming GRU Neural Networks for Edge Resource Usage Prediction. ISCC John Violos, Stylianos Tsanakas, Theodoros Theodoropoulos, Aris Leivadeas, Konstantinos Tserpes, Theodora A. Varvarigou
2021	—	`conf`	Impact of CPU and Memory Resource Allocation in a Multi-Feature VNF Deployment. MeditCom Sandra Nguemmegne Tumchou, Aris Leivadeas, Matthias Falkner, Nikolai Pitaev
2021	B	`conf`	Network Assurance in Intent-Based Networking Data Centers with Machine Learning Techniques. CNSM Xiaoang Zheng, Aris Leivadeas
2021	J	`jnl`	Task offloading in Edge and Cloud Computing: A survey on mathematical, artificial intelligence and control theory solutions. Comput. Networks Firdose Saeik, Marios Avgeris, Dimitrios Spatharakis, Nina Santi, Dimitrios Dechouniotis, John Violos, Aris Leivadeas, Nikolaos Athanasopoulos, Nathalie Mitton, Symeon Papavassiliou
2021	—	`conf`	User Association and Behavioral Characterization during Task Offloading at the Edge. MeditCom Firdose Saeik, John Violos, Aris Leivadeas, Marios Avgeris, Dimitrios Spatharakis, Dimitrios Dechouniotis
2021	B	`conf`	VAPNIC: A VersAtile shortest path-free VNF Placement using a divide-and-coNquer tactIC. GLOBECOM Laaziz Lahlou, Arol Gbeto Fia, Nadjia Kara, Aris Leivadeas
2021	Misc	`conf`	VNF Placement Problem: A Multi-Tenant Intent-Based Networking Approach. ICIN Aris Leivadeas, Matthias Falkner
2021	—	`conf`	Virtual Sensing Networks and Dynamic RPL-Based Routing for IoT Sensing Services. ICC Ismael Al-Shiab, Aris Leivadeas, Mohamed Ibnkahla
2020	—	`conf`	A Data-Driven Learning System Based on Natural Intelligence for an IoT Virtual Assistant. CAMAD Nicholas Dmytryk, Aris Leivadeas
2020	C	`conf`	Analyzing Service Chaining of Virtualized Network Functions with SR-IOV. HPSR Aris Leivadeas, Matthias Falkner, Nikolai Pitaev
2020	J	`jnl`	Edge Computing Resource Allocation for Dynamic Networks: The DRUID-NET Vision and Perspective. Sensors Dimitrios Dechouniotis, Nikolaos Athanasopoulos, Aris Leivadeas, Nathalie Mitton, Raphaël M. Jungers, Symeon Papavassiliou
2020	—	`conf`	From IoT to Cloud: An End-to-End Virtualization Approach. ECC Aris Leivadeas
2020	—	`conf`	IoT Traffic Multi-Classification Using Network and Statistical Features in a Smart Environment. CAMAD Aroosa Hameed, Aris Leivadeas
2020	J	`jnl`	VNF Chaining Performance Characterization under Multi-Feature and Oversubscription Using SR-IOV. Informatics Asma Ben Hamed, Aris Leivadeas, Matthias Falkner, Nikolai Pitaev
2019	J	`jnl`	VNF Placement Optimization at the Edge and Cloud Future Internet Aris Leivadeas, George Kesidis, Mohamed Ibnkahla, Ioannis Lambadaris
2018	—	`conf`	Analyzing the Coexistence of Wi-Fi and LAA-LTE Towards a Proportional Throughput Fairness. MobiWac Aliasghar Keyhanian, Aris Leivadeas, Ioannis Lambadaris, Ioannis Marmokos
2018	B	`conf`	Balancing Delay and Cost in Virtual Network Function Placement and Chaining. NetSoft Aris Leivadeas, Matthias Falkner, Ioannis Lambadaris, Mohamed Ibnkahla, George Kesidis
2018	B	`conf`	Characterizing the Performance of Concurrent Virtualized Network Functions with OVS-DPDK, FD.IO VPP and SR-IOV. ICPE Nikolai Pitaev, Matthias Falkner, Aris Leivadeas, Ioannis Lambadaris
2018	B	`conf`	Considerations for a Successful Network Service Chain Deployment. NetSoft Aris Leivadeas, Matthias Falkner, Ioannis Lambadaris, George Kesidis, Chung-Horng Lung, Mohamed Ibnkahla
2018	—	`conf`	Link Adaptation for Fair Coexistence of Wi-Fi and LAA-LTE. MobiWac Aris Leivadeas, Thomas Y. Nilsson, Aroosh Elahi, Aliasghar Keyhanian, Ioannis Lambadaris
2017	J	`jnl`	A Graph Partitioning Game Theoretical Approach for the VNF Service Chaining Problem. IEEE Trans. Netw. Serv. Manag. Aris Leivadeas, George Kesidis, Matthias Falkner, Ioannis Lambadaris
2017	B	`conf`	Multi-VNF performance characterization for virtualized network functions. NetSoft Nikolai Pitaev, Matthias Falkner, Aris Leivadeas, Ioannis Lambadaris
2017	J	`jnl`	Optimal virtualized network function allocation for an SDN enabled cloud. Comput. Stand. Interfaces Aris Leivadeas, Matthias Falkner, Ioannis Lambadaris, George Kesidis
2016	—	`conf`	Dynamic traffic steering of multi-tenant virtualized network functions in SDN enabled data centers. CAMAD Aris Leivadeas, Matthias Falkner, Ioannis Lambadaris, George Kesidis
2016	—	`conf`	Dynamic virtualized network function allocation in a multi-cloud environment. ICT Aris Leivadeas, Matthias Falkner, Ioannis Lambadaris, George Kesidis
2016	—	`conf`	Performance analysis of virtualized network functions on virtualized systems architectures. CAMAD Matthias Falkner, Aris Leivadeas, Ioannis Lambadaris, George Kesidis
2016	B	`conf`	Resource Management and Orchestration for a Dynamic Service Chain Steering Model. GLOBECOM Aris Leivadeas, Matthias Falkner, Ioannis Lambadaris, George Kesidis
2015	J	`jnl`	Resource discovery and allocation for federated virtualized infrastructures. Future Gener. Comput. Syst. Chariklis Pittaras, Chrysa Papagianni, Aris Leivadeas, Paola Grosso, Jeroen van der Ham, Symeon Papavassiliou
2014	—	`conf`	Demonstration of a social aware wireless content delivery paradigm. INFOCOM Workshops Aris Leivadeas, Chrysa Papagianni, Symeon Papavassiliou
2014	J	`jnl`	SAViNE: social network analysis - inspired content delivery network deployment and experimentation. EURASIP J. Wirel. Commun. Netw. Aris Leivadeas, Chrysa Papagianni, Symeon Papavassiliou
2013	J	`jnl`	A Cloud-Oriented Content Delivery Network Paradigm: Modeling and Assessment. IEEE Trans. Dependable Secur. Comput. Chrysa Papagianni, Aris Leivadeas, Symeon Papavassiliou
2013	J	`jnl`	Efficient Resource Mapping Framework over Networked Clouds via Iterated Local Search-Based Request Partitioning. IEEE Trans. Parallel Distributed Syst. Aris Leivadeas, Chrysa Papagianni, Symeon Papavassiliou
2013	B	`conf`	Energy Aware Networked Cloud Mapping. NCA Aris Leivadeas, Chrysa Papagianni, Symeon Papavassiliou
2013	J	`jnl`	On the Optimal Allocation of Virtual Resources in Cloud Computing Networks. IEEE Trans. Computers Chrysa Papagianni, Aris Leivadeas, Symeon Papavassiliou, Vasilis Maglaris, Cristina Cervello-Pastor, Álvaro Monje
2012	J	`jnl`	Socio-aware virtual network embedding. IEEE Netw. Aris Leivadeas, Chrysa Papagianni, Symeon Papavassiliou
2011	—	`conf`	An Architecture for Virtual Network Embedding in Wireless Systems. NCCA Aris Leivadeas, Chrysa Papagianni, Evripidis Paraskevas, Georgios Androulidakis, Symeon Papavassiliou