Symeon Papavassiliou's research while affiliated with National Technical University of Athens and other places

Publications (440)

Conference Paper
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The fifth-generation (5G) mobile communications promise far more capabilities than competing technologies and are expected to enable a wide range of vertical use cases. Among them, remote driving has attracted much interest from both academia and the industry, either as a stepping stone on the road to fully autonomous driving or as its complement c...
Conference Paper
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The Minimum Collisions Assignment in an interdependent networked system is the problem of assigning a finite set of resources over the nodes of the network, such that the number of collisions, i.e., the number of interdependent nodes receiving the same resource, is minimized. It has been shown in the literature that, when the number of resources is...
Article
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The development of solutions to manage or mitigate climate change impacts is very challenging, given the complexity and dynamicity of the socio-environmental and socio-ecological systems that have to be modeled and analyzed, and the need to include qualitative variables that are not easily quantifiable. The existence of qualitative, interoperable a...
Conference Paper
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The development of a supportive school climate within classrooms can provide new opportunities for enhancing children's academic and social outcomes. Τo facilitate the success of inclusion, it is necessary that all students develop the skills to understand each other, communicate and work together effectively. Nowadays, even if various research out...
Conference Paper
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An effective way to accommodate the computing demands of Internet-of-Things (IoT) end-user devices without the intervention of a remote server, is to motivate the collaboration between them. The latter paradigm, termed as collaborative Mobile Edge Computing (MEC), allows an end-user device to act as service provider, by allocating excess computing...
Article
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In this paper, we study the potential of using the metric of Age of Information (AoI) for enhancing delay-tolerant routing protocols. The latter have been proposed for alleviating the impact of long roundtrip time in networks operating in harsh environments, e.g., in distributed applications deployed in a desert/sparsely populated area without infr...
Article
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In the dawn of the 6G era, evolving service ecosystems raise the need for cross-service interactions. Existing resource/service orchestration frameworks are oblivious to such cross-service interactions, since they tend to orchestrate services independent to each other. In this respect, we stress on the need for optimized crossservice communication,...
Conference Paper
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The emergence of Industrial Internet of Things (IIoT) requires the interconnection between robots, sensors, and the underlying network and computing infrastructure. Edge Robotics has emerged as a flexible paradigm that enables resource-constrained mobile robots to offload computationally intensive tasks of time/mission-critical applications. In thi...
Article
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Nowadays, various frameworks are emerging for supporting distributed tracing techniques over microservices-based distributed applications. The objective is to improve observability and management of operational problems of distributed applications, considering bottlenecks in terms of high latencies in the interaction among the deployed microservice...
Article
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The edge computing paradigm has become extremely popular over the past years, as a means of offloading computationally intensive tasks by users of resource and battery-constrained devices. Nevertheless, the edge networks' overexploitation by the ever-increasing number of task-offloading users, gradually leads to their performance degradation. In th...
Article
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This paper focuses on the design, implementation, experimental validation, and evaluation of a network tomography approach for performing inferential monitoring based on indirect measurements. In particular, we address the problems of inferring the routing tree topology (both logical and physical) and estimating the links’ loss rate and jitter base...
Article
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Mobile applications are progressively becoming more sophisticated and complex, increasing their computational requirements. Traditional offloading approaches that use exclusively the Cloud infrastructure are now deemed unsuitable due to the inherent associated delay. Edge Computing can address most of the Cloud limitations at the cost of limited av...
Article
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The evolution of the Industrial Internet of Things (IIoT) and Edge Computing enables resource-constrained mobile robots to offload the computationally intensive localization algorithms. Naturally, utilizing the remote resources of an edge server to offload these tasks, encounters the challenge of a joint co-design in communication, control, estimat...
Article
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The ongoing transition towards 5G technology expedites the emergence of a variety of mobile applications that pertain to different vertical industries. Delivering on the key commitment of 5G, these diverse service streams, along with their distinct requirements, should be facilitated under the same unified network infrastructure. Consequently, in o...
Article
Serverless computing is emerging as a cloud computing paradigm that provisions computing resources on demand, while billing is taking place based on the exact usage of the cloud resources. The responsibility for infrastructure management is undertaken by cloud providers, enabling developers to focus on the development of the business logic of their...
Article
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The proliferation of multiaccess edge computing (MEC) paradigm has created a challenging multiuser–multiserver–multiaccess edge computing competitive environment, which brings the problem of data offloading decision-making to the forefront of research. In this article, we address this issue while jointly studying the impact of the user behavioral c...
Article
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In this article, we address the problem of modeling and orchestrating the interactions between a museum and its visitors, viewing the system as a cyber–physical–social system (CPSS). In particular, the museum operator provides monetary rewards to the visitors in exchange for their contributions, which are expressed as their total number of provided...
Article
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Significant efforts have been allocated over the last thirty years towards the conceptualization and assessment of the Emotional Intelligence (EI) construct. However, there is limited work on examining the EI construct in a group level. Collective Emotional Intelligence (CEI) is introduced as the ability of a group to promote awareness and regulati...
Conference Paper
In this paper, a vision for beyond-5G systems is proposed where automation and intelligence in cloud-native infrastructures are in focus. Exploiting the convergence of cloud technologies at the edge and mobile communication networks, a set of technological solutions is discussed that will play a fundamental role on the path from 5G towards future 6...
Conference Paper
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By considering the dynamicity and complexity that is present in modern Socio-Environmental Systems along with the misalignment in the usage of terms that are used by scientists in different disciplines, there is a need to support new ways of modelling and analysis based on the establishment of synergies and the collaboration among scientists. To ad...
Article
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A Fragile CPR Game is an instance of a resource sharing game where a common-pool resource, which is prone to failure due to overuse, is shared among several players. Each player has a fixed initial endowment and is faced with the task of investing in the common-pool resource without forcing it to fail. The return from the common-pool resource is su...
Article
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The Integrated Access and Backhaul (IAB) technology provides a new view of the backhauling problem, especially when targeting end-to-end service provisioning. The IAB paradigm -being well aligned with the vision of Unmanned Aerial Vehicles (UAVs) -when combined with the benefits of the Reconfigurable Intelligent Surface (RIS) technology, offers to...
Conference Paper
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To support the provisioning of modern services in a smart city environment, future communication networks need to be intelligently designed with respect to the city infrastructure and energy efficient utilization of resources. Unmanned Aerial Vehicles (UAVs) are already being utilized as part of a smart city wireless network infrastructure to provi...
Article
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The evolution of 5G network service ecosystems raises the need for the discovery of services among multiple (edge) clouds with potentially heterogeneous resources and features. Besides 5G service deployment, such a service discovery architecture could provide the means for cross-service communication (CSC), that is, the consumption of a network ser...
Conference Paper
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Recently, non-orthogonal multiple access (NOMA) small cell networks (SCNs) have been studied to meet the stringent requirements for spectral efficiency and massive connectivity in the emerging 5G networks. This paper aims at addressing the overall resource orchestration issue in 5G SCNs, by considering the problem of joint user to small cell associ...
Conference Paper
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We discuss initial results on a vCDN use case, deployed on top of optiMized Edge Slice OrchestratioN (MESON), which comprises a MANO framework aiming at facilitating optimized cross-slice communications at the network edge.
Conference Paper
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Modern Industry 4.0 applications require the interplay between industrial equipment, robots, and network infrastructure. This article demonstrates the experimental capabilities of the NETMODE testbed, part of the MESON project, on Industry 4.0 and remote driving scenarios.
Conference Paper
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The consolidation of 5G technologies makes the Industry 4.0 establishment more feasible than ever. Network Function Virtualization (NFV) and Edge Computing aim at managing the multi-vendor industrial and network infrastructure and guaranteeing the high-performance requirements of industrial processes. Furthermore, industrial production workflows re...
Conference Paper
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The Fifth Generation (5G) mobile communications together with software defined networking (SDN) and network function virtualization (NFV) are expected to enable a wide range of vertical use-cases. Different vertical industries with diverse service streams and sets of requirements should leverage the advanced capabilities of 5G networks through a si...
Conference Paper
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The emergence of Unmanned Aerial Vehicles (UAVs) as part of the safety-critical and traffic alleviation infrastructure in 5G and beyond wireless networks, promotes the rethinking of the conventional resource orchestration management. In this paper, we propose a novel methodology that treats the uplink power allocation problem in UAV-assisted wirele...
Article
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In this paper, to exploit the challenges and potential offered by the simultaneous use of non-orthogonal multiple access (NOMA) and orthogonal frequency division multiple access (OFDMA) transmission options in future 5G wireless systems, we aim at the proper modeling and transformation of the uplink power allocation problem. In particular, in this...
Preprint
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The network coloring game has been proposed in the literature of social sciences as a model for conflict-resolution circumstances. The players of the game are the vertices of a graph with $n$ vertices and maximum degree $\Delta$. The game is played over rounds, and in each round all players simultaneously choose a color from a set of available colo...
Article
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A smart city represents an improvement of today’s cities, both functionally and structurally, that strategically utilizes several smart factors, capitalizing on Information and Communications Technology (ICT) to increase the city’s sustainable growth and strengthen the city’s functions, while ensuring the citizens’ enhanced quality of life and heal...
Technical Report
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This white paper on AI and ML as enablers of beyond 5G (B5G) networks is based on contributions from 5G PPP projects that research, implement and validate 5G and B5G network systems. The white paper introduces the main relevant mechanisms in Artificial Intelligence (AI) and Machine Learning (ML), currently investigated and exploited for 5G and B5G...
Article
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In this paper we propose a holistic framework that aims at a paradigm shift in the treatment of the uplink power control problem in wireless networks, under the perspective of games in satisfaction form. Novel satisfaction equilibrium points of special interest within the considered problem - such as the Minimum Efficient Satisfaction Equilibrium (...
Article
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Next generation communication networks are expected to accommodate a high number of new and resource-voracious applications that can be offered to a large range of end users. Even though end devices are becoming more powerful, the available local resources cannot cope with the requirements of these applications. This has created a new challenge cal...
Chapter
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Improvement of social and emotional competencies of students is associated with positive effects in various learning and personal development activities. To achieve so, Social and Emotional Learning (SEL) activities are applied by tutors within educational groups. In the current manuscript, we present an approach for composition and analysis of soc...
Article
In this article, we consider the problem of recommendations to the users of an online social network (OSN), through an information diffusion aware recommender system (IDARS). We map the assignment of recommendations in influence networks to a problem of selecting an l -cover of the minimum total cost, which is defined to be a set of assignments s...
Article
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In this paper, the combined problem of power company selection and demand response management (DRM) in a smart grid network consisting of multiple power companies and multiple customers is studied via adopting a reinforcement learning and game-theoretic technique. Each power company is characterized by its reputation and competitiveness. The custom...
Article
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In this paper, a novel data offloading decision-making framework is proposed, where users have the option to partially offload their data to a complex Multi-access Edge Computing (MEC) environment, consisting of both ground and UAV-mounted MEC servers. The problem is treated under the perspective of risk-aware user behavior as captured via prospect...
Article
Efficient monitoring plays a vital role in software-defined networking (SDN)-enabled 5G networks, involving the monitoring of performance metrics for both physical and virtual networks and considering the requirements of a variety of traffic types originating from different applications. However, conventional network monitoring tools based on tradi...
Article
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With the advent of 5G verticals and the Internet of Things paradigm, Edge Computing has emerged as the most dominant service delivery architecture, placing augmented computing resources in the proximity of end users. The resource orchestration of edge clouds relies on the concept of network slicing, which provides logically isolated computing and n...
Preprint
Full-text available
A Fragile CPR Game is an instance of a resource sharing game where a common-pool resource, which is prone to failure due to overuse, is shared among several players. Each player has a fixed initial endowment and is faced with the task of investing in the common-pool resource without forcing it to fail. The return from the common-pool resource is su...
Article
Full-text available
Significant efforts have been allocated over the last thirty years towards the definition and measurement of the Emotional Intelligence (EI) construct. Several EI theories and models have been produced to support psychological assessment processes. However, barriers are identified for their wide adoption and exploitation by social scientists. The a...
Article
In this work, we consider the joint behavior of an information diffusion process integrated with a recommender system (RecSys) over an online social network (OSN), where the typical users' resilience to information varies, leading to potential information overloads. We assume that each user has a threshold over the information that she can process...
Conference Paper
Full-text available
The Internet of Things (IoT) paradigm, with a grand variety of devices in large numbers, commonly combined with resource and power limitations dictates new challenges and constraints. The emerging Edge Computing paradigm arises promises to address these issues by placing cloud-type resources, closer to IoT devices. In this context, network slicing...
Preprint
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Let $\{X_i\}_{i\ge 1}$ be a sequence of independent random variables taking values in the set of non-negative integers and, given $k\ge 1$, set $S_k = X_1+\cdots +X_k$. Fix $k\ge 1$, and let $\alpha_{k+1}>-1$ be a real number such that $\mathbb{E}(X_{k+1})\le 1 + \alpha$. Assume further that there exists a real number $c_k>0$ such that the followin...
Article
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Network slicing is set out to address crucial needs of 5G, including support for multi-service provisioning. Focusing on resource and performance isolation, as well as security concerns associated with multi-tenancy, existing management and orchestration (MANO) frameworks typically offer network slices in the form of isolated bundles of computing,...
Article
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The sheer growth of data traffic and the rising number of connected devices have highlighted and elevated the need of addressing spectral scarcity and enhancing resource utilization in 5G wireless networks. Toward this direction, the overwhelming majority of existing wireless resource management approaches and methodologies aim directly at energy e...