Nikos Kefalakis

Nikos Kefalakis


Research Focus & Metrics

Academic Career Length

12Years (2015-Present)

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

Representative Publications

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11 March 2015
Verified
Book Chapter
Closed access
PDF file
JSJohn Soldatos
John Soldatos
NKNikos Kefalakis
Nikos Kefalakis
MHManfred Hauswirth
Manfred Hauswirth
MSMartin Serrano
Martin Serrano
JCJean-Paul Calbimonte
Jean-Paul Calbimonte
RHReinhard Herzog
Reinhard Herzog

16 January 2015 in IEEE Journal on Selected Areas in Communications
Verified
Journal Article
Closed access
MSMartin Serrano
Martin Serrano
HQHoan Nguyen Mau Quoc
Hoan Nguyen Mau Quoc
DPDanh Le Phuoc
Danh Le Phuoc
MHManfred Hauswirth
Manfred Hauswirth
JSJohn Soldatos
John Soldatos
AZArkady Zaslavsky
Arkady Zaslavsky
This paper introduces the stack for service delivery models and interoperability in the Internet of Things. The main characteristics and functional layers of the IoT stack are described. The applicability of the IoT stack is described based on particular use cases and deployed pilots. The validation of the IoT stack in terms of functionality and adaptation at different IoT particular areas is based on the Virtual Development Kit (VDK) developed and implemented within the framework of the OpenIoT project-OpenIoT project is the awarded Internet of Things open-source rookie of the year by BlackDuck Software Co. (www.github.com/OpenIotOrg). The methods and standards that boosted OpenIoT-VDK implementation are described in this paper. An instance of the OpenIoT-VDK process is described as the practical use case demonstrating being an IoT platform with autonomic behavior. OpenIoT-VDK creates IoT instances, analyzes the IoT stack dependence, and resolves them following interoperability principles. The OpenIoT-VDK instance deploys IoT service delivery models facilitating the validation of use cases by using the OpenIoT platform. As proof of concept, a delivered IoT service using open data from OpenIoT local instantiation is described.

11 March 2015
Verified
Book Chapter
Closed access
PDF file
NKNikos Kefalakis
Nikos Kefalakis
JSJohn Soldatos
John Soldatos
AAAchilleas Anagnostopoulos
Achilleas Anagnostopoulos
PDPanagiotis Dimitropoulos
Panagiotis Dimitropoulos

20 November 2019 in Information
Verified
Journal Article
Open access
PDF file
NKNikos Kefalakis
Nikos Kefalakis
ARAikaterini Roukounaki
Aikaterini Roukounaki
JSJohn Soldatos
John Soldatos
One of the main challenges in modern Internet of Things (IoT) systems is the efficient collection, routing and management of data streams from heterogeneous sources, including sources with high ingestion rates. Despite the existence of various IoT data streaming frameworks, there is still no easy way for collecting and routing IoT streams in efficient and configurable ways that are easy to be implemented and deployed in realistic environments. In this paper, we introduce a programmable engine for Distributed Data Analytics (DDA), which eases the task of collecting IoT streams from different sources and accordingly, routing them to appropriate consumers. The engine provides also the means for preprocessing and analysis of data streams, which are two of the most important tasks in Big Data analytics applications. At the heart of the engine lies a Domain Specific Language (DSL) that enables the zero-programming definition of data routing and preprocessing tasks. This DSL is outlined in the paper, along with the middleware that supports its runtime execution. As part of the paper, we present the architecture of the engine, as well as the digital models that it uses for modelling data streams in the digital world. We also discuss the validation of the DDA in several data intensive IoT use cases in industrial environments, including use cases in pilot productions lines and in several real-life manufacturing environments. The latter manifest the configurability, programmability and flexibility of the DDA engine, as well as its ability to support practical applications.

1 September 2022
Verified
Book Chapter
Open access
PDF file
NKNikos Kefalakis
Nikos Kefalakis
ARAikaterini Roukounaki
Aikaterini Roukounaki
JSJohn Soldatos
John Soldatos
This chapter presents the role and uses of digital models in industrial automation applications of the Industry 4.0 era. Accordingly, it reviews a range of standard-based models for digital automation and their suitability for the tasks of plant modelling and configuration. Finally, the chapter introduces the digital models specified and used in the scope of the FAR-EDGE automation platform, towards supporting digital twins and system configuration use cases.

1 September 2022
Verified
Book Chapter
Open access
PDF file
NKNikos Kefalakis
Nikos Kefalakis
ARAikaterini Roukounaki
Aikaterini Roukounaki
JSJohn Soldatos
John Soldatos
MIMauro Isaja
Mauro Isaja
This chapter presents a dynamic and programmable distributed data analytics solution for industrial environments. The solution includes an edge analytics engine for analytics close to the field and in line with the edge computing paradigm. Each edge analytics engine instance is flexible and dynamically configurable based on an Analytics Manifest (AM). It is also based on distributed ledger technologies for configuring analytics tasks that span multiple edge nodes and instances of the edge analytics engine. In particular, it leverages ledger services for synchronizing and combining various AMs in factory wide analytics tasks. Based on these mechanisms, the presented distributed data analytics infrastructure is therefore flexible, configurable, dynamic and resilient. Moreover, it is open source and provides Open APIs (Application Programming Interfaces) that enable access to its functionalities. These features make it unique and valuable for vendors and integrators of industrial automation solutions.