Lazaros Karagiannidis

Mr. Lazaros Karagiannidis

orcid

Research Focus & Metrics

Academic Career Length

10Years (2017-Present)

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

Representative Publications

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1 June 2018 in Journal of Environmental Management
Verified
Journal Article
Closed access
CMChristos Makropoulos
Christos Makropoulos
Evangelos RozosEvangelos Rozos
Evangelos Rozos
ITIoannis Tsoukalas
Ioannis Tsoukalas
APA. Plevri
A. Plevri
GKG. Karakatsanis
G. Karakatsanis
ELE. Lytras
E. Lytras

6 March 2022 in Sensors
Verified
Journal Article
Open access
PDF file
ADAthanasios Douklias
Athanasios Douklias
LKLazaros Karagiannidis
Lazaros Karagiannidis
FMFay Misichroni
Fay Misichroni
Angelos AmditisAngelos Amditis
Angelos Amditis
Visual sensing of the environment is crucial for flying an unmanned aerial vehicle (UAV) and is a centerpiece of many related applications. The ability to run computer vision and machine learning algorithms onboard an unmanned aerial system (UAS) is becoming more of a necessity in an effort to alleviate the communication burden of high-resolution video streaming, to provide flying aids, such as obstacle avoidance and automated landing, and to create autonomous machines. Thus, there is a growing interest on the part of many researchers in developing and validating solutions that are suitable for deployment on a UAV system by following the general trend of edge processing and airborne computing, which transforms UAVs from moving sensors into intelligent nodes that are capable of local processing. In this paper, we present, in a rigorous way, the design and implementation of a 12.85 kg UAV system equipped with the necessary computational power and sensors to serve as a testbed for image processing and machine learning applications, explain the rationale behind our decisions, highlight selected implementation details, and showcase the usefulness of our system by providing an example of how a sample computer vision application can be deployed on our platform.

24 March 2022 in Information
Verified
Journal Article
Open access
PDF file
EMEvangelos Maltezos
Evangelos Maltezos
KPKonstantinos Petousakis
Konstantinos Petousakis
ADAris Dadoukis
Aris Dadoukis
LKLazaros Karagiannidis
Lazaros Karagiannidis
Eleftherios OuzounoglouEleftherios Ouzounoglou
Eleftherios Ouzounoglou
Angelos AmditisAngelos Amditis
Angelos Amditis
Nowadays, the transformations of cities into smart cities is a crucial factor in improving the living conditions of the inhabitants as well as addressing emergency situations under the concept of public safety and property loss. In this context, many sensing systems have been designed and developed that provide fire detection and gas leakage alerts. On the other hand, new technologies such edge computing have gained significant attention in recent years. Moreover, the development of recent intelligent applications in IoT aims to integrate several types of systems with automated next-generation emergency calls in case of a serious accident. Currently, there is a lack of studies that combine all the aforementioned technologies. The proposed smart building sensor system, SB112, combines a small-size multisensor-based (temperature, humidity, smoke, flame, CO, LPG, and CNG) scheme with an open-source edge computing framework and automated Next Generation (NG) 112 emergency call functionality. It involves crucial actors such as IoT devices, a Public Safety Answering Point (PSAP), the middleware of a smart city platform, and relevant operators in an end-to-end manner for real-world scenarios. To verify the utility and functionality of the proposed system, a representative end-to-end experiment was performed, publishing raw measurements from sensors as well as a fire alert in real time and with low latency (average latency of 32 ms) to the middleware of a smart city platform. Once the fire was detected, a fully automatic NG112 emergency call to a PSAP was performed. The proposed methodology highlights the potential of the SΒ112 system for exploitation by decision-makers or city authorities.

25 February 2022 in Computation
Verified
Journal Article
Open access
PDF file
EMEvangelos Maltezos
Evangelos Maltezos
PLPanagiotis Lioupis
Panagiotis Lioupis
ADAris Dadoukis
Aris Dadoukis
LKLazaros Karagiannidis
Lazaros Karagiannidis
Eleftherios OuzounoglouEleftherios Ouzounoglou
Eleftherios Ouzounoglou
Angelos AmditisAngelos Amditis
Angelos Amditis
Ensuring citizens’ safety and security has been identified as the number one priority for city authorities when it comes to the use of smart city technologies. Automatic understanding of the scene, and the associated provision of situational awareness for emergency situations, are able to efficiently contribute to such domains. In this study, a Video Analytics Edge Computing (VAEC) system is presented that performs real-time enhanced situation awareness for person detection in a video surveillance manner that is also able to share geolocated person detection alerts and other accompanied crucial information. The VAEC system adopts state-of-the-art object detection and tracking algorithms, and it is integrated with the proposed Distribute Edge Computing Internet of Things (DECIoT) platform. The aforementioned alerts and information are able to be shared, though the DECIoT, to smart city platforms utilizing proper middleware. To verify the utility and functionality of the VAEC system, extended experiments were performed (i) in several light conditions, (ii) using several camera sensors, and (iii) in several use cases, such as installed in fixed position of a building or mounted to a car. The results highlight the potential of VAEC system to be exploited by decision-makers or city authorities, providing enhanced situational awareness.

15 March 2022 in Computation
Verified
Journal Article
Open access
PDF file
EVEmmanuel Vasilopoulos
Emmanuel Vasilopoulos
GVGeorgios Vosinakis
Georgios Vosinakis
MKMaria Krommyda
Maria Krommyda
LKLazaros Karagiannidis
Lazaros Karagiannidis
Eleftherios OuzounoglouEleftherios Ouzounoglou
Eleftherios Ouzounoglou
Angelos AmditisAngelos Amditis
Angelos Amditis
Maritime operations rely heavily on surveillance and require reliable and timely data that can inform decisions and planning. Critical information in such cases includes the exact location of objects in the water, such as vessels, persons, and others. Due to the unique characteristics of the maritime environment, the location of even inert objects changes through time, depending on the weather conditions, water currents, etc. Unmanned aerial vehicles (UAVs) can be used to support maritime operations by providing live video streams and images from the area of operations. Machine learning algorithms can be developed, trained, and used to automatically detect and track objects of specific types and characteristics. EFFECTOR is an EU-funded project, developing an Interoperability Framework for maritime surveillance. Within the project, we developed an embedded system that employs machine learning algorithms, allowing a UAV to autonomously detect objects in the water and keep track of their changing position through time. Using the on-board computation unit of the UAV, we ran and present the results of a series of comparative tests among possible architecture sizes and training datasets for the detection and tracking of objects in the maritime environment. We tested architectures based on their efficiency, accuracy, and speed. A combined solution for training the datasets is suggested, providing optimal efficiency and accuracy.

29 January 2021 in Computation
Verified
Journal Article
Open access
PDF file
EMEvangelos Maltezos
Evangelos Maltezos
ADAthanasios Douklias
Athanasios Douklias
ADAris Dadoukis
Aris Dadoukis
FMFay Misichroni
Fay Misichroni
LKLazaros Karagiannidis
Lazaros Karagiannidis
Angelos AmditisAngelos Amditis
Angelos Amditis
Situational awareness is a critical aspect of the decision-making process in emergency response and civil protection and requires the availability of up-to-date information on the current situation. In this context, the related research should not only encompass developing innovative single solutions for (real-time) data collection, but also on the aspect of transforming data into information so that the latter can be considered as a basis for action and decision making. Unmanned systems (UxV) as data acquisition platforms and autonomous or semi-autonomous measurement instruments have become attractive for many applications in emergency operations. This paper proposes a multipurpose situational awareness platform by exploiting advanced on-board processing capabilities and efficient computer vision, image processing, and machine learning techniques. The main pillars of the proposed platform are: (1) a modular architecture that exploits unmanned aerial vehicle (UAV) and terrestrial assets; (2) deployment of on-board data capturing and processing; (3) provision of geolocalized object detection and tracking events; and (4) a user-friendly operational interface for standalone deployment and seamless integration with external systems. Experimental results are provided using RGB and thermal video datasets and applying novel object detection and tracking algorithms. The results show the utility and the potential of the proposed platform, and future directions for extension and optimization are presented.