Ioannis Kompatsiaris

Dr. Ioannis Kompatsiaris

CERTH - Information Technologies Institute
orcid

Research Focus & Metrics

Academic Career Length

29Years (1998-Present)

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

Representative Publications

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3 February 2020 in WIREs Data Mining and Knowledge Discovery
Verified
Journal Article
Open access
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ENEirini Ntoutsi
Eirini Ntoutsi
PFPavlos Fafalios
Pavlos Fafalios
UGUjwal Gadiraju
Ujwal Gadiraju
VIVasileios Iosifidis
Vasileios Iosifidis
WNWolfgang Nejdl
Wolfgang Nejdl
SSSteffen Staab
Steffen Staab
Artificial Intelligence (AI)‐based systems are widely employed nowadays to make decisions that have far‐reaching impact on individuals and society. Their decisions might affect everyone, everywhere, and anytime, entailing concerns about potential human rights issues. Therefore, it is necessary to move beyond traditional AI algorithms optimized for predictive performance and embed ethical and legal principles in their design, training, and deployment to ensure social good while still benefiting from the huge potential of the AI technology. The goal of this survey is to provide a broad multidisciplinary overview of the area of bias in AI systems, focusing on technical challenges and solutions as well as to suggest new research directions towards approaches well‐grounded in a legal frame. In this survey, we focus on data‐driven AI, as a large part of AI is powered nowadays by (big) data and powerful machine learning algorithms. If otherwise not specified, we use the general term bias to describe problems related to the gathering or processing of data that might result in prejudiced decisions on the bases of demographic features such as race, sex, and so forth.This article is categorized under: Commercial, Legal, and Ethical Issues > Fairness in Data Mining Commercial, Legal, and Ethical Issues > Ethical Considerations Commercial, Legal, and Ethical Issues > Legal Issues

14 June 2011 in Data Mining and Knowledge Discovery
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Journal Article
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Symeon PapadopoulosSymeon Papadopoulos
Symeon Papadopoulos
Ioannis KompatsiarisIoannis Kompatsiaris
Ioannis Kompatsiaris
AVAthena Vakali
Athena Vakali
PSPloutarchos Spyridonos
Ploutarchos Spyridonos

6 June 2013 in IEEE Transactions on Multimedia
Verified
Journal Article
Closed access
LALuca Maria Aiello
Luca Maria Aiello
GPGeorgios Petkos
Georgios Petkos
CMCarlos Martin
Carlos Martin
DCDavid Corney
David Corney
Symeon PapadopoulosSymeon Papadopoulos
Symeon Papadopoulos
AJAlejandro Jaimes
Alejandro Jaimes
Online social and news media generate rich and timely information about real-world events of all kinds. However, the huge amount of data available, along with the breadth of the user base, requires a substantial effort of information filtering to successfully drill down to relevant topics and events. Trending topic detection is therefore a fundamental building block to monitor and summarize information originating from social sources. There are a wide variety of methods and variables and they greatly affect the quality of results. We compare six topic detection methods on three Twitter datasets related to major events, which differ in their time scale and topic churn rate. We observe how the nature of the event considered, the volume of activity over time, the sampling procedure and the pre-processing of the data all greatly affect the quality of detected topics, which also depends on the type of detection method used. We find that standard natural language processing techniques can perform well for social streams on very focused topics, but novel techniques designed to mine the temporal distribution of concepts are needed to handle more heterogeneous streams containing multiple stories evolving in parallel. One of the novel topic detection methods we propose, based on -grams cooccurrence and topic ranking, consistently achieves the best performance across all these conditions, thus being more reliable than other state-of-the-art techniques.

16 May 2020 in Sensors
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Journal Article
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Thanos StavropoulosThanos Stavropoulos
Thanos Stavropoulos
APAsterios Papastergiou
Asterios Papastergiou
Lampros MpaltadorosLampros Mpaltadoros
Lampros Mpaltadoros
Spiros NikolopoulosSpiros Nikolopoulos
Spiros Nikolopoulos
Ioannis KompatsiarisIoannis Kompatsiaris
Ioannis Kompatsiaris
The increasing ageing global population is causing an upsurge in ailments related to old age, primarily dementia and Alzheimer’s disease, frailty, Parkinson’s, and cardiovascular disease, but also a general need for general eldercare as well as active and healthy ageing. In turn, there is a need for constant monitoring and assistance, intervention, and support, causing a considerable financial and human burden on individuals and their caregivers. Interconnected sensing technology, such as IoT wearables and devices, present a promising solution for objective, reliable, and remote monitoring, assessment, and support through ambient assisted living. This paper presents a review of such solutions including both earlier review studies and individual case studies, rapidly evolving in the last decade. In doing so, it examines and categorizes them according to common aspects of interest such as health focus, from specific ailments to general eldercare; IoT technologies, from wearables to smart home sensors; aims, from assessment to fall detection and indoor positioning to intervention; and experimental evaluation participants duration and outcome measures, from acceptability to accuracy. Statistics drawn from this categorization aim to outline the current state-of-the-art, as well as trends and effective practices for the future of effective, accessible, and acceptable eldercare with technology.

26 July 2019 in Remote Sensing
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Journal Article
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MKMarios Krestenitis
Marios Krestenitis
GOGeorgios Orfanidis
Georgios Orfanidis
Konstantinos IoannidisKonstantinos Ioannidis
Konstantinos Ioannidis
KAKonstantinos Avgerinakis
Konstantinos Avgerinakis
Stefanos VrochidisStefanos Vrochidis
Stefanos Vrochidis
Ioannis KompatsiarisIoannis Kompatsiaris
Ioannis Kompatsiaris
Oil spill is considered one of the main threats to marine and coastal environments. Efficient monitoring and early identification of oil slicks are vital for the corresponding authorities to react expediently, confine the environmental pollution and avoid further damage. Synthetic aperture radar (SAR) sensors are commonly used for this objective due to their capability for operating efficiently regardless of the weather and illumination conditions. Black spots probably related to oil spills can be clearly captured by SAR sensors, yet their discrimination from look-alikes poses a challenging objective. A variety of different methods have been proposed to automatically detect and classify these dark spots. Most of them employ custom-made datasets posing results as non-comparable. Moreover, in most cases, a single label is assigned to the entire SAR image resulting in a difficulties when manipulating complex scenarios or extracting further information from the depicted content. To overcome these limitations, semantic segmentation with deep convolutional neural networks (DCNNs) is proposed as an efficient approach. Moreover, a publicly available SAR image dataset is introduced, aiming to consist a benchmark for future oil spill detection methods. The presented dataset is employed to review the performance of well-known DCNN segmentation models in the specific task. DeepLabv3+ presented the best performance, in terms of test set accuracy and related inference time. Furthermore, the complex nature of the specific problem, especially due to the challenging task of discriminating oil spills and look-alikes is discussed and illustrated, utilizing the introduced dataset. Results imply that DCNN segmentation models, trained and evaluated on the provided dataset, can be utilized to implement efficient oil spill detectors. Current work is expected to contribute significantly to the future research activity regarding oil spill identification and SAR image processing.

1 September 2016 in Multimedia Tools and Applications
Verified
Journal Article
Closed access
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MZMarkos Zampoglou
Markos Zampoglou
Symeon PapadopoulosSymeon Papadopoulos
Symeon Papadopoulos
Ioannis KompatsiarisIoannis Kompatsiaris
Ioannis Kompatsiaris