• Autoregressive energy-efficient context forwarding in wireless sensor networks for pervasive healthcare systems 

      Anagnostopoulos, C.; Hadjiefthymiades, S.; Katsikis, A.; Maglogiannis, I. (2014)
      Driven by technological advances in low-power network systems and medical sensors, we have witnessed during the recent years the adoption of wireless sensor networks (WSNs) in electronic healthcare. Improving the quality ...
    • An efficient Recommendation System based on the Optimal Stopping Theory 

      Kolomvatsos, K.; Anagnostopoulos, C.; Hadjiefthymiades, S. (2014)
      A Recommendation System (RS) aims to deliver meaningful recommendations to users for items (e.g., music and books), which are of high interest to them. We consider an RS which directly communicates with a set of providers ...
    • Enabling Location Privacy and Medical Data Encryption in Patient Telemonitoring Systems 

      Maglogiannis, I.; Kazatzopoulos, L.; Delakouridis, K.; Hadjiefthymiades, S. (2009)
      Patient telemonitoring systems (PTS) deal with the acquisition, processing, and secure transmission of a patient's physiological and physical parameters to a remote location, where expert medical knowledge is available. ...
    • Optimizing pervasive sensor data acquisition utilizing missing values substitution 

      Michalopoulos, M.; Maglogiannis, I.; Anagnostopoulos, C.; Doukas, C.; Hadjiefthymiades, S. (2010)
      Acquisition of pervasive sensor data can be often unsuccessful due to power outage at nodes, time synchronization issues, interference, network transmission failures or sensor hardware issues. Such failures can lead to ...
    • A time optimized scheme for top-k list maintenance over incomplete data streams 

      Kolomvatsos, K.; Anagnostopoulos, C.; Hadjiefthymiades, S. (2015)
      A large number of contemporary research efforts focus on incomplete data streams handling. These efforts, usually, focus on the creation and maintenance of top-k lists useful to provide efficient responses to top-k queries. ...
    • Time-optimized user grouping in Location Based Services 

      Anagnostopoulos, C.; Hadjiefthymiades, S.; Kolomvatsos, K. (2015)
      We focus on Location Based Services (LBSs) which deliver information to groups of mobile users based on their spatial context. The existence (and non-trivial lifetime) of groups of mobile users can simplify the operation ...
    • User modeling for pedestrian navigation services 

      Kikiras, P.; Tsetsos, V.; Papataxiarhis, V.; Katsikas, T.; Hadjiefthymiades, S. (2009)
      Human-centered and user-adaptive systems are at the heart of the Design for All and Ambient Intelligence concepts. Evidently, user models are necessary "ingredients" of such systems. We present a user model for navigation ...