Τμήμα Μηχανικών Η/Υ και Πληροφορικής (Δημοσ. Π.Π. σε περιοδικά)

Permanent URI for this collection

Browse

Recent Submissions

Now showing 1 - 5 of 5
  • Thumbnail Image
    Item
    Open Access
    E-learning through Virtual Reality Applications: The Case of Career Counseling
    (Common Ground Research Networks, ) Kostopoulos, Konstantinos Panagiotis; Giannopoulos, Konstantinos; Mystakidis, Stylianos; Chronopoulou, Kiriaki; Μυστακίδης, Στυλιανός
    VR can be defined as a three-dimensional space that provides a strong degree of interaction with the user, including real-time simulation and interactions through multiple channelssenses. It is not just a reproduction of conventional reality, but creates synthetic realities without precedent. It has been used in various fields, e.g. education, medicine, architecture, assistance to persons with disabilities, etc. VR leads to the development of new forms of counseling, e.g. via asynchronous learning platform, videoconferencing, social networking, etc. By using the three-dimensional virtual immersive learning environments of “Open Workshop on Information Literacy” of Patras’ University Library, we organized and conducted three educational workshops about career consulting with 50 participants. The Open Workshop is an open and free blended learning initiative for providing flexible training services on academic & professional development to the university’s academic community and beyond. In this paper, the results through practice of such an initiative are described, i.e. the prerequisites for its success, its capabilities/restrictions, the participants (and potential) and the way they participated, users’ feedback (evaluation and outcomes) and the possibilities/limitations of Virtual Reality (VR) applications in Career Counseling and especially in providing educational and vocational information through already implemented actions.
  • Thumbnail Image
    Item
    Open Access
    Classical impurities associated to high rank algebras
    Δόικου, Αναστασία; Doikou, Anastasia
    Classical integrable impurities associated with high rank () algebras are investigated. A particular prototype, i.e. the vector non-linear Schrödinger (NLS) model, is chosen as an example. A systematic construction of local integrals of motion as well as the time components of the corresponding Lax pairs is presented based on the underlying classical algebra. Suitable gluing conditions compatible with integrability are also extracted. The defect contribution is also examined in the case where non-trivial integrable conditions are implemented. It turns out that the integrable boundaries may drastically alter the bulk behavior, and in particular the defect contribution.
  • Thumbnail Image
    Item
    Open Access
    Jumps and twists in affine Toda field theories
    Δόικου, Αναστασία; Doikou, Anastasia
    The concept of point-like “jump” defects is investigated in the context of affine Toda field theories. The Hamiltonian formulation is employed for the analysis of the problem. The issue is also addressed when integrable boundary conditions ruled by the classical twisted Yangian are present. In both periodic and boundary cases explicit expressions of conserved quantities as well as the relevant Lax pairs and sewing conditions are extracted. It is also observed that in the case of the twisted Yangian the bulk behavior is not affected by the presence of the boundaries.
  • Thumbnail Image
    Item
    Open Access
    Gathering and processing energy consumption data from public educational buildings over IPv6
    Koumoutsos, Konstantinos; Kretsis, Aristotelis; Kokkinos, Panagiotis; Varvarigos, Emmanouel; Nikolopoulos, Vassilis; Gkioxi, Eirini; Zafeiropoulos, Anastatios; Κουμούτσος, Κωνσταντίνος; Κρέτσης, Αριστοτέλης; Κόκκινος, Παναγιώτης; Βαρβαρίγος, Εμμανουήλ; Νικολόπουλος, Βασίλης; Γκιόξη, Ειρήνη; Ζαφειρόπουλος, Αναστάσιος
    Background: Reducing energy consumption and CO2 emissions in order to address climate change requires behavioral changes by the citizens, who will have to adopt more environmentally friendly and energy-saving practices. Methods: We present a system and corresponding practices for gathering energy consumption data from public school buildings over the Internet, processing them to identify hidden correlations and produce actionable advice and presenting the results in real-time to its occupants over the Web. We describe the metering infrastructure installed at schools for energy consumption monitoring and the related actions carried out in order to motivate local school communities towards an environmentally friendly behavior. The introduction of IPv6 was found to be a key enabling technology for setting up such a system in a simple, secure, and efficient way. Results: The proposed system and processes are put under test in a pilot installation composed of about 50 IPv6-enabled schools of the Greek School Network (GSN). These are also combined with appropriate educational and social engagement tools. In this way, energy consumption, operating costs, and greenhouse effects can be reduced in the area of educational and public administration buildings in general. Thus, people become almost instantly aware of the energy and environmental implications of their actions, which motivates them towards behavioral changes and the adoption of environmentally friendly practices. Conclusions: The pilot provides a good example of collaboration between the ICT sector, the smart building and automation vendors, and the public authorities.
  • Thumbnail Image
    Item
    Open Access
    Cross-tier interference management schemes in cognitive heterogeneous networks
    Tzelatis, Ioannis; Berberidis, Kostas; Τζελάτης, Ιωάννης; Μπερμπερίδης, Κώστας
    To satisfy the ever-increasing data rate and service coverage demands, wireless communication networks evolve into heterogeneous networks (HetNets), where low-cost small base stations are embedded in conventional macrocells. Intercell interference emerges as the key capacity-limiting factor in such dense networks, restricting the reusability of spectral resources. Therefore, advanced interference mitigation techniques relying on multi-cell cooperation have attracted significant attention from the wireless industry and academia. This paper discusses interference management schemes for multi-tiered spectrum access in next-generation HetNets. A novel scheme based on full system cognition and base station cooperation is proposed as an enabler for high-capacity HetNets. In addition, practical implementation and operational challenges are investigated.