University of Piraeus

About: University of Piraeus is a education organization based out in Piraeus, Attiki, Greece. It is known for research contribution in the topics: Context (language use) & Computer science. The organization has 1731 authors who have published 6209 publications receiving 106699 citations.

Collaboration and fuzzy-modeled personalization for mobile game-based learning in higher education

Abstract: Mobile game-based learning constitutes a hot issue in the related scientific literature since it promotes learning through an entertaining way and fosters student motivation to increase engagement in the educational process. As such, it can enhance the learning process and improve student participation. Towards this direction, this paper investigates how mobile learning and game-based learning can be utilized in higher education settings and analyzes the pedagogical affordance of their adoption. As a testbed for our research, we designed and implemented Quiz Time! which is an intelligent mobile game-based learning application for assessing and advancing learners' knowledge in the programming language C#. Quiz Time! employs an assessing knowledge module for testing the knowledge of learners, a vectorial-based recommendation module for proposing personalized collaboration in group playing, a dynamic fuzzy logic-based advice generator for tailored assistance to learners' profile and misconceptions, and a cognitive learner modeler supporting the aforementioned modules. Quiz Time! was used in a higher education institution for an academic semester and was evaluated by students and computer science experts using an established framework and the statistical hypothesis test. Regarding the evaluation results, the computer science experts validated the pedagogical adequacy of the application and the students highlighted its positive impact on learning and its usefulness. A major conclusion is that incorporating personalization and collaboration in mobile game-based learning can further assist students in higher education towards advancing their knowledge level.

Dual-Hop Communication Over a Satellite Relay and Shadowed Rician Channels

Abstract: A dual-hop amplify-and-forward (AF) relaying scheme over shadowed Rician fading channels is investigated. Specifically, the source and destination nodes are equipped with $N$ and $M$ antennas, respectively, whereas the relay is equipped with a single antenna. Communication via satellite relaying represents a direct application of the considered infrastructure. To this end, we study the scenario when the source and the destination are terrestrial nodes, whereas the end-to-end communication is established through an intermediate AF relay node, which is a satellite. To fully exploit the spatial diversity provided by multiple antennas, maximum ratio transmission and maximum ratio combining are implemented at the source and the destination, respectively. First, a new closed-form expression for the probability density function (pdf) of the sum of independent and identically distributed (i.i.d.) squared shadowed Rician random variables is derived by assuming integer distribution parameters. Capitalizing on the latter pdf, new closed-form results for the cumulative distribution function (cdf) and the moment function of the end-to-end signal-to-noise ratio (SNR) are obtained. Particularly, the proposed unified analysis includes the channel-state-information (CSI)-assisted and the fixed-gain AF relaying protocols. New expressions for important performance measures, namely, the outage probability, the average symbol error probability (ASEP), and the ergodic capacity of the end-to-end SNR, are presented for both AF schemes. Moreover, some useful engineering insights are manifested, such as simplified asymptotic outage performance results, the diversity order, and the impact on the number of antennas at the source and the destination.