Web-based eTutor for learning electrical circuit analysis

This paper discusses a web-based eTutor for learning electrical circuit analysis. The eTutor system components, mainly the user-interface and the assessment model, are described. The system architecture developed provides a framework to support interactive sessions between the human and the machine for the case when the human is a student and the machine a tutor and also for the case when the roles of the human and the machine are swapped. To motivate the usefulness of the data gathered, some examples of interactive sessions are given and models to capture both declarative and procedural knowledge during learning are discussed. A probabilistic assessment model is reviewed and future directions in the field of eTutors for electrical circuits are discussed.peer-reviewe

Modeling electromagnetic interference generated by a WLAN system onboard commercial aircraft

This work forms part of the project HIRF SE which is financially supported under the European Union 7th Framework Programme (FP7). The authors are solely responsible for the contents of the paper which does not represent the opinion of the European Commission.The growing demand for the utilization of personal electronic communication devices onboard commercial aircraft necessitates the assurance of safety by airline operators and regulators. This implies that the potential risks posed by the deployment of wireless communication systems on critical aircraft equipment must be carefully assessed and countermeasures taken when required. In this paper, a model based on a ray-tracing algorithm is developed to calculate the electromagnetic interference incident on the fuselage structure of a commercial airline. The source of interference is a 2.4 GHz data communications network. Two scenarios are considered; the first assumes a base station in the centre of the cabin while the second considers four base stations, transmitting at a lower power, distributed along the cabin. The model first determines the propagation map generated by the base stations. These results are used to establish the transmission power required by the personal mobile devices which is then employed to determine the propagation map of each device. The overall electromagnetic interference map incident on the fuselage resulting from the onboard wireless network is generated by vectorially combining the resulting propagation maps. Results for the two scenarios are presented.peer-reviewe

Three Women, Three Generations: An In-Depth Case Study of Language Retention and Shift in One Family from the Maltese Australian Community in Melbourne

This paper analysis one family pertaining to the Maltese Australian community in Melbourne and investigates the retention of the Maltese language The Maltese Australian community is a small community that is getting smaller since migration from Malta to Australia has largely stopped Thus the Maltese language is spoken mostly by the first generation of immigrants who left the island after the Second World War seeking a better future The second generation born in Australia usually understands the language but lacks the opportunity or the will to speak the language except with members of the family The third generation raised in a multicultural country normally has very little fluency in the Maltese language The investigation is grounded in interview data gathered among a family of three generations of Maltese origin in Melbourne The findings of this research show that the aging population of the Maltese community and the dominance of the English language do not favour the retention of the Maltese language in the future With the end of the first generation of post-World War Two migrants and the emergence of the fourth and fifth generations probably there will be an absolute shift to English the de-facto national language of Australi

Simulating electromagnetic field inside small aircraft from wireless camera equipment

This work forms part of the project HIRF SE which is financially supported under the European Union 7th Framework Programme (FP7). The authors are solely responsible for the contents of the paper which does not represent the opinion of the European Commission.The proliferation of wireless systems has urged the aviation industry to consider the exploitation of such a technology to introduce new services and to curtail its cabling weight requirements. Nevertheless, prior to implementing such communication systems, manufactures must ensure that the paramount criterion of aircraft safety is unaffected and thus the potential electromagnetic (EM) field posed on aircraft equipment must be carefully assessed and respective countermeasures taken. To this end, this paper adopts a frequency-domain based three-dimensional ray tracing algorithm, based on geometrical optics to compute the EM field generated from the use of wireless camera equipment transmitting at 2.4 GHz inside the cabin of a typical business jet. The model comprehensively considers the various propagation methodologies utilized by multipath signals to provide a holistic understanding of the resultant average field strength incident at each location inside the fuselage.peer-reviewe

Objective video quality metrics for HDTV services : a survey

The exponential growth of video traffic is expected to reach 62% of the global Internet traffic by the end of 2015. This presents as a significant challenge for the television service providers who need to employ networking technologies to monitor specific Quality of Service (QoS) parameters such as packet loss rate, jitter and delay, to ensure an acceptable level of quality. However, recent research has demonstrated that the quality experienced by the end-user does not correlate to the QoS parameters employed by most service providers. This paper investigates the correlation between the QoS parameters and the quality perceived by the end. user. These results indicate that although the QoS parameters may sometimes achieve high correlation with respect to the quality perceived by the viewer, they still have large variances. This suggests that the QoS parameters are not enough to quantify the subjective quality with a high level of confidence. This work further compares a number of existing objective video quality metrics. The results presented in this paper show that the Full-Reference Motion based Video Integrity Evaluation (MOVIE) metric and the Spatio-Temporal Reduced Reference Entropic Differences (STRRED) metric achieve excellent correlation with the subjective scores. This research also demonstrates that the STRRED metric and its derivatives have several advantages over the MOVIE metric since less information needs to be transmitted and it is less computationally intensive.peer-reviewe

Small aircraft cockpit electromagnetic interference due to UMTS signal propagation

This paper implemented a ray-tracing based algorithm to calculate the EMI generated inside an aircraft cabin with particular emphasis on flight critical equipment such as the cockpit avionics panel. The interference level caused by the deployment of a UMTS Node B antenna for the provision of passenger communication was computed. The model was employed to study the effects of the multipath electromagnetic propagation attained from positioning a Node B antenna in different locations inside a relatively small tunnel shaped fuselage with dense furnishings. The proposed framework is also able to provide an all-encompassing understanding of the generated EMI, whilst offering support for the development of conscientious network design in aircraft.peer-reviewe