Design and operation of a protection system for transformers with superconducting windings

Power transformers with superconducting windings need a protection system to prevent damage to the low-loss superconducting winding by an abnormally high current. The generally accepted protection technique which uses auxiliary coils has been analysed using a network representation. The current distribution between main and auxiliary coil is expressed in terms of geometrical parameters. Experimental data on current transfer and main coil recovery in a test transformer are presented and a method of obtaining a very low auxiliary coil current is suggested

The Perceived Motivational Impact of Voice-over-PowerPoint™ on Part-time Adult Learners in a Distance Learning Environment

The primary purpose of this study was to determine whether well-designed instructional material based on motivational theory and blended learning theory has the intended impact on the learning motivation of adult learners in a distance education environment. This study used Voice-over-PowerPoint™ technology as a medium to deliver subject specific instruction based on motivational theory as supplementary content to the course curriculum. This empirical study was conducted over a period of approximately two months on a sample of 57 adult learners who were enrolled for a distance education course for non-degree purposes at a tertiary education institution. Quantitative research methods were applied and data was collected using two motivation-measuring surveys: (1) The Course Interest Survey; and (2) The Instructional Materials Motivation Survey, which were both developed by Keller. Motivational strategies were designed for the chosen educational technology, Voice-over-PowerPoint™ (VoP) videos, using Keller’s Attention, Relevance, Confidence and Satisfaction (ARCS) model of motivation. These strategies were then delivered via the learner management system for learners to use at their convenience. This research suggests that overall, learner motivation can be affected by external conditions such as well-designed instructional material, and further supports the ARCS model. Furthermore, the use of VoP videos as a viable medium for delivering motivational strategies in a blended, distance learning environment was validated

Using market-based indicators to assess banking system resilience

This report reviews the use of quantitative tools to gauge market participants’ assessment of banking system resilience. These measures complement traditional balance-sheet metrics and suggest that markets consider large Canadian banks to be better placed to weather adverse shocks than banks in other advanced economies. Compared with regulatory capital ratios, however, the measures suggest less improvement in banking system resilience since the pre-crisis period

Speculative Ethnology

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Two teachers are better than one : collaborative teaching as an approach to promote whole brain learning

PURPOSE – This paper aims to focus on the thinking styles of a group of Accounting students, and to determine whether team teaching by two criteria-specific lecturers can be an effective collaborative teaching approach to accommodate students’ diverse learning preferences. Research on thinking and learning processes led to a four-quadrant whole-brain model of people’s thinking styles and associated learning preferences. The model can be used to identify and accommodate students’ diverse thinking styles and learning preferences. DESIGN/METHODOLOGY/APPROACH – A case study approach was followed, using multiple data collection methods. The thinking styles of 288 students and two lecturers were surveyed using a thinking style questionnaire and the Herrmann Brain Dominance Instrument. The results of the collaborative teaching approach were obtained by way of a survey questionnaire providing both quantitative and qualitative feedback, as well as a SWOT analysis completed by the involved lecturers. FINDINGS – The main results suggest that a collaborative teaching approach can address students’ diverse learning preferences, although some students may find constant switching between lecturers distracting. RESAERCH LIMITATIONS/IMPLICATIONS – The collaborative teaching approach in the teaching interaction cannot be isolated. Collaborative teaching was not repeated or extended due to resource constraints. ORIGINALITY/VALUE – Academics from all disciplines recognise a need for a teaching practice that addresses students’ diverse learning preferences. Hitherto, outside of special education, collaborative teaching has received little scholarly attention, especially as an approach to address tertiary students’ diverse learning preferences.http://www.emeraldinsight.com/loi/medarhb201

Wijzig het digitale-euro voorstel van een risico in een kans voor privacy

Eind juni diende de Europese Commissie een wetsvoorstel in voor de invoering van een digitale euro. Wat betekent dit digitale-eurovoorstel voor de betaalprivacy, en is dit wel wenselijk? (opiniebijdrage

Experimental investigation of the loss characteristics of superconductors for AC power applications

Recent studies confirm the economical feasibility of the application of superconductors in AC power apparatus. The low-loss conductor which has been proposed still only exists in theory. Simple calculations show that the economic criterion described by Ogasawara and Hlásnik is inaccurate because of an oversimplified hysteresis loss formula. A necessary modification shows that stricter demands will have to be made. As production of ultrafine filaments is a big technological problem, final diameter reduction by rolling instead of drawing is proposed. The expected better performance of a rolled composite has been verified experimentally in test coils as well as in transformer geometry. Experimental set-up and results are presented

A historical overview of the origins of anti-shark measures in Natal, 1940-1980.

Thesis (M.A.)-University of KwaZulu-Natal, 2006.This thesis studies the origins of anti-shark measures in Natal, highlighting the relationship between beach recreation, anti-shark measures and the important influence of human perceptions of sharks. It focuses on key events such as the "Black December" when seven shark attacks occurred off the South Coast of Natal between December 1957 and April 1958; the rise of beach recreation in Natal; the role of the press (and later the electronic media) in the dissemination of the 'man-eating' shark myth; and the deployment of anti-shark measures off the Natal coast. The increased popularity of the beach in Natal during the 1940s and 1950s meant that the beach was frequently being used for recreational activities. However, with this increase there was an increase in shark attacks off the Natal coast. The relationship between beach recreation and shark attacks is key to this study. The first nets were deployed off the Durban beachfront in 1952. The influence of the press, the increase of popular beach recreational activities in the 1950s and the unfortunate events of "Black December" led to the deployment of the nets off the South Coast in the 1960s, and these are currently still in use. Alongside the deployment of the nets was a rise in scientific research into shark biology and anti-shark measures in the 1960s. This thesis traces shifting trends in shark research from the 1960s to the 1970s. For instance, in the 1960s, shark research focused primarily on shark biology and the ways in which the study of the behaviour of sharks could prevent shark attacks. In. the 1970s, shark research shifted towards the study of anti-shark measures. Both beach recreation and shark research have influenced human perceptions of sharks. This thesis covers a period when the human perception of sharks was more hostile than it would become after the rise of marine conservation and the commercial regard for the preservation of sharks from the 1980s. It also analyses the human fear of sharks and how this fear has developed over time