Theory and performance of auxiliary discharge thermionic energy converters

Auxiliary discharge thermionic energy converter - gas discharge processes, and plasma parameter

Some factors influencing radiation of sound from flow interaction with edges of finite surfaces

Edges of surfaces which are exposed to unsteady flow cause both strictly acoustic effects and hydrodynamic effects, in the form of generation of new hydrodynamic sources in the immediate vicinity of the edge. An analytical model is presented which develops the explicit sound-generation role of the velocity and Mach number of the eddy convection past the edge, and the importance of relative scale lengths of the turbulence, as well as the relative intensity of pressure fluctuations. The Mach number (velocity) effects show that the important paramater is the convection Mach number of the eddies. The effects of turbulence scale lengths, isotropy, and spatial density (separation) are shown to be important in determining the level and spectrum of edge sound radiated for the edge dipole mechanism. Experimental data is presented which provides support for the dipole edge noise model in terms of Mach number (velocity) scaling, parametric dependence on flow field parameter, directivity, and edge diffraction effects

Gowin's Knowledge Vee and the integration of philosophy and methodology : a case study

Universities with a strong research tradition commonly have courses or modules examining the tradition’s philosophies and methodologies to prepare their students to undertake research programmes. Recently, however, authors have called for wider debate concerning how we teach these courses and this paper is intended, in part, to make a contribution to this debate. The Research Philosophy and Methodology module examined here makes an intriguing case study because of a number of distinctive characteristics. The teaching philosophy of the module is social constructivist and it uses Gowin’s Knowledge Vee as its main heuristic device. This facilitates the construction of knowledge about philosophy and methodology in an integrated manner. The module has also been designed for both physical and human geography students at the introductory post-graduate level. There is, therefore, a second element of integration in the curriculum. Lastly, the module is predominantly web-based, being taken by distance students through the exchange agreement between Rhodes University, South Africa, and the University of Trollhättan-Uddevalla, Sweden. Evidence from reflective exercises shows that the learners’ understanding of research and the research process has deepened considerably through using Gowin’s Vee. Furthermore, using the Knowledge Vee in the web-based context has facilitated the integrative aspects of the module

Between the Reds and the Greens: a geographical interpretation of the land question in South Africa

This inaugural lecture is in two parts: each related to a different nexus of the four types of scholarly activity. The first reflects on my career and is an examination of how I have developed as a teacher and learner. The key scholarly activities being discovery, integration and teaching. The second part reflects on the evolution of my research interests and leads up to an examination of the land question in South Africa. The scholarly activities in this part of the lecture are discovery, integration and application

Bleak future for multi-party elections in Kenya

With attention turning towards Kenya's second multi-party elections, due to be held before the end of 1997, it is imperative to look back to the flaws in the system which helped deliver President Daniel arap Moi and the Kenya African National Union (KANU) their victories in 1992. At present there is no sign of these defects being eradicated and the creation of new districts since then has demonstrated the Government's intention of enhancing an already biased structure. The underlying distribution of tribes and ethnic groups has had a fundamental impact on the electoral geography of Kenya, since they have controlled the delimitation of both the parliamentary constituencies and the administrative machinery of the whole country

Geography of African development : an alternative curriculum

The Geography of African Development module is part of a year-long Third Year level geography course on Africa that has been offered at Rhodes University since 2002. The course is an exception to the dominant trend, both locally and internationally, which has witnessed a major decline in the teaching of regional geography and area studies. This paper examines how adopting a constructivist approach to the module's curriculum enabled learners to develop geographical skills at the same time as Africanising the curriculum